南京地区油菜田杂草群落特点及分布规律的研究

利用７ 级目测法调查了南京地区油菜田３１ 个样点的杂草优势度级，并以其重要值为指标，对３１ 个样点的杂草群落进行计算机模拟聚类分析。结果表明，受耕作措施、除草剂的施用等因素的影响，南京地区油菜田杂草群落类型多样化。３１ 个样点主要聚为四种类型，其中旱（ 大豆、玉米等） 茬油菜田样点聚为一类，主要以猪殃殃、波斯婆婆纳、野老鹳草等旱生杂草为优势种，稻茬油菜田样点聚为三类，分别以日本看麦娘、牛繁缕、硬草为优势种。旱生杂草猪殃殃、大巢菜等在稻茬油菜田发生量加大。多年使用盖草能、绿麦隆的田块，耐药性杂草野老鹳草、稻搓菜、硬草数量上升。

Weed Communities and Their Distribution in Rape Field in Nanjing Region

random sampling sites under different ecological conditions were surveyed with seven scales by visualization of weed dominance in rape fields in Nanjing. Based on the 17 main weeds, the cluster map of 31 sites was drawed. The results showed that weed communities varied with the changes of soil cultivation and herbicide application. Four weed community groups were divided in 31 sites, one of which was obtained with almost all soybean (com) stubble rape field sites dominated with Galium apalium, and three groups were get with almost all rice stubble rape field dominated with Alopecurus japonicus, Malachium aquaticum, Sclerochloa kengiana, respectively. Dry land weeds such as Galium apalium, Vicia sativa etc had a tendency to increase in rice stubble rape field. Herbicide-toletant weeds, such as Geranium caralinianum, Lapsana apogonoides, Sclerochloa kengiana inclined to increase under the long period use of haloxyfop and chlorotoluron, etc.