云南牟定三种人工林森林水文生态效应的研究

Hydrological and Ecological Effect of Three Man-made Forests in Muding County of Yunnan Province

利用标准径流小区技术 ,对云南牟定三种人工林进行了森林水文生态的研究。研究表明 ,在森林树种个体水文生态作用方面 ,直干桉和黑荆树冠截留能力比云南松强 ,而云南松树干茎流量较高 ,直干桉树冠下降雨量比云南松、黑荆要大。三种树种水文生态作用的差异与其树种的生物学特征特性有关。在人工林群落调控地表径流方面 ,直干桉 -黑荆混交林和云南松人工林群落与无林地对照、直干桉人工林群落相比 ,具有强调控径流的能力。几种树种树冠下降雨量、树干茎流量、树冠截留量与降雨量有很好的相关性 ,可以用线性回归方程来模拟。人工林群落对径流的调控 ,主要体现在人工林群落使地表径流发生频率降低 ,径流量减小。人工林群落对径流的调控能力是的无林地的四倍 ,但是在高的降雨强度下 ,这种调控能力会明显降低。

The experiment employed the techniques of standardized runoff plot to research fixedly and quantitatively the abilities of the runoff control of three kinds of man made forests and canopy hydrological effects in Muding county of the upper Yangtze River area in 1998 and 1999. The results indicated that the land surface runoff volume was respectively 35.19 m 3/a, 8.42 m 3/a,15.95 m 3/a,10.63 m 3/a in the plots of non forests P.yunnanesis ,E.maedenii and A.mearnsii community. The abilities of the runoff control of the man made forest communities were much greater than non forest contrast, and among three man made communities, mixed Eucalyptus maidenii Acacia mearnsii community and Pinus Yuannanensis community were superior to other communities. Moreover, man made forest communities have lower frequency of runoff at the same rainfall condition. Man made forest communities produced runoff only when the rainfall intensity was up to 0.4~1 cm/h compared to < 0.3 cm/h when non forest contrast just begun to. For the hydrological effects of canopy, the interception rate of A.mearnsii was the highest among three tree species, but there was the high stemflow on the stem of P.yunnanensis . The mathematical models that could predict the canopy entrapment volume, stemflow volume, throughfall of several communities have been given.