华中丘陵红壤物理性质空间变异性的研究

Spatial variability of saturated hydraulic conductivity, clay and physical clay particles, water-stable aggregate and porosity of red soil were studied using a geostatistical method. Field experiments were undertaken on a red soil at Yingtan, Jiangxi Province, China. There were thirty sampling locations in the experimental field with an area of 50×100 m. The autocorrelation distances of various physical parameters determined in field were different according to the analysis of semivariogram and autocorrelogram: saturated bydraulic conductivity of soil 42.0 m, clay 43.5 m, physical clay 56.0 m, macroaggregate 47.0 m, total porosity 65.0 m, porosity in diameter of>0.03 mm 37.5 m and clay in layer B (20—30 cm) 45.0 m. The estimation of seven soil parameters by using Kriging interpolation method shows that Kriging method was obviousty better than Jackkniffing technology. Its estimated error was just 67.5—90.5% of 3ackniffings'. The saturated hydraulic conductivity of soil was estimated bv porosity in diameter of>0.01 mm and the clay content in B layer was estiamted by clay content in A layer in terms of Cokringing technology. Its estimated error was only 54.1—65.5% of that of linear regression method and 36.2—86% of Kriging's respectively.