Assesing the Impact of Urban Sprawl on Wetland Ecosystems

Abstract

Urban sprawl, a phenomenon driven by rapid urbanization, poses significant threats to worldwide wetland ecosystems. One of the problems that land managers face currently is the lack of knowledge on how the wetland ecosystems and their services have been affected by the uncontrolled urban sprawl, particularly in Makindye Kampala. This study aimed to assess the multifaceted impacts of urban sprawl on wetland ecosystems through a comprehensive analysis. Remote sensing data specifically Landsat images from 2004, 2014 and 2024 coupled with interviews and field observation were used in this study. The images were analysed through the Urban Expansion Intensity Index, Shannon’s entropy analysis, ecosystem service market-based analysis, change detection, hot spot analysis and correlation analysis. It is revealed that between 2004 and 2014 there was a moderate urban expansion rate with an intensity of 0. 96. However between 2014 and 2024, the rate of urban expansion was very high with an intensity of 1.12. This urban expansion had high rates of dispersion with an entropy rate of 0.99. Furthermore, findings reveal an extensive conversion of wetlands into urban land uses with a percentage decrease from 23.56 to 10.32 per cent between 2004 and 2024.This has resulted in habitat loss, alteration of hydrological regimes, and degradation of water quality. Quantification of the loss of ecosystem services provided by wetlands, such as flood mitigation, water purification, and biodiversity conservation revealed a loss of -18.95 per cent between 2014 and 2014. Correlation analysis revealed a strong negative relationship between urban sprawl and wetland ecosystems. Findings underscore a need for a multifaceted land management approach through development control, and strategic planning, advocating for compact and mixed-use developments while demarcating zones of urban development for efficient planning and management to curb uncontrolled outward development of the urban area boundaries