大白菜上七星瓢虫空间格局及抽样技术研究

Spatial Pattern of Ladybird Beetle on Chinese Cabbage and Its Sampling Techniques.

一、引言种群的空间格局是生物种群的一项重要特征,常常影响物种的空间分布、结构和活动;影响捕食者对被食者的寻找。从而影响了捕食效率。还影响种群密度、死亡率及生殖力的空间关系,影响抽样调查方法。

The spatial pattern of ladybird beetle Coccinella septempunctata on Chinese cabbage follows a Poisson distribution. In data processing, Iwao's m-m model and its improvements are used. The fitness of Pearson-Ⅲ curve equation to the distribution of ladybird beetle population is tested and optimum sampling size and area for different population densities and relative pracisions are determined. It is concluded that when the population density of ladybird beetle is around 2.044 individuals per m^2 or 0.344 individuals per plant, its distribution is random.