太白山几类植物群落灌木及草本层的最小取样面积研究

采用2条非饱和与2条饱和曲线方程对太白山7种类型植物群落(Ⅰ.锐齿栎林、Ⅱ.铁橡树林、Ⅲ.红桦林、Ⅳ.巴山冷杉-牛皮桦林、Ⅴ.巴山冷杉林、Ⅵ.太白红杉林和Ⅶ.头花杜鹃-大毛状薹草灌草丛)灌木及草本层拟合的种-面积曲线,计算研究精度要求分别为60%、70%、80%、90%时各群落各层的最小取样面积,并进行分析比较.结果表明,不同群落灌木及草本层最小取样面积均随研究精度增高而增大,群落Ⅰ~Ⅶ灌木层的取样面积分别为96、35、73、63、75、1701、8 m2时,草本层为91、91、57、59、71、657、m2时,可满足精度80%以下的研究要求;灌木层的取样面积为163、62、122、104、120、296、35 m2时,草本层为150、151、109、110、126、1192、9 m2时,可满足精度90%的研究要求.方差分析表明,不同群落灌木及草本层最小取样面积存在差异,有些差异达显著水平(P<0.05).因此,在野外调查时应根据研究精度要求和群落类型合理设置最小取样面积.

Minimum Sampling Areas for Shrub and Herb Layers of Several Types of Plant Communities in Taibai Mountain

The minimum sampling areas for shrub and herb layers of 7 types of plant communities(Ⅰ.Quercus aliena var.acuteserrata community,Ⅱ.Quercus spinosa community,Ⅲ.Betula albosinensis community,Ⅳ.Abies fargesii-Betula utilis community,Ⅴ.Abies fargesii community,Ⅵ.Larix chinensis community,Ⅶ.Rhododendron capitatum-Carex capilliformis var.major shrub-herb community) in Taibai Mountain were determined at the study accuracy level 60%,70%,80% and 90% by fitting species-area relationships using 2 non-saturation and 2 saturation curve equations,and the results were analyzed and compared.The results showed that the minimum sampling areas of shrub,herb layers of different communities all increased with the increase of the study accuracy level,it could meet below 80% study accuracy level when the sampling areas for shrub and herb layers of communities Ⅰ~Ⅶ were set to be 96,35,73,63,75,170,18 m2;91,91,57,59,71,65,7 m2,respectively;and could meet 90% study accuracy level when they were set to be 163,62,122,104,120,296,35 m2;150,151,109,110,126,119,29 m2,respectively.Analysis of variance indicated that there were differences for the minimum sampling areas of shrub,herb layers among different communities,and some of them were significant(P<0.05).Therefore,it should be based on study accuracy level and community types to reasonably set minimum sampling areas in the field survey.