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现代地质 ›› 2012, Vol. 26 ›› Issue (5): 896-909.

• 地球化学 • 上一篇    下一篇

青海省土壤有机碳储量估算及其源汇因素分析

 钟聪, 杨忠芳, 夏学齐, 侯青叶, 姜伟   

  1. 中国地质大学 地球科学与资源学院,北京100083
  • 收稿日期:2012-05-03 修回日期:2012-07-30 出版日期:2012-10-19 发布日期:2012-10-23
  • 作者简介:钟聪,女,博士研究生,1987年出生,地球化学专业,主要从事环境地球化学与生态地球化学研究工作。 Email:z10206201@126.com。
  • 基金资助:

    中国地质调查局项目“中国典型地区土壤碳汇源转化机理研究”(1212011087125);国土资源部行业基金项目“中国主要农耕区土壤碳库与固碳潜力研究”(200911020)。

Estimation of Soil Organic Carbon Storage and Analysis of Soil Carbon Source/Sink Factors in Qinghai Province

 ZHONG  Cong, YANG  Zhong-Fang, JIA  Hua-Ji, HOU  Jing-Xie, JIANG  Wei   

  1. School of Earth Sciences and Resources,China University of Geosciences,Beijing100083,China
  • Received:2012-05-03 Revised:2012-07-30 Online:2012-10-19 Published:2012-10-23

摘要:

收集了青海省第二次土壤普查资料的2 856个土壤统计剖面数据,计算了20世纪80年代青海省土壤0~20 cm和0~65 cm深度的土壤有机碳密度,根据1∶400万数字化土壤类型图,统计了不同类型土壤的土壤有机碳储量。结合本研究采集的105个表层土壤数据,估算了青海省典型地区土壤有机碳近30年来的年均变化量。研究建立了土壤有机碳含量与温度、降雨等气候因子的关系方程,根据青海省土地利用现状估算了不同时期土地利用方式变化对青海省土壤碳源汇转化的影响。结果显示:(1) 0~20 cm表土层SOCD20加权平均值为4.509 kg/m2,其值在各类型土壤间差异较为显著,SOCR20为2.953 Pg;0~65 cm的SOCD65加权平均值为13.597 kg/m2,SOCR65为8904 Pg。由于受气候、土壤类型、植被类型、海拔等因素的影响,青海省土壤有机碳密度的分布呈现自东南向西北递减的带状分布特征;(2)近30年来青海省有机碳含量明显下降;(3)根据气象站的资料,分析了近50年来的年均气温变化趋势,预测在全球变暖背景下青藏高原土壤将表现出碳源效应,而研究区愈加明显的人类活动影响、大面积草地退化等土地利用方式改变也是造成土壤碳释放的主要原因之一。

关键词: 土壤有机碳密度, 土壤有机碳储量, 空间分布, 全球变暖, 碳源汇转化, 青海省

Abstract:

In this paper, the soil organic carbon density of the topsoil (0-20 cm) and the 0-65 cm soil is calculated according to the data from 2,856 soil profiles which are obtained from the second soil survey of Qinghai Province. Organic carbon reserves of different soil are estimated according to the 1∶4 million digitized soil map. Dominating factor of carbon source/sink is analyzed based on the relationship between organic matter, climate, and the data of changing in land use type in different periods. Results showed opinions as follows. (1) The average weight of SOCD20 of the topsoil (0-20 cm) is 4.509 kg/m2; however, there is a significant distinction in different types of soil, with SOCR20 2.953 Pg. The average weight of SOCD65 of the soil profile is 13.597 kg/ m2, with SOCR65 8904 Pg. Generally, as it is limited by the climate, the soil types, the vegetation types and the altitude, the SOCD in Qinghai Province appears a zonal distribution which decreases  from southeast to northwest.(2)Organic carbon content of Qinghai Province declined significantly in recent 30 years. (3) Our study predicted the carbon source in Qinghai Tibet Plateau under the influence of global change, according to the tend analysis of mean annual temperature in recent 50 years, which is of great importance to the global change. With the anthropogenic factors, the release of soil carbon because of the transformation of land use types, such as changing grassland to arable soil, is also a main carbon source in the study area.

Key words: soil organic carbon density;soil organic carbon storage;spatial distribution;global warming;carbon source/sink, Qinghai Province