SOME ADVANCE IN THE MAIN FACTORS CONTROLLING SOIL RESPIRATION

Soil respiration is influenced by many factors, which are different in a variety of spatio-temporal ecosystems. The objective of this paper is to review the main factors including abiotic factors such as the soil temperature, soil moisture, rainfall, soil C/N,biotic factors such as vegetation types, biomass, leaf area index, litter, and human activities as well. Based on the summarization, the Q10 of soil respiration, key controlling factors and interaction among different factors were discussed. Soil temperature, soil moisture are the key factors controlling soil respiration. So it is helpful to estimate the amount of soil respiration on the basis of modeling by these factors. However, the prediction has a limitation of underestimation and overestimation at low and high temperature or moisture conditions respectively. In order to acquire accurate estimation of soil respiration, main suggestions for further study are to: combine measurement of soil respiration by chamber with carbon flux of ecosystem by eddy covariance, measure synchronously the biotic and abiotic factors, especially pay more attention to the role of modification of biotic factors on the performance of abiotic controllers, make more measurement in typical plant phenology phase and different weather conditions, and strengthen experimental manipulation and modeling. In conclusion, soil respiration is a complex biochemical process, which is controlled by certain models although regulated by interactions among multi-factors. In order to get accurate modeling and prediction, key factors need to be sought and estimate synthetic influence of interactive factors.