Homogenization of dissolved organic matter within a river network occurs in the smallest headwaters

摘要: Understanding the drivers of variability in concentration and composition dissolved organic matter (DOM) running waters is a fundamental challenge for aquatic biogeochemistry. Although multiple conceptual frameworks have been proposed to quantify expected changes DOM within river network, few studies collected data document such network. We examine spatial temporal concentration, optical properties, biodegradability network New Hampshire, U.S.A. examined carbon (DOC) properties across 21 locations Lamprey River (548 km2) with weekly monthly sampling 4 years, biodegradable DOC (BDOC) at 7 mainstem 1 year. character were highly heterogeneous scale smallest streams, where land cover nutrient concentrations also greatest. At landscape scale, aromaticity increased wetland decreased developed nitrate concentrations. Despite this heterogeneity we observed similar synchronous seasonal variation regardless position suggesting that broad environmental factors shape sources transport networks. In contrast, BDOC over time or sites was not strongly related quality other predictors. Spatiotemporal patterns provide insight into complex processes influence terrestrial export, in-stream processes, delivery downstream ecosystems.