Putting a price on nature is not something that our society is instinctively good at. But it’s something businesses will need to get a grasp on if they are to comply with the upcoming Taskforce on Nature-Related Disclosures framework, or participate in the federal government’s Nature Repair market.
As it turns out, one of our most valuable assets is mostly hidden from view and not on our radars. Marine kelp forests provide a whole spectrum of ecosystem services, from supporting fish stocks to nutrient cycling and carbon removal, but until now their monetary value has not been well understood.
A new study published in Nature Communications has done precisely that – estimating the ecological and economic potential of the ecosystem services that kelp forests provide.
Using data from six endemic kelp genera, the forests collectively generate between $465 and $562 billion of value a year worldwide, based on a potential value of between $64,400 and $147,100 a hectare.
Fisheries production from kelp forests generates an average of $29,900 aha annually, nitrogen removal of $73,800 a year and the forests are estimated to sequester 4.91 mega tonnes of carbon from the atmosphere a year, “highlighting their potential as blue carbon systems for climate change mitigation.
“These findings highlight the ecological and economic value of kelp forests to society and will facilitate better informed marine management and conservation decisions,” the research paper noted.
Kelp harvesting has long supported the survival of populations, particularly in Japan, Korea and China where it is consumed by humans and also supports a large food chain of plants and animals. Kelp has been used in Europe to fertilise soil and increase crop yields and treat illnesses caused by iodine deficiency, and are a habitat for abalone, reef fish, lobsters and other fish species.
“We have a deep cultural connection to this ecosystem. But our understanding of the economic value has been lagging other ecosystems competing for conservation funding,” said Dr Aaron Eger, the lead author of the study and the founder and director of the non-profit Kelp Forest Alliance.
“Now, with this study, for the first time, we have the figures to demonstrate the considerable commercial value of our global kelp forests and the financial impetus for advancing kelp conservation and restoration efforts.”
Previous valuations of kelp forests have been produced but they did not directly include fisheries production taking place within the forests.
The study gathered information on the amount of kelp forests in the six genera and then estimated the price that each ecosystem service would fetch if sold in a marketplace.
The focus on potential value is used because “it creates an inventory of resources, highlights potential future value, can identify areas for protection and management, and generates awareness about the socioeconomic importance of an ecosystem”, according to the research paper.
The study also found that around 740 million people live within 50 kilometres of a kelp forest.
Kelp forests are under threat – Tassie has lost nearly all of them
Despite kelp forests’ crucial role in ocean ecosystems and to humans, many are threatened with destruction. In Tasmania, up to 95 per cent of the kelp forest canopy has disappeared. The decline in the kelp forest has been attributed to higher ocean temperatures from warmer waters being pushed southwards to Tasmania via the East Australian current.
“Multiple drivers increasingly threaten kelp forests, so we must understand their economic contribution if we hope to accelerate efforts to save them and the more than 1800 species that rely on them,” Dr Eger, an academic with the University of New South Wales, said.
The Kelp Forest Alliance has launched the Kelp Forest Challenge, which aims to protect and restore four million hectares of Kelp Forest by 2040. Since the challenge began, 14,561 ha of kelp forests have been restored, mostly in South Korea and 3 million ha has been set aside for protection, according to the alliance.
The study did not assess indirect beneficiaries of kelp forests such as tourism and education and kelp as a source of food. Further research could be undertaken to incorporate these factors into future kelp forest valuations, according to Dr Eger.