不同氮输入对湿地草甸沼泽土N_2O排放和有机碳矿化的影响  

Effects of nitrogen input on meadow marsh soil N_2O emission and organic carbon mineralization

作　　者：李英臣[1,2] 宋长春 侯翠翠[1,2] 宋艳宇[1,2] 

机构地区：[1]中国科学院东北地理与农业生态研究所,长春130012 [2]中国科学院研究生院,北京100049

出　　处：《生态学杂志》2010年第11期2091-2096,共6页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(40930527;40771189);国家重点基础研究发展计划项目(2009CB421103);中国科学院重要方向性资助项目(KZCX2-YW-JC301)

摘　　要：通过室内培养实验,研究了不同氮输入梯度下(N0:0mg·g-1,N1:0.1mg·g-1,N2:0.2mg·g-1,N3:0.5mg·g-1)湿地草甸沼泽土N2O排放和有机碳矿化特征,并分析了土壤微生物量碳、氮变化规律。整个培养期(23d)内,N0、N1、N2和N3处理N2O排放总量分别为91.12、133.02、147.75和303.45μg.kg-1,随氮输入量增大而增大,表明氮输入对N2O排放产生促进作用;氮输入处理的有机碳矿化速率在整个培养期除最后培养阶段外均低于对照,表明氮输入对有机碳矿化有一定的抑制作用;各氮输入处理土壤微生物量碳降低,与对照差异显著(P<0.05),但各处理间差异未达到显著水平,土壤微生物量氮随氮输入量增大呈线性增加,各处理间差异显著(P<0.05),表明氮输入影响土壤微生物结构和组成,具体影响机理须进一步探讨。A laboratory incubation test was conducted to study the effects of different nitrogen inputs（N0：0 mg·g-1;N1：0.1 mg·g-1;N2：0.2 mg·g-1;N3：0.5 mg·g-1）on the characteristics of N2O emission and organic carbon mineralization in a meadow marsh soil,and the variation patterns of soil microbial carbon and nitrogen.During the incubation period（23 d）,the N2O emission in treatments N0,N1,N2,and N3 was 91.12,133.02,147.75,and 303.45 μg·kg-1,respectively,illustrating that nitrogen input promoted soil N2O emission.Except at the late phase of incubation,the mineralization rate of soil organic carbon under nitrogen input lowered,suggesting that nitrogen input restrained the mineralization of soil organic carbon to some degree.Compared with treatment N0,the soil microbial biomass carbon in treatments N1,N2,and N3 was significantly lower（P0.05）,but no significant difference was observed among the latter three treatments.Soil microbial biomass nitrogen increased linearly with increasing nitrogen input,and there were significant differences among different nitrogen inputs（P0.05）.Our results suggested that supplying exogenous nitrogen affected the structure and composition of soil microbes,and the related mechanisms should be studied further.

关 键 词：氮输入 N2O排放 有机碳矿化 微生物量碳 微生物量氮 

分 类 号：S812[农业科学—草业科学]