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.

Mangrove degradation, Above-ground biomass, Ecosystem stress theory

Adame, M. F., Baumeister, J., & Risheharan, K. (2025). Exploring the practical applications of floating mangroves and their potential impacts. In Concepts at the Edge of the Anthropocene. Springer. https://link.springer.com/chapter/10.1007/978-981-96-0357-2_8

Akram, H., Hussain, S., Mazumdar, P., Chua, K. O., & Butt, T. E. (2023). Mangrove health: A review of functions, threats, and challenges associated with mangrove management practices. Forests, 14(9), 1698. https://doi.org/10.3390/f14091698

Al-Huqail, A. A., et al. (2025). Stress-resilience modeling in degraded coastal ecosystems.

Ecological Indicators. https://doi.org/10.1016/j.ecolind.2025.112678

Al-Huqail, A. A., Islam, Z., & Al-Harbi, H. F. (2025). Ecological stress modeling to conserve mangrove ecosystems along the Jazan Coast of Saudi Arabia. Land, 14(1), 70. https://doi.org/10.3390/land14010070

Alongi, D. M. (2020). Blue carbon ecosystems and climate change mitigation. Ocean & Coastal Management, 189, 105154. https://doi.org/10.1016/j.ocecoaman.2020.105154

Altarez, R. D. D., Apan, A., & Maraseni, T. (2022). Spaceborne satellite remote sensing of tropical montane forests: A review of applications and future trends. Geocarto International. https://doi.org/10.1080/10106049.2022.2060330

Bas, T. G., Sáez, M. L., & Sáez, N. (2024). Sustainable development versus extractivist deforestation in tropical, subtropical, and boreal forest ecosystems: Repercussions and controversies. Plants, 13(9), 1231. https://doi.org/10.3390/plants13091231

Bhowmik, A. K., Padmanaban, R., & Cabral, P. (2022). Global mangrove deforestation and its interacting social-ecological drivers. Sustainability, 14(8), 4433.

https://doi.org/10.3390/su14084433

Cabral, P., Bhowmik, A. K., Padmanaban, R., & Romeiras, M. M. (2022). Social-ecological dynamics in mangrove degradation. Sustainability, 14(8), 4433.

https://doi.org/10.3390/su14084433

Chaiklang, P., Karthe, D., & Babel, M. (2024). Land use transitions and mangrove deforestation in Thailand. Trees, Forests and People, 13, 100183.

https://doi.org/10.1016/j.tfp.2024.100183

Chaiklang, P., Karthe, D., Babel, M., & Giessen, L. (2024). Reviewing changes in mangrove land use over the decades in Thailand: Current responses and challenges. Trees, Forests and People, 13, 100183. https://doi.org/10.1016/j.tfp.2024.100183

Chaudhary, S., & Ghosh, T. (2022). Environmental assessment of mangrove health using biochemical indicators. Ecological Indicators, 140, 109039.

https://doi.org/10.1016/j.ecolind.2022.109039

Chinembiri, T. S., Mutanga, O., & Dube, T. (2024). Bayesian geostatistical modeling of forest carbon. Global Environmental Change, 84, 103130.

https://doi.org/10.1016/j.gloenvcha.2024.103130

Chinembiri, T. S., Mutanga, O., & Dube, T. (2024). Leveraging climate and remote sensing metrics for predicting forest carbon stock using Bayesian geostatistical modelling. Global Environmental Change, 84, 103130. https://doi.org/10.1016/j.gloenvcha.2024.103130

Chinembiri, T. S., Mutanga, O., & Dube, T. (2024). Modeling biomass loss using remote sensing and Bayesian networks. Global Environmental Change, 84, 103130. https://doi.org/10.1016/j.gloenvcha.2024.103130

Cobacho, S. P., van de Leemput, I. A., & Holmgren, M. (2024). Biogeochemical fluxes in tropical seascapes. Marine Environmental Research. https://doi.org/10.1016/j.marenvres.2024.106240

Dasgupta, R., Hashimoto, S., Saizen, I., & Bimrah, K. (2022). Ecosystem services of mangroves: A systematic review and synthesis of contemporary scientific literature. Sustainability, 14(19), 12051. https://doi.org/10.3390/su141912051

Dunn, F. E., Cox, J. R., Scown, M., Du, H., & Triyanti, A. (2023). Sedimentation-enhancing strategies for sustainable deltas: An integrated socio-biophysical framework. One Earth, 6(10), 1045–1062. https://doi.org/10.1016/j.oneear.2023.09.008

Fatoyinbo, T. E., Lagomasino, D., et al. (2021). Carbon stock loss from mangrove deforestation in the Niger Delta. Environmental Research Letters. https://doi.org/10.1088/1748- 9326/abcdee

Ghosh, S. M., Behera, M. D., Jagadish, B., & Das, A. K. (2021). A novel approach for estimation of aboveground biomass of a carbon-rich mangrove site in India. Journal of Environmental Management, 283, 111976. https://doi.org/10.1016/j.jenvman.2021.111976

Giri, C., Long, J., & Tieszen, L. (2022). Monitoring mangrove forest dynamics in Southeast Asia. Remote Sensing of Environment, 267, 112729. https://doi.org/10.1016/j.rse.2021.112729

Kauffman, J. B., & Donato, D. C. (2012). Protocols for the measurement, monitoring and reporting of structure, biomass and carbon stocks in mangrove forests. Center for International Forestry Research. https://doi.org/10.17528/cifor/003749

Komiyama, A., Ong, J. E., & Poungparn, S. (2008). Allometry, biomass, and productivity of mangrove forests: A review. Aquatic Botany, 89(2), 128–137. https://doi.org/10.1016/j.aquabot.2007.12.006

Komiyama, A., Ong, J. E., & Poungparn, S. (2021). Global synthesis on mangrove biomass allocation and productivity. Ecological Indicators, 128, 107754. https://doi.org/10.1016/j.ecolind.2021.107754

Lee, H. L., Lee, V. S., & Md Akil, M. A. M. (2025). Malaysia's progress in achieving the United Nations Sustainable Development Goals (SDGs) through the lens of chemistry. Pure and Applied Chemistry. https://doi.org/10.1515/pac-2024-0233

Mello, F. A. O., Ferreira, T. O., Bernardino, A. F., & Queiroz, H. M. (2024). Soil health and ecosystem services in mangrove forests: A global overview. Water, 16(24), 3626. https://doi.org/10.3390/w16243626

Mitra, A., Zaman, S., & Sahu, B. (2023). Evaluating toxic metal accumulation in mangrove soils. Environmental Monitoring and Assessment, 195(3), 377. https://doi.org/10.1007/s10661- 023-10962-z

Rashid, M. B., Habib, M. A., Islam, M. S., & Khan, R. (2024). Synthesis of drainage characteristics and sediment supply in the Bengal basin. Quaternary Science Advances. ResearchGate PDF

Romeiras, M. M., Bhowmik, A. K., et al. (2022). Global mangrove degradation: A systematic review. Sustainability, 14(8), 4433. https://doi.org/10.3390/su14084433

Rudianto, R., Bengen, D. G., & Kurniawan, F. (2020). Causes and effects of mangrove ecosystem damage on carbon stocks in East Java, Indonesia. Sustainability, 12(24), 10319. https://doi.org/10.3390/su122410319

Sani, D. A., Hashim, M., & Hossain, M. S. (2019). Recent advancement on estimation of blue carbon biomass using satellite-based approach. International Journal of Remote Sensing, 40(18), 7150–7175. https://doi.org/10.1080/01431161.2019.1601289

Saoum, M. R., & Sarkar, S. K. (2024). Monitoring mangrove forest change and its impacts on the environment. Ecological Indicators, 158, 113112.

https://doi.org/10.1016/j.ecolind.2024.113112

Schuh, M. (2023). Estimation of above-ground biomass in dense Amazonian forest using airborne LiDAR and satellite imagery. Federal University of Santa Maria Repository. https://repositorio.ufsm.br/handle/1/30289

Shankar, V., & Verma, R. (2024). Contaminant uptake in mangrove biomes. Marine Pollution Bulletin. https://doi.org/10.1016/j.marpolbul.2024.115760

Simard, M., Fatoyinbo, T. E., & Lagomasino, D. (2021). Mangrove canopy height and biomass mapping using remote sensing. Environmental Research Letters, 16(2), 025003. https://doi.org/10.1088/1748-9326/abce6a

Simard, M., Fatoyinbo, T., & Lagomasino, D. (2021). Mapping mangrove canopy height and biomass using remote sensing. Environmental Research Letters, 16(2), 025003. https://doi.org/10.1088/1748-9326/abce6a

Sun, W., Deng, H., He, J., Feng, D., Zhao, Y., & Yu, H. (2021). Microplastics pollution in mangrove ecosystems: A critical review of current knowledge and future directions. Science of The Total Environment, 764, 144610. https://doi.org/10.1016/j.scitotenv.2020.144610

Sundaramanickam, A., Nithin, A., et al. (2021). Role of mangroves in pollution abatement. In Mangroves: Ecology, Biodiversity and Management. Springer. https://doi.org/10.1007/978-981-16-2494-0_11

Tahiluddin, A. B., & Bornales, J. C. (2025). Environmental impacts of aquaculture. Israeli Journal of Aquaculture. https://ija.scholasticahq.com/article/133778.pdf

Teshager, Z., & Soromessa, T. (2025). Remote sensing in forest diversity assessment.

ResearchSquare (preprint). https://www.researchsquare.com/article/rs-6105040/latest

undaramanickam, A., Nithin, A., et al. (2021). Role of mangroves in pollution abatement. In Mangroves: Ecology, Biodiversity and Management. Springer. https://doi.org/10.1007/978-981-16-2494-0_11

Varshney, S. (2024). From nanoplastics to chemical pollutants: Exploring mixture toxicity in zebrafish. Nord University Environmental Research Report https://nordopen.nord.no/nord- xmlui/bitstream/handle/11250/3134115/Varshney.pdf

Virgulino-Júnior, P. C. C., Carneiro, D. N., et al. (2020). Biomass and carbon estimation for scrub mangrove forests and examination of their allometric associated uncertainties. PLOS ONE, 15(3), e0230008. https://doi.org/10.1371/journal.pone.0230008

Ward, R. D. (2025). Mangrove forests: Impacts of climate change and mitigation potential. In Mangroves in the Anthropocene: Climate Adaptation and Community Resilience (pp. 35– 54).https://ii-es.com/wp-content/uploads/2025/05/Mangroves-in-the Anthopocene.pdf#page=35

Yin, D., & Wang, L. (2019). Individual mangrove tree measurement using UAV-based LiDAR data. Remote Sensing of Environment, 223, 34–49. https://doi.org/10.1016/j.rse.2018.12.034

Yu, C., Liu, B., Deng, S., Li, Z., & Peng, X. (2023). Evaluating recent changes and future trends of mangrove forests on Hainan Island. Forests, 14(11), 2217. https://doi.org/10.3390/f14112217