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应用自记综合气象观测塔，对刺槐和油松林进行了以蒸散研究为目的的防护林热收支特性研究．结果表明：１９９４年生长季日平均实际太阳辐射量为７～２４ＭＪ·ｍ－２；刺槐林林冠对太阳辐射的反射率为１５％，油松林的反射率在１０％以下，反射率的差异是造成两林分净辐射收支相差１～３ＭＪ·ｍ－２的主要原因．春夏两季林分获取的净辐射均由约７０％～８０％的太阳辐射转换而来；秋季的转换率约为６０％，油松林的转换比刺槐约大１％～５％；防护林地区每天获取的净辐射量中，消耗于蒸散的潜热通量部分，在春夏秋三季分别为６５％，８２％和８５％，油松林比刺槐林偏高１％左右；用于气温变化的显热通量部分在春季约占３２％，夏秋为１５％左右，其中刺槐林中显热通量部分在春夏两季所占的百分比相对油松要高出４％～５％；刺槐林地用于土壤热流量部分的热量在５～９月约占净辐射的１％～３％，油松林为２％～５％；１９９４年生长季刺槐林蒸散量为５１９ｍｍ，油松林为５９７ｍｍ．
By using the self-recorded integrated meteorological observation tower, the study on the heat balance characteristics of shelterbelts for Robinia pseudoacacia and Pinus tabulaeformis forest was carried out for evapotranspiration research. The results showed that the average daily solar radiation was 7 ~ 24MJ · m-2 in the growing season in 1994. The reflectance of the canopy forest to the solar radiation was 15% and that of the pine forest was below 10%. The difference of the reflectance was The main reason for the difference between the net radiation revenues and expenditures of the two stands of 1 ~ 3MJ · m-2. The net radiation obtained in the spring and summer was from about 70% to 80% of the solar radiation conversion, the conversion rate in autumn was about 60%, and the conversion of Pinus tabulaeformis to Robinia pseudoacacia about 1% to 5% Among the net amount of radiation acquired per day, the latent heat flux consumed in evapotranspiration was 65%, 82% and 85% respectively in spring, summer and autumn, and about 1% higher in Pinus tabulaeformis forest than in Robinia pseudoacacia forest; The heat flux is about 32% in spring and about 15% in summer and autumn, of which the percentage of sensible heat in Robinia pseudoacacia is 4% ~ 5% higher than that in Pinus tabulaeformis; The heat of the heat flux part accounts for 1% ~ 3% of net radiation and the pine forest is 2% ~ 5% from May to September. The evapotranspiration of Robinia pseudoacacia forest in the growing season in 1994 is 519mm and the Pinus tabulaeformis forest is 597mm.