Tang Guo-Yong, Wu Jin-Shui, Su Yi-Rong, Zheng Hua, Li Kun
Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China.
Huan Jing Ke Xue. 2009 Jul 15;30(7):2047-52.
The contrasts of the content and density characteristics of surface soil organic carbon among four typical landscapes of subtropical region in China were investigated. The results show that the area-weighted mean content of SOC varies widely with landscapes and the highest mean content is present in the lacustrine plain landscape (25.10 g x kg(-1)), followed by the karst landscape (20.84 g x kg(-1)) and mountainous landscape (17.75 g x kg(-1)), whereas the lowest occurs in the hilly red soil landscape (12.07 g x kg(-1)). The coefficient of variation of SOC content ranges from 24.06% to 43.76%, being moderate variation. The main distribution ranges of SOC content are higher than 20 g x kg(-1) in the lacustrine plain landscape and lower than 20 g x kg(-1) in the other three landscapes. The sequence of SOC density in the four landscapes is highly consistent with the sequence of SOC content, and the sequence is as follows: lacustrine plain landscape (6.12 kg x m(-2) > karst landscape (4.30 kg x m(-2)) > mountainous landscape (4.25 kg x m(-2)) > hilly red soil landscape (3.04 kg x m(-2)). The results reveal that the difference of soil parent material, cultivation strength, topography and proportion of land use may be the main reasons caused the variation of SOC content among the four landscapes. Surface soils in typical landscapes of subtropical region are important carbon pool in China.
研究了中国亚热带地区四种典型景观表层土壤有机碳含量和密度特征的差异。结果表明，土壤有机碳的面积加权平均含量随景观类型变化差异较大，其中湖积平原景观的平均含量最高（25.10 g x kg(-1)），其次是喀斯特景观（20.84 g x kg(-1)）和山地景观（17.75 g x kg(-1)），而最低的是赤红壤丘陵景观（12.07 g x kg(-1)）。土壤有机碳含量的变异系数在24.06%至43.76%之间，属于中等变异。土壤有机碳含量的主要分布范围在湖积平原景观中高于20 g x kg(-1)，在其他三种景观中低于20 g x kg(-1)。四种景观中土壤有机碳密度的排序与土壤有机碳含量的排序高度一致，顺序如下：湖积平原景观（6.12 kg x m(-2)）>喀斯特景观（4.30 kg x m(-2)）>山地景观（4.25 kg x m(-2)）>赤红壤丘陵景观（3.04 kg x m(-2)）。结果表明，土壤母质、耕作强度、地形和土地利用比例的差异可能是导致四种景观土壤有机碳含量变异的主要原因。亚热带地区典型景观的表层土壤是中国重要的碳库。
