Data from: Climate, soil resources and microbial activity shape the distributions of mountain plants based on their functional traits

While soil ecosystems undergo important modi cations due to global change,
the e ect of soil properties on plant distributions is still poorly
understood. Plant growth is not only controlled by soil physico-chemistry
but also by microbial activities through the decomposition of organic
matter and the recycling of nutrients essential for plants. A growing body
of evidence also suggests that plant functional traits modulate spe- cies’
response to environmental gradients. However, no study has yet contrasted
the importance of soil physico-chemistry, microbial activities and climate
on plant species distributions, while accounting for how plant functional
traits can in uence species- speci c responses. Using hierarchical e ects
in a multi-species distribution model, we investigate how four functional
traits related to resource acquisition (plant height, leaf carbon to
nitro- gen ratio, leaf dry matter content and speci c leaf area) modulate
the response of 44 plant species to climatic variables, soil
physico-chemical properties and microbial 100 decomposition activity (i.e.
exoenzymatic activities) in the French Alps. Our hierarchical trait-based
model allowed to predict well 41 species according to the TSS statistic.
In addition to climate, the combination of soil C/N, as a measure of
organic matter quality, and exoenzymatic activity, as a measure of
microbial decom- position activity, strongly improved predictions of plant
distributions. Plant traits played an important role. In particular,
species with conservative traits performed bet- ter under limiting
nutrient conditions but were outcompeted by exploitative plants in more
favorable environments. We demonstrate tight associations between
microbial decomposition activity, plant functional traits associated to di
erent resource acquisition strategies and plant dis- tributions. is
highlights the importance of plant–soil linkages for mountain plant
distributions. ese results are crucial for biodiversity modelling in a
world where both climatic and soil systems are undergoing profound and
rapid transformations.