中国散居型飞蝗地理种群数量性状变异的分析

本文用模糊聚类分析、系统聚类分析和主成分分析的方法对中国21个散居型飞蝗Locusta migratoria L.Phase Solitaria地理种群的形态测量数据进行了数值分析.这3种分析方法所得的结果是相似的.结果较好地说明了我国21个飞蝗地理种群的地理变异、种群相互关系及亚种的地位.初步确定了我国飞蝗三个亚种的自然地理分界线.陕北的地理种群与陕中、南和华北平原的地理种群非常接近,应认为是东亚飞蝗 L. m. manilensis(Meyen)的一个地理种群.发生基地的散居型飞蝗与一般发生区或扩散区的飞蝗形态特征存在明显差异,作者认为,这是由于发生基地种群密度和生存条件经常处于不稳定状态的结果.主成分分析说明,内蒙古西部的地理种群是介于亚洲飞蝗L. m. migratoria L.和东亚飞蝗L. m. manilensis(Meyen)之间的过渡性种群,但更接近新疆和甘肃的亚洲飞蝗.作者还将E/F、F/C和P/C 3个比值投入运算,这不仅输入了体形的信息,而且也起到给前翅长E、后足股节长F和头宽C加权的作用.作者认为,当在空间和时间上大量连续取样的情况下,飞蝗形态测量学的方法对于确定亚种的地位是比较困难的,这是因为该种固有的多变性和散居型飞蝗在水平和垂直分布上的连续性所造成的.但对于分析地理种群的相互关系方面则显示出优越性.

ANALYSES OF NUMERICAL CHARACTER VARIATIONS OF GEOGRA. PHICAL POPULATIONS OF LOCUST A MIGRATORIA PHASE SOLITARIA IN CHINA

Different morphometric analvses (fuzzy cluster, hierachical cluster and principal component) of 21 geographical populations of Locusta migratoria phase solitaria in China have yielded rather consistent results. The essential geographical variations and the interrelation among the populations are discussed and the geographical delimitation of the three subspecies of Locusta migratoria in China is proposed. It is found that the population of northern Shaan-xi Province, like the populations in other parts of that province and in the North China plain, belongs to the subspecies L. migratoria manilensis. In the North China plain, obvious morphological difference exists among the populations of the outbreak or originating centers and ordinary or temporary breeding areas and this phenomenon presumably is Caused by the enhanced fluctuation of environmental factors which influence population density. The principal component analysis revealed the transitional position of the Inner Mongolian population between the subspecies L. migratoria migratoria of Xinjiang Uighur Autonomous Region and the subspecies L. migrotoria mattilensis of the central and eastern parts of China, but the populations of western Inner Mongolia are more closely related to the subspecies of Xinjing and Gansti. In the analyses, the E/F, F/C and H/C ratios are used not only as important information of body form, but also for weighting the E, F and C values. It seems not appropriate to apply the morphometric method to distinguish the subspecies and to delimit the geographical regions of their distribution by using a great number of samples and extensive collections because of the great inherent variability of the species as influenced its spatial distribution, but it is useful to show the interrelations among the geographical populations.