Scale Characteristics of Spatial Variability of Soil Organic Matter in Complex Landscape Region A Case from Dengfeng City of Henan Province
Taking Dengfeng County as the study area, variation characteristics of the content of topsoil organic matter （SOM） was investigated for a better understanding of scale effect involved in spatial variability of soil attributes in a complex landscape. It was found that the mean SOM content and the variation coefficient in the whole study area were 20 g kg-1 and 44.8% respectively, when soil sampled under the 2 ~ 2 km grid control. In the landscape type of landscapes located in the study area, namely Purple Soil Zone, Quartz Sandstone Zone, Proluvial Fan and Diluvium Zone. Topsoil was sampled at smaller pace and under 200 200 m, 300 × 300 m, 300 × 300 m and 500 × 500 m grid control respectively, the predicted values of the SOM contents were 15.72 g kg-1, 15.53 g kg-1, 26.00 g kg-1, 18.98 g kg-1, with the corresponding variation coefficients 29.9%, 26.21%, 16.04%, 35.41%. The significant differences were found in semivariance amongst different landscapes and sampling densities. And, at the study area scale, extremely significant and significant correlation between SOM and terrain factors elevation and aspect was demonstrated, while the significant correlation between SOM and slope failed to be found. At the landscape scales, there was no significant correlation between SOM and terrain factors, except for the extremely significant correlation between SOM and elevation in the Diluvium Zone in Low Mountain or Hill of the study area.
NETL
NSTL
万方数据
维普
