摘要
根据野外植物调查的分析数据，对流沙河流域干旱河谷不同土地退化程度下植物分布特征进行了研究。结果表明，调查样方中分布的植物共33科57属60种。禾本科（Gramlneae）、菊科（Compositae）、蔷薇科（Rosogetle）、豆科（Legumlnosae）、漆树科（anaeardiaceae）、松科（Pinaceae）、十字花科（cn伽）、桑科（Moraceae）以及马桑科（Corlarlaceae）等9科植物共34种，占所有样方物种数的56．67％，其中早生植物占79．41％，体现了干旱河谷植被的特征。方差分析结果表明，不同土地退化程度之间的物种丰富度差异不显著，但呈现对照（无明显退化）〉重度退化〉中度退化〉轻度退化的趋势；而生物量和盖度均存在极显著差异，其均值均以对照最高，重度退化下最低。人为干扰和海拔通过人为活动强度或气候差异影响不同土地退化程度下的物种丰富度、生物量以及盖度。
According to field investigation data, the vegetation distribution characteristics under different land degradation degrees of dry valley in Liusha Basin were studied in this paper. Firstly, as far as species composition was concerned, sixty species were collected within investigated plots. Thirty-four species belonged to nine families （Gramineae, Compositae, Rosaceae, Leguminosae, Anacardiaceae, Pinaceae, Crnciferae, Moraceae and Coriariaceae） was 56.67 percent of total species and of which dry plants was 79.41 percent. This reflected dry valley＇ s vegetation characteristic. Variance analysis showed that the difference of species richness was not significant among different land degradation degrees, but the mean value of species richness was CK 〉 heavy degradation 〉 medium degradation 〉 light degradation, respectively. Secondly, as far as vegetation quantitative characteristics were concerned, variance analysis indicated that the difference of biomass and cover were both highly significant among different land degradation degrees, the mean value of biomass and cover were both highest under CK and lowest under heavy degradation. Meanwhile the further multiple-range test indicated that biomass under CK was highly significantly higher than the three other land degradation degrees ; cover of CK and light degradation were both highly significantly higher than the cover under medium and heavy degradation , and however the difference between CK and light degradation was not significant. The biomass of CK was 146.88 t/hm^2which was much higher than light degradation （20.35 t/hm^2 ）, medium degradation （6.11 t/hm^2 ） and heavy degradation （ 2.42 t/hm^2 ）, therefore biomass of CK was highly significantly higher compared with the three other degradation degrees. Cover under CK （32.3 % ） and light degradation （83.3 % ） was significantly higher than medium （67.0%） and heavy degradation （37.5%）, never the less, cover under CK and light land degradation degrees was close between communities （about 87.8% ）, thus variance analysis result showed that the difference between CK and light degradation was not significant. At last, the analysis of influencing factors indicated that human disturbance and altitude affected species richness, biomass and cover under different land degradation degrees through the intensity of human activities and climate variance.
出处
《山地学报》
CSCD
北大核心
2006年第B10期38-46,共9页
Mountain Research
基金
四川省教育厅基金（2005A005）,四川省青年科技基金（04ZQ026-018）和ZH14302.
关键词
土地退化
植物分布特征
物种组成
干旱河谷
land degradation
vegetation distribution characteristic
species composition
dry valley
