金华地区秋旱作物田杂草生态相似关系研究

对浙江金华地区秋旱作物田１７个样点的杂草优势度等级进行了七级目测调查,计测了２２种主要杂草的生态位宽度和生态位重叠值,作出了反映它们间生态学相似程度的最小生成树。结果表明,马唐Ｄｉｇｉｔａｒｉａ ｓａｎｇｕｉｎａｌｉｓ、狗尾草Ｓｔｅａｒｉａ ｖｉｒｉｄｉｓ、千金子Ｌｅｐｔｏｃｈｌｏａ ｃｈｉｎｅｎｓｉｓ、碎花莎草Ｃｙｐｅｒｕｓ ｉｒｉａ、牛筋草Ｅｌｅｕｓｉｎｅ ｉｎｄｉｃａ、石胡荽Ｃｅｎｔｉｐｅｄ

STUDY ON WEED ECOLOGICAL RELATIONSHIPS IN AUTUMN-HARVESTED DRY CROP FIELDS IN JINHUA,ZHEJING PROVINCE

in the autumn--harvested dry crop fields in Jinhua, 17 sites on different ecological conditions were surveyed in detail with seven scales by visualization of weed dominance to crop to obtain the weed important values,the species niche breadthes and nicheoverlaps of 22 species were then worked out on the basis of the data above. The minimalspanning tree revealing weed ecological similarity was drawn based on the niche overlaps. The resluts showed that Digitaria sanguinalis.Setaria viridis.Leptochloa chinensis.Cyperus iria. Eleusine indica. Centipeda minima. Echinochloa crusgalli var. hispidulawere the main weeds in autumn--harvested dry crop fields in Middle Zhejiang. Amongthe 22 weeds, the niche overlaps of ingitaria sangualis. Setaria viridis. Cyperus tri'a.Cyperus rotundus.Eleusine indica were high,while the niche overlaps of lertochloa chinensis' Eclipta prostrata' Mollugo pentaphylla' Lindernia antipoda 1 Luwdigia prostrata'Centl'Peda minima .Mains iap onions were also high, those of Cleome viscosa. Bulbostylisbarbata .Alternanthera philoxeroides with other weeds were small, which indicated thattheir ecological demands were special compared with other weeds' in the autumn--harvested dry crop fields in Jinhua.