Performing Department
(N/A)
Non Technical Summary
Soil carbon is responsiblefor a sizeable fractionof greenhouse gas emissions mitigation potential in agriculture. Practical ways to buildsoil carbon such as a wide range ofclimate-smartpractices are supportedby government programs and carbon markets. Although the primary major outcome is greenhouse gas emissions mitigation, their widespread adoption is also driven by the resultingsoil healthbenefits, usually referred to as co-benefits. Soilinfluence on plant water relationships is described bysoil properties such as saturation point,field capacity, permanent wilting point, and available water capacity.It is generally accepted that higher soil organic carbonimproves available water capacity, but this observation is of limited use to producers when they intendto visualizethe tangible benefits they can expect. Also, there is little scientific data onwhether increased available water capacity is negligible or sufficiently large for any practical benefits on farm water and climate resiliency. A given increase in available water capacity can result in vastly different outcomes in terms of crop water availability, crop water stress, and irrigation requirements, and these outcomes have not been evaluatedfor U.S. croplands. This project will address this absence of quantitative understanding of producer-facing hydrological impacts of soil carbon sequestration, significantly improving the state of knowledge and effective communication of soil health co-benefits.OBJECTIVES:The overall project goal is to understand, quantify, and communicate the impacts of realistically achievable improvements in soil organic carbonon agricultural water budget and producer-level risk and resiliency across U.S. agricultural ecosystems.The goal will be accomplished bythe following objectives: (1) Quantify change in root-zone available water capacity resulting from realistically achievable soil organic carbon increase across aridity regimes in the United States; (2) Determine site-specific impacts of soil organic carbon increase onsoil water availability, crop water use and stress, and irrigation requirements; and (3) Evaluate spatial and temporal drivers of soil organic carbon-causedcrop and water resiliency.APPROACH:Objectives will be carried out by simulating soil water retention properties and critical agrohydrological components using approaches that are sensitive to soil health indicators. The approach will be make use of publicly available datasets, modeling frameworksand knowledge on relationships among soil characteristics, hydrology, and climate.We will compile estimates of realistically achievable soil organic carbon increase upon adoption of major climate-smart practices, including conservation tillage, cover crops, biochar addition, prescribed grazing, or combination of these practices. We will rely on recent literature synthesis for mean soil organic carbon increase with uncertainty estimates.We will translate baseline and improved soil organic carbon across United States into baseline and improved available water capacityacross the United States using predictive functions of soil properties. Finally, we will determine the sensitivity of plant usablesoil water and crop water stress to realistically achievable soil organic carbon increase using soil water budget simulations.Utimately, the deliverables from the project will lead to improved understanding of the relationships between soil organic carbon, soil hydrology, and crop resiliency across diverseenvironments.Large-scale quantitative evidencewill enhance communication of incentives for adoption of soil health practices by producers.
Animal Health Component
0%
Research Effort Categories
Basic
60%
Applied
20%
Developmental
20%
Goals / Objectives
The overarching goals of the project are to (a) understand whether and how much will improved soil organic carbon affect the amount of transpirable soil water in the crop root zone, the degree to which crops experience water stress, and irrigation water requirement upon adoption of climate-smart practices; and (b) how do these possible benefits change under different soils, crops, regions, and weather conditions. The goals will be achieved using three objectives:Objective #1: Quantify change in crop root zone available water capacityresulting from realistically achievablesoil organic carbon increase across conterminous U.S.Objective #2: Determine site-specific impacts of soil organic carbon-driven AWC increase on soil water availability, crop water use and stress, and irrigation requirements.Objective #3: Evaluate spatio-temporal drivers of soil organic carbon-driven agrohydrological benefits
Project Methods
Efforts: We will conduct simulations for the following successive efforts:Quantify change in crop root zone available water capacity resulting from realistically achievable soil organic carbon increase across conterminous U.S.Determine how site-specific available water capacity increase will alter soil water budgetEvaluate how different soils, crops, and environmental conditions affect potential benefits from improvedsoil organic carbonEvaluation: We will evaluate the success of the project by ensuring key milestones are accomplished, i.e., robustness of quantitative estimates and their uncertaintiesin each of the target variables mentioned above. Also, documentation and interactive presentation of the change will ensure accessibility of findings for audiences.