我国南方牧草生态系统氮素平衡与循环特征研究  

Nitrogen Balance and Cycling in Pasture Ecosystem in South China

作　　者：周静[1] 崔键[2] 王国强[3] 马友华[2] 

机构地区：[1]中国科学院南京土壤研究所,南京210008 [2]安徽农业大学资源环境与信息技术研究所,合肥230036 [3]南京农业大学资源与环境学院,南京210095

出　　处：《土壤》2008年第3期386-391,共6页Soils

基　　金：国家自然科学基金项目(40305019);中国科学院知识创新工程项目(KZCX2-413)资助。

摘　　要：通过在我国南方典型红壤旱地种植牧草马唐,对大气N沉降、氨挥发、径流、淋溶等N素循环量进行了研究。结果表明,马唐的生长期内,不同N肥量处理,红壤旱地牧草生态系统通过肥料和大气沉降输入的N素量为26.28～256.28 kg/hm^2,通过氨挥发、径流、淋溶和牧草吸收输出的N素量为21.95～131.52 kg/hm^2,N素盈余4.33～124.76 kg/hm^2。其中,大气沉降N为26.28 kg/hm^2,占牧草生态系统总输入N的10.85%～22.60%;氨挥发损失N为0.67～5.16 kg/hm^2,占施入N的0.74%～2.24%;径流损失N为0.25～0.42 kg/hm^2,占施入N的0.44%～1.17%:淋溶损失N为0.28～2.86 kg/hm^2,占施入N的0.91%～1.24%。Studies were conducted on nitrogen balance and cycling, such as N deposition, ammonia volatilization, N loss with runoff and leaching in a pasture ecosystem o.f Smooth Crabgrass （Digitaria ischaemum） in typical red soil in South China. Results showed that during the growing period of the grass, regardless of N application rate, the N input of the ecosystem through N fertilization and N atmospheric deposition ranged from 26.28 to 256.28 N kg/hm^2, and the output from 21.95 to 131.52 N kg/hm^2 through ammonia volatilization, loss with runoff and leaching, and plant absorption, thus resulting in an N surplus ranging from 4.33 to 124.76 N kg/hm^2. Atmospheric N deposition during the whole growth of the pasture brought in 26.28 kg/hm^2, accounting for 10.85% - 22.60% of the total N input and N loss through ammonia volatilization was 0.67 - 5.16 kg/hm^2, accounting for 0.74% - 2.24% of the applied N. N loss with runoff was 0.25 - 0.42 kg/hm^2, accounting for 0.44% - 1.17% of the applied N. Meanwhile, N loss through leaching was 0.28 - 2.86 kg/hm^2, accounting for 0.91% - 1.24% of the applied N.

关 键 词：氦沉降 牧草生态系统 氮素平衡与循环 

分 类 号：S14[农业科学—肥料学] S15[农业科学—农业基础科学]