Environmental Management of Ecosystem Restoration at Scale: Original Contributions to Theory and Practice from Nigeria’s Great Green Wall Implementation

This dissertation makes original theoretical and practical contributions to the environmental management of ecosystem restoration at scale, drawing on a comprehensive study of Nigeria's implementation of the African Union Great Green Wall Initiative across eleven states in the North West and North East zones. The Great Green Wall, targeting the restoration of 100 million hectares of degraded land across the Sahel by 2030, is the world's largest ecosystem restoration programme, and Nigeria's portion constitutes a significant national environmental management investment whose governance, implementation, and outcome evidence is essential for improving the programme's effectiveness. The dissertation develops an original theory of Large-Scale Ecosystem Restoration Management (LESRM) that identifies the governance architectures, implementation mechanisms, monitoring systems, and community management arrangements most likely to produce durable ecological recovery at the scale required by the Great Green Wall. The LESRM theory integrates insights from restoration ecology, organisational management theory, adaptive management, and common pool resource governance into a coherent management framework. Empirical development combines satellite-based vegetation recovery assessment across 180 restoration sites in nine states, field condition assessment and tree survival monitoring at 60 sites, institutional analysis of the Federal Ministry of Environment Great Green Wall Agency's management structure, community governance assessment at 45 community implementation sites, and process evaluation interviews with 85 programme staff and community participants. The resulting theory generates seven propositions about the conditions for large-scale restoration success, each empirically tested against the Nigerian programme evidence. The dissertation provides a management framework directly applicable to programme improvement. Keywords: ecosystem restoration, Great Green Wall, large-scale management, Nigeria, restoration governance.