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作 者 ：王尚义,李素清,曹志敏,赵海晓

期 刊 ：生态学报 2007年 27卷 12期 页码：5098~5109

关键词：皇姑梁小流域；人工植被；生态关系分析；TWINSPAN分类；DCA排序；物种多样性；

Keywords:Huangguliang small watershed, artificial vegetation, analysis of ecological relationships, TWINSPAN classification, DCA ordination, species diversity,

摘 要 ：应用双向指示种分析法(TWINSPAN)和除趋势对应分析(DCA)等数量分析方法，对山西岚县皇姑梁小流域人工植物群落生态关系进行研究，将该人工植被划分为12个群丛，分别位于不同的海拔高度和坡向。分类结果很好地反映了人工植物群落类型及优势种的分布与环境因子的关系，并在DCA二维排序图上得到了较好的验证。DCA排序轴反映了群落土壤含水量、坡向、海拔高度、人工植被恢复时间和物种多样性的梯度变化，表明土壤含水量、坡向、海拔高度、物种类型及其配置模式是影响人工植物群落分布和变化的主要环境因子，不同物种配置模式对群落演替和物种多样性变化有重要影响，油松+华北落叶松-沙棘、小叶杨+油松、油松-沙棘、油松-柠条锦鸡儿等组成的乔灌混交林的物种多样性高于柠条锦鸡儿灌木纯林，并且油松+华北落叶松-沙棘混交林的物种多样性高于小叶杨+油松混交林，混交林的生态恢复效果优于纯林，并且对该小流域的生态恢复作用明显。华北落叶松适合在该小流域海拔较高的梁坡顶、半阳坡、半阴坡和阴坡生长，小叶杨适合在其海拔较低的沟底、半阳坡和半阴坡生长，而油松、沙棘、柠条锦鸡儿的生态适应性强，可在其不同海拔和坡向生长。人工植物群落的演替进程，遵循地带性植物群落演替规律。随着群落演替，野生植物不断侵入，油松、华北落叶松、小叶杨等人工林郁闭度增加，沙棘、柠条锦鸡儿等逐渐退化，油松、华北落叶松、小叶杨等出现枯枝、死株现象，这是自然稀疏的结果，亟待加强管理。

Abstract:Ecological degradation is a critical problem faced by every country in the world. The study of restoration of degraded ecosystem has been recently considered as one of scientific issues and public focuses because drastic ecological degradation results in huge economic and ecological loss. Huangguliang small watershed of Lanxian County, located in the northwest of Shanxi province, is one of the most typical ecological frangible areas on the Loess Plateau in North China. Based on the field investigation, two-way indicator species analysis (TWINSPAN) and detrended correspondence analysis (DCA) were applied to the analysis of ecological relationships among artificial vegetation communities in Huangguliang small watershed. It was showed that: (1) One hundred-two samples located in different altitudes and aspects were classified into twelve associations by TWINSPAN and their characteristics, including distribution of dominant species and relationshaip with environmental factors, were described respectively. All results were confirmed by the two-dimensional ordination diagram of DCA. (2) The environmental variables, such as soil moisture, altitude, aspect and succession time were the major environmental factors in affecting the change and distribution of the communities. The results of DCA ordination showed that the artificial associations have their difference distribution along environmental gradient. The first two axes of DCA reflect the gradient of soil moisture, altitude, aspect and succession time of the communities. (3) The distribution patterns of dominant species were highly similar to that of the communities. With the decrease of the altitude, the association of Pinus tabulaeformis, Hippophae rhamnoides and Carex lanceolata were gradually taking place by the association of Caragana korshinskii, Carex lanceolata and Artemisia capillaris, which showed that community distribution patterns were coordinating to the zonal vegetation distribution patterns due to the decrease of elevation and soil moisture. (4) The difference of species diversity of community has main closely correlation to soil moisture, altitude, aspect and succession time, meanwhile, also has closely correlation to the habitat. Species diversity of the artificial vegetation in semi-sunny slope, semi-shadow slope, shadow slope and higher altitude area with better water supply, was much richer than that in sunny slope and lower altitude area. Meanwhile, species diversity plays an important role in the development and distribution of the artificial vegetation communities. (5) Species types and their plant pattern have an obvious interruption effect to the succession of artificial vegetation communities in Huangguliang small watershed. The restoration effects of mixed forest, such as Populus simonii+Pinus tabulaeformis, Pinus tabulaeformis+Larix principis-rupprechtii-Hippophae rhamnoides, Pinus tabulaeformis-Caragana korshinskii, Pinus tabulaeformis-Hippophae rhamnoides, etc. are much better than that of Caragana korshinskii pure forest. And human interruption could accelerate the process of succession, which has validated the previous researchers′ opinions. Moreover, Larix principis-rupprechtii is fit for growing in semi-sunny, semi-shadow slope, shadow slope at higher altitude. Populus simonii is fit for growing in valley and semi-sunny and semi-shadow slope at lower altitude, while Pinus tabulaeformis, Hippophae rhamnoides and Caragana korshinskii with strong ecological adaptability are fit for growing in any of altitude and aspect in Huangguliang small watershed. (6) The course of artificial vegetation community succession in Huangguliang small watershed follows the succession law of local zonal vegetation. With the community succession, the wild plants have continuously invaded and the canopy densities of Pinus tabulaeformis, Larix principis-rupprechtii and Populus simonii etc. forests have increased. While the shrubs of Hippophae rhamnoides and Caragana korshinskii have gradually degenerated. The forests of Pinus tabulaeformis, Larix principis-rupprechtii and Populus simonii etc. have occurred deadwoods, which are the results of self-thinning. So the effective forest management is urgently needed.

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