内蒙古自治区土壤有机碳、氮蓄积量的空间特征

Spatial characteristics of soil organic carbon and nitrogen in Inner Mongolia

采用全国第二次土壤普查中内蒙古自治区的典型土种剖面资料 ,在剖面深度的基础上 ,用地统计学和地理信息系统 (GIS)方法 ,分别按土壤类型和土地覆被类型计算了土壤有机碳、氮密度 ,分析了内蒙古自治区土壤有机碳、氮蓄积量的空间分布特征 ,探讨了土壤有机碳、氮蓄积量与主要气候要素的关系 .结果表明 ,内蒙古自治区土壤有机碳密度处于 3.2 4～ 4 3.2 4kg·m-3 之间 ,土壤有机氮密度处于 2 6 9.5 6～30 85 .6 0 g·m-3 之间 ,土壤碳、氮比 (C/N)大致在 4 .4 6～ 17.13之间 .土壤有机碳、氮密度与温度呈负相关 ,相关系数分别为 0 .5 5 7和 0 .4 6 0 (n =2 4 5 ) ;与年均降水量呈正相关 ,但相关性不是很强 ,相关系数分别为0 .2 85和 0 .2 0 3.从内蒙古自治区东北地区到西南地区 ,土壤有机碳、氮蓄积量随着温度递升和降水量递减呈现降低的趋势 .

Studies on the amount and spatial distribution of soil organic carbon/nitrogen in Inner Mongolia and their relationship to main climate factors showed that the content of soil organic carbon and nitrogen was 3.24～43.24 kg·m -3 and 269.56～3085.60 g·m -3 ,respectively, and the C/N ratio was about 4.46～17.13. The correlation between soil organic carbon/nitrogen and temperature was negative, and R was 0.557 and 0.460,respectively.Soil organic carbon/nitrogen had a weak positive correlation to precipitation, and R was 0.285 and 0.203 . Soil organic carbon and nitrogen appeared a reducing trend with increasing temperature and decreasing precipitation from northeast to southwest.