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As blue water resources become increasingly scarce with more frequent droughts and overuse, irrigated agriculture faces significant challenges to reduce its water footprint while maintaining high levels of crop production. Building soil health has been touted as an important means of enhancing the resilience of agroecosystems to drought, mainly with a focus in rainfed systems reliant on green water through increases in infiltration and soil water storage. Yet, green water often contributes only a small fraction of the total crop water budget in irrigated agricultural regions. To scope the potential for how soil health management could impact water resources in irrigated systems, we review how soil health affects soil water flows, plant–soil–microbe interactions, and plant water capture and productive use. We assess how these effects could interact with irrigation management to help make green and blue water use more sustainable. We show how soil health management could (1) optimize green water availability (e.g., by increasing infiltration and soil water storage), (2) maximize productive water flows (e.g., by reducing evaporation and supporting crop growth), and (3) reduce blue water withdrawals (e.g., by minimizing the impacts of water stress on crop productivity). Quantifying the potential of soil health to improve water resource management will require research that focuses on outcomes for green and blue water provisioning and crop production under different irrigation and crop management strategies. Such information could be used to improve and parameterize finer scale crop, soil, and hydraulic models, which in turn must be linked with larger scale hydrologic models to address critical water-resources management questions at watershed or regional scales. While integrated soil health-water management strategies have considerable potential to conserve water—especially compared to irrigation technologies that enhance field-level water use efficiency but often increase regional water use—transitions to these strategies will depend on more than technical understanding and must include addressing interrelated structural and institutional barriers. By scoping a range of ways enhancing soil health could improve resilience to water limitations and identifying key research directions, we inform research and policy priorities aimed at adapting irrigated agriculture to an increasingly challenging future. 

In the past few decades, farmers and researchers have firmly established that biologically diversified farming systems improve ecosystem services both on and off the farm, producing economic benefits for farmers and ecological benefits for surrounding landscapes. However, adoption of these practices has been slow, requiring a more nuanced examination of both barriers and opportunities to improve adoption rates. While previous research has demonstrated that both individual and structural factors shape farmers' decisions about whether to adopt diversification practices, this study aims to understand the interaction of these individual and structural factors, and how they relate to farm scale. Based on 20 interviews with organic lettuce growers on the Central Coast of California, as well as 8 interviews with technical assistance providers who work with these growers, we constructed a typology to help elucidate the distinct contexts that shape growers' decisions about diversification practices. This typology, which reflects the structural influence of land rent and supply chains, divides growers into three categories: limited resource, mid-scale diversified, or wholesale. In this economic context, limited resource and wholesale growers both experience significant barriers that constrain the adoption of diversification practices, while some mid-scale diversified growers have found a “sweet spot” for managing agroecosystems that can succeed in both economic and ecological terms. The key enabling factors that allow these farmers to choose diversification, however, are not directly related to their farm size, but have more to do with secure land tenure, adequate access to capital and resources, and buyers who share their values and are willing to pay a premium. By focusing on these key enabling factors with targeted policies, we believe it is possible to encourage diversification practices on farms at a variety of scales within California's Central Coast.