关键词: 盐化灌淤土, 空间变异, 半方差函数, 盐分, 棉花

Abstract: The study researched relationship between the spatial variability of soil solute salt and cotton growth of saline anthropogenic-alluvial soil by the methods of traditional statistics and geostatistics. The results of traditional statistics analysis showed：the data of soil solute salt accorded with normal probability distribution, and the reasonable sampling numbers were 27 in the cotton field under the certain precision and credible level. The results of sem-i variogram analysis showed：at the horizontal direction, the spatial variability of soil solute salt of the surface layer was moderate, the coefficient of variation of soil solute salt before sowing was 25.14%; the coefficient of variation of soil solute salt at 20～40 cm and 40～60 cm layer was respectively 43.18% and 43.44% before sowing; the coefficient of variation of soil solute salt at 0～20 cm, 20～40 cm layer was respectively 271% and 37. 7% for the period of cotton boll. These data showed：the solute salt of soil had no clearly vertical variability, the results greatly relative to characters of parent material. The spatial variability of the soil solute salt was decreased with the growth of cotton, and their sem-i variogram maps and contour maps were presented, the results had a connection with some man-made factors, such as cultivation, planting, irrigation, and so on. With influence upon the man-made factors, soil solute salt had short-time season change and long-time annual change, the short-time spatial variability of soil solute salt was very obvious, the spatial distribution was influenced greatly by structural factors, such as soil type, parent material, climate, topography and so on. In sampling of field, in order to improve sampling effectiveness and experimental precision, the range and the contour map could be used to design economic and reasonable sampling plan and determine the point place of salt dynamic observation. The relative analysis of soil solute salt and cotton yield showed：they had outstanding negative correlation, and the negative correlation came up to notable or greatly outstanding standards, that showed the soil solute salt was one of important limited factors of cotton yield. The study provided the basic data and theoretical basis for improving the saline soil and increasing experimental effectiveness.

Key words: Saline anthropogenic-alluvial soil, Spatial Variability, Sem-ivariogram, Salt, Cotton