不同土地利用方式下黑土氮素含量变化特征  

Effect of Land Use on Nitrogen Content in Black Soil

作　　者：朱霞[1,2] 韩晓增[1] 

机构地区：[1]中国科学院东北地理与农业生态研究所,黑龙江哈尔滨150081 [2]中国科学院研究生院,北京100039

出　　处：《江苏农业学报》2008年第6期843-847,共5页Jiangsu Journal of Agricultural Sciences

基　　金：中国科学院知识创新工程重要方向项目(KZCX2-YW-407);国家重点基础研究发展计划(“973”计划)项目(2005CB121101)

摘　　要：利用中国科学院海伦农业生态实验站长期定位试验,比较不同土地利用方式下黑土全氮、碱解氮、铵态氮和硝态氮的变化特征;同时研究不同土样种植作物(玉米)所表现的土壤生产力。结果表明:(1)不同土地利用方式下全氮含量存在显著差异(P<0.05),自然土壤植被被破坏或转为农田,土壤全氮含量持续下降,但农田化肥和有机肥配施后,土壤全氮含量显著增加;草地经过20年的植被恢复,土壤全氮含量显著高于农田化肥和无肥处理,土壤氮库储量显著提高。(2)土地利用变化对土壤碱解氮和铵态氮含量影响显著,草地、化肥+有机肥耕地土壤碱解氮和铵态氮含量显著高于裸地、无肥耕地和化肥耕地,而草地土壤硝态氮含量则显著低于裸地、无肥耕地、化肥耕地和化肥+有机肥耕地。(3)不同土地利用方式下的土壤,在种植玉米后,玉米相对生物量最大的为化肥+有机肥耕地,其次为草地和化肥耕地,最低为无肥耕地。Long-term position experiments were conducted in Hailun Agricultural Ecology Station of Chinese Academy of Sciences together with lab incubation with aims to examine the effects of land use on total N, alkaline N, ammonium N, nitrate N, and variations of soil productivity by planting maize in the soils tested. The results showed that i） Soils different in land use differed significantly（P 〈 0. 05） in total nitrogen（TN）. Natural ecosystems, subjected to human disturbance or transferred into cropland, suffered TN losses, however, application of chemical fertilizer plus organic manure increased significantly TN contents in cropland. Soil nitrogen storage of black soil under grassland has been increasing in the past 20 years of vegetation rehabilitation. Ⅱ） Changes of land use had significant effect on contents of soil alkaline N and ammonium N. The soil alkaline N and ammonium N in grassland, farmland with chemical fertilizer plus organic manure were all higher than that in bareland, farmeland with no fertilizer and farmland with chemical fertilizer. However, the soil nitrate in grassland was obviously lower than that in bareland, farmland with no fertilizer, farmland with chemical fertilizer and farmland with chemical fertilizer plus organic manure, iii） After planting maize in soil different in land use, the highest relative biomass production was farmland with chemical fertilizer plus organic manure and the lowest of relative biomass production was farmland with no fertilizer.

关 键 词：土地利用方式 氮素 黑土 

分 类 号：S158.3[农业科学—土壤学]