[Spatial variability of soil nutirients and their relations with rice yield at village scale in karst mountainous area of Guizhou Province, Southwest China].

By using geo-statistics methods, an investigation was conducted on the spatial variability of soil pH, organic matter, total N, P, and K, and available N, P, K, Cu, Zn, Fe, and Mn and their relations with rice yield in Wenxing Village, Anshun City of Guizhou Province, Southwest China. The C0/(C0 + C) ratios for the soil pH, total P, and available N, P, K, and Cu and the rice yield components were lower than 25%, indicating their strong spatial correlations, while the C0/ (C0 + C) ratios for the soil organic matter, total N and K, and available Zn, Fe, and Mn and the rice yield were 25%-75%, showing a medium spatial correlation. Of all the soil nutrients, the soil available K had the closest relation with rice yield (r = 0.4669, P < 0.0001). The direct path coefficients of the soil available N, K and P to the effective panicle and thousand-grain mass were positive, in line with the partial correlation analysis. The Kriging interpolation showed that the soil organic matter, total N, and available N, K, Cu, and Zn contents presented a decreasing trend from the southwest to northeast, but the rice yield was higher in the northwest and southeast of the Wenxing Village.