长期施用不同肥料土PLFA指纹特征  

PLFA Fingerprint Characteristics of An Anthropogenic Loess Soil Under Long-Term Different Fertilizations

作　　者：郭芸[1] 孙本华[1] 王颖[1] 魏静[1] 高明霞[2] 张树兰[1] 杨学云[1] 

机构地区：[1]西北农林科技大学资源环境学院/农业部西北植物营养与农业环境重点实验室,陕西杨凌712100 [2]西北农林科技大学水利与建筑工程学院,陕西杨凌712100

出　　处：《中国农业科学》2017年第1期94-103,共10页Scientia Agricultura Sinica

基　　金：国家公益性行业(农业)科研专项(201203030);陕西省自然科学基础研究计划项目(2015JM4130);中央高校基本科研创新项目(QN2012038);高等学校学科创新引智计划(B12007)

摘　　要：【目的】土壤微生物群落结构的组成与活性的变化是衡量土壤肥力的重要指标,研究长期不同施肥和土壤管理方式对塿土微生物群落结构的影响,对于指导塿土施肥和土壤管理,实现农田可持续利用具有重要意义。【方法】以陕西杨凌"国家黄土肥力与肥料效益监测基地"长期肥料定位试验为基础,运用磷脂脂肪酸标记法(PLFA),研究了塿土长期不同施肥及土地利用方式下土壤微生物群落结构及其与土壤理化性质的关系。处理包括:长期不施肥(CK)、单施氮肥(N)、长期配合施用氮钾(NK)、磷钾(PK)、氮磷(NP)、有机肥和氮磷钾(MNPK)以及长期休闲(FL)和撂荒(AB)。【结果】与对照相比,MNPK、NP和撂荒处理土壤总PLFA分别增加218.8%、73.9%和74.3%,细菌分别增加188.3%、80.8%和82.6%,真菌分别增加了315.8%、111.5%和167.0%,放线菌分别增加了23.7%、21.3%和16.3%,同时也显著增加了真菌/细菌比;N、NK和PK土壤总PLFA、细菌、真菌差异不显著,但PK显著降低放线菌的含量;与农田施肥相比,休闲和撂荒显著降低G^+和G^-含量。多样性指数结果表明,长期有机无机配施明显提高土壤微生物群落的Shannon-Winner多样性指数、Simpson优势度和Pielou均匀度指数,撂荒和NP也能显著增加Shannon-Winner多样性指数和Pielou均匀度指数,而长期休闲处理均明显降低了这些指数。主成分分析表明,MNPK、NP、撂荒和休闲土壤微生物群落结构发生较大变化;MNPK显著提高G^-(18:1ω5c,cy19:0ω7c)、细菌(16:0、10Me22:0饱和脂肪酸)及真核生物(18:3ω6c、16:3ω6c,22:2ω6c)的多度值,撂荒(AB)和NP显著提高细菌(15:0,18:0,22:0,17:0饱和脂肪酸)的多度值。RDA分析表明,土壤理化性质对微生物菌群影响的重要性依次为有机质>全氮>含水量>速效磷>pH>容重>速效钾,这些理化因子均是微生物生长的关键因子。【结论】长期有机无机肥配施、氮磷配施和撂荒提高了土壤微生�[ Objective ] The changes of soil microbial community structure and activity are the key indicators for evaluating soil fertility. It is important to study the effects of long-term different fertilizations and soil managements on soil microbial community structure for fertilization and soil management, and even on the sustainable utilization of farmland of the anthropogenic loess soil. [Method] This research was based on the long-term trial of ＂National Monitoring Base of Soil Fertility and Fertilizer Efficiency on Loess Soil＂ in Yangling, Shaanxi province. Soil samples were collected from treatments as farmland without fertilization （CK）, farmland with N fertilizer （N）, N and K fertilizer （NK）, P and K fertilizer （PK）, N and P fertilizer （NP）, and NPK plus cattle manure （MNPK）, fallow land （FL） and abandoned land （AB）. The effects of long-term fertilization and soil management on soil microbial community structure and its relationship with basic soil physio-chemical properties were studied by PLFA and routine analysis. [Result] Compared to CK, total PLFAs, bacteria, fungi, and actinomycetes PLFAs of MNPK, NP and AB were increased by 218.8%, 73.9% and 74.3%, 188.3%, 80.8% and 82.6%, 315.8%, 111.5% and 167.0%, 23.7%, 21.3% and 16.3%, respectively, and also the fungi/bacteria ratio （F/B） was significantly increased. Total PLFAs, bacteria, fungi of N, NK and PK were not significantly different, but PK reduced actinomycetes PLFAs significantly. Compared to farmland soil, FL and AB inhibited the growth of G＋ and G significantly. Shannon-Winner richness index （H）, Simpson dominance index （S）, Pielou evenness index （J） and richness index （S） were all the highest in MNPK, and the lowest in FL. AB and NP could also increase Shannon-Winner richness index （H） and Pielou evenness index （J） significantly. The result of principal component analysis showed that MNPK, AB, NP and FL could significantly change soil microbial community structure. MNPK could increase

关 键 词：塿土 长期施肥 土壤管理 微生物群落结构 磷脂脂肪酸 

分 类 号：S158[农业科学—土壤学]