几种不同方法估算农田表层土壤固碳潜力:以甘肃庄浪县为例  

Estimation of Topsoil Carbon Sequestration Potential of Cropland Through Different Methods: A Case Study in Zhuanglang County,Gansu Province

作　　者：师晨迪[1] 许明祥[1,2] 邱宇洁[1] 

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

出　　处：《环境科学》2016年第3期1098-1105,共8页Environmental Science

基　　金：科技基础性工作专项(2014FY210100);中国科学院战略性先导科技专项(XDA05050504);国家自然科学基金项目(41171422)

摘　　要：通过采样分析,结合80年代全国第二次土壤普查以及2006年耕地质量评价土壤有机碳数据,采用几种不同的估算方法对庄浪县农田表层(0~20cm)土壤固碳潜力进行了估算.结果表明:1最大值法和分类定级法(高)对同一地区农田土壤理想固碳潜力估算结果差异不大.最大值法估算庄浪县农田表层土壤理想固碳潜力为1.13 Mt,而分类定级法(高)估算的理想固碳潜力为1.09 Mt.2分类定级法(中)、饱和值法、加权法这3种固碳潜力估算方法求得庄浪县农田土壤现实固碳潜力分别为0.37、0.32、0.28 Mt,约为理想固碳潜力水平的1/3.3采用分类定级法(中)、饱和值法和加权法估算现实固碳潜力,有机碳密度增量依次为6.76、5.21、4.56 t·hm^(-2).按照庄浪县近30年农田表层(0~20 cm)土壤的固碳速率,达到现实固碳潜力水平大约需要24~34 a.4在县域尺度上估算现实固碳潜力,加权法优于饱和值法,饱和值法优于分类定级法(中);估算理想固碳潜力,分类定级法(高)优于最大值法.By analyzing the sampled data and the SOC data of the second national soil survey by the mid 80 s and the national cultivated land quality evaluation in 2006 in Zhuanglang County,the article studied the cropland topsoil organic carbon sequestration potential estimation using several different methods. The results showed that： 1 There was no significant difference among different estimation methods about cropland carbon sequestration potential in the same region. Taking cropland carbon sequestration potential in Zhuanglang County for example,the theoretical values estimated by maximum value method and classification grading method were 1. 13 Mt and1. 09 Mt,respectively. 2 The real values estimated by classification grading method,saturation method,weighting method were 0. 37 Mt,0. 32 Mt,0. 28 Mt,respectively,which were about 1/3 of the theoretical value. 3 The SOC density increments to reach the real level of carbon sequestration potential estimated by classification grading method,saturation method and weighting method were 6. 76t·hm^（-2）,5. 21 t·hm^（-2）,4. 56 t·hm^（-2）respectively. According to the topsoil carbon sequestration rate of cropland in Zhuanglang county in the recent 30 a,it would need about 24-34 a to achieve the real level. 4 At the county scale,the weighted method was superior to the saturation value method,and the saturation value method was better than the classification grading method in the actual carbon sequestration potential estimation. The classification grading method was better than the maximum value method in the ideal carbon sequestration potential estimation.

关 键 词：土壤有机碳 固碳潜力 估算方法 农田土壤 加权法 

分 类 号：X144[环境科学与工程—环境科学]