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 and knowledge gaps. Using field-experimental data, crop N uptake responses to fertilizer management were parsimoniously conceptualized and integrated into a catchment diffuse-N model. The improved catchment modeling further facilitated integration with agricultural budget-based assessments. The integrated analysis in a mesoscale catchment disentangled contrasting agri-environment functional mechanisms in typically flashy chemodynamic and transport-limited chemostatic export regimes. Moreover, the former was actively responsive to interannual climatic variability and agricultural practices; the latter exhibited drought-induced enhancement of N enrichment, which could likely be mitigated through reduced fertilization. This interdisciplinary integration of data and methods provided an insightful evidence base for multi-sector targeted measures, especially under cumulative impacts of changing climate and fertilizer-use intensities.
Bibliographical noteFunding Information:
The work is supported by the TERENO and MOSES projects, Helmholtz Association. The authors highly acknowledge the data from the Extended Static Fertilization Experiment at Bad Lauchst?dt and the State Institute for Agriculture and Horticulture Saxony-Anhalt. The authors also thank the German Weather Service, the Federal Institute for Geosciences and Natural Resources and the State Agency for Flood Protection and Water Management Saxony-Anhalt for the model setup data. The authors thank the Editor Harihar Rajaram and two anonymous reviewers for their constructive comments. Open access funding enabled and organized by Projekt DEAL.
Data Availability StatementThe data used are available at https://doi.org/10.48758/ufz.12211. The mHM-Nitrate model code is available at https://doi.org/10.5281/zenodo.3891629.
- climatic variability
- crop N uptake conceptualization
- fertilization experimental data
- fully distributed catchment modeling
- integrated agri-environment functioning
- targeted mitigation measures