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1. Residential yard management and landscape cover affect urban bird community diversity across the continental USA

   https://doi.org/10.1002/eap.2455  

   Lerman, Susannah B.; Narango, Desirée L.; Avolio, Meghan L.; Bratt, Anika R.; Engebretson, Jesse M.; Groffman, Peter M.; Hall, Sharon J.; Heffernan, James B.; Hobbie, Sarah E.; Larson, Kelli L.; et al (September 2021, Ecological Applications)

   Brunton, Dianne (Ed.)

   Urbanization has a homogenizing effect on biodiversity and leads to communities with fewer native species and lower conservation value. However, few studies have explored whether or how land management by urban residents can ameliorate the deleterious effects of this homogenization on species composition. We tested the effects of local (land management) and neighborhood-scale (impervious surface and tree canopy cover) features on breeding bird diversity in six US metropolitan areas that differ in regional species pools and climate. We used a Bayesian multiregion community model to assess differences in species richness, functional guild richness, community turnover, population vulnerability, and public interest in each bird community in six land management types: two natural area park types (separate and adjacent to residential areas), two yard types with conservation features (wildlife-certified and water conservation) and two lawn-dominated yard types (high- and low-fertilizer application), and surrounding neighborhood-scale features. Species richness was higher in yards compared with parks; however, parks supported communities with high conservation scores while yards supported species of high public interest. Bird communities in all land management types were composed of primarily native species. Within yard types, species richness was strongly and positively associated with neighborhood-scale tree canopy cover and negatively associated with impervious surface. At a continental scale, community turnover between cities was lowest in yards and highest in parks. Within cities, however, turnover was lowest in high-fertilizer yards and highest in wildlife-certified yards and parks. Our results demonstrate that, across regions, preserving natural areas, minimizing impervious surfaces and increasing tree canopy are essential strategies to conserve regionally important species. However, yards, especially those managed for wildlife support diverse, heterogeneous bird communities with high public interest and potential to support species of conservation concern. Management approaches that include the preservation of protected parks, encourage wildlife-friendly yards and acknowledge how public interest in local birds can advance successful conservation in American residential landscapes. 

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2. Residential yard management and landscape cover affect urban bird community diversity across the continental USA

   Lerman, Susannah B.; Narango, Desiree. L.; Avolio, Meghan L.; Bratt, Anika R.; Engebretson, Jesse M.; Groffman, Peter M.; Hall, Sharon J.; Hefferenan, James B.; Hobbie, Sarah E.; Larson, Kelli L.; et al (January 2021, Ecological applications)

   Urbanization has a homogenizing effect on biodiversity and leads to communities with fewer native species and lower conservation value. However, few studies have explored whether or how land management by urban residents can ameliorate the deleterious effects of this homogenization on species composition. We tested the effects of local (land management) and neighborhood-scale (impervious surface and tree canopy cover) features on breeding bird diversity in six US metropolitan areas that differ in regional species pools and climate. We used a Bayesian multiregion community model to assess differences in species richness, functional guild richness, community turnover, population vulnerability, and public interest in each bird community in six land management types: two natural area park types (separate and adjacent to residential areas), two yard types with conservation features (wildlife-certified and water conservation) and two lawn-dominated yard types (high- and low-fertilizer application), and surrounding neighborhood-scale features. Species richness was higher in yards compared with parks; however, parks supported communities with high conservation scores while yards supported species of high public interest. Bird communities in all land management types were composed of primarily native species. Within yard types, species richness was strongly and positively associated with neighborhood-scale tree canopy cover and negatively associated with impervious surface. At a continental scale, community turnover between cities was lowest in yards and highest in parks. Within cities, however, turnover was lowest in high-fertilizer yards and highest in wildlife-certified yards and parks. Our results demonstrate that, across regions, preserving natural areas, minimizing impervious surfaces and increasing tree canopy are essential strategies to conserve regionally important species. However, yards, especially those managed for wildlife support diverse, heterogeneous bird communities with high public interest and potential to support species of conservation concern. Management approaches that include the preservation of protected parks, encourage wildlife-friendly yards and acknowledge how public interest in local birds can advance successful conservation in American residential landscapes. 

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3. Trees Inside and Outside of Forests in Guanacaste, Costa Rica: Comparisons Among Conservation Areas, Fencerows, and Urban Parks

   https://doi.org/10.1111/btp.70186  

   Powers, Jennifer S; Powers‐Tiffin, Finnegan; Choksi, Pooja; Fleischman, Forrest; Vargas_G, German; Becknell, Justin M; Hulshof, Catherine; O'Brien, Michael J; Aviles, Daniel Pérez; Arias, Damaris Pereira; et al (March 2026, Biotropica)

   ABSTRACT Many studies on the ecology of tropical trees occur in protected areas such as national parks. But we know little of the composition and structure of trees in areas outside protected forests, such as urban areas or along roads. Our goal was to contrast trees in three different land‐use types that represent an unmanaged or rural to urban gradient in Guanacaste, Costa Rica: forests inside conservation areas, fencerows, and urban parks. We hypothesized that: (1) trees in fencerows and urban parks have larger mean diameters, lower densities, and less plot‐level canopy cover and basal area; (2) tree diversity does not vary along rural to urban gradients, but trees in urban parks have comparatively more non‐native species and fewer native species. We measured and identified trees ≥ 7 cm diameter in replicated plots. Consistent with expectations, tree density and canopy cover were higher in conservation areas compared to fencerows or urban parks. However, basal area was lower in fencerows compared to both other land uses. Parks were dominated by large diameter trees, while conservation areas had smaller stems. When comparing land uses from the perspectives of biodiversity and provisioning ecosystem services such as edible fruit and shade, trees inside forests in conservation areas and outside forests in urban parks in Guanacaste provide complementary benefits to people and are not substitutable. We conclude that understanding trees both inside and outside of forests provides a broader context for studies situated in protected areas and an informative comparison for studies in urban areas. 

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4. From town to national park: Understanding the long-term effects of hunting and logging on tree communities in Central Africa

   https://doi.org/https://doi.org/10.1016/j.foreco.2021.119571  

   Maicher, Vincent; Clark, Connie J.; Harris, David J.; Medjibe, Vincent P.; Poulsen, John R. (January 2021, Forest ecology and management)

   null (Ed.)

   Anthropogenic disturbances are changing the structure and composition of tropical forests worldwide. Multiple disturbances often occur simultaneously in forests: for example, hunting and logging are within-forest disturbances that impact vast areas of seemingly intact rainforests. Despite recent work on the individual effects of these disturbances, our understanding of how they interact to influence tree communities is still limited. In northern Republic of Congo, we explored the effects of hunting and logging on tree communities. Over an 8-year period, we monitored 12,552 tree stems (≥ 10 cm diameter-at-breast height) spread over 30 1-ha plots along a gradient of human disturbance to compare the tree diversity between hunted and logged forest, once-logged forest, and protected forest free of both disturbances. Tree density, species richness, and community composition were affected by both hunting and logging. Forest close to human settlements was richer, more heterogenous, and more dynamic in species composition across censuses. In hunted and logged forest, fast-growing secondary species with low shade tolerance replaced old growth species. Comparatively, the once-logged forest had the greatest stem density and intermediate species richness with an increased density of shade-bearing species over time. Both tree species spatial turnover and tree recruitment were greatly affected by proximity to human settlements. A shift towards abiotically dispersed trees and increasing seed predation by rodents near villages can partly explain the differences in tree recruitment across the forest types. The combination of hunting and logging seems to have a greater impact on tree communities than either single disturbance, especially with nearness to villages. 

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5. Observed forest trait velocities have not kept pace with hydraulic stress from climate change

   https://doi.org/10.1111/gcb.16847  

   Quetin, G. R.; Anderegg, L. D.; Boving, I.; Anderegg, W. R.; Trugman, A. T. (September 2023, Global Change Biology)

   Abstract The extent to which future climate change will increase forest stress and the amount to which species and forest ecosystems can acclimate or adapt to increased stress is a major unknown. We used high‐resolution maps of hydraulic traits representing the diversity in tree drought tolerance across the United States, a hydraulically enabled tree model, and forest inventory observations of demographic shifts to quantify the ability for within‐species acclimation and between‐species range shifts to mediate climate stress. We found that forests are likely to experience increases in both acute and chronic hydraulic stress with climate change. Based on current species distributions, regional hydraulic trait diversity was sufficient to buffer against increased stress in 88% of forested areas. However, observed trait velocities in 81% of forested areas are not keeping up with the rate required to ameliorate projected future stress without leaf area acclimation. 

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