New way of understanding Earth's ecosystems could help to restore them

A new way of defining ecosystems has been launched, which will help refine plans to restore the world's biodiversity.

The Global Typology of Ecosystems, a systematic way of characterising all of the Earth's ecosystems, is the result of several years of work by dozens of scientists from all over the world.

Published in Nature, it details the core components and functions of each ecosystem of the world, providing the basis for targets that conservationists and governments can act on.

At the same time, it acknowledges that we know little about some areas of the world that are vital to our survival.

Dr Neil Brummitt, a Principal Researcher at the Museum who co-authored the paper, says, 'While the typology won't change the situation on the ground overnight, it is designed so that ecosystems from different countries can be compared more easily.'

'By combining a high-level approach that reflects the well-defined functions of an ecosystem with a bottom-up approach that shows its composition, this flexibility will allow the combination of global analysis with the knowledge of local people to gain a better understanding of different ecosystems.'

The typology has already been adopted by the International Union for the Conservation of Nature (IUCN), which monitors not only the conservation status of animal and plant species but also of ecosystems in its Red Lists. 

The IUCN's Director General, Dr Bruno Oberle, says, 'Many of the world's ecosystems are under acute risk of collapse, with grave consequences for the survival of species, genetic diversity, ecosystem services and human wellbeing.' 

'To sustain them, it's critically important that the post-2020 Global Biodiversity Framework contains explicit, ambitious goals for the conservation of ecosystems alongside species. This first standardised, spatially explicit ecosystem typology provides the infrastructure that is needed to set and track such goals.' 

What is the Global Typology of Ecosystems?

While it may be straightforward to distinguish a sandy desert from the deep sea, it isn't always as easy to tell apart more similar environments.

For instance, lowland tropical rainforest growing in a mountainous area will gradually give way to tropical montane forest as the elevation rises. But where exactly does the dividing line between both ecosystems lie? 

This is where the typology comes in, which classifies different environments according to increasingly specific characteristics. 

For instance, classifying the Amazon rainforest would first start with the broadest category, either terrestrial, freshwater, marine, subterranean or atmospheric. This is known as the realm, and so the Amazon's realm would be terrestrial, along with all other life on the land surface of the Earth. 

Next is the environments' biome. This represents how the ecosystem's vegetation is broadly structured, with the Amazon part of the tropical-subtropical forest biome. 

The biome is then split into ecosystem functional groups which define specific environmental factors like high rainfall and processes like high nutrient cycling that set the Amazon apart from other types of tropical forest. The Amazon's functional group is lowland tropical rainforest.

Further down the typology's hierarchy, the categories move from the function of an ecosystem to emphasising its composition, using locally sourced information to account for differences in geography and species. 

The fourth level of the typology refers to the unique variants of a functional group. The Amazon would be its own variant as it is distinct from other rainforests around the world. The fifth and sixth levels of the typology, global and subglobal ecosystem types, refer to groups of organisms that live within the environments.

Information about the bottom three tiers of the typology is gathered at a local level, so this section of the typology is designed to work with national governments and individuals to utilise their specialist knowledge. This can then be built up over time and integrated into the typology's upper levels.

'We don't want to impose a set of scientific decisions that might adversely impact the efforts of individuals and nations around the world,' Neil says. 'The aim is that local people can contribute their knowledge to build up a detailed picture of ecosystems at a global scale.' 

What can the global typology of ecosystems be used for?

Over time, every country on Earth can have the health of its ecosystems assessed under the typology. The Maldives has already undergone this process, and it is hoped that more countries will follow its lead.

Once these assessments have taken place, it will be much easier to produce realistic, targeted action plans to preserve different habitats. Strategies which work in one area can be tailored for use in similar ecosystems in different places, based upon where they lie in the typology.

Professor David Keith, the lead author of the typology, says, 'By grouping similar ecosystems according to their characteristics and functions, this new typology reveals patterns that might otherwise remain hidden.' 

'It will allow us to recognise similarities between related ecosystems and to apply what we learn about sustainable management of estuaries in China, for example, to similar estuaries in Nigeria. Understanding the common risks that similar ecosystems face ultimately helps to develop ways to protect them.'

The typology may also be helpful for widening the use of natural capital accounting, where the value of ecosystems is incorporated into wider economic decisions. For instance, the cost of damage to the ecosystem services that a woodland provides could be compared against the income raised by its deforestation to assess their financial implications.

It will also form part of the wider analysis of how humans are impacting the world. The Amazon, for instance, is thought to be nearing a tipping point where it might transition from rainforest into savannah, and the typology could be used to confirm where and when this is happening.

However, there are large barriers facing the typology before it can be adopted worldwide, as Neil explains. 

'There are significant research gaps for many ecosystems at fine detail,' Neil says. 'Filling these gaps is a huge challenge that will need years of work by many people, but there is currently no funding or co-ordinating mechanism to achieve this.'

'There is also the potential that legislation protecting specific ecosystems could be challenged if the typology redefines what that ecosystem is, and this will require careful consideration.'

While these barriers may take some time to overcome, the benefits of classifying the world's ecosystems would be immense not only economically, but also scientifically.

'The typology will produce an incredibly powerful and useful tool when combined with granular maps of the world's ecosystems,' Neil says. 'It could also work alongside other projects, such as our Plants Under Pressure programme at the Museum, to compare threats facing individual species and entire ecosystems.'

With the COP15 UN biodiversity conference set to conclude in December, researchers hope that this new typology will be a further tool to help delegates agree accurate and equitable targets to help protect life on Earth.