我国莲藕主产区莲藕田间杂草组成及群落特征

采用倒置“W”形9点取样法，对湖南益阳、湖北蔡甸、江苏吴江、浙江金华、四川都江堰5个地区的莲藕田间杂草进行调查统计，结果表明：莲藕田间杂草共25种（含变种），隶属于19科、24属，其中禾本科、莎草科和雨久花科的杂草种类较多，共占杂草种类的36％；发生优势度较大的杂草为空心莲子草（ Alternanthera philoxe-roides）和浮萍（ Herba spirodelae）。基于物种优势度进行群落相似性聚类分析发现，湖南益阳与湖北蔡甸的莲藕田间杂草群落相似性最高，四川都江堰地区的莲藕田间杂草群落组成与其他4个地区的差异较大。

Species Composition and Characterization of Weed Community in a Lotus Root Field in China

A weed survey was conducted by sampling nine plots according to a “W” pattern in the lotus root production areas of Yiyang,Caidian,Wujiang,Jinhua and Dujiangyan regions.Twenty-five weeds （ including varieties） belonging to 24 genera of 19 families composed the predominant flora-Gramineae,Cyperaceae and Pontederiaceae weeds.The most frequent and dominant species were Alternanthera philoxeroides and Herba spirodelae.Community similarity cluster analy-sis based on species dominance showed that weed communities associated with lotus root fields from Yiyang and Caidian were very similar and that the weed community in Dujiangyan substantially different to those present in the other four regions.