Replacements of small- by large-ranged species scale up to diversity loss in Europe’s temperate forest biome

Abstract

Biodiversity time series reveal global losses and accelerated redistributions of species, yet no net loss in local species richness. To better understand how these patterns are linked, we quantify how individual species trajectories scale up to diversity changes using data from 68 vegetation resurvey studies of seminatural forests in Europe. Herb-layer species with small geographic ranges are being replaced by more widely distributed species and our results suggest this is less due to species abundances than to species nitrogen (N) niches. N-deposition accelerates extinctions of small-ranged, N-efficient plants and colonization by broadly distributed, N-demanding plants including non-natives. Despite no net change in species richness at the spatial scale of a study site, losses of small-ranged species reduce biome-scale (gamma) diversity. These results provide one mechanism to explain the directional replacement of smallranged species within sites and thus patterns of biodiversity change across spatial scales.

Insect occurrence in agricultural land‐uses depends on realized niche and geographic range properties

“…The local niche filtering inferred here has consequences for how land use affects local richness and community composition in agroecosystems (Staude et al 2020). For example, the overall biodiversity differences between local assemblages (in different land uses) depend on environmental responses available within the source pool of species (i.e.…”

“…A wide‐ranged ‘winners’ versus narrow‐ranged ‘losers’ pattern is emerging as a consistent response of local assemblages to habitat change (Cleary and Mooers 2006, Scott et al 2006, Cofre et al 2007, Nowakowski et al 2017, Newbold et al 2018), but does not explain the mechanism whereby the winners win and losers lose (Staude et al 2020). Our results suggest that species’ realized niches are at least part of the answer: realized niches more strongly predict species’ presence–absences across land‐use classes than do their geographic ranges.…”

“…Our detectable fingerprint of realized niches is also supported in vertebrate taxa, where researchers have a much clearer idea of geographic ranges size of charismatic species (Frishkoff et al 2015, Williams et al 2019). Our study suggests understanding the factors contributing to geographic range sizes is key to unlock why species with smaller ranges are more sensitive to land use (Staude et al 2020). Although for many groups behavioural flexibility or diet breadth may also be important, realized niches should always be considered as a potential factor given the strong microclimate shifts with land‐use change.…”

“…An emerging paradigm is that species’ sensitivity and assemblage responses to land‐use change depend on species’ range size, ecological generality and niche limits (Williams and Newbold 2019, Staude et al 2020). One often‐supported prediction is that local communities in agroecosystems are largely comprised of species with wider geographic ranges (Cleary and Mooers 2006, Scott et al 2006, Cofre et al 2007, Nowakowski et al 2017, Newbold et al 2018).…”

“…morphology, behaviour, Verberk et al 2013, Wong et al 2018). However, why geographic range size predicts species’ land‐use response is often unclear because not all the many traits that relate to large range size also lead to resistance to land‐use change (Bartomeus et al 2013, Laube et al 2013, Newbold et al 2013, Rader et al 2014), and species’ niches may be a common driver of responses to environmental change and geographic range size (Staude et al 2020).…”