DOI: 10.6073/pasta/0e7977b6c267700482f70f13f799fe09
title: Shrub effects on seeding establishment, 2019 - 2020.

description: Plant communities in mountain ecosystems are particularly vulnerable
 due to amplified rates of warming (Pepin and Lundquist, 2008; Pepin
 et al., 2015) and declines in snowpack (Fyfe et al., 2017). As a
 result of these global change drivers, there is a widespread pattern
 of biotic shifts in the alpine (Bueno de Mesquita et al., 2018).
 However, it is unclear how important these biotic shifts will be in
 mediating the response of other species to global change. For
 example, the uphill movement and expansion of structure-forming
 species (e.g. trees, shrubs, cushion plants), can create small-scale
 variations in the conditions experienced by species (microclimates)
 through their effects on snow, wind, solar radiation, and soil
 properties (Holtmeier and Broll, 1992; Seastedt and Adams, 2001;
 Pistón et al., 2018; Chen et al., 2019). One such expanding
 structure-forming group of species are shrubs—the expansion and
 densification of shrubs is occurring in arctic and alpine zones
 across the globe (Myers-Smith et al., 2011; Formica et al., 2014;
 Elmendorf et al., 2012b, 2012a).Shrub microclimatic effects can
 alter fine-scale variability across the landscape, which may have
 important consequences for plant communities through increased
 heterogeneity and modified exposure. For instance, the microclimatic
 effects shrubs in the alpine may facilitate the establishment of
 subalpine species that need to migrate uphill to track their
 climatic niche (Akhalkatsi et al., 2006; Martínez, 2012; Cranston
 and Hermanutz, 2013).
 
 
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