Soil management considerations for water resiliency in a changing climate

Providing adequate water for crops is a key consideration for agricultural resiliency. Climate change is expected to exert substantial pressure on crop water supplies through increased rainfall variability and increased evaporative demand. The temporal and spatial variability of these climate change impacts, in combination with many feedbacks, at times operating at different scales, makes identifying specific, yet broadly applicable “one-size-fits-all” soil management solutions challenging. Adaptations that work well in one location may represent a poor management choice in another. Considering the local combinations of climate, soils, and crop production systems is fundamental for identifying appropriate strategies. Nonetheless, some broadly applicable soil management pathways for increasing soil water availability can be identified: (i) maximizing rainfall capture, (ii) maximizing soil water storage capacity (intensity × volume), and (iii) suppressing unproductive evaporative water losses, particularly during intervals when leaf area of the primary crop is low. Selecting climate, soil, and production-system-appropriate tillage and surface cover management practices is among the most relevant considerations for improving soil water availability. Maintaining surface cover favors evaporation suppression and increased capture of precipitation. Tillage choices affect internal soil water storage through impacts on soil properties that influence storage intensity and by altering the volume of soil available for root growth, as well as through effects on surface cover. Promoted management practices aimed at improving soil water availability for increased agricultural resiliency must be practically feasible and cost-effective in order to support their broad adoption, and such constraints should be an important consideration in their development.