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为准确掌握圆柏大痣小蜂幼虫在祁连圆柏母树林内的种群发生动态,以祁连山东段寺大隆林场盆沟流域分布的祁连圆柏天然母树林为研究对象,通过在试验地布设样地和随机选取样株进行圆柏大痣小蜂危害调查,采用聚集度指标法和回归分析法对其空间分布格局进行分析。结果表明:(1)圆柏大痣小蜂幼虫在祁连圆柏树冠中部幼虫量显著高于树冠上部和下部(树冠中部的幼虫数占总幼虫数52.15%,P<0.05),幼虫数在树冠在东、南、西、北方位上所占的比例为58.47%、64.66%、30.12%和27.48%;(2)圆柏大痣小蜂幼虫在祁连圆柏母树林内均呈聚集分布,且聚集强度随种群密度的升高而增加,幼虫聚集由害虫本身和环境因素共同作用造成;(3)在回归分析检验中,以La-m模型的拟合效果最优。
In order to accurately understand the population dynamics of the larvae of the pollinator Schizonepeta grandiflorus in Sabina przewalskii population in Qilian Mountains, the natural forests of Sabina przewalskii distributed in the basin ditch grove in the eastern part of Qilian Mountains were studied. And random samples were selected for pollinating the pollinator wasps. The spatial distribution pattern was analyzed by the degree of aggregation index and regression analysis. The results showed as follows: (1) The larvae of the larvae of Sabina przewalskii in the crown of the Sabina przewalskii were significantly higher than those in the upper and lower canopy (52.15% of the total number of larvae in the crown, P <0.05) The proportions of east, south, west and north positions were 58.47%, 64.66%, 30.12% and 27.48%, respectively. (2) The density of larvae increased with the increase of population density. The larvae aggregation was caused by the interaction of pests and environmental factors. (3) La-m model was the best fit in regression analysis.