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为了研究不同秸秆还田量对紫色土区土壤线虫群落的影响,作者于2011年5月和9月对川中丘陵区的100%(RMW1)、50%(RMW2)、30%(RMW3)和空白对照(CK)4种秸秆还田量的农田土壤线虫进行了调查。结果发现,随着秸秆还田量的下降,土壤线虫的群落结构有一定变化。总体上,群落密度、食真菌类群和捕食–杂食类群的密度呈波动增加;食细菌类群的密度持续增加;植物寄生类群密度、Shannon-Wiener多样性指数(H’)、植物寄生成熟指数(PPI)和瓦斯乐斯卡指数(WI)呈先增加后下降的变化趋势,且多样性指数在秸秆还田量为30–50%之间最高;类群数、自由生活成熟指数(MI)、线虫通路比值(CR)则先下降后增加;所有变化均不显著(P>0.05)。土壤速效钾含量随秸秆还田量的增加显著提高(P<0.05),且与线虫群落多样性指数呈显著负相关(P<0.05)。研究结果表明,在紫色土区秸秆还田主要是通过改变土壤钾含量对土壤线虫群落产生影响,且秸秆还田量在30–50%之间时有利于维持线虫群落多样性。
In order to study the effects of different straw returning on soil nematode community in purple soil area, the authors evaluated the effects of 100% (RMW1), 50% (RMW2), 30% (RMW3) and blank Control (CK) 4 kinds of straw field soil nematode were investigated. The results showed that with the decline of straw returning amount, the community structure of soil nematodes changed. In general, the density of community, fungal group and predation-omnivorous group fluctuated with increasing density; the density of bacterial flora continued to increase; the density of plant parasitism, Shannon-Wiener diversity index (H ’ ) And the gas-luska index (WI) firstly increased and then decreased, and the diversity index was the highest among 30-50% of straw returning; the number of taxa, MI, nematode pathway The ratio (CR) first decreased and then increased; all the changes were not significant (P> 0.05). The content of available K in soil increased significantly with the increase of straw returning (P <0.05), and was negatively correlated with the diversity index of nematode (P <0.05). The results showed that straw returning to purple soil affected the soil nematode community mainly by changing the potassium content of the soil, and it was beneficial to maintain the diversity of the nematode community when the straw returning amount was between 30-50%.