Spatio-temporal changes of land use land cover and ecosystem service values in coastal Bangladesh

Abstract

Increased human activity and dynamic climate variables have radically altered the global land use land cover (LULC) pattern and the ecosystem services (ES) they offer. However, assessing the impact of such LULC dynamics on ecological resources has rarely been attempted, especially in Bangladesh. Here, we assessed the dynamics of LULC change and associated ecosystem service values (ESVs) of coastal Bangladesh during 1999–2019 by analyzing historical Landsat LULC images and economic valuation techniques, respectively. Findings revealed a high prevalence of rural settlement-based Tree Outside Forest (TOF) land sprawl over agricultural land. Besides, LULC transition analysis revealed an increase in built-up, mangrove forest, water bodies, and saltpan/aquaculture areas and a decrease in agricultural and bare land areas. Overall, the ESV of coastal Bangladesh decreased by 0.47 billion US dollars, from US$ 25.18 billion in 1999 to US$ 24.71 billion in 2019. However, the values of different ES functions, such as food (−10.7%) and raw materials (−7.7%), were found most affected, while slight progress was evident in biodiversity protection (+2.2%), and water regulation (+1.1%) functions. Strong spatial dynamics of ESV changes were observed, with the largest decreases in the districts of Satkhira (−7.90%), Cox'sbazar (−5.75%), and Noakhali (−4.61%), and the highest increases in the districts of Lakshmipur (+4.65%) and Patuakhali (+3.18%). The findings regarding mangrove and TOF growth have important implications for building a buffer against ESV degradation due to the substantial decline in agricultural lands in other parts of the world with related socio-geographical and environmental problems.