除草剂对农田中小型土壤动物群落结构的影响

采用野外定点试验方法,分析除草剂乙草胺、2,4滴丁酯、噻吩磺隆对农田中小型土壤动物群落结构的影响。结果表明,3次取样共获得中小型土壤动物2 748只,隶属于2门,4纲,10目,其中占优势的类群有甲螨亚目、中气门亚目,分别占总个体数量的51.16%和26.82%,常见类群包括前气门亚目、弹尾目、膜翅目和鞘翅目,占总个体数量的20.27%,稀有类群占总个体数量的1.75%。喷施除草剂使中小型土壤动物个体数量明显减少,尤其是使优势类群个体数量减少最大,使群落多样性指数和均匀度指数增高,优势度指数降低,但没有使土壤动物类群数发生明显变化;3种除草剂影响下的土壤动物个体数量、类群数量、群落特征指数没有很大的差异,在不同层次的表现也没有明显的规律性。

Effects of Herbicides on Soil Meso-and Microfauna Communities in Agroecosystems

A field point experiment was conducted to investigate the effects of applying acetochlor,2,4-D butylate and thifensulfuron-methyl on soil meso-and microfauna communities structure in agroecosystems.The results showed that a total of 2 748 soil small animals were collected in this experiment,belonging to 2 phylums,4 classes,10 orders.The dominant groups were Oribatida and Mesostigmata,accounting for 51.16% and 26.82% of the total number,respectively.Ordinary groups included Prostigmata,Collembola,Hymenoptera and Coleoptera,accounting for 20.27%,and rare groups accounted for 1.75% of the whole individuals.The individual number of soil meso-and microfauna decreased significantly in the samples of applying herbicides,especially the dominant groups.The diversity and evenness index raised while the dominance index dropped due to the influence of herbicides.The effects on group number of meso-and microfauna by herbicides were not obvious.The differences of individual number,group number and community feature index of soil animal were not significant in applying acetochlor,2,4-D butylate and thifensulfuron-methyl.And the same performance in individual and group numbers occurred in different layers.