滇中常绿阔叶林及云南松林水文作用的初步研究

 本文研究了滇中地区山地常绿阔叶林及云南松林的林冠截留量，冠流和茎流量，地表水土流失量，林地枯枝落叶层持水量，土壤含水量以及雨水、冠流、茎流和地表迳流中营养元素(N、P、K、Ca和Mg)的含量，并分析比较了针、阔两类森林调节和涵养水分的作用和降水中林冠养分的淋溶、迁移特点，对了解滇中亚热带山地森林生态系统的功能和生产力的研究，对本区森林资源的保护，林业的合理经营，均有重要意义。

PRELIMINARY STUDY ON HYDROLOGIC EFFECT OF EVERGREEN BROAD-LEAVED FOREST AND PINUS YUNNANENSIS FOREST IN CENTRAL YUNNAN

Throughfall, stemflow and canopy interception, water retaining capacity of the litter, variational soil water content, soil losses and surface runoff of the plot of retained litter and lost litter as well as the input of elements (N, P, K, Ca and Mg) by rainfall and the output of elements by surface soil erosion in evergreen broad-leaved forest and Pinus yunnanensis forest have been studied in Tonghai county during the rain seasons of 1986 and 1987.The results showed that the ability of regulating rain water of two forests was different. In evergreen broad-leaved forest, average annual percentage of canopy interception was 18.2% of the rainfall and was 13.4% in Pinus yunnanensis forest. The average annual percetage of stemflow for two forests was only 0.3–0.5% of the rainfall. The soil water content of evergreen broad-leaved forest was 15–40% higher than that of Pinus yunnanensis forestThe amount of soil erosion in two forests were closely corre lated to the litter loss. After loss of forest litter, the amount of soil losses and surface runoff increased by 11.4 and 1.3 times in evergreen broad-leaved forest and 12.9 and 3.3 times in Pinus yunnanensis forest. The input and output of nutrients in two forests also were different. The amount of NH4-N, P, K, Ca and Mg input by rainfall in evergreen broad-leaved forest was 15.2, 0.5, 50.4, 18.9 and 8.6 kg/ha.a respectively, and the same quantities in Pinus yunnanensis forest were 11.2, 0.6, 40.2, 11.4 and 7.5kg/ha·a respectively. The total amount of the elements output by soil erision in the former forest was 1.6kg/ha·a and that for the latter forest was 0.8 kg/ha.a, and the amount of the elements by soil erosion in two forests increased by 2.4 and 4.2 times respectively after loss of litter layer.