Flood risk assessment through rapid urbanization LULC change with destruction of urban green infrastructures based on NASA Landsat time series data: A case of study Kuala Lumpur between 1990–2021

Abstract

Kuala Lumpur, as one of the fastest growing cities in the world, is facing significant negative impacts on its urban ecosystem services (UESs) due to rapid urbanization. Among the classes of land use and land cover (LULC) in Kuala Lumpur, urban green infrastructure (UGI) plays a crucial role in mitigating these impacts. The present study aimed to evaluate the amount of UGIs in Kuala Lumpur for a better understanding of hydro-meteorological hazards assessment. To this end, historical data from 1990 to 2021 were collected using NASA Landsat 4 and Landsat 8 to evaluate the past and current tendencies of LULC in Kuala Lumpur. Various techniques and software, including Markov Chain, ArcGIS, and TerrSet, were utilized to examine the interactions and interpret and create maps. Six categories of land were defined, including grass, waterbodies, soil, buildings, urban forest trees, and urban trees. The study utilized Landsat's Normalized Difference Vegetation Index (NDVI) to analyze the impact of modifications on UGIs. Additionally, the Landsat Normalized Difference Water Index (NDWI) was employed to illustrate changes in urban water values. The findings revealed a significant decline in urban forest trees from 15.99% in 1990 to 6.5% in 2021, resulting in an increase in urban water values and an increase in flooding. The NDWI values in 1990 ranged between 0.383635 and −0.593184, while by 2021, they had fallen to between 0.593288 and −0.44379. These changes in NDVI and NDWI have contributed significantly to the intensity and frequency of urban flooding in Kuala Lumpur.