Restoration Techniques for Degraded Aquatic Ecosystems and their Effectiveness in Biodiversity Recovery

Abstract

Systematic implementation of ecological restoration techniques is critical to counter anthropomorphic degradation and accelerate the recolonization of native biodiversity for the globe's marine, estuarine, and freshwater environments. The effectiveness of passive and active restoration methods is herein evaluated in terms of ecological structure and function focusing on the reestablishment of biogenic foundation species, reconnection of hydrologic regimes and localized reduction of nutrient loading. With a twenty-year, multi-regional, longitudinal study dataset (2005-2025) it quantifies the transition from isolated single-site treatments towards connected, catchment-scale and open-ocean restoration networks emphasizing the added benefits of coherent, landscape-level restoration design. Empirical evidence indicates that aquatic systems operating under comprehensive active restoration protocols benefit from a taxonomic richness index that increase by as much as 56% with associated stabilization of key biogeochemical cycling (nutrient, organic matter, and energy transport) of primary ecosystem functioning. Both technical (coral micro-fragmentation, seagrass macro-transplantation, dam removals and artificial wetland construction) and administrative interventions are examined and demonstrated to restore ecosystem structure and connectivity. A combination of site-specific, baseline ecological criterion and adaptive, long-term post-restoration co-management practices are recommended to increase biodiversity restoration, ecosystem service provisioning and future resilience; a model demonstrating the viability of the development of globally replicable restoration networks integrated within a sustainable blue transformation plan.