青海海北地区高山嵩草草甸植物群落的结构特征及其分布格局

COMMUNITIES STRUCTURAL CHARACTERISTIC AND PLANTDISTRIBUTION PATTERN IN ALPINE KOBRESIA MEADOW,HAIBEIREGION OF QINGHAI PROVINCE

对高山草甸主要植物群落结构特征及其分布格局的研究结果表明，矮嵩草草甸植物群落的丰富度最大，隶属１８科，４３属４５种，呈多优势种植物群落；小嵩草草甸居中，隶属１１科，３０属３５种，小嵩草（Ｋｏｂｒｅｓｉａｐｙｇｍａｅａ）为优势种；藏嵩草沼泽化草甸最小，隶属９科，２１属２３种，藏嵩草（Ｋ．ｔｉｂｅｔｉｃａ）为优势种。其中，有９个种群为３个群落中的共有种，分别占矮嵩草草甸、小嵩草草甸和藏嵩草沼泽化草甸总种数的２０．００％、２５．７１％和３９．１３％。它们在水分资源位上的生态位宽度较大。３个植物群落类型的种－面积关系呈对数曲线分布，群落的最小样方面积为０．２５ｍ２或０．５ｍ２较适宜。种－多度分布呈对数正态分布。

In this paper,the structure characteristic and pattern of distribution for main communities of Alpine meadow were studied in range of Haibei,Qinghai.The results are as follows:In K.humilis meadow the richness of plant community was the maximum,45 species belonging to 43 genera and 18 families were recorded.And there were a number of dominant species.In K.pygmaea meadow the richness was medium,35 species belonging to 30 genera and 11 families were recorded,and the dominant species was K.pygmaea. In K.tibetica swamp meadow the richness was minimum,23 species belonging to 21 genera and 9 families were recorded,and the dominant species was K.tibetica.There were 9 common species in the three communities.They were 20.00%,25.71% and 39.13% of total species,respectively,in K.pygmaea meadow,K.humilis meadow and K.tibetica swamp meadow.The niche width of those 9 species for water resource was wider than that of other species.The correlation of speciesarea could be described by logarithm curve.The area of the smallest sample was suitable by 0.25m^2 or 0.5 m^2 in three communities.The pattern of distribution of speciesabundance is predicted by lognormal distribution,there was given by S(r)=SQe-(a2R2)