Analysis of The Quality of The Mamasa Sub-Watershed Using The Land Cover Approach and Land Cover Projections in 2031

Abstract

The biophysical cover that can be seen on the earth’s surface due to regulation, activity, and human intervention is called land cover. In general, changes in land cover can be observed using spatial data from land cover maps from several points in different years. Changes in land cover in a watershed will directly affect the quality of the watershed. This study aims to analyze land cover changes in 2011 – 2016 and 2016 – 2021, analyze land cover change projections in 2031, and analyze watershed quality using the Percentage of Vegetation Cover approach. The overlay analysis approach was used to conduct an examination of land cover change. Land cover change projections were carried out using the Multi-Layer Perceptron method and Cellular Automata (CA) Markov chain modeling in Idrisi TerraSet Software and watershed quality analysis by calculating the PPV entering the plants permanently. The results of this study note that changes in land cover in 2011 – 2016 experienced a change of 763,53 hectares, and in 2016 – 2021, the most significant change was 802,69 hectares. The biggest change in land cover occurred in the closure of dry land agriculture. The results of the projected land cover in 2031 have changed by 4.472,44 hectares, with the most significant change occurring in dry-land agriculture. Calculating the percentage value of vegetation cover shows that the quality of the Mamasa sub-watershed has decreased from very good to sound due to a decrease in permanent vegetation.