Cannabis Grow

Through local examples, garden activities and guest speakers, the curriculum connects students to other change makers and empowers them with agency to help build a more sustainable food system in their community. Students learn to think of climate change as more than “just” a science problem: it is a social problem requiring action and responsibility from all levels of society—individual to international. Each of the six lessons involves students in activities that translate regenerative agriculture theory into practice . The curriculum provides opportunities for students to learn scientific facts , share personal narratives , and enact hands-on solutions to climate change via school gardens . Students learn about the carbon cycle and soil carbon sequestration while building compost piles. They learn about the negative effects of elevated CO2 in the atmosphere globally and then help lower CO2 locally through increasing plant photosynthetic activity. The pedagogical framework for the curriculum is inspired by Paolo Freire’s critical pedagogy and other more current framings of a signature pedagogy for sustainable food systems education . Educators facilitate collective learning experiences that are often subversive in nature and seek to disrupt inequitable outcomes, both environmental and social. Curriculum implementation followed a co-teaching model. The researcher-teacher partnership draws on complementary domains of expertise: content expertise from the researcher, and classroom management/student dynamic expertise from the teacher. Two symbiotic goals are addressed using co-teaching as an implementation method: 1) students learn climate change from a content expert, and 2) teachers increase knowledge and competence in climate change instruction, vertical grow room design allowing future students to benefit from a better-trained instructor and serving as a form of professional development.

Studies have shown repeatedly that the best way to improve student performance across a range of subjects is to boost teacher knowledge and competency . This type of participatory, co-teaching implementation inherently limits ability to statistically analyze a large, representative, or randomly generated dataset of students. It is grounded in social science theory of the qualitative, in-depth case study. Each school required slightly different implementation of the curriculum. In one case snow days canceled several coteaching sessions, which then had to take place via Skype. Taken as a whole, these four cases shed light on important adjustments that can be made to tailor climate change education interventions to site-specific school needs. Pragmatically, meeting unique school needs is a prerequisite for implementing any non-mandatory education intervention in partnership with schools. The study simultaneously investigates student responses to an experiential climate curriculum, and teacher responses to co-teaching as a form of professional development. The methods used for evaluating curriculum efficacy include 1) semi-structured teacher interviews, 2) student surveys , and 3) participant-site observation. Triangulation of these methods improves the validation of results. Deeper understanding can be gained from a small set of cases on CCE, and best practices can then be applied to a larger universe of schools. More specific to each method, teacher interviews followed a six-question interview guide and were semi-structured in nature. Preliminary student surveys provide a baseline for student knowledge and engagement. Compared with post-intervention surveys, this allows basic statistical analysis to define the effect size in the sample population and whether it is significant.

The survey assessment includes 10 knowledge-based questions on climate science and food systems applications, as well as 19 engagement questions asking opinion statements measured on Likert-type scales. This multi-faceted assessment of climate literacy recognizes that “knowledge about climate change can be divided into several general and overlapping categories: knowledge about how the climate system works; specific knowledge about the causes, consequences, and potential solutions to global warming; contextual knowledge placing human-caused global warming in historical and geographic perspective; and practical knowledge that enables individual and collective action” . The engagement questions adapt the Six Americas survey questions to capture students’ change in engagement towards climate change following the curriculum intervention. Participant and site observation over a six week period captures important features of the school climate, both environmental and social, that help contextualize interpretation of results. The quality of the school garden, behavioral norms, and student informal interactions are all variables of interest for understanding other forms of data collection. In climate literacy evaluations, it is important to understand student intention to take action and follow up to document concrete examples of students taking action, which goes beyond simple survey and interview protocols.

Certainly, questions can be posed to students asking whether they feel more empowered to seek out their own additional knowledge and participate in climate actions, but ideally these questions can be followed up with evaluation tools documenting actual action outcomes. This was not possible in the contexts of study reported on below but should be a focus for future student climate literacy evaluations. Results presented and discussed below are broadly relevant to climate change education interventions, with some insights as well into the value of food as an engaging entry point or frame for the climate education conversation.Attitude and engagement questions revealed higher levels of concern along the Six Americas spectrum than the national average. The first 10 questions were adapted almost directly from the Six Americas survey, with some modifications for student-friendly language. An additional nine questions were added dealing specifically with food systems, behavior and climate change. Based on the first 10 questions, students were categorized into the six segments from alarmed to dismissive, with almost all students falling in the top three categories . Students demonstrated an overall increase in engagement although this was difficult to measure with precision due to inconsistencies within individual student response patterns. A preliminary analysis is valid for determining directional effect arrows and assessing whether pilot programs show promise, and thus were adequate for this evaluation. Precision could be added in future iterations by simplifying answer scales so they are consistent, and then quantifying student attitudes on a numerical basis. The survey was a bit long to hold student attention, and survey fatigue was a confounding variable in some cases. Work is underway by the Yale Project on Climate Change Communications to create a four-question survey version for teens , which will be a valuable improvement for future studies. Informal observations and conversations reveal a notable curiosity and interest among youth in learning more about climate change. A commonly expressed sentiment, especially at the outset of the curriculum intervention, is that climate change is an important issue that students feel they should know more about. This is mirrored in national statistics reporting that American teens recognize their limited understanding of climate change, and 70% say they would like to know more about the subject .Post-intervention teacher interview themes revealed a widespread appreciation of coteaching as a mechanism for delivering climate change instruction. All teachers interviewed expressed enthusiasm for having a content expert present to deliver instruction on climate, complementing the garden teachers’ expertise in food-related topics, classroom management and student behavior. The positive response from teachers is important to contextualizing student results, as the more enthusiastic and knowledgeable teachers became about climate change connections in the school garden, grow vertical the more engaging lessons became for students.Teachers were able to learn from the experience and expressed desire to replicate elements of the curriculum on their own in the future, thus meeting one of the process-specific goals of the research. Interviewees also revealed a common theme of searching for hope and action amidst the daunting reality of climate change; the garden and classroom were often identified as key arenas where hope and solution steps exist. Key quotes from interviews are highlighted in Table 15 below.These results, in particular the challenges highlighted by teachers, closely match national findings on climate change education. In a recent national review of science teachers, the first nationally representative study of science educators to focus on climate change, fewer than half of all teachers reported any formal coursework on climate change, yet over two thirds would like targeted professional development opportunities to allow them to dive in deeper to this complex and emotionally sensitive topic .

It is well established that teachers are in need of professional development in order to teach an unfamiliar subject with confidence and competence, and several national leaders in climate education are addressing this . Having a climate science “expert” in the classroom to co-teach a climate change curriculum for the first time is another promising form of PD explored here. Partnerships emerged as a key feature enabling success of food and climate education in schools, mirroring the findings in example 1 above. Partner organizations and individuals are able to provide infrastructure support, outdoor learning environments, guest speakers to reinforce climate education units, and program evaluation assistance. Questions of how to scale impact via partnerships at the district or state level and education policy implications are discussed below. Examining results by school context offers strategies for scaling this type of intervention in rural vs. urban school districts. Students at the Lopez school, with abundant local farm and forest resources to devote to furthering climate curricula endeavors, selected a biochar experiment as a class climate action project, and will be applying locally produced biochar to test plots in the school garden to compare with non-treated plots , in partnership with the community. This community-school partnership adds to the body of successful climate change engagement strategies meriting replication, particularly other rural communities where local farmers might be interested in participating in farm to school programming at the school or district level.Students in Oakland had more immediate food-security and job-related concerns that focused their attention on school gardening as a vehicle for meeting short-term goals rather than long-term goals . Food insecurity is a widespread problem coexisting with food sovereignty and community divestment issues . Linking climate change with green career pathways in food and agriculture was a more effective educational strategy in Oakland classrooms to capture student interest.Experiential food and climate change education is an emerging branch of CCE with great potential, where the school garden provides one context for experiential climate learning while many others are possible . By emphasizing and teaching local forms of food production and consumption, this CCE example seeks to localize climate stewardship and in doing so reduce the carbon footprint of food system products and processes. The food-climate nexus diagram presented in Chapter 1 offers both an impetus for scaling this form of integrated food-climate education, and an example of how to do so while visualizing food-climate interactions. This chapter reports on initial positive results from integrating CCE into both the humanities and school garden classrooms. In the case of humanities-focused CCE, students not only demonstrated gains in climate literacy, but also improved their reading comprehension. Sixth grade students performed at a level equivalent to their eighth-grade peers in terms of listing numerous climate mitigation strategies, and reported both looking up new information and speaking with friends/family about climate change more frequently than all other middle school grades. The examples from school garden classrooms more explicitly adopt and test the hypothesis that experiential CCE is more effective than didactic or lecture-based climate instruction. Results show improvements in student learning and strong student interest in the topic. However, further evaluation methodology development is needed to best capture the impacts on student action and behavior. In order to understand the efficacy of experiential CCE relative to CCE that is not experiential, a controlled experiment would be required that uses the same evaluation methodology for students with and without experiential CCE. This methodology would ideally comprise and observational element where teachers report on student “climate actions” over the course of a defined time period. In future studies, a list of core “climate actions” could be developed as a baseline for evaluators to assess whether students are carrying out these activities . Rather than being treated as its own subject, or topic to be covered in science classrooms, climate change is an overarching frame that infuses all sorts of school activities, processes, and classrooms, from the transportation that bring students to school, to the food that is served in the cafeteria, to the content students are covering with their mathematics, physics, government, or garden teachers. The sooner schools, farms, gardens, and other centers for education embrace climate change as a unifying theme cutting across and informing their operations, the easier CCE will be to implement and scale. Schools and youth represent an underutilized resource in the climate and food behavior change initiative.

We discuss the results, showing how an agroecological method of inquiry amplifies important aspects of urban food production spaces and identifies gaps in national urban agriculture policy circles. We conclude by positing unique characteristics of urban agroecology in need of further studies and action to create equitable, resilient and protected urban food systems.Agricultural policy in the United States is primarily concerned with yield, markets, monetary exchange, and rural development. Farms are defined as “any place from which $1,000 or more of agricultural products were produced and sold, or normally would have been sold, during the year” . Urban agriculture has been proliferating across the country in the last decade on both public and private lands, as both for-profit and nonprofit entities, with diverse goals, missions and practices largely centered on food justice priorities and re-localizing the food system. Yet U.S. agriculture policy has been struggling to keep up. In 2016, the USDA published an Urban Agriculture Toolkit, which aims to provide aspiring farmers with the resources to start an urban farm including an overview of the startup costs, plant drying rack strategies for accessing land and capital, assessing soil quality and water availability, production and marketing, and safety and security .

The 2018 U.S. Farm Bill provides a definition of urban agriculture to include the practices of aquaponics, hydroponics, vertical farming, and other indoor or controlled environment agriculture systems primarily geared towards commercial sales. In both the Toolkit and Farm Bill, non-profit, subsistence, and educational urban farming enterprises are not well integrated or included in the conceptualization of UA. While there are many definitions of urban agriculture in the literature from the simplest definition of “producing food in cities” to longer descriptions of UA such as that of the American Planning Association that incorporate school, rooftop and community gardens “with a purpose extending beyond home consumption and education,” the focus of many UA definitions used in policy arenas continues to center around the production and sale of urban produced foods. Accordingly, food systems scholars have recognized that “Urban agriculture, [as defined], is like agriculture in general”, devoid of the many political, educational, and food justice dimensions that are prioritized by many U.S. urban farming efforts. Thus the social-political nature of farming, food production, and food sovereignty are not invoked by formal UA policy in the U.S. Many goals and activities common in urban food production, including education, nonmonetary forms of exchange, and gardening for subsistence are obscured by the productivist definitions and can be thus neglected in policy discussions. Furthermore, UA policy in the U.S. remains largely agnostic about the sustainability of production practices and their impact on the environment. While U.S. agriculture policy narrowly focuses on the production, distribution and marketing potential of UA, broader discussion of its activities and goals proliferate among food systems scholars from a range of fields including geography, urban planning, sociology, nutrition, and environmental studies.

These scholars are quick to point out that UA is much more than production and marketing of food in the city and includes important justice elements . In the Bay Area context, we continue to see the result of this dichotomy: thriving urban farms lose their leases , struggle to maintain profitability or even viability and encounter difficulties creating monetary value out of their social enterprises. In light of the ongoing challenge to secure longevity of UA in the United States, there is a need for an alternative framework through which food and farming justice advocates can better understand and articulate what UA is, and why it matters in cities.Agroecology is defined as “the application of ecological principles to the study, design and management of agroecosystems that are both productive and natural resource conserving, culturally sensitive, socially just and economically viable” , and presents itself as a viable alternative to productivist forms of agriculture. Agroecology in its most expansive form coalesces the social, ecological, and political elements of growing food in a manner that directly confronts the dominant industrial food system paradigm, and explicitly seeks to “transform food and agriculture systems, addressing the root causes of problems in an integrated way and providing holistic and long-term solutions” . It is simultaneously a set of ecological farming practices and a method of inquiry, and, recently, a framework for urban policy making ; “a practice, a science and a social movement” . Agroecology has strong historical ties to the international peasant rights movement La Via Campesina’s food sovereignty concept, and a rural livelihoods approach to agriculture where knowledge is created through non-hegemonic forms of information exchange, i.e. farmer-to farmer networks . Mendez et al. describe the vast diversity of agroecological perspectives in the literature as “agroecologies” and encourage future work that is characterized by a transdisciplinary, participatory and action-oriented approach. In 2015, a global gathering of social movements convened at the International Forum of Agroecology in Selengue, Mali to define a common, grassroots vision for the concept, building on earlier gatherings in 2006 and 2007 to define food sovereignty and agrarian reform.

The declaration represents the views of small scale food producers, landless rural workers, indigenous peoples and urban communities alike, affirming that “Agroecology is not a mere set of technologies or production practices” and that “Agroecology is political; it requires us to challenge and transform structures of power in society” . The declaration goes on to outline the bottom-up strategies being employed to build, defend and strengthen agroecology, including policies such as democratized planning processes, knowledge sharing, recognizing the central role of women, building local economies and alliances, protecting biodiversity and genetic resources, tackling and adapting to climate change, and fighting corporate cooptation of agroecology. Recently, scholars have begun exploring agroecology in the urban context. In 2017, scholars from around the world collaborated on an issue of the Urban Agriculture magazine titled “Urban Agroecology,” conceptualizing the field both in theory and through practical examples of city initiatives, urban policies, citizen activism, and social movements. In this compendium, Van Dyck et al. describe urban agroecology as “a stepping stone to collectively think and act upon food system knowledge production, access to healthy and culturally appropriate food, decent living conditions for food producers and the cultivation of living soils and biodiversity, all at once.” Drawing from examples across Europe, Africa, Latin America and Asia and the United States, the editors observe that urban agroecology “is a practice which – while it could be similar to many ‘urban agricultural’ initiatives born out of the desire to re-build community ties and sustainable food systems, has gone a step further: it has clearly positioned itself in ecological, social and political terms” . Urban agroecology takes into account urban governance as a transformative process and follows from the re-emergence of food on the urban policy agenda in the past 5-10 years. However, it requires further conceptual development. Some common approaches in rural agroecology do not necessarily align with urban settings, hydroponic rack where regenerative soil processes may require attention to industrial contamination. In other cases, the urban context provides “specific knowledge, resources and capacities which may be lacking in rural settings such as shorter direct marketing channels, greater possibility for producer-consumer relations, participatory approaches in labour mobilisation and certification, and initiatives in the area of solidarity economy” . Focusing on the social and political dimensions of agroecology, Altieri and others have explicitly applied the term “agroecology” to the urban context, calling for the union of urban and rural agrarian food justice and sovereignty struggles . Dehaene et al. speak directly to the revolutionary potential of an agroecological urban food system, building towards an “emancipatory society” with strong community health and justice outcomes.As noted, there are many dimensions of agroecology and ways in which it is conceptualized and applied. We employ the 10 elements of agroecology recently developed by the UN FAO in our discussion of urban agroecology. These 10 elements characterize the key constituents of agroecology including the social, ecological, cultural, and political elements. Despite the emancipatory goals of agroecology, a recent review of the literature by Palomo-Campesino et al. found that few papers mention the non-ecological elements of agroecology and fewer than 1/3 of the papers directly considered more than 3 of the 10 FAO-defined elements. In an effort to help guide the transition to more just and sustainable food and agricultural systems in cities across the U.S., we propose that food system scholars and activists consider using the 10 elements as an analytical tool to both operationalize agroecology, and to systematically assess and communicate not only the ecological, but also the social, cultural and political values of urban agroecology.

“By identifying important properties of agroecological systems and approaches, as well as key considerations in developing an enabling environment for agroecology, the 10 Elements [can be] a guide for policymakers, practitioners and stakeholders in planning, managing and evaluating agroecological transitions.In San Francisco’s East Bay region, urban food production proliferates in schoolyards, in half-acre lots converted to urban farms, on rooftops, and in backyards reflecting a diversity of participants, goals, impacts and challenges . The San Francisco East Bay region is also experiencing rapid gentrification and a worsening affordable housing crisis coupled with high rates of income inequality and food insecurity. The challenge of urban soil contamination creates tradeoffs for aspiring growers between vacant lot availability and siting on the most heavily polluted plots . Specific city policies vary in the degree to which they support or discourage urban agricultural activities, and availability of arable land across the East Bay is uneven. Our case study focuses on urban farmers in the East Bay spanning over 28 miles from El Sobrante in the northeastern edge of the bay, to Hayward in the southern East Bay as shown in Figure 13. We include both for-profit and non-profit farms ranging from educational school gardens to roof-top farms marketing microgreens.We employed a participatory and collaborative mixed methods approach, involving diverse stakeholders from the East Bay Agroecosystem. We held two stakeholder input sessions involving over 40 urban farmers and food advocates to co-create the research questions, advise on the data collection process, interpret the results, and prioritize workshop topics for the community. We administered an online Qualtrics survey to 120 urban farms in the East Bay that had been previously identified by the University of California Cooperative Extension Urban Agriculture working group and additional outreach. The survey launched in Summer 2018, which is a particularly busy time for farmers, and in response to farmer feedback was kept open until November 2018. 35 farmers responded in total, representing a 30% response rate. While there are limitations in our ability to generalize findings to the East Bay urban farming landscape as a whole due to the relatively small sample size, we obtained a fairly representative sample of the diversity of farm types in the East Bay based on our typology of the original 120 farm types . Survey questions fell into nine categories: 1) Background Info, 2) Farm Description, 3) Operating Expenses and Revenues, 4) Land Access and Tenure, 5) Production and Soil Health, 6) Distribution, 7) “Waste” and Compost, 8) Food Access, and 9) Training, Communications, and Follow Up. There were a few open-ended questions allowing farmers to express what they saw as the three largest challenges facing urban agriculture operations in the area, and policy-relevant suggestions for securing spaces for urban farms and increasing community food security. In addition, we interviewed five urban farmers to deepen our understanding of the social, political, economic, and ecological constraints under which their farms operate. These farmers are particularly involved in networking efforts to strengthen urban farm viability in the East Bay. Four out of five represent locally prominent non-profit farms and one subject represents an alternative cooperatively-run urban farm; three interview subjects are women and two are men. Our study complied with UC Berkeley’s Institutional Review Board protocol for the protection of human subjects and all participants gave consent for participation.Most farms including the UC Oxford Tract and Gill Tract Farms, distribute food to a diverse array of community organizations. The two aforementioned farms together distribute food to over 50 community organizations, ranging from food pantries to community health groups to native land trusts seeking to feed and reclaim land for those of indigenous heritage. 52% of respondents distribute all food within 5 miles of their farm, while 70% distribute within 10 miles.

Much of the literature is theoretical, focused on the production potential of urban agriculture, while more work is needed to understand and overcome barriers to access and distribution among communities in need. Without understanding the actual links between UA and food security or which specific characteristics, models or approaches reduce insecurity, urban policymakers and advocates risk backing policies that could have unintended consequences or negative impacts on vulnerable individuals and communities. This literature review explores the intersection between UA and food security to better understand how and to what extent UA addresses food access challenges facing low-income communities in urban areas, and the conditions that either enable or inhibit UA initiatives. The landscape of what constitutes “urban agriculture” is extremely heterogeneous: UA encompasses vertical and rooftop farming, urban foraging, community and residential gardens, and commercial urban farms. Some urban farms operate as for-profit businesses, whereas others operate as nonprofits reliant on grants, subsidies and donations to sustain their operations. For the purposes of city planning, the American Planning Association defines UA as the “production,marketing, and distribution of food and other products in metropolitan areas and at their edges, flood tables for greenhouse beyond what is strictly for home consumption or educational purposes” . In its simplest form, UA is “growing food in cities” . We define UA broadly to encompass the full range of activities involved in urban food production including self-production and subsistence agriculture.

In doing so, we follow scholars who have sought to measure the contributions of a wide range of UA activities . We see three trends in current scholarship on UA in relation to community food security: a focus on the production potential of urban lands, case studies highlighting various nutritional, health, and other community benefits or outcomes from urban gardening initiatives, and more critical analyses of UA through food justice and equity lenses. Some scholars, for example, have mapped vacant lots in Oakland and backyard gardens in Chicago , predicting yield, to illustrate the production potential of UA. Others demonstrate, through case studies, the productivity of urban gardens and the value of the food they produce in meeting nutritional needs of low-income communities, particularly households involved in gardening directly . Robust theoretical analyses have emerged critiquing the risks of UA when approached without an equity lens, potentially reinforcing structural injustices and racism and negatively impacting the communities they purportedly serve . Deeper historical and structural challenges including poverty, racism, and divestment in specific communities and neighborhoods are increasingly being recognized as the root causes of the current problem of unequal access to sufficient supplies of safe, nutritious, affordable, and culturally acceptable food facing cities . Designating land for agricultural use in urban areas may conflict with other city planning priorities around affordable housing, gentrification, and living. Because of the persistent legacy of systemic discrimination, it is neither inevitable nor guaranteed that urban agriculture will redress food system inequities; in fact, urban farms can sometimes lead to displacement through eco-gentrification . This is a particularly acute concern in areas experiencing housing pressures and population growth, such as the San Francisco Bay area and New York City. UA can also perpetuate positions of privilege within the food system by benefiting those who already hold power .

Critical food systems scholars question, “who really benefits, and who loses in specific efforts to promote urban farms in the ‘sustainable city’ landscape?” and, “how can white food activists reframe their work so as not to fuel displacement of residents of color?” . We examine the role of urban agriculture in addressing food insecurity from a systems perspective, one that considers the policies and institutions that govern the process in which food is produced, processed, distributed and consumed, in order to ask four central questions: How and to what extent are urban produced foods reaching low income consumers, and to what effect? What are the approaches, technologies, institutions and relationships that support or detract from UA in achieving food security goals? What are the political, institutional, cultural, historical, and civic action conditions that enable or inhibit urban agriculture to address food insecurity? Lastly, How can policies be designed to support the urban farmer in earninga living wage, and support low-income consumers in accessing affordable, locally produced healthy foods? We begin by describing our literature review methodology, followed by a review of the food access and food distribution literatures as they relate to the question of how low-income communities access urban produced food. In the food access literature, we review spatial analyses and other studies that identify challenges and opportunities for expanding healthy food access in low-income communities, with a particular focus on urban produced foods. Next, we explore what is understood about the distribution of urban-produced foods especially the challenges and tradeoffs urban farmers face between securing a viable income and meeting the food needs of low-income customers.

Lastly, we bring together the literatures on access to and distribution of urban produced foods to identify effective strategies urban farms employ to meet food access needs of urban communities. Our analysis reveals three key factors mediating the effect of UA on food security: the economic realities of achieving an economically viable urban farm, the role of city policy and planning, and the importance of civic engagement in the urban food system. We seek to highlight examples from both the scholarly and gray literatures that demonstrate how UA can improve food access, distribution, and justice, in a way that supports both consumers and producers of food in cities. Results of this systematic review will guide a three-year research project to investigate and address urban food access challenges in the eastern region of the San Francisco Bay Area, where interest in UA abounds, yet levels of gentrification, food insecurity, and income inequality are growing.Our systematic review of the food access and distribution literature builds on critical food systems research in order to better understand when, where and how urban agriculture can improve food access and dismantle structures that perpetuate inequality within the larger food system. We focus on literature from the United States, in order to generate ideas relevant to the political climate surrounding city and regional planners in this country, but results are applicable for comparison or potential transferability in other countries as well. We consider both peer reviewed scholarship and gray literature from food policy organizations Urban Food Policy Institute, Detroit Food Policy Council, and Race Forward). Both theoretical scholarship and case studies are drawn out below to illustrate the question of whether UA improves food access . Building on a set of 150 articles from the researchers’ personal databases , we added an additional 200 sources from five months of Google Alerts for “urban agriculture” and from bibliographies of articles in the database. The Google Alerts provided valuable additions from new studies, local news outlets, and gray literature. In many ways, the Google Alerts service better captures current trends and innovative ideas in urban agriculture than the scholarly literature, indoor growing trays and points out important areas for future academic study, especially with respect to novel distribution methods, technology, and food recovery efforts. For example, topics such as mobile food trucks, gleaning, “agrihood” developments, participatory urban food forest projects, online food exchanges , and food distribution apps receive better coverage in local news outlets than the current body of peer reviewed literature, where these emerging ideas are largely absent. Many of the online platforms that allow farmers and backyard gardeners to sell, donate, or receive volunteer harvest assistance represent especially promising areas for future scholarly research . Farmers, Ample Harvest, or Seed Voyage.Other searches for key terms relating to food access including “food justice”, “food security”, “food sovereignty”, “food apartheid”, and “critical food geographies” added small numbers of articles to our systematic review. Terms were chosen based off keyword lists from articles in the database and results were screened for geographic relevance and mention of urban produced foods. These terms and search results bring up important questions of who prefers and uses which terms, and why.

The struggle over terminology mirrors broader struggles for control, power, and self-determination. Going beyond ‘food security’, the term “food sovereignty” originates from La Via Campesina and the predominantly rural small producers movement in the 1990s; it is applied to the urban space by scholars such as Alkon and Mares and Block et al. as a distinctly political concept that is “a transformative process . . . to recreate the democratic realm and regenerate a diversity of autonomous food systems based on equity, social justice, and ecological sustainability” . Those who use “food apartheid” aim to directly implicate the segregation that is reproduced in the modern food system and food movements with respect to who can access healthy, locally produced food along racial lines . These scholars foreground issues of race in their analyses in effort to name and dismantle racist legacies in the food system. To identify the body of literature pertaining to the distribution of urban-produced foods, it was necessary to expand our search terms beyond “urban agriculture” and “food distribution”, and start with “food systems”, “distribution”, and “urban” as key search terms. We then filtered the results of this search to exclude articles pertaining solely to location of supermarkets in fooddeserts, a common area of research but not the focus of this study . We also conducted searches for “urban foodshed” , “alternative food networks”, “informal food distribution” and “short food supply chains”, in order to track down missing literature from our collection investigating the transfers of food produced in cities. This iterative search process on the distribution side reveals the difficulties in tracking informal food distribution networks, but also the importance of doing so to better understand the real impact of urban agriculture on food insecurity in cities. Data analysis comprised content analysis of article abstracts to identify key findings among the case studies considered, and closer reading of other review articles to identify trends and gaps in the literature. Themes were extracted from articles considered, and grouped by study type to determine which types of studies provide which data.In land scarce cities striving for “best and highest use” of each lot, food production in small spaces is often considered insufficient for meeting the needs of food insecure households. To address those critics, the localized food systems scholarship offers a fair amount in the landscape ecology and planning literature theorizing the high productive potential of UA to address food insecurity . Spatial analyses such as those cited above provide insights into theoretical access, while not addressing the policy, governance and practical barriers that would need to be overcome in order to realize the potential of so many vacant lots as productive food growing spaces. There is value in spatial analyses such as these, as they offer optimal siting locations and productivity quantifications that are useful targets for planners, practitioners, and evaluators seeking to verify or ground truth theoretical projections. The optimal siting analyses, using census block group data, promote food justice by prioritizing low-income communities when siting urban farms in effort to increase access . From a global quantitative mapping analysis done with Google Earth Engine, urban agriculture was found to “positively influence food production, nitrogen fixation, energy savings, pollination, climate regulation, soil formation, and the biological control of pests, services that are worth, as a whole, as much as $160 billion” . Other theoretical mapping analyses have also found that urban and peri-urban farms can supply significant amounts of food demand in urban centers: from 5–10% of city vegetable demand supplied by expanded UA on public lands in Oakland to 30% of seasonal vegetable demand in Detroit , to 100% of nutritional needs in Southeastern Minnesota . However, very few studies directly quantify how much urban produced food is actually being consumed by low-income food insecure communities, requiring observational and qualitative research methods. Furthermore, these and other studies focus strictly on the productive capacity of UA, while there is much more being produced by UA than food alone , and the products of UA may not perfectly align with existing consumer taste and food purchasing behaviors, requiring dietary shifts that are not yet occurring . What is the spatial reality of food access on the ground? A mapping analysis of Chicago by Taylor and Lovell finds access to urban agriculture and urban-produced foods to be unevenly distributed, and household gardens correlate spatially with patterns of gentrification in Portland .

AgGuild staff are very open to the idea of supporting more farmers, both current and new, in establishing cooperative enterprises. Organic Farm School directors are similarly encouraging of this idea, arguing that many new farmers might not be ready to take over an 80-acre parcel of land and put it to productive use immediately, but it might be more appropriate for a group of five to divide up vegetable production, flower production, poultry production, grazing and value added products6. Distributing the risk, responsibilities, and knowledge-intensive labor among partners is a yet-to-be-thoroughly-tested strategy for overcoming some of the land access challenges facing farmers in the San Juan Island region.Agroecology rests upon an essential foundation of building healthy soil, through ecological cultivation of plants, insects, and food webs governed by the “Law of Return” creating a rich network of life on the farm. On Lopez, land clearing for farming, homesteading, and haying posed a threat to the island’s biological and pedologic resource base starting in the late 19th century with the arrival of European-Americans. Today, there is growing attention around restoring and revitalizing soils, forestland, and ecosystem services. Farms such as Midnight’s Farm are managing land for three purposes: healthy food production, economic viability, indoor grow trays and soil carbon storage . Other farms are following suit, seeking to build soil and revitalize land that has been degraded especially from repeated haying.

The soils on the island vary across short distances, from sandy and well-drained hilltops to heavy clay and moisture-retaining wetlands. The island geology is mostly rock, with a thin soil layer, not considered ideal for farming activities. In the words of one farmer, “we don’t have much rich farmland for row crops on Lopez, so most of us are in a constant dance to balance income-producing crops with inputs to improve the soil and, therefore, the harvest” . Farmers and ranchers are involved in a suite of soil-building practices out of necessity for maintaining productive small-scale operations year after year. These practices include compost production and application, cover cropping, biochar production and co-composting, crop rotations, intercropping , managed rotational grazing, minimal- or no-till cultivation, and combinations of perennial and annual plantings with animals to create a diverse ecological farming system that takes less than it gives back to the ultimate life-source: the soil. Farmers receive support, training, and information from researchers at WSU SJC Extension, SJICD, and through annual farmer to farmer workshops. Several farmers collaborated in 2015 to host a visit from the Soil Carbon Coalition’s Peter Donovan in order to sample local soils as a baseline and collect additional samples in later years to measure carbon storage, an important component of soil health. WSU researchers offer regular guidance and workshops around crop rotations and pasture management to improve island soils. Recently, WSU partnered with local farmers and the local bakery to host a Field Day on small scale grain production, part of a soil-building rotation that can enhance fertility in concert with legumes and other crops.

Other WSU researchers collaborated on a successfully funded Western Sustainable Agriculture Research and Education grant proposal with five local producers to explore the use of biochar co-composted with cattle bedding and other woody biomass materials as a soil amendment, which will be applied in experimental trial plots beginning in summer 2020 . The SJICD received a WA State Department of Ecology grant to purchase a no-till seed drill that is shared among islands, and recently used in a sequence of liming and seeding Lopez pastures with diverse seed mixes to restore grassland soil health. While the support and education provided by local agriculture and conservation organizations is essential, there is a constant need for further financial resources to extend and improve educational initiatives and technology pilots.Related to efforts of building healthy soil through crop rotations and appropriate farming decisions, farmers on Lopez are taking steps to provide their own inputs for crop production that do not need to be imported or purchased from off island. At a Department of Ecology-approved facility, the farm produces compost from forest and agricultural debris dropped off from across the island, grinding, composting, and screening materials in an aerated static pile system to create a finished product that is widely applied to local croplands. Manure and bedding material from the farm’s cattle, pigs, and chickens are valuable feedstocks to the composting process as well. Midnight’s produces over 600 yards of compost annually, which is all applied to Lopez agricultural lands and gardens. Farms also self-compost, recycling waste products in smaller decentralized systems and supplementing with purchased composts.

Animals also play a role: “Our pigs really close the loop for us on the farm,” one farmer stated, referring to food and plant scraps she was feeding to her American Guinea hogs who were in the midst of transforming it into high quality meat . More recently, due to wildfire risk mitigation efforts, the island has begun to selectively remove and burn some trees in a controlled, limited oxygen environment to create local biochar, a potentially valuable soil amendment with implications for increased soil carbon sequestration. Current production is happening at a very small scale, but regional interest in larger-scale biochar production abounds. Midnight’s Farm initiated a research collaboration between WSU extension, U.C. Berkeley, and five local producers from across Western Washington to address the question: can biochar be a multi-use farm product that improves farm-based co-composted products and vegetable production, and promotes soil C sequestration? Two regionally sourced biochars will be applied to cattle bedding at Midnight’s Farm, and then the biochar-bedding will be co-composted with other on-farm feedstocks to produce a biochar-enhanced compost product. Through absorbing Nitrogen and other nutrients from the cattle bedding, the “charged” biochar is intended to provide valuable fertilizer-like qualities to the compost, reducing the need for other amendments to cropping fields. The research hypotheses are: 1) blending biochar into cow bedding will result in greater N retention, reducing the potential for environmental loss, 2) adding the biochar bedding blend to compost will increase nutrient content, thereby adding value to the compost product, and that 3)compost with biochar as a feedstock will lead to increased soil carbon, cation exchange capacity, and pH when applied to soil . The research team will measure impacts on manure handling, composting, soil quality and crop yields, following field application trials on two local farms . Data will be collected in Spring 2020 on soil profiles before amendment, and again in Fall 2020 on soils and crop yields. The research underway is based on prior work from local biochar researcher Kai Hoffman-Krull and others, who have worked with universities in Washington and Montana over the past five years investigating on-farm biochar soil amendments. They have found through field trials on nearby Waldron Island, WA, that in addition to improving soil C storage, locally produced biochars have potential to “significantly improve soil fertility and crop productivity in organic farming systems on sandy soils” . However, vertical grow racks for sale there remains controversy around the impacts of biochar in disparate contexts, evidenced by several meta-analyses pointing out varied outcomes based on pyrolysis and feedstock conditions , and differential effects of in temperate vs. tropical soils . Both meta-analyses call for further study in diverse geographic contexts of interest. Pending outcomes of the local study on Lopez and across Western Washington, best practices for creating a locally sourced “complete” soil amendment could be scaled regionally, minimizing “external inputs” on a growing number of small-scale organic farms. The goal of minimizing external inputs extends from farmers to others in the food supply chain, including island bakers of Barn Owl Bakery.

Rather than purchase bulk inputs like sugar and wheat for their baked goods, Sage and Nathan are actively pursuing the local cultivation of grains and sugar beets to create their own 100% organic island grown products– sprouted Lopez wheat locally milled into flour for wild leavened breads, fruit scones, flatbreads, and weekly specialties incorporating other island grown ingredients. Their work is also supported by local researchers from WSU Extension and a Western SARE grant to understand the impact of seeding rate and fertilizer application on the agricultural performance and baking quality of landrace wheat. The goal of local input sourcing is also local waste management and reuse of waste as inputs into other ecological processes. Outputs from some farms become inputs for others, in a cost-minimizing closed-loop cycle for those involved.Transitioning food systems to agroecological practices will not be possible without investing in the “re-skilling” of an agroecological workforce. Lopez has a series of educational offerings in place to reach a variety of audiences from K-12 students to beginning and current. At the farmer-to-farmer level, Lopez farmers engage in regular meet ups and events, including the monthly farmer coffee. On the second Wednesday of each month, Lopez farmers gather at the Lopez Grange for an hour of information and resource sharing. Organized in 2019 by Faith Van de Putte, the forum is a meeting of the minds and transactional space for connecting problems with solutions, questions with answers. Where do people get good, affordable organic chicken feed? Who has straw for goat bedding? How do you get rid of persistent weeds like thistle and morning glory? Do deer get into the grain fields through the electric fence? How can we arrange for annual small animal vet clinics to provide appropriate care for our sheep, goats, and pigs? Disease and pest identification and management topics swirl around room, some finding mostly empathy, and others finding a speedier resolution. At a September 2019 coffee, several farmers shared positive results from experimenting with a new Organic Materials Review Institute -approved herbicide called “Weed Slayer,” said to be effective against the pernicious thistles. Underlying these informational exchanges is the challenge of continuing to run the iconic, diversified small farms of Lopez, lauded as beacons of sustainable agriculture and agritourism, yet requiring countless hours of hard work, determination and passion. Lopez farmers recognize that they cannot “go it alone” on their small farms and rely on the support of other farmers as well as researchers from WSU Extension. Two county extension agents were present at a recent coffee gathering to generate a list of future workshop and clinic topics to offer for farmers, as well as to gauge interest in collaborating on planned future research experiments, grants, and educational demonstrations. In addition to educating each other, Lopez farmers educate aspiring farmers primarily through the Lopez Community Land Trust Sustainable Agriculture internship program. Each year on average five interns live and work on one of the islands six main educational farms, learning from the farmer how to seed, transplant, weed, water, and regeneratively farm diverse vegetable varieties and care for animals such as chickens, sheep, pigs, and cows. These interns select several readings and a documentary to discuss with other interns under supervision from Land Trust staff. Interns complement the practical and hands-on skills of farming with bigger picture reflection and dialogue about ideal vs. real food systems, connecting the production element to all the other moving parts of the system. According to the internship program director, the three biggest takeaways for participants are 1) importance of good local food, 2) basic life skills and 3) the experience of living in community. It is an “empowering experience;” however, it is not a formal or comprehensive beginning farmer training program and has thus far not led to the transition of farmland from an aging farmer to a former agricultural intern. There are additional opportunities for young farmer mentorship through a Beginning Farmer and Rancher Development grant where more experienced farmers receive funds to support and mentor younger farmers as they begin their own operations. This is geared towards new farmers who have already taken steps to start up operations on Lopez or other islands. All farmers, new and old, have a recurring opportunity to learn more about evolving farm practices at the annual San Juan Agriculture Summit , which rotates between Lopez, San Juan, and Orcas Island, and is held in February each year. The Ag Summit began nine years ago at the impetus of the Agricultural Resource Committee and now WSU Extension has taken on the primary organizing role. Topics presented are wide ranging, from soil health to business and marketing to climate change, and feature speakers from all over the Western United States.

The climate system is also adversely impacting the food system as warming temperatures drive changes in rainfall patterns, exacerbate droughts, disrupt food distribution channels, and create extremes to which current farming practices are not adapted to coping with . However, there is potential for the food system to have a more positive set of impacts on the climate system through regenerative agricultural production systems governed by principles of agroecology. The food system has potential to re-store atmospheric carbon and rehabilitate beneficial ecological functions through re-localization and appropriate management, eventually driving more positive climate impacts back to the food system. Temporally, there is a substantial “lag time” in realizing positive climate impacts due to the 100-year residence time of atmospheric CO2;however, additional motivators for shifting towards an agroecological food system exist in the shorter-term including advancement of social, economic, health, and food justice goals.More complex representations of the food climate nexus exist showing cascading interactions between the food system, climate system, and potential adaptation/mitigation measures. The IPCC Land Use report includes a figure showing complex interlinkages between the climate system, food system, ecosystem , cannabis vertical farming and socio-economic system, operating at multiple scales, from global to regional .

Ultimately both complex and more simple diagrams are pointing towards opportunities for food systems actions to reduce and remove atmospheric GHG concentrations. However, doing so without compromising important social justice goals requires coordination and inclusive local food system planning. Debates in the agroecological food system research center around how best to achieve food systems and related social change and are discussed further in section 1.2.1 below. Emissions inventories quantify the greenhouse gas impact of food systems using various assumptions and “boundaries” between food and other sectors, such as transportation, buildings, and electricity generation. Estimates range from 8-9% of total greenhouse gas emissions attributable to “agriculture” in California and the United States , to 33% of total emissions attributable to the “global food system,” including fertilizer manufacture, food storage, and packaging . As Niles et al. state in a recent paper, “It is estimated that agriculture and associated land use change account for 24% of total global emissions , while the global food system may contribute up to 35% of global greenhouse gas emissions . As a result, food systems—not just agricultural production—should be a critical focus for GHG mitigation and adaptation strategies” . And yet, current research on climate change mitigation in the food sector focuses on the production element, without fully exploring other system elements in terms of leverage points, synergies, and tradeoffs in mitigation and adaptation efforts. It is important to consider a holistic accounting of greenhouse gas emissions from the industrial food system, including the manufacturing of nitrogen fertilizers and herbicide/pesticide chemicals; fuel for powering farm equipment; dietary preferences; and processing, packaging, and refrigeration processes, in order to optimize emissions reductions and carbon removal and maximize adaptation co-benefits of mitigating the climate crisis through transforming the food system .

Critical food systems scholars and organizations aligning with the agroecology paradigm point out several dimensions of necessary action-research to build towards a climate friendly food system, including regenerative food production, minimizing corporate influence, preventing further consolidation of corporations, promoting re-localization of food systems activities, and rebuilding a policy climate with accountable elected officials acting in the best interest of society, environment and democracy . Relocalizing food systems is credited by scholars of agroecology as “an important factor in seeking solutions to the multiple crises” that cities are currently facing, including “environment, climate change, health, social inclusion and waste management” . Agroecology scholarship spans governance scales and nations, the urban and the rural, and is best understood through the lens of the food system , weaving together production and other system elements . The agroecological food system paradigm is framed by some scholar-activists as standing in direct contrast to the dominant industrial paradigm and the Law of Exploitation; it is “centered on the Earth and small-scale farmers, and especially women farmers… ecological food systems are local food systems. The resources of the Earth… are managed as a ‘commons,’ or shared spaces for communities” . Other scholars such as Elinor Ostrom and David Bollier employ different philosophical and epistemological approaches to suggest management approaches grounded in cooperation and the commons. Ostrom famously posited eight principles for managing a commons, in direct response to Hardin’s “Tragedy of the Commons,” and she was awarded the Nobel Prize in Economics in 2009 for her efforts.

Bollier’s book “Think Like a Commoner” frames an alternative political economy, a paradigm of “working, evolving models of self-provisioning and stewardship that combine the economic and the social, the collective and the personal. It is humanistic at its core but also richly political in implication, because to honor the commons can risk unpleasant encounters with the power of the Market/State duopoly” . Bollier goes on to use words and phrases such as “bottomup, do-it-yourself styles of emancipation,” “new forms of production,” “open and accountable forms of governance,” “healthy, appealing ways to live,” and “pragmatic yet idealistic” to describe the paradigm of the commons. Inherent in both agroecology and the commons literature is the goal of returning to producers and individuals the power to self-determine systems of production and governance. Agroecological scholars increasingly engage in articulations of a vision for food system transformation, ranging from a radical overthrow of the status quo to more gradual shifts to current practices . Agroecological research is described as “transdisciplinary, participatory, and change-oriented” , and agroecology is commonly defined as a “science, practice and movement” . However, there is debate among food system scholars around how change is enacted. Some argue that agroecology is the best way to “feed the world,” and in fact, small agroecological farmers are already producing the majority of food consumed by the growing human population on a small percentage of total agricultural lands . Others argue that theland requirements of feeding a growing population through agroecological, regenerative1, and/or organic farming practices would be so large that land use change would exacerbate rather than ameliorate negative climate impacts associated with food production. These “land sparing vs. land sharing” and “feed the world debates” co-exist with debates around how to enact local food system reforms. I engage primarily with the local food system reform; my findings and contributions do not speak directly to the larger global land use and world hunger debates. Rather than arguing for radical and immediate food system revolution, the three cases presented in this dissertation illuminate opportunities for the current food system to improve along dimensions of sustainability, climate resilience, and education, presenting social and ecological benefits of local food system shifts. The cases advance an argument justifying and valorizing the existence of small farms, more easily able to provide social, ecological, cannabis drying rack and educational benefits to communities than environmentally destructive industrial farms. These benefits are not guaranteed or inevitable, however, when food systems relocalize or small farms focus on regenerative practices; they require public investment, civic engagement, and participatory action-research to sustain, safeguard, and enable their existence.Local food systems are inherently complex, social-ecological systems . Food systems researchers bring to the fore “questions such as food…nourishing bodies, soils as living organisms, urban gardens as life-sustaining infrastructure… while taking issues as money, location, skin colour, gender, and social status seriously… Food issues cannot be treated as purely socio-political, neither as mere ecological or agronomic… They are co-constructions of water, people, investment flows, soil organisms, and more. Agroecology captures this co-construction” . This excerpt nicely unites the theoretical frames of agroecology and SES, which both endeavor to explain and characterize human-nature interactions. Building a local food system requires an understanding of interdisciplinary topics and collaboration with diverse stakeholders , implicating systems of education in developing personal as well as institutional capacity for working in interdisciplinary, highly collaborative, environmentally literate teams.Piso et al.’s typology of urban agriculture distinguishes between those who are, respectively, urban agricultural stewards, risk managers, food desert irrigators, and urban agricultural contextualists. This typology can be applied to urban farms in the East Bay and has implications for how appropriate local policies might be implemented considering the local mix of farmer typologies in the East Bay agroecosystem. Overall, SES scholarship offers the reminder that “sustainability” of resource management is a collective and shifting concept, meaning different things to different stakeholders in different moments.

Therefore, the work that follows presents multiple meanings of achieving sustainability in local food systems: economic sustainability of small farming operations, social sustainability of farming as a lifestyle, and ecological sustainability of the soil resource.Environmental literacy focuses on capacity building and empowering responsible action of young people and the broader public when it comes to human-nature interactions. It is not a traditional form of “literacy,” measured by knowledge and mental aptitude alone. There is a behavioral, affective element. When facing important social-ecological challenges such as those posed by climate change and the industrial food system, environmental education and literacy offer opportunities to confront challenges through grounded knowledge of local environments complemented by awareness of global environmental realities. Knowledge alone does not inherently lead to behavior change , as climate education scholars have repeatedly shown. Pedagogies such as experiential learning are especially well suited to develop knowledge, agency, and engagement with topics in order to increase the likelihood of desired action and behavior changes. Environmental education “is set to become the largest, most effective tool in combating environmental damage and promoting sustainable development. With the planet facing the dire consequences of climate change and a global effort underway to reduce emissions…the question must be asked: How do we include the environment and sustainable development in our education system?” . Integrating environmental literacy throughout the education system is a working goal of many researchers, educators, and climate activists. Food literacy and climate literacy fall under the environmental literacy umbrella: both are more specific forms of environmental knowledge, attitudes and behaviors that deal with human relationships to the natural world, in the arenas of food production/consumption and overall planetary well being. Climate literacy is a complex and evolving topic in the literature, which simultaneously seeks to better measure it and expand the theorization of “literacy” to include informed and effective action to match the scale of the climate crisis.Within food literacy research and practice, much work has focused on the sourcing and use of local foods in school cafeterias and classrooms. The National Farm to School Network has grown in the past decade into a major driver for incorporating local and healthy foods into K-12 education. NFSN now includes 42,587 schools representing all 50 states . The Farm to School “program model” comprises three elements: school gardens, cafeteria procurement, and education, offering curriculum modules for school garden teachers to reference. Other sub-national efforts to define “Food Education Standards” for K-12 schools have more recently emerged from nonprofit organizations such as PilotLight in Chicago, IL and the Center for Ecoliteracy in Berkeley, CA. Despite the importance of the foodclimate nexus noted above, few of these food literacy efforts deal explicitly with climate change, missing an opportunity to build forms of environmental literacy synergistically. In the PilotLight Food Education Standards, produced with collaborators from Columbia’s Teacher’s College and University of Chicago, there are seven simple standards broken down into grade-specific expectations for each standard. The only mention of climate change comes under Standard 3: “Food and the environment are interconnected,” in the Grade 9-12 expectation that students “Assess the impact of climate change on food availability” . There is a gap in food and farm-based K-12 education when it comes to addressing climate change as an integral challenge and impetus for building a better food system. The gap reflects the difficulty felt by many in the K-12 education sector around teaching the topic of climate change with confidence and without controversy. The research of this dissertation fills this gap by developing and evaluating an integrated effort to build food, climate, and overall environmental literacy. Farmer-educator professional development comprises an important component of this overall process. What strategies and best practices exist for developing multiple forms of environmental literacy synergistically? Can food security and climate education challenges be resolved together?

Inspectors and auditors thus shape the ways in which growers put rules and standards into practice, yet it is very difficult to gauge their consistency and level of influence. Second, produce buyers may impose additional, case-specific production specifications on their suppliers through purchasing contracts or even verbal communication.Little scholarship has examined how these varied and dynamic pressures have played out on California farms since 2009 or assessed whether and to what extent pressures and practices vary by crop type and farm size. Several developments in the past 7 years lend urgency to the need for updated and expanded data in these areas. First, in response to the reported tension between managing for food safety and managing for environmental quality , UC Cooperative Extension in collaboration with USDA’s Natural Resource Conservation Service and others has developed guidance for and sought to raise awareness of co-management, an adaptive strategy that seeks to reduce food safety risks without impairing environmental goals . Second, the aforementioned Produce Safety Rule now requires growers to meet national standards for agricultural water, soil amendments and preventive programs to mitigate contamination risk from wildlife and livestock. Third, the ongoing drought in California and heightened water quality control regulations for agriculture — such as the Central Coast Water Quality Control Board’s Conditional Waiver of Waste Discharge Requirements under California’s 1969 Porter-Cologne Act, vertical racking system the first order that does not allow waivers for agricultural contamination to waterways — may give new impetus for growers to preserve riparian and wetland vegetation that helps reduce nutrient contamination and implement other water conservation practices.

Lastly, public health officials and media continue to draw attention to the persistent risk of foodborne illness associated with fresh produce . As these ongoing developments intensify scrutiny of field-level production, there is a pressing need to assess the current state of on-farm practices and grower perspectives for food safety and conservation. To help address the need for such data, we collaborated with the California Farm Bureau Federation in 2014 to survey growers across the state.Little scholarship has examined how these varied and dynamic pressures have played out on California farms since 2009 or assessed whether and to what extent pressures and practices vary by crop type and farm size. Several developments in the past 7 years lend urgency to the need for updated and expanded data in these areas. First, in response to the reported tension between managing for food safety and managing for environmental quality , UC Cooperative Extension in collaboration with USDA’s Natural Resource Conservation Service and others has developed guidance for and sought to raise awareness of co-management, an adaptive strategy that seeks to reduce food safety risks without impairing environmental goals . Second, the aforementioned Produce Safety Rule now requires growers to meet national standards for agricultural water, soil amendments and preventive programs to mitigate contamination risk from wildlife and livestock. Third, the ongoing drought in California and heightened water quality control regulations for agriculture — such as the Central Coast Water Quality Control Board’s Conditional Waiver of Waste Discharge Requirements under California’s 1969 Porter-Cologne Act, the first order that does not allow waivers for agricultural contamination to waterways — may give new impetus for growers to preserve riparian and wetland vegetation that helps reduce nutrient contamination and implement other water conservation practices.

Lastly, public health officials and media continue to draw attention to the persistent risk of foodborne illness associated with fresh produce . As these ongoing developments intensify scrutiny of field-level production, there is a pressing need to assess the current state of on-farm practices and grower perspectives for food safety and conservation. To help address the need for such data, we collaborated with the California Farm Bureau Federation in 2014 to survey growers across the state.The survey yielded responses from 588 produce growers who reported more than $25,000 annual sales for their operation. Of these respondents, 536 reported growing fruits and nuts and 118 reported growing vegetables and melons . About one-fifth of respondents reported growing at least some certified organic produce, with 7% reporting growing exclusively certified organic produce. To estimate our survey response rate, we compared our respondents to the subpopulation of CFBF members growing fruits and nuts or vegetables and melons, who have operations with annual sales above $25,000. When the survey was sent in 2014, CFBF had 29,519 agricultural members, 10,905 of whom were on the organization’s email listerv. Fruit and nut growers represented 41% of CFBF members on the listserv, while vegetable and melon growers represented 15%. We therefore estimate the survey instrument was emailed to 4,471 fruit and nut growers and 1,636 vegetable and melon growers. CFBF does not track its members’ annual sales. Additionally, the survey did not indicate the percentage of sales by commodity for each respondent. However, we estimate response rates by assuming that the distribution of operations by annual sales is similar between CFBF members and the full population of California growers as reported in the 2012 census of agriculture . This would mean the survey was distributed to approximately 2,618 fruit and nut growers and 684 vegetable and melon growers with annual sales above $25,000, yielding estimated response rates of 20% for fruit and nut growers and 17% for vegetable and melon growers.

The CFBF membership is not necessarily representative of all California growers, and as such our respondents should be conservatively interpreted as a convenience sample. To assess the potential selection bias resulting from this non-probabilistic sample, we compared the proportion of respondents by crop type and annual sales to the statewide proportions reported in the 2012 census of agriculture . Statewide, the ratio of fruit and nut operations to vegetable and melon operations with more than $25,000 in annual sales is approximately 9:1. The statewide ratio of produce operations with annual sales between $25,000 and $500,000 to those with annual sales greater than $500,000 is about 3:1. Among our respondents, the ratios are about 4:1 and 1:1, respectively, meaning that our sample over-represents both vegetable and melon growers and farm operations with more than $500,000 in annual sales.In our analysis, we compare respondents by the annual sales reported for their farms. Based on FDA’s definitions of farm size used in the Produce Safety Rule , we define “large” farms as respondents who reported annual sales of $500,000 or more per year and “small” farms as those who reported annual sales between $25,000 and $500,000 per year; we excluded respondents reporting sales under $25,000 per year. Different market channels represent different clusters of consumer demand, and thus may be associated with different types and intensities of food safety pressure. In our sample, respondents reporting annual sales of at least $500,000 per year also reported selling primarily to broker, wholesaler, packer/shipper and processor market channels, while respondents reporting annuals sales under $500,000 per year were more likely to report selling primarily to farmers market and community supported agriculture channels. In addition to annual sales, different crops are associated with different agronomic practices and present different food safety risk profiles. In recognition of these differences, indoor grow facility we analyze respondents who reported growing vegetable and melon crops separately from those who reported growing fruit and nut crops .The survey asked respondents to indicate when, if ever, they had used any of a list of 11 on-farm practices specifically because of a food safety concern. Respondents were also asked to indicate use of a list of 22 conservation practices on land they farm. We implemented generalized linear mixed models to assess whether and to what extent farm size and organic status affect the likelihood that a grower uses on-farm practices for food safety or conservation . Fruit and nut growers were analyzed separately from vegetable and melon growers. Predictor variables included whether growers operated a large versus small farm, and whether they grew organically versus conventionally. We first built separate models with binomial errors and logit links for each on-farm practice. We then used likelihood ratio tests to assess the significance of predictor variables, comparing nested models with and without each predictor variable .

Because each on-farm practice was modeled individually, we used false discovery rates to account for multiple tests.Most respondents reported using at least one of the 11 on-farm practices for food safety queried in the survey, with about half reporting using at least four such practices . Among fruit and nut growers , 53% reported using non-poison traps and 52% reported using poison bait because of a food safety concern. Rates were similar across organic/conventional status and farm size, although our models show that large farms growing fruits and nuts were more likely than small farms to use poison bait . A higher proportion of vegetable and melon growers reported using non-poison traps , but fewer overall reported using poison bait . However, among vegetable and melon growers , our models show that large farms were significantly more likely than small farms to report using non-poison traps and poison bait . Reported use of wildlife fences was relatively low among fruit and nut growers , but 48% of vegetable and melon growers reported using wildlife fences. No significant difference was detected across organic status or farm size for either group. Similarly, less than half of fruit and nut growers reported removing vegetation from ditches or farm ponds;large farms were slightly more likely to report removing vegetation than were small farms. The majority of vegetable and melon growers reported removing vegetation from ditches or farm ponds; no significant difference was detected across organic status or farm size. A total of 40% of fruit and nut growers and 45% of vegetable and melon growers reported clearing vegetation to create buffers; no significant differences were found across organic status or farm size. Very few respondents in either produce category reported stopping use of, draining, or filling ditches or farm ponds because of a food safety concern. One in four fruit and nut growers and 17% of vegetable and melon growers reported using copper sulfate due to a food safety concern; large fruit and nut farms were significantly more likely to report use of copper sulfate than were small farms .Most respondents reported using at least one of the 20 conservation practices queried in the survey and about half reported using at least 5 such practices . However, very few of the 20 conservation practices, when considered individually, were reported to be in widespread use . Less than a quarter of growers reported currently using constructed wetlands, vegetated water treatment systems, raw soil amendment , grassed waterways and roads, riparian restoration, bee nest boxes, or beetle banks. In addition, among just fruit and nut growers, less than a quarter reported currently using a fully composted soil amendment , heat treated soil amendments , or tail water recovery ponds. The most commonly reported conservation practice in both groups was integrated pest management , with 74% of fruit and nut growers and 80% of vegetable and melon growers reporting currently using IPM. Our models show that large farms in both groups were significantly more likely to use IPM than were small farms. Most vegetable and melon growers also reported using cover crops and crop rotation . Despite low overall use, significant differences in reported use between small and large farms were found for many conservation practices. Among fruit and nut growers , our models show that large farms were significantly more likely than small farms to use bio-control agents , sediment or stormwater basins , tail water recovery ponds , crop rotation , and physically heat-treated soil amendments . Among vegetable and melon growers, large farms were significantly more likely than small farms to use sediment or stormwater basins and tail water recovery ponds . However, among these growers , small farms were significantly more likely than large farms to use native bee nest boxes , vegetated strips for native pollinators , and fully composted soil amendments . Not surprisingly, organic growers in both categories were more likely than conventional growers to report using bio-control agents and vegetated strips for native pollinators and pest predators. Organic fruit and nut growers were also more likely than their conventional counterparts to use cover crops, crop rotation and physically heat-treated organic soil amendments.

Acceleration with multi-threading or graphics processing units is another possible direction for future research. For the second topic, there are many directions to improve the models or expand the results. Uncertainty in wind farm optimization is a major issue to address. Using uncertainty quantification to address the variability in the wind speed, wind direction, and performances of individual turbines will increase the confidence in optimal solutions. In addition, the inclusion of more models to represent the distribution of wind speeds at the rotor, tower and blade structures, rotor-nacelle assemblies, and cost models would greatly increase the fidelity of the models. More accurate wake models than the ones presented in this thesis are also under continued research, although may not be well suited for gradient-based optimization. To expand the results, more optimization studies where design variables are considered simultaneously should be considered. The computational cost of these models should also be addressed with parallelization, such as in the AEP calculation.Aquaculture is an important contributor to the Irish economy, producing products to the value of e167 million in 2016, including e105 million from farmed Atlantic salmon . Most Irish salmon farming is certified organic . Salmon farming in Ireland is associated with an intricate network of fish movements within and between the different types of salmon farms. There are three different farm types, including broodstock, freshwater, and seawater farms. In earlier work , horticulture solutions social network analysis was used in combination with spatial epidemiological methods to characterize the network structure of live farmed salmonid movements in Ireland.

It was demonstrated that characteristics of the network of live salmonid fish movements in Ireland would facilitate infection spread processes. These included a power-law degree distribution [that is, “scale free”], short average path length and high clustering coefficients [that is, “small world”], with the presence of farms that could potentially act as super-spreaders or super-receivers of infection, with few intermediaries of fish movement between farms, where infectious agents could easily spread, provided no effective barriers are placed within these farms . A small proportion of sites play a central role in the trade of live fish in the country. Similarly, we demonstrated that highly central farms are more likely to have a number of different diseases affecting the farm during a year, diminishing the effectiveness of in-farm bio-security measures , and that this effect might be explained by an increased chance of new pathogens entering into the farm environment . This is a very important area of research in aquaculture, especially considering that the spread of infection via fish movement is considered one of the main routes of transmission . Mathematical models and computer simulations offer the potential to study the spread of infectious diseases and to critically evaluate different intervention strategies . Through access to real fish movement data, these models can be programmed to incorporate both the time-varying contact network and data-driven population demographics. However, there are considerable computational challenges when stochastic simulations are conducted using livestock data, both computationally, including the need for efficient algorithms, and also with model selection and parameter inference .

An efficient modeling framework for event-based epidemiological simulations of infectious diseases has recently been developed , including the use of a framework that integrates within farm infection dynamics as continuous-time Markov chains and livestock data as scheduled events. This approach was recently used to model the spread of Verotoxigenic Escherichia coli O157:H7 in Swedish cattle . Cardiomyopathy syndrome is a severe cardiac disease of Atlantic salmon. It was first reported in the mid-1980s in farmed salmon in Norway and later detected in several other European countries, including the Faroe Islands , Scotland and, in 2012, in Ireland . CMS generally presents as a chronic disease, leading to long-lasting, low-level mortality, although some individuals experience sudden death. At times, however, CMS can present as an acute, dramatic increase in mortality associated with stress . A recent Norwegian study has identified risk factors for developing clinical CMS, including stocking time, time at sea, a previous outbreak of pancreatic disease or Heart and Skeletal Muscle Inflammation , and hatchery of origin . The economic impact of CMS is particularly serious as it occurs late in the life cycle, primarily during the second year at sea, by which time the incurred expenditure is high. No effective preventive measures are known, and there is no treatment available . In 2009, CMS was identified as a transmissible disease , and has been linked, in 2010 and 2011, to a virus resembling viruses of the Totiviridae family . The discovery of this virus, piscine myocarditis virus , has contributed to increased knowledge about the disease including the development of new diagnostic, research and monitoring tools . The agent is spread horizontally, between farms at sea, although there is some indication of a possible vertical transmission pathway .

Recent Norwegian research has shown that PMCV is relatively widespread, including in geographic regions and fish groups without any evidence of CMS . The mechanisms leading to progression from PMCV infection to CMS are currently unclear . CMS is present in Ireland. The first recorded outbreak of CMS occurred in 2012, associated with low-level mortalities over a period of 4–5 weeks followed by increased mortalities during bath treatment for sea lice . CMS is not a notifiable disease in Ireland, and there are no systematic records of its occurrence. Nonetheless, anecdotal information from field veterinarians and farmers suggest that CMS occurrence has steadily increased over the years. A retrospective study was recently conducted, using real-time RT-PCR with archived broodstock samples dating back to 2006, which suggests that PMCV may have been introduced into Ireland in two different waves, both from the southern part of the range for PMCV in Norway . PMCV was found to be largely homogenous in Irish samples, with limited genetic diversity. Further, the majority of PMCV strains had been sequenced from fish that were not exhibiting any clinical signs of CMS, which suggests possible changes in agent virulent and/or the development of immunity in Irish farmed Atlantic salmon . This paper describes the use of data-driven network modeling as a framework to evaluate the transmission of PMCV in the Irish farmed Atlantic salmon population and the impact of targeted intervention strategies. This approach can be used to inform control policies for PMCV in Ireland, as well as other infectious diseases in the future.The characteristics of the Irish Atlantic salmon have been described elsewhere , but briefly, in broodstock farms, eggs, and milt are obtained from sexually mature fish to produce fertilized eggs. In freshwater farms, fertilized eggs hatch, and fish are kept until smoltification, the stage where fish are ready to transition into the ocean . Some companies move the fish to net pens in freshwater lakes for the smoltification to occur there. After smoltification, fish are transported to seawater net pens, where they will grow until market size , with the possibility of being moved to other sea sites in between. Some of these fish are selected to become the broodstock for the next production cycle. These fish are transported from sea sites into freshwater broodstock facilities in late summer and early fall, to be stripped later in winter.These methods are based on those described by Widgren et al. . A stochastic within-farm model, linked to other farms through fish movements and local spread, was used to model the dynamics of PMCV infection in each farm. We developed a SIE compartment model with two disease states, susceptible and infected , grow benches and an environmental compartment, E. It was assumed that infected fish do not recover , and that susceptible fish can become infected through contact with PMCV present in the environment or via introduction of infected fish. To evaluate age-related differences in both the dynamics of PMCV infection within the host and in the likelihood of being moved , the two disease states, S and I, were further subdivided into three different age categories, indexed using j, including a. “egg-juveniles” from egg until 7 days prior to transfer to a marine farm, b. “smolt” from 7 days prior to the transfer to a marine farm to 180 days after the transfer, and c. “growthrepro” being more than 180 days in a marine farm. In those situations where this level of detail was not available for a particular fish group, all fish moving between freshwater farms were assumed to be egg-juveniles, and all moving between marine farms were assumed to be growth-repro. Therefore, Si,j , Ii,j , and Ei represents the six disease compartments and the environmental compartment within each farm i . A continuous-timediscrete-state Markov process with the Gillespie’s direct method, as implemented by Bauer et al. , was used to model the state transitions between the susceptible and infected compartments within each farm .

Model parameters were estimated from a previous study, which had been conducted in 2016 and 2017 to determine the prevalence of PMCV infection in Irish salmon farms by real-time RT-PCR . The sampling strategy was replicated to ascertain the status that could have been found if simulated farms had been sampled. In this study, sample collection was conducted on 22 farms from 30 May 2016 to 19 December 2017. A ranching farm is a freshwater broodstock farm that releases juvenile fish to the environment for conservation purposes. Some farms were sampled more than once over the course of the study, with the median samplings per farm in this group being 3.5 . A total of 1,201 fish were sampled during the study. Samples consisted of heart tissue across all fish age classes and ova. In this study, PMCV was detected at a low level in most sites, with only one clinical case of CMS occurring during the study period. We simulated sampling at each time point by randomly sampling fish within each farmand age category, as in the observed data set, from the number of susceptible and infected individuals at the time for the sampling point in the simulated farms. The aforementioned observational study also looked for PMCV in archived samples of Atlantic salmon broodstock from 2006 to 2016, seeking to determine whether the agent had been present in the country prior to the first case report in 2012 . For this, archived samples of broodstock Atlantic salmon were tested for each year from 2006 through 2016, using 60 archived pools per year. Samples are collected on an annual basis as part of the national disease surveillance programme, and consist of pooled organ homogenate supernatants which are then stored at −80◦C. In these samples, PMCV was first detected from broodstock fish on a marine site in July 2009, with infection in 100% of the pools . It was later detected in December of the same year in 100% of pools of broodstock fish at a second broodstock farm. These are subsequently referred to as the index cases, to be used as the starting point for simulation of the epidemic. The rationale behind setting these two farms as index cases is that they are the earliest detections , and do not seem to be epidemiologically connected. There were 9 parameters in the SIE compartment model . Following the approach used by Widgren et al. , and for model parsimony, the shed rate α was fixed at 1.0 per day, thereby defining the unit of the environmental infectious pressure variable ϕi. In the absence of more detailed data, it was assumed that the threshold for two seawater farms being connected by local spread was an euclidean distance of 10 km. It was further assumed that freshwater farms were not connected via local spread but only via fish movement.In the model, four event types were defined. “Enter” concerns hatchings and international imports. “Internal transfer” occurs on the day that individual fish change their age category, from egg-juvenile to smolt, or from smolt to growth-repro. “External transfer” occurs when fish move from one farm to another. “Exit” is linked with slaughter, euthanasia or international export, and from this point these fish are no longer included in the simulation. Each of the scheduled events was executed in the model once the simulation, in continuous time, reached the time for any of the events.

Geometric non-interference constraint functions for gradient-based optimization require special consideration. These functions must be continuously differentiable or smooth in order to be used with a gradient-based optimization algorithm. They should also be efficient to compute because optimization algorithms evaluate constraint functions and their derivatives repeatedly over many optimization iterations. During some iterations, the optimizer may violate an interference constraint, and useful gradient information on such iterations is still required despite it being infeasible. Consequently, any noninterference constraint function must be defined in the event of an overlap between objects and provide necessary gradient information.Existing non-interference constraint formulations suffer from various limitations. The formulation of quasi-phi-functions by Stoyan et al. provides an analytical form to represent an interference for simple geometric shapes. Quasi-phi-functions are continuous but only piece wise continuously differentiable. These functions are also not generalized to represent any arbitrary shape. The formulation by Brelje et al. is generalized to any triangulated 3D geometric shape, but has computational limitations. The computational complexity of their method is O, where NΓ is the number of elements in the triangulation. They are able to overcome this scaling issue by making use of graphics processing units but demonstrate their formulation on a geometric shape with only 626 elements in the triangulation. In their recent work on the WFLOP, Risco et al. formulate a generic explicit method for geometric shapes in 2D, plants rack but the method suffers from the same scaling issues as in [3] and contains discontinuous derivatives.

The formulation by Bergeles et al. employs a distance potential function that is calculated with the k-nearest neighbors. With the use of a k-d tree structure, the computational complexity of the k-nearest neighbor search scales better than linearly, O on average, but the structure is not suitable for gradient-based optimization because the derivatives are discontinuous when the set of k-nearest neighbors switches. Outside the domain of non-interference constraint formulations currently employed in optimization, we discovered a significant body of research conducted on a remarkably similar problem by the computer graphics community. Surface reconstruction in the field of computer graphics is the process of converting a set of points into a surface for graphical representation. A popular approach for surface reconstruction is the representation of surfaces by an implicit function. Implicit surface reconstruction methods such as Poisson, Multi-level Partition of Unity, and Smooth Signed Distance, to name a few, construct an implicit function from a point cloud to represent a surface. We observed that some of these distance-based formulations can be applied to overcome prior limitations in enforcing geometric non-interference constraints in gradient-based optimization. The first objective of this thesis is to devise a general methodology based on an appropriate surface reconstruction method to generate a smooth and fast-to-evaluate geometric non-interference constraint function from an oriented point cloud. It is desired that the function locally approximates the signed distance to a geometric shape and that its evaluation time scales independently of the number of points sampled over the shape NΓ. The function must also be an accurate implicit representation of the surface implied by the given point cloud. The contribution of this paper is a new formulation for representing geometric non-interference constraints in gradient-based optimization.

We investigate various properties of the proposed formulation, its efficiency compared to existing noninterference constraint formulations, and its accuracy compared to state-of-the-art surface reconstruction methods. Additionally, we demonstrate the computational speedup of our formulation in an experiment with a path planning optimization and shape optimization problem. This section, in full, is currently being prepared for submission for publication ofthe material. Anugrah J. Joshy, Jui-Te Lin, C´edric Girerd, Tania K. Morimoto, and John T. Hwang. The thesis author was the primary investigator and author of this material.Wind energy is a sustainable method for electric power generation that mitigates greenhouse gas emissions from other power generation resources, such as with fossil fuels. Predictions show that the climate change mitigation from wind energy development ranges from 0.3◦C to 0.8◦C by 2100. Off-shore wind farms can also mitigate the impacts of hurricanes for coastal communities. As such an impactful energy resource, the field of wind farm optimization has gained recent attention to maximize the energy production and economic feasibility of developing wind farms. The increased adoption of multidisciplinary design optimization techniques by the wind energy community has produced many recent works including the optimization of wind turbine designs, wind farm layouts , and active wind farm control. In general, turbine design, wind turbine layout, and active turbine control strategies are the three main methods to increase wind farm efficiency by reducing the wake interaction between turbines. Although these methods individually may increase the net efficiency, it has been shown that considering multiple or all three methods can further the a more optimal model. Recent simultaneous optimization studies include control and layout optimization and turbine design and layout optimization. Numerical optimization, as an important design tool to solving these problems, has been widely used for wind farm optimization. Gradient-based and gradient-free algorithms are the two main algorithms to perform optimization. Historically, gradient-free algorithms have been used for wind farm optimization problems due to the high multi-modality in the design space of these problems.

Gradient-free optimizers are robust to local minima, while gradient-based optimizers often converge to a local optima. However,as these problems increase in scale and the number of disciplines, the dimensionality of the design space may become impractical for gradient-free optimization. Gradient-free optimizers scale poorly in the number of function evaluations as the number of design variables increase in these complex wind farm problems. Gradient-based optimization, especially with analytic gradients, scales better in the number of function evaluations over gradient-free optimizers in these cases. In addition, recent developments have added methods for gradient-based optimizers to navigate the multi-modal design space of these problems. As a result, gradient-based optimization continues to play a key role in optimizing wind farms. When modeling wind farms for gradient-based optimization, it is important to consider the computational speed and differentiability of the models. High fidelity models are often very computational expensive to evaluate, and these models must be evaluated up to hundreds of times during optimization. Therefore, lower fidelity models that are less computationally expensive are often considered for use in gradient-based optimization. Additionally, the differentiability of the models is a requirement in order to perform gradient-based optimization. The ability to calculate derivatives within the model has not always been readily available. Oftentimes, significant effort must be made to hand derive the derivatives, or in the worst case, using the finite difference method for derivatives, which is on the same order of function evaluations as gradient-free optimization. Current state-of-the-art gradient-based optimizations are performed using automatic differentiation, however it still requires a level of effort to implement into new models, especially when local smoothing techniques are required. A notable research problem in wind farm layout optimization is the representation of wind farm boundary constraints. Boundary constraints in wind farm layout optimization prevent the placement of a wind turbine on regions outside of the permitted zone. Examples of exclusion zones for off-shore wind farms include unsuitable seabed gradients, shipwrecks, and shipping lanes. These zones are often disjoint, non-convex, plant growing trays and highly irregular shapes represented in 2D. There exists a lack of a generic method to represent these boundaries in the wind farm optimization community. Additionally, the state-of-the art methods suffer from the same problems noted in Section 1.1, where the computational complexity scales with the number of points representing the polygonal wind farm boundary. Conveniently, the first contribution of this thesis addresses this issue. The new geometric non-interference constraint formulation provides a smooth, differentiable, and fast-to-evaluate constraint function that represents the wind farm boundary suitable for gradient-based optimization. Another tool that may show to benefit gradient-based wind farm optimization is a new modeling code language called the computational system design language. CSDL is an algebraic modeling language for defining numerical models that fully automates adjoint-based sensitivity analysis. Additionally, CSDL contains a three-stage compiler system that constructs an optimized computational graph representation of the models. As a new design language, it shows potential to improving the convenience and speed of developing the models to perform gradient-based wind farm optimization. The second objective of this thesis is to implement the two aforementioned tools–the geometric non-interference constraint formulation and the computational system design language –and perform optimization studies on multiple wind farm optimization problems. We conduct optimization studies on turbine hub heights, turbine yaw misalignment, and wind farm layout, and investigate their properties as it pertains to gradient-based optimization.

These three problems demonstrate the potential of gradient-based optimization in turbine design, wind farm control, and wind farm layout optimization problems. Using well know analytical models, we conduct multiple optimization studies using CSDL as a modeling paradigm and verify its accuracy with other industry-leading optimization frameworks. Additionally, we perform a wind farm layout optimization with a real-world wind farm, highlighting the accuracy and efficiency of the geometric non-interference constraint formulation.We identify two preexisting methods for enforcing geometric non-interference constraints in gradient-based optimization that are both continuous and differentiable. Previous constraint formulations that utilize the nearest neighbor distance, e.g., Risco et al. and Bergeles et al., have been used in optimization, but we note the that they are non-differentiable and may incur numerical difficulties in gradient-based optimization. Brelje et al. implement a general mesh-based constraint formulation for noninterference constraints between two triangulations of objects. Two nonlinear constraints define their formulation. The first constraint is that the minimum distance of the design shape to the geometric shape is greater than zero, and the second constraint is that the intersection length between the two bodies is zero, i.e., there is no intersection. A binary check, e.g., ray tracing, must be used to reject optimization iterations where the design shape is entirely in the infeasible region, where the previous two constraints are satisfied. As noted by Brelje et al., this formulation may be susceptible to representing very thin objects, where the intersection length is very sensitive to the step size of the optimizer. Additionally, the constraint function has a computational complexity of O, which may be addressed by the use of graphics processing units . Lin et al. implement a modified signed distance function, making it differentiable throughout. Using an oriented set of points to represent the bounds of the feasible region, the constraint function is a distance-based weighted sum of signed distances between the points and a set of points on the design shape. This representation is inexact and is found to compromise accuracy for a smoothness in the constraint representation in practice. Additionally, their formulation has a computational complexity of O.Our first objective—to derive a smooth level set function from a set of oriented points—closely aligns with the problem of surface reconstruction in computer graphics. Surface reconstruction is done in many ways, and we refer the reader to for a full survey on surface reconstruction methods from point clouds. We, in particular, focus on surface reconstruction with implicit function representations from point clouds. Implicit surface reconstruction is done by constructing an indicator function between the interior and exterior of a surface, whose isocontour represents a smooth surface implied by the point cloud. The methodologies for surface reconstruction use implicit functions as a means to an end; however, the focus of our investigation is on the implicit function itself for enforcing non-interference constraints. We identify that the direct connection between non-interference constraints and implicit functions in surface reconstruction is that the reconstructed surface represents the boundary between the feasible and infeasible region in a continuous and differentiable way. Geometric non-interference constraints may be represented by geometric shapes using scanned samples of the surface of an anatomy, outer mold line meshes, user defined polygons, and a sampled set of points of seabed depths. Many geometric shape representations, including those mentioned, can be sampled and readily converted into an oriented point cloud and posed as a surface reconstruction problem. The construction of any point cloud comes with additional complexities. For example, machine tolerance of scanners introduce error into scans, and meshing algorithms produce different point cloud representations for the same geometric shape. As a result, implicit surface reconstruction methods often take into consideration nonuniform sampling, noise, outliers, misalignment between scans, and missing data in point clouds.

In leaves, the upregulated and downregulated SlARF6A transgenic lines possessed higher and lower chlorophyll levels, respectively, than the WT plants . Then, chlorophyll autofluorescence in the pericarp was detected using confocal laser scanning microscopy. OE-SlARF6A plants had stronger chlorophyll auto- fluorescence, while the RNAi-SlARF6A lines had weaker chlorophyll autofluorescence in both epicarp and endocarp tissues compared with that of the WT plants . Then, the chloroplasts were observed using a transmission electron microscope . The growth of individual chloroplasts in OE-SlARF6A fruits was obviously promoted, with a significant increase in size and length . However, the number of chloroplasts per cell in OE-SlARF6A fruits was the same as that in the WT plants. For the RNAi-SlARF6A lines, the number of chloroplasts per cell was obviously decreased, but the size of individual chloroplasts was not changed .The name stone fruit refers to the stone-like pit encasing the seed. It is the soft, flavorful, juicy, aromatic , mouthwatering combination of sugars and acids in fleeting succession that intrigues us as gardeners. The true “raison d’etre” for these swollen ovary walls is merely to attract animals to eat them and disperse the seed to perpetuate the species. After much field testing and reflection, I would say of this evolutionary strategy — Well done, well done indeed! The stone fruits are nonclimacteric fruits. Climacteric derives from the Greek root meaning “critical point,” or literally, “rung of a ladder.” It is therefore a major turning point or critical stage — in this case, pre-senescence or death. Climacteric fruits such as apples and pears, bananas, kiwis, weed drying room and avocados can be picked mature but green, held under refrigeration, and will ripen and color on their own, or with the introduction of ethylene gas.

These fruits store their sugars in the form of starches that are converted back to sugars by enzymes and by warm temperatures off the tree. Nonclimacteric stone fruits don’t produce or respond to ethylene gas. They ripen gradually, and don’t store sugar as starch, but instead depend on their continued connection—via the conductive vascular tissue of the stem—to the parent for continued sweetening. They get no sweeter off the tree, though enzymes may promote their softening. Thus the quality of the fruit is dependent on the ripening that takes place on the tree. In fact, cold storage retards natural pectin breakdown, causing stone fruits to become dry and mealy.Peaches and nectarines hail from northwestern China . The specific name persica is a misnomer, probably attributed to its spread via trade caravans from China into Iraq and Iran and eventually to Europe. The fruit came to the Americas with the Spanish explorers in the 16th century on their conquering expeditions. It was then spread across the U.S. by Native Americans. The nectarine is genetically identical to the peach but with a recessive gene for pubescence . The nectarine is as old as the peach, with records of cultivation dating back to 2,000 BC. It is either a chance seedling or a whole tree mutation . Commercially, peaches and nectarines are grown at latitudes between 25º–45º North and South of the equator. Major peach growing regions include Chile, China, Northern Italy, Spain, Turkey, California, Southeastern U.S., New York, Pennsylvania, and Michigan. They can be grown closer to the equator than any other species of temperate zone deciduous fruits because of their tolerance for heat and humidity, and their low chill requirements for breaking dormancy. The peach, often referred to in old pomology texts as the “Queen of Fruits,” ranks only behind the apple in worldwide production and economic worth. Their sweet flavor, aroma, and nectar set the bar very high for sun-warmed tree-ripe perfection that evokes the essence of summer.

Peaches are the shortest-lived of all deciduous fruit trees, with an average life expectancy of only 20–40 years . Because the genetics of the peach are much less variable than any other fruit, the trees of almost every seedling bear edible fruit. There are also more cultivars of peaches than any other fruit owing to the ease of obtaining quality seedlings from peach crosses. Peaches and nectarines can be grouped into two basic flesh types—clingstone and freestone. Clingstones exhibit a firm-textured flesh that cannot be pulled off the stone and must be cut away with a knife. Because they hold their shape when cut or sliced, they are the logical candidates for canning, drying, or being used fresh, halved, or sliced. Freestones are softer-fleshed varieties with higher juice content, and separate easily from the pit. They lend themselves to fresh eating.Additionally, peach tastes can be linked to flesh color and “old school” vs. “new school” varieties. Old school varieties don’t color evenly or have as bright a sheen to their skin. They have a more balanced sugar/acid ratio contributing to a fuller old-timey peach flavor. They have a very limited shelf life, must be tree ripened to have full flavor, and bruise easily, giving rise to that old farmers’ market adage, “Real peaches don’t stack.” These “old school” varieties include Suncrest, Elberta, Babcock, J.H. Hale, Red Haven, Le Grand, Rio Oso, Sun Grand, and Baby Crawford . Because they are more difficult to grow they’re considered all but obsolete in today’s produce world. And because the fruit deteriorates rapidly in cold storage, the older varieties are a mere remembrance fading in the rear view mirror—a tribute to a time when there was a fierce loyalty to varietal brand names. New school peach and nectarine varieties are all sugar and sweetness with very little acid. They have a rich pink/red hue to their skin, are firm fleshed, larger on average than the old varieties, and continue to ripen off the tree under refrigeration. They have a sublime, delicate flavor that is less peachy and more sugary. New school varieties include Arctic Supreme, Arctic Glo, White Lady, Sugar Lady, Snow Giant, and Arctic Jay . In general , white-fleshed varieties are sweeter than the more sugar/acid balanced, aromatic, yellow-fleshed varieties. A separate category of peaches, including Peento, Donut, Saturn or Bagel peaches , are synonyms for the smallest, sweetest, melting-fleshed peaches native to China. They are flat, small , and shaped like their name implies. They have a very short season and bruise more easily than any other type of peach.The peach is a vigorous upright grower in the early years after planting. As it matures the tree’s habit morphs to a more naturally spreading form with moderate to weak vigor. Peach leaves cast dense shade, so it is important to train trees to allow sunlight to penetrate into the center of the tree. Remember, sunlight translates to color and emphatically to high sugar content. The largest, best-quality peaches are produced on lateral one-year-old branches that hang on young, actively growing main scaffold branches . With peaches, drying rack for weed what you grew last year is what you’re eating this year. That is to say that a lateral branch will grow one year and simultaneously produce and express fruit buds. In year two these branches bear fruit. They should be shortened to 12–18 inches long and fruit should be thinned to 6–8 inches apart. Because peach fruit buds contain only a solitary flower, they set a single fruit and unlike apples don’t need cluster thinning. Proper thinning equals proper size and is especially critical on small-fruited varieties like Saturn types, Baby Crawford, and all nectarines . In the third year, the lateral shoot will die out and not bear any fruit.

Or it will grow new wood that bears the following year, but is too far away from the main branch for either good mechanical support or continued flow of nutrients for size and taste. In any given winter pruning session, approximately one half the laterals should be stubbed to 1–3 buds or 1–3 inches to renew growth and bear the following year. Similarly, after laterals have fruited they should be stubbed back to renew the cycle. Since new growth is prioritized on peaches and nectarines, primary branches are pruned hard annually in the winter to encourage good extension growth and the induction of laterals. As a result, it is not unusual to prune 40–60% of the previous year’s total growth off a peach or nectarine . Additionally the primary scaffold branches on an peach are completely renewed by stubbing them to their base every 5–7 years. This re-scaffolding is best achieved incrementally over a 3–5 year period. More markedly than with pome fruits, peaches slow down and lose vegetative vigor with age. Almost all peach/nectarine varieties are self fruitful, that is they accept pollen from their own flowers and do not need pollen from another variety to set fruit. Notable exceptions are Elberta types and Hale cultivars. Peach leaf curl is a leaf fungus that afflicts almost all peach and nectarine varieties in almost all growing regions. It is especially devastating in cool, coastal climates where trees can be completely defoliated in June during a bad year. Peach leaf curl infects the leaves and young shoots. It causes distorted, reddened, puckererd foliage and when severe can radically reduce annual production and deinvigorate the tree over the long term. As with most pest and disease populations, the aim in controlling peach leaf curl is to aggressively prevent high spore pressure. It is difficult to work backward from high pressure to good control organically. An easy-to-remember schedule aligns with three big American holidays: Thanksgiving , Christmas and of course the Super Bowl . Resistant peach varieties include Frost, Avalon Pride, Mary Jane, and Q1- 8. Extremely susceptible but great tasting varieties include Babcock, Elberta, and the Saturn types.Compared to pome fruits, rootstock options are more limited with stone fruits. There are no truly dwarf stocks—the only choices are full-size and semi-dwarf. The principle attributes imparted to fruit trees via rootstocks are size control, disease/pest resistance, and fruiting efficiency. Size Control – Full-size or standard stocks produce vigorous vegetative growth . Trees on these stocks will top out at 20–30 feet tall. Semi-dwarfing stocks reduce tree size . Pest, Disease Resistance – The main issue with stone fruits is root susceptibility to nematodes , which are multicellular, microscopic non-segmented roundworms. Nematodes sap tree roots of nutrients, reduce vigor, and lower fruit productivity. The rootstocks Nemaguard and Nemared impart resistance, especially with peaches and nectarines. Fruiting Efficiency – Although not as dramatic as with pome fruits, stone fruit dwarfing rootstocks promote greater fruit production per area of tree canopy. The mechanisms for this are not fully understood, but the result is demonstrable.These are the plums of choice throughout Europe, more widely planted than apples and pears. In the Slavic countries Domestica plums exceed 50% of all acreage planted to fruit trees. There is evidence of Domestica plums being grown in Europe prior to 2,000 years ago. Commonly dubbed prune plums in the U.S., European plums offer a more diverse spectrum of colors, shapes, sizes, tastes, and uses than any other fruit. The fruit is small and oval-oblong—almost egg shaped. Skin colors are in the blue-purple range for prune types to yellow, orange, and red for dessert types. They thrive in areas with moderate summers , low humidity and moderate winter chill. Major production areas worldwide include Western U.S., New York state, Italy, Chile, Turkey, Romania, Yugoslavia, France, Austria, and Germany. The trees of European plums are upright and vigorous when young and develop a pendant weeping form and weak vigor when established. At 50–80 years they are fairly long-lived. The fruit buds are the longest lived of the stone fruits , so minimal renewal pruning is necessary. They tend to be a shorter tree than Japanese plums . European plums also have a higher chill requirement to bloom and set fruit and bloom later than their P. salicina counterparts, and in some years avoid the pollination problems caused by erratic spring weather and rain. They are self unfruitful and thus need pollen from another variety to set fruit. The varieties Santa Rosa and Wickson are universal pollinators. European plums are smaller and firm textured, with less juice than Japanese plums. They are also free stone. Because of their high sugar content they dry readily as prune plums. Fresh off the tree, European plums are a high quality dessert fruit and because of their low juice content and freestone nature, are excellent candidates for cooking in tarts and other recipes.This species, known as the gage plums, originated in Turkey and was brought to Mediterranean Europe by the Romans.

Porcine reproductive respiratory syndrome emerged in the U.S. in the late 1980’s and since then the disease has been prevalent in the country. The causative agent of PRRS is a highly mutant RNA-virus with two main linages, genotype 1 and genotype 2 , which is resilient to low temperatures and hence adaptable to the US Midwest, where most of the US swine industry is located. High animal density, the use of live PRRSV vaccines, collection of dead pigs rather than incineration, early weaning age, and close proximity to or frequent contact with infected premises, also referred as farms, are factors suggested or demonstrated to promote PRRS spread. While the only natural host for PRRSV is pigs, the sources of spread include direct and indirect contacts between infectious and susceptible animals. Because PRRSV can be excreted via multiple fluids facilities and vehicles used for pig transportation may be contaminated, contributing to disease spread within and between regions. PRRS imposes more than $550 million in losses annually, increasing prices to consumers. Furthermore, within a global environment where the US swine industry competes with producers in other countries and with other sources of meat, e.g., beef and poultry, profitability is reduced for the industry. The World Organization for Animal Health has listed PRRS as a “notifiable terrestrial animal disease” , and the US has reported the presence of PRRS in the country. However, since it is considered a production disease, daily reporting is not mandatory and implementation of control activities are voluntary. Several diseases, such as classical swine fever or Aujeszky’s disease, have been eradicated from the US by implementation of official programs and by means of agreements reached among different levels of decision-makers. Because PRRS has become endemic in the US , in the absence of an official regulatory framework, regional strategies are emerging to control the disease. One initiative, led and funded by swine producers and supported by the University of Minnesota, curing cannabis was launched in 2004 with approximately 90 premises in Steven County, MN. It evolved into what may have been the first regional control project in the US. This RCP is referred to as the N212 Minnesota Voluntary Regional PRRS Elimination Project .

In 2014 it has expanded to include swine producing premises in 39 counties in MN. The RCP-N212 initiative was followed by others and currently there are more than 30 RCPs, also referred as area regional control projects or ARCs, throughout the US and Canada, including, RCPs in Southeast Iowa, Western Michigan, Northwest Indiana, and Pennsylvania. RCPs promote communication among producers regarding disease prevalence and efforts to control it, with the expectation that such information will lead to the development and adoption of strategies for disease control within a geographical area. RCPs function through the voluntary participation of swine producers who enroll in the program and who agree to share the disease status of their farms. As an incentive to participate, participants receive an exclusive, weekly report of regional disease status. RCPs initially focused on PRRS, but more recently have also included porcine epidemic diarrhea. RCP programs have, arguably, strengthened the US swine industry by encouraging communication between and among producers and research institutions. However, few evaluations ofRCP goals and achievements have been carried out. This paper proposes a methodological framework to evaluate the progress of an RCP, using data collected at the RCP-N212 for years 2012–2014. We analyzed demography of premises, disease communications, short-term trends in PRRS incidence, and disease distribution, based on information shared by participants. We anticipate that established benchmarks will facilitate comparisons among RCPs and the establishment of control objectives.This paper used a confidential dataset with information collected from July 2012 to June 2014 of swine premises enrolled in the RCP-N212 , and public sources with information to account for the total number of premises per county and area per county. The RCP-N212 dataset contained information at premises level including geographical location, day in which premises was enrolled in the RCP-N212, type of premises, and PRRS status.

Type of premises indicates the phase of swine production, e.g., farrow-to-wean, wean-to finish, finishing, etc.. In this study, for simplicity, premises that have breeding herds or sows were referred to as sites with sows , whereas premises without sows were referred to as sites with no sows . Participating producers are requested to report any PRRS status changes to the coordinator of the RCP-N212 as soon as it occurs, i.e., within a day. Additionally, at least once a month, the coordinator directly contacts producers to obtain a PRRS status update for their farm. Premises that voluntarily share PRRS status were categorized following the American Association of Swine Veterinarians guidelines. Briefly, the AASV guidelines assign to SSs one of five mutually exclusive status categories: 1, 2A, 2B, 3 and 4. Positive unstable indicates virus detection in the premises and clinical signs compatible with PRRS. Positive stable are premises in which breeding herds are PCR positive but do not present clinical signs of PRRS and weaning pigs have passed at least four consecutive PCR negative tests, one every 30 days using a sample size of 30 weaning pigs, to demonstrate lack of viremia. This category is divided into two subgroups: 2A for SS that are not undergoing elimination, and 2B for premises undergoing elimination of PRRS. In the latter, at a certain point in time, neither vaccinations nor exposure to the live virus to achieve immunity is allowed, and additional restrictions on cross-fostering and herd access to replacements are applied. Provisional negative denotes a premises that is continuously introducing negative replacement gilts, with results of ELISA negative for breeding herds after 60 days of introduction. Negative indicates consistently negative results to serologic and PCR testing. For NSSs AASV guidelines assign one of two mutually exclusive status categories: Positive , similar to category 1 for SSs, and negative in which the premises must have ELISA negative results in growing pigs. RCP-N212 dataset was protected on a codified database at the University of Minnesota. From an analytical perspective, this study may be regarded as an observational, longitudinal, retrospective cohort study.First, demographics of the RCP N212 were measured by the monthly proportion of premises enrolled, using the number of premises enrolled per county as numerator and the total number of swine premises per county as denominator. Then, among premises enrolled in the RCP-N212, a repeated measures analysis of variance was used to assess changes in the proportion of premises types over a 24-month period.Although the proportion of premises enrolled slightly decreased over the study period, both the number of enrolled premises and the geographical coverage of RCP-N212 increased from 427 premises in 34 counties in July 2012 to 500 in 39 counties in June 2014 . Among premises enrolled, the proportion of SSs and NSSs did not change significantly , through time, but proportions between SSs and NSSs were statistically different , ranging from 0.23 to 0.24 for SSs and from 0.76 to 0.77 for NSSs. The most parsimonious mixed-effects logistic regression model contained time and type of premises as fixed effect, using premises ID nested by county as random effects. Final results suggested a significant increase of active participation in RCP-N212 over the 24-months period . The monthly increase in the odds of sharing PRRS status by premises was 4.2 , although NSS enrolled premises were less prone to report than SS enrolled premises . There was a larger variability in the observed participation data between than within counties, as demonstrated by the estimated random effects . The normal time-space scan test identified 2 significant clusters of high and low probability of sharing PRRS status, compared to the expected null hypothesis of an even distribution of cases in the assessed area . The cluster of high-probability of sharing PRRS, located in the northern area of the RCP N212 , cannabis dryer was detected at the second half of the study period , whereas the low probability cluster was located in the southern area in the RCP N212 in the first half of the study .Among premises enrolled that shared PRRS status , 175 outbreaks of PRRS were reported in 168 premises during the 24 months of the study period. This roughly represents 35% of all enrolled premises and 44% of premises that shared PRRS status .

The univariate logistic regression analysis indicated that time, probability of sharing PRRS status , type of premises, proportion of stable premises in the county, and density of premises in the county showed a p-value <0.25 in their associations with PRRS incidence and were consequently incorporated and tested in the multivariate mixed effects models.However, the most parsimonious mixed-effects logistic regression model contained only time, probability of sharing PRRS status, and density of premises in the county as fixed effects, whereas premises ID nested into county was included as a random effect. A significant monthly decrease of odds of PRRS incidence was identified . The probability of sharing PRRS status was negatively associated with PRRS incidence , whereas the density of big and medium-sized premises in the county was positively related with PRRS incidence . Significant temporal aggregations of incidence of PRRS were observed over the study period, and at the same time a decreasing trend on temporal densities was detected . This result suggest that PRRS incidence was grouped in time, as an initial outbreak increases virus shedding within a region, which leads to disease spread, but that leads to a corresponding increase in disease control, resulting in a decrease in shedding and spread. The probability of outbreaks is trending down slightly over the period. At the same time, and coincidently with temporal manifestation of PRRS, spatial aggregation in a number of locations, mainly in the mid-western region of the RCP N212 was revealed . In turn, cluster for the spatio-temporal point process given by KST > πu2 v was consistent with findings by pair correlation function.Results of this study demonstrate the application of a systematic approach to assess the evolution of RCPs. We have demonstrated that farmers’ enrollment in a voluntary regional control program is not necessarily an accurate estimate of participation, as farmers may enroll, but not share information on disease status, which may be critical in PRRS control. Results on organization of the RCP-N212 program and on PRRS control are encouraging. While 40% of those enrolled in July 2012 did not share information, this figure went down to 20% in June 2014. Although active participation did not reach 100% among premises enrolled in the program, the statistical increase in sharing PRRS status suggested a growing interest of participants to share disease status. This information was incorporated in a regression model, which suggested a significant negative relationship between probability of sharing disease status and PRRS incidence in the RCP-N212. In 2014, premises enrollment had reached 34% of all premises in the counties included in RCP-N212. NSSs account for roughly three quarters of all enrolled premises , but the principal strategies to control PRRS are focused on SS premises, which attempt to ensure that only PRRSV-negative pigs are weaned. In areas in which premises density is high, immunization of the population through vaccination or live-virus exposure has been the preferred control strategy leading premises to stay in AASV category 2A, whereas in regions with low premises density, undergoing elimination of PRRSV is preferred. However, despite the relevance of upstream PRRSV control for maximizing returns at the system level, status of PRRS in NSSs is also important if the objective is to control the disease at a regional level, due to their potential importance of NSSs as sources of infection. The above may be particularly important in controlling PRRS at a regional scale, in which a large proportion of the premises present might be NSSs, as is the case for the RCP-N212 where direct and indirect contacts due to exchange of inputs between NSS-NSS, SS-SS and SS-NSS might facilitate transmission dynamics of PRRSV. Considering all premises located in counties in the RCP-N212, active participation increased from 22% in July 2012 to 27% in June 2014 . While only about 60% of enrolled premises shared information in 2012, 80% shared in 2014, suggesting a significant increase in willingness to participate among producers . However, the extent at which information was effectively shared was heterogeneous in premises type , time, and space.