A Comparison Between Global Nutrient Retention Models for Freshwater Systems

Against the backdrop of increasing agricultural production, population, and freshwater/coastal eutrophication, studies are aiming to understand behavior nitrogen (N) phosphorus (P) in global freshwater system. Global nutrient models typically used quantify amount content systems across different river orders catchments. Such use empirically derived retention equations for predicting fate, these may be using data from a specific region or environment context. Here we IMAGE-GNM, spatially explicit model at half-degree resolution, examine performance several well-known empirical by comparing respective outcomes with observed on scale. The results show that (1) globally, work better N fate than P fate; (2) hydraulic drivers most important factor affecting residual total concentrations, compared functional forms coefficients equations. This study can aid assessing variability accuracy various regional scales, thus further strengthen our understanding eutrophication.