不同稻作年限下土壤微生物学性质和线虫群落特征的变化  

Changes in soil microbial properties and nematode assemblage over time during rice cultivation

作　　者：刘雨迪[1] 陈小云[1] 刘满强[1] 秦江涛[2] 李辉信[1] 胡锋[1] 

机构地区：[1]南京农业大学资源与环境科学学院土壤生态实验室,南京210095 [2]中国科学院南京土壤研究所,南京210008

出　　处：《生物多样性》2013年第3期334-342,共9页Biodiversity Science

基　　金：国家自然科学基金(30900210);中央高校基本科研业务费(KYZ201207);江苏高校优势学科建设工程(PAPD)

摘　　要：红壤地区旱地改水田后随稻作年限的增加土壤性质会发生改变,但缺乏对百年尺度内土壤动物群落特征变化的了解。本研究选取了旱改水后1yr、10yr、20yr、50yr和100yr五个时序的田块,研究了稻作土壤微生物学性质及线虫群落特征的变化。结果表明,随着稻作年限的延长,土壤微生物生物量碳氮、基础呼吸、矿质氮、速效磷、线虫数量及线虫属数均随稻作时间增长而逐渐上升,在50yr均达到显著水平(P<0.05),在50–100yr变化渐缓或有所下降。线虫群落中植食者的比例显著上升(P<0.05),捕食/杂食者的比例有所下降但差异不显著。线虫通道指数也随稻作年限的增加而逐渐增长(P<0.05),表明土壤食物网结构趋向于细菌通道。稻作年限对线虫群落成熟度指数和结构指数的影响并不一致。总之,土壤微生物学性质和线虫群落在旱改水50yr时土壤各项性质均达到较高水平,随稻作年限的继续延长呈现稳定趋势。The properties of red soil may change over time when paddy fields are developed on what was previously dry land. The effect of rice cultivation duration on soil invertebrates is unknown. Five chronosequences of rice cultivation （1, 10, 20, 50 and 100 years） were selected to investigate the temporal changes of soil microbiological properties and nematode assemblages. The results showed that soil microbial properties （microbial biomass C, microbial biomass N, basal respiration）, nutrient availability （mineral N and P）, nematode abundance and richness of nematode genera generally increased with the duration of rice cultivation. Notably, most soil measurements peaked after 50 years of cultivation （P0.05） and decreased slightly after 100 years. As the period of rice cultivation increased, the proportion of nematode herbivores rose significantly （P 0.05）, while that of predators/omnivores slightly declined. Nematode Channel Ratio （NCR） also increased with cultivation duration （P 0.05）, indicating that the bacterial energy channel was more dominant in old rice fields when compared to those cultivated for a shorter period. Other ecological indices of nematode assemblage such as maturity index and structure index, did not reveal consistent trends with an increased period of rice cultivation. In summary, a change in land use from dry land to paddy fields promotes soil microbial properties and nematode assemblages in the first few decades, which then become stable after 50 years of cultivation.

关 键 词：稻田 耕作年限 土壤微生物学性质 线虫群落 

分 类 号：S154[农业科学—土壤学]