贵州省烟田杂草生态位研究

Weeds species niche in tobacco field in Guizhou province

利用样地调查方法,以物种重要值作为资源状态指标,运用改进的Levins生态位宽度指数和Pianka生态位重叠指数对贵州省烟田主要杂草生态位进行分析,从而为预测烟田杂草种群更替提供依据。结果表明:贵州省烟田杂草中,马唐(0.8353)、辣子草(0.7523)、繁缕(0.6333)、狗尾草(0.5941)、尼泊尔蓼(0.5878)、艾蒿(0.5595)、鸭趾草(0.5437)等是贵州省烟田杂草生态位宽度较大的种群;16种贵州省烟田主要杂草之间,生态位重叠值大于0.500的杂草种对共有51对,占总对数的42.50%。认为马唐、辣子草、繁缕、狗尾草、尼泊尔蓼、艾蒿、鸭趾草是贵州省烟田杂草的优势种群,具有较高生态位宽度的烟田杂草与其他杂草的生态位重叠值较大,具有相似形态特征的杂草间生态位重叠值较大。

By the method of sampling plot investigation and using the importance value of species as an indicator of resource status, the research studied the niche breadth and niche overlap of the main weeds species in Guizhou province based on improved Levins niche breadth index and Pianka niche overlap index, in order to forecast the change trend of weeds species in tobacco field. The results showed that, among weeds in Guizhou tobacco field, Digitaria sanguinalis （0.8353）, Galinsoga parviflora（0.7523）, Stellaria media（0.6333）, Setaria viridis （0.5941）, Polygonum nepalense（0.5878）, A rtemisia argyi（0.5595） and Commelina communis （0.5437） had larger niche breadth than other species. Among 16 main weeds, niche overlap values of 51 pair-species were greater than 0.500 with 42.50% of the total. It turned out to be that, D. sanguinalis, G. parviflora, S. media, S. viridis, P. rtepalense, A. argyi and C. communis were dominant weeds species in tobacco field in Guizhou province. The tobacco field weeds with greater niche breadths generally had greater niche overlaps with other weeds and the niche overlaps among weeds that had similar morphological characters were much greater.