Landscape spatial configuration influences phosphorus but not nitrate concentrations in agricultural headwater catchments

Landscape organized (or structured) heterogeneity influences hydrological and biogeochemical patterns across space time. We developed landscape indices that describe the spatial configuration of nutrient sources sinks as a function their distance to stream (lateral dimension) or outlet (longitudinal intersection with flow-accumulation areas. Using monthly nitrate, total phosphorus (TP), soluble reactive (SRP) daily discharge (Q) data from 221 rural catchments (1–300 km2) 2010–2020, we observed higher variability in flow-weighted mean concentrations smaller than larger ones. The configurations also decreased increasing catchment size. A index, calculated arable land use weighted by on flow accumulation, improved prediction TP SRP, but not compared unweighted use. conclude transfer more nitrate transfer, zones riparian areas are critical source for respectively. By contrast, lateral (upslope–downslope) longitudinal (upstream–downstream) dimensions did have an identifiable influence nutrients temporal dynamics. this study can help design landscapes minimize diffuse losses streams show management is first order control losses.