The field of biogeochemistry is focused on processes regulating the flow of chemical elements between living organisms and their geochemical environment. Biogeochemistry includes research at the scale from molecule to landscape, and addresses essential questions related to the effects of global environmental challenges like acidification, eutrophication, pollution, land use change, soil degradation, and climate change on ecosystems and to the mitigation of those problems.
The critical zone is Earth's permeable near-surface layer. It is a living, breathing, constantly evolving boundary layer where rock, soil, water, air, and living organisms interact. Within this theme we will focus on the response of biogeochemical cycles on these global environmental challenges, with an emphasis on carbon, nitrogen and phosphorous, because of their central role in these global issues. The type of research questions people within ELD are addressing include: