Cycling and retention of nitrogen and phosphorus in wetlands: a theoretical and applied perspective

摘要: SUMMARY. 1 This review considers the internal fluxes and transformations of nitrogen phosphorus in wetland ecosystems. Emphasis is placed on dynamic nature nutrient cycling slanted towards an applied perspective, namely possible use wetlands as sinks for unwanted nutrients. 2 A number basic concepts pertaining to ecosystems are first explained. These are: successional time scales, exchange equilibria storage through flow, resource consumption supply including ideas new regenerated nutrients spiralling concept. Much following material referenced back these concepts. 3 Descriptions pathways different types systems given with emphasis movement into out major compartments systems. 4 The problems conversion qualitative information (or data concentration units) movements transformations, mass flows then discussed. The importance understanding groundwater, evapotranspiration processes effects floods seasonality flow calculations can be significant. Unidentified groundwater sources dilute concentrations, increase concentrations. pattern also alter levels. Increasing residence has effect decreasing outflow. 5 The adding wetlands. concept loading capacity discussed relation length a continue remove from flow. Sediment accumulation degassing seen long-term sinks. Nutrient enrichment results biological changes involve both species composition productivity. Not all deleterious. 6 The literature indicates that natural not particularly effective when compared conventional stripping plants but their value lies removal diffuse runoff at low Dealing this type by means generally feasible. 7 Recent studies show artificially created he (particularly N) only if removed mechanisms understood optimized management techniques.