Mapping the Land Suitability for Paddy, Corn, and Soybean in Tropical Situation of Jombang District, Indonesia

Abstract

The characterization and introduction of agroecology is separated into several zones based on the physical conditions of the environment. This study aimed to obtain land suitability for paddy, corn, and soybean-based information and potential of the local resource, which is a digital map of agroecological zones (AEZs) and crop requirements in Jombang district. The strategy is that land suitability zones for rice, corn, and soybeans can be extrapolated to other areas that have the similar agroecology zones in the Jombang region or other regions in Indonesia. This research includes the following 3 series of activities: (1) data gathering and administration, (2) field activities, and (3) data processing. Information on climate characteristics, plant growth, and needs were obtained from field studies and literature studies and then the information was overlaid using a land use expert system with the ALES (automated land evaluation system) program to determine the ZAE class. The results of this study were that AEZ in Jombang district is dominated by Zone IV with a slope of <8% (66.69%), consisting of paddy, corn, soybeans, and sugarcane commodities. Zone III with a slope of 8–15% (1.77%) consists of mango, banana, and corn commodities. Zone II with a slope of 15–30% (3.38%) consists of durian and mango commodities. The zone above (30–40% slope) is an area with natural vegetation (4.79%). Suitable land (S1) for rice is 37,062 Ha (33.09%) and for corn is 14,698 Ha (13.12%), and quite suitable land (S2) for soyabean, is divided into S2nr (nutrient retention), an area of 10.99%, and S2rc, nr (root media and nutrient retention), and an area of 18.33%. Land suitability class determines the level of land management and technology required to obtain optimal crop yields. Land suitability for paddy, corn, and soybeans based on ZAE in Jombang District can be extrapolated to other areas that have similarities.