中国地理科学(英文版) ›› 2010, Vol. 20 ›› Issue (3): 209-217.doi: 10.1007/s11769-010-0209-7

• 论文 • 上一篇    下一篇

Freeze-thaw Effects on Sorption/Desorption of Dissolved Organic Carbon in Wetland Soils

YU Xiaofei1,2, ZHANG Yuxia1, ZHAO Hongmei1,2, LU Xianguo1, WANG Guoping1   

  1. 1. Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130012, China;
    2. Graduate University of the Chinese Academy of Sciences, Beijing 100049, China
  • 收稿日期:2009-09-11 修回日期:2010-01-28 出版日期:2010-04-01 发布日期:2010-04-23
  • 通讯作者: WANG Guoping.E-mail:wangguoping@neigae.ac.cn E-mail:wangguoping@neigae.ac.cn
  • 基金资助:

    Under the auspices of Knowledge Innovation Programs of Chinese Academy of Sciences (No.KZCX2-YW-309);National Natural Science Foundation of China (No.40871089, 40830535)

Freeze-thaw Effects on Sorption/Desorption of Dissolved Organic Carbon in Wetland Soils

YU Xiaofei1,2, ZHANG Yuxia1, ZHAO Hongmei1,2, LU Xianguo1, WANG Guoping1   

  1. 1. Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130012, China;
    2. Graduate University of the Chinese Academy of Sciences, Beijing 100049, China
  • Received:2009-09-11 Revised:2010-01-28 Online:2010-04-01 Published:2010-04-23
  • Supported by:

    Under the auspices of Knowledge Innovation Programs of Chinese Academy of Sciences (No.KZCX2-YW-309);National Natural Science Foundation of China (No.40871089, 40830535)

摘要:

The effects of freeze-thaw cycles on sorption/desorption of dissolved organic carbon (DOC) in two wetland soils and one reclaimed wetland soil were investigated. DOC concentrations added were 0-600 mg/L. Laboratory incubations of sorption/desorption of DOC had been carried out at -15℃ for 10 h, and then at +5℃ for 13 h. Soil samples were refrozen and thawed subsequently for 5 cycles. Initial Mass model was used to describe sorption behavior of DOC. The results indicate that freeze-thaw cycles can significantly increase the sorption capacity of DOC and reduce the desorption capacity of DOC in the three soils. The freeze-thaw effects on desorption of DOC in soils increase with the increasing freeze-thaw cycles. The conversion of natural wetlands to soybean farmland can decrease the sorption capacity and increase the desorption capacity of DOC in soils. Global warming and reclamation may increase DOC release, and subsequently increase the loss of carbon and the emission of greenhouse gas.

关键词: DOC, sorption, desorption, freeze-thaw, wetland soils

Abstract:

The effects of freeze-thaw cycles on sorption/desorption of dissolved organic carbon (DOC) in two wetland soils and one reclaimed wetland soil were investigated. DOC concentrations added were 0-600 mg/L. Laboratory incubations of sorption/desorption of DOC had been carried out at -15℃ for 10 h, and then at +5℃ for 13 h. Soil samples were refrozen and thawed subsequently for 5 cycles. Initial Mass model was used to describe sorption behavior of DOC. The results indicate that freeze-thaw cycles can significantly increase the sorption capacity of DOC and reduce the desorption capacity of DOC in the three soils. The freeze-thaw effects on desorption of DOC in soils increase with the increasing freeze-thaw cycles. The conversion of natural wetlands to soybean farmland can decrease the sorption capacity and increase the desorption capacity of DOC in soils. Global warming and reclamation may increase DOC release, and subsequently increase the loss of carbon and the emission of greenhouse gas.

Key words: DOC, sorption, desorption, freeze-thaw, wetland soils