The Effect of Thermal Convection on Earth-Atmosphere CO2 Gas Exchange in Aggregated Soil Academic Article uri icon

abstract

  • Gas transport in soils and surface-atmosphere gas exchange are important processes that affect different aspects of soil science such as soil aeration, nutrient bio-availability, sorption kinetics, soil and groundwater pollution and soil remediation. Diffusion and convection are the two main mechanisms that affect gas transport, fate and emissions in the soils and in the upper vadose zone. In this work we studied CO 2 soil-atmosphere gas exchange under both day-time and night-time conditions, focusing on the impact of thermal convection (TCV) during the night. Experiments were performed in a climate-controlled laboratory. One meter long columns were packed with matrix of different grain size (sand, gravel and soil aggregates). Air with 2000 ppm CO 2 was injected into the bottom of the columns and CO 2 concentration within the columns was continuously monitored by an Infra Red Gas …

publication date

  • December 1, 2011