The role of climate on inter-annual variation in stream nitrate fluxes and concentrations.

摘要: Abstract In recent decades, temporal variations in nitrate fluxes and concentrations temperate rivers have resulted from the interaction of anthropogenic climatic factors. The effect drivers remains unclear, while relative importance seems to be highly site dependent. This paper focuses on 2–6 year called meso-scale variations, analyses these a study characterized by high N inputs intensive animal farming systems shallow aquifers with impervious bedrock climate. Three approaches are developed: 1) an analysis long-term records 30 coastal Western France, which were well-marked cycles concentration slight hysteresis; 2) test control using lumped two-box model, demonstrates that hydrological assumptions sufficient explain cycles; 3) model two contrasted catchments subjected mitigation measures, relation stored groundwater. rivers, (i.e., effective rainfall), particularly dynamics water table rather stable concentration, cyclic patterns. headwater catchment, agricultural can interact according their settings. requirements better distinguish climate human changes integrated management addressed: monitoring, coupling modelling large sets incorporating different sizes, land uses environmental