Contributors
Previous research has shown that invertebrates are important contributors to the decomposition (natural breakdown) of dead plant matter. Ecologists Bin Tuo, Matty Berg and Hans Cornelissen now demonstrate that vertebrates, including mammals, birds, amphibians and fish, generally have a positive effect on the decomposition of plant matter as well by a variety of different pathways. The results are helpful to show the importance to society. We are not only losing many of our charismatic species, but also their important roles in the functioning of our ecosystems. The study is published in Nature Ecology & Evolution.
Pathways
The different pathways can be divided in indirect and direct ones. Indirect pathways include how vertebrates change their environment physically, thereby altering the microclimate for decomposition. They also create good conditions for decomposition by concentrating nutrients via urine and excrements. Direct positive effects of vertebrates on decomposition include animals eating litter or physically breaking it down. For instance, woodpeckers promote decomposition of deadwood by hacking into it to find beetle larvae. The latter pathway is quantified in an experimental field study by the researchers.
Forecasting climate change
The findings are strong enough to matter to global carbon cycling and should therefore be interesting for incorporating global carbon models that forecast climate change. Moreover, the study will stimulate new empirical studies in this emerging research field. This is important, since loss of vertebrates, "vertebrate defaunation" because of hunting, fishing, pollution, land conversion and climate change, is proceeding at an alarming rate worldwide.