wcm.01.2026.155.162

Part of the hydrological cycle, soil infiltration serves as a pivotal indicator for evaluating water availability potential within the Kalisari Sub-watershed. By employing modeling techniques to analyze its spatial distribution, this study aims to forecast the watershed’s capacity to sustain agriculture by 2030. The research area spans approximately 5,000 hectares, encompassing five distinct land uses: P1 (mahogany-coffee agroforestry), P2 (pine-coffee agroforestry), P3 (shrub), P4 (dryland), and P5 (paddy fields). A comprehensive investigation, involving 43 observation points, was conducted to facilitate modeling and accuracy assessment through techniques such as Kappa Accuracy Assessment, implemented using QGIS 2.18 and ArcGIS 10.4. Precipitation data obtained from a rainfall simulator were utilized to simulate rainfall intensity and measure soil infiltration rates. Correlation-regression analyses were performed using R Studio, employing the Pearson correlation method to ascertain the relationship between soil parameters and infiltration. Projections indicate that by 2030, the soil infiltration rate within the Kalisari Sub-watershed is expected to be classified as “very fast” (>250 mm h-¹). Kappa accuracy modeling demonstrated an accuracy rate of approximately 82.74%, validating the reliability of the modeling approach. Furthermore, the study identified a significant interaction between land use patterns and soil properties, resulting in a dynamic decrease in infiltration rates of approximately 13.47% during 2021 to 2030 within the Kalisari Sub-watershed. However, the decrease is not significant because the lowest infiltration rate is around 328.51 cm h¹, thus indicating that the hydrological capacity of the entire watershed land is likely to remain stable under the projected land use scenario and is able to support agricultural systems until 2030.