Interpreting soil CO2 transport and production in oasis cotton field, central Asia

Abstract

In order to explore soil profile CO2 transport and production, values of vertical soil profile CO2 concentration, moisture and temperature were measured continuously during whole cotton growing season in oasis cotton field of Aksu National Experimental Station of Oasis Farmland Ecosystem, central Asia. Simultaneously, soil CO2 efflux was measured by chamber system to assess the deducing result by Fick’s first law. In our experiment, soil CO2 effluxes were determined by two related intimately methods. Soil CO2 releasing at 0–20 cm depth was calculated by gas transport equation and was found to be closely related to soil CO2 efflux. However, mean values of soil CO2 production at 0–20 cm depth were less than those of soil CO2 efflux during the whole cotton growing season. Moreover, there were some negative values of CO2 production at 0–20 cm depth found during the experimental period.