A global synthesis reveals biodiversity loss as a major driver of ecosystem change

Although loss of biodiversity is known to cause reduction in ecosystem function, it is not known how this threat compares to other environmental alterations such as climate change; this analysis of the data from over 100 published studies shows that biodiversity loss is as significant as other major drivers of change in ecosystem function. Biodiversity loss drives change It is well established that loss of biodiversity causes a reduction in ecosystem function, but it is not clear how big a threat this poses to function compared with the more direct influences from changes in climate, atmospheric chemistry and nutrient pollution. This analysis of data from 192 published studies shows that the impact of biodiversity loss on ecosystem processes is equal to, or larger than, the effects of most other drivers of environmental change. Evidence is mounting that extinctions are altering key processes important to the productivity and sustainability of Earth’s ecosystems 1 , 2 , 3 , 4 . Further species loss will accelerate change in ecosystem processes 5 , 6 , 7 , 8 , but it is unclear how these effects compare to the direct effects of other forms of environmental change that are both driving diversity loss and altering ecosystem function. Here we use a suite of meta-analyses of published data to show that the effects of species loss on productivity and decomposition—two processes important in all ecosystems—are of comparable magnitude to the effects of many other global environmental changes. In experiments, intermediate levels of species loss (21–40%) reduced plant production by 5–10%, comparable to previously documented effects of ultraviolet radiation and climate warming. Higher levels of extinction (41–60%) had effects rivalling those of ozone, acidification, elevated CO 2 and nutrient pollution. At intermediate levels, species loss generally had equal or greater effects on decomposition than did elevated CO 2 and nitrogen addition. The identity of species lost also had a large effect on changes in productivity and decomposition, generating a wide range of plausible outcomes for extinction. Despite the need for more studies on interactive effects of diversity loss and environmental changes, our analyses clearly show that the ecosystem consequences of local species loss are as quantitatively significant as the direct effects of several global change stressors that have mobilized major international concern and remediation efforts 9 .