广州地区春季叶菜田杂草群落组成及其特征

于春季利用倒置“W”取样法对广州地区不同种植年限及管理水平的叶菜田进行杂草群落调查。结果表明广州地区叶菜田杂草种类共有35种，属12科，25属。其中马齿苋、牛筋草、无芒稗、碎米莎等为主要杂草。种植5年的菜田中以牛筋草+马齿苋+萹蓄等杂草为主；种植10年的菜田中以马齿苋+无芒稗+碎米莎草等杂草为主；长期种植的菜田以马齿苋+碎米莎+凹头苋等杂草为主。种植5年的菜田杂草群落的Shannon-Wiener指数和Pielou指数最大。在高水平管理下的菜田中杂草群落物种丰富度指数最小（4.67）。通过聚类分析表明种植时间和管理水平是影响叶菜田杂草群落结构的主要因素。

Constitution and Characteristic of Weed Community of Leafy Vegetable in Guangzhou Region in Spring

Weed survey was conducted by sampling methods of inverted W-pattern to the leafy vegetable fields with different planting histories and management systems in Guangzhou region in spring.The results showed that 35 species belonging to 12 families and 25 genera were found.Among them,Portulaca oleracea,Eleusine indica,Echinochloa crusgali,Cyperus iria were considered as dominant weeds.Weed community was mainly consisted of Eleusine indica Portulaca oleracea Polygonum aviculare in the fields with five-year planting history,Portulaca oleracea Echinochloa crusgali Cyperus iria in the fields with ten-year planting history and Portulaca oleracea Cyperus iria Amaranthus ascendens in the fields with long planting history.The Shannon-wiener index and Pielou index of weed community in the fields with five-year planting history were the largest and the smallest Riches index appeared in the fields with weed control mainly by artificial(4.67).Clustering analysis showed planting history was the most important factor affecting weed community structure.