两种入侵植物对新疆当地物种多样性的影响

目的]调查两种入侵植物黄花刺茄和刺苍耳对新疆当地植物群落物种种类组成及物种多样性的影响.方法]采用样方法选取两种入侵植物黄花刺茄和刺苍耳分布较多的样地,分别作20个有黄花刺茄和刺苍耳入侵的样方,并在与之相距5 m处没有其入侵的区域,作20个对照样方,应用重要值、物种丰富度指数和均匀度指数分析两种入侵植物入侵区域与未入侵区域当地群落的组成及植物多样性的变化.结果]黄花刺茄的试验样方中共有植物6科14种,而对照样方中有7科29种；刺苍耳的对照样方中植物有11科31种,而试验样方中植物仅有9科23种.两种入侵植物验样方中多数土著物种的重要值均比对照样方中的物种重要值低,黄花刺茄样方中只有萹蓄和蒺藜的重要值相差较小；刺苍耳样方中只有狗尾草的重要值高于试验样方.两种入侵植物的试验样方和对照样方相比,物种丰富度和Pielou均匀度指数J均差异显著或极显著.结论]黄花刺茄和刺苍耳的入侵影响了当地植物群落的结构和组成,导致物种数量减少,使物种多样性降低.

Influence of Two Invasive Plants on Local Plant Biodiversity in Xinjiang

【Objective and Method】Square intercept method was used to survey the two invasive plants Solanum rostratum and Xanthium spinosum in desert grassland and oasis in the hope of finding out their effects on the local plant species biodiversity.In a field where the invasive plants were widely distributed,20 plots invaded by these species were placed and between them with a distance of 5 m,20 other plots which were not invaded by these species were selected as the control plots.Importance value,Simpson index and Pielou index were employed to analyze the pattern of local community biodiversity.【Result】There were total of 6 families and 14 species in all the plots that contained S.rostratum,but the control plots had 7 families and 29 species. There were total of 11 families and 31 species in all the plots that contained X.spinosum,while in control plots there were 9 families and 23 species.The importance value in most native plants was lower,only Polygonum aviculare and Tribulus terrestris had slightly lower importance value invaded by S.rostratum.X. spinosum plots had Setaria vividis.Meantime,Simpson index and Pielou index in the two invasive plants were lower than those in the control plot.【Conclusion】It is indicated that the invasion of S.rostratum and X. spinosum had effects on the structure and composition of the native plants community,resulting in reduced species diversity.