Labile organic carbon（LOC） is one of the most important indicators of soil organic matter quality and dynamics elevation and plays important function in the Tibetan Plateau climate. However, it is unknown what the s...Labile organic carbon（LOC） is one of the most important indicators of soil organic matter quality and dynamics elevation and plays important function in the Tibetan Plateau climate. However, it is unknown what the sources and causes of LOC contamination are. In this study, soil organic carbon（SOC）, total nitrogen（TN）, microbial biomass carbon（MBC）, microbial biomass nitrogen（MBN） and LOC were analyzed based on different soil horizons and elevations using turnover time in an experimental site（3700 m to 4300 m area） in Sygera. SOC and LOC in higher-elevation vegetation types were higher than that of in lower-elevation vegetation types. Our results presented that the soil microbial biomass carbon（SMBC） and soil microbial biomass nitrogen（SMBN）were positively correlated with SOC. The content of easily oxidized carbon（EOC）, particulate organic carbon（POC） and light fraction organic carbon（LFOC） decreased with depth increasing and the content were the lowest in the 60 cm to 100 cm depth.The total SOC, ROC and POC contents decreased with increasing soil horizons. The SOC, TN, MBC and MBN contents increased with increasing altitude in the Sygera Mountains. The MBC and MBN contents weredifferent with the changes of SOC（p＆lt;0.05）,meanwhile, both LFOC and POC were related to total SOC（p＆lt;0.05）. The physical and chemical properties of soil, including temperature, humidity, and altitude,were involved in the regulation of SOC, TN, MBC,MBN and LFOC contents in the Sygera Mountains,Tibetan Plateau.展开更多
Soils under broad-leaved,masson pine,Chinese fir and bamboo forests in the area of Huzhou,Zhejiang were collected and analyzed in January 2000.Soil total organic carbon(TOC) under broad-leaved and bamboo forests were ...Soils under broad-leaved,masson pine,Chinese fir and bamboo forests in the area of Huzhou,Zhejiang were collected and analyzed in January 2000.Soil total organic carbon(TOC) under broad-leaved and bamboo forests were considerately higher than(P<0.01)those under masson pine and Chinese fir.There was no significant differences in microbial biomass carbon(MBC) in soils among various types of vegetation,however,the bamboo stands constituted a lower(P<0.05) proportion of MBC compared with broad-leaved forest,masson pine and Chinese fir were similar in MBC to TOC,indicating that intensive management in bamboo stand reduced the proportion of soil MBC in TOC.MBC in soils under broad-leaved forest,masson pine forest and Chinese fir forest had strong positive relationships with the corresponding TOCs,the correlation coefficients were respective 0.744 4,0.648 4 and 0.552 1.It was found that soil easily oxidizable carbon(EOC) in bamboo forest was much higher than those in the other 3 forests.The higher percentages of EOC were detected from soils under bamboo forest(52.40%) and Chinese fir forest(50.50%) compared with broad-leaved forest(48.90%) and masson pine forest(45.74%).Soil EOC for all 4 forests were closely correlated(P<0.01)with the correspondent TOCs.展开更多
基金supported by CFERN & GENE Award Funds on Ecological Paper
文摘Labile organic carbon（LOC） is one of the most important indicators of soil organic matter quality and dynamics elevation and plays important function in the Tibetan Plateau climate. However, it is unknown what the sources and causes of LOC contamination are. In this study, soil organic carbon（SOC）, total nitrogen（TN）, microbial biomass carbon（MBC）, microbial biomass nitrogen（MBN） and LOC were analyzed based on different soil horizons and elevations using turnover time in an experimental site（3700 m to 4300 m area） in Sygera. SOC and LOC in higher-elevation vegetation types were higher than that of in lower-elevation vegetation types. Our results presented that the soil microbial biomass carbon（SMBC） and soil microbial biomass nitrogen（SMBN）were positively correlated with SOC. The content of easily oxidized carbon（EOC）, particulate organic carbon（POC） and light fraction organic carbon（LFOC） decreased with depth increasing and the content were the lowest in the 60 cm to 100 cm depth.The total SOC, ROC and POC contents decreased with increasing soil horizons. The SOC, TN, MBC and MBN contents increased with increasing altitude in the Sygera Mountains. The MBC and MBN contents weredifferent with the changes of SOC（p＆lt;0.05）,meanwhile, both LFOC and POC were related to total SOC（p＆lt;0.05）. The physical and chemical properties of soil, including temperature, humidity, and altitude,were involved in the regulation of SOC, TN, MBC,MBN and LFOC contents in the Sygera Mountains,Tibetan Plateau.
文摘Soils under broad-leaved,masson pine,Chinese fir and bamboo forests in the area of Huzhou,Zhejiang were collected and analyzed in January 2000.Soil total organic carbon(TOC) under broad-leaved and bamboo forests were considerately higher than(P<0.01)those under masson pine and Chinese fir.There was no significant differences in microbial biomass carbon(MBC) in soils among various types of vegetation,however,the bamboo stands constituted a lower(P<0.05) proportion of MBC compared with broad-leaved forest,masson pine and Chinese fir were similar in MBC to TOC,indicating that intensive management in bamboo stand reduced the proportion of soil MBC in TOC.MBC in soils under broad-leaved forest,masson pine forest and Chinese fir forest had strong positive relationships with the corresponding TOCs,the correlation coefficients were respective 0.744 4,0.648 4 and 0.552 1.It was found that soil easily oxidizable carbon(EOC) in bamboo forest was much higher than those in the other 3 forests.The higher percentages of EOC were detected from soils under bamboo forest(52.40%) and Chinese fir forest(50.50%) compared with broad-leaved forest(48.90%) and masson pine forest(45.74%).Soil EOC for all 4 forests were closely correlated(P<0.01)with the correspondent TOCs.
