摘要
应用地统计学方法,研究河套永济灌域表层土壤(0~20 cm)有机碳(TOC)和总碳(TC)的空间异质性及二者之间的相关性。结果表明,土壤TOC平均含量为6.96 g/kg,TC平均含量为21.06 g/kg,TOC占TC的33.05%,二者之间线性回归方程为:YTC=13.169xTOC+1.252(F=142.846,P<0.001)。在不同土地利用方式下,TOC含量差异非常显著(F=13.136,P<0.001),林地和农田中TOC含量显著高于荒地(P<0.05)。TOC和TC的半方差拟合结果分别为高斯模型和球型模型,空间相关度分别为16.73%和0,具有强烈的空间相关性。TOC和TC含量在空间上呈斑块状分布,以永济干渠为中心向两边对称增高。虽然土壤受到施肥、灌溉等农业管理小尺度因素的影响,造成土壤TOC在不同土地利用方式下的含量差异显著,然而却未达到破坏其原有空间格局的程度,TOC和TC的空间变异均由土壤母质、气候、地形等自然因素引起,可能与海拔、地形起伏等因素引起的太阳辐射、降水格局及植被覆盖等差异有关。
Geostatistical techniques were used to quantify the spatial heterogeneity and relationship between soil total organic carbon(TOC) and total carbon(TC) at 0-20 cm soil layer in the Yongji irrigation sub-district(YD) from the Hetao irrigation district(HD). The results showed that the mean values of TOC and TC were 6. 96 g/kg and 21. 06 g/kg,respectively. TOC accounted for about 33. 05% of TC and the linear regression equation was YTC= 13. 169 xTOC+1. 252(F =142. 846,P<0. 001). TOC significantly differed among three land-use types(F = 13. 136,P<0. 001),and the concentration in cropland and forestland significantly higher than that in wasteland(P< 0. 05). TOC and TC was mostly accordance with the gaussian and spherical models,respectively,and the values of special related degree were 16. 73% and 0,indicating that soil carbon strongly correlated in the special heterogeneity. TOC and TC distributed plaques in the YD on the space,with increasing from the Yongji Canal(YC)to both sides,symmetrically. The fertilization,irrigation and other farm management would cause difference of TOC among the different land-use types at small scale,but that did not destroy soil carbon in the original space. The special heterogeneity of TOC and TC in the YD was subjected to natural factors such as soil parent material,climate,topography and so on,which maybe have relation to the differences of solar radiation,precipitation and vegetation pattern caused by the differences of altitude,topographic relief and other natural factors.
出处
《江苏农业学报》
CSCD
北大核心
2017年第6期1294-1300,共7页
Jiangsu Journal of Agricultural Sciences
基金
江苏省农业科技自主创新基金项目[CX(16)1051]
江苏省农业科学院基本科研业务专项基金项目[ZX(17)2017]
关键词
土地利用方式
土壤有机碳
土壤总碳
空间异质性
land use type
soil total organic carbon
soil total carbon
spatial heterogeneity
