A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Water Engineering and Management, School of Engineering and Technology

Thesis (M. Eng.) - Asian Institute of Technology, 2023

Ecosystem services and their interactions can vary due to LULC, and these alterations can impact both the sustainable provision of ecosystem services and welfare of human. It is critical to comprehensively understand the spatial temporal dynamics of ecosystem services and interactions among them, such as positive or negative correlations for sustainable ecosystem management through decision-making, policy development, and regional landscape strategies. Taking the Pasak river basin as a research area, this study sought to propose an integrated framework coupling Terrset (Land Change Modeler) and InVEST ecosystem service model for identifying the influences of land cover and land utilization practices alteration on the tradeoffs and synergies between hydrological ecosystem services (HESs). The coupled models are used to analyze spatiotemporal variations of land cover and land practices in the region and evaluate their impacts on the interactions of three vital HESs (annual water yield, sediment retention service, and flood mitigation service) during 2000-2020 and under different land use scenarios in 2040. Terrset (Land Change Modeler) is applied to predict the land use scenarios of business as usual, agricultural expansion and conservation of forests for the period of 2040, and the characteristics of HESs under these scenarios are explored by the application of InVEST. Thereafter, a Pearson correlation assessment is performed to analyze the synergies and trade-offs among different HESs. The results demonstrated that there was a substantial shift in land coverage situations in Pasak river basin throughout the study period. While forests and field crops land have consistently diminished, urbanization has expanded along with the inclination of perennial crop and miscellaneous area. This study{u2019}s findings demonstrate an overall decline in services in the watershed due to land use change, and variation in interrelation between pair of these HESs under different management scenarios. The findings of this study highlight the need to take ecosystem service trade-offs and synergies into account in integrated spatial planning to ensure the sustainability of future ecosystem services.