Context is Everything: Interacting Inputs and Landscape Characteristics Control Stream Nitrogen.

ABSTRACT: To understand the environmental and anthropogenic drivers of stream nitrogen (N) concentrations across the conterminous US, we combined summer low-flow data from 4997 streams with watershed information across three survey periods (2000-2014) of the US EPA's National Rivers and Streams Assessment. Watershed N inputs explained 51% of the variation in log-transformed stream total N (TN) concentrations. Both N source and input rates influenced stream NO₃/TN ratios and N concentrations. Streams dominated by oxidized N forms (NO₃/TN ratio > 0.50) were more strongly responsive to the N input rate compared to streams dominated by other N forms. NO₃ proportional contribution increased with N inputs, supporting N saturation-enhanced NO₃ export to aquatic e

SUBMITTER: Jiajia Lin 

PROVIDER: S-EPMC8673309 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature