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野老鹳草是近年来在稻茬麦田发生日趋普遍的一种阔叶杂草 ,在田间发生频度达33 33%～ 10 0 % ,平均发生密度为 4 6 8～ 15 8 32株 m2 。本研究用 7种聚集度指标 [K、C、L ((1+x)、I、CA、m m、Iδ]测定其空间分布型 ,结果一致表明 ,野老鹳草在田间呈聚集分布 ;运用m -m线性回归和Taylor的幂指数法则分析 ,得到m =3 5 90 3+ 1 1939m、lgv=0 4 5 6 1+ 1 5 0 6 2lgm ,表明野老鹳草在一切密度下均呈聚集分布 ,且具密度依懒性 ,在田间有个体群存在。其聚集原因 ,在低密度下为环境因子造成 ;当密度较大时 ,其本身也可造成聚集。田间调查时 ,以双对角线法取样最好 ,单对角线法、平行法、Z型法也可
Geranium spp. Is a broad-leaved weed that has become more and more common in the field of rice stubble in recent years. The occurrence frequency is 33 33% ~ 100% in the field with an average density of 468 ~ 15 832 m2. In this study, spatial distribution patterns were determined by using seven kinds of clustering index [K, C, L ((1 + x), I, CA, mm, Iδ]. The results showed that the geranium was aggregated and distributed in the field. -m linear regression and the power of Taylor exponent rule analysis, we get m = 3 5 90 3+ 1 1939m, lgv = 0 4 5 6 1 + 1 5 0 6 2lgm, indicating that Geranium spp. was aggregated at all densities, And with density according to laziness, there are individual groups in the field exist.The reason for its aggregation, at low density for environmental factors caused; when the density is large, it can also cause aggregation.Field survey, with double diagonal method Sampling best, single diagonal method, parallel method, Z-type method can be