Comprehensive evaluation of fertility quality in hilly tea plantation soils based on GIS and geostatistics Spatial variability of soil organic carbon and available phosphorus in a typical Karst depression, northwest of Guangxi Spatial heterogeneity of soil salinity in oasis at catchment scale Spatial distribution characteristic and its influential factors of soil nitrogen in Chengdu Plain Spatial variability of soil nutrients in wetland of Liangzi Lake Quantification of Suitability Distribution Region of Bursaphelenchus xylophilus in China