地理学报 ›› 2004, Vol. 59 ›› Issue (4): 505-513.doi: 10.11821/xb200404003

• 土壤碳蓄量 • 上一篇    下一篇

荒漠化重建地区土壤有机碳时空动态特征——以陕西省榆林市为例

程淑兰1,2, 欧阳华1, 牛海山2, 王琳1,2, 田玉强1,2, 张锋1,2, 高俊琴1,2   

  1. 1. 中国科学院地理科学与资源研究所,北京 100101;
    2. 中国科学院研究生院,北京 100039
  • 收稿日期:2003-10-30 修回日期:2004-03-11 出版日期:2004-07-25 发布日期:2004-07-25
  • 作者简介:程淑兰 (1977-),女,博士生。主要研究方向为陆地生态系统格局与过程。 E-mail: chengsl@igsnrr.ac.cn
  • 基金资助:

    国际科技合作重点项目计划 (2001DFDF0004)

Temporal-spatial Dynamic Analysis of Soil Organic Carbon in Inversed Desertification Area: a case study in Yulin County, Shaanxi Province

CHENG Shulan1,2, OUYANG Hua1, NIU Haishan2   

  1. 1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China;
    2. Graduate School of Chinese Academy of Sciences, Beijing 100039, China
  • Received:2003-10-30 Revised:2004-03-11 Online:2004-07-25 Published:2004-07-25
  • Supported by:

    International Key Project of Technological Cooperation, No.2001DFDF0004

摘要:

以陕西省榆林市这一典型区为例探讨干旱、半干旱荒漠化重建地区SoC时空动态特征及其驱动因素。数据基础为1982年土壤普查和2003年重复采样。结果表明:(1) 在耕层 (0~20 cm)、1 m深 (0~100 cm) 和全剖面 (母质层以上整个土体) 等三个剖面层次上,土壤有机碳密度(SoCD)和储量(SoCS)时空动态分异明显,其中耕层最为显著。(2) 在区域水平上,耕层、1 m深和全剖面SoCS分别增加10.12 Gg、19.06 Gg和20.10 Gg,其中东南部丘陵沟壑区显著高于西北部风沙草滩区。(3) 在土类水平上,风沙土类中各土种SoCD及其变化悬殊,其中流动风沙土和半固定风沙土SoCD最低、增加量最小,固定风沙土初始SoCD最高、减少量最大;反之,黄绵土类中各土种SoCD较高,增加量显著。该研究证明植树造林种草、可持续农业耕垦等土地利用和管理方式的变更能显著提高荒漠化地区土壤固碳能力。

关键词: 土壤有机碳, 土地荒漠化, 土地利用, 土地管理, 榆林市

Abstract:

Soil organic carbon (SoC) is considered to be a key index in evaluation of soil quality, soil degradation and soil C sequestration. In order to discuss the temporal-spatial dynamics of SoC in reversed desertification area, Yulin County is taken as a case. Data of SoC were obtained based on the Second National Soil Survey in 1982 and re-sampling in 2003. Methods to soil sampling, SoC determination, soil organic carbon density (SoCD) and storage (SoCS) calculation are soil auger, K2Cr3O7 oxidation and FeSO4 titration and area-weighted mean values, respectively. On average, SoCD and SoCS and their changes vary between different soil groups, soil C pools and sub-areas. During 1982 and 2003, soil organic carbon density (SoCS) for arable layer (0-20 cm), 1-m depth (0-100 cm) and whole profile (100±10 cm) increase 0.15 kgm-2, 0.29 kgm-2 and 0.31 kgm-2 respectively, being equal to increments of SoCS of 10.12 Gg, 19.06 Gg and 20.10 Gg, correspondingly. As for soil C pools, arable layer is much more sensitive to climate change, land use/management and other human activities than 1-m depth and whole profile. With regard to soil group and sub-area, the change of SoCD of sandy soil distributed in the northwest is much less than that of loessal soil distributed in the southeast, thus per unit area SoCS in the northwest is lower than the southeast. As far as soil genus, the SoCD of moving sandy soil and semi-fixed sandy soil is significantly lower than that fixed sandy soil, and sandy loamy loessal soil is less than light loamy loessal soil, which indicate that there is great potential to increase SoC in the study area. These data demonstrate that afforestation, agroforestry, tillage of soil and water conservation, and other soil restoration countermeasures can enhance soil C sequestration and mitigate the atmospheric concentration of CO2.

Key words: soil organic carbon (SoC), land desertification, land use, land management, Yulin County