Ecosphere最新文献

{"title":"Pseudogymnoascus destructans environmental reservoir decreases 11 years after an outbreak of white-nose syndrome","authors":"Karen J. Vanderwolf,&nbsp;Donald F. McAlpine,&nbsp;Caleb C. Ryan,&nbsp;Hugh G. Broders","doi":"10.1002/ecs2.70149","DOIUrl":"https://doi.org/10.1002/ecs2.70149","url":null,"abstract":"<p>White-nose syndrome is a skin disease of bats caused by the fungus <i>Pseudogymnoascus destructans</i> (<i>Pd</i>). <i>Pd</i> has devastated populations of some bat species in North America, where environmental reservoirs of the fungus are considered a threat to the persistence of bat populations. However, long-term patterns of <i>Pd</i> environmental persistence in North American hibernacula are unknown. We swabbed hibernacula walls 11 years after the invasion of <i>Pd</i> into Maritime Canada in 2011. This is the first study to examine the persistence of <i>Pd</i> in North American hibernacula &gt;7 years after the first documentation of <i>Pd</i> at a site. The proportion of hibernacula wall swabs with viable <i>Pd</i> decreased over time, with 40.6% of wall swabs positive (<i>n</i> = 32) in 2012, 35.0% (<i>n</i> = 40) in 2015, and 1.7% (<i>n</i> = 120) in 2022. In early winter 2022, 41.18% (<i>n</i> = 17) of bats (<i>Myotis lucifugus</i>, <i>M. septentrionalis</i>, and <i>Perimyotis subflavus</i>) were <i>Pd</i>-positive compared to 6.67% (<i>n</i> = 15) in late winter, a low prevalence and the opposite pattern compared to the first 4 years after <i>Pd</i> invasion to sites. Our results suggest that <i>Pd</i> loads in the environment naturally decrease to low or undetectable levels over time in our study region. Since attempts to reduce environmental reservoirs have a high likelihood of negative nontarget effects on hibernacula ecosystems, and a low likelihood of completely eradicating <i>Pd</i>, actions to reduce environmental reservoirs in hibernacula should consider deprioritizing sites where <i>Pd</i> has been present &gt;10 years. We urge the collection of further data across hibernacula sites with varied geochemistry, microclimates, organic matter availability, timing of <i>Pd</i> arrival, and surviving bat colony sizes. This will allow a more comprehensive assessment of this strategy.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70149","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143117282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Colorado Front Range grassland exhibits decreasing dominance of cheatgrass (Bromus tectorum) over time","authors":"Janet S. Prevéy,&nbsp;Timothy R. Seastedt","doi":"10.1002/ecs2.70154","DOIUrl":"https://doi.org/10.1002/ecs2.70154","url":null,"abstract":"<p>Causes, consequences, and potentials for recovery from invasions by the invasive annual grass, cheatgrass (<i>Bromus tectorum</i>), in western North America have been extensively documented. The vast majority of these studies have come from regions where yearly precipitation is dominated by “winter-wet” patterns, but this species has also demonstrated its ability to invade plant communities in “spring/summer-wet” areas as well. In grasslands of the Front Range of Colorado, a region experiencing a “spring/summer-wet” precipitation pattern, cheatgrass can exploit early-season soil moisture, but moderate rainfall continues into the growing season beyond the time of cheatgrass senescence. In this study, we measured how cheatgrass dominance changed over a 13-year interval in a disturbed meadow along the Front Range of Colorado with a “spring/summer-wet” precipitation pattern. Cheatgrass cover declined in absolute abundance by about 50% while total vegetation cover increased over this time period. The site was neither grazed nor burned during this interval. A “spring/summer-wet” precipitation pattern with high interannual variation in amounts occurred during the study, but no relationships between the seasonality or amounts of precipitation and the directional decline in cheatgrass abundance were observed. Rainout shelter manipulations showed that the seasonality of precipitation influenced cheatgrass abundance, with winter drought treatments reducing cheatgrass cover relative to plots that experienced summer drought treatments. The cheatgrass decline corresponded with a lesser decline in native grass cover and no change in native forb cover, while the abundance of non-native perennial grasses and forb species increased over the study interval. Although cheatgrass can invade communities across broad climatic gradients following disturbance, results from this study show that the persistence of cheatgrass within invaded areas may depend on the seasonality of precipitation and plant communities that vary across these gradients.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70154","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143115283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Migration strategy and constraint in migration behavior vary among shorebird species with different life histories","authors":"Sarah J. Clements,&nbsp;Jason P. Loghry,&nbsp;Jennifer A. Linscott,&nbsp;Jorge Ruiz,&nbsp;Joe C. Gunn,&nbsp;Juan G. Navedo,&nbsp;Nathan R. Senner,&nbsp;Bart M. Ballard,&nbsp;Mitch D. Weegman","doi":"10.1002/ecs2.70161","DOIUrl":"https://doi.org/10.1002/ecs2.70161","url":null,"abstract":"<p>Migration strategy is a key behavioral characteristic guiding how migratory species time their annual cycles and use habitat. Understanding variation in migration strategy within and among species and individuals can be useful for understanding how birds navigate energetic trade-offs and designing or modifying conservation plans meant to benefit multiple species and life histories. We compared migration strategies among three migratory shorebird species with variable life history traits and short, medium, and long migration distances, respectively: American avocets (<i>Recurvirostra americana</i>), black-bellied plovers (<i>Pluvialis squatarola</i>), and Hudsonian godwits (<i>Limosa haemastica</i>). Avocets (short distance) exhibited the most within-species variation in migration duration, proportion of migration time spent at stopovers, and stopover duration. Plovers (medium distance) and godwits (long distance) showed less variation in these metrics, but godwits showed the most variation in the number of stopovers used. There were significant differences among species in migration distance, number of stopovers used, proportion of time stopped over, departure and arrival dates, and migration duration, but not mean stopover duration. We also found that avocets spent more time stopped over relative to migration distance than plovers or godwits, indicating that avocets showed the most energy-minimizing strategy of the three species. Our findings set the stage for future work assessing the effects of climate change and land use on characteristics associated with different migration strategies for additional migratory species.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70161","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143115279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Benthic marine invertebrate herbivores diversify their algal diets in winter","authors":"R. M. Yoshioka,&nbsp;A. W. E. Galloway,&nbsp;J. B. Schram,&nbsp;L. E. Bell,&nbsp;K. J. Kroeker","doi":"10.1002/ecs2.70135","DOIUrl":"https://doi.org/10.1002/ecs2.70135","url":null,"abstract":"<p>Changes in the seasonal environment substantially influence organisms. Understanding how species respond to such changes, such as in their feeding interactions and physiology, is key to predicting their resilience to both seasonal and longer term climate changes. The Sitka Sound in Southeast Alaska, USA, is an attractive natural laboratory for studying change, as the marine environment experiences substantial seasonal fluctuations in parameters such as temperature, pH, and productivity between summer and winter. By sampling a suite of dominant macrophyte algae and their benthic herbivores in winter (January) and summer (July) 2019, we investigated how producers and their primary consumers may respond to seasonal change inferred through fatty acid trophic markers. We used a fatty acid logratio selection and analysis approach to ask the following: (1) Do fatty acid biomarkers for algae differ between seasons? (2) Do the same fatty acid biomarkers differ between seasons when applied to herbivores, with herbivore fatty acids tracking the presumed trophic resources? (3) Do fatty acid biomarkers for herbivores differ between seasons, when considered independently from algae? Comparing logratio sets selected each for the algae and the herbivore fatty acids, we found that algae fatty acids were different between our sampling seasons, but the algae-selected fatty acid logratios did not clearly separate most herbivores by season. In contrast, the herbivore-selected logratios strongly distinguished herbivore species between the January and June samplings. Further, dispersions of fatty acid logratios were greater within herbivore species in the winter than in the summer, potentially due to the utilization of more diverse resources when preferred algae are less abundant. In total, results suggest that herbivores are not simply tracking the seasonal fatty acid changes in the dominant algae as trophic resources; instead, herbivore fatty acid seasonal changes may occur largely through some other nonexclusive mechanisms, such as omnivory, reductions or shifts in dietary composition, and/or endogenous physiological responses. Thus, the benthic herbivores in our study appear not to be locked into their diets when faced with seasonal change and may use a range of strategies, including diet diversification, to cope with environmental variation.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70135","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143114817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resource selection and survival of plains sharp-tailed grouse at a wind energy facility","authors":"Carly S. Kelly,&nbsp;Chad W. LeBeau,&nbsp;Jeffrey L. Beck,&nbsp;Alex Solem,&nbsp;Hilary Morey,&nbsp;Kurt T. Smith","doi":"10.1002/ecs2.70164","DOIUrl":"https://doi.org/10.1002/ecs2.70164","url":null,"abstract":"<p>As the demand for wind energy development increases across much of the Great Plains region, there is a need to understand how this type of energy generation may impact wildlife. Due to their extensive range across areas with high wind resources, plains sharp-tailed grouse (<i>Tympanuchus phasianellus jamesi</i><i>Tympanuchus phasianellus jamesi</i>) represent a valuable species to evaluate how selection and survival are associated with existing wind energy infrastructure. We used spatial and demographic data collected from radio-marked female sharp-tailed grouse to evaluate resource selection (nest, brood-rearing, and breeding season) and survival (nest and female) near existing wind energy infrastructure during the April to August breeding season over a 3-year period from 2020 to 2022 in northeastern South Dakota, USA. We monitored 119 GPS-marked females captured at eight leks over the study period. We did not find evidence that females selected nest sites in relation to wind energy infrastructure but found that females with broods and females during the breeding season (April–August) avoided areas near high densities of wind turbines within 1.0 and 5.0 km of their home range, respectively. We found consistent selection for lower lengths of transmission lines across all life stages at the home range scale. We did not detect an effect of wind energy infrastructure on nest or female survival. Based on the results of our study, limiting the siting (the process of selecting the optimal location for a project and the associated features) of wind turbines within 5.0 km of sharp-tailed grouse breeding habitat may represent an important siting tool to minimize avoidance of otherwise suitable habitats.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70164","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143114816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Demographic rates and diversity vary with tree stature and ontogenetic stage in an African tropical rainforest","authors":"Moses B. Libalah,&nbsp;Sabrina E. Russo,&nbsp;George B. Chuyong,&nbsp;Duncan Thomas,&nbsp;David Kenfack","doi":"10.1002/ecs2.70144","DOIUrl":"https://doi.org/10.1002/ecs2.70144","url":null,"abstract":"<p>The vertical gradient of light in closed-canopy forests selects for trees with different adult statures, but our understanding of how stature affects forest diversity and demography is unclear. In a species-rich rainforest in Cameroon, we quantified the contributions of four growth forms of increasing adult stature (treelet, understory, canopy, emergent species) to forest structure and diversity, and investigated variation in life history trade-offs across growth forms. Treelets had the highest stem density, contributed the most to forest diversity, and diverged from larger statured species in terms of demographic trade-offs. Growth rates were slower for smaller statured than for larger statured species, and at the adult stage, treelets had significantly lower mortality than other growth forms. We observed significant interspecific trade-off relationships between staure and demographic rates that often differed between growth forms. Recruitment rate strongly declined with adult stature for all growth forms, but recruitment per reproductive adult declined only for emergents. While we observed a significant growth-mortality trade-off across all species, the trade-off was similar across growth forms. Smaller statured species in our study are not light-demanding but rather treelet and understory species that live entirely in the shaded understory. Differences in how historical biogeography has shaped species pools may ultimately cause variation in how adult stature contributes to tropical forest diversity.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70144","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143114815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A long-term study on food choices and nutritional goals of a leaf-eating primate","authors":"Patrick Lauer,&nbsp;Colin A. Chapman,&nbsp;Patrick Omeja,&nbsp;Jessica M. Rothman,&nbsp;Urs Kalbitzer","doi":"10.1002/ecs2.70162","DOIUrl":"https://doi.org/10.1002/ecs2.70162","url":null,"abstract":"<p>Efficient foraging plays a critical role in fitness, yet food choices and underlying nutritional goals vary among animals. To understand those choices and therefore the importance of different food resources, many studies estimate food preferences by applying electivity indices that account for resource availabilities. However, the general applicability of electivity indices in biologically relevant foraging scenarios is unclear. Our major aims were to find effective methods to estimate animals' food choices and to investigate long-term food choices and underlying nutritional goals of the red colobus monkey (<i>Piliocolobus tephrosceles</i>) in Kibale National Park, Uganda, an endangered folivore. We used simulations of different foraging conditions to evaluate the applicability of electivity indices in biologically relevant scenarios to help interpret our results. Then, we used long-term data collected between 2006 and 2016 on the feeding behavior and ecology of red colobus to determine the consumption frequencies of different foods and their food preferences. Based on these results and nutritional concentrations of young leaves of frequently consumed tree species, we investigated the importance of the protein-to-fiber ratio in their diet. Our simulations highlight limitations of electivity indices in biologically relevant foraging scenarios. Further, red colobus clearly chose young leaves over other plant parts, and, considering species and plant part, red colobus fed on many different items, but few dominated their diet. The availability and spatial distribution varied across the most consumed foods, but red colobus preferences remained mostly stable over time. Protein-to-fiber ratio had no association with preference but with consumption frequencies of different young leaves. The limitations of electivity indices in different foraging conditions underline the importance of comparing food preferences with consumption frequencies to assess the importance of different food resources. Our results provide a robust understanding of the food choices and nutritional goals of a leaf-eating animal that can ultimately be used for implementing more effective conservation measures by directing habitat protection or restoration efforts toward these resources.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70162","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143114419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Landscape composition and orchard management effects on bat assemblages and bat foraging activity in apple crops","authors":"Marcos Miñarro,&nbsp;Daniel García","doi":"10.1002/ecs2.70140","DOIUrl":"https://doi.org/10.1002/ecs2.70140","url":null,"abstract":"<p>Bats are acknowledged as suppliers of essential ecosystem services such as insect pest control in agroecosystems. Little is known, however, on how bat assemblages respond to the gradients imposed by anthropogenic landscapes and farming practices and how these environmental effects translate into changes in bat foraging. In this study, we use cider apple crop in northern Spain as a model to address the filtering effects of landscape composition and orchard management on, simultaneously, quantitative and qualitative characteristics of bat local assemblages and their foraging activity. For that, we carried out acoustic monitoring of bats and sampled pest moth abundance across a wider range of apple orchards covering different landscape contexts and local management conditions. We found that bat assemblages markedly varied across orchards, according mostly to landscape composition gradients but with contrasting landscape effects on different assemblage characteristics. Namely, higher levels of rural urbanization and lower cover of seminatural woody habitats around orchards promoted bat total activity and the number of bat species/species complexes. However, this also altered bat assemblage composition, increasing dominance by the most abundant species, and decreased bat functional diversity. Additionally, a greater cover of apple tree canopy within the orchards decreased bat total activity. Landscape gradients led into predictable variations of bat foraging activity, suggesting a potential persistence of pest control services even in landscapes with limited seminatural habitat cover. The present study highlights the differential responses of bat assemblages to apple crop landscape and orchard-scale conditions, hindering the establishment of straightforward management guidelines. Further analysis on the relationship between bat assemblage characteristics and pest control is necessary to understand how ecosystem services can be promoted through management in the apple agroecosystem.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70140","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143113089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancing the understanding of coastal disturbances with a network-of-networks approach","authors":"Allison N. Myers-Pigg,&nbsp;Diana Moanga,&nbsp;Ben Bond-Lamberty,&nbsp;Nicholas D. Ward,&nbsp;J. Patrick Megonigal,&nbsp;Elliott White Jr,&nbsp;Vanessa L. Bailey,&nbsp;Matthew L. Kirwan","doi":"10.1002/ecs2.70156","DOIUrl":"https://doi.org/10.1002/ecs2.70156","url":null,"abstract":"<p>Coastal ecosystems are at the nexus of many high priority challenges in environmental sciences, including predicting the influences of compounding disturbances exacerbated by climate change on biogeochemical cycling. While research in coastal science is fundamentally transdisciplinary—as drivers of biogeochemical and ecological processes often span scientific and environmental domains—traditional place–based approaches are still often employed to understand coastal ecosystems. We argue that a macrosystems science perspective, including the integration across distributed research sites, is crucial to understand how compounding disturbances affect coastal ecosystems. We suggest that many grand challenge questions, such as advancing continental-scale process understanding of extreme events and global change, will only be addressed in coastal ecosystems using a network-of-networks approach. We identify specific ways that existing research efforts can maximize benefit across multiple interested parties, and where additional infrastructure investments might increase return-on-investment along the coast, using the coastal continental United States as a case study.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70156","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143113161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pawpaws prevent predictability: A locally dominant tree alters understory beta-diversity and community assembly","authors":"Anna C. Wassel,&nbsp;Jonathan A. Myers","doi":"10.1002/ecs2.70115","DOIUrl":"https://doi.org/10.1002/ecs2.70115","url":null,"abstract":"<p>While dominant species are known to be important in ecosystem functioning and community assembly, biodiversity responses to the presence of dominant species can be highly variable. Dominant species can increase the importance of deterministic community assembly by competitively excluding species in a consistent way across local communities, resulting in low site-to-site variation in community composition (beta-diversity) and nonrandom community structure. In contrast, dominant species could increase the importance of stochastic community assembly by reducing the total number of individuals in local communities (community size), resulting in high beta-diversity and more random community structure. We tested these hypotheses in a large, temperate oak-hickory forest plot containing a locally dominant tree species, pawpaw (<i>Asimina triloba</i>; Annonaceae), an understory tree species that occurs in dense, clonal patches in forests throughout the east-central United States. We determined how the presence of pawpaw influences local species diversity, community size, and beta-diversity by measuring the abundance of all vascular plant species in 1 × 1-m plots both inside and outside pawpaw patches. To test whether the presence of pawpaw influences local assembly processes, we compared observed patterns of beta-diversity inside and outside patches to a null model in which communities were assembled at random with respect to species identity. We found lower local species diversity, lower community size, and higher observed beta-diversity inside pawpaw patches than outside pawpaw patches. Moreover, standardized effect sizes of beta-diversity from the null model were lower inside pawpaw patches than outside pawpaw patches, indicating more random species composition inside pawpaw patches. Together these results suggest that pawpaw increases the importance of stochastic relative to deterministic community assembly at local scales, likely by decreasing overall numbers of individuals and increasing random local extinctions inside patches. Our findings provide insights into the ecological processes by which locally dominant tree species shape the assembly and diversity of understory plant communities at different spatial scales.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70115","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143113162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}