Concentrations of some macro and micro plant nutrient of cultivated soils in Central and Eastern Blacksea Region and their mapping by inverse distance weighted (IDW) method

The aim of this study was to determine plant nutrients content and to in terms of soil variables their soil database and generate maps of their distribution on agricultural land in Central and Eastern Black Sea Region using geographical information system (GIS). In this research, total 3400 soil samples (0-20 cm depth) were taken at 2.5 x 2.5 km grid points representing agricultural soils. Total nitrogen, extractable calcium, magnesium, sodium, boron, iron, copper, zinc and manganese contents were analysed in collected soil samples. Analysis results of these samples were classified and evaluated for deficiency, sufficiency or excess with respect to plant nutrients. Afterwards, in terms of GIS, a soil database and maps for current status of the study area were created by using inverse distance weighted (IDW) interpolation method. According to this research results, it was determined sufficient plant nutrient elements in terms of total nitrogen, extractable iron, copper and manganese in arable soils of Central and Eastern Blacksea Region while, extractable calcium, magnesium, sodium were found good and moderate level in 66.88%, 81.44% and 64.56% of total soil samples, respectively. In addition, insufficient boron and zinc concentration were found in 34.35% and 51.36% of soil samples, respectively