黄土丘陵区县域农田土壤近30年有机碳变化及影响因素研究:以甘肃庄浪县为例  

Changes and Influencing Factors of the Soil Organic Carbon in Farmland in the Last 30 Years on Hilly Loess Plateau: A Case Study in Zhuanglang County, Gansu Province

作　　者：师晨迪[1] 许明祥[1,2] 邱宇洁[1] 张志霞[2] 张晓伟[3] 

机构地区：[1]西北农林科技大学林学院,杨凌712100 [2]中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,杨凌712100 [3]西北农林科技大学资源与环境学院,杨凌712100

出　　处：《环境科学》2014年第3期1098-1104,共7页Environmental Science

基　　金：中国科学院战略性先导科技专项(XDA05050504);中国科学院知识创新工程重要方向项目(KZCX2-YW-443);国家自然科学基金项目(41171422)

摘　　要：通过采样分析，结合20世纪80年代全国第二次土壤普查土壤有机碳数据，对庄浪县农田耕层（0-20cm）土壤近30年有机碳变化及影响因素进行研究．结果表明：①全国第二次土壤普查时土壤平均有机碳含量为6．80g·kg^-1，2011年为8．90g·kg^-1．近30年有机碳含量增加了30．9％，表现为碳汇效应．有机碳含量增加的农田面积约占庄浪县耕地总面积的90％．②在现有管理措施和农田投入下，黄绵土有机碳的稳定水平约为11．0g·kg^-1．有机碳积累量呈现出离稳定值越远变化越大、离稳定值越近变化越小的规律．③近30年土壤有机碳含量变化受海拔高度、初始有机碳含量和土壤类型等因素的显著影响，其中海拔高度对有机碳变化的影响程度最大，初始有机碳含量、土壤类型、产量及有机肥用量对土壤有机碳变化的影响次之，坡向对有机碳变化的影响最小．By analyzing the sampled data and the results of the second national soil survey by the mid 80 s in Zhuanglang County, the article studied on the changes and influencing factors of the soil organic carbon in farmland of this area in the last 30 years. Farmland samples of top soil （0-20 cm） were collected and analyzed in July 2011. The results showed that ① The average contents of the soil organic carbon in the county＇s farmlands were 6.80 g＇kg-l in 1985 and 8.90 g.kg^-l in 2011. It increased by 30.9% in the past 30 years, which appeared as a carbon sink effect. The area of increasing contents of soil organic carbon accounted for about 90% of the county＇s farmland area. ② Under the available management measures and farmland input, the loessal soil organic carbon stability level was 11.0 g.kg^-1 , The SOC accumulation rate showed that the farther the SOC was from the stability level the more quickly it changed, and the closer the SOC was from the stability level the slower it changed. ③ The SOC changes was affected by the altitude, the primary content of organic carbon, and the soil types and so on, in which the greatest contribution factor was the altitude, the influence of the primary content of organic carbon, soil type, production and organic fertilizer on soil organic carbon change was smaller, and the slope aspect had the smallest effect on soil organic carbon change.

关 键 词：土壤有机碳 有机碳变化 影响因素 县域 黄土丘陵区 

分 类 号：X144[环境科学与工程—环境科学]