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Published on: July 30, 2019
Body size as a predictor of species loss effect on ecosystem functioning
Annie Séguin1, Éric Harvey2, Philippe Archambault1
1Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, Rimouski, Canada, G5L 3A1.
Abstract:
There is an urgent need to develop predictive indicators of the effect of species loss on ecosystem functioning. Body size is often considered as a good indicator because of its relationship to extinction risk and several functional traits. Here, we examined the predictive capacity of species body size in marine and freshwater multitrophic systems. We found a significant, but weak, effect of body size on functioning. The effect was much stronger when considering the effect of body size within trophic position levels. Compared to extinctions ordered by body size, random extinction sequences had lower multiple species loss effects on functioning. Our study is the first to show experimentally, in multitrophic systems, a more negative impact of ordered extinction sequences on ecosystem functioning than random losses. Our results suggest apparent ease in predicting species loss effect on functioning based on easily measured ecological traits that are body size and trophic position.
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