摘要
氨挥发是草地生态系统土壤氮素损失的主要途径。掌握氨挥发特征及其与环境要素之间的关系,能够为盐渍化草地养分管理策略制定等提供依据。试验采用间歇密闭室抽气法,测定黄土高原盐渍化草地短期添加氮(0,1,2,4,8,16,24和32 g N·m^(-2)·a^(-1))对盐渍化草地氨挥发的影响。结果表明:草地氨挥发速率与月累积量随氮添加水平的增加而增加;随着氮添加水平的增加,氨挥发的生长季净累积量呈幂函数上升趋势,而氨挥发氮损失率呈幂函数下降趋势。氨挥发速率与土壤湿度、硝态氮含量呈负相关关系(P<0.05),与土壤温度、pH值、铵态氮含量呈正相关关系(P<0.05),与土壤K^(+),Ca^(2+),Mg^(2+),Na^(+)含量无显著相关关系。当氮添加为16 g N·m^(-2)·a^(-1)时,盐渍化草地净初级生产力最高,且氨挥发损失率较小,有利于提高盐渍化草地氮素利用效率、减少环境污染和氮肥损失。
Ammonia volatilization is the main way of soil nitrogen loss in the grassland ecosystem.Grasping the characteristics of ammonia volatilization,as well as the relationship between ammonia volatilization and environmental factors,can provide a basis for the formulation of nutrient management strategies for salinized grassland.The effects of short-term nitrogen addition(0,1,2,4,8,16,24,and 32 g N·m^(-2)·a^(-1))on ammonia volatilization from saline grassland on the Loess Plateau were measured by intermittently closed chamber extraction method.The results demonstrated that the volatilization rate and monthly accumulation of ammonia rose with the amount of nitrogen addition;As the amount of added nitrogen increased,the net accumulation of ammonia volatilization in the growing season showed a power function growth,while the loss rate of ammonia volatile nitrogen decreased in power function.Ammonia volatilization rate was negatively correlated with soil moisture and nitrate nitrogen content(P<0.05),positively correlated with soil temperature,pH value and ammonium nitrogen content(P<0.05),and had no significant relationship with K^(+),Ca^(2+),Mg^(2+),Na^(+) content in soil.When the nitrogen addition was 16 g N·m^(-2)·a^(-1),the net primary productivity of salinized grassland reached the threshold and the ammonia volatilization loss rate was relatively small,which promoted the nitrogen use efficiency and reduced environmental pollution and nitrogen loss of salinized grassland.
作者
赵晓洁
张雄伟
薛江博
杨凯元
陈晓鹏
王常慧
董宽虎
赵祥
ZHAO Xiao-jie;ZHANG Xiong-wei;XUE Jiang-bo;YANG Kai-yuan;CHEN Xiao-peng;WANG Chang-hui;DONG Kuai-hu;ZHAO Xiang(College of Grassland Science,Shanxi Agricultural University,Taigu,Shanxi Province 030801,China;Youyu Loess Plateau Grassland Ecosystem Research Station, Shanxi Agricultural University, Youyu, Shanxi Province 037200, China)
出处
《草地学报》
CAS
CSCD
北大核心
2022年第4期992-999,共8页
Acta Agrestia Sinica
基金
国家自然科学基金(31870438)
山西省优秀人才创新项目(201805D211018)资助。
关键词
氮添加
盐渍化草地
氨挥发
Nitrogen addition
Salinized grassland
Ammonia volatilization
