PNNL

Abstract

Dissolved organic matter is one of the most complex mixtures on Earth. Yet, despite its crucial role in global carbon biogeochemistry, our current understanding of DOM processes remains limited. Literature is scarce on riverine DOM dynamics considering both sediment and surface water although they are needed to deepen our understanding of the tight relationship between these environments. By applying the ecological concept of core and satellite species, we developed a data-driven approach for identifying core and satellite species in riverine DOM analyzed via high-resolution ICR39 MS from 97 river corridors. Through our explorative work, we found that comparing the characteristics of rare and frequently encountered DOM pools offers insight into their potential environmental roles in sediment and surface water environments. These analyses may also point to the processes generating variability in DOM composition across large environmental gradients and highlight shared and unique biogeochemical processes that regulate the production, transformation, and consumption of DOM in aquatic ecosystems.