摘要
为准确评价土壤有机碳的尺度效应,分析其多尺度的变异特征并找到控制土壤有机碳空间分布的主导因素,选取内蒙古赤峰市敖汉旗为研究区,以实地调查数据为基础,对研究区进行多尺度采样,采用经典统计学与地统计学相结合的方式分析敖汉旗表层(0～20 cm深度)土壤有机碳空间变异的尺度效应。结果表明:县域、中等区域和小流域尺度上表层土壤有机碳平均质量分数分别为7. 49,7. 57和7. 54 g/kg。3种研究尺度上土壤有机碳均具有中等强度的空间相关性,变程在980～2 100 m之间,随着研究尺度的缩小,土壤有机碳的空间自相关距离逐渐缩小。不同研究尺度上各影响因子与土壤有机碳质量分数的相关关系存在较大差异,县域尺度上土壤和植被因子对土壤有机碳质量分数的影响最大,中等区域尺度上植被和海拔因子对土壤有机碳质量分数的影响最大,小流域尺度上海拔和坡度对土壤有机碳质量分数的影响最大。
[Background] Soil carbon pool is the largest carbon pool in terrestrial ecosystem,and its dynamic change and the distribution of reserve play an important role in the quality of soil. Therefore,the accurate estimation of soil organic carbon（ SOC） storage, analysis of the spatial variability and uncovering the main factors that control the spatial distribution of SOC may provide basic data and theoretical basis for regional ecological construction and scientific and rational use of land resources.[Methods]This research was conducted in Aohan banner of Chifeng city,Inner Mongolia,based on soil survey data. The scale effects of spatial variability in surface SOC（ 0-20 cm soil depth） was studied by multi-scale sampling of small watershed,medium region and county scale. The classical statistics and geostatistics with software GS ＋ 7. 0 ArcGIS10. 0 were used to analyze the spatial variability of surface SOC content. [Results] 1） The mean contents of SOC at the county,medium region and watershed scales were 7. 49,7. 57 and 7. 54 g/kg,respectively. The change range of organic carbon content in the3 scales was found to be between 1. 43-19. 48,1. 31-19. 89,and 1. 23-19. 95 g/kg,respectively.There was no significant difference in the surface soil organic carbon fractions between the 3 scales,all of which were at a relatively low level. SOC contents showed a moderate spatial correlation with the range between 980 m and 2 100 m at the 3 scales. 2） The Gauss model had better fitting effect on the soil organic carbon fraction of the small watershed scale,and the spherical model had better effect on the soil organic carbon content in the county and middle scale. The model fitting residuals was relatively small（ 1. 96-2. 43）,and the determination coefficient was between 0. 50-0. 75,which showed that the selected model described the spatial structure characteristics of soil organic carbon content on each scale more accurately. The C0/（ C0＋ C） reflected the variation characteristics of soil organic carbon da
作者
李龙
姜丽娜
白建华
LI Long;JIANG Lina;BAI Jianhua(School of Deseit Control Science and Engineering,Inner Mongolia Agricuhural University,010018,Hohhot,China;Research Institute of Forestry New Technology,Chinese Academy of Forestry,100091,Beijing,China)
出处
《中国水土保持科学》
CSCD
北大核心
2018年第5期40-48,共9页
Science of Soil and Water Conservation
基金
中央级公益性科研院所基本科研业务费专项资金(CAFYBB2016SY038)
关键词
尺度效应
土壤有机碳
空间变异
地统计学
半干旱区
scale effect
soil organic carbon
spatial variability
geostatistics
semiarid zone
