Pengembangan metodologi identifikasi dan evaluasi potensi sumberdaya lahan dengan mengintegrasikan basis data tanah, citra satelit, dan model elevasi digital

Abstract

Land resources mapping aimed to provide spatial data and information of land resources. Data and information provision is used to assess the potential of land resources for agriculture. In the current implementation, these activities require considerable time and cost. Regarding to the above case, mapping methodology on land resources potential that much faster, less cost and accurate in accordance with mapping scale should be developed.Utilization of soil databases, satellite imagery, and DEMs is an alternative to the development of methods and mapping techniques. The objectives of this study are: (1) to find out the relationship between soil characteristics and parent material, relief , climate from soil database resulted from earlier land resources mapping to generate mapping units, (2) to find out the benefits of satellite imagery and DEMs on identifying and delineating mapping unit attributes, particularly relief and lithology/parent material, and (3) to develop and to define the methodology of land resources potential identification and evaluation based on the relationship between the soil-forming factors and soil characteristics as land unit by integrating soil data base, remote sensing images the so called satellite and digital elevation models (DEMs) using GIS (InBIG) . The research has performed 2 (two) phases of study. Phase I performed the study of soil data base to find out the relationships between soil-forming factors and soil characteristics which have been established through correspondence and diversity analyses. Phase II performed a research on methodology development and preparation of land resource potential mapping by analyzing and delineating the attributes of mapping unit (parent material, climate, and relief) by integration of (1) Digital Elevation Models (DEMs), (2) satellite imagery , (3) geological map, (4) precipitation data, and (5) contour maps using GIS techniques. The results showed that the parent material was a factor that determine the soil characteristics. Parent material influenced soil texture and pH; climate and relief affected Cation Exchangeable Capacity (CEC) and the soil reaction (pH). The relationship is then used to define Characteristics Unit of Agricultural Land Carrying Capacity (SKDLP). Delineations of lithology/parent material based on geological maps that were corrected by DEMs and relatively high quality of pansharpened Avnir-2 Alos imagery was verified by ground truthing. Distribution of relief that was generated from SRTM DEMs with 30 m resolution is relatively high quality in rolling to mountainous area (slope >8%), while in relatively flat area (slope <8%) needs to be controlled by contour maps and pansharpened Avnir-2 Alos imagery to improve the accuracy. Climatic factor is approached by rainfall, dry month (<100 mm) and elevation. SKDLP delineation is based on spatial data of parent material, relief, and climate, while the characteristics of the soil are obtained from the soil database analyses, ground truthing, and laboratory analysis. SKDLP can be used for interpreting land resources potential and the development of agricultural commodities. SKDLP is data and information of land resources potential in semi-detailed scale (1:50,000) that use advanced technology by integrating satellite imagery, DEMs data, and GIS techniques as well as soil data based to speed up the mapping of land resources potential that more efective and efficient. If InBIG method is applied then it will have time efficiency of 54.17 percent and 70.53 percent cost efficiency in comparison to the conventional method.