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The study of functional traits offers predictive power for community ecology. Particularly in cases where individual species are difficult to study, known properties of trait spectra, such as the leaf economics spectrum (LES), and trait–environment relationships can provide crucial generalizable information that can contribute to forecasts of distributional shifts in response to the abiotic effects of climate and land use changes.Vascular epiphytes have been proposed as indicators of environmental change, but we know little about the ecology of most species. Key functional trait assumptions are based on terrestrial plants; testing these in epiphytes verifies their universality and will inform applying functional traits in predicting epiphyte responses to climate and land use change.In this study, we use functional traits from 37 vascular epiphyte species from forests and shade coffee farms at two sites in northern Nicaragua. We compare correlations among traits and intraspecific trait variances with those of terrestrial plants and among epiphyte taxonomic groups. We also test trait responses to environmental differences between sites and land use types, and within zones of the tree.We find that epiphyte leaf traits fall towards the slower end of the LES, but with about one‐third lower leaf nitrogen per change in specific leaf area (SLA) relative to terrestrial herbaceous plants. Bromeliads show less relationship between these traits than other epiphyte groups and also deviate in other trait interrelationships, suggesting unique leaf construction.Trait–environment relationships varied most strongly along vertical gradients within trees, but some traits, including SLA and carbon isotope ratio, also responded to land use and site differences.We present evidence that trait relationships established for terrestrial plants appear to translate to epiphytes, but identify some possible caveats. Strong trait response to vertical gradients within trees suggests that within‐canopy shifts could provide resilience to climate and land use changes for some epiphyte species. [ABSTRACT FROM AUTHOR]

Premise: The distribution of genetic diversity on the landscape has critical ecological and evolutionary implications. This may be especially the case on a local scale for foundation plant species because they create and define ecological communities, contributing disproportionately to ecosystem function. Methods: We examined the distribution of genetic diversity and clones, which we defined first as unique multilocus genotypes (MLG), and then by grouping similar MLGs into multilocus lineages. We used 186 markers from inter‐simple sequence repeats (ISSR) across 358 ramets from 13 patches of the foundation grass Leymus chinensis. We examined the relationship between genetic and clonal diversities, their variation with patch size, and the effect of the number of markers used to evaluate genetic diversity and structure in this species. Results: Every ramet had a unique MLG. Almost all patches consisted of individuals belonging to a single multilocus lineages. We confirmed this with a clustering algorithm to group related genotypes. The predominance of a single lineage within each patch could be the result of the accumulation of somatic mutations, limited dispersal, some sexual reproduction with partners mainly restricted to the same patch, or a combination of all three. Conclusions: We found strong genetic structure among patches of L. chinensis. Consistent with previous work on the species, the clustering of similar genotypes within patches suggests that clonal reproduction combined with somatic mutation, limited dispersal, and some degree of sexual reproduction among neighbors causes individuals within a patch to be more closely related than among patches. [ABSTRACT FROM AUTHOR]

Summary: Vulnerability to xylem cavitation is a strong predictor of drought‐induced damage in forest communities. However, biotic features of the community itself can influence water availability at the individual tree‐level, thereby modifying patterns of drought damage.Using an experimental forest in Tasmania, Australia, we determined the vulnerability to cavitation (leaf P50) of four tree species and assessed the drought‐induced canopy damage of 2944 6‐yr‐old trees after an extreme natural drought episode. We examined how individual damage was related to their size and the density and species identity of neighbouring trees.The two co‐occurring dominant tree species, Eucalyptus delegatensis and Eucalyptus regnans, were the most vulnerable to drought‐induced xylem cavitation and both species suffered significantly greater damage than neighbouring, subdominant species Pomaderris apetala and Acacia dealbata. While the two eucalypts had similar leaf P50 values, E. delegatensis suffered significantly greater damage, which was strongly related to the density of neighbouring P. apetala. Damage in E. regnans was less impacted by neighbouring plants and smaller trees of both eucalypts sustained significantly more damage than larger trees.Our findings demonstrate that natural drought damage is influenced by individual plant physiology as well as the composition, physiology and density of the surrounding stand. [ABSTRACT FROM AUTHOR]