Methane and Carbon Dioxide Emissions From Reservoirs: Controls and Upscaling.

Estimating carbon dioxide (CO) and methane (CH) emission rates from reservoirs is important for regional and national greenhouse gas inventories. A lack of methodologically consistent data sets for many parts of the world, including agriculturally intensive areas of the United States, poses a major challenge to the development of models for predicting emission rates. In this study, we used a systematic approach to measure CO and CH diffusive and ebullitive emission rates from 32 reservoirs distributed across an agricultural to forested land use gradient in the United States.

Effects of an Experimental Water-level Drawdown on Methane Emissions from a Eutrophic Reservoir.

Reservoirs are a globally significant source of methane (CH) to the atmosphere. However, emission rate estimates may be biased low due to inadequate monitoring during brief periods of elevated emission rates (that is, hot moments). Here we investigate CH bubbling (that is, ebullition) during periods of falling water levels in a eutrophic reservoir in the Midwestern USA.

Urban Stream Burial Increases Watershed-Scale Nitrate Export.

Nitrogen (N) uptake in streams is an important ecosystem service that reduces nutrient loading to downstream ecosystems. Here we synthesize studies that investigated the effects of urban stream burial on N-uptake in two metropolitan areas and use simulation modeling to scale our measurements to the broader watershed scale. We report that nitrate travels on average 18 times farther downstream in buried than in open streams before being removed from the water column, indicating that burial substantially reduces N uptake in streams.