Editor's Choice SeptemberSubmitted by editor on 5 September 2017.
The forum by Flombaum and colleagues puts the role of sampling effects for productivity maximisation central when invasions come into play. To date, most insights into the relevance and importance of biodiversity for ecosystem functioning point at the primary importance of niche complementary effects. Under this mechanism, ecosystem functions like primary production increase with species richness because more species use more complementary resources and thus give rise to an overall larger yield. Such mechanisms are mainly derived from experimental work using ‘pristine’ synthetic communities. In reality–and unfortunately, however- many ecosystems are invaded by exotic species. Because these are generally fitter than native species, the authors expect an increased role of sampling effects as a driver of productivity in invaded ecosystems as exotic species increase in abundance because of their competitively superiority. The authors illustrate their perspective with data collected along a tree-species richness gradient of a natural mountain forest in Argentina.
Our second EC is the meta-analysis on the importance of non-consumptive predator effects by Amanda Buchanan and colleagues. Non-consumptive effects (NCE) comprise changes in prey behaviour or physiology in response to predator threat. It is known that they are common in arthropod communities where they can be as strong as consumptive effects. The authors compiled data from a total of 128 predator–prey interaction experiments, which explicitly examined non-consumptive effects. The authors found NCEs to negatively impact prey and behavioural ones to be stronger than physiological ones. They identify key gaps and recommend steps to move this field forward.
Dries Bonte, EiC