NDVI-based Analysis of Green Space Decline and Air Quality in Dhaka: Implications for Sustainable Development Goals Abdullah Salman * , Asiqul Haque , Maksudur Rahman , Mostafa Jaman Rabby , Sabbir Hossen , Prince Halder , Raian Islam Evan Department of Geology and Mining, University of Barishal, Barishal 8254, Bangladesh *Corresponding Author Email: masalman@bu.ac.bd https://doi.org/10.18280/eesrj.100206 ABSTRACT Received: 14 March 2023 Accepted: 1 April 2023 The rapid industrialization of cities poses significant challenges to sustainable development, particularly environmental degradation. The Sustainable Development Goals (SDGs) recognize the urgent need to address this issue in industrialized regions. A case study approach obtained valuable insights into Dhaka's green spaces and their implications for SDG 11 and 15. This study explores the decrease in green cover in Dhaka City attributed to unplanned industrialization and examines its relationship with the degradation of air quality during the period spanning from 1991 to 2021. The image classification procedure yielded overall accuracy rates ranging from 0.82 to 0.90. The findings reveal a significant decline of 16% in healthy vegetation and 8.98% in shrubs/grasslands, possibly due to a 34.7% increase in built-up/bare lands. AQI increased from 124 in 1996 to 172 in 2018 in Dhaka but decreased to 163 in 2021, probably due to the COVID-19 pandemic. Unplanned industrialization has led to reduced green cover and increased air pollution in the city. The study emphasizes the utility of NDVI (Normalized Difference Vegetation Index) measurements to address these challenges and achieve the SDGs. These measurements provide valuable information for decision-making and policy formulation, promoting the creation of green environments. Keywords: Dhaka, air pollution, green space, industrialization, urbanization, NDVI, Sustainable Development Goals (SDGs) 1. INTRODUCTION The migration of individuals from rural to urban areas, commonly referred to as urbanization, has been a widespread occurrence on a global scale for decades. This process has resulted in a number of negative effects, including the loss of urban green space and an increase in air pollution [1-3], as well as a number of positive effects. Urban inhabitants can reap various advantages from green spaces, such as parks, gardens, and forests, encompassing better air quality, reduced heat island effects, and augmented mental health and well-being [4]. Trees serve as a carbon sequestration mechanism by intercepting particulate matter and microscopic pollutants, thereby enhancing the deleterious impacts of climate change. The expansion of cities often results in the relinquishment of green spaces to accommodate new constructions and infrastructure, consequently causing a decrease in the standard of living for inhabitants of urban areas. The global urban region experienced a significant increase of 168% from 2001 to 2018, with the most notable growth rates observed in Asia and Africa [5]. The inhalation of air pollution has been linked to various health issues, such as respiratory and cardiovascular ailments, lung cancer, and stroke [6, 7]. In 2019, a thorough evaluation of the worldwide burden of diseases revealed that air pollution, originating from indoor and outdoor sources, constituted the fourth most significant risk factor for mortality and disease globally. This factor was responsible for 6.67 million deaths. Air pollution accounted for 12% of fatalities in children under 5 [8]. Outdoor air pollution is responsible for causing approximately 4.2 million untimely fatalities globally each year, with the most significant impact observed in countries with low- and middle-income economies [1, 4]. Bangladesh has been categorized as a lower-middle-income nation since 2015 and is one of the nations with the highest population density globally, with a populace exceeding 160 million individuals [9, 10]. In recent years, the nation has undergone a swift urbanization process, whereby the proportion of individuals residing in urban areas has increased from 17% in 1974 to 36% in 2018 [11]. This has resulted in the expansion of cities and villages, resulting in a decrease in green spaces. The Bangladesh Bureau of Statistics conducted a study that revealed that the country's forest cover decreased from 17% in 1975 to 10% in 2010 [12]. The depletion of green areas has had a noteworthy effect on both the ecosystem and the well-being of the populace, with the issue of air pollution emerging as a significant apprehension in urban areas [13, 14]. The city of Dhaka, located in Bangladesh, is widely recognized as a highly urbanized and heavily polluted city characterized by elevated levels of environmental pollution and a notable scarcity of green spaces [5]. Over the past two decades, Dhaka has undergone a warming trend of approximately 3 degrees Celsius, which can be attributed to various factors such as the depletion of green spaces and swift urbanization. This is noteworthy as the global community aims to limit the increase in global temperature to below 1.5 degrees Celsius [15]. UNEP has mandated that a sustainable urban area should possess a minimum of 25% open space, whereas Dhaka only possesses 8% of such spaces [16]. Urban green infrastructure, comprising vegetation such as trees and shrubs, provides many benefits to urban environments. These benefits Environmental and Earth Sciences Research Journal Vol. 10, No. 2, June, 2023, pp. 73-83 Journal homepage: http://iieta.org/journals/eesrj 73