title: Stable carbon isotope as a signal index for monitoring grassland degradation.
abstract: Grassland degradation due to overgrazing is common in many areas of the world. This study analyzed the potential of the stable carbon isotope (δ(13)C) value as a structural microcosmic index to monitor processes of grassland degradation. The δ(13)C values of plant leaves, roots and soils in non-grazed (NG) and over-grazed (OG) grassland were measured from samples collected from the seven types of grassland in China. We found that the leaf δ(13)C values of palatable species (δ(13)Cleaf) and root δ(13)C values (δ(13)Croot) in OG grasslands were reduced compared with those from NG grasslands. Furthermore, the δ(13)Cleaf and δ(13)Csoil were positive correlation with elevation and latitude, δ(13)Croot was negative correlation with them at high altitude (3000~5000m), and δ(13)Croot and δ(13)Csoil were negative correlation with them at low altitude (0~2000m), respectively. Consequently, tracing of the δ(13)C variations in grassland ecosystem can provide a powerful tool to evaluate the degree of grassland degradation.
authors.affiliation: College of Ecology and Environmental Science, Inner Mongolia Agricultural University, Hohhot 010019, Inner Mongolia, China.
authors.forename: Hongyun
authors.initials: H
authors.lastname: Yao
authors.affiliation: Values for Development Limited, Bury St Edmunds, IP33 3EQ, UK.
authors.forename: Andreas
authors.initials: A
authors.lastname: Wilkes
authors.affiliation: College of Ecology and Environmental Science, Inner Mongolia Agricultural University, Hohhot 010019, Inner Mongolia, China.
authors.forename: Guodong
authors.initials: G
authors.lastname: Zhu
authors.affiliation: College of Ecology and Environmental Science, Inner Mongolia Agricultural University, Hohhot 010019, Inner Mongolia, China.
authors.forename: Hongdan
authors.initials: H
authors.lastname: Zhang
authors.affiliation: College of Ecology and Environmental Science, Inner Mongolia Agricultural University, Hohhot 010019, Inner Mongolia, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Liu
authors.affiliation: College of Ecology and Environmental Science, Inner Mongolia Agricultural University, Hohhot 010019, Inner Mongolia, China.
authors.lastname: Dan Ding
authors.affiliation: Department of Grassland Science, China Agricultural University, Beijing 100193, China.
authors.forename: Xiajie
authors.initials: X
authors.lastname: Zhai
authors.affiliation: Department of Grassland Science, China Agricultural University, Beijing 100193, China.
authors.forename: Shiming
authors.initials: S
authors.lastname: Tang
authors.affiliation: Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Institute of Grassland Science, Chinese Academy of Agricultural Science, Hohhot 010010, China.
authors.forename: Yujuan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Grassland Science, China Agricultural University, Beijing 100193, China.
authors.forename: Ding
authors.initials: D
authors.lastname: Huang
authors.affiliation: College of Ecology and Environmental Science, Inner Mongolia Agricultural University, Hohhot 010019, Inner Mongolia, China.
authors.forename: Chengjie
authors.initials: C
authors.lastname: Wang
mesh_terms: D000531:Altitude; D002247:Carbon Isotopes / Q000032:analysis*; D017753:Ecosystem; D004784:Environmental Monitoring; D065948:Grassland; D018515:Plant Leaves / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*
chemical_list: D002247:Carbon Isotopes; D012987:Soil