From early cultivators to the Green Revolution, agriculture has dramatically impacted the environment and human society, fostering our ecological dominance and generating the Anthropocene era. As we now approach crossing multiple planetary boundaries, ensuring food systems sustainability is ever more critical. Diversified, agroecological farming systems present potential solutions to increasing food production while also sustaining soils, water, biodiversity, livelihoods and cultures; however, many sociocultural and economic barriers impede their adoption. We present a conceptual, methodological, and analytical framework for integrating social and ecological data from on-farm research with 27 organic farms in California’s Central Coast region. These farms employed a range of “diversification practices” within varied cropping systems and surrounding landscapes. Some farms, for example, grew only the focal crop (strawberry) and used few diversification practices; others grew many crops using multiple diversification practices. We measured various ecosystem services on the focal crop, and surveyed biodiversity indicators on both focal and non-focal cropped areas of the farm. We conducted in-depth, semi-structured qualitative interviews with farmers to assess their perceptions and experiences of diversification practices, and subsequently developed Markov Decision Process (MDP) models to describe the socio-ecological system and compare model predictions against empirical data.
Results/Conclusions
Initial qualitative results indicate that highly-diversified farmers identify numerous non-commodity benefits motivating them to adopt diversified practices, including grower satisfaction with adopting innovative approaches. However, farmers also experience key barriers to implementation, including labor shortages, food safety standards, and unreliable access to land. Initial ecological results suggest tradeoffs between landscape and local-scale diversification for ecosystem services. For example, greater landscape diversification decreased pest bird incidence and bird damage to strawberries, while local-scale diversification increased these factors. Both scales of diversification promoted bird biodiversity overall. Under linear cost-benefit assumptions, MDP models suggest that farms with high pre-existing levels of ecosystem services (e.g. farms with greater surrounding landscape diversification) find it optimal to invest further in diversification practices promoting biodiversity and ecosystem services. The opposite is true for farms with low initial levels of ecosystem services, leading to a bifurcation -- either highly diversified or highly specialized and simplified farms. In contrast, intermediate levels of diversification occur under the assumptions of diminishing returns to, or tradeoffs among, ecosystem services. The model predicts a policy-relevant finding: that increases in diversification and ecosystem services induced by regulatory incentives persist long beyond the incentive period.