Spatial Variability of Agricultural Characteristic to Evaluate Productivity Potential in Iran

摘要

Analysis and interpretation of spatial variability of soils is a keystone in site-specific farming. Grid soil sampling is typically used for establishing management zones for site-specific application of nutrients. The objectives of this study were to determine the degree of spatial variability of soil chemical properties, soil texture and variance structure. Spatial distributions for thirteen soil chemical properties and soil texture were examined in a fallow land in Bajgah district in Fars province, Iran. Soil samples were collected at approximately 60 m² at 0-30 cm depth and coordinates of each of the 100 points were recorded with GPS. The spatial distribution and spatial dependence level varied within location. The range of spatial dependence was found to vary within soil parameters. Phosphorous had the shortest range of spatial dependence (49.50 m) and percentage of calcium carbonate equivalent had the longest (181.94 m). All parameters were strongly spatially dependent. The results demonstrate that within the same field, spatial patterns may vary among several soil parameters. Soil nutrients were found to be affected by farmer management. Variography and Kriging can be useful tools for designing effective soil sampling strategies and variable rate application of inputs for use in site-specific farming.