摘要
采用化学分析和变性梯度凝胶电泳(DGGE)技术,从表层土壤的微生物活性及基因多样性角度研究了长期不同施肥制度对紫色水稻土硝化作用及硝化细菌群落结构的影响。结果表明,经过24a长期定位肥料试验,不同施肥处理土壤pH和硝化作用均不相同,施肥在降低土壤pH的同时会增加土壤的硝化作用;不同作物种植方式也会影响土壤pH和硝化作用,紫色水稻土旱季pH和硝化作用均大于淹水土壤。施用化肥以及化肥配施有机肥不仅可以提高土壤硝化作用,也能够改变土壤中硝化细菌的群落结构;与长期单施化肥相比,长期化肥配施农家肥不仅提高了土壤的硝化作用,而且提高了土壤硝化细菌的分子多样性。UPGMA聚类分析显示,10种不同施肥处理的聚类图也不同;在水稻收割后,M,NM,NPM与NPKM聚在一个群里,CK,N和NP聚在第二个群里,而NPK,NPKMZn和NPKMMn聚成第三个群;在小麦收割后,M,NM,NPM,N,NP和NPKMMn肥料影响下的硝化细菌群落聚成一个群,NPK,NPKMZn和NPKMMn肥下的硝化细菌聚在一起,形成第二个群,对照(无肥)下的硝化细菌群落单独成为第三个群。应用PCR-DGGE技术可以揭示石灰性紫色水稻土上24a不同施肥及作物栽培管理措施下的硝化细菌分子群落结构特点。
Chemical analysis and denaturing gradient gel electrophoresis （DGGE） were employed to determine the influence of long-term application of fertilizers on nitrification rates and nitrobacteria community in a calcareous purple paddy soil under rice-wheat rotations. Results showed that both pH and nitrification rates of the same soil varied substantially after long-term treatments with various fertilizers. Generally, soil amended with any fertilizers tended to reduce soil pH but increase nitrification rates compared to the control without fertilization （CK）. The pH values and the nitrification rates of the soil appeared to be lower under rice rotation than those of the same soil under wheat rotation. Fertilizer amendment not only increased the soil nitrification rates but also altered the nitrobacteria community structures. As compared to the mineral fertilizer treatments, soil amendment with a combination of the mineral fertilizers with farmyard manure increased the rates of soil nitrification and the diversity of the nitrobacteria community as revealed by Unweighted Pair Group Method Clustering Analysis （UPGMA） of the DGGE banding patterns and cluster analysis of the DGGE profiles. In the soil under rice rotation, the nitrobacteria communities in soil amended with mineral nitrogen （N） or nitrogen-phosphor （NP） fertilizers was in the same cluster as that of the control （i. e. , CK）. Nitrobacteria communities exposed to the fertilizer treatments with manure [manure only （M）, nitrogen plus manure （NM）, nitrogen and phosphor plus manure （NPM）, and nitrogen, phosphor and potassium plus manure （NPKM）] fell into the second group while that exposed to the NPK, NPKMZn, NPKMMn treatments was in the third group. In the soil under wheat rotation conditions, nitrobacteria communities in M, NM, NPM, N, NP and NPKMMn fertilizer treatments were clustered into one group, those in NPK, NPKMZn and NPKMMn to another group, and those in CK as a single cluster. The study demonstrated that PCR-DGGE technique was suitable for characterizing the nitrobacteria community of the calcareous purple paddy soil under different fertilizer treatments and crop rotations.
出处
《生态学报》
CAS
CSCD
北大核心
2008年第5期2123-2130,共8页
Acta Ecologica Sinica
基金
国家科技支撑计划课题资助项目(2006BAD05B06
2006BAD02A14-13)~~
关键词
长期定位施肥
DGGE
硝化作用
硝化细菌群落结构
稻麦轮作
Long-term fertilization
DGGE
nitrification
nitrification bacteria community
rice-wheat rotation
