Temperature sensitivity of soil respiration and its effecting factors in the different land use

Abstract

Field experiment and laboratory simulated experiment were conducted to estimate temperature sensitivity of soil respiration and its effecting factors in different land use in the Sanjiang Plain. The results showed that exponential equation expressed preferably the rate of change of soil respiration with respect to temperature. The highest Q_(10) value was observed in the Doyeuxia augustifolia wetland, and the lowest Q_(10) value was in the soils cultivated for 15 years. The Q_(10) values in the different land use soils following the order: Doyeuxia augustifolia wetland upland forest soilabandoned cultivated soil soil cultivated for 9 years soil cultivated for 15 years. There were significantly positive correlationship between the Q_(10) values and soil organic carbon, dissolved organic carbon, light fraction carbon, microbial biomass carbon. The Q_(10) values were negatively correlated with heavy fraction carbon. Therefore, the quantity and quality of soil organic carbon was a major factor controlling the Q_(10) values in the different land use. The Q_(10) values were positively correlated with soil water content at 0～10?cm, but not significantly.