title: An evaluation of abiotic carbon sinks in deserts.
abstract: Recent field studies have reported anomalous CO2uptake using eddy-covariance techniques in arid and semiarid ecosystems. The rates of CO2uptake are incompatible with changes in situ of organic carbon pools. Here, I examine several potential mechanisms of abiotic CO2uptake in arid and semiarid soils: atmospheric pressure pumping, carbonate dissolution, and percolation of soil water through the vadose zone. Each mechanism is deemed inadequate to explain the observations of the eddy-covariance systems, which must now be questioned for their accuracy in desert ecosystems.
authors.affiliation: Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA.|Cary Institute of Ecosystem Studies, Box AB, Millbrook, NY, 12545, USA.
authors.forename: William H
authors.initials: WH
authors.lastname: Schlesinger
mesh_terms: D002244:Carbon; D057965:Carbon Sequestration; D003889:Desert Climate; D017753:Ecosystem; D012987:Soil; D012988:Soil Microbiology
chemical_list: D012987:Soil; D002244:Carbon
keywords: carbon sequestration; deserts; groundwater; missing sink; soil carbon