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出 处:《草地学报》1997年第2期108-112,共5页Acta Agrestia Sinica
基 金:农业部"八五"攻关课题
摘 要:本文作者用平均密度(M)、聚集度指标(M*/M)、有虫样方出现频率(F),对狭翅雏蝗在草原的种群动态进行了模糊聚类分析。结果表明,狭翅雏蝗发生的动态规律可分为四个状态集。其中发生在前期末既是预测预报的关键时期,也是药剂防治的有利时机。Fuzzy cluster analysis was carried out. with the data of mean densities, indices of patchiness and rates of occupied plot in different periods of Chorthippus dubius (Zubovsky)which damaged rate of occupied plot dominantly on Ganjia high mountain grassland in Xiahe County, Gansu province. The periods of its population dynamics was studied. The results showed that the population dynamics of this grasshopper could be divided into four distinct periods, in which the second one, the young nymph stage, was the key time for population prediction and chemical control.
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