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Understanding the spatial scaling of population stability is critical for informing conservation strategies. A recently proposed metric for quantifying how population stability varies across scales is the invariability–area relationship (IAR), but the underlying drivers shaping IARs remain unclear. Using 15‐year records of 249 bird species in 1035 survey transects in North America, we derived the IAR for each species by calculating population temporal invariability at different spatial scales (i.e., number of routes) and investigated how species IARs were influenced by functional traits and environmental factors. We found that species with faster life history traits and reduced flight efficiency had higher IAR intercepts (i.e., locally more stable), whereas migratory species exhibited higher IAR slopes (i.e., a faster gain of stability with increasing spatial scale). In addition, spatial correlation in temperature and vegetation structure synchronized bird population dynamics over space and thus decreased IAR slopes. By demonstrating the joint influence of functional traits and environmental factors on bird population stability across scales, our results highlight the need for dynamic conservation strategies tailored to particular types of species in an era of global environmental changes. [ABSTRACT FROM AUTHOR]

The effects of dispersal on spatial synchrony and population variability have been well documented in theoretical research, and a growing number of empirical tests have been performed. Yet a synthesis is still lacking. Here, we conducted a meta-analysis of relevant experiments and examined how dispersal affected spatial synchrony and temporal population variability across scales. Our analyses showed that dispersal generally promoted spatial synchrony, and such effects increased with dispersal rate and decreased with environmental correlation among patches. The synchronizing effect of dispersal, however, was detected only when spatial synchrony was measured using the correlation-based index, not when the covariance-based index was used. In contrast to theoretical predictions, the effect of dispersal on local population variability was generally nonsignificant, except when environmental correlation among patches was negative and/or the experimental period was long. At the regional scale, while low dispersal stabilized metapopulation dynamics, high dispersal led to destabilization. Overall, the sign and strength of dispersal effects on spatial synchrony and population variability were modulated by taxa, environmental heterogeneity, type of perturbations, patch number, and experimental length. Our synthesis demonstrates that dispersal can affect the dynamics of spatially distributed populations, but its effects are context dependent on abiotic and biotic factors. [ABSTRACT FROM AUTHOR]

Three decades of research have demonstrated that biodiversity can promote the functioning of ecosystems. Yet, it is unclear whether the positive effects of biodiversity on ecosystem functioning will persist under various types of global environmental change drivers. We conducted a meta‐analysis of 46 factorial experiments manipulating both species richness and the environment to test how global change drivers (i.e. warming, drought, nutrient addition or CO2 enrichment) modulated the effect of biodiversity on multiple ecosystem functions across three taxonomic groups (microbes, phytoplankton and plants). We found that biodiversity increased ecosystem functioning in both ambient and manipulated environments, but often not to the same degree. In particular, biodiversity effects on ecosystem functioning were larger in stressful environments induced by global change drivers, indicating that high‐diversity communities were more resistant to environmental change. Using a subset of studies, we also found that the positive effects of biodiversity were mainly driven by interspecific complementarity and that these effects increased over time in both ambient and manipulated environments. Our findings support biodiversity conservation as a key strategy for sustainable ecosystem management in the face of global environmental change. [ABSTRACT FROM AUTHOR]

High reproductive and dispersal capacity allow invasive plant species to spread and establish, out-compete and occupy new niches. Sonneratia apetala , a species used in afforestation projects in southern China, was introduced from Bangladesh in 1985. This species has the capacity to colonize in mangrove mudflats and invade natural mangrove community of China. However, its effectiveness to do so may change with latitude. Aiming to provide reproduction evidence on S. apetala invasiveness from the perspective of fruit and seed properties, we conducted in situ observations of fruit and seed properties of 12 S. apetala populations across the latitudinal gradient from Haikou (19.60°N) to Quangang (25.25°N, current latitudinal limit for this species). Fruits per tree decreased with increasing latitude (R2 = 0.47; p < 0.0001); fruit weight (R2 = 0.28; p < 0.0001) and volume (R2 = 0.27; p < 0.0001) varied quadratically relative to latitude. However, seed quantity per fruit, weight and volume were not correlated with latitude. The relationship between fruit and several climatic factors showed that mean annual precipitation, mean annual low temperature and mean annual irradiance had significant effects on these properties. Fruit floating percentages suggested decreases with time but was markedly site specific. Accordingly, the dispersing potentials were high in low latitude regions with small and light fruits but with big quantity; while they were weak in high-latitude regions where medium size fruits might resist the cold in winter. The mid-latitude sites with large fruits and great germination percentage resulted in good performance and establishment, where the species invasiveness should be noted. • In situ observations were carried out on 12 S. apetala populations in China. • Fruit quantity per tree decreased with increasing latitude. • Fruit weight and volume showed hump-shaped changes along the latitude. • No latitudinal gradients were found for seed properties. • Solar radiation, precipitation and low temperature significantly affected fruit properties. [ABSTRACT FROM AUTHOR]

Multispecies tree planting has long been applied in forestry and landscape restoration in the hope of providing better timber production and ecosystem services; however, a systematic assessment of its effectiveness is lacking. We compiled a global dataset of matched single-species and multispecies plantations to evaluate the impact of multispecies planting on stand growth. Average tree height, diameter at breast height, and aboveground biomass were 5.4, 6.8, and 25.5% higher, respectively, in multispecies stands compared with single-species stands. These positive effects were mainly the result of interspecific complementarity and were modulated by differences in leaf morphology and leaf life span, stand age, planting density, and temperature. Our results have implications for designing afforestation and reforestation strategies and bridging experimental studies of biodiversity-ecosystem functioning relationships with real-world practices.