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HIGHLIGHTS• Vegetation structure and composition were measured in four major green space types • Remnants and golf courses supported highest native plant richness • Residential neighborhoods and urban parks supported highest exotic plant richness • Residential neighborhoods lacked key habitat structures including old trees • Green spaces can achieve complex vegetation with both native and exotic vegetationThe ecological sustainability and function of urban landscapes is strongly influenced by the composition and structure of the local plant community. Taxonomic composition generally refers to the identity of the species comprising the community, while we define structure as the presence of multiple canopy layers, as well as stems of varying diameter and age. These aspects of urban vegetation significantly influence the ecology of cities, yet they are generally poorly quantified across the range of natural and constructed plant communities present in urban landscapes. We quantified vegetation composition and structure to (i) simultaneously assess their variation across four green spaces types (golf courses, public parks, residential neighborhoods, and patches of remnant vegetation) in Melbourne, Australia, and (ii) investigate the relationship between vegetation composition and structure within these green spaces. The four green space types supported distinctly different plant communities. Vegetation composition in the residential neighborhoods differed significantly from the others (p < 0.05), largely due to the increased richness of shrubs and cultivated plants, and the reduced presence of large trees. Residential neighborhoods had the highest plant species richness, although a large proportion of these species occurred infrequently. The structural complexity of understorey vegetation (calculated as % volume occupied) below 0.5 m was highest in remnant patches followed by golf courses, public parks, and residential neighborhoods. The structural complexity of understorey vegetation in remnant vegetation patches was very similar to that of golf courses even though some of the latter were dominated by exotic plant species. Variation in the composition and structure of urban vegetation might have great implications for Threlfall et al.Vegetation across Urban Green Spaces the retention of faunal diversity within cities because different taxa have specific habitat requirements. Hence, further understanding of variations in the composition and structure of both natural and constructed plant communities in cities will greatly improve our ability to create urban landscapes that enhance both plant and animal biodiversity.

Drought is expected to increase in frequency and severity in many regions in the future, so it is important to improve our understanding of how drought affects plant functional traits and ecological interactions. Imposing experimental water deficits is key to gaining this understanding, but has been hindered by logistic difficulties in maintaining consistently low water availability for plants. Here, we describe a simple method for applying soil water deficits to potted plants in glasshouse experiments. We modified an existing method (the "Snow and Tingey system") in order to apply a gradual, moderate water deficit to 50 plant species of different life forms (grasses, vines, shrubs, trees). The method requires less maintenance and manual handling compared to other water deficit methods, so it can be used for extended periods of time and is relatively inexpensive to implement. With only a few modifications, it is possible to easily establish and maintain soil water deficits of differing intensity and duration, as well as to incorporate interacting stress factors. We tested this method by measuring physiological responses to an applied water deficit in a subset of 11 tree/shrub species with a wide range of drought tolerances and water-use strategies. For this subgroup of species, stomatal conductance was 2-17 times lower in droughted plants than controls, although only half of the species (5 out of 11) experienced midday leaf water potentials that exceeded their turgor loss (i.e., wilting) point. Leaf temperatures were up to 8°C higher in droughted plants than controls, indicating that droughted plants are at greater risk of thermal damage, relative to unstressed plants. The largest leaf temperature differences (between droughted and well-watered plants) were in species with high rates of water loss. Rapid osmotic adjustment was observed in leaves of five species when drought stress was combined with an experimental heatwave. These results highlight the potential value of further ecological and physiological experiments utilizing this simple water deficit method to study plant responses to drought stress.

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a global database for metacommunity ecology, integrating species, traits, environment and space alienor Jeliazkov et al. #the use of functional information in the form of species traits plays an important role in explaining biodiversity patterns and responses to environmental changes. although relationships between species composition, their traits, and the environment have been extensively studied on a case-by-case basis, results are variable, and it remains unclear how generalizable these relationships are across ecosystems, taxa and spatial scales. to address this gap, we collated 80 datasets from trait-based studies into a global database for metaCommunity Ecology: Species, Traits, Environment and Space; "CEStES". Each dataset includes four matrices: species community abundances or presences/absences across multiple sites, species trait information, environmental variables and spatial coordinates of the sampling sites. the CEStES database is a live database: it will be maintained and expanded in the future as new datasets become available. By its harmonized structure, and the diversity of ecosystem types, taxonomic groups, and spatial scales it covers, the CEStES database provides an important opportunity for synthetic trait-based research in community ecology. Background & SummaryA major challenge in ecology is to understand the processes underlying community assembly and biodiversity patterns across space 1,2 . Over the three last decades, trait-based research, by taking up this challenge, has drawn increasing interest 3 , in particular with the aim of predicting biodiversity response to environment. In community ecology, it has been equated to the 'Holy Grail' that would allow ecologists to approach the potential processes underlying metacommunity patterns 4-7 . In macroecology, it is common to study biodiversity variation through its taxonomic and functional facets along gradients of environmental drivers 8-10 . In biodiversity-ecosystem functioning research, trait-based diversity measures complement taxonomic ones to predict ecosystem functions 11 offering early-warning signs of ecosystem perturbation 12 .The topic of Trait-Environment Relationships (TER) has been extensively studied across the globe and across the tree of life. However, each study deals with a specific system, taxonomic group, and geographic region and uses different methods to assess the relationship between species traits and the environment. As a consequence, we do not know how generalizable apparent relationships are, nor how they vary across ecosystems, realms, and taxonomic groups. In addition, while there is an emerging synthesis about the role of traits for terrestrial plant communities 13,14 , we know much less about other groups and ecosystem types.To address these gaps, we introduce the CESTES database -a global database for metaCommunity Ecology: Species, Traits, Environment and Space. This database assembles 80 datasets from studies that analysed empirical multivariate trait-environment relationships between 1996 (the first...