Demarcation of Suitable Land for Rice Cultivation Using GIS-based Multi-Criteria Decision Analysis: A Case Study in Southern Highlands Province of Papua New Guinea

Papua New Guinea (PNG) has abundant land resources that are not fully utilized. Rice is a key food staple in urban areas and some rural regions. The demand for rice products remains high in Papua New Guinea due to changes in dietary preferences. Despite substantial consumption levels, rice is the principal imported crop grain, addressing the needs of a rapidly growing population. Maximizing the potential of land resources is crucial for properly assessing and categorizing land for specific purposes. This research project aims to address this pressing concern through land suitability analysis. An approach incorporating a multi-criteria decision analysis (MCDA) was employed to define and evaluate land suitability for rice cultivation. This research was conducted in the Southern Highlands Province, which is prominently located in the center of mainland Papua New Guinea (PNG). Fourteen parameters, including soil depth, texture, drainage, nitrogen, phosphorus, potassium, pH, cation exchange capacity, topographic wetness index, land use and land cover, altitude, slope, aspect, rainfall, and temperature, were selected and analyzed further through Pairwise Comparison to derive weights and ranks. The resulting output from the MCDA was categorized into five distinct classes: unsuitable land with extreme limitations, unsuitable land with severe limitations, suitable land with moderate limitations, suitable land with minor limitations, and appropriate land with negligible limitations. According to the findings, approximately 29.59% of the study area is ideal for rice cultivation. Although applied exclusively to the rice crop, this technique holds potential for adaptation to various crops.