金华地区早稻田杂草种间生态关系及其图形表示

Studies on ecological relationships of weeds in early rice fields and their graphical expression in Jinhua area of Zhejiang Province

对金华地区２９个早稻田样点的杂草优势度等级进行了七级目测，将所得数据转换成重要值，以此计测了主要杂草的生态位宽度；以早稻－杂草群落梯度代替生态因子梯度，用生态因子间隔作为生态位重叠值计算的加权因子，对该地区早稻田中的杂草生态位重叠值进行了计算；以生态位重叠值为指标，用极点排序和聚类分析中的最小生成树法，直观地表示了该地区早稻田主要杂草的种间生态学相似关系。

In the early rice fields in Jinhua area,29 sites under different ecological conditions were surveyed in detail by seven grades to obtain the weed niche breadth.Based on the cluster analysis of the 29 sites,their intervals of ecological distance were obtained,and the niche overlaps of weeds were then calculated.The ecological relationships of weeds in early rice fields in this area were also analyzed by the minimal tree method of cluster analysis and polar ordination.