[Difference and its formation cause in soil organic carbon accumulation capability of two typical tidal wetlands at Dongtan of Chongming Island in Shanghai].
Through the analyses of soil organic carbon content and vegetation input, this paper studied the difference in soil organic carbon accumulation capability of two typical tidal wetlands, one (A) was on the erosion bank with Phragmites communis and sandy loam soil at southeast Dongtan in Shanghai, and the other (B) was on the alluvial bank with P. communis, Spartina alterniflora, and clay soil at northeast Dongtan of Chongming Island. The main formation causes of the difference were analyzed based on the determinations of soil microbial activities and physical-chemical properties. In A, the average soil total organic carbon content was 46.10% (P < 0.05) of that in B, while the annual aboveground vegetation dry mass was only 9.16% lower than that in B, illustrating that the soil organic carbon output was higher in A than in B. The total count of soil bacteria and the activities of soil catalase and invertase in A were 3.82 times (P < 0.05), 46.81% (P < 0.05), and 34.33% (P < 0.05) higher than those in B, respectively, and the soil microbial respiration in A was also higher than that in B, which indicated that the stronger soil microbial C-metabolic activity in A was the main cause inducing the lower soil organic carbon accumulation capability. The sandy loam soil in A had higher porosity and lower salinity and moisture, being favorable to the growth of soil microbes and the decomposition of soil organic carbon, while the clay soil in B had higher salinity and moisture but lower microbial activity, leading to the weaker soil organic carbon decomposition and higher organic carbon accumulation.
State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China. birdrain@hotmail.com
Yan-Li
YL
Li
Chun-Ling
CL
Xiao
Lei
L
Wang
Wen-Quan
WQ
Zhang
Shi-Ping
SP
Zhang
Hong-Li
HL
Wang
Xiao-Hua
XH
Fu
Yi-Quan
YQ
Le
D001419:Bacteria / Q000378:metabolism; D002244:Carbon / Q000378:metabolism*; D002681:China; D009930:Organic Chemicals / Q000378:metabolism*; D006109:Poaceae / Q000378:metabolism*; D012987:Soil / Q000032:analysis*; D012988:Soil Microbiology; D053833:Wetlands
D009930:Organic Chemicals; D012987:Soil; D002244:Carbon