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Drees TH, Shea K. Climate warming increases insect-driven seed removal of two elaiosome-bearing invasive thistle species. Ecology 2024; 105:e4223. [PMID: 38038399 DOI: 10.1002/ecy.4223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 09/29/2023] [Accepted: 10/30/2023] [Indexed: 12/02/2023]
Abstract
Ants and other insects are often a source of localized secondary dispersal for wind-dispersed plants and thus play an important ecological role in their spatial dynamics, but there is limited information on how climate change will affect such dispersal processes. Here, we use field experiments to investigate how climate warming affects seed removal, as this initiation of movement represents the first step in insect-driven secondary dispersal. Our results indicate that for the invasive thistles Carduus nutans and Carduus acanthoides, increased growing temperature influences seed attractiveness to insect dispersers, with seeds from maternal plants grown at temperatures 0.6°C above ambient removed by insect dispersers at higher rates than their unwarmed counterparts. We also observe that seed elaiosomes in these two species play an important role in dispersal, as seeds without elaiosomes were significantly less likely to be removed over the same period. Significant interactions between elaiosome presence/absence and warming treatment were also observed, though only for C. acanthoides, with the boost in seed removal from warming dampened when the elaiosome was present compared to when it was absent. These findings provide evidence that climate warming may alter aspects of dispersal such as seed removal by secondary dispersers, with potential ramifications for dispersal in future climates since seed-bearing plants around the world may be subject to increased growing temperatures, and many of these plant species bear elaiosomes and experience seed dispersal by insects.
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Affiliation(s)
- Trevor H Drees
- Department of Biology and IGDP in Ecology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Katriona Shea
- Department of Biology and IGDP in Ecology, The Pennsylvania State University, University Park, Pennsylvania, USA
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2
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Drees TH, Shea K. Elevated temperatures shift flower head height distributions and seed dispersal patterns in two invasive thistle species. Ecology 2024; 105:e4201. [PMID: 37901946 DOI: 10.1002/ecy.4201] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 08/06/2023] [Accepted: 09/18/2023] [Indexed: 10/31/2023]
Abstract
Climate change may significantly alter how organisms disperse, with implications for population spread and species management. Wind-dispersed plants have emerged as a useful study system for investigating how climate change affects dispersal, although studies modeling wind dispersal often assume propagules are released from a single point on an individual. This simplifying assumption, while useful, may misestimate dispersal. Here, we investigate the effects of climate change on dispersal distances and spread rates, examining how these quantities shift when accounting for all points of seed release on an individual. Using the wind-dispersed invasive thistles Carduus nutans and Carduus acanthoides, we quantify temperature-driven shifts in the distribution of flower head heights using a passive warming field experiment, and estimate how these shifts affect dispersal using the Wald analytical long-distance (WALD) model; for C. nutans, we use existing demographic data to simulate how these shifts affect population spread rates. We also compare dispersal distances for both warmed and ambient temperature plants, considering the entire distribution of flower head heights versus the common assumption of point-source seed release at the maximum height. For experimentally grown individuals, an ~0.6°C higher growing temperature increased mean and maximum flower head height by 14.1 cm (15.0%) and 14.0 cm (13.2%), respectively, in C. nutans and by 21.2 cm (26.6%) and 31.8 cm (36.7%), respectively, in C. acanthoides. Seeds from warmed individuals were more likely to exceed a given dispersal distance than those from their unwarmed counterparts; warmed C. nutans and C. acanthoides seeds were on average 1.36 and 1.71 times as likely, respectively, to travel 10 m or more in dispersal simulations, with this disparity increasing at longer dispersal distances. For C. nutans, increased growing temperatures boosted simulated rates of population spread by 42.2%, while assuming dispersal from a maximum height point source rather than the true distribution of flower head heights increased simulated spread by up to 28.5%. Our results not only demonstrate faster population spread under increased temperatures, but also have substantial implications for modeling such spread, as the common simplifying assumption of dispersal from a single maximum height source may substantially overestimate spread rates.
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Affiliation(s)
- Trevor H Drees
- Department of Biology and IGDP in Ecology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Katriona Shea
- Department of Biology and IGDP in Ecology, The Pennsylvania State University, University Park, Pennsylvania, USA
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Jia T, Qi Y, Zhao H, Xian X, Li J, Huang H, Yu W, Liu WX. Estimation of climate-induced increased risk of Centaurea solstitialis L. invasion in China: An integrated study based on biomod2. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1113474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
IntroductionInvasive alien plants (IAPs) are major hazards to biodiversity, human health, and the agricultural economy. As one of the most aggressive species of IAPs, the distribution area of Centaurea solstitialis L. has increased exponentially in the past two years since its invasion into Xinjiang, China, in July 2014. Predicting the potential geographic distributions (PGDs) of C. solstitialis in China can provide theoretical support for preventing the continued spread of this weed.MethodsIn this study, based on 5,969 valid occurrence records of C. solstitialis and 33 environmental variables, we constructed an ensemble model to predict suitable habitats for C. solstitialis under climate change scenarios.ResultsOur results showed that the mean true skill statistic (TSS) values, area under the receiver operating characteristic (ROC) curve (AUC), and Cohen’s Kappa (KAPPA) for the ensemble model were 0.954, 0.996, and 0.943, respectively. The ensemble model yielded more precise predictions than those of the single model. Temperature seasonality (Bio4), minimum temperature of the coldest month (Bio6), precipitation of the driest month (Bio14), and human influence index (HII) have significantly disrupted the PGDs of C. solstitialis in China. The total (high) suitability habitat area of C. solstitialis in China was 275.91 × 104 (67.78 × 104) km2, accounting for 71.26 (7.06)% of China. The PGDs of C. solstitialis in China under the current climate were mainly in East China (Shandong, Jiangsu, Shanghai, Zhejiang, and Anhui), Central China (Henan, southwestern Shanxi, southern Shaanxi, southern Gansu, Hubei, Hunan, Jiangxi, Chongqing, and Guizhou), and South China (southern Tibet, eastern Sichuan, Yunnan, Guangxi, Guangdong, Fujian, and Taiwan). Under future climate scenarios, the total suitability habitat area for C. solstitialis will expand, whereas the high suitability habitat area will decrease.DiscussionThe main manifestation is that the shift of southeast China into a moderate suitability habitat, and the total suitability habitats will be extended to northwest China. More focus needs to be placed on preventing further spread of C. solstitialis in northwest China.
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Keller JA, Shea K. Pest management in future climates: Warming reduces physical weed management effectiveness. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2022; 32:e2633. [PMID: 35403285 PMCID: PMC9540271 DOI: 10.1002/eap.2633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/07/2021] [Accepted: 02/15/2022] [Indexed: 06/14/2023]
Abstract
Climate change alters many aspects of weed performance and may also alter the effectiveness of management practices to control pests. Despite this concern, entire categories of widely used management practices, such as physical control, remain understudied in this context. We conducted a field experiment growing the invasive pest musk thistle (Carduus nutans) at ambient and experimentally elevated temperatures. We tested mowing management strategies that varied in the timing of a single mowing event relative to thistles' stem elongation phenology and compared these with an unmowed control. Results from this experiment informed demographic models to project population growth rates for different warming/mowing scenarios. Compared to plants grown under ambient conditions, warmed thistles were more likely to survive the same mowing treatment, flowered earlier in the season, grew to taller heights, and produced more flowering capitula. Proportional reductions in plant height and capitulum production caused by mowing were smaller under warming. Warming did not change the relative ranking of mowing treatments; mowing late in the growing season (2 weeks after individuals first reached a height of 40 cm) was most effective at ambient temperatures and under warming. Warming caused significant increases in projected local population growth rate for all mowing treatments. For invasive musk thistle, warmed individuals outperformed individuals grown at ambient temperatures across all the mowing treatments we considered. Our results suggest that to achieve outcomes comparable to those attainable at today's temperatures, farmers will need to apply supplemental management, possibly including additional mowing effort or alternative practices such as chemical control. We recommend that scientists test management practices under experimental warming, where possible, and that managers monitor ongoing management to identify changes in effectiveness. Information about changes in managed weeds' mortality, fecundity, and phenology can then be used to make informed decisions in future climates.
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Affiliation(s)
- Joseph A. Keller
- Department of Biology and IGDP in EcologyThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Katriona Shea
- Department of Biology and IGDP in EcologyThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
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Mao R, Osunkoya OO, Campbell S, Adkins SW. Wind dispersal of seeds of
Parthenium hysterophorus
L. (Asteraceae) contributes to its steady invasion and spread. AUSTRAL ECOL 2022. [DOI: 10.1111/aec.13159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Runping Mao
- School of Agriculture and Food Sciences The University of Queensland Gatton Campus Queensland 4343 Australia
- Institute of Plant Protection Wuhan Institute of Landscape Architecture Wuhan Hubei China
| | - Olusegun O. Osunkoya
- Department of Agriculture and Fisheries Biosecurity Queensland, Ecosciences Precinct Brisbane Queensland Australia
| | - Shane Campbell
- School of Agriculture and Food Sciences The University of Queensland Gatton Campus Queensland 4343 Australia
| | - Stephen W. Adkins
- School of Agriculture and Food Sciences The University of Queensland Gatton Campus Queensland 4343 Australia
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6
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Maternal Environmental Light Conditions Affect the Morphological Allometry and Dispersal Potential of Acer palmatum Samaras. FORESTS 2021. [DOI: 10.3390/f12101313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Seed dispersal plays critical roles in determining species survival and community structures. Since the dispersal is biologically under maternal control, it is hypothesized that intraspecific variation of dispersal potential and associated traits of seeds (diaspores) should be influenced by maternal habitat quality. We tested this hypothesis by examining the effects of maternal environmental light condition on morphological traits and descending performance of nearly 1800 wind-dispersed samaras collected from maple species Acer palmatum. Results showed that samaras produced by trees from shaded microhabitats had greater dispersal potential, in terms of slower terminal velocity of descent, than those produced in open microhabitats. This advantage was largely attributed to morphological plasticity. On average, samaras produced in shaded microhabitats, as compared to those produced in open habitats, had lower wing loading by only reducing weight but not area. In allometric details, in the large size range, samaras from shaded microhabitats had larger areas than those from open microhabitats; in the small size range, samaras from shaded microhabitats had wider wings. These findings suggest that greater dispersal potential of samaras in response to stressful maternal light environment reflected an active maternal control through the morphological allometry of samaras.
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Beckman NG, Aslan CE, Rogers HS, Kogan O, Bronstein JL, Bullock JM, Hartig F, HilleRisLambers J, Zhou Y, Zurell D, Brodie JF, Bruna EM, Cantrell RS, Decker RR, Efiom E, Fricke EC, Gurski K, Hastings A, Johnson JS, Loiselle BA, Miriti MN, Neubert MG, Pejchar L, Poulsen JR, Pufal G, Razafindratsima OH, Sandor ME, Shea K, Schreiber S, Schupp EW, Snell RS, Strickland C, Zambrano J. Advancing an interdisciplinary framework to study seed dispersal ecology. AOB PLANTS 2020; 12:plz048. [PMID: 32346468 PMCID: PMC7179845 DOI: 10.1093/aobpla/plz048] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Accepted: 07/26/2019] [Indexed: 05/23/2023]
Abstract
Although dispersal is generally viewed as a crucial determinant for the fitness of any organism, our understanding of its role in the persistence and spread of plant populations remains incomplete. Generalizing and predicting dispersal processes are challenging due to context dependence of seed dispersal, environmental heterogeneity and interdependent processes occurring over multiple spatial and temporal scales. Current population models often use simple phenomenological descriptions of dispersal processes, limiting their ability to examine the role of population persistence and spread, especially under global change. To move seed dispersal ecology forward, we need to evaluate the impact of any single seed dispersal event within the full spatial and temporal context of a plant's life history and environmental variability that ultimately influences a population's ability to persist and spread. In this perspective, we provide guidance on integrating empirical and theoretical approaches that account for the context dependency of seed dispersal to improve our ability to generalize and predict the consequences of dispersal, and its anthropogenic alteration, across systems. We synthesize suitable theoretical frameworks for this work and discuss concepts, approaches and available data from diverse subdisciplines to help operationalize concepts, highlight recent breakthroughs across research areas and discuss ongoing challenges and open questions. We address knowledge gaps in the movement ecology of seeds and the integration of dispersal and demography that could benefit from such a synthesis. With an interdisciplinary perspective, we will be able to better understand how global change will impact seed dispersal processes, and potential cascading effects on plant population persistence, spread and biodiversity.
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Affiliation(s)
- Noelle G Beckman
- Department of Biology & Ecology Center, Utah State University, Logan, UT, USA
| | - Clare E Aslan
- Landscape Conservation Initiative, Northern Arizona University, Flagstaff, AZ, USA
| | - Haldre S Rogers
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, USA
| | - Oleg Kogan
- Physics Department, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Judith L Bronstein
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, USA
| | - James M Bullock
- Centre for Ecology and Hydrology, Benson Lane, Wallingford, UK
| | - Florian Hartig
- Theoretical Ecology, University of Regensburg, Regensburg, Germany
| | | | - Ying Zhou
- Department of Mathematics, Lafayette College, Easton, PA, USA
| | - Damaris Zurell
- Swiss Federal Research Institute WSL, Dept. Land Change Science, Birmensdorf, Switzerland
- Humboldt-University Berlin, Geography Dept., Berlin, Germany
| | - Jedediah F Brodie
- Division of Biological Sciences and Wildlife Biology Program, University of Montana, Missoula, MT, USA
| | - Emilio M Bruna
- Department of Wildlife Ecology & Conservation & Center for Latin American Studies, University of Florida, Gainesville, FL, USA
| | | | - Robin R Decker
- Department of Environmental Science and Policy, University of California, Davis, CA, USA
| | - Edu Efiom
- REDD+ Unit, Cross River State Forestry Commission, Calabar, Nigeria
- Biology Department, Lund University, Lund, Sweden
| | - Evan C Fricke
- National Socio-Environmental Synthesis Center, University of Maryland, Annapolis, MD, USA
| | - Katherine Gurski
- Department of Mathematics, Howard University, Washington, DC, USA
| | - Alan Hastings
- Department of Environmental Science and Policy, University of California, Davis, CA, USA
- Santa Fe Institute, Santa Fe, NM, USA
| | - Jeremy S Johnson
- School of Forestry, Northern Arizona University, Flagstaff, AZ, USA
| | - Bette A Loiselle
- Center for Latin American Studies and Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL, USA
| | - Maria N Miriti
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH, USA
| | - Michael G Neubert
- Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Liba Pejchar
- Department of Fish, Wildlife and Conservation Biology, Colorado State University, Fort Collins, CO, USA
| | - John R Poulsen
- Nicholas School of the Environment, Duke University, Durham, NC, USA
| | - Gesine Pufal
- Natur Conservation and Landscape Ecology, University of Freiburg Freiburg, Germany
| | | | - Manette E Sandor
- Landscape Conservation Initiative, Northern Arizona University, Flagstaff, AZ, USA
| | - Katriona Shea
- Department of Biology, The Pennsylvania State University, University Park, PA, USA
| | - Sebastian Schreiber
- Department of Evolution and Ecology and Center for Population Biology, University of California, Davis, CA, USA
| | - Eugene W Schupp
- Department of Wildland Resources & Ecology Center, Utah State University, Logan, UT, USA
| | - Rebecca S Snell
- Department of Environmental and Plant Biology, Ohio University, Athens, OH, USA
| | | | - Jenny Zambrano
- Department of Biology, University of Maryland, College Park, MD, USA
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Warming Increases Pollen Lipid Concentration in an Invasive Thistle, with Minor Effects on the Associated Floral-Visitor Community. INSECTS 2019; 11:insects11010020. [PMID: 31881659 PMCID: PMC7022432 DOI: 10.3390/insects11010020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 12/19/2019] [Accepted: 12/20/2019] [Indexed: 01/16/2023]
Abstract
Climate warming is likely to change the ways in which plants interact with their insect mutualists, for example through changes in phytochemistry. In particular, this may have implications for the ways in which we manage noxious weeds, which may spread more quickly if they experience stronger mutualistic interactions. We grew the invasive nodding thistle, Carduus nutans, in two experimental treatments in the field: either passively warmed with open top chambers or at ambient temperatures. We collected pollen from thistles in each treatment and analysed the total protein, lipid, and carbohydrate content. We observed no difference in the pollen protein or carbohydrate content, but the total lipid content of the pollen was significantly higher in warmed plants. We conducted a total of 12.75 h of observations of putatively mutualistic, flower-visiting insects. In addition, we spent 4.17 h collecting bees that visited thistle inflorescences in the treatments, allowing us to identify them to species. We found a significant increase in the abundance of flower-visiting insects in the observations, but not bee abundance in collections. In addition, there was no treatment effect on the number of flower-visiting morphotypes in the observations, or bee species richness in the collections. However, a nonparametric test did identify a significant effect of warming on the composition of flower-visiting morphotypes in observations and bee species in collections. Overall, the warming treatment significantly increased lipid content of the pollen, but had relatively weak effects on insect visitation patterns. However, these effects may be amplified at larger spatial and temporal scales or higher temperatures.
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9
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Rogers HS, Beckman NG, Hartig F, Johnson JS, Pufal G, Shea K, Zurell D, Bullock JM, Cantrell RS, Loiselle B, Pejchar L, Razafindratsima OH, Sandor ME, Schupp EW, Strickland WC, Zambrano J. The total dispersal kernel: a review and future directions. AOB PLANTS 2019; 11:plz042. [PMID: 31579119 PMCID: PMC6757349 DOI: 10.1093/aobpla/plz042] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Accepted: 07/18/2019] [Indexed: 05/22/2023]
Abstract
The distribution and abundance of plants across the world depends in part on their ability to move, which is commonly characterized by a dispersal kernel. For seeds, the total dispersal kernel (TDK) describes the combined influence of all primary, secondary and higher-order dispersal vectors on the overall dispersal kernel for a plant individual, population, species or community. Understanding the role of each vector within the TDK, and their combined influence on the TDK, is critically important for being able to predict plant responses to a changing biotic or abiotic environment. In addition, fully characterizing the TDK by including all vectors may affect predictions of population spread. Here, we review existing research on the TDK and discuss advances in empirical, conceptual modelling and statistical approaches that will facilitate broader application. The concept is simple, but few examples of well-characterized TDKs exist. We find that significant empirical challenges exist, as many studies do not account for all dispersal vectors (e.g. gravity, higher-order dispersal vectors), inadequately measure or estimate long-distance dispersal resulting from multiple vectors and/or neglect spatial heterogeneity and context dependence. Existing mathematical and conceptual modelling approaches and statistical methods allow fitting individual dispersal kernels and combining them to form a TDK; these will perform best if robust prior information is available. We recommend a modelling cycle to parameterize TDKs, where empirical data inform models, which in turn inform additional data collection. Finally, we recommend that the TDK concept be extended to account for not only where seeds land, but also how that location affects the likelihood of establishing and producing a reproductive adult, i.e. the total effective dispersal kernel.
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Affiliation(s)
- Haldre S Rogers
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, USA
- Corresponding author’s e-mail address:
| | - Noelle G Beckman
- Department of Biology and Ecology Center, Utah State University, Logan, UT, USA
| | - Florian Hartig
- Theoretical Ecology, Faculty of Biology and Preclinical Medicine, University of Regensburg, Regensburg, Germany
| | - Jeremy S Johnson
- School of Forestry, Northern Arizona University, Flagstaff, AZ, USA
| | - Gesine Pufal
- Department of Nature Conservation and Landscape Ecology, University of Freiburg, Freiburg, Germany
| | - Katriona Shea
- Department of Biology, The Pennsylvania State University, University Park, PA, USA
| | - Damaris Zurell
- Geography Department, Humboldt-University Berlin, Berlin, Germany
- Dynamic Macroecology, Department of Landscape Dynamics, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
| | - James M Bullock
- Centre for Ecology and Hydrology, Benson Lane, Wallingford, Oxfordshire, UK
| | | | - Bette Loiselle
- Department of Wildlife Ecology and Conservation & Center for Latin American Studies, University of Florida, Gainesville, FL, USA
| | - Liba Pejchar
- Department of Fish, Wildlife and Conservation Biology, Colorado State University, Fort Collins, CO, USA
| | | | - Manette E Sandor
- School of Earth Sciences and Environmental Sustainability, Northern Arizona University, Flagstaff, AZ, USA
| | - Eugene W Schupp
- Department of Wildland Resources and Ecology Center, Utah State University, Logan, UT, USA
| | - W Christopher Strickland
- Department of Mathematics and Department of Ecology & Evolutionary Biology, University of Tennessee, Knoxville, TN, USA
| | - Jenny Zambrano
- Department of Biology, University of Maryland, College Park, MD, USA
- School of Biological Sciences, Washington State University, Pullman WA, USA
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10
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Wind speed acceleration around a single low solid roughness in atmospheric boundary layer. Sci Rep 2019; 9:12002. [PMID: 31427684 PMCID: PMC6700104 DOI: 10.1038/s41598-019-48574-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 08/07/2019] [Indexed: 11/08/2022] Open
Abstract
Air flow around vegetation is crucial for particle transport (e.g., dust grains, seeds and pollens) in atmospheric boundary layer. However, wind acceleration around vegetation is still not well understood. In this work, air flow around a single low solid roughness element (representing a dense shrub patch or clump) in atmospheric boundary layer was numerically investigated, with emphasizing wind acceleration zone located at the two lateral sides. The maximum value of dimensionless horizontal wind speed as well as its location of occurrence and the geometrical morphology and area of wind acceleration zone were systematically studied. It reveals that they could alter significantly with the change of roughness basal shape. The maximum value of dimensionless resultant horizontal speed decreases monotonously with observation height, while the area of wind acceleration zone shows a non-linear response to observation height. The dependence of the maximum speed location on observation height is generally weak, but may vary with roughness basal shape. These findings could well explain the disagreement among previous field observations. We hope that these findings could be helpful to improve our understanding of aeolian transport in sparsely vegetated land in arid and semi-arid region, and wind dispersals of seeds and pollens from shrub vegetation.
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11
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Johnson JS, Cantrell RS, Cosner C, Hartig F, Hastings A, Rogers HS, Schupp EW, Shea K, Teller BJ, Yu X, Zurell D, Pufal G. Rapid changes in seed dispersal traits may modify plant responses to global change. AOB PLANTS 2019; 11:plz020. [PMID: 31198528 PMCID: PMC6548345 DOI: 10.1093/aobpla/plz020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 03/26/2019] [Indexed: 05/22/2023]
Abstract
When climatic or environmental conditions change, plant populations must either adapt to these new conditions, or track their niche via seed dispersal. Adaptation of plants to different abiotic environments has mostly been discussed with respect to physiological and demographic parameters that allow local persistence. However, rapid modifications in response to changing environmental conditions can also affect seed dispersal, both via plant traits and via their dispersal agents. Studying such changes empirically is challenging, due to the high variability in dispersal success, resulting from environmental heterogeneity, and substantial phenotypic variability of dispersal-related traits of seeds and their dispersers. The exact mechanisms that drive rapid changes are often not well understood, but the ecological implications of these processes are essential determinants of dispersal success, and deserve more attention from ecologists, especially in the context of adaptation to global change. We outline the evidence for rapid changes in seed dispersal traits by discussing variability due to plasticity or genetics broadly, and describe the specific traits and biological systems in which variability in dispersal is being studied, before discussing some of the potential underlying mechanisms. We then address future research needs and propose a simulation model that incorporates phenotypic plasticity in seed dispersal. We close with a call to action and encourage ecologists and biologist to embrace the challenge of better understanding rapid changes in seed dispersal and their consequences for the reaction of plant populations to global change.
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Affiliation(s)
- Jeremy S Johnson
- School of Forestry, Northern Arizona University, Flagstaff, AZ, USA
- Dorena Genetic Resource Center, USDA Forest Service, Cottage Grove, OR, USA
| | | | - Chris Cosner
- Department of Mathematics, The University of Miami, Coral Gables, FL, USA
| | - Florian Hartig
- Theoretical Ecology, University of Regensburg, Regensburg, Germany
| | - Alan Hastings
- Department of Environmental Science and Policy, University of California, Davis, CA, USA
| | - Haldre S Rogers
- Department of Ecology, Evolution, and Behavior, Iowa State University, Ames, IA, USA
| | - Eugene W Schupp
- Department of Wildland Resources & Ecology Center, Utah State University, Logan, UT, USA
| | - Katriona Shea
- Department of Biology, The Pennsylvania State University, University Park, PA, USA
| | - Brittany J Teller
- Department of Biology, The Pennsylvania State University, University Park, PA, USA
| | - Xiao Yu
- Department of Mathematics, The University of Miami, Coral Gables, FL, USA
| | - Damaris Zurell
- Department of Geography, Humboldt-University Berlin, Berlin, Germany
- Department of Land Change and Science, Swiss Federal Institute WSL, Birmensdorf, Switzerland
| | - Gesine Pufal
- Nature Conservation and Landscape Ecology, University of Freiburg, Freiburg, Germany
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12
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Yu H, Shen N, Yu S, Yu D, Liu C. Responses of the native species Sparganium angustifolium and the invasive species Egeria densa to warming and interspecific competition. PLoS One 2018; 13:e0199478. [PMID: 29924874 PMCID: PMC6010248 DOI: 10.1371/journal.pone.0199478] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 06/07/2018] [Indexed: 11/18/2022] Open
Abstract
Climate change, especially warming temperatures, may increase invasion and modify the ecological impacts of invasive species by enhancing their ability to compete. To test the effects of warming on invasive plants, a mesocosm experiment was conducted to study competition between the invasive plant Egeria densa and the native hygrophyte Sparganium angustifolium under simulated warming conditions in a greenhouse. These two species were grown in monoculture (no competitor control) or mixed culture (competitor control) for two months under different temperature conditions (warming treatment or no-warming treatment). In S. angustifolium, the higher temperatures led to a shorter root length and significantly increased the aboveground traits of ramets, the total biomass, and the RGR (relative growth rate) but had no effect on the aboveground traits of genets. Growth in mixed culture significantly decreased the S. angustifolium ramet height under warmer conditions and significantly reduced the ramet root length, ramet number, genet biomass, root-to-shoot ratio and RGR of S. angustifolium under natural temperature conditions. All the morphological, biomass and growth traits of E. densa except for the root-to-shoot ratio were significantly increased by the warmer temperatures and decreased by growth in mixed culture. The RCI and RII of E. densa in both the no-warming and warmer environments were two and three times greater than those of S. angustifolium, whereas the ACI values for the two species were similar. Thus, S. angustifolium was a better competitor than E. densa under both temperature conditions. These results suggest that although the superior competitive ability of native species can inhibit E. densa growth, the performance of this species will be enhanced under future climate warming in cold regions.
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Affiliation(s)
- Hongwei Yu
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, P.R. China
| | - Nan Shen
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, P.R. China
| | - Siqi Yu
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, P.R. China
| | - Dan Yu
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, P.R. China
| | - Chunhua Liu
- The National Field Station of Freshwater Ecosystem of Liangzi Lake, Department of Ecology, College of Life Sciences, Wuhan University, Wuhan, P.R. China
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Abstract
Applied ecologists often face uncertainty that hinders effective decision-making.Common traps that may catch the unwary are: ignoring uncertainty, acknowledging uncertainty but ploughing on, focussing on trivial uncertainties, believing your models, and unclear objectives.We integrate research insights and examples from a wide range of applied ecological fields to illustrate advances that are generally underused, but could facilitate ecologists' ability to plan and execute research to support management.Recommended approaches to avoid uncertainty traps are: embracing models, using decision theory, using models more effectively, thinking experimentally, and being realistic about uncertainty.Synthesis and applications. Applied ecologists can become more effective at informing management by using approaches that explicitly take account of uncertainty.
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Affiliation(s)
| | - K Shea
- Department of Biology, The Pennsylvania State University, USA
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14
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Heydel F, Tackenberg O. How are the phenologies of ripening and seed release affected by species' ecology and evolution? OIKOS 2016. [DOI: 10.1111/oik.03442] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Felix Heydel
- Ins. of Ecology, Evolution and Diversity; Goethe University; Max-von-Laue-Str. 13 DE-60438 Frankfurt am Main Germany
| | - Oliver Tackenberg
- Ins. of Ecology, Evolution and Diversity; Goethe University; Max-von-Laue-Str. 13 DE-60438 Frankfurt am Main Germany
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