Analyzing future land cover change in Chiang Mai-Lamphun basin using GIS and multi-scenarios modeling

Abstract

Changes in land cover in the Chiang Mai-Lamphun basin have been influenced by the pressure of rapid socio-economic developments. Increase of building residential areas and farming areas influenced by local socio-economic factors has resulted in declining the forest covers and may have negative impacts on ecosystems. This thesis aims to understand the mechanism of land cover change in the past, the present, and the future that can be used as supplemental data for environmental planning and conservation. In this study, manifold geographic information system techniques were utilized for data extraction, management, and analysis. In 2021, Markov-cellular automata (Markov-CA) and a multi-layer perceptron (MLP) were employed to model land cover changes using four scenarios. Then, the future land cover maps for 2030 and 2050 were developed based on the 2021 transition probability metrics. The different scenarios were based on socio-economic schemes, which included the business-as-usual scenario (BaU), the ecological protection scenario (EPS), the pessimistic development scenario (PDS), and the baseline development scenario (BDS). As a result of model validation using 534 ground survey points in 2021, the BaU in 2021 generated the highest overall accuracy (82.77%) with a Kappa value of 0.7846, quantity disagreement value of 0.0693, and allocation disagreement value of 0.1030. While the accuracy in PDS and BDS were comparatively low compared to BaU and EPS. The simulated 2021 BaU scenario reflected the current trends of socio-economic development. It was proposed that the projected BaU in 2050 revealed the decrease of forest land, whereas 6.04% and 1.59% of forests were converted to agricultural areas and built-up areas, respectively. At the same time, the increase of the built-up areas dominated 6.04% of the existing agricultural areas in 2021. These scientific trends were used to gather local perceptions on the described socio-economic settings. Implications for possible land use management in the Chiang Mai-Lamphun basin were discussed.