Study highlights potential impacts of biodiversity loss on key services

Cordis: Biodiversity loss could have a more serious impact than was previously thought on vital ecosystem services such as food production and clean water supply, scientists warn. The study, which is published in the journal Nature, draws on results from the EU-funded BIODEPTH project.

We rely on ecosystems for a range of essential services including the provision of food and materials, the capture of carbon dioxide from the atmosphere, the provision of clean water, the protection of soils from erosion and as a source of wild genes that may be useful in agriculture or medicine. Many studies have found that ecosystem services depend on a certain number of species to work effectively. However, these studies all looked at ecosystem services individually, whereas in fact most ecosystems are valued or managed for several services or processes, so-called 'multifunctionality'.

Now Professor Andy Hector of the University of Zurich and Dr Robert Bagchi of the University of Oxford have developed a new method to investigate several ecosystem processes in the same analysis. In this latest piece of research, they apply this method to data collected during the BIODEPTH project, which brought together eight biodiversity experiments that manipulated plant biodiversity in grasslands and monitored the response of a variety of ecosystem processes.

They found that higher levels of biodiversity were needed when all seven of the measured ecosystem services were taken into account than when focusing on any single ecosystem service on its own.

'Previous analyses have been too narrowly focused and have effectively assumed that the species that are important for one ecosystem service can provide all the other services too - but that doesn't seem to be the case,' said Professor Hector.

In fact the analysis revealed that different ecosystem services were affected by different groups of species. 'Because different species influence different ecosystem services more species are required for a fully-functioning ecosystem than for one managed with a single goal in mind,' explained Dr Bagchi.

'Studies focusing on individual processes in isolation will underestimate levels of biodiversity required to maintain multifunctional ecosystems,' the researchers warn in their article.

The two scientists are now testing their ideas further in the tropics. Professor Hector is working on a project in Borneo which is studying whether tree re-planting schemes are more successful if they use a diverse range of species than the monocultures which are usually planted. Meanwhile Dr Bagchi is investigating tropical forest biodiversity in Belize.