Advance in Experimental Research About the Impact on Variation of Soil Water Content to Net Ecosystem CO_2 Exchange in the Cropland Ecosystem

HE Meng;QIN Tian-ling;YU Zhi-lei;WAN Sheng;State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research(IWHR);

variation of soil water content;;net ecosystem CO2 exchange;;cropland ecosystem,irrigation system of water-saving and emission-reducing

The impact of variation of soil water content on net ecosystem CO2 exchange is the hotspot of theoretical researches in irrigation system of water-saving and emission-reducing,which is the key of agricultural management measures to tackle climate changes.Up to now,the domestic and home achievements of relevant experimental research on the influence of variation of soil water content on net ecosystem CO2 exchange were mainly introduced from three scales:indoor,field and large area.Most of the experimental research focused on the effects of variation of soil water content on soil respiration,few studies extend this analysis to impact on net ecosystem CO2 exchange in cropland ecosystem.The researches about the integrity of crop respiration responses to the variation of soil water content,the water stress limit setting under the experimental conditions in indoor and field scales,and the impact on variation of soil water to net ecosystem CO2 exchange in different irrigation methods and different growth periods will be the emphasis in the future.