Soil organic carbon and nitrogen content of density fractions and effect of meadow degradation to soil carbon and nitrogen of fractions in alpine Kobresia meadow

查看全文 作　　者：WANG [1]WenYing;WANG [2]QiJi;LU [1]ZiYu

机构地区：[1]Department of Life Sciences,Qinghai Normal University,Xining 810008,China;[2]Northwest Institute of Plateau Biology,Chinese Academy of Sciences,Xining 810008,China

出　　处：《Science China Earth Sciences》索引2009年第52卷第5期,共9页

基　　金：Supported by National Natural Science Foundation of China (Grant No. 30660120);Science Support Project in the Source Region of the Three Rivers (Grant No. 2005-SN-2) 摘　　要：This research was conducted on the non-disturbed native alpine Kobresia meadow(YF) and the severely degraded meadow(SDL) of Dari County of Qinghai Province.By a density fractionation approach,each soil sample was divided into two fractions:light fraction(LF) and heavy fraction(HF).The obtained fractions were analyzed for organic carbon(OC) and nitrogen(N) concentrations.The results showed:(1) the OC concentration in HF and LF was 3.84% and 28.63% respectively while the nitrogen concentration in HF and LF was 0.362% and 1.192% respectively in 0-10 cm depth.C:N ratio was 10.6 in HF and 23.8 in LF respectively.(2) As far as the ratio of OC in given fraction to that in gross sample was concerned,dominance of OC in HF was obvious in the whole soil profile.OC in HF increased from 78.95% to 90.33%,while OC in LF decreased from 21.05% to 9.68% with depths.(3) Soil total OC amounted to 47.47 in YF while 17.63 g.kg-1 in SDL,in which the OC content in HF decreased from 37.31 to 16.01 g.kg-1 while OC content in LF decreased from 10.01 to 1.62 g.kg-1.In other words,results of OC and N content show meadow degradation led to the loss of 57% OC in HF and 84% OC in LF from originally native ecosystem on alpine meadow.In addition,meadow degradation led to the loss of 43% N in HF and 79% N in LF from originally native ecosystem on alpine meadow.(4) The main reason for loss of C and N in LF during meadow degradation was not attributed to the decrease of OC and N concentration in LF and LF,but to the decrease in LF dry weight.Loss of N was far lower than loss of C in HF.This may suggest that there is difference in protection mode of C and N in HF. 关键词：alpine Kobresia MEADOW DENSITY fraction SOIL organic carbon SOIL NITROGEN MEADOW DEGRADATION

相关文献

参考文献（32）
引证文献（11）
耦合文献（353）

参考文献(32)

引证文献(11)

耦合文献(353)

互联网出版许可证新出网证(渝)字10号全国400电话 - 免长途话费

Soil organic carbon and nitrogen content of density fractions and effect of meadow degradation to soil carbon and nitrogen of fractions in alpine Kobresia meadow

参考文献(32)

引证文献(11)

耦合文献(353)

用户提示