三江源区人工草地蒸散量与气候因子的相关分析

Correlation Analysis between the Evapotranspiration Quantity and Climatic Factors of Artificial Grassland in Three River Sources Areas

该研究以小型自动气象站观测资料为基础,采用FAO Penman-Monteith方法估算三江源区人工草地参考作物蒸散量,并结合FAO-56推荐的综合作物系数值进行草地实际蒸散量的计算,分析了三江源区人工草地实际蒸散量的变化及其与气象因子的关系。结果表明,草地实际蒸散量的季节变化为单峰曲线,夏季日蒸散量明显大于冬季,在8月中旬达到年度最高值。蒸散与空气温度、太阳辐射和相对湿度均显著相关,但与风速的相关性不显著。各气象因子对人工草地蒸散量影响的大小顺序为:空气温度(T)>太阳辐射(Ra)>空气相对湿度(RH)>风速(u2)。

Based on observation data from the mini-type automatic weather station, the evapowanspiration quantity of reference crops from artificial grassland in three river sources areas was estimated by the method of FAO Penman-Monteith.The actual evapotranspimtion quantity of grassland was calculated according to the synthetic crop coefiqcients referenced by FAQ-56, and the change of the actual evapotranspiration quantity of artificial grassland in three river sources areas as well as the relationship between the evapotranspiration quantity and climatic factors were studied. The results suggested that the seasonal change of actual evapotranspiration quantity in grassland was expressed in a single peak curve with the peak in the middle August,and daily transpiration quantity in summer was significantly larger than that in winter. The evapotranspimtion was significantly correlated with air temperature, solar radiation and relative humidity, but not significantly correlated with wind speed. Effects of climatic factors on the evapotranspiration quantity of artificial grassland were ordered as follow：air temperature （T） 〉 solar radiation （ Ra ） 〉 relative humidity （RH） 〉 wind speed （u2）.