Flooding impact on the distribution of microbial tetraether lipids in paddy rice soil in China  

作　　者：Asma AYARI Huan YANG Shucheng XIE 

机构地区：[1]State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China

出　　处：《Frontiers of Earth Science》2013年第3期384-394,共11页地球科学前沿（英文版）

基　　金：We would thank Dr. WeiHua Ding for analytical assistance with the HPLC-MS equipment. This work was supported by the National Basic Research Program of China （No. 2011CB808800）, the National Natural Science Foundation of China （Grant Nos. 40930210 and 40921062） and the 111 program （B08030） in China.

摘　　要：Isoprenoid and branched glycerol dialkyl glycerol tetraethers （GDGTs） lipids were studied in flooded and non-flooded paddy soil in Wuhan, central China, to examine the response of the GDGTs distribution to the soil flooding. Samples were collected before and after the soil flooding in four specific months. Both core （CL） and intact polar （IPL） GDGTs were quantified. Increase in the abundance of archaeol and caldarchaeol may be indicative of the occurrence of methanogens in the flooded soil. A negative correlation was observed between the ratio of IPL branched GDGT-IIa to GDGT-Ia and the soil pH. The rise of the soil pH in the acid soil is known to be controlled by the redox conditions resulting from flooding. Thus, the branched GDGTs distribution may be controlled by the water content in the paddy soil. In addition, we suggest that the anoxic conditions resulting from flooding may also control the abundance of branched GDGTs relative to crenarchaeol, which in turn results in the increase of branched and isoprenoidal tetraethers （BIT） values, the index for the terrestrial input to the marine sediments.Isoprenoid and branched glycerol dialkyl glycerol tetraethers （GDGTs） lipids were studied in flooded and non-flooded paddy soil in Wuhan, central China, to examine the response of the GDGTs distribution to the soil flooding. Samples were collected before and after the soil flooding in four specific months. Both core （CL） and intact polar （IPL） GDGTs were quantified. Increase in the abundance of archaeol and caldarchaeol may be indicative of the occurrence of methanogens in the flooded soil. A negative correlation was observed between the ratio of IPL branched GDGT-IIa to GDGT-Ia and the soil pH. The rise of the soil pH in the acid soil is known to be controlled by the redox conditions resulting from flooding. Thus, the branched GDGTs distribution may be controlled by the water content in the paddy soil. In addition, we suggest that the anoxic conditions resulting from flooding may also control the abundance of branched GDGTs relative to crenarchaeol, which in turn results in the increase of branched and isoprenoidal tetraethers （BIT） values, the index for the terrestrial input to the marine sediments.

关 键 词：glycerol dialkyl glycerol tetraethers （GDGTs） soil flooding soil pH redox conditions GDGTs distribution branched and isoprenoidal tetraethers （BIT） 

分 类 号：S155.292[农业科学—土壤学] TS218[农业科学—农业基础科学]