黑河中游绿洲不同开垦年限农田土壤线虫群落特征  

Characteristics of soil nematode community along an age sequence of sandy desert soil cultivation in a marginal oasis of middle reaches of Heihe River.

作　　者：王雪峰[1] 苏永中[1] 杨荣[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所临泽内陆河流域研究站流域生态一水文重点实验室,兰州730000

出　　处：《应用生态学报》2010年第8期2125-2131,共7页Chinese Journal of Applied Ecology

基　　金：国家重点基础研究发展计划项目(2009CB421302)资助

摘　　要：对不同开垦年限绿洲农田土壤线虫群落结构特征进行研究,探讨以土壤线虫作为指示生物来评价农作年限对绿洲土壤生态系统结构的影响.共捕获线虫27921条,属25科34属.土壤中的线虫总数随农田开垦年限的增长而增加,食细菌线虫和植物寄生线虫数量在不同开垦年限农田中均占优势,对线虫总数起决定作用,构成了绿洲农田土壤线虫群落的主体;对均匀度指数(J)和优势度指数(λ)进行分析表明,0、10年和老绿洲农田(>50年)线虫群落结构单一,生态系统处于不稳定状态;成熟度指数(MI2-5)和总成熟度指数(MMI)随农田开垦时间的延长而降低.随着农作年限的增加,人为耕作活动对农田土壤生态系统的扰动呈增强趋势,系统结构在时间序列上可分为两个阶段,荒漠土壤开垦10年后土壤性状发生显著变化,是土壤生态系统结构稳定性发生变化的关键时期.土壤线虫群落能够指示由于开垦年限不同所引起的绿洲农田土壤生态系统的变化.This paper studied the characteristics of soil nematode community following the conversion of native sandy desert soil to irrigated farmland in a marginal oasis of the middle reaches of Heihe River basin,aimed to approach the bioindicating function of soil nematodes in soil evolution process.A total of 27921 soil nematode individuals were captured,belonging to 25 families and 34 genera.The total number of nematodes increased gradually with increasing age of cultivation.At all sampling sites,bacterivores and plant parasites were the dominant trophic groups,and made up the main parts of nematode community in oasis farmland.Through the analysis of the evenness index（J） and dominance index（λ） of nematode community,the ecosystems were found to be fragile for the farmlands having cultivated for 0,10,and 50 years.The maturity index MI2-5 and MMI decreased with increasing cultivation age,suggesting that the practice of agricultural use enhanced the disturbance on farmland.The soil properties changed significantly after 10 years of cultivation,which was at a significant change stage for the structure stability of soil ecosystems.The characteristics of soil nematode community could be used as the bioindicator of soil evolution following the conversion of native desert soil to irrigated farmland.

关 键 词：绿洲农田 开垦年限 线虫群落 生态指数 

分 类 号：S154.5[农业科学—土壤学]