MANGROVE forests, known for their rich biodiversity and coastal protection benefits, have gained increasing recognition for their significant role in carbon sequestration.
A recent study conducted in Malaysia’s Sg. Pulai Permanent Reserved Forest sheds light on these forests’ carbon storage capacity, biomass estimation, and economic valuation, offering valuable insights into their environmental and economic importance.
The Role of Mangrove Forests in Carbon Sequestration
Mangroves are unique ecosystems found along tropical and subtropical coastlines, adapted to saline environments and tidal fluctuations.
These forests play a crucial role in mitigating climate change by capturing and storing large amounts of carbon. Studies indicate that mangroves can store up to four times more carbon per hectare than other tropical forests.
However, accurate carbon stock estimations require precise allometric equations tailored to specific species and environmental conditions.
The study in Sg. Pulai Permanent Reserved Forest focused on developing species-specific allometric equations to estimate aboveground biomass.
By measuring the diameter at breast height (DBH) and tree height, researchers derived equations that provide more precise biomass calculations than generic models.
The total aboveground biomass in the study area was found to range between 183.30 t ha-¹ and 187.06 t ha-¹, translating to a carbon stock of 91.01 t C ha-¹.
Methodology: Accurate Estimations for Effective Conservation
The research team conducted field studies in four compartments of the Sg. Pulai forest, representing mixed-species mangrove stands. A total of 1,403 trees across ten species were measured, with Rhizophora apiculata emerging as the dominant species. The study employed the D²H model (incorporating DBH and height) to estimate biomass more accurately than the D model (which uses DBH alone).
The allometric equations developed in this study take the form:
W = aD^b (1)
or
W = aD²H (2)
where W represents the aboveground biomass, D is the DBH, H is the height, and a and b are constants derived from regression analysis.
The total aboveground biomass was calculated by summing the biomass of different tree components:
Total Biomass = Stem Biomass + Branch Biomass + Leaf Biomass (3)
These equations allow for more accurate predictions of biomass, essential for carbon stock estimation and conservation planning.
Economic Valuation of Carbon Stock
Beyond ecological benefits, mangrove forests offer economic value through carbon sequestration. The study employed two valuation methods: the social cost of carbon and the market price approach.
The social cost of carbon method, based on estimates from the U.S. Environmental Protection Agency (EPA), valued carbon storage at USD 4,054.76 per hectare.
In contrast, the market price approach, which considers the trading value of carbon credits, yielded a lower valuation of USD 1,064.34 per hectare.
This disparity highlights the varying perspectives on carbon valuation. While the social cost of carbon accounts for the long-term environmental benefits, market-based valuation focuses on immediate economic incentives.
Integrating these valuation methods into policy frameworks could enhance mangrove conservation efforts by linking ecological preservation with economic incentives.
Key Findings: Biomass and Carbon Stock Distribution
The study revealed the following significant findings:
‘Rhizophora apiculata’ was the most dominant species in the study area.
The total aboveground biomass was estimated at 183.30 t ha-¹.
The total carbon stock, including trees below 5 cm DBH, deadwood, and litter, was 91.01 t C ha-¹.
Deadwood contributed 1.24 t C ha-¹, while litter accounted for 1.08 t C ha-¹.
The carbon content varied across tree components, with stem wood showing higher carbon concentration than leaves and branches.
These findings provide a foundation for future conservation strategies by highlighting the structural and species-specific differences in biomass distribution.
Implications for Conservation and Policy
The study underscores the importance of site-specific allometric equations in carbon stock estimation. Current global estimates often rely on generic models that may not accurately reflect local variations.
By incorporating region-specific equations, policymakers can make informed decisions regarding mangrove conservation and carbon trading initiatives.
Moreover, the research highlights the potential for integrating mangrove conservation into carbon credit markets. With carbon trading gaining traction globally, accurately quantifying mangrove carbon stocks could open new avenues for financing conservation projects.
By assigning economic value to carbon sequestration, stakeholders including governments, conservation organisations, and local communities can be incentivized to protect these critical ecosystems.
Future Research and Recommendations
While the study provides robust data on aboveground biomass and carbon stocks, further research is needed to assess belowground carbon pools.
Mangroves store significant amounts of carbon in their root systems and sediments, which were not included in this study.
Future studies should integrate belowground carbon measurements to provide a comprehensive assessment of total ecosystem carbon stocks.
Additionally, the application of remote sensing technologies, such as LiDAR and satellite imagery, could enhance biomass estimation accuracy.
These tools offer non-destructive methods for large-scale biomass assessments, complementing field measurements.
Conclusion
Mangrove forests are invaluable in the fight against climate change, serving as powerful carbon sinks while providing essential ecological and economic benefits.
The study conducted in Sg. Pulai Permanent Reserved Forest highlights the importance of accurate biomass estimation using site-specific allometric equations.
With a total aboveground carbon stock of 91.01 t C ha-¹, these forests play a crucial role in carbon sequestration.
By assigning economic value to carbon storage, the study emphasises the potential for integrating mangrove conservation into carbon credit markets.
Policymakers and conservationists can leverage these findings to develop strategies that balance ecological preservation with economic incentives.
Moving forward, expanding research to include belowground carbon stocks and remote sensing applications will further refine carbon estimation techniques, strengthening global climate mitigation efforts.
As mangrove ecosystems face increasing threats from deforestation and climate change, research-driven conservation efforts will be pivotal in safeguarding their future.
By recognising and quantifying their role in carbon sequestration, we can ensure that mangrove forests remain a cornerstone of global climate resilience strategies.
Further information can be found from the following link https://www.sciencedirect.com/science/article/pii/S266597272500039X
Waseem Razzaq Khan (PhD), Consultant Fellow; Faculty of Forestry and Environment, University Putra Malaysia; Visiting Professor,Pingtan Research Institute of Xiamen University; Associate Editor: Tropical Conservation Science (TCS); Editor: Discover Forests; email: waseemjatoi4@gmail.com
The views expressed here are those of the writer and do not necessarily represent the views of the Sarawak Tribune.
