Nonnative plant invasion increases urban vegetation structure and influences arthropod communities
Date
2023-08-07
Journal Title
Journal ISSN
Volume Title
Publisher
Diversity and Distributions
Abstract
Aim
Ecological theory and empirical evidence indicate that greater structural complexity and diversity in plant communities increases arthropod abundance and diversity. Nonnative plants are typically associated with low arthropod abundance and diversity due to lack of evolutionary history. However, nonnative plants increase the structural complexity of forests, as is common in urban forests. Therefore, urban forests are ideal ecosystems to determine whether structural complexity associated with nonnative plants will increase abundance and diversity of arthropods, as predicted by complexity literature, or whether structural complexity associated with nonnative plants will be depauperate of arthropods, as predicted by nonnative plant literature.
Location
We sampled 24 urban temperate deciduous and mixed forests in two cites, Raleigh, North Carolina and Newark, Delaware, in the eastern United States.
Methods
We quantified ground cover vegetation and shrub layer vegetation in each forest and created structural complexity metrics to represent total, nonnative and native understory vegetation structural complexity. We vacuum sampled arthropods from vegetation and quantified the abundance, biomass, richness and diversity of spiders and non-spider arthropods.
Results
Nonnative plants increase understory vegetation complexity in urban forests. In Raleigh and Newark, we found support for the hypotheses that dense vegetation will increase arthropod abundance and biomass, and against the hypothesis that nonnative vegetation will decrease arthropods. Urban forest arthropod abundance and biomass, but not diversity, increased with greater nonnative and native structural complexity.
Main Conclusions
Invaded urban forests may provide adequate food in the form of arthropod biomass to transfer energy to the next trophic level, but likely fail to provide ecological services and functions offered by diverse species, like forest specialists. Urban land managers should survey urban forests for nonnative and native plant communities and prioritize replacing dense nonnative plants with native species when allocating vegetation maintenance resources.
Description
This article was originally published in Diversity and Distributions. The version of record is available at: https://doi.org/10.1111/ddi.13755. © 2023 The Authors. Diversity and Distributions published by John Wiley & Sons Ltd.
Keywords
arthropod communities, insects, native, nonnative, spiders, understory structural diversity, urban forests
Citation
Mitchell, J. C., D’Amico, V. III, Trammell, T. L. E., & Frank, S. D. (2023). Nonnative plant invasion increases urban vegetation structure and influences arthropod communities. Diversity and Distributions, 29, 1263–1277. https://doi.org/10.1111/ddi.13755