Special Variation of Soil Respiration and Its Effecting Factors in Temperate Deserts, China

The variation of soil respiration of desert riverside woods community in a typical section in the lower reaches of the Tarim River was monitored with a LI-8100 soil CO2 efflux system, and synchronously, the variation of some related factors was observed, including vegetation coverage, groundwater table, soil characteristic and temperature..etc. By analyzing the soil respiration's correlation with the above factors, we observed:1) although the soil respiration somewhat responded to the temperature variation, the temperature was no longer its single restricting factor, for the life activity of root system and soil microorganism were very easily influenced and conditioned by some other factors; 2) the groundwater in the monitored area had certain influences on the soil respiration rate, turning out as, the bigger the groundwater table was, the smaller the soil respiration rate became, and it was also true to the contrary direction; 3) at the same time, vegetation coverage and soil characteristic also had influences on soil respiration process;4) a multi-variable model as temperature-soil salt-nutrient- vegetation coverage-the groundwater can account for 72.7% of the special variation of soil respiration in dry regions.