Desert reservoirs found to trap organic carbon in sediment
… This month, the (University of Colorado Boulder) team published a new study, led by Eckland, in Water Resources Research. The analysis draws on their 2021 field season and parses information about sediment and organic carbon in river water for a surprising result. Reservoirs like Elephant Butte may sequester organic carbon within layers of sediment, especially during periods of drought and flash floods. Essentially, the reservoir acts as a carbon sink, trapping organic material that would otherwise emit carbon dioxide through natural decay. The explanation lies in physics. Normally, when water flows into a reservoir, it spreads out over the surface. But if the river picks up enough sediment, the process flips upside down. Instead of the river water fanning out on top, an underwater current plunges it downward. Scientists call this a “hyperpycnal plume.”