Precision Zonal Management Systems for Resilient Cereal Yields and Ecosystem Services Under Variable Climates.

Increasing climatic variability is likely to increase production risks in cereal agroecosystems and to exacerbate carbon and nitrogen losses from these systems. Reduced tillage and continuous living cover (e.g., cover crops) may help manage these effects, but both impose other costs and risks. Considerable evidence suggests that precision zonal field management (PZM) can reduce such trade-offs. PZM creates functionally-distinct zones on decimeter scales; zones that may differ in decomposition and mineralization rates, potentially isolating problematic aspects of soil building from production, in space and time. Therefore, PZM systems (e.g., ridge tillage) may offer a new frontier for redesign of intensive cereal production in variable climates. To evaluate this potential, we are systemically analyzing and evaluating contributions of PZM to climate change mitigation and adaptation in cereal agroecosystems. Specifically, we are examining the following questions about soil structure, biogeochemistry, and plant-soil interactions:

1. Across a range of soils and climates (IL, MN, MI, PA), do PZM systems improve structural, functional, and biogeochemical attributes of soils (e.g., aeration, water retention, N cycling) that improve climate change mitigation and adaptation?
2. Can PZM promote plant-soil interactions and microbial communities that build soil, reduce production risks and mitigate trace gas emissions?
3. Can PZM provide climate-change mitigation and adaptation over a range of future climate scenarios?

Our project will integrate empirical results in a decision support tool that will help explore climate change mitigation and adaptation potential of intensive cereal production systems. Additionally, we are integrating a range of tools and approaches to manage a multi-regional long-term cropping systems ecology experiment; such experiments pose large coordination, quality-control and data-management challenges. To date, we have initiated a multi-region experiment comparing PZM and non-zonal corn-soybean production systems. Additionally, we have examined long-established PZM systems and find evidence that microbial communities diverge between zones, consistent with functional differentiation between zones.