丹东地区稻田杂草种间的生态关系分析

Studies on Ecological Relationships of Weeds in Ricefields in Dandong Area

对丹东地区27个稻田样点杂草的优势度等级进行7级目测,将所得数据转换成重要值,以此计测杂草的生态位宽度和生态位重叠值。以生态位重叠值为指标,用聚类分析中的最小生成树法,直观地表示该地区稻田杂草种间生态学关系。结果表明:长芒稗(Echinochloa caudate)、雨久花(Monochoria korsakowii)、鸭舌草(Monochoria vaginalis)、牛毛毡(Eleocharis yokoscensis)、无芒稗(Echinochloa crusgalli)、浮萍(Lemna minor)、水绵(Spirogyra communis)、扁杆藨草(Scirpus planiculmis)等杂草生态位较宽,是该地区的主要杂草。在27个样点的17种杂草中,长芒稗、牛毛毡、雨久花和鸭舌草等杂草的生态位重叠值较大。与杂草稻(Oryza sativa)较为接近的有无芒稗(Echinochloa crusgalli)、水莎草(Juncellus serotinus)、异型莎草(Cyperus difformis)、芦苇(Phragmites communis)等。

In the rice fields in Dandong area,27 sites under different ecological conditions were surveyed in detail by seven grades to obtain the weeds niche breadth. Based on the cluster analysis of the 27 sites, their intervals of ecological distance were obtained, and the niche overlaps of weeds were then calculated. The ecological relationships of weeds in rice fields in this area were also analyzed by the minimal tree method of cluster analysis .The results showed that Echinochloa caudate, Monochoria korsakowii, Monochoria vaginalis, Eleocharis yokoscensis, Echinochloa crusgalli ,Lemna minor, Spirogyra communis, Scirpus planiculmis had the bigger niche breadth, being the main weeds in rice fields in Dandong. Among the 17 weeds in 27 sites, Echinochloa caudate,Eleocharis yokoscensis,Monochoria korsakowii and Monochoria vaginalis had bigger niche overlaps. While the niche overlaps between Oryza sativa and Echinochloa crusgalli,Juncellus serotinus ,Cyperus difformis, Phragmites communis were higher too.