UC Santa Cruz

One of the most pressing global challenges considers how to combine sustainable agricultural land use with biodiversity conservation. Traditional agricultural systems have been dramatically transformed and intensified, leading to the simplification of agricultural landscapes through increased agrochemical use, landscape homogeneity, decreased crop diversity, and mechanization. Each of these activities restructures the physical and social environment in which food systems are embedded. Market motivations overlook ecological costs, including the loss of habitat complexity, functional biodiversity, and related ecosystem services, such as biological pest control, as well as socio-cultural costs, such as the erasure of traditional agroecosystems. In my dissertation I explore how socio-ecological complexity informs coffee farm management, habitat complexity, and subsequent outcomes for biodiversity, ecosystem services, and equitable supply chain governance. My ecological work draws on theoretical frameworks from population, community, and landscape ecology to explore relationships between biodiversity and ecosystem services, such as pest control. First I examine how vegetation connectivity (e.g., branches, epiphytes, lianas, spontaneous weeds) impacts ant-mediated control of the coffee berry borer (Hypothenemus hampei, CBB), the major insect pest of coffee in Chiapas, Mexico. My findings demonstrate that vegetation structure influences the relative abundance and activity of a native, dominant predatory ant species, Azteca sericeasur, with cascading effects on pest suppression. Naturally occurring vegetation connectivity increases ant activity, resource recruitment, and ant-mediated biocontrol of the CBB, whereas artificial connectivity (twine) supplements ant activity and biocontrol, but is not as effective as, vegetation connectivity. I then apply these findings to a novel coffee system in Hawai'i, where the CBB only recently invaded, and there are no native ants. I demonstrate that diversity of ground cover and shade trees, together with climate variables, determine ant richness and abundance, impacting ant-mediated CBB removal and CBB pest damage to coffee fruits. Together, Chapters 1 and 2 illustrate that management conducive to forest conservation and habitat complexity, along with associated vegetation connectivity, maintains the relative abundance of beneficial species and interspecific interactions that facilitate top-down control of a key coffee pest. In Chapter 3 I draw from agrarian political economy and food systems governance frameworks. Through event ethnography and interviews with over 40 stakeholders across the Kona coffee supply chain, I reveal how power dynamics dictate whether and under what circumstances value chain governance arrangements, including Geographic Indications, act as policy tools that serve or fail smallholder coffee farmers. My findings demonstrate that a farmer-backed Hawaiian coffee bill (House Bill 2298), mandating 51% “Kona coffee” was driven by a convergence of farmer organizing, legal wins, technological shifts, and present consumer demands. Yet, even in this apparent “farmer success story,” producer power through GIs remains unevenly distributed, temporally limited, often dependent on vertical integration, and continually threatened by the concentrated buyer power of the supermarket oligopoly. Overall, my dissertation integrates ecological experiments and political-economic analysis to reveal both social and ecological drivers that shape coffee landscapes. My work contributes to a growing body of research demonstrating the importance of biodiversity and habitat structure for supporting functioning agroecosystems, including the ecological interactions that maintain biocontrol. This research confirms previously established knowledge about the role of biodiversity in biocontrol while extending these insights to habitat structure and a novel agroecological context. Finally, using Kona coffee as a critical case, I advance our understanding of farmer empowerment through GIs by identifying conditions under which smallholder farmers successfully reshaped GI governance; the rarity of these converging conditions also demonstrates why farmer empowerment through GIs remains difficult to achieve and sustain.