A new study has reinforced the view that biodiversity improvements and greater provision of ecosystem services are complementary. An analysis of projects that restored ecosystems indicated that restoration produced a 44 per cent increase in biodiversity and a 25 per cent increase in the provision of ecosystem services.
Ecological restoration involves helping an ecosystem recover from damage caused by human activity, such as logging or cropping. There is a widespread assumption that restoration increases the provision of ecosystem services although this has not yet been fully tested. As such, the relationship between biodiversity and ecosystem services remains uncertain. However, the EU's recent communication on biodiversity1 pays attention to both biodiversity and ecosystem services and outlines four options for a target to halt their loss.
By examining the effects of restoration the study provided insights into the relationship between increased biodiversity and greater provision of ecosystem services. It analysed 89 published scientific assessments on the outcomes of restoration projects undertaken in a range of ecosystems worldwide. The effects of restoration were analysed on biodiversity (i.e. species abundance and diversity) and on three types of ecosystem services:
The results indicated that, compared with degraded environments, restored environments had greater biodiversity and better 'supporting ecosystem services' and 'regulating ecosystem services', such as nutrient cycling and water supply. However, there was no effect on the 'provisioning ecosystem services', such as timber and crops.
Environments that had suffered no degradation had even greater biodiversity and ecosystem services, indicating that restoration cannot completely erase the effects of degradation. The largest effects of restoration on ecosystem services and biodiversity were in tropical ecosystems, whilst restored temperate aquatic ecosystems only experienced improvements in biodiversity.
The study also explored the relationship between ecosystem services and biodiversity and found a positive association between the two. The results suggested that the impacts of increasing biodiversity on the provision of ecosystem services are stronger when the levels of biodiversity are low. There is a plateau in this effect when biodiversity levels become high.
Ecological restoration is likely to lead to large increases in both biodiversity and ecosystem services, offering a potential win-win solution if the two goals are combined in future restoration projects. However, improved monitoring is needed for both biodiversity and ecosystem service outcomes of restoration projects.
Source: Rey Benayas, J.M., Newton, A.C., Diaz, A. & Bullock, J.M. (2009). Enhancement of Biodiversity and Ecosystem Services by Ecological Restoration: A Meta-Analysis. Science. 28(325): 1121-1124.