摘要
科尔沁沙地植被的统计学特征及其与沙漠化的关系的分析结果表明:科尔沁沙地不同的植被特征其频率曲线有很大差异。其中,高度、盖度、地上生物量和均匀度均为比较陡峭的单峰曲线,密度为C型曲线,种的丰富度和饱和度为双峰曲线,多样性为抛物线型曲线。其发生频率,固定半固定沙地74 2%的样地植被高度≤18cm、90 9%的盖度≥40%、59 1%的密度>300株·m-2、80 4%的生物量小于210和大于60g·m-2、81 8%的丰富度指数≥10个种、83\^3%的多样性>1.5,56 1%的均匀度≤0.2000,而流动半流动沙地68 8%的植被高度≥18cm、68 8%的盖度≤30%、81 3%的密度<100株·m-2、75 1%的生物量≤90g·m-2,100%的丰富度≤7个种、75%的多样性<1.5000,75%的均匀度指数>0.2000。植被主要特征的变异系数0 37～1 12,并且随着沙漠化的发展植被趋于简单、稀疏、生物量急剧下降,变异性增强。由于科尔沁沙地的主体是固定半固定沙地(80%),其植被的主要特征、频率曲线的主体部分和峰值都是由固定半固定沙地植被决定的。
Statistical properties of the vegetation and its relationship with desertification in Horqin Sandy Land was investigated and analyzed in this paper. The results showed that the frequency curves in the canopy height, plant cover, aboveground biomass and plant evenness all were abrupt single-crest curves, and the curve of plant density appeared a \!C\' form, the species richness and saturation had a double-crest curve, and the diversity had a parabola curve. In fixed and semi-fixed sandy land, the canopy height of 74\^2% samples were \{≤18\} cm, the cover of 90\^9% samples were \{≥40%\}, the plant density of 59\^1% samples were \{>300\} \{n\5m^(-2)\}, the aboveground biomass of 80\^4% samples were from 60 to 210 g·m^(-2), richness index of 81.8% samples were \{≥10\} species, the diversity index of 83\^3% samples were \{>1.5\}, the evenness index of 56\^1% samples were \{≤0.2\}. In shifting and semi-shifting sand lands, the height of 68\^8% samples were \{≥18\} cm, the cover of 68\^8% samples were \{≤30%\}, the density of 81\^3% samples were \{<100\} n·m^(-2 ), the aboveground biomass of 75\^1% samples were \{≤90\} g·m^(-2),the richness of 100% samples were \{≤7\} species, the diversity index of 75% samples were \{<1.5\}, the evenness index of 75% samples were \{>0.2\}. Apparently, the desertification resulted in a significantly changes on the vegetation statistics properties, of which changed extent in the height, density and biomass were greater than those in the cover and richness and diversity.
出处
《中国沙漠》
CSCD
北大核心
2004年第3期274-278,共5页
Journal of Desert Research
基金
国家基础研究规划(973)课题"沙漠化的生物过程及植被恢复重建机理"(TG2000048704)
内蒙古科技厅"十五"攻关课题
关键词
沙地植被
统计学特征
土地退化
沙漠化
sand land vegetation
statistical property
desertification
