Grassland degradation is one of the major ecological problems in the western part of Jilin Province; grassland degradation changes the carbon balance of grassland ecosystem. By taking different succession stages of grassland degradation in the western part of Jilin Province as the research object, 40 sample plots were selected, and 160 soil samples were collected for further experimental analysis via wild plots investigation in Jiangjiadian of Da'an City. The following results are achieved through determining soil characteristic and investigating vegetation community. As converse succession is on the way, the water ratio of soil and coverage is decreasing, soil permeability is worse while vegetation biomass and biology diversity first go up and then fall. In different stage of degradation succession, organic carbon density in 40cm soil is increased from 47.72 t/hm2 in Leymus chinense to 48.46 t/hm2 in Carex duiuscula, and then the density is cutting down to 27.44 t/hm2 in salt flat. Converse succession caused by grassland degradation made the organic carbon density in surface soil (0—40cm) decrease 8.45, 5.72, 3.68, and 1.74t/hm2, respectively. The conclusions are listed as follows: Grassland degradation causes the large influence of organic carbon on surface soil, meanwhile has little influence on deep soil. It is not a simple carbon exposed process. Certain grassland degradation might increase the carbon reserves caused by artificial or natural impacts, while excessive degradation could accelerate the loss of grassland carbon store.
HAN Weizheng;TANG Jie;LI Zhaoyang;LI Na;LIU Sen
. Changes of Surface Soil Organic Carbon in Different Degradation Succession Stages of Grassland Ecosystem in the Western Part of Jilin Province[J]. Science & Technology Review, 2011
, 29(13)
: 40
-43
.
DOI: 10.3981/j.issn.1000-7857.2011.13.005