放牧对不同类型草原土壤碳氮及其稳定同位素的影响  

Effects of Grazing on Carbon,Nitrogen,and Their Stable Isotopes in Soils of Different Grassland Types

作　　者：刘海洋[1,2] 王占义[1,2] 高翠萍[1,2] 杨昌祥 张春英 王成杰[1,2] LIU Haiyang;WANG Zhanyi;GAO Cuiping;YANG Changxiang;ZHANG Chunying;WANG Chengjie(College of Grassland Science,Inner Mongolia Agricultural University,Hohhot 010018,China;Key Laboratory of Grassland Resources,the Ministry of Education,Hohhot 010018,China;Forestry and Grassland Bureau of Huade,Ulanqab,Inner Mongolia,Ulanqab 013350,China)

机构地区：[1]内蒙古农业大学草业学院,内蒙古呼和浩特010018 [2]内蒙古农业大学草原资源教育部重点实验室,内蒙古呼和浩特010018 [3]内蒙古乌兰察布市化德县林业与草原局,内蒙古乌兰察布013350

出　　处：《中国草地学报》2024年第10期14-22,共9页Chinese Journal of Grassland

基　　金：内蒙古自治区“科技兴蒙”国际合作引导项目(2021CG-0020);国家自然科学基金项目(31960357,31460125)。

摘　　要：为探究不同草原类型生态系统碳氮元素对重度放牧的响应,本研究以平原丘陵草原、平原丘陵荒漠草原和沙地荒漠草原3种草原类型为对象,通过测定围封和重度放牧下土壤有机碳、全氮、稳定碳氮同位素及土壤温湿度等指标,探究放牧处理对不同类型草原碳氮元素的影响。结果表明:(1)重度放牧显著降低了3种类型草原土壤有机碳、全氮含量(P<0.05),重度放牧条件下土壤稳定碳同位素和土壤稳定氮同位素值有降低的趋势;(2)土壤稳定碳同位素值与土壤含水量存在极显著负相关性(P<0.01),土壤有机碳、全氮含量及土壤稳定氮同位素值均与土壤含水量存在极显著正相关性(P<0.01)。重度放牧对不同类型草原碳氮养分含量造成了不同程度的影响,其中对平原丘陵草原影响较大,不利于土壤有机碳和全氮的积累。To investigate the response of carbon and nitrogen to heavy grazing in different types of grassland ecosystem,this research focused on three different grassland types,plain hilly steppe,plain hilly desert steppe,and sandy desert steppe.Soil organic carbon,soil total nitrogen,soil carbon and nitrogen stable isotopes,soil temperature,and soil moisture were measured under no grazing fence and heavy graz⁃ing conditions.Results revealed that(1)Soil organic carbon and soil total nitrogen were significantly reduced(P<0.05)under heavy grazing for three grassland types.There is a trend of decreasing for soil carbon and nitrogen stable isotopes under heavy grazing.(2)Correlation of soil carbon stable isotope with soil moisture was significantly negative(P<0.01),whereas soil organic carbon and soil total nitrogen were positively correlated with soil moisture(P<0.01).Heavy grazing had different effect levels for differ⁃ent grassland types on carbon and nitrogen nutrition.Plain hilly steppe was affected the most by heavy graz⁃ing in three grassland types,which inhibited accumulation of soil organic carbon and soil total nitrogen.

关 键 词：放牧 草原类型 稳定碳氮同位素 土壤有机碳 土壤全氮 

分 类 号：S812.2[农业科学—草业科学]