Mapping of the soil phosporus using landform approach on apple orchard in Batu, East Java']Java Province, Indonesia

Soil phosphorus (P) is an essential nutrients for plant growth. A more understanding of the spatial-variability of soil phosporus is needed to fulfill best management of P in precision farming. The mapping method of soil phosphorus variability that is widely used so far is the interpolation method. However, this method works well only if the number of samples involved is high and the distance between the sample points is tight. In consequence, it takes a lot of time, effort, and cost, which become an obstacle in the application of the precision farming concept. The aim of research was to analyze the potential usage of landforms as a basis for mapping the soil total P content in apple orchard. The study area was located on apple orchard Batu, East Java Province, Indonesia. The soil attribute was analyzed by HCl 25% ekstract method. Delineation of landforms was used ArcGIS 10.1 software. Stratified random sampling based on landform was the method that used to determine of sample point, at 0 to 0.5 m depth. The apple orchard is classified into nine zone with soil total phosporus contents of soil varying from low to very high. The soil was submitted to inferential statistical by GLM Univariate 5% method with SPSS 16.0 software. The significant value (Sig.) of GLM Univariate 5% was less than 0.05. It means that the soil total P content in various zones are significantly different. It also shows that the landform influences the spatial variability of soil total P content. Therefore, the landform can be used as a efficiency basis for mapping the soil total P content of the apple plantation.