Mangrove Deforestation And Pollution: Impacts On Above-Ground Biomass And Ecosystem Health
Read Abstract
Mangrove ecosystems are globally recognized for their vital ecological services, including coastal protection, carbon sequestration, and biodiversity support. However, these ecosystems are increasingly threatened by deforestation and environmental pollution, drivers that synergistically diminish above-ground biomass (AGB) and impair ecosystem functionality. This study addresses a critical research gap in the West African context by evaluating how deforestation and pollution jointly affect the structural and functional integrity of mangroves in Eagle Island, River state in the Niger Delta. The primary objectives were to elucidate spatial degradation patterns, quantify biomass loss, and propose actionable frameworks for sustainable mangrove ecosystem management under intensifying anthropogenic pressure. Grounded in Ecosystem Stress Theory and Resource Limitation Theory, the study employed a stratified field research design across three ecological disturbance zones. Data collection combined biometric measurements of dominant mangrove species (Rhizophora racemosa, Avicennia germinans, Laguncularia racemosa) with physicochemical analysis of sediment quality (e.g., cadmium, lead, zinc, THC). Standardized allometric equations were used to estimate AGB, and inferential statistics, including one-way ANOVA and Tukey HSD were applied to identify significant differences in biomass and soil pollutants across disturbance gradients. Data were log-transformed for normality and analyzed using R statistical software. Results revealed a significant reduction in AGB (exceeding 50%) in high-disturbance zones, correlating strongly with elevated cadmium and hydrocarbon levels. Sediment in deforested plots showed 18-fold increases in cadmium and a 3-fold increase in THC relative to forested areas, indicating severe substrate degradation. Species-specific pollutant data showed that Rhizophora racemosa accumulated the highest metal and hydrocarbon concentrations, suggesting potential use as a bioindicator species. Soil quality, biogeochemical resilience, and primary productivity were consistently compromised under combined deforestation and pollution, affirming both theoretical models. The research finds that pollution and deforestation create interactive, compounding stresses that significantly harm ecosystems. These results emphasize the need for combined management techniques and offer empirical confirmation of ecological threshold models. Recommendations include enhanced pollutant regulation, species-informed reforestation, and sediment remediation protocols to restore mangrove function and resilience in the Niger Delta and similar ecologically vulnerable regions.