An Integrated Agriculture, Atmosphere, and Hydrology Modeling System for Ecosystem Assessments

Area of Science:

• Environmental modeling
• Agricultural science
• Atmospheric science
• Hydrology

Background:

• Nutrient cycling significantly impacts air and water quality.
• Existing models often lack integration across land, water, and air processes.
• Accurate simulation of agricultural impacts on the environment is crucial.

Purpose of the Study:

• To develop and evaluate a regional-scale integrated modeling system (IMS).
• To enhance understanding of nutrient (N) cycling and its effects on air and water quality.
• To improve agricultural impact assessments through integrated land-atmosphere-hydrology modeling.

Main Methods:

• Integrated Environmental Policy Integrated Climate (EPIC), Weather Research and Forecast (WRF), Community Multiscale Air Quality (CMAQ), and Soil and Water Assessment Tool (SWAT) models.
• Centralized Fertilizer Emission Scenario Tool for CMAQ (FEST-C) with enhanced SWAT integration (v1.4).
• Simulations conducted over three years using WRF/CMAQ weather and N deposition data.

Main Results:

• Simulated crop yields and N/water budgets align with physical reasoning and survey data.
• Improved ammonia (NH3) flux modeling reduced biases in gas-phase NH3 and wet deposition.
• Hydrology and water quality simulations in the Mississippi River Basin showed realistic streamflow and dissolved N patterns.

Conclusions:

• The developed IMS effectively simulates land-water-air processes for environmental analysis.
• The system demonstrates reasonable performance in predicting N cycling impacts on air and water quality.
• Identified limitations provide a roadmap for future enhancements in integrated multimedia modeling.