The influence of urban and agricultural landscape contexts on forest diversity and structure across ecoregions
Date
2025-02-25
Journal Title
Journal ISSN
Volume Title
Publisher
Ecosphere
Abstract
Forest patches in urban landscapes make outsized contributions to biodiversity, ecosystem function, and human health and well-being. However, urbanization can alter environmental conditions that underpin forest health. Most studies of forest health in urban landscapes have focused on few forest patches across a single metropolitan region, and synthesis is needed to understand broader patterns. We assessed variation among measures of forest health across land cover gradients and ecoregions by determining (1) whether the degree of urban, agricultural, and forested land surrounding a forest patch was reflected in differences in tree community composition, diversity, and structure and (2) whether these differences were consistent across ecoregions. We synthesized data from 17 observational studies (3334 plots) and remotely sensed land cover (1-km buffer) across four metropolitan regions (Baltimore–Washington DC, Chicago, New York City, and Philadelphia) spanning five ecoregions of the eastern deciduous forest of North America. Land cover surrounding forest patches differed among ecoregions, and forests were surrounded by heterogeneous land cover even in the most urbanized areas. Patterns of tree species composition and forest structure reflected landscape context. Forest patches surrounded by high canopy cover had greater or equal tree species diversity, density, basal area, and diversity of tree sizes relative to patches surrounded by highly agricultural or highly impervious landscapes. In contrast, there was little difference in structure and diversity between forests in highly agricultural and impervious settings. Tree species composition varied among ecoregions, yet tree community assemblages of forests in intensively urbanized areas were consistently distinct from those of forests in other contexts. Forest patches in the most urban and most agricultural landscapes shared predominantly native species communities and were characterized by low tree species diversity, basal area, and size class diversity, as well as high non-native tree abundance, highlighting commonalities among these intensive anthropogenic landscapes. These results point to both common challenges to forest health and common opportunities for forest stewardship in urban and agricultural landscapes.
Description
This article was originally published in Ecosphere. The version of record is available at: https://doi.org/10.1002/ecs2.70188.
© 2025 The Author(s). Ecosphere published by Wiley Periodicals LLC on behalf of The Ecological Society of America. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.
This is an open access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Keywords
data synthesis, ecoregion, landscape ecology, non-native species, plant community, urban forest, urbanization, urban–rural gradient, woodland
Citation
Schmit, John Paul, Lea R. Johnson, Matthew Baker, Lindsay Darling, Robert Fahey, Dexter H. Locke, Anita T. Morzillo, et al. 2025. “ The Influence of Urban and Agricultural Landscape Contexts on Forest Diversity and Structure across Ecoregions.” Ecosphere 16(2): e70188. https://doi.org/10.1002/ecs2.70188