基于氢氧同位素技术的滇东南峰林湖盆区不同群落降水分配过程

Precipitation Distribution Processes in the Peak Forest-lake Basin of Southeastern of Yunnan Province Based on Hydrogen and Oxygen Stable Isotope

【目的】选择滇东南文山州普者黑峰林湖盆区为研究区,探讨岩溶地区植被恢复对降水分配过程的影响。【方法】通过对当地大气降水δ^(18)O以及不同群落穿透水δ^(18)O的分析,结合当地大气降水量与林内降水量,应用SPSS软件进行线性回归分析。【结果】(1)当地大气降水线方程为:δD=8.764δ^(18)O+21.558。月降水δ^(18)O和降水量相关性不大,雨量效应不明显。(2)小叶羊蹄甲灌丛穿透水δ^(18)O与降水δ^(18)O相关性大于清香木次生林,较大的群落盖度、强烈的蒸散作用使清香木次生林穿透水δ^(18)O与降水δ^(18)O产生差异。(3)所有群落林内降水量都与林外降水量有高度相关性,其中云南松人工林>小叶羊蹄甲灌丛>清香木次生林。(4)清香木次生林优势种清香木林冠截留率最大,树种组成单一、林龄较小的云南松人工林林冠截留率较小。【结论】森林群落的水文过程对于地区水文循环和调蓄有较大意义,随着群落的正向演替和植被恢复,群落水文调节功能不断增大,对降水δ^(18)O以及降水分配过程影响更大,植被水土保持、水源涵养的功能愈加显著。

【Objective】The objective of this study was to investigate the effect of vegetation restoration onthe precipitation distribution process in the Puzhehei peak forest-lake basin of southeastern of Yunnanof karst area.【Method】The啄18O contentd of precipitation and throughfall in different forests were measuredand linear regression analysis was used in the study by SPSS software.【Results】The results wereshown as follows:淤The line equation of local precipitation was啄D=8.764啄18O+21.558.The correlationbetween啄18O and monthly precipitation was not significant and the rainfall effect was not obvious;于Thecorrelation between throughfall啄18O from Bauhinia hookeriana shrubbery and precipitation啄18O wasgreater than that of Pistacia weinmannifolia secondary forest.This could be due to the fact that P.weinmannifolia secondary forest had larger community coverage and strong evapotranspiration.盂Theprecipitation within the forests was strongly correlated with the precipitation outside the forests,with anorder of P.yunnanensis plantation>B.hookeriana shrubbery>P.weinmannifolia secondary forest.榆P weinmannifolia was the dormant species in the P.weinmannifolia secondary forest,whose canopy interceptionrate was the highest.P.yunnanensis plantation had a low rate of canopy interceptionbecause ofunitary species composion and young age.【Conclusions】The hydrological process of forest communitiesis of great significance to the regional hydrological circulation and transfer function.With the positivesuccession of the community,the hydrological regulation function of the community could increase andthere could be greater impact on precipitation啄18O and precipitation distribution process.Therefore,thefunction of vegetation for soil and water conservation becomes more and more significant.