Ecosphere最新文献

{"title":"Early evidence for establishment of a Chinook salmon population in a restored watershed","authors":"Lauren G. Hitt,&nbsp;Malte Willmes,&nbsp;George Whitman,&nbsp;Mackenzie C. Miner,&nbsp;Carson Jeffres,&nbsp;Rachel C. Johnson,&nbsp;Dennis E. Cocherell,&nbsp;Nann A. Fangue,&nbsp;Andrew L. Rypel","doi":"10.1002/ecs2.70207","DOIUrl":"https://doi.org/10.1002/ecs2.70207","url":null,"abstract":"<p>As fish populations face compounding pressures under climate change, highly modified rivers are receiving increasing research and conservation attention as important sites for restoration. Across the North Pacific Ocean, Chinook salmon (<i>Oncorhynchus tshawytscha</i>) have experienced unprecedented declines and extirpations because of habitat loss and fragmentation and climate variability. Here, we studied a rare example of a novel salmon population developing in Putah Creek, California, a dam-controlled stream flowing through an area of intensive agriculture where salmon were unlikely to occur prior to the rehabilitation of a more natural flow regime. We used otoliths from adult Chinook salmon carcasses recovered from Putah Creek to determine river or hatchery of origin for five spawning year classes. Our results provide evidence of successful salmon reproduction, outmigration survival, and natal homing of individuals back to Putah Creek in recent years. Although hatchery-origin fish that strayed to Putah Creek to spawn dominated returns each year, this study documents life-cycle completion required for the potential development of a self-sustaining salmon population. This study demonstrates that targeted restoration and flow rehabilitation efforts can generate viable new salmon spawning habitat in dam-controlled river systems, which could help mitigate habitat lost to dams and developments. Further, successful anadromous life-cycle completion can occur in new spawning habitat within the first several generations, which will help inform efforts to restore or reintroduce salmon in other altered river systems.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70207","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632811","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":"Hantavirus in rodents in the United States: Temporal and spatial trends and report of new hosts","authors":"Francisca Astorga,&nbsp;Abdelghafar Alkishe,&nbsp;Paanwaris Paansri,&nbsp;Gabriel Mantilla,&nbsp;Luis E. Escobar","doi":"10.1002/ecs2.70209","DOIUrl":"https://doi.org/10.1002/ecs2.70209","url":null,"abstract":"<p>In North America, the rodent-borne hantavirus pulmonary syndrome is predominantly caused by the Sin Nombre virus, typically associated with the deer mouse <i>Peromyscus maniculatus</i>. Utilizing data from the National Ecological Observatory Network (NEON) hantavirus program, we assessed factors that may influence the spatial and temporal distribution of hantavirus in rodent populations across the United States. Between 2014 and 2019, the NEON hantavirus program conducted 104,379 small mammal captures and collected 14,004 blood samples from 49 species at 45 field sites. Our study identified 296 seropositive samples across 15 rodent species, including 8 <i>Peromyscus</i> species. We describe six new species with hantavirus seropositive samples not previously reported as hantavirus hosts. The highest number of seropositive samples was obtained from <i>Pe. maniculatus</i> (<i>n</i> = 116; 2.9% seroprevalence), followed by <i>Peromyscus leucopus</i> (<i>n</i> = 96; 2.8%) and <i>Microtus pennsylvanicus</i> (<i>n</i> = 33; 4.2%). Hantavirus seroprevalence showed an uneven spatial distribution, with the highest seroprevalence found in Virginia (7.8%, 99 seropositive samples), Colorado (5.7%, <i>n</i> = 37), and Texas (4.8%, <i>n</i> = 19). Hantavirus seropositive samples were obtained from 32 sites, 10 of which presented seropositive samples in species other than <i>Pe. maniculatus</i> or <i>Pe. leucopus</i>. Seroprevalence was inconsistent across years but showed intra-annual bimodal trends, and in <i>Pe. maniculatus</i> and <i>Pe. leucopus</i>, the number of captures correlated with seroprevalence in the following months. Seroprevalence was higher in adult males, with only one seropositive sample obtained from a juvenile <i>Peromyscus truei</i>. Higher body mass, presence of scrotal testes, and nonpregnant status were associated with higher seropositivity. The NEON dataset, derived from a multiyear and structured surveillance system, revealed the extensive distribution of hantavirus across broad taxonomic and environmental ranges. Future research should consider winter season surveillance and continued analyses of stored samples for a comprehensive spatiotemporal study of hantavirus circulation in wildlife. Global changes are expected to affect the dynamics of rodent populations by affecting their availability of resources and demography and, consequently, may modify transmission rates of rodent-borne zoonotic pathogens such as hantavirus. This study can be considered a baseline to assess hantavirus patterns across host taxa, geographies, and seasons in the United States.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70209","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632812","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":"Divergent drought responses in two cold desert shrublands","authors":"Kerry M. Byrne,&nbsp;Justin C. Luong,&nbsp;Kristen M. Kaczynski","doi":"10.1002/ecs2.70211","DOIUrl":"https://doi.org/10.1002/ecs2.70211","url":null,"abstract":"<p>The frequency and intensity of extreme droughts are projected to increase in the future, yet current research indicates that ecosystem sensitivity to extremes will vary. Despite hundreds of observational and experimental drought studies across ecosystems, the underlying mechanism explaining the inconsistent responses to drought remains poorly understood. Differences in the magnitude or duration of drought, land use history, existing plant communities, or unique site conditions might all influence the drought response of a site. Due to unresolved questions related to ecosystem sensitivity to drought, additional studies are needed to improve our predictions about the drought responses across ecosystems. Here, we minimized differences in drought intensity, climatic variation, and land use history by conducting a rainfall manipulation study in two adjacent (~60 m apart) plant communities with distinct dominant species (<i>Artemisia arbuscula</i> and <i>Artemisia cana</i>) in eastern Oregon, USA. We used rainfall shelters to create a 1-in-100-year drought at each site to understand how chronic (4-year) drought will impact common, but understudied sagebrush steppe plant communities. We found that above- and belowground net primary production at both sites was remarkably resistant to four years of drought. Interestingly, litter increased over time in drought plots at the more productive site, and we hypothesize that hydraulic lift and litter interacted to increase shallow soil water content under drought at that site. The site with harsher edaphic features and a soil duripan experienced fewer changes in plant community composition than the more productive site, potentially due to the presence of specialized plant species at the harsher site. Non-native plant cover increased (primarily from <i>Ventenata dubia</i>) and native forb cover and density decreased across our four sampling years. This suggests that management may be needed to conserve native forb diversity and limit species invasion, especially as the climate and historic fire regimes change.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70211","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632995","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":"Smart camera traps and computer vision improve detections of small fauna","authors":"Angela J. L. Pestell,&nbsp;Anthony R. Rendall,&nbsp;Robin D. Sinclair,&nbsp;Euan G. Ritchie,&nbsp;Duc T. Nguyen,&nbsp;Dean M. Corva,&nbsp;Anne C. Eichholtzer,&nbsp;Abbas Z. Kouzani,&nbsp;Don A. Driscoll","doi":"10.1002/ecs2.70220","DOIUrl":"https://doi.org/10.1002/ecs2.70220","url":null,"abstract":"<p>Limited data on species' distributions are common for small animals, impeding conservation and management. Small animals, especially ectothermic taxa, are often difficult to detect, and therefore require increased time and resources to survey effectively. The rise of conservation technology has enabled researchers to monitor animals in a range of ecosystems and for longer periods than traditional methods (e.g., live trapping), increasing the quality of data and the cost-effectiveness of wildlife monitoring practices. We used DeakinCams, custom-built smart camera traps, to address three aims: (1) To survey small animals, including ectotherms, and evaluate the performance of a customized computer vision object detector trained on the SAWIT dataset for automating object classification; (2) At the same field sites and using commercially available camera traps, we evaluated how well MegaDetector—a freely available object detection model—detected images containing animals; and (3) we evaluated the complementarity of these two different approaches to wildlife monitoring. We collected 85,870 videos from the DeakinCams and 50,888 images from the commercial cameras. For object detection with DeakinCams data, SAWIT yielded 98% Precision but 47% recall, and for species classification, SAWIT performance varied by taxa, with 0% Precision and Recall for birds and 26% Precision and 14% Recall for spiders. For object detections with camera trap images, MegaDetector returned 99% Precision and 98% Recall. We found that only the DeakinCams detected nocturnal ectotherms and invertebrates. Making use of more diverse datasets for training models as well as advances in machine learning will likely improve the performance of models like YOLO in novel environments. Our results support the need for continued cross-disciplinary collaboration to ensure that large environmental datasets are available to train and test existing and emerging machine learning algorithms.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70220","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632994","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":"Wayfinding, knowledge, perspective, and engagement: Preparing tribal liaisons for stewardship of Indigenous lands","authors":"David C. Mays,&nbsp;Timberley M. Roane,&nbsp;Rafael Moreno-Sanchez,&nbsp;Cynthia Rice,&nbsp;Jessica L. Romero,&nbsp;Christine Velez","doi":"10.1002/ecs2.70181","DOIUrl":"https://doi.org/10.1002/ecs2.70181","url":null,"abstract":"<p>Indigenous stewardship practices, deeply rooted in traditional values and knowledge, often differ from non-Indigenous management approaches. Bridging these differing practices and approaches requires professionals trained in both Indigenous and non-Indigenous cultures, knowledge, and practices. The Environmental Stewardship of Indigenous Lands (ESIL) certificate at the University of Colorado Denver aims to prepare students for such roles, particularly as tribal liaisons, who facilitate government-to-government relationships and consultations. In particular, the ESIL certificate combines academic coursework with workshops and internships that provide knowledge and skills critical for effective liaison work, such as understanding tribal governance, communication, conflict resolution, and traditional ecological knowledge (TEK). The motivation for this work is that the preparation of tribal liaisons in higher education institutions faces several challenges such as rigid disciplinary curricula and insufficient access to culturally relevant immersive experiences in Indigenous communities and organizations. ESIL addresses these challenges through its workshops and internships, which complement traditional coursework by providing culturally relevant learning opportunities. Workshops cover topics like tribal law, TEK, and Indigeneity, while internships offer hands-on experiences that bridge academic learning with real-world contexts and applications. This paper presents the experiences in creating and operating workshops and internships as part of the ESIL certificate program. Workshops and internships were created following the theory of culturally relevant pedagogy, and student feedback was collected following the Indigenous evaluation framework. Student feedback indicates that these activities complement students' education and training to become effective tribal liaisons by enhancing their wayfinding, knowledge acquisition, perspective taking, and engagement with Indigenous cultures, knowledge, and practice. The ESIL program's approach underscores the importance of culturally tailored education and strong partnerships with Indigenous professionals and communities to prepare the next generation of tribal liaisons.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70181","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143581906","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 dominant plant species and insects interactively shape plant community structure and an ecosystem function","authors":"Julia N. Eckberg,&nbsp;Akane Hubbard,&nbsp;Nathan J. Sanders","doi":"10.1002/ecs2.70201","DOIUrl":"https://doi.org/10.1002/ecs2.70201","url":null,"abstract":"<p>Dominant plants and insects both structure plant communities and determine key ecosystem functions. However, dominant plants and insects can have opposing effects on plant community structure and ecosystem function. Critically, few studies have assessed the combined effects of these two drivers of plant community structure and ecosystem function. In this study, we factorially manipulated the presence of the dominant plant species <i>Solidago canadensis</i> (Canada goldenrod) and insects in an old field to quantify their independent and interactive effects on the plant community. Overall, insect presence mediated the effects of <i>S. canadensis</i> removal on plant biomass and richness. Total plant biomass was ~32% lower following <i>S. canadensis</i> removal only when insects were present. In contrast, subdominant plant biomass was ~75% higher following <i>S. canadensis</i> removal, but only when insects were reduced. Subdominant species richness was ~37% higher following <i>S. canadensis</i> removal when insects were present, although the abundance of most subdominant species did not vary systematically with <i>S. canadensis</i> removal or insect reduction. Light availability was ~49% higher following <i>S. canadensis</i> removal, with no effect of insect presence on light availability. Our results emphasize the interactive role of dominant plants and insects in determining the diversity and biomass of plant communities.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70201","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143581873","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":"Habitat suitability of common leopard in northern Pakistan","authors":"Faraz Akrim,&nbsp;Kenneth F. Kellner,&nbsp;Tariq Mahmood,&nbsp;Muhammad Waseem,&nbsp;Imad-Ul-Din Zangi,&nbsp;Siddiqa Qasim,&nbsp;Asad Aslam,&nbsp;Shafqaat Ahmed Hashmi,&nbsp;Hammad Bin Shoukat,&nbsp;Muhammad Raqeeb,&nbsp;Jerrold L. Belant","doi":"10.1002/ecs2.70218","DOIUrl":"https://doi.org/10.1002/ecs2.70218","url":null,"abstract":"<p>Habitat fragmentation and loss are considered primary threats to common leopards (<i>Panthera pardus</i>) across their geographical range. We investigated anthropogenic and environmental factors influencing the habitat suitability of leopards in northern Pakistan using an ensemble model of direct and indirect leopard signs during 2014–2022. Using location data from 206 leopard sightings the ensemble model's performance was good (true skill statistic, TSS = 0.52). Habitat suitability was highest in forest cover and negatively related to the density of settlements and roads. Habitat suitability peaked at intermediate elevations (about 1000–2000 m). Based on the ensemble model, we estimated 4543 km² of leopard habitat in northern Pakistan, of which 3144 km² (69%) occurred in six contiguous patches of at least 58 km² (range = 65–951 km²), the minimum size to support one female leopard. There was one patch of leopard habitat at least 58 km² within a protected area, and overall, 36% of total protected areas were estimated as suitable. Our findings suggest that the current network of protected areas in northern Pakistan does not adequately represent suitable habitat for leopards; increasing forest cover and expanding the protected area network could improve leopard habitat suitability.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70218","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143581874","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":"High sensitivity of herbaceous legumes to freezing: Insights from a multiyear snow removal study","authors":"Samuel L. Rycroft,&nbsp;Hugh A. L. Henry","doi":"10.1002/ecs2.70219","DOIUrl":"https://doi.org/10.1002/ecs2.70219","url":null,"abstract":"<p>Reductions in snow cover resulting from winter climate change are anticipated to increase the intensity of freezing exposure for overwintering herbaceous plants in many northern temperate regions. We examined whether herbaceous legumes, a key functional group responsible for increasing soil nitrogen inputs, are more sensitive to freezing than nonleguminous plants in northern temperate plant communities. We conducted snow removal experiments for three years in three herbaceous plant communities (a fallow area, an old field and a restored prairie) and recorded plant cover and biomass responses. For all three years, there were substantial decreases in legume biomass in response to snow removal for the fallow area (reductions of 70%, 90% and 50%; primarily <i>Melilotus albus</i> and <i>M. officinalis</i>) and old field (reductions of 50%, 60% and 50%; primarily <i>Trifolium pratense</i> and <i>Lotus corniculatus</i>), whereas there were no consistent significant reductions in biomass across years for the other herbaceous functional groups (graminoids and nonleguminous forbs). In contrast, in the restored prairie, dominated by the native legume <i>Desmodium canadense</i>, there were no consistent snow removal effects on the biomass of legumes or any other functional groups across years, although snow removal did reduce the percent cover of this species early in the growing season. Our results suggest that increased soil freezing via reductions in snow cover can have a stronger negative effect on some legumes than on other functional groups in northern temperate herbaceous plant communities, potentially reducing soil nitrogen inputs.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70219","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143581907","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":"Assessing the effects of climate and visitor use on amphibian occupancy in a protected landscape with long-term data","authors":"Amanda M. Kissel,&nbsp;Mary Kay Watry,&nbsp;Evan Bredeweg,&nbsp;Erin Muths","doi":"10.1002/ecs2.70210","DOIUrl":"https://doi.org/10.1002/ecs2.70210","url":null,"abstract":"<p>Determining where animals are, and if they are persisting across protected landscapes, is necessary to implement appropriate management and conservation actions. For long-lived animals and those with boom-and-bust life histories, perspective across time contributes to discerning temporal trends in occupancy and persistence, and potentially in identifying mechanisms affecting those parameters. Long-term data are particularly useful in protected areas to quantify indicators of change that may be less obvious or occur more slowly. We used long-term amphibian data from Rocky Mountain National Park (RMNP) in a Bayesian occupancy modeling framework to estimate changes in occupancy, colonization, and persistence of amphibians over three decades and to explore the effects of climate, landscape change, and visitor use as mechanisms behind observed changes. Our results indicate that colonization and persistence are low and/or declining for <i>Pseudacris maculata</i>, <i>Lithobates sylvaticus</i>, and <i>Ambystoma mavortium</i>, and that occupied catchments are increasingly isolated. We found visitor use to have a consistently negative effect on occupancy and persistence of amphibians in RMNP, and that all species are more likely to occupy catchments with more complex habitat and a higher proportion of wetlands. While these results are sobering, they also provide a way forward where mitigation efforts can target identified drivers of change.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70210","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143581872","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":"Elevated CO2 and drought modify plant–plant and plant–mycorrhizal interactions in two codominant grasses","authors":"Smriti Pehim Limbu,&nbsp;Meghan L. Avolio","doi":"10.1002/ecs2.70198","DOIUrl":"https://doi.org/10.1002/ecs2.70198","url":null,"abstract":"<p>Plant–plant interactions play a critical role in shaping plant communities and influencing ecosystem services. However, how these interactions shift between positive (facilitation) and negative (competition) in response to environmental factors, including changes in symbiotic relationships with arbuscular mycorrhizal fungi (AMF), remains less understood. To address this knowledge gap, we conducted an experiment investigating the plant–plant interactions and AMF root colonization of two codominant grasses of tallgrass prairie, <i>Andropogon gerardii</i> and <i>Sorghastrum nutans</i>. We established three neighbor treatments (no neighbor, interspecific, and intraspecific interactions), and exposed the grasses to a combination of water and CO₂ treatments: drought with ambient CO₂, well-watered with ambient CO₂, drought with elevated CO₂, and well-watered with elevated CO₂. We hypothesized that elevated CO₂ would ameliorate the negative effect of drought on biomass and AMF root colonization in these grasses, and that competition would be most prominent under less stressful conditions (well-watered with ambient or elevated CO₂), decreasing as stress increased (drought with ambient CO₂), eventually leading to facilitation under more stressful conditions. Our findings demonstrated that elevated CO₂ ameliorated the negative effects of drought on the aboveground biomass of both grasses. Additionally, drought with ambient CO₂ treatment resulted in competition between plant individuals, which decreased as stress levels increased. Facilitation was observed under the least stressful condition (well-watered with elevated CO₂) for belowground biomass. Interestingly, AMF root colonization was higher under drought with ambient CO₂ treatment and decreased under drought with elevated CO₂ treatment in the presence of a neighbor, suggesting a stress-dependent response in AMF colonization. Our study revealed a shift in plant–plant and plant–AMF interactions driven by the combined effects of drought and elevated CO₂. These findings have important implications for understanding how codominant grasses and their symbiotic relationships with AMF may respond to changing climatic conditions in tallgrass prairie.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70198","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571403","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}