Kelp forests – the unknown climate saviours: What exactly is it all about?
Kelp forests are fascinating and of great importance for marine ecology, but largely unknown. Like many other marine ecosystems, their existence is threatened by both climate change and human influences in general.
Kelp forests are underwater forests. They are formed primarily from seaweed plants. The plants have long, spongy stems with large, broad leaves that float on the water surface. Kelp forests are home to an enormous variety of species. They contribute significantly to the productivity and health of the oceans. They occur in the cold waters of the subpolar climate zone in the Northern Hemisphere and in other temperate regions. Example regions are the west coast of North America, the Cape Horn region, large parts of South Africa and Australia.
The performance balance of kelp forests
Kelp forests are centres of marine biodiversity. Their dense vegetation provides shelter and food for fish such as Pacific salmon and sea bass. For mammals such as sea lions and otters, they are hunting grounds, but also hiding places from predators. Kelp forests play a major role in carbon storage. They therefore contribute directly to reducing the concentration of CO2 in the atmosphere and help combat global warming.
During their growth phase, kelp algae absorb large amounts of carbon and store it in their biomass. When the algae die and sink into the deep sea, the bound carbon is stored on the seabed. The contribution of kelp forests in protecting coastal areas from erosion should not be forgotten. Their dense structure breaks the waves and reduces their force. This means that less wave energy hits the coastal regions and protects their stability.
Impacts of Climate Change on Kelp Forests
Kelp forests are at great risk from climate change. The warming of the oceans is already having a significant impact on the sensitive seaweed plants. Kelp algae in particular are sensitive to high water temperatures. They die if the water is too warm for a long period of time. The result is a decline in kelp stocks. This means that the species that use the kelp forest habitat also lose their food source. Another consequence is ocean acidification, triggered by the increased CO2 content in the atmosphere.
The more acidic pH value of the water hinders the growth and development of kelp algae. Changes in ocean currents also have a negative impact on kelp forests. In some regions, kelp forests are being observed to be declining because ocean currents are transporting important nutrients away from these habitats.
Restoration of kelp forests
The increased establishment of marine protected areas can help prevent the destruction of kelp forests. Above all, however, reducing CO2 emissions as the main driver of climate change is necessary. Both measures are rather uncertain in terms of their implementation, which makes the restoration of kelp forest structures necessary in parallel. In addition to the initiatives of numerous non-governmental organizations (NGOs), some of which I have linked at the end of this article, the United Nations program for the restoration of marine habitats is in the foreground.
The UN Decade of Ocean Science for Sustainable Development has been running since 2021. Various action plans support efforts to halt and reverse the decline of the marine biosphere. However, large investments in the preservation of marine ecosystems are necessary.
Initiative: Program plan from 2021 to 2030
Despite a long history with initiatives from Japan, Korea and California, the science and practice of kelp forest restoration is still in its infancy. However, it is currently being accelerated considerably by numerous science-based initiatives. These have resulted in the United Nations' Kelp Restoration Guidebook. I have also linked this at the end of the article. The measures described in it were supported by a series of global workshops.
A permanent panel of experts made up of scientists aims to share and optimise all lessons learned from kelp forest restoration efforts. The aim of the project, which will run until 2030, is to create a solid methodology and a large network of experts in the field of kelp forest restoration. The United Nations, together with many NGOs, has very clearly recognised how important kelp forests, which are largely unknown to the public, are in a world changing due to climate change, and in particular in the changing seas of our planet.
Sources:
UN initiative to restore kelp forests
Download link to the guidebook