基于PT-Fi模型的新疆地区实际蒸散发计算及其气候环境因子的响应

Actual evapotranspiration estimation of Xinjiang based on PT-Fi model and its responses of climatic and environmental factors

如何准确估计干旱区的实际蒸散发数值是当前研究的热点和难点。为探索新疆区域蒸散发计算的适宜方法,采用MOD-16A2和AET数据集,对Fisher根据Priestley-Taylor和植物生理学理论建立的模型(PT-Fi模型)进行了验证,并通过模型对新疆地区和南北疆区域2001-2010年的实际蒸散发量及其组分进行了计算。结果表明:PT-Fi模型能较好地模拟区域内实际蒸散发量;新疆地区土壤蒸发的年均占比为69.3%,植被蒸腾的年均占比为29.64%,其余为冠层截流蒸发;南疆的蒸散比约为1∶3,北疆的约为1∶2。

How to accurately estimate the actual evapotranspiration in arid areas is a heated and difficult research topic. In order to explore a suitable method for calculating regional evapotranspiration in Xinjiang,the MOD-16A2 and AET data sets were used to verify Fisher’s model (PT-Fi model) based on Priestley-Taylor and plant physiology theory. The actual evapotranspiration and its components of whole Xinjiang,southern and northern Xinjiang during 2001-2010 were calculated using this model. The results showed that the PT-Fi model performed well in the simulation of actual evapotranspiration of the studied areas. The annual average proportion of soil evaporation was 69. 3%,that of vegetation transpiration was 29. 64%,and the rest was canopy interception evaporation. The evapotranspiration ratio of southern Xinjiang was about 1∶ 3,and that of northern Xinjiang was about 1∶ 2.