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应用种群空间分布型聚集度指标对稻槎菜的空间分布型进行了测定。结果表明,泾县稻茬油菜田稻槎菜的空间分布型均符合聚集分布。分布的基本成分是个体群,聚集强度随着杂草密度的增大而增强。这种分布在杂草密度较低时由环境因素造成,在杂草密度较高时由杂草自身特性或与环境的共同作用造成。对其抽样技术进行研究,6种取样方法中Z字形和双对角线式取样误差率较低,以Z字形抽样最佳。同时,利用空间分布的有关参数,在允许误差的范围内给出了不同杂草密度下的理论抽样数。
Spatial distribution patterns of the wild rice (Solanum tuberosum L.) were determined by applying spatial clustering index. The results showed that the spatial distribution patterns of O. japonica in rice stubble field of Jingxian were all in accordance with the aggregation distribution. The distribution of the basic components of individual groups, aggregation intensity increases with weed density. This distribution is caused by environmental factors when weeds density is low and by the weed’s own characteristics or the environment when the weed density is high. The sampling technique was studied. The error rate of zigzag and double diagonal sampling was lower in the six sampling methods, and the zigzag sampling was the best. At the same time, the number of theoretical samples under different weed densities is given within the allowable error by using the relevant parameters of the spatial distribution.