Concepts

The bidirectional exchange of water between groundwater aquifers and surface water bodies including streams, with groundwater contributing baseflow to streams and streams providing recharge to groundw...

Major form of organic carbon across aquatic ecosystems, fueling stream metabolism and mediating key biogeochemical processes

The degree to which water movement is facilitated or impeded through connected flow paths in subsurface sediments

Mineral formation from ascending hydrothermal solutions

Shallow subsurface zone where river and groundwater mix, serving as a source or sink of reactive nitrogen depending on water residence times and nitrogen transformation rates

Organic carbon derived from sedimentary rocks that is often poorly quantified and influences soil organic carbon composition, age, and stability

Modeling approach that couples transport processes with geochemical reactions to understand subsurface flow and chemical interactions

Geographic classification system used to reduce complexity and simplify presentation of continental-scale results

Chemical composition of water occupying soil pore spaces, indicating mobility of dissolved constituents

Geographic patterns in biodiversity and chemical diversity across latitudinal and environmental gradients

The association of uranium with different solid-phase mineral forms that influences uranium mobility between solid and water phases