The Climate Crisis

Seven years ago, the infamous Paris Agreement was signed. It was this international treaty that saw world leaders agree to limit their countries greenhouse gas (GHG) emissions on a pursuit to prevent global temperatures from rising. Legally binding targets were set to prevent temperatures from rising 2°C above pre-industrial levels with the ultimate goal of limiting the rise to under 1.5°C.

Unfortunately, fossil fuels have continued to be burnt (e.g. coal, oil, and gas), releasing copious amounts of carbon dioxide (CO2), and other potent gases such as methane and nitrous oxides into the atmosphere. An increase in GHG emissions is directly associated with rising temperatures, and the negative impacts associated with this phenomenon are worsening. Impacts are beginning to be documented more frequently, which includes an increase of storms, heat waves, floods, and droughts which all have associated indirect impacts e.g., wildfires leading to the loss of life and homes.

Here at Mossy Earth, we are currently focusing on two blue carbon ecosystems: seagrass meadows and kelp forests. Both these ecosystems provide boundless benefits to both marine life as well as humans, in addition to their unique capacity to sequester CO2. They are key to the survival of our oceans, which is why we are acting now, to help aid in the restoration of both habitats through a variety of partnerships and projects.

See the end of this article to find out exactly how we're trying to scale up restoration efforts in Europe. But first, let's dive more into the benefits of these blue carbon ecosystems.

The Forests of the Sea

Kelp belongs to the order of Laminariales and is a brown macroalgae, otherwise known as a seaweed. They cling to the rocky seabed with their holdfasts (a root-like system), and form long and slender fronds of up to 30m that grow quickly towards the ocean’s surface. Light glistens through the water column, where they feed from the sun's energy (photosynthesis) to grow and form dense kelp forests.  Through this process, carbon dioxide is removed from the atmosphere and converted and stored into various parts of the organism (the stipe, the fronds, the bladders, and the holdfast etc). Kelp forests occupy 25% of the world’s coastlines, where they prefer cold, nutrient-rich waters, so they are mainly associated with temperate and polar waters. Here are more fascinating facts about kelp.

• Kelp forests have some of the highest rates of primary production of any natural ecosystem, however in the past 50 years, global kelp abundances have declined by ~2% per year.
• Kelp forests, alike seagrass meadows harbour a great amount of biodiversity, which relies on thousands of finely balanced species interactions. If one or more of the species are lost, the entire system could be at risk of collapse. This has been devastatingly demonstrated in the kelp forests on the West Coast of America, where Sea Star Wasting Disease has caused a mass die back of sea stars.
• Purple sea urchins, who have a ravenous appetite for kelp, are the sea star's main prey. Without the sea stars to predate on the urchins their numbers are growing unchecked, devouring kelp forests at an unstoppable rate leaving behind ‘urchin barrens’.
• Unfortunately, urchins aren’t the only threat to kelp forests, human activities such as overfishing, pollution and climate change (i.e. rising water temperatures and harsher storms) are also a cause for worry.

Both ecosystems support a vast amount of biodiversity, by supplying habitats for thousands of species where they seek food and shelter. They also protect the coastline from erosion by stabilising sediments and reducing the impact of waves. But let us not forget, the other major attribute these ecosystems are capable of, and this is their capacity to absorb and store carbon.

Trialing Seedling Techniques

Since forming a partnership with SeaForester in 2020, an initiative that aims to restore and reverse the decrease in seaweed forests around the world, we've launched several projects.

The first was based in Cascais, Portugal, and aimed to test a seedling technique using spore bags that are attached to rock surfaces. The mesh bags carried reproductive structures that would release spores and settle onto the rock to form new patches of kelp. Unfortunately this technique was not successful. We believe this was due to the amount of turf algae, which despite removing it from the rock surface beforehand, it outcompeted the kelp for space on the rocks.

As disappointing as this was, we felt it served as a valuable finding in our research and led us to develop a new approach with greater potential of scaling up restoration.