内蒙古磴口县沙化地区主要草本植物空间分布格局及抽样技术

Spatial Distribution Pattern and Sampling Technique for Main Herbaceous Plants in Desert Land of Inner Mongolia

以内蒙古磴口县境内的主要草本种群为研究对象,用5种聚集度指标调查沙化地区优势种群在不同样地中的空间分布格局。结果表明:芦苇(Phragmites australis)、蓼子朴(Inulasal soloides)和猪毛菜(Salsola collina)种群是以聚集分布为主,聚集分布主要是由外界因素与物种本身特性共同引起的;猪毛菜在部分低密度样地呈现随机分布和均匀分布。Iwao的M*-回归模型和Taylor指数公式进一步测定表明,芦苇、蓼子朴和猪毛菜种群个体间相互排斥,且聚集强度都具有密度依赖性。抽样技术结果证明:密度越大,芦苇和猪毛菜的理论抽样数就越小;蓼子朴则相反。

An experiment was conducted to study the spatial distribution pattern of the main herbaceous plants on different desert plots in Inner Mongolia by means of five aggregation indices. Result shows that the dominant spatial pattern of Phragmites australis, lnula salsoloides and Salsola coUina are aggregated distribution, which is mainly caused by surrounding factors and characteristics of species itself. S. collina exhibits random distribution or even distribution on the plots with low density. Analysis of Iwao M^＊ - x regression and Taylor＇s power law indicates that the individuals in each population of P. australis, I. salsoloides and S. coUina exclude each other, and the aggression intensity depends on plant density. Sampling result indicates that the higher the plant density, the lower the theoretical sampling number of P. australis and S. collina, while I. salsoloides is on the opposite side.