Developing an Integrated Framework for Assessing Environmental Management Carrying Capacity in Nigerian Urban Ecosystems

This dissertation develops an original integrated framework for assessing environmental management carrying capacity in Nigerian urban ecosystems, making theoretical and methodological contributions to the concept of urban environmental carrying capacity that are grounded in the specific institutional, ecological, and social conditions of rapidly growing Nigerian cities. Environmental management carrying capacity, the maximum level of urbanisation and associated environmental stress that an urban ecosystem can sustain without irreversible degradation of critical environmental services, is a conceptually powerful but methodologically underdeveloped construct, particularly for cities in the Global South where data constraints and institutional complexity challenge adaptation of Western urban ecology frameworks. The theoretical contribution involves constructing a novel multi-dimensional carrying capacity framework that integrates four sub-capacity domains: biophysical carrying capacity (ecosystem service provision limits), infrastructure management capacity (waste, water, and drainage service capacity relative to demand), regulatory institutional capacity (the ability of governance systems to enforce environmental standards under growth pressure), and community adaptive capacity (the resilience of community environmental management practices under urbanisation stress). The framework is operationalised through empirical calibration at three Nigerian cities of different size and growth trajectories: Lagos, Enugu, and Yola. For each city, carrying capacity threshold indicators are quantified through satellite data analysis, infrastructure performance assessment, institutional capacity measurement, and community survey. Validation testing applies the framework to predict observed environmental condition deterioration trajectories. Original contributions include the four-domain framework, the Nigerian urban ecological indicator set, and a dynamic capacity monitoring protocol for urban environmental management authorities. Keywords: carrying capacity, urban ecosystem, environmental management, Nigerian cities, sustainability.