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Abstract Explicit characterisation of the complexity of urban landscapes is critical for understanding patterns of biodiversity and for detecting the underlying social and ecological processes that shape them. Urban environments exhibit variable heterogeneity and connectivity, influenced by different historical contingencies, that affect community assembly across scales. The multidimensional nature of urban disturbance and co‐occurrence of multiple stressors can cause synergistic effects leading to nonlinear responses in populations and communities. Yet, current research design of urban ecology and evolutionary studies typically relies on simple representation of the parameter space that can be observed. Sampling approaches apply simple urban gradients such as linear transects in space or comparisons of urban sites across the urban mosaic accounting for a few variables. This rarely considers multiple dimensions and scales of biodiversity, and proves to be inadequate to explain observed patterns. We apply a multidimensional approach that integrates distinctive social, ecological and built characteristics of urban landscapes, representing variations along dimensions of heterogeneity, connectivity and historical contingency. Measuring species richness and beta diversity across 100 US metropolitan areas at the city and 1‐km scales, we show that distinctive signatures of urban biodiversity can result from interactions between socioecological heterogeneity and connectivity, mediated by historical contingency.
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Spatiotemporal dimensions of community assembly
Abstract Ecological communities are assembled through a series of multiple processes, including dispersal, abiotic and biotic filtering, and ecological drift. Although these assembly processes act in concert to structure local communities, their relative importance is considerably variable among study systems. While such contingency of community assembly has been widely appreciated, the empirical and theoretical evidence is scattered around in the literature, and few efforts have been made to synthesize it. In this mini‐review, we summarize the accumulated evidence of the context‐dependency of community assembly rules, to reach a rough generalization of the contingency. Specifically, we argue that spatial and temporal dimensions can serve as general axes that regulate the relative importance of assembly processes. To this end, we synthesize the current understanding of how the relative importance of multiple assembly processes changes with spatial scales and complexity, and with time in the long and short terms. This review concludes that spatial and temporal dimensions can be common currencies of community assembly rules that are shared across various systems.
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- Award ID(s):
- 2015634
- PAR ID:
- 10442942
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Population Ecology
- Volume:
- 65
- Issue:
- 1
- ISSN:
- 1438-3896
- Format(s):
- Medium: X Size: p. 5-16
- Size(s):
- p. 5-16
- Sponsoring Org:
- National Science Foundation
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