Study of Land Spatial Characteristics of Bluto Sub-district, a Center Production of Cabe Jamu (Piper retrofractum Vahl.) Production, Using Geographic Information Systems (GIS)

Abstract

The yield of a plant is strongly influenced by land characteristics and cultivation techniques. Geographic Information System (GIS) can be applied for land management and decision-making based on site-specific regarding soil fertility precisely. The purpose of this study was to investigate land characteristics, especially soil-chemical properties of Bluto District area, a region center for Cabe Jamu (Piper retrofractum Vahl.) production, by means of Geographic Information System (GIS). The research was carried out in Bluto District, Sumenep, from September to December 2022. A soil map unit (SPT) of Bluto District was produced by overlaying the topographic map of Indonesia (RBI), slope maps (resulting from SRTM Digital Elevation Model (DEM) data processing), and geological maps.Field work to collect topsoil samples from each “SPT” using a diagonal system. The soil samples were analyzed for texture (pipette method), soil pH (electrical method), organic C content (Walkey-Black Method), total N (Kjeldahl Method), available P (Olsen Method), exchangeable cations (ex-K, ex-dd, ex-Ca, and ex-Mg) and CEC (N NH4OAc pH 7.0). Data were employed for establishing a map of land characteristics and analyzed by using the Inverse Distance Weighting (IDW) interpolation method. The results of the spatial analysis of land characteristics provide a complete picture as a reference for area-based management. The results of the analysis show that the texture is generally sandy loam and loam, the actual pH is slightly alkaline, the potential pH is neutral and slightly alkaline, total N is classified as low to medium, P-availability is very high, C-organic is generally classified as medium and high, CEC is dominated by medium criteria, Ca-dd throughout the region is very high, Mg-dd is medium and high, Na-dd is very low and low, and K-dd is dominated by high criteria.