Variability of soil organic carbon reservation capability between coastal salt marsh and riverside freshwater wetland in Chongming Dongtan and its microbial mechanism  

作　　者：Yu Hu Yanli Li Lei Wang Yushu Tang Jinhai Chen Xiaohua Fu Yiquan Le Jihua Wu 

机构地区：[1]State Key Laboratory of Pollution Control and Resource Reuse,College of Environmental Science and Engineering,Tongji University,Shanghai 200092,China [2]School of Life Science,Fudan University,Shanghai 200433,China

出　　处：《Journal of Environmental Sciences》2012年第6期1053-1063,共11页环境科学学报（英文版）

基　　金：supported by the National Major Scientific and Technological Project of China (No.2010BAK69B13,2010BAK69B14);the Major Project of the Shanghai Scientific and Technological Committee(No. 10dz1200903,10dz1200700)

摘　　要：Two representative zones in Chongming Dongtan which faced the Yangtze River and East China Sea respectively were selected to study the variability of soil organic carbon （SOC） reservation capability between coastal wetland and riverside wetland in the Chongming Dongtan wetland as well as its mechanism by analyzing soil characteristics and plant biomass.The results showed the SOC content of riverside wetland was only 48.61% （P=0.000 〈 0.05） that of coastal wetland.As the organic matter inputs from plant litter of the coastal wetland and riverside wetland were approximately the same,the higher soil microbial respiration （SMR） of riverside wetland led to its lower SOC reservation capability.In the riverside wetland,the high soil microbial biomass,higher proportion of β-Proteobacteria,which have strong carbon metabolism activity and the existence of some specific aerobic heterotrophic bacteria such as Bacilli and uncultured Lactococcus,were the important reasons for the higher SMR compared to the coastal wetland.There were additional differences in soil physical and chemical characteristics between the coastal wetland and riverside wetlands.Path analysis of predominant bacteria and microbial biomass showed that soil salinity influenced β-Proteobacteria and microbial biomass most negatively among these physical and chemical factors.Therefore the low salinity of the riverside area was suitable for the growth of microorganisms,especially β-Proteobacteria and some specific bacteria,which led to the high SMR and low SOC reservation capability when compared to the coastal area.Two representative zones in Chongming Dongtan which faced the Yangtze River and East China Sea respectively were selected to study the variability of soil organic carbon （SOC） reservation capability between coastal wetland and riverside wetland in the Chongming Dongtan wetland as well as its mechanism by analyzing soil characteristics and plant biomass.The results showed the SOC content of riverside wetland was only 48.61% （P=0.000 〈 0.05） that of coastal wetland.As the organic matter inputs from plant litter of the coastal wetland and riverside wetland were approximately the same,the higher soil microbial respiration （SMR） of riverside wetland led to its lower SOC reservation capability.In the riverside wetland,the high soil microbial biomass,higher proportion of β-Proteobacteria,which have strong carbon metabolism activity and the existence of some specific aerobic heterotrophic bacteria such as Bacilli and uncultured Lactococcus,were the important reasons for the higher SMR compared to the coastal wetland.There were additional differences in soil physical and chemical characteristics between the coastal wetland and riverside wetlands.Path analysis of predominant bacteria and microbial biomass showed that soil salinity influenced β-Proteobacteria and microbial biomass most negatively among these physical and chemical factors.Therefore the low salinity of the riverside area was suitable for the growth of microorganisms,especially β-Proteobacteria and some specific bacteria,which led to the high SMR and low SOC reservation capability when compared to the coastal area.

关 键 词：soil organic carbon carbon reservation capability community diversity coastal wetland riverside wetland ChongmingDongtan 

分 类 号：S153.621[农业科学—土壤学] Q959.727[农业科学—农业基础科学]