oVERVIEW

Broadly, I study how ecological and biogeochemical processes link scales in aquatic ecosystems, ranging from the genetic and molecular levels to the landscape levels. Current research focuses on greenhouse gas processes and methane dynamics in soils and lentic waters; geologic methane, stored organic matter, and carbon dioxide contributions to lotic waters; links between hydrology, biogeochemistry, and invertebrate communities in the hyporheic zone of non-perennial streams; and aquatic insect dynamics. I use stable isotope geochemistry and mixing models, radiocarbon dating, nutrient analyses, and measures of ecosystem functions (productivity, respiration, biomass, etc.). Visiting scholar at Duke University and Colorado State University. Research scientist at Flathead Lake Biological Station. Twitter: @agdelv

Variation in carbon sources to contemporary food webs

We are using a combination of geochemical and stable isotope techniques to study how contributions of carbon sources ranging from modern to ancient vary across river floodplains.

Carbon dioxide flux from pond waters and sediments

We compared carbon dioxide flux rates from waters and exposed sediments of high elevation ponds with varying hydroperiods and sediment characteristics.

ecology of shallow alluvial aquifers

We are combining physiological, genetic, biogeochemical, and ecological study to understand how complex life persists (read: stoneflies!) in cold, carbon-poor alluvial aquifers.