Functional Multi‐Scale Integration of Agricultural Nitrogen‐Budgets Into Catchment Water Quality Modeling

Diffuse Nitrogen pollution from agriculture maintains high pressures on groundwater and aquatic ecosystems. Further mitigation requires targeted measures that reconcile agricultural interests in environmental protection. However, the agriculture-related processes of catchment N modeling remain poorly defined due to discipline-specific data knowledge gaps. Using field-experimental data, crop uptake responses fertilizer management were parsimoniously conceptualized integrated into a diffuse-N model. The improved further facilitated integration with budget-based assessments. analysis mesoscale disentangled contrasting agri-environment functional mechanisms typically flashy chemodynamic transport-limited chemostatic export regimes. Moreover, former was actively responsive interannual climatic variability practices; latter exhibited drought-induced enhancement enrichment, which could likely be mitigated through reduced fertilization. This interdisciplinary methods provided an insightful evidence base for multi-sector measures, especially under cumulative impacts changing climate fertilizer-use intensities.