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本文根据我们严密设计的小集水区径流场连续6年的水文测定数据,进行了杉木人工林水量平衡和蒸散的研究。结果表明:集水区年平均降雨量1065.5 mm,在林冠作用面降雨量的分配中,林冠截留雨量264.6ram,截留率24.8%;穿透过林冠层的雨量799.82mm,树干径流量1.08mm,分别占降雨量的75.1%和0.1%。林内降水到达林地时,在枯枝落叶层这个作用面上净降水进行再分配,其中,地表径流量9.27mm,地下径流量203.00mm,总径流系数0.199。土壤蓄水量月变化较大,但年变化很小,占降雨量的1.2%。系统水量最大的输出是蒸散,每年以气态形式返回大气的水量868.03mm,占降雨量81.3%。在蒸散的水量中,林冠截留雨量的直接物理蒸发量为264.6mm,占总蒸散量的31.6%。
In this paper, based on the hydrographic data of the closely designed small catchment runoff field for six years, the paper studies the water balance and evapotranspiration of Cunninghamia lanceolata plantations. The results showed that: the average annual rainfall of catchment was 1065.5 mm. In the distribution of rainfall on canopy, the canopy interception rainfall was 264.6 mm and the retention rate was 24.8%. The rainfall of 799.82 mm, the trunk runoff of trunk canopy, Accounting for 75.1% and 0.1% of rainfall respectively. When the precipitation in the forest reaches the forest land, it is redistributed through net precipitation on the role of litter layer. Among them, the surface runoff is 9.27mm, the underground runoff is 203.00mm and the total runoff coefficient is 0.199. Soil water storage monthly changes larger, but the annual change is very small, accounting for 1.2% of rainfall. The maximum output of the system water is evapotranspiration, the amount of water returning to the atmosphere every year in the form of gas is 868.03 mm, accounting for 81.3% of the rainfall. Among evapotranspiration, the direct physical evaporation of canopy interception rainfall was 264.6 mm, accounting for 31.6% of the total evapotranspiration.