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本文对中国晋盾蚧雌成虫空间分布型及抽样技术进行了研究,研究表明,该虫在旱柳防护林的树冠内和林间均为负二项分布;虫口密度在树冠上的分布,具有东侧>西侧>北侧>南侧和上层>中层>下层之特点;在防护林带或块状林地内,用折线式取样均有较高精度;以着虫末级枝为取样单位,在树冠西侧三层各抽一枝所得虫口密度均值对整株虫口密度均值有很强的代表性。
In this paper, the spatial distribution patterns and sampling techniques of female adults of Ardisia mapa were studied. The results showed that the insects had a negative binomial distribution within the canopy and the canopy of the stands. Side> west side> north side> south side and upper layer> middle layer> lower layer. In the shelterbelts or massive woodland, the sampling with the broken line has higher precision. Taking the last stage of the insect as sampling unit, The average value of population density obtained from each of the three layers on the west side is very representative of the population density of the entire population.