麦田宝盖草的空间分布型及抽样技术研究

研究表明，麦田宝盖草在各种密度下都呈聚集分布，且聚集强度随密度升高而增强，其分布的基本成分是个体群，个体之间相互吸引。当平均密度ｘ＞ ４．１８２２株时，其聚集的主要原因是自身种子集中散落所致；ｘ＜ ４．１８２２株时，聚集原因主要是种子夹杂草籽或施用末腐熟的有机肥等外部环境因素造成的。田间调查以棋盘式和平行跳跃法取样为宜，同时提出了不同密度下的理论抽样数。

Studies on Spacial Distribution Pattern and Sampling Techniques of Henbits in Winter Wheat Field

The study showed that the distribution pattern of henbits in winter wheat field was contagious in the different den sities.The contagious intensity was enhanced with the increase of the density of the weed.The basic element of the distribution was colony and the individual plant drew each other.And at the average density >4.182 2,the main reason for the contagious distribution pattern was due to the aggregated falling of the weed seeds; at the arerage density <4.182 2,the main reason was due to the mixture of wheat seeds and weed seeds and fertilizing poor fermentation compost.The types of parallel and chessboard sampling were suitable for the field investigation of the weed.The theoretical sampling number at different weed density was put forward.