By Rod Fujita and Kristin Kleisner 

To mitigate local weather change, sea degree rise, and different environmental issues, some specialists wish to nature-based options. However which options are essentially the most impactful in terms of sequestering carbon? And what will we nonetheless must be taught to enhance our scientific understanding of nature-based options?  

We co-authored a current peer-reviewed research that assessed the scientific foundations of blue carbon and different nature-based resolution pathways. We discovered that our scientific understanding of the advantages of restoration and conservation of terrestrial forests is far stronger than our understanding of the advantages of blue carbon, or carbon sequestered by the ocean. Very like the ocean itself, there are nonetheless many mysteries left to uncover about blue carbon. 

These findings usually are not a motive to cease conserving or restoring blue carbon techniques like mangrove forests, salt marshes, seagrass meadows, and seaweed beds. As an alternative, we view this as a name to double down on analysis that helps deal with key gaps round blue carbon pathways. 

The research factors out that blue carbon efforts are worthy of implementation due to the various social and ecological advantages they supply–even when local weather mitigation advantages are much less sure at this level. 

Eradicating Carbon or Avoiding Emissions? 

The research examined the energy of the science of quantifying carbon dioxide (CO₂) elimination or prevented greenhouse fuel (GHG) emissions, taking a look at every pathway. The outcomes point out that we may be extra assured that mangrove conservation will assist in avoiding giant CO₂ emissions by storing CO₂ in these forests than we may be that mangrove restoration might take away giant quantities of CO₂ from the ambiance. Nevertheless, the research concluded that each pathways nonetheless want extra analysis.   

Why is that this the case? First, whereas mangroves sequester carbon quickly per unit space, mangrove restoration can solely happen in nearshore waters the place the local weather and different elements are conducive to mangrove development. This limits the geographic scope of efforts to revive mangroves and, due to this fact, the size of this pathway.  

Additional, below some circumstances mangrove techniques can launch methane, a robust GHG, which works in opposition to the carbon sequestration advantages. Like mangroves, seagrasses and emergent marshes can sequester carbon quickly and are additionally constrained by their want for appropriate nearshore habitat.  

The sturdiness, or length that carbon is saved, of all blue carbon sinks is unsure as local weather impacts, equivalent to sea degree rise, warming and storms, intensify and grow to be extra frequent.  

Consultants famous that seaweed farming has the potential to attract down average quantities of CO₂, however confidence was low because of main uncertainties about how a lot of the carbon that seaweeds take up will get sequestered over the long run. That is primarily as a result of, regardless that seaweeds can take up carbon very quickly and farming is much less constrained by habitat necessities, marine meals webs convert a few of that carbon again to CO₂. Additionally, the carbon in many of the merchandise created from seaweed (like meals and colloids) returns to the ambiance comparatively rapidly. 

Getting the Science Prepared for the Market 

The science behind many blue carbon pathways should be strengthened if they’re to be included into carbon markets. Though the uncertainty of the science on GHG mitigation by way of mangrove conservation and restoration is comparatively low, scientists don’t but have the arrogance in these pathways that they’ve for temperate and tropical forest conservation and restoration.  

The analysis wanted to convey extra certainty to mangroves’ blue carbon pathways ought to give attention to quantifying emissions of different highly effective GHGs, like methane and nitrous oxide, which might counteract carbon sequestration by these techniques. In different phrases, we have to higher perceive the GHG finances, which might fluctuate in several mangrove techniques, relying on different elements like how degraded the mangrove system is by air pollution or coastal improvement. A greater understanding of the sturdiness of carbon storage by these techniques can also be vital. Environmental Protection Fund is working with companions to do simply that for a mangrove restoration undertaking in Ecuador.  

EDF can also be decreasing uncertainty round carbon sequestration by way of seaweed farming. Research recommend that the realm of the ocean the place seaweed farming might be worthwhile and possible far exceeds the present footprint of seaweed farming. Moreover, in distinction to seaweed-based merchandise like meals and colloids, there are merchandise that might be developed, like development supplies, that retailer carbon or change carbon-intensive merchandise like fossil fuels and plastic. It could even be doable to make seaweed merchandise that suppress GHG emissions, for instance, by producing dietary supplements and components that suppress methane technology by cows or from manure pits.  

Nevertheless, most of those ideas want extra analysis to grasp their potential to sequester or offset GHGs and to grasp pathways to scaling and industrial viability, if acceptable. Additional improvement would require a transparent understanding of the amount of GHG emissions related to farming, processing, and transporting seaweed in addition to on the manufacturing, transport, and disposition of the seaweed merchandise. We’re gathering information at EDF’s demonstration seaweed farm within the Philippines to begin to reply these questions. You’ll be able to be taught extra from our weblog publish protecting what we learn about seaweed’s function in preventing local weather change. 

Blue Carbon Programs Profit Folks and Nature 

It’s clear that blue carbon science should be strengthened to grasp whether or not blue carbon pathways are eradicating as a lot carbon as we predict they’re and to develop financing pathways if these estimates point out that internet GHG mitigation happens. Nevertheless it’s additionally clear that blue carbon techniques produce a number of, well-documented advantages to folks and nature, so the safety of those techniques is vital.   

Mangroves and seagrasses needs to be conserved and restored not solely as a result of they might sequester carbon but in addition as a result of they supply vital habitats for fisheries, present power and vitamins for marine meals webs, and assist marine biodiversity. Sustainable seaweed farming needs to be supported as a result of it could actually generate livelihoods and income for frontline communities struggling essentially the most from local weather change impacts and also can scale back nutrient air pollution and alleviate ocean acidification. These many advantages justify elevated funding in conserving and restoring blue carbon techniques in addition to in increasing sustainable seaweed farming.