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Sample records for alien invasive slider

  1. Alien invasive slider turtle in unpredicted habitat: a matter of niche shift or of predictors studied?

    Directory of Open Access Journals (Sweden)

    Dennis Rödder

    Full Text Available BACKGROUND: Species Distribution Models (SDMs aim on the characterization of a species' ecological niche and project it into geographic space. The result is a map of the species' potential distribution, which is, for instance, helpful to predict the capability of alien invasive species. With regard to alien invasive species, recently several authors observed a mismatch between potential distributions of native and invasive ranges derived from SDMs and, as an explanation, ecological niche shift during biological invasion has been suggested. We studied the physiologically well known Slider turtle from North America which today is widely distributed over the globe and address the issue of ecological niche shift versus choice of ecological predictors used for model building, i.e., by deriving SDMs using multiple sets of climatic predictor. PRINCIPAL FINDINGS: In one SDM, predictors were used aiming to mirror the physiological limits of the Slider turtle. It was compared to numerous other models based on various sets of ecological predictors or predictors aiming at comprehensiveness. The SDM focusing on the study species' physiological limits depicts the target species' worldwide potential distribution better than any of the other approaches. CONCLUSION: These results suggest that a natural history-driven understanding is crucial in developing statistical models of ecological niches (as SDMs while "comprehensive" or "standard" sets of ecological predictors may be of limited use.

  2. Alien invasive slider turtle in unpredicted habitat: a matter of niche shift or of predictors studied?

    Science.gov (United States)

    Rödder, Dennis; Schmidtlein, Sebastian; Veith, Michael; Lötters, Stefan

    2009-11-24

    Species Distribution Models (SDMs) aim on the characterization of a species' ecological niche and project it into geographic space. The result is a map of the species' potential distribution, which is, for instance, helpful to predict the capability of alien invasive species. With regard to alien invasive species, recently several authors observed a mismatch between potential distributions of native and invasive ranges derived from SDMs and, as an explanation, ecological niche shift during biological invasion has been suggested. We studied the physiologically well known Slider turtle from North America which today is widely distributed over the globe and address the issue of ecological niche shift versus choice of ecological predictors used for model building, i.e., by deriving SDMs using multiple sets of climatic predictor. In one SDM, predictors were used aiming to mirror the physiological limits of the Slider turtle. It was compared to numerous other models based on various sets of ecological predictors or predictors aiming at comprehensiveness. The SDM focusing on the study species' physiological limits depicts the target species' worldwide potential distribution better than any of the other approaches. These results suggest that a natural history-driven understanding is crucial in developing statistical models of ecological niches (as SDMs) while "comprehensive" or "standard" sets of ecological predictors may be of limited use.

  3. Invasive alien birds in Denmark

    DEFF Research Database (Denmark)

    Fox, Anthony David; Heldbjerg, Henning; Nyegaard, Timme

    2015-01-01

    Avian Introduced Alien Species (IAS) constitute a threat to the integrity of native biodiversity, the economy and human health, so here we briefly review some of the problems posed by such species around the world in relation to such bird species in Denmark. A new European Union Regulation...... on Invasive Alien Species implemented in January 2015 establishes a framework for actions to combat alien species, which requires Member States to prevent the spread of alien species, provide early warning and rapid responses to their presence and management of established alien species where they occur. We...... show the importance of mechanisms such as DOF’s (Dansk Ornitologisk Forening, BirdLife Denmark) Atlas project, Common Bird Census (breeding and wintering species) and DOFbasen to contribute data on the current geographical and numerical distribution of the few serious alien avian species already...

  4. Invasive alien birds in Denmark

    DEFF Research Database (Denmark)

    Nyegaard, Timme; Heldbjerg, Henning; Fox, Anthony David

    Avian Introduced Alien Species (IAS) constitute a threat to the integrity of native biodiversity, the economy and human health, so here we briefly review some of the problems posed by such species around the world in relation to bird species in Denmark. A new European Union Regulation on Invasive...... Alien Species implemented in January 2015 requires a framework for actions to combat alien species, which requires Member States to prevent the spread of alien species, provide early warning and rapid responses to their presence and management of established alien species where they occur. We show...... the importance of mechanisms such as DOFs (Danish Ornithological Society, BirdLife Denmark) Atlas project, Common Bird Monitoring (breeding and wintering species) and DOFbasen to contribute data on the current geographical and numerical distribution of the few serious alien avian species already present...

  5. Alien plant invasions in European woodlands

    NARCIS (Netherlands)

    Wagner, Viktoria; Chytrý, Milan; Jiménez-Alfaro, Borja; Pergl, Jan; Hennekens, Stephan; Biurrun, Idoia; Knollová, Ilona; Berg, Christian; Vassilev, Kiril; Rodwell, John S.; Škvorc, Željko; Jandt, Ute; Ewald, Jörg; Jansen, Florian; Tsiripidis, Ioannis; Botta-Dukát, Zoltán; Casella, Laura; Attorre, Fabio; Rašomavičius, Valerijus; Ćušterevska, Renata; Schaminée, Joop H.J.; Brunet, Jörg; Lenoir, Jonathan; Svenning, Jens Christian; Kącki, Zygmunt; Petrášová-Šibíková, Mária; Šilc, Urban; García-Mijangos, Itziar; Campos, Juan Antonio; Fernández-González, Federico; Wohlgemuth, Thomas; Onyshchenko, Viktor; Pyšek, Petr

    2017-01-01

    Aim: Woodlands make up a third of European territory and carry out important ecosystem functions, yet a comprehensive overview of their invasion by alien plants has never been undertaken across this continent. Location: Europe. Methods: We extracted data from 251,740 vegetation plots stored in the

  6. Uprooting and burial of invasive alien plants

    DEFF Research Database (Denmark)

    Kollmann, Johannes Christian; Brink-Jensen, Kasper; Frandsen, Sally I.

    2011-01-01

    Invasive alien plants are a problem for conservation management, and control of these species can be combined with habitat restoration. Subsoil burial of uprooted plants is a new method of mechanical control, which might be suitable in disturbed habitats. The method was tested in Rosa rugosa...

  7. Invasive alien freshwater fishes in the Wilderness Lakes System, a ...

    African Journals Online (AJOL)

    Invasive alien freshwater fishes in the Wilderness Lakes System, a wetland of international importance in the Western Cape Province, South Africa. ... A total of 87 893 fish comprising 16 species were caught. In addition to confirming the ... Key words: freshwater fish, invasive alien fishes, estuary, RAMSAR site, diversity.

  8. Modelling Hotspots for Invasive Alien Plants in India.

    Science.gov (United States)

    Adhikari, Dibyendu; Tiwary, Raghuvar; Barik, Saroj Kanta

    2015-01-01

    Identification of invasion hotspots that support multiple invasive alien species (IAS) is a pre-requisite for control and management of invasion. However, till recently it remained a methodological challenge to precisely determine such invasive hotspots. We identified the hotspots of alien species invasion in India through Ecological Niche Modelling (ENM) using species occurrence data from the Global Biodiversity Information Facility (GBIF). The predicted area of invasion for selected species were classified into 4 categories based on number of model agreements for a region i.e. high, medium, low and very low. About 49% of the total geographical area of India was predicted to be prone to invasion at moderate to high levels of climatic suitability. The intersection of anthropogenic biomes and ecoregions with the regions of 'high' climatic suitability was classified as hotspot of alien plant invasion. Nineteen of 47 ecoregions of India, harboured such hotspots. Most ecologically sensitive regions of India, including the 'biodiversity hotspots' and coastal regions coincide with invasion hotspots, indicating their vulnerability to alien plant invasion. Besides demonstrating the usefulness of ENM and open source data for IAS management, the present study provides a knowledge base for guiding the formulation of an effective policy and management strategy for controlling the invasive alien species.

  9. Control techniques for invasive alien plants

    Directory of Open Access Journals (Sweden)

    Michele de Sá Dechoum

    2013-03-01

    Full Text Available Invasive alien species are recognized as a major threat to the conservation of biodiversity. These species should be managed based on local and regional environmental conditions. Control techniques were tested for ten invasive species in Santa Catarina State: the trees Casuarina equisetifolia, Hovenia dulcis, Psidium guajava, Syzygium cumini, and Terminalia catappa, and shrubs and herbs Rubus fruticosus, Furcraea foetida, Hedychium coronarium, Impatiens walleriana, and Tradescantia zebrina. Treatments applied for trees were cut stump, frill and girdling or ring-barking followed by herbicide application, while the other species were treated with foliar spray, application of herbicide on the root system, cut stump and herbicide injection. The active ingredients tested were Triclopyr, Glyphosate, and the combination of Triclopyr + Fluroxipyr in concentrations from 2 to 6%, according to the species. The cut stump method was efficient for all of the woody species, while ring-barking and frilling followed by herbicide application and basal bark application resulted in different levels of efficiency for the species tested. The most efficient method for herbs and shrubs was foliar spray, and the least efficient methods were cut stump and herbicide injection.

  10. Invasive alien organisms in South West Africa/Namibia

    CSIR Research Space (South Africa)

    Brown, CJ

    1985-01-01

    Full Text Available The greatest threat of invasion of alien species of plants and animals is posed by species which originate from similar arid habitats in other parts of the world. In general the smaller the number of individuals of an alien species introduced...

  11. The outcome of alien tree invasions in Puerto Rico

    Science.gov (United States)

    Ariel E. Lugo

    2004-01-01

    Invasive alien tree species in Puerto Rico often form monospecific stands on deforested lands that were previously used for agriculture and then abandoned. Most native pioneer species are incapable of colonizing these sites, and thus introduced species have little competition from native trees. Alien trees may dominate sites for 30 to 40 years, but by that time native...

  12. Mycorrhizal status helps explain invasion success of alien plant species.

    Science.gov (United States)

    Menzel, Andreas; Hempel, Stefan; Klotz, Stefan; Moora, Mari; Pyšek, Petr; Rillig, Matthias C; Zobel, Martin; Kühn, Ingolf

    2017-01-01

    It is still debated whether alien plants benefit from being mycorrhizal, or if engaging in the symbiosis constrains their establishment and spread in new regions. We analyzed the association between mycorrhizal status of alien plant species in Germany and their invasion success. We compared whether the representation of species with different mycorrhizal status (obligate, facultative, or non-mycorrhizal) differed at several stages of the invasion process. We used generalized linear models to explain the occupied geographical range of alien plants, incorporating interactions of mycorrhizal status with plant traits related to morphology, reproduction, and life-history. Non-naturalized aliens did not differ from naturalized aliens in the relative frequency of different mycorrhizal status categories. Mycorrhizal status significantly explained the occupied range of alien plants; with facultative mycorrhizal species inhabiting a larger range than non-mycorrhizal aliens and obligate mycorrhizal plant species taking an intermediate position. Aliens with storage organs, shoot metamorphoses, or specialized structures promoting vegetative dispersal occupied a larger range when being facultative mycorrhizal. We conclude that being mycorrhizal is important for the persistence of aliens in Germany and constitutes an advantage compared to being non-mycorrhizal. Being facultative mycorrhizal seems to be especially advantageous for successful spread, as the flexibility of this mycorrhizal status may enable plants to use a broader set of ecological strategies. © 2016 by the Ecological Society of America.

  13. Impacts of invasive alien plants on water quality, with particular ...

    African Journals Online (AJOL)

    We review the current state of knowledge of quantified impacts of invasive alien plants on water quality, with a focus on South Africa. In South Africa, over 200 introduced plant species are regarded as invasive. Many of these species are particularly prominent in riparian ecosystems and their spread results in native species ...

  14. The assessment of invasive alien plant species removal programs ...

    African Journals Online (AJOL)

    Yusuf Adam

    Abstract. The occupation of natural environments by invasive alien plant species (IAPs) are a growing threat to ecosystems. This has resulted in the creation of government-based initiatives to mitigate invasion, however, there has been little progress towards assessing these initiatives. Remote sensing is a commonly used ...

  15. The assessment of invasive alien plant species removal programs ...

    African Journals Online (AJOL)

    The occupation of natural environments by invasive alien plant species (IAPs) are a growing threat to ecosystems. This has resulted in the creation of government-based initiatives to mitigate invasion, however, there has been little progress towards assessing these initiatives. Remote sensing is a commonly used tool in the ...

  16. Status, Impact and Management of Invasive Alien Species in Tanzania

    African Journals Online (AJOL)

    Invasive alien species (IAS) are among the significant drivers of environmental change worldwide and important causes of biodiversity losses. They contribute to economic hardship and social instability, placing constraints on sustainable development, economic growth, and ecological problems in various parts of the world, ...

  17. Scientific challenges in the field of invasive alien plant management

    CSIR Research Space (South Africa)

    Van Wilgen, BW

    2004-01-01

    Full Text Available This article examines scientific challenges in the field of invasion alien plant management in South Africa. Overview of the Working for Water program, Issues of research funding, and Biological control research. It also includes some of the papers...

  18. Invasive alien predator causes rapid declines of native European ladybirds

    DEFF Research Database (Denmark)

    Roy, Helen E.; Adriaens, Tim; Isaac, Nick J.B.

    2012-01-01

    Aim Invasive alien species (IAS) are recognized as major drivers of biodiversity loss, but few causal relationships between IAS and species declines have been documented. In this study, we compare the distribution (Belgium and Britain) and abundance (Belgium, Britain and Switzerland) of formerly...

  19. Clearing a path towards effective alien invasive control: the legal ...

    African Journals Online (AJOL)

    Alien invasive plants pose significant ecological, social and economic challenges for South Africa. These species threaten South Africa's rich biodiversity, deplete our scarce water resources, reduce the agricultural potential of land, cause soil erosion and intensify flooding and fires. According to recent estimations, over ...

  20. The identification and remote detection of alien invasive plants in ...

    African Journals Online (AJOL)

    Kabir Peerbhay

    The identification and remote detection of alien invasive plants in commercial forests: An Overview. Kabir Peerbhay* Onisimo Mutanga and Riyad Ismail. University of KwaZulu-Natal, School of Agricultural, Earth and Environmental Sciences, Discipline of Geography,. P/Bag X01, Scottsville 3209, Pietermaritzburg, South ...

  1. First record of predation by the alien invasive freshwater fish ...

    African Journals Online (AJOL)

    First record of predation by the alien invasive freshwater fish Micropterus salmoides L. (Centrarchidae) on migrating estuarine fishes in South Africa. ... Estuarine fish species, Monodactylus falciformis, and two species of the family Mugilidae, Mugil cephalus and Myxus capensis, were the most common fish prey in both size ...

  2. Invasive alien woody plants of the northern Cape

    Directory of Open Access Journals (Sweden)

    L. Henderson

    1991-10-01

    Full Text Available The frequency and abundance of invasive alien woody plants were recorded along roadsides and at watercourse crossings in 31% (90/286 of the quarter degree squares in the study area. The survey yielded 23 species of which the most prominent invaders were Prosopis spp. The most prominent remaining species were: Opuntia ficus-indica, Nicotiana glauca and Melia azedarach. The greatest abundance and diversity of alien invader plants were recorded near human settlements. More than half of the total recorded species have invaded perennial riverbanks. The episodic Molopo and Kuruman Rivers have been invaded almost exclusively by  Prosopis spp., which in places have formed extensive stands.

  3. Alien plant invasions in European woodlands

    Czech Academy of Sciences Publication Activity Database

    Wagner, V.; Chytrý, M.; Jiménez-Alfaro, B.; Pergl, Jan; Hennekens, S. M.; Biurrun, I.; Knollová, I.; Berg, C.; Vassilev, K.; Rodwell, J. S.; Škvorc, Ž.; Jandt, U.; Ewald, J.; Jansen, F.; Tsiripidis, I.; Botta-Dukát, Z.; Casella, L.; Attorre, F.; Rašomavičius, V.; Ćušterevska, R.; Schaminée, J.H.J.; Brunet, J.; Lenoir, J.; Svenning, J.-C.; Kacki, Z.; Petrášová-Šibíková, M.; Šilc, U.; García-Mijangos, I.; Campos, J. A.; Fernández-González, F.; Wohlgemuth, T.; Onyshchenko, V.; Pyšek, Petr

    2017-01-01

    Roč. 23, č. 9 (2017), s. 969-981 ISSN 1366-9516 R&D Projects: GA ČR GB14-36079G Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : neophyte * non-native * invasive plants * EUNIS * forests Subject RIV: EH - Ecology, Behaviour OBOR OECD: Biodiversity conservation Impact factor: 4.391, year: 2016

  4. The changing role of ornamental horticulture in alien plant invasions.

    Science.gov (United States)

    van Kleunen, Mark; Essl, Franz; Pergl, Jan; Brundu, Giuseppe; Carboni, Marta; Dullinger, Stefan; Early, Regan; González-Moreno, Pablo; Groom, Quentin J; Hulme, Philip E; Kueffer, Christoph; Kühn, Ingolf; Máguas, Cristina; Maurel, Noëlie; Novoa, Ana; Parepa, Madalin; Pyšek, Petr; Seebens, Hanno; Tanner, Rob; Touza, Julia; Verbrugge, Laura; Weber, Ewald; Dawson, Wayne; Kreft, Holger; Weigelt, Patrick; Winter, Marten; Klonner, Günther; Talluto, Matthew V; Dehnen-Schmutz, Katharina

    2018-03-05

    The number of alien plants escaping from cultivation into native ecosystems is increasing steadily. We provide an overview of the historical, contemporary and potential future roles of ornamental horticulture in plant invasions. We show that currently at least 75% and 93% of the global naturalised alien flora is grown in domestic and botanical gardens, respectively. Species grown in gardens also have a larger naturalised range than those that are not. After the Middle Ages, particularly in the 18th and 19th centuries, a global trade network in plants emerged. Since then, cultivated alien species also started to appear in the wild more frequently than non-cultivated aliens globally, particularly during the 19th century. Horticulture still plays a prominent role in current plant introduction, and the monetary value of live-plant imports in different parts of the world is steadily increasing. Historically, botanical gardens - an important component of horticulture - played a major role in displaying, cultivating and distributing new plant discoveries. While the role of botanical gardens in the horticultural supply chain has declined, they are still a significant link, with one-third of institutions involved in retail-plant sales and horticultural research. However, botanical gardens have also become more dependent on commercial nurseries as plant sources, particularly in North America. Plants selected for ornamental purposes are not a random selection of the global flora, and some of the plant characteristics promoted through horticulture, such as fast growth, also promote invasion. Efforts to breed non-invasive plant cultivars are still rare. Socio-economical, technological, and environmental changes will lead to novel patterns of plant introductions and invasion opportunities for the species that are already cultivated. We describe the role that horticulture could play in mediating these changes. We identify current research challenges, and call for more

  5. The casual, naturalised and invasive alien flora of Zimbabwe based on herbarium and literature records

    Directory of Open Access Journals (Sweden)

    Alfred Maroyi

    2012-10-01

    Conservation implications: This research provides baseline information and historical invasion patterns of casual, naturalised and invasive alien flora in Zimbabwe. This inventory is a crucial starting point in trying to understand and initiate the management of biological invasions. This is also important for monitoring new introductions and management of existing alien plants in Zimbabwe.

  6. Invasive alien woody plants of the Orange Free State

    Directory of Open Access Journals (Sweden)

    L. Henderson

    1991-09-01

    Full Text Available The frequency and abundance of invasive alien woody plants were recorded along roadsides and at watercourse crossings in 66% (151/230 of the quarter degree squares in the study area. The survey yielded 64 species of which the most prominent (in order of prominence in streambank habitats were:  Salix babylonica, Populus x  canescens, Acacia dealbata and  Salix fragilis (fide R.D. Meikle pers. comm . The most prominent species (in order of prominence in roadside and veld habitats were:  Opunlia ficus-indica, Prunus persica, Eucalyptus spp..  Rosa eglanteria, Pyracantha angustifolia and Acacia dealbata.Little invasion was recorded for most of the province. The greatest intensity of invasion was recorded along the perennial rivers and rocky hillsides in the moist grassland of the eastern mountain region bordering on Lesotho and Natal.

  7. Comparative Functional Responses Predict the Invasiveness and Ecological Impacts of Alien Herbivorous Snails.

    Directory of Open Access Journals (Sweden)

    Meng Xu

    Full Text Available Understanding determinants of the invasiveness and ecological impacts of alien species is amongst the most sought-after and urgent research questions in ecology. Several studies have shown the value of comparing the functional responses (FRs of alien and native predators towards native prey, however, the technique is under-explored with herbivorous alien species and as a predictor of invasiveness as distinct from ecological impact. Here, in China, we conducted a mesocosm experiment to compare the FRs among three herbivorous snail species: the golden apple snail, Pomacea canaliculata, a highly invasive and high impact alien listed in "100 of the World's Worst Invasive Alien Species"; Planorbarius corneus, a non-invasive, low impact alien; and the Chinese native snail, Bellamya aeruginosa, when feeding on four locally occurring plant species. Further, by using a numerical response equation, we modelled the population dynamics of the snail consumers. For standard FR parameters, we found that the invasive and damaging alien snail had the highest "attack rates" a, shortest "handling times" h and also the highest estimated maximum feeding rates, 1/hT, whereas the native species had the lowest attack rates, longest handling times and lowest maximum feeding rates. The non-invasive, low impact alien species had consistently intermediate FR parameters. The invasive alien species had higher population growth potential than the native snail species, whilst that of the non-invasive alien species was intermediate. Thus, while the comparative FR approach has been proposed as a reliable method for predicting the ecological impacts of invasive predators, our results further suggest that comparative FRs could extend to predict the invasiveness and ecological impacts of alien herbivores and should be explored in other taxa and trophic groups to determine the general utility of the approach.

  8. Comparative Functional Responses Predict the Invasiveness and Ecological Impacts of Alien Herbivorous Snails

    Science.gov (United States)

    Xu, Meng; Mu, Xidong; Dick, Jaimie T. A.; Fang, Miao; Gu, Dangen; Luo, Du; Zhang, Jiaen; Luo, Jianren; Hu, Yinchang

    2016-01-01

    Understanding determinants of the invasiveness and ecological impacts of alien species is amongst the most sought-after and urgent research questions in ecology. Several studies have shown the value of comparing the functional responses (FRs) of alien and native predators towards native prey, however, the technique is under-explored with herbivorous alien species and as a predictor of invasiveness as distinct from ecological impact. Here, in China, we conducted a mesocosm experiment to compare the FRs among three herbivorous snail species: the golden apple snail, Pomacea canaliculata, a highly invasive and high impact alien listed in “100 of the World's Worst Invasive Alien Species”; Planorbarius corneus, a non-invasive, low impact alien; and the Chinese native snail, Bellamya aeruginosa, when feeding on four locally occurring plant species. Further, by using a numerical response equation, we modelled the population dynamics of the snail consumers. For standard FR parameters, we found that the invasive and damaging alien snail had the highest “attack rates” a, shortest “handling times” h and also the highest estimated maximum feeding rates, 1/hT, whereas the native species had the lowest attack rates, longest handling times and lowest maximum feeding rates. The non-invasive, low impact alien species had consistently intermediate FR parameters. The invasive alien species had higher population growth potential than the native snail species, whilst that of the non-invasive alien species was intermediate. Thus, while the comparative FR approach has been proposed as a reliable method for predicting the ecological impacts of invasive predators, our results further suggest that comparative FRs could extend to predict the invasiveness and ecological impacts of alien herbivores and should be explored in other taxa and trophic groups to determine the general utility of the approach. PMID:26771658

  9. Applications of Remote Sensing to Alien Invasive Plant Studies

    Directory of Open Access Journals (Sweden)

    Gregory P. Asner

    2009-06-01

    Full Text Available Biological invasions can affect ecosystems across a wide spectrum of bioclimatic conditions. Therefore, it is often important to systematically monitor the spread of species over a broad region. Remote sensing has been an important tool for large-scale ecological studies in the past three decades, but it was not commonly used to study alien invasive plants until the mid 1990s. We synthesize previous research efforts on remote sensing of invasive plants from spatial, temporal and spectral perspectives. We also highlight a recently developed state-of-the-art image fusion technique that integrates passive and active energies concurrently collected by an imaging spectrometer and a scanning-waveform light detection and ranging (LiDAR system, respectively. This approach provides a means to detect the structure and functional properties of invasive plants of different canopy levels. Finally, we summarize regional studies of biological invasions using remote sensing, discuss the limitations of remote sensing approaches, and highlight current research needs and future directions.

  10. Impacts of invasive alien plants on water quality, with particular emphasis on South Africa

    CSIR Research Space (South Africa)

    Chamier, J

    2012-04-01

    Full Text Available . The biomass inputs of alien invasive plants, especially nitrogen fixers such as Acacia spp., alter nutrient cycles and can elevate nutrient concentrations in groundwater. Alien plant invasions alter the fire regimes in invaded areas by changing the size...

  11. Determining a charge for the clearing of invasive alien plant species ...

    African Journals Online (AJOL)

    South Africa is running out of water supply options. One option, however, is to control invasive alien plant species (IAPs) within water catchment areas and in riparian zones. The National Water Act and subsequent documentation provide a guide for the use of economic instruments to manage invasive alien plant species at ...

  12. The challenge of modelling and mapping the future distribution and impact of invasive alien species

    Science.gov (United States)

    Robert C. Venette

    2015-01-01

    Invasions from alien species can jeopardize the economic, environmental or social benefits derived from biological systems. Biosecurity measures seek to protect those systems from accidental or intentional introductions of species that might become injurious. Pest risk maps convey how the probability of invasion by an alien species or the potential consequences of that...

  13. Invasive alien plants in South Africa: how well do we understand the ecological impacts?

    CSIR Research Space (South Africa)

    Richardson, DM

    2004-01-01

    Full Text Available This paper examines the evidence for the effects of invasive alien plants in natural and semi-natural ecosystems in South Africa. Invasive alien plants are concentrated in the Western Cape, along the eastern seaboard, and into the eastern interior...

  14. Invasive alien plants used in the treatment of HIV/AIDS-related ...

    African Journals Online (AJOL)

    Results: A total of 38 invasive alien plant species belonging to 23 families were recorded to be used in the treatment of HIV/AIDS related symptoms. The largest proportion of recorded invasive alien plants belonged to the family Asteraceae with 16%. Roots were the most frequently used parts constituting 35% followed ...

  15. Worldwide Alien Invasion: A Methodological Approach to Forecast the Potential Spread of a Highly Invasive Pollinator.

    Science.gov (United States)

    Acosta, André L; Giannini, Tereza C; Imperatriz-Fonseca, Vera L; Saraiva, Antonio M

    2016-01-01

    The ecological impacts of alien species invasion are a major threat to global biodiversity. The increasing number of invasion events by alien species and the high cost and difficulty of eradicating invasive species once established require the development of new methods and tools for predicting the most susceptible areas to invasion. Invasive pollinators pose serious threats to biodiversity and human activity due to their close relationship with many plants (including crop species) and high potential competitiveness for resources with native pollinators. Although at an early stage of expansion, the bumblebee species Bombus terrestris is becoming a representative case of pollinator invasion at a global scale, particularly given its high velocity of invasive spread and the increasing number of reports of its impacts on native bees and crops in many countries. We present here a methodological framework of habitat suitability modeling that integrates new approaches for detecting habitats that are susceptible to Bombus terrestris invasion at a global scale. Our approach did not include reported invaded locations in the modeling procedure; instead, those locations were used exclusively to evaluate the accuracy of the models in predicting suitability over regions already invaded. Moreover, a new and more intuitive approach was developed to select the models and evaluate different algorithms based on their performance and predictive convergence. Finally, we present a comprehensive global map of susceptibility to Bombus terrestris invasion that highlights priority areas for monitoring.

  16. Worldwide Alien Invasion: A Methodological Approach to Forecast the Potential Spread of a Highly Invasive Pollinator.

    Directory of Open Access Journals (Sweden)

    André L Acosta

    Full Text Available The ecological impacts of alien species invasion are a major threat to global biodiversity. The increasing number of invasion events by alien species and the high cost and difficulty of eradicating invasive species once established require the development of new methods and tools for predicting the most susceptible areas to invasion. Invasive pollinators pose serious threats to biodiversity and human activity due to their close relationship with many plants (including crop species and high potential competitiveness for resources with native pollinators. Although at an early stage of expansion, the bumblebee species Bombus terrestris is becoming a representative case of pollinator invasion at a global scale, particularly given its high velocity of invasive spread and the increasing number of reports of its impacts on native bees and crops in many countries. We present here a methodological framework of habitat suitability modeling that integrates new approaches for detecting habitats that are susceptible to Bombus terrestris invasion at a global scale. Our approach did not include reported invaded locations in the modeling procedure; instead, those locations were used exclusively to evaluate the accuracy of the models in predicting suitability over regions already invaded. Moreover, a new and more intuitive approach was developed to select the models and evaluate different algorithms based on their performance and predictive convergence. Finally, we present a comprehensive global map of susceptibility to Bombus terrestris invasion that highlights priority areas for monitoring.

  17. Dna c-values of 20 invasive alien species and 3 native species in south china

    OpenAIRE

    Gong Ni; Wang Yu-Tao; Björn Lars Olof; Li Shao-Shan

    2014-01-01

    Cultivated fields and forests in South China are experiencing serious damage due to invasive alien plants. We investigated the relation between DNA C-values and invasiveness. The DNA C-values of 23 species ranged from 0.39 pg to 3.37 pg. Herbs, perennials and native species had higher mean DNA C-values than shrubs, annuals and invasive alien species. DNA C-values decreased with increasing invasiveness. Paederia scandens, a harmful native species, has the lo...

  18. Invasive alien plants benefit more from clonal integration in heterogeneous environments than natives.

    Science.gov (United States)

    Wang, Yong-Jian; Müller-Schärer, Heinz; van Kleunen, Mark; Cai, Ai-Ming; Zhang, Ping; Yan, Rong; Dong, Bi-Cheng; Yu, Fei-Hai

    2017-12-01

    What confers invasive alien plants a competitive advantage over native plants remains open to debate. Many of the world's worst invasive alien plants are clonal and able to share resources within clones (clonal integration), particularly in heterogeneous environments. Here, we tested the hypothesis that clonal integration benefits invasive clonal plants more than natives and thus confers invasives a competitive advantage. We selected five congeneric and naturally co-occurring pairs of invasive alien and native clonal plants in China, and grew pairs of connected and disconnected ramets under heterogeneous light, soil nutrient and water conditions that are commonly encountered by alien plants during their invasion into new areas. Clonal integration increased biomass of all plants in all three heterogeneous resource environments. However, invasive plants benefited more from clonal integration than natives. Consequently, invasive plants produced more biomass than natives. Our results indicate that clonal integration may confer invasive alien clonal plants a competitive advantage over natives. Therefore, differences in the ability of clonal integration could potentially explain, at least partly, the invasion success of alien clonal plants in areas where resources are heterogeneously distributed. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  19. Costs and benefits of biological control of invasive alien plants in South Africa

    CSIR Research Space (South Africa)

    Van Wilgen, BW

    2011-08-01

    Full Text Available and benefits of biological control of invasive alien plants in South Africa B.W. van Wilgen* & W.J. De Lange Centre for Invasion Biology, CSIR Natural Resources and the Environment, P.O. Box 320, Stellenbosch, 7599 South Africa This paper provides a brief..., and economic and recre- ational activities Grazing resources. Invasive alien plants have significant effects on grazing resources. Range- lands that are utilized by both domestic livestock and wildlife have become invaded by several alien plant species...

  20. Biological control of alien and invasive species in agriculture

    International Nuclear Information System (INIS)

    Calvitti, Maurizio; Moretti Riccardo; Lampazzi, Elena

    2015-01-01

    Agricultural production in Europe faces many challenges including limited availability of water, nitrogen input and fossil fuels. It is necessary, therefore, to identify methods of production and new technologies to increase the efficiency of the primary systems, guaranteeing amount of food, quality, safety and eco-sustainability . One of the most important aspects, though often undervalued in relation to the food chain, is the adversity of biological management of agricultural crops due to pests, pathogens or fitomizi with potential invasive already present in the territory or of recent origin alien. In this context, two main objectives should be implemented at the same time reduce production losses and protect the agro-ecosystem. To meet these expectations, as of January 1, 2015 all farms in the European Union countries are bound to the application of the Integrated Defense principles, as indicated by the Directive on the sustainable use of plant protection products (128/09 / EC) .In response to this and other new entomological emergencies plant health and medical-veterinary entomologist researchers of the Laboratory sustainable management of Agro-Ecosystems in ENEA, have directed their research towards the development of innovative systems for the sustainable control of invasive species of insects is in the agricultural sector that health. [it

  1. Are invasive aliens a real threat to biodiversity in South Africa?

    CSIR Research Space (South Africa)

    Van Wilgen, B

    2011-01-01

    Full Text Available South Africa has abundant biodiversity, but also many invasive alien species, especially plants and fish, that can transform ecosystems. Invading alien trees and shrubs impact on fynbos and threaten up to a quarter of the nation's plant species...

  2. Dna c-values of 20 invasive alien species and 3 native species in south china

    Directory of Open Access Journals (Sweden)

    Gong Ni

    2014-01-01

    Full Text Available Cultivated fields and forests in South China are experiencing serious damage due to invasive alien plants. We investigated the relation between DNA C-values and invasiveness. The DNA C-values of 23 species ranged from 0.39 pg to 3.37 pg. Herbs, perennials and native species had higher mean DNA C-values than shrubs, annuals and invasive alien species. DNA C-values decreased with increasing invasiveness. Paederia scandens, a harmful native species, has the lowest DNA C-value among the perennials, indicating that native species with low nuclear content may also possess an invasive potential.

  3. An inventory of invasive alien species in China

    Directory of Open Access Journals (Sweden)

    Haigen Xu

    2012-12-01

    Full Text Available Invasive alien species (IAS are a major global challenge requiring urgent action, and the Strategic Plan for Biodiversity (2011–2020 of the Convention on Biological Diversity (CBD includes a target on the issue. Meeting the target requires an understanding of invasion patterns. However, national or regional analyses of invasions are limited to developed countries. We identified 488 IAS in China’s terrestrial habitats, inland waters and marine ecosystems based on available literature and field work, including 171 animals, 265 plants, 26 fungi, 3 protists, 11 procaryots, and 12 viruses. Terrestrial plants account for 51.6% of the total number of IAS, and terrestrial invertebrates (104 species for 21.3%. Of the total numbers, 67.9% of plant IAS and 34.8% of animal IAS were introduced intentionally. All other taxa were introduced unintentionally despite very few animal and plant species that invaded naturally. In terms of habitats, 64.3% of IAS occur on farmlands, 13.9% in forests, 8.4% in marine ecosystems, 7.3% in inland waters, and 6.1% in residential areas. Half of all IAS (51.1% originate from North and South America, 18.3% from Europe, 17.3% from Asia not including China, 7.2% from Africa, 1.8% from Oceania, and the origin of the remaining 4.3% IAS is unknown. The distribution of IAS can be divided into three zones. Most IAS are distributed in coastal provinces and the Yunnan province; provinces in Middle China have fewer IAS, and most provinces in West China have the least number of IAS. Sites where IAS were first detected are mainly distributed in the coastal region, the Yunnan Province and the Xinjiang Uyghur Autonomous Region. The number of newly emerged IAS has been increasing since 1850. The cumulative number of firstly detected IAS grew exponentially.

  4. Invasive alien plants and South African rivers: a proposed approach to the prioritisation of control operations

    CSIR Research Space (South Africa)

    Van Wilgen, BW

    2007-01-01

    Full Text Available Parallel initiatives in South Africa have been addressing the prioritisation and management of invasive alien plant species, the prioritisation of rivers for the conservation of biodiversity, and broad-scale planning for water resource management...

  5. Alien invasive vascular plants in South African natural and semi-natural environments : bibliography from 1830

    CSIR Research Space (South Africa)

    Moran, VC

    1982-12-01

    Full Text Available A compilation of references to research on alien invasive plants in South Africa is given. Crop weeds and indigenous plants are not included. Reference is made to 457 publications. Keyword listings and a keyword index are provided....

  6. Proposed prioritization system for the management of invasive alien plants in South Africa

    CSIR Research Space (South Africa)

    Robertson, MP

    2003-01-01

    Full Text Available system described in this article was designed to assess objectively research and control priorities of invasive alien plants at a national scale in South Africa. The evaluation consists of seventeen criteria, grouped into five modules that assess...

  7. Invasions by alien plants in the Czech Republic: a quantitative assessment across habitats

    Czech Academy of Sciences Publication Activity Database

    Chytrý, M.; Pyšek, Petr; Tichý, L.; Knollová, I.; Danihelka, Jiří

    2005-01-01

    Roč. 77, - (2005), s. 339-354 ISSN 0032-7786 Institutional research plan: CEZ:AV0Z60050516 Keywords : habitat invasibility * alien species * Czech Republic Subject RIV: EF - Botanics Impact factor: 1.545, year: 2005

  8. Patterns of alien plant invasion across coastal bay areas in southern China

    Science.gov (United States)

    Hai Ren; Qinfeng Guo; Hong Liu; Jing Li; Qianmei Zhang; Hualin Xu; Fanghong Xu

    2014-01-01

    An understanding of the ways in which levels of invasions by alien species are correlated with environmental factors is helpful to manage the negative impacts of these invasive species. Two tropical coastal areas in South China, Shenzhen Bay and Leizhou Bay, are national nature reserves, but they are threatened by invasive plants. Here, we investigated the level of...

  9. State-space modeling indicates rapid invasion of an alien shrub in coastal dunes

    DEFF Research Database (Denmark)

    Damgaard, Christian Frølund; Nygaard, Bettina; Ejrnæs, Rasmus

    2011-01-01

    Invasion by alien plants has negative effects on coastal dunes. Monitoring local spread of invasive species depends on long-term data with sufficient spatial resolution. Bayesian state-space models are a new method for monitoring invasive plants based on unbalanced permanent-plot data. The method...

  10. Horticultural markets promote alien species invasions: an Estonian case study of herbaceous perennials

    Directory of Open Access Journals (Sweden)

    Merle Ööpik

    2013-06-01

    Full Text Available Gardening is a popular pastime, but commercial horticulture is responsible for the introduction of alien species and contributes to invasions in a variety of ways. Although an extensive international literature is available on plant invasions, it is still important at the national level to examine the influence of local factors. Accordingly, 17 nurseries in Estonia that cultivated and sold perennial alien species were selected, and a list of species and prices was compiled. The relationships between species status, and factors such as their abundance in the wild were examined statistically. A qualitative list of the nationally problematic species among herbaceous perennials was also completed. A total of 880 taxa were recorded, of which 10.3% were native and 89.7% alien. In all, 87.3% of the alien species were still confined to cultivated areas. The ecological and socio-economic characteristics of the taxa were described, and lists of the families of casual, naturalised and invasive aliens were provided. Both native and increasing wild alien species have a very similar profile on the market. Alien species that are less expensive, widely available and have more cultivars per species on the market are also more likely to escape. The invasive status and abundance of escaped aliens in an area increases with residence time. In general, socio-economic factors create new and reflect previous propagule pressures from commercial horticulture, which continuously increase the likelihood of alien species surviving and invading new areas. Our findings suggest that these national socio-economic market-related factors explain much of the invasiveness of various perennial ornamental species, and therefore regional and national authorities urgently need to regulate and control the ornamental plant trade to diminish the risk of new invasions.

  11. Distribution patterns of invasive alien species in Alabama, USA

    Directory of Open Access Journals (Sweden)

    Xiongwen Chen

    2012-12-01

    Full Text Available Invasive alien species (IAS cause environmental and economical problems. How to effectively manage all IAS at a large area is a challenge.Hypotheses about IAS (such as the “human activity” hypothesis, the “biotic acceptance” and the “biotic resistance” have been proposedfrom numerous studies. Here the state of Alabama in USA, widely occupied by IAS, is used as a case study for characterizing the emergentpatterns of IAS. The results indicate that most IAS are located in metropolitan areas and in the Black Belt area which is a historical intensiveland use area. There are positive relationships between the richness of IAS and the change of human population, the species richness and thenumber of endangered species, as well as the total road length and farmland area across Alabama. This study partially supports the abovethree hypotheses and provides a general pattern of local IAS. Based on possible processes related with IAS, some implications forstrategically managing local IAS are discussed.

  12. Effect of the internet commerce on dispersal modes of invasive alien species.

    Science.gov (United States)

    Lenda, Magdalena; Skórka, Piotr; Knops, Johannes M H; Moroń, Dawid; Sutherland, William J; Kuszewska, Karolina; Woyciechowski, Michał

    2014-01-01

    The spread of invasive alien plants has considerable environmental and economic consequences, and is one of the most challenging ecological problems. The spread of invasive alien plant species depends largely on long-distance dispersal, which is typically linked with human activity. The increasing domination of the internet will have impacts upon almost all components of our lives, including potential consequences for the spread of invasive species. To determine whether the rise of Internet commerce has any consequences for the spread of invasive alien plant species, we studied the sale of thirteen of some of the most harmful Europe invasive alien plant species sold as decorative plants from twenty-eight large, well known gardening shops in Poland that sold both via the Internet and through traditional customer sales. We also analyzed temporal changes in the number of invasive plants sold in the largest Polish internet auction portal. When sold through the Internet invasive alien plant species were transported considerably longer distances than for traditional sales. For internet sales, seeds of invasive alien plant species were transported further than were live plants saplings; this was not the case for traditional sales. Also, with e-commerce the shape of distance distribution were flattened with low skewness comparing with traditional sale where the distributions were peaked and right-skewed. Thus, e-commerce created novel modes of long-distance dispersal, while traditional sale resembled more natural dispersal modes. Moreover, analysis of sale in the biggest Polish internet auction portal showed that the number of alien specimens sold via the internet has increased markedly over recent years. Therefore internet commerce is likely to increase the rate at which ecological communities become homogenized and increase spread of invasive species by increasing the rate of long distance dispersal.

  13. Effect of the Internet Commerce on Dispersal Modes of Invasive Alien Species

    Science.gov (United States)

    Lenda, Magdalena; Skórka, Piotr; Knops, Johannes M. H.; Moroń, Dawid; Sutherland, William J.; Kuszewska, Karolina; Woyciechowski, Michał

    2014-01-01

    The spread of invasive alien plants has considerable environmental and economic consequences, and is one of the most challenging ecological problems. The spread of invasive alien plant species depends largely on long-distance dispersal, which is typically linked with human activity. The increasing domination of the internet will have impacts upon almost all components of our lives, including potential consequences for the spread of invasive species. To determine whether the rise of Internet commerce has any consequences for the spread of invasive alien plant species, we studied the sale of thirteen of some of the most harmful Europe invasive alien plant species sold as decorative plants from twenty-eight large, well known gardening shops in Poland that sold both via the Internet and through traditional customer sales. We also analyzed temporal changes in the number of invasive plants sold in the largest Polish internet auction portal. When sold through the Internet invasive alien plant species were transported considerably longer distances than for traditional sales. For internet sales, seeds of invasive alien plant species were transported further than were live plants saplings; this was not the case for traditional sales. Also, with e-commerce the shape of distance distribution were flattened with low skewness comparing with traditional sale where the distributions were peaked and right-skewed. Thus, e-commerce created novel modes of long-distance dispersal, while traditional sale resembled more natural dispersal modes. Moreover, analysis of sale in the biggest Polish internet auction portal showed that the number of alien specimens sold via the internet has increased markedly over recent years. Therefore internet commerce is likely to increase the rate at which ecological communities become homogenized and increase spread of invasive species by increasing the rate of long distance dispersal. PMID:24932498

  14. Modeling invasive alien plant species in river systems : Interaction with native ecosystem engineers and effects on hydro-morphodynamic processes

    NARCIS (Netherlands)

    van Oorschot, M.; Kleinhans, M. G.; Geerling, G.W.; Egger, G.; Leuven, R.S.E.W.; Middelkoop, H.

    2017-01-01

    Invasive alien plant species negatively impact native plant communities by out-competing species or changing abiotic and biotic conditions in their introduced range. River systems are especially vulnerable to biological invasions, because waterways can function as invasion corridors. Understanding

  15. Habitat invasions by alien plants: a quantitative comparison among Mediterranean, subcontinental and oceanic regions of Europe

    OpenAIRE

    Chytrý, Milan; Maskell, Lindsay C; Pino, Joan; Pyšek, Petr; Vilà, Montserrat; Font, Xavier; Smart, Simon M.

    2008-01-01

    1. Although invasions by alien plants are major threats to the biodiversity of natural habitats, individual habitats vary considerably in their susceptibility to invasion. Therefore the risk assessment procedures, which are used increasingly by environmental managers to inform effective planning of invasive plant control, require reliable quantitative information on the extent to which different habitats are susceptible to invasion. It is also important to know whether the leve...

  16. Ecological Risk Assessment with MCDM of Some Invasive Alien Plants in China

    Science.gov (United States)

    Xie, Guowen; Chen, Weiguang; Lin, Meizhen; Zheng, Yanling; Guo, Peiguo; Zheng, Yisheng

    Alien plant invasion is an urgent global issue that threatens the sustainable development of the ecosystem health. The study of its ecological risk assessment (ERA) could help us to prevent and reduce the invasion risk more effectively. Based on the theory of ERA and methods of the analytic hierarchy process (AHP) of multi-criteria decision-making (MCDM), and through the analyses of the characteristics and processes of alien plant invasion, this paper discusses the methodologies of ERA of alien plant invasion. The assessment procedure consisted of risk source analysis, receptor analysis, exposure and hazard assessment, integral assessment, and countermeasure of risk management. The indicator system of risk source assessment as well as the indices and formulas applied to measure the ecological loss and risk were established, and the method for comprehensively assessing the ecological risk of alien plant invasion was worked out. The result of ecological risk analysis to 9 representative invasive alien plants in China shows that the ecological risk of Erigeron annuus, Ageratum conyzoides, Alternanthera philoxeroides and Mikania midrantha is high (grade1-2), that of Oxalis corymbosa and Wedelia chinensis comes next (grade3), while Mirabilis jalapa, Pilea microphylla and Calendula officinalis of the last (grade 4). Risk strategies are put forward on this basis.

  17. Preliminary assessment of the impacts of invasive alien plants on ecosystem services in South Africa

    CSIR Research Space (South Africa)

    Van Wilgen, BW

    2006-01-01

    Full Text Available impacts on water resources. The number of invasive species considered was restricted to those with extensive current or potential distributions; 17 out of a possible 160 species in fynbos shrublands in this case. We estimate that invasive alien plants...

  18. Alien plant invasions in South Africa: driving forces and the human dimension

    CSIR Research Space (South Africa)

    Le Maitre, David C

    2004-01-01

    Full Text Available Invasive alien plants pose a substantial threat to the rich biodiversity of South Africa, and to the sustained delivery of a wide range of ecosystem services. Biological invasions are driven by human activities and mediated by culturally shaped...

  19. Impact of an Alien Invasive Shrub on Ecology of Native and Alien Invasive Mosquito Species (Diptera: Culicidae).

    Science.gov (United States)

    Muturi, Ephantus J; Gardner, Allison M; Bara, Jeffrey J

    2015-10-01

    We examined how leaf litter of alien invasive honeysuckle (Lonicera maackii Rupr.) either alone or in combination with leaf litter of one of two native tree species, sugar maple (Acer saccharum Marshall) and northern red oak (Quercus rubra L.), affects the ecology of Culex restuans Theobald, Ochlerotatus triseriatus Say, and Ochlerotatus japonicus Theobald. Experimental mesocosms containing single species litter or a mixture of honeysuckle and one of two native tree species litter were established at South Farms and Trelease Woods study sites in Urbana, IL, and examined for their effect on 1) oviposition site selection by the three mosquito species, and 2) adult production and body size of Oc. triseriatus and Oc. japonicus. There were no significant effects of study site and leaf treatment on Oc. japonicus and Oc. triseriatus oviposition preference and adult production. In contrast, significantly more Cx. restuans eggs rafts were collected at South Farms relative to Trelease Woods and in honeysuckle litter relative to native tree species litter. Significantly larger adult females of Oc. japonicus and Oc. triseriatus were collected at South Farms relative to Trelease Woods and in honeysuckle litter relative to native tree species litter. Combining honeysuckle litter with native tree species litter had additive effects on Cx. restuans oviposition preference and Oc. japonicus and Oc. triseriatus body size, with the exception of honeysuckle and northern red oak litter combination, which had antagonistic effects on Oc. triseriatus body size. We conclude that input of honeysuckle litter into container aquatic habitats may alter the life history traits of vector mosquito species. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Alien Species of Lepidium in the Flora of Romania: Invasion History and Habitat Preference

    OpenAIRE

    Culiţă SÎRBU; Adrian OPREA; Cristian Valeriu PATRICHE; Costel SAMUIL; Vasile VÎNTU

    2014-01-01

    The history of spread and habitat preferences during invasion of four alien species of Lepidium in Romania, namely L. densiflorum, L. oblongum, L. sativum, and L. virginicum are presented in this paper. The floristic records of these species, collected between 1816 and 2013, were used in the study. L. sativum was sporadically mentioned by earlier botanic references, as a casual alien plant in ruderal places. L. oblongum was reported from a single locality, but it may be considered a potential...

  1. Evaluating Hypotheses of Plant Species Invasions on Mediterranean Islands: Inverse Patterns between Alien and Endemic Species

    Directory of Open Access Journals (Sweden)

    Alexander Bjarnason

    2017-08-01

    Full Text Available Invasive alien species cause major changes to ecosystem functioning and patterns of biodiversity, and the main factors involved in invasion success remain contested. Using the Mediterranean island of Crete, Greece as a case study, we suggest a framework for analyzing spatial data of alien species distributions, based on environmental predictors, aiming to gain an understanding of their spatial patterns and spread. Mediterranean islands are under strong ecological pressure from invading species due to their restricted size and increased human impact. Four hypotheses of invasibility, the “propagule pressure hypothesis” (H1, “biotic resistance hypothesis vs. acceptance hypothesis” (H2, “disturbance-mediated hypothesis” (H3, and “environmental heterogeneity hypothesis” (H4 were tested. Using data from alien, native, and endemic vascular plant species, the propagule pressure, biotic resistance vs. acceptance, disturbance-mediated, and environmental heterogeneity hypotheses were tested with Generalized Additive Modeling (GAM of 39 models. Based on model selection, the optimal model includes the positive covariates of native species richness, the negative covariates of endemic species richness, and land area. Variance partitioning between the four hypotheses indicated that the biotic resistance vs. acceptance hypothesis explained the vast majority of the total variance. These results show that areas of high species richness have greater invasibility and support the acceptance hypothesis and “rich-get-richer” distribution of alien species. The negative correlation between alien and endemic species appears to be predominantly driven by altitude, with fewer alien and more endemic species at greater altitudes, and habitat richness. The negative relationship between alien and endemic species richness provides potential for understanding patterns of endemic and alien species on islands, contributing to more effective conservation

  2. Loss or gain? Invasive aliens and biodiversity in the Mediterranean Sea

    Energy Technology Data Exchange (ETDEWEB)

    Galil, B.S. [National Institute of Oceanography, Israel Oceanographic and Limnological Research, POB 8030, Haifa 31080 (Israel)]. E-mail: galil@post.tau.ac.il

    2007-07-01

    More than 500 alien species were listed from the Mediterranean Sea. Though no extinction of a native species is known, sudden decline in abundance, and even local extirpations, concurrent with proliferation of aliens, had been recorded. Examination of the profound ecological impacts of some of the most conspicuous invasive alien species underscores their role, among multiple anthropogenic stressors, in altering the infralittoral communities. Local population losses and niche contraction of native species may not induce immediate extirpation, but they augur reduction of genetic diversity, loss of functions, processes, and habitat structure, increase the risk of decline and extinction, and lead to biotic homogenization. The relevant environmental policy and management framework is discussed.

  3. Loss or gain? Invasive aliens and biodiversity in the Mediterranean Sea

    International Nuclear Information System (INIS)

    Galil, B.S.

    2007-01-01

    More than 500 alien species were listed from the Mediterranean Sea. Though no extinction of a native species is known, sudden decline in abundance, and even local extirpations, concurrent with proliferation of aliens, had been recorded. Examination of the profound ecological impacts of some of the most conspicuous invasive alien species underscores their role, among multiple anthropogenic stressors, in altering the infralittoral communities. Local population losses and niche contraction of native species may not induce immediate extirpation, but they augur reduction of genetic diversity, loss of functions, processes, and habitat structure, increase the risk of decline and extinction, and lead to biotic homogenization. The relevant environmental policy and management framework is discussed

  4. Do invasive alien plants benefit more from global environmental change than native plants?

    Science.gov (United States)

    Liu, Yanjie; Oduor, Ayub M O; Zhang, Zhen; Manea, Anthony; Tooth, Ifeanna M; Leishman, Michelle R; Xu, Xingliang; van Kleunen, Mark

    2017-08-01

    Invasive alien plant species threaten native biodiversity, disrupt ecosystem functions and can cause large economic damage. Plant invasions have been predicted to further increase under ongoing global environmental change. Numerous case studies have compared the performance of invasive and native plant species in response to global environmental change components (i.e. changes in mean levels of precipitation, temperature, atmospheric CO 2 concentration or nitrogen deposition). Individually, these studies usually involve low numbers of species and therefore the results cannot be generalized. Therefore, we performed a phylogenetically controlled meta-analysis to assess whether there is a general pattern of differences in invasive and native plant performance under each component of global environmental change. We compiled a database of studies that reported performance measures for 74 invasive alien plant species and 117 native plant species in response to one of the above-mentioned global environmental change components. We found that elevated temperature and CO 2 enrichment increased the performance of invasive alien plants more strongly than was the case for native plants. Invasive alien plants tended to also have a slightly stronger positive response to increased N deposition and increased precipitation than native plants, but these differences were not significant (N deposition: P = 0.051; increased precipitation: P = 0.679). Invasive alien plants tended to have a slightly stronger negative response to decreased precipitation than native plants, although this difference was also not significant (P = 0.060). So while drought could potentially reduce plant invasion, increases in the four other components of global environmental change considered, particularly global warming and atmospheric CO 2 enrichment, may further increase the spread of invasive plants in the future. © 2017 John Wiley & Sons Ltd.

  5. Would the control of invasive alien plants reduce malaria transmission? A review.

    Science.gov (United States)

    Stone, Christopher M; Witt, Arne B R; Walsh, Guillermo Cabrera; Foster, Woodbridge A; Murphy, Sean T

    2018-02-01

    Vector control has been the most effective preventive measure against malaria and other vector-borne diseases. However, due to concerns such as insecticide resistance and budget shortfalls, an integrated control approach will be required to ensure sustainable, long-term effectiveness. An integrated management strategy should entail some aspects of environmental management, relying on coordination between various scientific disciplines. Here, we review one such environmental control tactic: invasive alien plant management. This covers salient plant-mosquito interactions for both terrestrial and aquatic invasive plants and how these affect a vector's ability to transmit malaria. Invasive plants tend to have longer flowering durations, more vigorous growth, and their spread can result in an increase in biomass, particularly in areas where previously little vegetation existed. Some invasive alien plants provide shelter or resting sites for adult mosquitoes and are also attractive nectar-producing hosts, enhancing their vectorial capacity. We conclude that these plants may increase malaria transmission rates in certain environments, though many questions still need to be answered, to determine how often this conclusion holds. However, in the case of aquatic invasive plants, available evidence suggests that the management of these plants would contribute to malaria control. We also examine and review the opportunities for large-scale invasive alien plant management, including options for biological control. Finally, we highlight the research priorities that must be addressed in order to ensure that integrated vector and invasive alien plant management operate in a synergistic fashion.

  6. Origin matters: diversity affects the performance of alien invasive species but not of native species.

    Science.gov (United States)

    Sun, Yan; Müller-Schärer, Heinz; Maron, John L; Schaffner, Urs

    2015-06-01

    At local scales, it has often been found that invasibility decreases with increasing resident plant diversity. However, whether resident community diversity similarly resists invasion by alien versus native species is seldom studied. We examined this issue by invading constructed native plant assemblages that varied in species and functional richness with invasive alien or native Asteraceae species. Assemblages were also invaded with spotted knapweed, Centaurea stoebe, a native European aster that has been previously used in diversity-invasibility experiments in North America. We also conducted a field survey to explore the generality of the patterns generated from our experimental study. Both experimental and observational work revealed that increasing diversity reduced the performance of alien but not native invaders. Centaurea stoebe invading its native community performed poorly regardless of resident diversity, whereas in a parallel, previously published study conducted in North America, C. stoebe easily invaded low-diversity but not high-diversity assemblages. Our results suggest that diversity is an attribute of resident communities that makes them more or less susceptible to invasion by novel invasive alien but not native plant species.

  7. Invasive species information networks: Collaboration at multiple scales for prevention, early detection, and rapid response to invasive alien species

    Science.gov (United States)

    Simpson, Annie; Jarnevich, Catherine S.; Madsen, John; Westbrooks, Randy G.; Fournier, Christine; Mehrhoff, Les; Browne, Michael; Graham, Jim; Sellers, Elizabeth A.

    2009-01-01

    Accurate analysis of present distributions and effective modeling of future distributions of invasive alien species (IAS) are both highly dependent on the availability and accessibility of occurrence data and natural history information about the species. Invasive alien species monitoring and detection networks (such as the Invasive Plant Atlas of New England and the Invasive Plant Atlas of the MidSouth) generate occurrence data at local and regional levels within the United States, which are shared through the US National Institute of Invasive Species Science. The Inter-American Biodiversity Information Network's Invasives Information Network (I3N), facilitates cooperation on sharing invasive species occurrence data throughout the Western Hemisphere. The I3N and other national and regional networks expose their data globally via the Global Invasive Species Information Network (GISIN). International and interdisciplinary cooperation on data sharing strengthens cooperation on strategies and responses to invasions. However, limitations to effective collaboration among invasive species networks leading to successful early detection and rapid response to invasive species include: lack of interoperability; data accessibility; funding; and technical expertise. This paper proposes various solutions to these obstacles at different geographic levels and briefly describes success stories from the invasive species information networks mentioned above. Using biological informatics to facilitate global information sharing is especially critical in invasive species science, as research has shown that one of the best indicators of the invasiveness of a species is whether it has been invasive elsewhere. Data must also be shared across disciplines because natural history information (e.g. diet, predators, habitat requirements, etc.) about a species in its native range is vital for effective prevention, detection, and rapid response to an invasion. Finally, it has been our

  8. Recent cases of invasive alien mites and ticks in Japan: why is a regulatory framework needed?

    Science.gov (United States)

    Goka, Koichi; Okabe, Kimiko; Takano, Ai

    2013-02-01

    Japan's economy depends on the importation of natural resources, and as a result, Japan is subjected to a high risk of biological invasion. Although Japan has quarantine systems to protect ecosystems, agriculture, forestry, fisheries, and human health against alien species, economic globalization has resulted in an ever-increasing risk of invasion. Mite invasion is no exception. Alien species that impact natural ecosystems are regulated in Japan by the Invasive Alien Species Act. However, the law focuses only on visibly recognizable species, so that species too small to see, such as viruses, bacteria, fungi, and mites, are beyond the scope of this law. The Plant Protection Law has limited the introduction of alien pests, including mites, that are harmful to agricultural crops. Recently, the liberalization of global trade policies have increased pressure to loosen regulations on various pests, including spider mites. Infectious diseases and their causative species are quarantined under the Rabies Prevention Law, the Domestic Animal Infectious Diseases Control Law, and the Human Infectious Diseases Control Law, but these laws do not cover wildlife diseases. The most serious problem is that wild reptiles, which can be carriers of ticks and tick-borne diseases, can be freely introduced to Japan. These loopholes in Japan's regulatory system have resulted in mite and tick invasions, which affect not only wildlife communities and human society but also endemism and biological diversity of natural mite populations.

  9. The effects of an invasive alien plant (Chromolaena odorata on large African mammals

    Directory of Open Access Journals (Sweden)

    Lihle Dumalisile

    2017-11-01

    Full Text Available Alien plants have invaded most ecosystem types (terrestrial, fresh water and marine and are responsible for the loss of irreplaceable natural services on which humankind relies. They alter food quantity, quality and accessibility, and may result in declines in native species richness, which may ultimately result in extinction. For an effective management of invasive alien plants, it is important to understand the effects that such plants have on all levels of biodiversity. However, the effects that invasive alien plants, such as the Triffid weed (Chromolaena odorata, have on mammalian biodiversity, especially large mammalian species, are not well-known, although they play major ecological roles in areas such as nutrient cycling. Also, little is known about the recovery of the ecosystem following alien plant removal. This study investigated the effects of C. odorata invasion on large mammalian herbivores in Hluhluwe-iMfolozi Park and whether clearing of this plant helped in rehabilitating the habitat. We used track counts to estimate and compare species richness, diversity and abundance indices for large mammalian species between areas with differing C. odorata invasion durations (ca 2 years, ca 10 years, ca 20 years, areas with differing clearing times (cl < 2 years, cl 3–5 years and an area without any history of C. odorata invasion as a control. The results from this study show that large mammalian species utilised the uninvaded and the cleared areas more than the invaded areas. Species richness, abundance and diversity decreased with increasing invasion duration and cleared areas showed an increasing species richness and abundance. We conclude that this invasive alien plant modifies habitats and their removal does aid in the restoration of the ecosystem.

  10. Aliens in Transylvania: risk maps of invasive alien plant species in Central Romania

    Directory of Open Access Journals (Sweden)

    Heike Zimmermann

    2015-01-01

    Full Text Available Using the MAXENT algorithm, we developed risk maps for eight invasive plant species in southern Transylvania, Romania, a region undergoing drastic land-use changes. Our findings show that invasion risk increased with landscape heterogeneity. Roads and agricultural areas were most prone to invasion, whereas forests were least at risk.

  11. Annotated list of marine alien species in the Mediterranean with records of the worst invasive species

    Directory of Open Access Journals (Sweden)

    A. ZENETOS

    2005-12-01

    Full Text Available This collaborative effort by many specialists across the Mediterranean presents an updated annotated list of alien marine species in the Mediterranean Sea. Alien species have been grouped into six broad categories namely established, casual, questionable, cryptogenic, excluded and invasive, and presented in lists of major ecofunctional/taxonomic groups. The establishment success within each group is provided while the questionable and excluded records are commented in brief. A total of 963 alien species have been reported from the Mediterranean until December 2005, 218 of which have been classified as excluded (23% leaving 745 of the recorded species as valid aliens. Of these 385 (52% are already well established, 262 (35% are casual records, while 98 species (13% remain “questionable” records. The species cited in this work belong mostly to zoobenthos and in particular to Mollusca and Crustacea, while Fish and Phytobenthos are the next two groups which prevail among alien biota in the Mediterranean. The available information depends greatly on the taxonomic group examined. Thus, besides the three groups explicitly addressed in the CIESM atlas series (Fish, Decapoda/Crustacea and Mollusca, which are however updated in the present work, Polychaeta, Phytobenthos, Phytoplankton and Zooplankton are also addressed in this study. Among other zoobenthic taxa sufficiently covered in this study are Echinodermata, Sipuncula, Bryozoa and Ascidiacea. On the contrary, taxa such as Foraminifera, Amphipoda and Isopoda, that are not well studied in the Mediterranean, are insufficiently covered. A gap of knowledge is also noticed in Parasites, which, although ubiquitous and pervasive in marine systems, have been relatively unexplored as to their role in marine invasions. Conclusively the lack of funding purely systematic studies in the region has led to underestimation of the number of aliens in the Mediterranean. Emphasis is put on those species that are

  12. Minimizing Risks of Invasive Alien Plant Species in Tropical Production Forest Management

    Directory of Open Access Journals (Sweden)

    Michael Padmanaba

    2014-08-01

    Full Text Available Timber production is the most pervasive human impact on tropical forests, but studies of logging impacts have largely focused on timber species and vertebrates. This review focuses on the risk from invasive alien plant species, which has been frequently neglected in production forest management in the tropics. Our literature search resulted in 114 publications with relevant information, including books, book chapters, reports and papers. Examples of both invasions by aliens into tropical production forests and plantation forests as sources of invasions are presented. We discuss species traits and processes affecting spread and invasion, and silvicultural practices that favor invasions. We also highlight potential impacts of invasive plant species and discuss options for managing them in production forests. We suggest that future forestry practices need to reduce the risks of plant invasions by conducting surveillance for invasive species; minimizing canopy opening during harvesting; encouraging rapid canopy closure in plantations; minimizing the width of access roads; and ensuring that vehicles and other equipment are not transporting seeds of invasive species. Potential invasive species should not be planted within dispersal range of production forests. In invasive species management, forewarned is forearmed.

  13. Management and control methods of invasive alien freshwater aquatic plants: a review

    NARCIS (Netherlands)

    Hussner, Andreas; Stiers, I.; Verhofstad, M.J.J.M.; Bakker, E.S.; Grutters, B.M.C.; Haury, J.; van Valkenburg, J.L.C.H.; Brundu, G.; Newman, J.; Clayton, J.S.; Anderson, L.W.J.; Hofstra, D.

    2017-01-01

    Introduced invasive alien aquatic plants (IAAPs) threaten ecosystems due to their excessive growth and have both ecological and economic impacts. To minimize these impacts, effective management of IAAPs is required according to national or international laws and regulations (e.g. the new EU

  14. Invasive alien species under attack: natural enemies of Harmonia axyridis in the Netherlands

    NARCIS (Netherlands)

    Raak-van den Berg, C.L.; Wielink, van P.; Jong, de P.W.; Gort, G.; Haelewaters, D.; Helder, J.; Lenteren, van J.C.

    2014-01-01

    The aphid predator Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is an invasive alien species in Europe and North America with negative effects on non-target species (including a decline of native ladybird populations), as well as fruit production, and human health. It is, therefore,

  15. Does global warning increase establishment rates of invasive alien species? A centurial time series analysis

    Science.gov (United States)

    Dingcheng Huang; Robert A. Haack; Runzhi. Zhang

    2011-01-01

    The establishment rate of invasive alien insect species has been increasing worldwide during the past century. This trend has been widely attributed to increased rates of international trade and associated species introductions, but rarely linked to environmental change. To better understand and manage the bioinvasion process, it is crucial to understand the...

  16. Missing the Boat on Invasive Alien Species: A Review of Post-Secondary Curricula in Canada

    Science.gov (United States)

    Smith, Andrea L.; Bazely, Dawn R.; Yan, Norman D.

    2011-01-01

    Invasive alien species (IAS) cause major environmental and economic damage worldwide, and also threaten human food security and health. The impacts of IAS are expected to rise with continued globalization, land use modification, and climate change. Developing effective strategies to deal with IAS requires a collaborative, interdisciplinary…

  17. Pest risk maps for invasive alien species: a roadmap for improvement

    Science.gov (United States)

    Robert C. Venette; Darren J. Kriticos; Roger D. Magarey; Frank H. Koch; Richard H. A. Baker; Susan P. Worner; Nadila N. Gomez Raboteaux; Daniel W. McKenney; Erhard J. Dobesberger; Denys Yemshanov; Paul J. De Barro; William D. Hutchinson; Glenn Fowler; Tom M. Kalaris; John. Pedlar

    2010-01-01

    Pest risk maps are powerful visual communication tools to describe where invasive alien species might arrive, establish, spread, or cause harmful impacts. These maps inform strategic and tactical pest management decisions, such as potential restrictions on international trade or the design of pest surveys and domestic quarantines. Diverse methods are available to...

  18. Pest risk maps for invasive alien species: a roadmap for improvement

    Science.gov (United States)

    Robert C. Venette; Darren J. Kriticos; Roger D. Magarey; Frank H. Koch; Richard H.A. Baker; Susan P. Worner; Nadilia N. Gomez Raboteaux; Daniel W. McKenney; Erhard J. Dobesberger; Denys Yemshanov; Paul J. De Barro; William D. Hutchison; Glenn Fowler; Tom M. Kalaris; John. Pedlar

    2010-01-01

    Pest risk maps are powerful visual communication tools to describe where invasive alien species might arrive, establish, spread, or cause harmful impacts. These maps inform strategic and tactical pest management decisions, such as potential restrictions on international trade or the design of pest surveys and domestic quarantines. Diverse methods are available to...

  19. A strategic study of the impact of invasive alien plants in the high ...

    African Journals Online (AJOL)

    The aim of this study was to develop a methodology to determine the impact of upland (non-riparian) invasive alien plants in the high rainfall catchments and riparian areas in all catchments on the total surface water yield available in each of the water management areas of South Africa. This would enable the Department of ...

  20. Status of biological control projects on terrestrial invasive alien weeds in California

    Science.gov (United States)

    In cooperation with foreign scientists, we are currently developing new classical biological control agents for five species of invasive alien terrestrial weeds. Cape-Ivy. A gall-forming fly, Parafreutreta regalis, and a stem-boring moth, Digitivalva delaireae, have been favorably reviewed by TAG...

  1. Public support for invasive alien species eradication programs: insights from the Netherlands

    NARCIS (Netherlands)

    Runhaar, Hens; Vane, Maurice

    2016-01-01

    Over the last few decades, the number of invasive alien species (IAS) has increasedworldwide. IAS can have negative impacts on biodiversity, human health, and the economy. For a number of reasons, IAS policies and management schemes that have been implemented have not been sufficient to tackle the

  2. Developing thresholds of potential concern for invasive alien species: Hypotheses and concepts

    Directory of Open Access Journals (Sweden)

    Llewellyn C. Foxcroft

    2009-03-01

    Conservation implication: In accepting that species and systems are variable, and that flux is inevitable and desirable, these TPCs developed for invasive alien species specifi cally, provide end points against which monitoring can be assessed. Once a threshold is reached, the cause of the threshold being exceeded is examined and management interventions recommended.

  3. Estimates of the impacts of invasive alien plants on water flows in ...

    African Journals Online (AJOL)

    The adverse impacts of alien plant invasions on water flows have been a prime motivation for South Africa's Working for Water Programme. The approach used in this study builds on a previous national assessment in 1998 by incorporating factors that limit plant water-use, information from recent research and improved flow ...

  4. Remote sensing bio-control damage on aquatic invasive alien plant ...

    African Journals Online (AJOL)

    Naeem

    Abstract. Aquatic Invasive Alien Plant (AIAP) species are a major threat to freshwater ecosystems, placing great strain on South Africa's limited water resources. Bio-control programmes have been initiated in an effort to mitigate the negative environmental impacts associated with their presence in non-native areas. Remote ...

  5. A new approach to horizon-scanning: identifying potentially invasive alien species and their introduction pathways

    NARCIS (Netherlands)

    Matthews, Jonathan; Beringen, Ruud; Creemers, Raymond; Hollander, Hans; van Kessel, Nils; van Kleef, Hein; de Koppel, Sander van; Lemaire, Adrienne J. J.; Ode, Baudewijn; Verbrugge, Laura N. H.; Hendriks, A. Jan; Schipper, Aafke M.; van der Velde, Gerard; Leuven, Rob S. E. W.

    Invasive alien species (IAS) are considered an important threat to global biodiversity due to major ecological impacts. In 2014, the European Union (EU) introduced a regulation (EU) No 1143/2014 on the prevention and management of the introduction and spread of IAS. The first risk prioritized list

  6. Invasion of alien plants in fire-damaged forests at southern boundary of the taiga zone

    Energy Technology Data Exchange (ETDEWEB)

    Khapugin, A.A.; Vargot, E.V.; Chugunov, G.G.; Shugaev, N.I.

    2016-07-01

    Aim of the study: Biological invasions are one of the most important areas of forest research. In this study, we revealed invasibility of fire-damaged forests at the southern boundary of the taiga zone. Area of study: The Mordovia State Nature Reserve (Central Russia). Material and Methods: Altogether, 11 square plots of each 100 ×100 m were established in different types of fire-damaged forests. To test plant invasion outside the established plots, field researches were carried out by route method in fire-damaged area of the Mordovia Reserve. Main Results: Six alien species (Erigeron canadensis, E. annuus, Oenothera biennis, Lactuca serriola, Sambucus racemosa, Viola arvensis) were registered within the established plots in 2011–2014. In addition, two alien invasive plants (Solidago canadensis and Bidens frondosa) were found outside these plots. No differences were detected in invasibility of the tested forest ecosystems. Research highlights: Among the revealed alien species, Erigeron canadensis, Lactuca serriola and Solidago canadensis are the most invasive plants in forest ecosystems. The first one was observed with a high occurrence frequency and abundance in all forest types tested. The second one has not been differed by abundance, but it characterized by a high competition as well as a large biomass and a large number of seeds. Solidago canadensis penetrated to natural forest ecosystem in a short time period due to closest location of its dispersal centers near the boundary of the Mordovia Reserve. These species are the most probable invaders of the forest ecosystems. (Author)

  7. The invasive alien tree Falcataria moluccana: its impacts and management

    Science.gov (United States)

    Flint Hughes; Tracy Johnson; Amanda Uowolo

    2013-01-01

    Falcataria moluccana (Miq.) Barneby and Grimes is a large tree that has become invasive in forests and developed landscapes across many Pacific islands. A fast-growing nitrogenfixing species, it transforms invaded ecosystems by dramatically increasing nutrient inputs, suppressing native species and facilitating invasion by other weeds. Individuals rapidly reach heights...

  8. INVASIVESNET towards an International Association for Open Knowledge on Invasive Alien Species

    Science.gov (United States)

    Lucy, Frances; Roy, Helen; Simpson, Annie; Carlton, James T.; Hanson, John Mark; Magellan, Kit; Campbell, Marnie L.; Costello, Mark J.; Pagad, Shyama; Hewitt, Chad L; McDonald, Justin; Cassey, Phillip; Thomaz, Sidinei M; Katsanevakis, Stelios; Zenetos, Argyro; Tricarico, Elena; Boggero, Angela; Groom, Quentin J.; Adriaens, Tim; Vanderhoeven, Sonia; Torchin, Mark E.; Hufbauer, Ruth A.; Fuller, Pam; Carman, Mary R; Conn, David Bruce; Vitule, Jean R. S.; Canning-Clode, João; Galil, Bella S; Ojaveer, Henn; Bailey, Sarah A; Therriault, Thomas W; Claudi, Renata; Gazda, Anna; Dick, Jaimie T A; Caffrey, Joe; Witt, Arne; Kenis, Marc; Lehtiniemi, Maiju; Helmisaari, Harry; Panov, Vadim E

    2016-01-01

    In a world where invasive alien species (IAS) are recognised as one of the major threats to biodiversity, leading scientists from five continents have come together to propose the concept of developing an international association for open knowledge and open data on IAS—termed “INVASIVESNET”. This new association will facilitate greater understanding and improved management of invasive alien species (IAS) and biological invasions globally, by developing a sustainable network of networks for effective knowledge exchange. In addition to their inclusion in the CBD Strategic Plan for Biodiversity, the increasing ecological, social, cultural and economic impacts associated with IAS have driven the development of multiple legal instruments and policies. This increases the need for greater co-ordination, co-operation, and information exchange among scientists, management, the community of practice and the public.

  9. Seven Recommendations to Make Your Invasive Alien Species Data More Useful

    Directory of Open Access Journals (Sweden)

    Quentin J. Groom

    2017-06-01

    Full Text Available Science-based strategies to tackle biological invasions depend on recent, accurate, well-documented, standardized and openly accessible information on alien species. Currently and historically, biodiversity data are scattered in numerous disconnected data silos that lack interoperability. The situation is no different for alien species data, and this obstructs efficient retrieval, combination, and use of these kinds of information for research and policy-making. Standardization and interoperability are particularly important as many alien species related research and policy activities require pooling data. We describe seven ways that data on alien species can be made more accessible and useful, based on the results of a European Cooperation in Science and Technology (COST workshop: (1 Create data management plans; (2 Increase interoperability of information sources; (3 Document data through metadata; (4 Format data using existing standards; (5 Adopt controlled vocabularies; (6 Increase data availability; and (7 Ensure long-term data preservation. We identify four properties specific and integral to alien species data (species status, introduction pathway, degree of establishment, and impact mechanism that are either missing from existing data standards or lack a recommended controlled vocabulary. Improved access to accurate, real-time and historical data will repay the long-term investment in data management infrastructure, by providing more accurate, timely and realistic assessments and analyses. If we improve core biodiversity data standards by developing their relevance to alien species, it will allow the automation of common activities regarding data processing in support of environmental policy. Furthermore, we call for considerable effort to maintain, update, standardize, archive, and aggregate datasets, to ensure proper valorization of alien species data and information before they become obsolete or lost.

  10. Seven recommendations to make your invasive alien species data more useful

    Science.gov (United States)

    Groom, Quentin J.; Adriaens, Tim; Desmet, Peter; Simpson, Annie; De Wever, Aaike; Bazos, Ioannis; Cardoso, Ana Cristina; Charles, Lucinda; Christopoulou, Anastasia; Gazda, Anna; Helmisaari, Harry; Hobern, Donald; Josefsson, Melanie; Lucy, Frances; Marisavljevic, Dragana; Oszako, Tomasz; Pergl, Jan; Petrovic-Obradovic, Olivera; Prévot, Céline; Ravn, Hans Peter; Richards, Gareth; Roques, Alain; Roy, Helen; Rozenberg, Marie-Anne A.; Scalera, Riccardo; Tricarico, Elena; Trichkova, Teodora; Vercayie, Diemer; Zenetos, Argyro; Vanderhoeven, Sonia

    2017-01-01

    Science-based strategies to tackle biological invasions depend on recent, accurate, well-documented, standardized and openly accessible information on alien species. Currently and historically, biodiversity data are scattered in numerous disconnected data silos that lack interoperability. The situation is no different for alien species data, and this obstructs efficient retrieval, combination, and use of these kinds of information for research and policy-making. Standardization and interoperability are particularly important as many alien species related research and policy activities require pooling data. We describe seven ways that data on alien species can be made more accessible and useful, based on the results of a European Cooperation in Science and Technology (COST) workshop: (1) Create data management plans; (2) Increase interoperability of information sources; (3) Document data through metadata; (4) Format data using existing standards; (5) Adopt controlled vocabularies; (6) Increase data availability; and (7) Ensure long-term data preservation. We identify four properties specific and integral to alien species data (species status, introduction pathway, degree of establishment, and impact mechanism) that are either missing from existing data standards or lack a recommended controlled vocabulary. Improved access to accurate, real-time and historical data will repay the long-term investment in data management infrastructure, by providing more accurate, timely and realistic assessments and analyses. If we improve core biodiversity data standards by developing their relevance to alien species, it will allow the automation of common activities regarding data processing in support of environmental policy. Furthermore, we call for considerable effort to maintain, update, standardize, archive, and aggregate datasets, to ensure proper valorization of alien species data and information before they become obsolete or lost.

  11. Clearing a Path Towards Effective Alien Invasive Control: the Legal Conundrum

    Directory of Open Access Journals (Sweden)

    AR Patterson

    2006-05-01

    Full Text Available Alien invasive plants pose significant ecological, social and economic challenges for South Africa. These species threaten South Africa’s rich biodiversity, deplete our scarce water resources, reduce the agricultural potential of land, cause soil erosion and intensify flooding and fires. According to recent estimations, over eight percent of land in South Africa has been invaded by these species and at current rates of expansion their impact could double in the next fifteen years. In an attempt to curb the impending crises, the South African government has promulgated eleven national and various provincial laws which contain mechanisms for regulating the different threats posed by alien invasive plants. Certain of these laws are framework in nature while the majority are sectoral and aimed at regulating these species for one of the following four main purposes: biodiversity conservation; water conservation; agricultural management; and fire risk management. The responsibility for administering these laws spans four national departments, nine provincial environmental authorities, provincial conservation authorities, numerous local and statutory authorities. This fragmented regime, coupled with the adoption of a command and control approach to regulation, has proven inept in effectively regulating the spread of alien invasive plants in South Africa. This reality led the previous Minister of Environmental Affairs and Tourism, Mr Valli Moosa, to call for the development of a “coherent legislative framework … streamlined along the lines of the principles endorsed by the Convention on Biological Diversity”. This article critically analyses the government’s attempts to develop such a “coherent legislative framework” to regulate alien invasive plants in light of recent legislative reform. It is divided into two parts. Part one critically considers South Africa’s current laws of relevance to alien invasive plants with specific emphasis on

  12. Invasive Alien Species of Terrestrial Vegetation of North-Eastern Uttar Pradesh

    Directory of Open Access Journals (Sweden)

    Sumit Srivastava

    2014-01-01

    Full Text Available The vegetational landscape of north-eastern Terai region at the foot hills of Central Himalayas is a mosaic of grassland, old-field, wasteland, and forest ecosystems. Like many other parts of the country, this region is also infested with alien intruders which not only interfere with the growth and production of food crops but also exercise adverse effects on the biodiversity of native species. The present study attempts to catalogue the invasive alien species of the terrestrial vegetation of north-eastern Uttar Pradesh especially with reference to their habit, taxonomic position, and nativity. A total of 1135 plant species within 580 genera under 119 families are so far known to occur in the region. Of these, only 149 species within 100 genera under 41 families have been found to be invasive aliens as evident from their center of origin, past history, nature of aggregation, and invasion observed under field conditions. About 80% of these invaders have been introduced from neotropics. Out of 173 invasive plants across India, this region shares 149 species, out of which 66% of species have come from Tropical America, 14% from African continent, and the rest from other countries. A better planning in the form of early identification and reporting of infestation and spread of noxious weeds is needed for their control.

  13. Are Photosynthetic Characteristics and Energetic Cost Important Invasive Traits for Alien Sonneratia Species in South China?

    Science.gov (United States)

    Li, Feng-Lan; Zan, Qi-Jie; Hu, Zheng-Yu; Shin, Paul-K S; Cheung, Siu-Gin; Wong, Yuk-Shan; Tam, Nora Fung-Yee; Lei, An-Ping

    2016-01-01

    A higher photosynthesis and lower energetic cost are recognized as important characteristics for invasive species, but whether these traits are also important for the ability of alien mangrove species to become invasive has seldom been reported. A microcosm study was conducted to compare the photosynthetic characteristics, energetic cost indices and other growth traits between two alien species (Sonneratia apetala and S. caseolaris) and four native mangrove species over four seasons in a subtropical mangrove nature reserve in Shenzhen, South China. The aim of the study was to evaluate the invasive potential of Sonneratia based on these physiological responses. The annual average net photosynthetic rate (Pn), stomatal conductance (Gs) and total carbon assimilation per unit leaf area (Atotal) of the two alien Sonneratia species were significantly higher than the values of the native mangroves. In contrast, the opposite results were obtained for the leaf construction cost (CC) per unit dry mass (CCM) and CC per unit area (CCA) values. The higher Atotal and lower CC values resulted in a 72% higher photosynthetic energy-use efficiency (PEUE) for Sonneratia compared to native mangroves, leading to a higher relative growth rate (RGR) of the biomass and height of Sonneratia with the respective values being 51% and 119% higher than those of the native species. Higher photosynthetic indices for Sonneratia compared to native species were found in all seasons except winter, whereas lower CC values were found in all four seasons. The present findings reveal that alien Sonneratia species may adapt well and become invasive in subtropical mangrove wetlands in Shenzhen due to their higher photosynthetic characteristics coupled with lower costs in energy use, leading to a higher PEUE. The comparison of these physiological responses between S. apetala and S. caseolaris reveal that the former species is more invasive than the latter one, thus requiring more attention in future.

  14. Are soil mite assemblages structured by the identity of native and invasive alien grasses?

    Science.gov (United States)

    St John, Mark G; Wall, Diana H; Hunt, H William

    2006-05-01

    Associations between plants and animals in aboveground communities are often predictable and specific. This has been exploited for the purposes of estimating the diversity of animal species based on the diversity of plant species. The introduction of invasive alien plants into an ecosystem can result in dramatic changes in both the native plant and animal assemblages. Few data exist at the species level to determine whether belowground animal assemblages share the same degree of association to plants. The hypotheses that soil mites (Acari) form assemblages specifically associated with different native grass species in an unmanipulated natural ecosystem and that invasive alien grasses will impact soil mite assemblage composition in this setting were tested. Soil mites sampled beneath five native and two invasive alien species of grasses at the Konza Prairie Biological Station, Kansas, USA, were similarly abundant, species rich, diverse, and taxonomically distinct. No mite species had affinities for a specific grass species. There was no evidence from analysis of similarity, canonical correspondence analysis, or a nonparametric assemblage analysis that the assemblage composition of soil mites was specific to grass species. Results suggest that soil mite assemblages were more related to characteristics of the plant assemblage as a whole or prevailing soil conditions. The most recent invasive alien grass did not support a successionally younger mite fauna, based on the ratio of mesostigmatid to oribatid mites, and neither of the two invasive grasses influenced mite assemblage structure, possibly because they had not yet substantially altered the soil environment. Our results suggest that extrapolations of soil mite diversity based on assumptions of plant specificity would be invalid.

  15. Fire-driven alien invasion in a fire-adapted ecosystem

    Science.gov (United States)

    Keeley, Jon E.; Brennan, Teresa J.

    2012-01-01

    Disturbance plays a key role in many alien plant invasions. However, often the main driver of invasion is not disturbance per se but alterations in the disturbance regime. In some fire-adapted shrublands, the community is highly resilient to infrequent, high-intensity fires, but changes in the fire regime that result in shorter fire intervals may make these communities more susceptible to alien plant invasions. This study examines several wildfire events that resulted in short fire intervals in California chaparral shrublands. In one study, we compared postfire recovery patterns in sites with different prefire stand ages (3 and 24 years), and in another study we compared sites that had burned once in four years with sites that had burned twice in this period. The population size of the dominant native shrub Adenostoma fasciculatum was drastically reduced following fire in the 3-year sites relative to the 24-year sites. The 3-year sites had much greater alien plant cover and significantly lower plant diversity than the 24-year sites. In a separate study, repeat fires four years apart on the same sites showed that annual species increased significantly after the second fire, and alien annuals far outnumbered native annuals. Aliens included both annual grasses and annual forbs and were negatively correlated with woody plant cover. Native woody species regenerated well after the first fire but declined after the second fire, and one obligate seeding shrub was extirpated from two sites by the repeat fires. It is concluded that some fire-adapted shrublands are vulnerable to changes in fire regime, and this can lead to a loss of native diversity and put the community on a trajectory towards type conversion from a woody to an herbaceous system. Such changes result in alterations in the proportion of natives to non-natives, changes in functional types from deeply rooted shrubs to shallow rooted grasses and forbs, increased fire frequency due to the increase in fine fuels

  16. The origin of invasion of an alien frog species in Tibet, China.

    Science.gov (United States)

    Wang, Supen; Fan, Liqing; Liu, Conghui; Li, Jiaqi; Gao, Xu; Zhu, Wei; Li, Yiming

    2017-12-01

    Identifying the origins of alien species has important implications for effectively controlling the spread of alien species. The black-spotted frog Pelophylax nigromaculatus , originally from East Asia, has become an alien species on the Tibetan Plateau (TP). In this study, we collected 300 individuals of P. nigromaculatus from 13 native regions and 2 invasive regions (including Nyingchi and Lhasa) on the TP. To identify the source region of the TP introductions, we sequenced portions of the mitochondrial cyt b gene. We sequenced a ∼600-bp portion of the mitochondrial cyt b gene to identify 69 haplotypes (124 polymorphic sites) in all sampled populations. According to the network results, we suggest that the P. nigromaculatus found on the TP was most likely originated from Chongqing by human introduction. Furthermore, we found that the genetic diversity was significantly lower for invasive than for native sites due to founder effects. Our study provides genetic evidence that this alien species invaded the cold environment of high elevations and expanded the distribution of P. nigromaculatus in China.

  17. Riparian vegetation: degradation, alien plant invasions, and restoration prospects

    Czech Academy of Sciences Publication Activity Database

    Richardson, D. M.; Holmes, P. M.; Esler, K. J.; Galatowitsch, S. M.; Stromberg, J. C.; Kirkman, S. P.; Pyšek, Petr; Hobbs, R. J.

    2007-01-01

    Roč. 13, č. 1 (2007), s. 126-139 ISSN 1366-9516 Institutional research plan: CEZ:AV0Z60050516 Keywords : riparian habitats * plant invasions * biogeography Subject RIV: EF - Botanics Impact factor: 2.965, year: 2007

  18. Distribution of the invasive alien weed, Lantana camara , and its ...

    African Journals Online (AJOL)

    Lantana camara (lantana) is a major invasive shrub globally, impacting upon biodiversity, economies, ecosystem services, and driving socio-ecological change. The aim of this study was to determine the current and potential distribution of lantana in eastern Africa and its livelihood impacts in one region in Uganda.

  19. Alien interference: disruption of infochemical networks by invasive insect herbivores

    Czech Academy of Sciences Publication Activity Database

    Desurmont, G.A.; Harvey, J.; Van Dam, N. M.; Cristescu, S. M.; Schiestl, F.P.; Cozzolino, S.; Anderson, P.; Larsson, M. C.; Kindlmann, Pavel; Danner, H.; Turlings, C. J.

    2014-01-01

    Roč. 37, č. 8 (2014), s. 1854-1865 ISSN 0140-7791 Institutional support: RVO:67179843 Keywords : invasive species * multitrophic interactions * plant–insect interactions * plant volatiles Subject RIV: EH - Ecology, Behaviour Impact factor: 6.960, year: 2014

  20. A globally-distributed alien invasive species poses risks to United States imperiled species.

    Science.gov (United States)

    McClure, Meredith L; Burdett, Christopher L; Farnsworth, Matthew L; Sweeney, Steven J; Miller, Ryan S

    2018-03-28

    In the midst of Earth's sixth mass extinction event, non-native species are a driving factor in many imperiled species' declines. One of the most widespread and destructive alien invasive species in the world, wild pigs (Sus scrofa) threaten native species through predation, habitat destruction, competition, and disease transmission. We show that wild pigs co-occur with up to 87.2% of imperiled species in the contiguous U.S. identified as susceptible to their direct impacts, and we project increases in both the number of species at risk and the geographic extent of risks by 2025. Wild pigs may therefore present a severe threat to U.S. imperiled species, with serious implications for management of at-risk species throughout wild pigs' global distribution. We offer guidance for efficient allocation of research effort and conservation resources across species and regions using a simple approach that can be applied to wild pigs and other alien invasive species globally.

  1. The new record for Turkish invasive alien insect fauna Anoplophora chinensis (Forster, 1771 (Coleoptera: Cerambycidae

    Directory of Open Access Journals (Sweden)

    Erdem Hızal

    2015-01-01

    Full Text Available International trade is increasing rapidly with developing transportation routes. As a result of this, it became easier for many animal species to move from their natural habitats with the break down of the natural barriers between countries and continents. Insects take an important place among these animals. Insect populations are controlled by several factors in their natural habitats, but they causes important problems as they move by living plants and wood materials to another area. They are so called invasive alien insect species in their new location. These species’ common characteristics are fast growth and reproduction, high dispersal ability, tolerance of wide range of enviromental conditions and ability to feed with various food types. The increase in importing of the plants and wood material in the recent years has been causing the prensence of these species in Turkey. In this research Anoplophora chinensis (Forster, 1771 (Coleoptera; Cerambycidae is given as a new record to Turkish invasive alien insect species fauna.

  2. Invasion success of alien plants: do habitat affinities in the native distribution range matter?

    Czech Academy of Sciences Publication Activity Database

    Hejda, Martin; Pyšek, Petr; Pergl, Jan; Sádlo, Jiří; Chytrý, M.; Jarošík, Vojtěch

    2009-01-01

    Roč. 18, č. 3 (2009), s. 372-382 ISSN 1466-822X R&D Projects: GA MŠk LC06073 Grant - others:Evropská komise(XE) GOCE-CT-2003-506675 Institutional research plan: CEZ:AV0Z60050516 Keywords : biological invasions * casual aliens * Central Europe Subject RIV: EF - Botanics Impact factor: 5.913, year: 2009

  3. INVASIVE ALIEN PLANT SPECIES USED FOR THE TREATMENT OF VARIOUS DISEASES IN LIMPOPO PROVINCE, SOUTH AFRICA

    OpenAIRE

    Maema, Lesibana Peter; Potgieter, Martin; Mahlo, Salome Mamokone

    2016-01-01

    Background: Invasive alien plant species (IAPs) are plants that have migrated from one geographical region to non-native region either intentional or unintentional. The general view of IAPs in environment is regarded as destructive to the ecosystem and they pose threat to native vegetation and species. However, some of these IAPS are utilized by local inhabitants as a substitute for scarce indigenous plants. The aim of the study is to conduct ethnobotanical survey on medicinal usage of invasi...

  4. Sentinel trees as a tool to forecast invasions of alien plant pathogens.

    Directory of Open Access Journals (Sweden)

    AnnaMaria Vettraino

    Full Text Available Recent disease outbreaks caused by alien invasive pathogens into European forests posed a serious threat to forest sustainability with relevant environmental and economic effects. Many of the alien tree pathogens recently introduced into Europe were not previously included on any quarantine lists, thus they were not subject to phytosanitary inspections. The identification and description of alien fungi potentially pathogenic to native European flora before their introduction in Europe, is a paramount need in order to limit the risk of invasion and the impact to forest ecosystems. To determine the potential invasive fungi, a sentinel trees plot was established in Fuyang, China, using healthy seedlings of European tree species including Quercus petreae, Q. suber, and Q. ilex. The fungal assemblage associated with symptomatic specimens was studied using the tag-encoded 454 pyrosequencing of the nuclear ribosomal internal transcribed spacer-1 (ITS 1. Taxa with probable Asiatic origin were identified and included plant pathogenic genera. These results indicate that sentinel plants may be a strategic tool to improve the prevention of bioinvasions.

  5. Alien conifer invasions in South America: short fuse burning?

    CSIR Research Space (South Africa)

    Richardson, DM

    2007-01-01

    Full Text Available , in the management of conifer invasions in the southern hemisphere provides the opportunity to transfer learning and experience to South America. With this in mind, 15 researchers from Argentina, Brazil, Chile, New Zealand, South Africa and the USA assembled... up to 80% of the total cost of the plantings, with no require- ments to control the natural regeneration that follows (SAGPyA 1999). Similar incentives are offered in Chile. The workshop provided an important opportunity to develop a consensus...

  6. Mycorrhizal status helps explain invasion success of alien plant species

    Czech Academy of Sciences Publication Activity Database

    Menzel, A.; Hempel, S.; Klotz, S.; Moora, M.; Pyšek, Petr; Rillig, M. C.; Zobel, M.; Kühn, I.

    2017-01-01

    Roč. 98, č. 1 (2017), s. 92-102 ISSN 0012-9658 R&D Projects: GA ČR GB14-36079G Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : plant invasion * mycorrhiza * naturalization Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 4.809, year: 2016

  7. Unusual population attributes of invasive red-eared slider turtles (Trachemys scripta elegans) in Japan: do they have a performance advantage?

    Science.gov (United States)

    Taniguchi, Mari; Lovich, Jeffrey E.; Mine, Kanako; Ueno, Shintaro; Kamezaki, Naoki

    2017-01-01

    The slider turtle (Trachemys scripta Thunberg in Schoepff, 1792) is native to the USA and Mexico. Due to the popularity of their colorful hatchlings as pets, they have been exported worldwide and are now present on all continents, except Antarctica. Slider turtles are well-established in Japan and occupy aquatic habitats in urban and agricultural areas, to the detriment of native turtles with which they compete. We asked the overall question, do slider turtles in Japan have a performance advantage because they are liberated from the numerous competing turtle species in their native range and released from many of their natural predators? Traits compared included various measures of adult body size (mean, maximum), female size at maturity as measured by size of gravid females, clutch size, population density and biomass, sex ratio, and sexual size dimorphism, the latter two a partial reflection of growth and maturity differences between the sexes. We sampled slider turtle populations in three habitats in Japan and compared population attributes with published data for the species from throughout its native range in the USA. Mean male body sizes were at the lower end of values from the USA suggesting that males in Japan may mature at smaller body sizes. The smallest gravid females in Japan mature at smaller body sizes but have mean clutch sizes larger than some populations in the USA. Compared to most populations in the USA, slider turtles achieve higher densities and biomasses in Japanese wetlands, especially the lotic system we sampled. Sex ratios were female-biased, the opposite of what is reported for many populations in protected areas of the USA. Sexual size dimorphism was enhanced relative to native populations with females as the larger sex. The enhanced dimorphism is likely a result of earlier size of maturity in Japanese males and the large size of mature (gravid) Japanese females. Slider turtles appear to have a performance advantage over native turtles in

  8. Invasive alien predator causes rapid declines of native European ladybirds

    Czech Academy of Sciences Publication Activity Database

    Roy, H. E.; Adriaens, T.; Isaac, N. J. B.; Kenis, M.; Onkelinx, T.; San Martin, G.; Brown, P. M. J.; Hautier, L.; Poland, R.; Roy, D. B.; Comont, R.; Eschen, R.; Frost, R.; Zindel, R.; Van Vlaenderen, J.; Nedvěd, Oldřich; Ravn, H. P.; Grégoire, J.-C.; de Biseau, J.-C.; Maes, D.

    2012-01-01

    Roč. 18, č. 7 (2012), s. 717-725 ISSN 1366-9516 Grant - others:MZe ČR(CZ) QH82047; Swiss Federal Office for the Environment(SE) F232-0377; project ALARM(BE) GOCE-CT-2003-506675 Institutional support: RVO:60077344 Keywords : biological control * biological invasions * citizen science Subject RIV: EH - Ecology, Behaviour Impact factor: 6.122, year: 2012 http://onlinelibrary.wiley.com/doi/10.1111/j.1472-4642.2012.00883.x/pdf

  9. Invasive alien plant species dynamics in the Himalayan region under climate change.

    Science.gov (United States)

    Lamsal, Pramod; Kumar, Lalit; Aryal, Achyut; Atreya, Kishor

    2018-01-25

    Climate change will impact the dynamics of invasive alien plant species (IAPS). However, the ability of IAPS under changing climate to invade mountain ecosystems, particularly the Himalayan region, is less known. This study investigates the current and future habitat of five IAPS of the Himalayan region using MaxEnt and two representative concentration pathways (RCPs). Two invasive species, Ageratum conyzoides and Parthenium hysterophorus, will lose overall suitable area by 2070, while Ageratina adenophora, Chromolaena odorata and Lantana camara will gain suitable areas and all of them will retain most of the current habitat as stable. The southern Himalayan foothills will mostly conserve species ecological niches, while suitability of all the five species will decrease with increasing elevation. Such invasion dynamics in the Himalayan region could have impacts on numerous ecosystems and their biota, ecosystem services and human well-being. Trans-boundary response strategies suitable to the local context of the region could buffer some of the likely invasion impacts.

  10. Changes in the invasion level, and impact of alien plants in Finnish semi-natural agricultural habitats

    Directory of Open Access Journals (Sweden)

    Miia Jauni

    2012-06-01

    Full Text Available Using dataset of 508 transects of 50 m2, we assessed changes in the invasion level of alien plant species in semi-natural agricultural habitats in three study years (2001, 2005 and 2010 in four geographical regions of Finland. In addition, the impact of environmental factors on the occurrence of the most common neophytes (alien species introduced after the 17th century and the impact of neophytes on native species diversity were studied. In total, 37 neophyte species were detected, but neophytes regarded as highly invasive were rare and occasional. We detected spatio-temporal variation in the invasion level, but it changed according to the measure used. For instance, alien species diversity was lower in south-western Finland than in other years in 2005, and the relative alien species richness was highest in southern and lowest in eastern Finland. Preferences for environmental conditions (disturbance, habitat type and geographical location and the impact on plant diversity varied among the most common neophytes. The most common neophytes were positively rather than negatively associated with native and alien species diversity. The results suggest that alien species management and control methods should be species-specific and considered case-by-case. Neophytes do not yet cause severe problems, but regular monitoring is needed to detect changes in their invasion levels.

  11. Potential establishment of alien-invasive forest insect species in the United States: where and how many?

    Science.gov (United States)

    Frank H. Koch; Denys Yemshanov; Manuel Colunga-Garcia; Roger D. Magarey; William D. Smith

    2011-01-01

    International trade is widely acknowledged as a conduit for movement of invasive species, but few studies have directly quantified the invasion risk confronting individual locations of interest. This study presents estimates of the likelihood of successful entry for alien forest insect species at more than 3,000 urban areas in the contiguous United States (US). To...

  12. Environmental risk assessment for invasive alien species : A case study of apple snails affecting ecosystem services in Europe

    NARCIS (Netherlands)

    Gilioli, Gianni; Schrader, Gritta; Carlsson, Nils; van Donk, Ellen; van Leeuwen, Casper H.A.; Martín, Pablo R.; Pasquali, Sara; Vilà, Montserrat; Vos, Sybren

    2017-01-01

    The assessment of the risk posed by invasive alien species (IAS) to the environment is a component of increasing importance for Pest Risk Analysis. Standardized and comprehensive procedures to assess their impacts on ecosystem services have been developed only recently. The invasive apple snails

  13. Environmental risk assessment for invasive alien species: A case study of apple snails affecting ecosystem services in Europe

    NARCIS (Netherlands)

    Gilioli, Gianni; Schrader, Gritta; Carlsson, Nils; van Donk, Ellen; van Leeuwen, Casper H.A.; Martín, Pablo R.; Pasquali, Sara; Vilà, Montserrat; Vos, Sybren

    Abstract The assessment of the risk posed by invasive alien species (IAS) to the environment is a component of increasing importance for Pest Risk Analysis. Standardized and comprehensive procedures to assess their impacts on ecosystem services have been developed only recently. The invasive apple

  14. Leaf litter traits of invasive alien species slow down decomposition compared to Spanish natives: a broad phylogenetic comparison.

    NARCIS (Netherlands)

    Godoy, O.; Castro Diez, P.; van Logtestijn, R.S.P; Cornelissen, J.H.C.; Valladares, F.

    2010-01-01

    Leaf traits related to the performance of invasive alien species can influence nutrient cycling through litter decomposition. However, there is no consensus yet about whether there are consistent differences in functional leaf traits between invasive and native species that also manifest themselves

  15. Invasive alien plants in protected areas within city borders, LODZ (poland)

    International Nuclear Information System (INIS)

    Anna, B.; Grzegorz, W.J.; Krason, K.

    2017-01-01

    The aim of the study was to present the occurrence of invasive alien plant species in two forest reserves: L as Lagiewnicki a nd P olesie Konstantynowskie , located within the city of Lodz (Central Poland). Currently, five vascular plants (Impatiens parviflora, Juncus tenuis, Padus serotina, Quercus rubra, Robinia pseudoacacia) and one moss (Orthodontium lineare) considered as invasive were found in the studied reserves. Invasive plant species accounted for a small percentage of the flora in the studied reserves, and their sites were mainly concentrated in areas transformed by human activity. The most common species were Impatiens parviflora and Padus serotina. Due to the location of the reserves within city borders and the proven negative effect of the found species on ecological systems, their sites should be monitored. (author)

  16. ALEX index enables detection of alien macroalgae invasions across habitats within a marine protected area.

    Science.gov (United States)

    Piazzi, L; Gennaro, P; Atzori, F; Cadoni, N; Cinti, M F; Frau, F; Ceccherelli, G

    2018-03-01

    A modified version of the ALien Biotic IndEX (ALEX) has been recently proposed to evaluate biological invasions in macroalgal assemblages. ALEX was applied in a Marine Protected Area where a recreational-fishing port is present testing the following hypotheses: ALEX increases with the distance from the port, it changes between the two directions off the port and it changes among three different habitats: Cystoseira beds, algal turf and dead matte of the seagrass Posidonia oceanica. A total of 78 native macroalgal taxa and 4 introduced species were found, the Chlorophyta Caulerpa cylindracea and the Rhodophyta Apoglossum gregarium, Acrothamnion preissii and Womersleyella setacea. All study sites were in high quality status highlighting that the assemblages investigated were at an early stage of NIS invasion. However, ALEX detected different values among conditions and habitats within the MPA, suggesting a local dynamics of NIS spread and different resistance to invasion of the investigated habitats. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Stakeholder Perceptions of an Ecosystem Services Approach to Clearing Invasive Alien Plants on Private Land

    Directory of Open Access Journals (Sweden)

    Lauren S. Urgenson

    2013-03-01

    Full Text Available Incentivizing private landowners and other stakeholders is central to the effective conservation of ecosystem services in working landscapes. To better understand how to design effective incentives, the perceptions of landowners and other stakeholders are explored regarding a proposed approach to clearing invasive alien plants on private land in the Western Cape Province, South Africa. The public funded national program, Working for Water, conserves ecosystem services while employing and training people from marginalized sectors of society to clear these plants. Private landowner involvement is a key conservation challenge, because without adequate landowner involvement, invasive alien plants persist on the landscape and continuously reinvade cleared areas. We collected interview data from private landowners in three study sites, and web-survey data from conservation professionals and Working for Water managers, in order to compare stakeholder perceptions of (1 government and landowners' responsibilities for clearing invasive alien plants; (2 existing and proposed policy tools; and (3 the extent to which stakeholders consider the proposed financial incentive to be sufficient. There was significant consensus among stakeholders concerning their preference for shared landowner and government responsibility and for a policy mix that combines incentives with disincentives. Landowners from the three study sites differed in the level of responsibility they were willing to assume. Stakeholders also diverged in terms of their perceptions of the proposed financial incentives. Furthermore, the perspectives of landowners were strongly associated with ecological and social features of the landscapes in which they are located. Understanding stakeholders' points of view within their differing contexts is shown to be a valuable means of gaining insight into the opportunities and constraints that face ecosystem service conservation in working landscapes.

  18. Alien plant invasions and native plant extinctions: a six-threshold framework

    Science.gov (United States)

    Downey, Paul O.; Richardson, David M.

    2016-01-01

    Biological invasions are widely acknowledged as a major threat to global biodiversity. Species from all major taxonomic groups have become invasive. The range of impacts of invasive taxa and the overall magnitude of the threat is increasing. Plants comprise the biggest and best-studied group of invasive species. There is a growing debate; however, regarding the nature of the alien plant threat—in particular whether the outcome is likely to be the widespread extinction of native plant species. The debate has raised questions on whether the threat posed by invasive plants to native plants has been overstated. We provide a conceptual framework to guide discussion on this topic, in which the threat posed by invasive plants is considered in the context of a progression from no impact through to extinction. We define six thresholds along the ‘extinction trajectory’, global extinction being the final threshold. Although there are no documented examples of either ‘in the wild’ (Threshold 5) or global extinctions (Threshold 6) of native plants that are attributable solely to plant invasions, there is evidence that native plants have crossed or breached other thresholds along the extinction trajectory due to the impacts associated with plant invasions. Several factors may be masking where native species are on the trajectory; these include a lack of appropriate data to accurately map the position of species on the trajectory, the timeframe required to definitively state that extinctions have occurred and management interventions. Such interventions, focussing mainly on Thresholds 1–3 (a declining population through to the local extinction of a population), are likely to alter the extinction trajectory of some species. The critical issue for conservation managers is the trend, because interventions must be implemented before extinctions occur. Thus the lack of evidence for extinctions attributable to plant invasions does not mean we should disregard the broader

  19. Alien invasions and the game of hide and seek in Patagonia.

    Directory of Open Access Journals (Sweden)

    Martin Lindegren

    Full Text Available The introduction, establishment and spread of alien species is a major threat to biodiversity and the provision of ecosystem services for human wellbeing. In order to reduce further loss of biodiversity and maintain productive and sustainable ecosystems, understanding the ecological mechanisms underlying species invasions and avoiding potentially harmful effects on native communities is urgently needed, but largely lacking. We here demonstrate, by means of hydroacoustics and advanced spatial modelling, how native fish species as a result of previous exposure to native predators may successfully respond to invasive novel predators through a complicated game of hide and seek, minimizing spatio-temporal overlap with predators, and potentially facilitating coexistence between native prey species (Galaxiids and introduced novel predators (Salmonids in a deep Andean lake, Patagonia.

  20. Temperature-dependent performance of competitive native and alien invasive plant species

    Science.gov (United States)

    Song, Uhram

    2017-10-01

    To assess the likely impacts of environmental change, the responses of two well-known invasive plant species, native Pueraria lobata and alien Humulus japonicus, to differences in growth temperature were studied in South Korea. Habitat preferences, physiological responses such as photosynthetic rates and chlorophyll contents, growth rates, and nutrient contents were quantified for each species. A competition experiment was conducted to evaluate the temperature preferences of the two species. All results indicated that the alien species H. japonicus can take advantage of elevated temperatures (35 °C) to enhance its competitive advantage against the native species P. lobata. While H. japonicus took advantage of elevated temperatures and preferred high-temperature areas, P. lobata showed reduced performance and dominance in high-temperature areas. Therefore, in future, due to global warming and urbanization, there are possibilities that H. japonicus takes advantage of elevated temperature against P. lobata that could lead to increased H. japonicus coverage over time. Therefore, consistent monitoring of both species especially where P. lobata is dominated are required because both species are found in every continents in the world. Controlling P. lobata requires thorough inspection of H. japonicus presence of the habitat in advance to prevent post P. lobata management invasion of H. japonicus.

  1. The Impact of the Invasive Alien Plant, Impatiens glandulifera, on Pollen Transfer Networks.

    Directory of Open Access Journals (Sweden)

    Carine Emer

    Full Text Available Biological invasions are a threat to the maintenance of ecological processes, including pollination. Plant-flower visitor networks are traditionally used as a surrogated for pollination at the community level, despite they do not represent the pollination process, which takes place at the stigma of plants where pollen grains are deposited. Here we investigated whether the invasion of the alien plant Impatiens glandulifera (Balsaminaceae affects pollen transfer at the community level. We asked whether more alien pollen is deposited on the stigmas of plants on invaded sites, whether deposition is affected by stigma type (dry, semidry and wet and whether the invasion of I. glandulifera changes the structure of the resulting pollen transfer networks. We sampled stigmas of plants on 10 sites invaded by I. glandulifera (hereafter, balsam and 10 non-invaded control sites. All 20 networks had interactions with balsam pollen, although significantly more balsam pollen was found on plants with dry stigmas in invaded areas. Balsam pollen deposition was restricted to a small subset of plant species, which is surprising because pollinators are known to carry high loads of balsam pollen. Balsam invasion did not affect the loading of native pollen, nor did it affect pollen transfer network properties; networks were modular and poorly nested, both of which are likely to be related to the specificity of pollen transfer interactions. Our results indicate that pollination networks become more specialized when moving from the flower visitation to the level of pollen transfer networks. Therefore, caution is needed when inferring pollination from patterns of insect visitation or insect pollen loads as the relationship between these and pollen deposition is not straightforward.

  2. Tracking Invasive Alien Species (TrIAS: Building a data-driven framework to inform policy

    Directory of Open Access Journals (Sweden)

    Sonia Vanderhoeven

    2017-05-01

    Full Text Available Imagine a future where dynamically, from year to year, we can track the progression of alien species (AS, identify emerging problem species, assess their current and future risk and timely inform policy in a seamless data-driven workflow. One that is built on open science and open data infrastructures. By using international biodiversity standards and facilities, we would ensure interoperability, repeatability and sustainability. This would make the process adaptable to future requirements in an evolving AS policy landscape both locally and internationally. In recent years, Belgium has developed decision support tools to inform invasive alien species (IAS policy, including information systems, early warning initiatives and risk assessment protocols. However, the current workflows from biodiversity observations to IAS science and policy are slow, not easily repeatable, and their scope is often taxonomically, spatially and temporally limited. This is mainly caused by the diversity of actors involved and the closed, fragmented nature of the sources of these biodiversity data, which leads to considerable knowledge gaps for IAS research and policy. We will leverage expertise and knowledge from nine former and current BELSPO projects and initiatives: Alien Alert, Invaxen, Diars, INPLANBEL, Alien Impact, Ensis, CORDEX.be, Speedy and the Belgian Biodiversity Platform. The project will be built on two components: 1 The establishment of a data mobilization framework for AS data from diverse data sources and 2 the development of data-driven procedures for risk evaluation based on risk modelling, risk mapping and risk assessment. We will use facilities from the Global Biodiversity Information Facility (GBIF, standards from the Biodiversity Information Standards organization (TDWG and expertise from Lifewatch to create and facilitate a systematic workflow. Alien species data will be gathered from a large set of regional, national and international

  3. Evidence, Perceptions, and Trade-offs Associated with Invasive Alien Plant Control in the Table Mountain National Park, South Africa

    Directory of Open Access Journals (Sweden)

    Brian W. van Wilgen

    2012-06-01

    Full Text Available The Table Mountain National Park is a 265 km2 protected area embedded within a city of 3.5 million people. The park contains an extremely diverse flora with many endemic species, and has been granted World Heritage Site status in recognition of this unique biodiversity. Invasive alien plants are arguably the most significant threat to the conservation of this biodiversity, and the past decade has seen the implementation of aggressive programs aimed at the removal of invasions by these plants. These invasive alien plants include several species of trees, notably pines (Pinus species and eucalypts (Eucalyptus species, which historically have been grown in plantations, and which are utilized for recreation by the city's residents. In addition, many citizens regard the trees as attractive and ecologically beneficial, and for these reasons the alien plant control programs have been controversial. I briefly outline the legal obligations to deal with invasive alien plants, the history of control operations and the scientific rationale for their implementation, and the concerns that have been raised about the operations. Evidence in support of control includes the aggressive invasive nature of many species, and the fact that they displace native biodiversity (often irreversibly and have negative impacts on hydrology, fire intensity, and soil stability. Those against control cite aesthetic concerns, the value of pine plantations for recreation, the (perceived unattractive nature of the treeless natural vegetation, and the (incorrect belief that trees bring additional rainfall. The debate has been conducted through the press, and examples of perceptions and official responses are given. Despite opposition, the policy promoting alien plant removal has remained in place, and considerable progress has been made towards clearing pine plantations and invasive populations. This conservation success story owes much to political support, arising largely from job

  4. Resilience to disturbance and resistance to alien grass invasions in the cold desert of western North America

    Science.gov (United States)

    Alien grass invasions are resulting in ecosystem-level transformations of entire landscapes in arid and semi-arid ecosystems. The cold desert of western US is undergoing such a transformation, and is considered one of the most imperiled large ecosystems in the US. To address the rapid and complex ch...

  5. Proposed classification of invasive alien plant species in South Africa: towards prioritizing species and areas for management action

    CSIR Research Space (South Africa)

    Nel, JL

    2004-01-01

    Full Text Available the objective derivation of two lists of invasive alien plants in South Africa, using available quantitative data and expert knowledge on current patterns of distribution and abundance, life-history traits, and (for emerging invaders) estimates of potential...

  6. EU Regulation 1143/2014 and the Bern Convention : Allied forces in the war on invasive alien species

    NARCIS (Netherlands)

    Trouwborst, Arie

    This article identifies and analyzes current and potential synergies between the new EU Regulation 1143/2014 on the prevention and management of the introduction and spread of invasive alien species on the one hand, and the Bern Convention on the Conservation of European Wildlife and Natural

  7. Alien and invasive woody species in the dunes of the Wadden Sea Island of Vlieland: a remote sensing approach

    NARCIS (Netherlands)

    Hantson, W.; Kooistra, L.; Slim, P.A.

    2010-01-01

    In this study we mapped (alien) invasive shrubs for management and conservation purposes. On the study site, the Wadden Sea Island of Vlieland, they are a serious treat for the quality of the grey dune habitat. We developed a remote sensing approach that delivers detailed and standardized maps of

  8. Invasive alien plants in Croatia as a threat to biodiversity of South-Eastern Europe: distributional patterns and range size.

    Science.gov (United States)

    Nikolić, Toni; Mitić, Božena; Milašinović, Boris; Jelaska, Sven D

    2013-02-01

    During the analysis of alien and invasive flora of Europe, as a threat to biodiversity, data for Croatia were missing. The aim of our research was to analyse distributional patterns and range size of all invasive alien plants (64) for the state area (57,000 km(2)). They were detected on 49% of the state territory, averaging five taxa per 35 km(2). The greatest number of invasive plants (>30 per grid cell) was recorded in the major urban centres, increasing in the south-east direction and reflecting positive correlation with temperature and negative with altitude. The most endangered areas are in the Mediterranean region, especially on islands. The number of invasive plants increased with habitat diversity and almost 75% of all sites with invasive plants are located within a few habitats with direct anthropogenic influence. The results should provide a reliable regional and global basis for strategic planning regarding invasive alien plants management. Copyright © 2013 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  9. Separating habitat invasibility by alien plants from the actual level of invasion

    Czech Academy of Sciences Publication Activity Database

    Chytrý, M.; Jarošík, Vojtěch; Pyšek, Petr; Hájek, O.; Knollová, I.; Tichý, L.; Danihelka, Jiří

    2008-01-01

    Roč. 89, č. 6 (2008), s. 1541-1553 ISSN 0012-9658 R&D Projects: GA MŠk(CZ) LC06073 Grant - others:ALARM(XE) GOCE-CT-2003-506675 Institutional research plan: CEZ:AV0Z60050516 Keywords : archaeophyte * biological invasions * Central Europe Subject RIV: EF - Botanics Impact factor: 4.874, year: 2008

  10. Alien plants introduced by different pathways differ in invasion success: unintentional introductions as a threat to natural areas.

    Directory of Open Access Journals (Sweden)

    Petr Pyšek

    Full Text Available BACKGROUND: Understanding the dimensions of pathways of introduction of alien plants is important for regulating species invasions, but how particular pathways differ in terms of post-invasion success of species they deliver has never been rigorously tested. We asked whether invasion status, distribution and habitat range of 1,007 alien plant species introduced after 1500 A.D. to the Czech Republic differ among four basic pathways of introduction recognized for plants. PRINCIPAL FINDINGS: Pathways introducing alien species deliberately as commodities (direct release into the wild; escape from cultivation result in easier naturalization and invasion than pathways of unintentional introduction (contaminant of a commodity; stowaway arriving without association with it. The proportion of naturalized and invasive species among all introductions delivered by a particular pathway decreases with a decreasing level of direct assistance from humans associated with that pathway, from release and escape to contaminant and stowaway. However, those species that are introduced via unintentional pathways and become invasive are as widely distributed as deliberately introduced species, and those introduced as contaminants invade an even wider range of seminatural habitats. CONCLUSIONS: Pathways associated with deliberate species introductions with commodities and pathways whereby species are unintentionally introduced are contrasting modes of introductions in terms of invasion success. However, various measures of the outcome of the invasion process, in terms of species' invasion success, need to be considered to accurately evaluate the role of and threat imposed by individual pathways. By employing various measures we show that invasions by unintentionally introduced plant species need to be considered by management as seriously as those introduced by horticulture, because they invade a wide range of seminatural habitats, hence representing even a greater

  11. INVASIVE ALIEN PLANT SPECIES USED FOR THE TREATMENT OF VARIOUS DISEASES IN LIMPOPO PROVINCE, SOUTH AFRICA.

    Science.gov (United States)

    Maema, Lesibana Peter; Potgieter, Martin; Mahlo, Salome Mamokone

    2016-01-01

    Invasive alien plant species (IAPs) are plants that have migrated from one geographical region to non-native region either intentional or unintentional. The general view of IAPs in environment is regarded as destructive to the ecosystem and they pose threat to native vegetation and species. However, some of these IAPS are utilized by local inhabitants as a substitute for scarce indigenous plants. The aim of the study is to conduct ethnobotanical survey on medicinal usage of invasive plant species in Waterberg District, Limpopo Province, South Africa. An ethnobotanical survey on invasive plant species was conducted to distinguish species used for the treatment of various ailments in the Waterberg, District in the area dominated by Bapedi traditional healers. About thirty Bapedi traditional healers (30) were randomly selected via the snowball method. A guided field work by traditional healers and a semi-structured questionnaire was used to gather information from the traditional healers. The questionnaire was designed to gather information on the local name of plants, plant parts used and methods of preparation which is administered by the traditional healers. The study revealed that Schinus molle L., Catharanthus roseus (L.), Datura stramonium L., Opuntia stricta (Haw.) Haw., Opuntia ficus- indica, Sambucus canadensis L., Ricinus communis L., Melia azedarch L., Argemone ochroleuca and Eriobotrya japónica are used for treatment of various diseases such as chest complaint, blood purification, asthma, hypertension and infertility. The most plant parts that were used are 57.6% leaves, followed by 33.3% roots, and whole plant, seeds and bark at 3% each. Noticeably, most of these plants are cultivated (38%), followed by 28% that are common to the study area, 20% abundant, 12% wild, and 3% occasionally. Schinus molle is the most frequently used plant species for the treatment of various ailments in the study area. National Environmental Management Biodiversity Act (NEMBA

  12. Effects of invasive alien kahili ginger (Hedychium gardnerianum) on native plant species regeneration in a Hawaiian rainforest

    Science.gov (United States)

    Minden, V.; Jacobi, J.D.; Porembski, S.; Boehmer, H.J.

    2010-01-01

    Questions: Does the invasive alien Hedychium gardnerianum (1) replace native understory species, (2) suppress natural regeneration of native plant species, (3) increase the invasiveness of other non-native plants and (4) are native forests are able to recover after removal of H. gardnerianum. Location: A mature rainforest in Hawai'i Volcanoes National Park on the island of Hawai'i (about 1200 m. a.s.l.; precipitation approximately 2770mm yr-1). Study sites included natural plots without effects of alien plants, ginger plots with a H. gardnerianum-domimted herb layer and cleared plots treated with herbicide to remove alien plants. Methods: Counting mature trees, saplings and seedlings of native and alien plant species. Using nonparametric H-tests to compare impact of H. gardnerianum on the structure of different sites. Results: Results confirmed the hypothesis that H. gardnerianum has negative effects on natural forest dynamics. Lower numbers of native tree seedlings and saplings were found on ginger-dominated plots. Furthermore, H. gardnerianum did not show negative effects on the invasive alien tree species Psidium cattleianum. Conclusions: This study reveals that where dominance of H. gardnerianum persists, regeneration of the forest by native species will be inhibited. Furthermore, these areas might experience invasion by P. cattleianum, resulting in displacement of native canopy species in the future, leading to a change in forest structure and loss of other species dependent on natural rainforest, such as endemic birds. However, if H. gardnerianum is removed the native Hawaiian forest is likely to regenerate and regain its natural structure. ?? 2009 International Association for Vegetation Science.

  13. Chemical cues released by an alien invasive aquatic gastropod drive its invasion success.

    Science.gov (United States)

    Raw, Jacqueline L; Miranda, Nelson A F; Perissinotto, Renzo

    2013-01-01

    Chemical cues provide aquatic organisms with sensory information that guides behavioural responses and thus interactions among themselves, each other and the environment. Chemical cues are considered important for predator avoidance, foraging, larval settlement and broadcast spawning in aquatic environments. However, the significance of their role as drivers of direct interactions between heterospecifics has been largely overlooked. A video camera and a demarcated arena were used in situ to record behavioural responses of three native gastropod species, Assiminea cf. capensis, Melanoides tuberculata and Coriandria durbanensis, exposed to treatments representing chemical cues released by a non-native invasive gastropod, Tarebia granifera. The responses were measured quantitatively as displacement and orientation of movement at locations in St Lucia Estuary, within the iSimangaliso Wetland Park, a UNESCO World Heritage Site on the east coast of South Africa. All native gastropods exhibited a negative taxis response to chemical cues released by T. granifera, while T. granifera individuals responded randomly to conspecifics. Displacement was measured relative to the source of the extract, the number of steps taken were determined with path analysis and orientation was determined from the mean (±95% CIs) turning angles, with significant negative turning angles representing negative taxis. Responses to treatments corresponding to the environment and conspecifics were random and undirected, indicating kinesis. This study presents evidence for interactions driven by chemical cues between a non-native invasive gastropod and several gastropods native to South Africa. The results indicate that chemical cues can facilitate invasion success as the behavioural response of native gastropods is to move away allowing additional food and space resources to become available to T. granifera.

  14. Chemical cues released by an alien invasive aquatic gastropod drive its invasion success.

    Directory of Open Access Journals (Sweden)

    Jacqueline L Raw

    Full Text Available BACKGROUND: Chemical cues provide aquatic organisms with sensory information that guides behavioural responses and thus interactions among themselves, each other and the environment. Chemical cues are considered important for predator avoidance, foraging, larval settlement and broadcast spawning in aquatic environments. However, the significance of their role as drivers of direct interactions between heterospecifics has been largely overlooked. METHODOLOGY/PRINCIPAL FINDINGS: A video camera and a demarcated arena were used in situ to record behavioural responses of three native gastropod species, Assiminea cf. capensis, Melanoides tuberculata and Coriandria durbanensis, exposed to treatments representing chemical cues released by a non-native invasive gastropod, Tarebia granifera. The responses were measured quantitatively as displacement and orientation of movement at locations in St Lucia Estuary, within the iSimangaliso Wetland Park, a UNESCO World Heritage Site on the east coast of South Africa. All native gastropods exhibited a negative taxis response to chemical cues released by T. granifera, while T. granifera individuals responded randomly to conspecifics. Displacement was measured relative to the source of the extract, the number of steps taken were determined with path analysis and orientation was determined from the mean (±95% CIs turning angles, with significant negative turning angles representing negative taxis. Responses to treatments corresponding to the environment and conspecifics were random and undirected, indicating kinesis. CONCLUSION/SIGNIFICANCE: This study presents evidence for interactions driven by chemical cues between a non-native invasive gastropod and several gastropods native to South Africa. The results indicate that chemical cues can facilitate invasion success as the behavioural response of native gastropods is to move away allowing additional food and space resources to become available to T. granifera.

  15. Modeling invasive alien plant species in river systems: Interaction with native ecosystem engineers and effects on hydro-morphodynamic processes

    Science.gov (United States)

    van Oorschot, M.; Kleinhans, M. G.; Geerling, G. W.; Egger, G.; Leuven, R. S. E. W.; Middelkoop, H.

    2017-08-01

    Invasive alien plant species negatively impact native plant communities by out-competing species or changing abiotic and biotic conditions in their introduced range. River systems are especially vulnerable to biological invasions, because waterways can function as invasion corridors. Understanding interactions of invasive and native species and their combined effects on river dynamics is essential for developing cost-effective management strategies. However, numerical models for simulating long-term effects of these processes are lacking. This paper investigates how an invasive alien plant species affects native riparian vegetation and hydro-morphodynamics. A morphodynamic model has been coupled to a dynamic vegetation model that predicts establishment, growth and mortality of riparian trees. We introduced an invasive alien species with life-history traits based on Japanese Knotweed (Fallopia japonica), and investigated effects of low- and high propagule pressure on invasion speed, native vegetation and hydro-morphodynamic processes. Results show that high propagule pressure leads to a decline in native species cover due to competition and the creation of unfavorable native colonization sites. With low propagule pressure the invader facilitates native seedling survival by creating favorable hydro-morphodynamic conditions at colonization sites. With high invader abundance, water levels are raised and sediment transport is reduced during the growing season. In winter, when the above-ground invader biomass is gone, results are reversed and the floodplain is more prone to erosion. Invasion effects thus depend on seasonal above- and below ground dynamic vegetation properties and persistence of the invader, on the characteristics of native species it replaces, and the combined interactions with hydro-morphodynamics.

  16. Perception and Understanding of Invasive Alien Species Issues by Nature Conservation and Horticulture Professionals in Belgium

    Science.gov (United States)

    Vanderhoeven, Sonia; Piqueray, Julien; Halford, Mathieu; Nulens, Greet; Vincke, Jan; Mahy, Grégory

    2011-03-01

    We conducted a survey to determine how two professional sectors in Belgium, horticulture professionals and nature reserve managers (those directly involved in conservation), view the issues associated with invasive plant species. We developed and utilized a questionnaire that addressed the themes of awareness, concept and use of language, availability of information, impacts and, finally, control and available solutions. Using co-inertia analyses, we tested to what extent the perception of invasive alien species (IAS) was dependent upon the perception of Nature in general. Only forty-two percent of respondent horticulture professionals and eighty-two percent of nature reserve managers had a general knowledge of IAS. Many individuals in both target groups nonetheless had an accurate understanding of the scientific issues. Our results therefore suggest that the manner in which individuals within the two groups view, or perceive, the IAS issue was more the result of lack of information than simply biased perceptions of target groups. Though IAS perceptions by the two groups diverged, they were on par with how they viewed Nature in general. The descriptions of IAS by participants converged with the ideas and concepts frequently found in the scientific literature. Both managers and horticulture professionals expressed a strong willingness to participate in programs designed to prevent the spread of, and damage caused by, IAS. Despite this, the continued commercial availability of many invasive species highlighted the necessity to use both mandatory and voluntary approaches to reduce their re-introduction and spread. The results of this study provide stakeholders and conservation managers with practical information on which communication and management strategies can be based.

  17. Perception and understanding of invasive alien species issues by nature conservation and horticulture professionals in Belgium.

    Science.gov (United States)

    Vanderhoeven, Sonia; Piqueray, Julien; Halford, Mathieu; Nulens, Greet; Vincke, Jan; Mahy, Grégory

    2011-03-01

    We conducted a survey to determine how two professional sectors in Belgium, horticulture professionals and nature reserve managers (those directly involved in conservation), view the issues associated with invasive plant species. We developed and utilized a questionnaire that addressed the themes of awareness, concept and use of language, availability of information, impacts and, finally, control and available solutions. Using co-inertia analyses, we tested to what extent the perception of invasive alien species (IAS) was dependent upon the perception of Nature in general. Only forty-two percent of respondent horticulture professionals and eighty-two percent of nature reserve managers had a general knowledge of IAS. Many individuals in both target groups nonetheless had an accurate understanding of the scientific issues. Our results therefore suggest that the manner in which individuals within the two groups view, or perceive, the IAS issue was more the result of lack of information than simply biased perceptions of target groups. Though IAS perceptions by the two groups diverged, they were on par with how they viewed Nature in general. The descriptions of IAS by participants converged with the ideas and concepts frequently found in the scientific literature. Both managers and horticulture professionals expressed a strong willingness to participate in programs designed to prevent the spread of, and damage caused by, IAS. Despite this, the continued commercial availability of many invasive species highlighted the necessity to use both mandatory and voluntary approaches to reduce their re-introduction and spread. The results of this study provide stakeholders and conservation managers with practical information on which communication and management strategies can be based.

  18. The application of the European strategy on invasive alien species: an example with introduced squirrels

    Directory of Open Access Journals (Sweden)

    Sandro Bertolino

    2005-06-01

    Full Text Available Abstract We assessed the cases of squirrel species already introduced into Italy inside the framework proposed by the European strategy on invasive alien species. We collected information on 9 introductions that originated 8 populations: 3 of grey squirrels (Sciurus carolinensis, 2 of Finlayson's squirrels (Callosciurus finlaysonii, and 3 of Siberian chip-munks (Eutamias sibiricus. Food opportunism and high reproductive rate may explain the high success rate in establishing new populations, even with a low propagule pressure. A negative impact on the red squirrel (Sciurus vulgaris and damage to forestry and manufactures have been recorded in the areas of introduction. Accordingly to the European strategy, Italy is called to build-up a rapid response system in order to avoid further releases of alien squirrels in the wild. Meanwhile these species must be considered as a priority for trade restriction. Considering the risks posed to biodiversity and human activities, Italy must adopt a precautionary principle, removing small nuclei of introduced species before they spread in large areas. Riassunto Applicazione della strategia europea sulle specie non indigene: un esempio con gli scoiattoli introdotti Come esempio di applicazione della strategia europea sulle specie invasive introdotte, abbiamo analizzato la situazione degli scoiattoli introdotti in Italia. Su 9 introduzioni registrate, in 8 casi si sono formate popolazioni naturalizzate: 3 di scoiattolo grigio (Sciurus carolinensis, 2 di scoiattolo di Finlayson (Callosciurus finlaysonii e 3 di tamia siberiano (Eutamias sibiricus. L'alto successo delle introduzioni, anche a partire da pochi animali rilasciati, è probabilmente legato all'opportunismo alimentare delle specie considerate e al loro elevato tasso riproduttivo. Al momento, nelle aree di introduzione sono segnalati fenomeni

  19. Citizen Science and Open Data: a model for Invasive Alien Species in Europe

    Directory of Open Access Journals (Sweden)

    Ana Cristina Cardoso

    2017-07-01

    Full Text Available Invasive Alien Species (IAS are a growing threat to Europe's biodiversity. The implementation of European Union Regulation on IAS can benefit from the involvement of the public in IAS recording and management through Citizen Science (CS initiatives. Aiming to tackle issues related with the use of CS projects on IAS topics, a dedicated workshop titled “Citizen Science and Open Data: a model for Invasive Alien Species in Europe” was organized by the Joint Research Centre (JRC and the European Cooperation in Science and Technology (COST Association. Fifty key stakeholders from all Europe, including two Members of the European Parliament, attended the workshop. With a clear focus on IAS, the workshop aimed at addressing the following issues: a CS and policy, b citizen engagement, and c CS data management. Nine short presentations provided input on CS and IAS issues. Participants discussed specific topics in several round tables (“world café” style and reported back their conclusions to the audience and full assembly moderated discussions. Overall, the workshop enabled the sharing of ideas, approaches and best practices regarding CS and IAS. Specific opportunities and pitfalls of using CS data in the whole policy cycle for IAS were recognized. Concerning the implementation of the IAS Regulation, CS data could complement official surveillance systems, and contribute to the early warning of the IAS of Union concern after appropriate validation by the Member States’ competent authorities. CS projects can additionally increase awareness and empower citizens. Attendees pointed out the importance for further public engagement in CS projects on IAS that demonstrate specific initiatives and approaches and analyze lessons learned from past experiences. In addition, the workshop noted that the data gathered from different CS projects on IAS are fragmented. It highlighted the need for using an open and accessible platform to upload data originating

  20. Invasion by the Alien Tree Prunus serotina Alters Ecosystem Functions in a Temperate Deciduous Forest

    Science.gov (United States)

    Aerts, Raf; Ewald, Michael; Nicolas, Manuel; Piat, Jérôme; Skowronek, Sandra; Lenoir, Jonathan; Hattab, Tarek; Garzón-López, Carol X.; Feilhauer, Hannes; Schmidtlein, Sebastian; Rocchini, Duccio; Decocq, Guillaume; Somers, Ben; Van De Kerchove, Ruben; Denef, Karolien; Honnay, Olivier

    2017-01-01

    Alien invasive species can affect large areas, often with wide-ranging impacts on ecosystem structure, function, and services. Prunus serotina is a widespread invader of European temperate forests, where it tends to form homogeneous stands and limits recruitment of indigenous trees. We hypotesized that invasion by P. serotina would be reflected in the nutrient contents of the native species' leaves and in the respiration of invaded plots as efficient resource uptake and changes in nutrient cycling by P. serotina probably underly its aggressive invasiveness. We combined data from 48 field plots in the forest of Compiègne, France, and data from an experiment using 96 microcosms derived from those field plots. We used general linear models to separate effects of invasion by P. serotina on heterotrophic soil and litter respiration rates and on canopy foliar nutrient content from effects of soil chemical properties, litter quantity, litter species composition, and tree species composition. In invaded stands, average respiration rates were 5.6% higher for soil (without litter) and 32% higher for soil and litter combined. Compared to indigenous tree species, P. serotina exhibited higher foliar N (+24.0%), foliar P (+50.7%), and lower foliar C:N (−22.4%) and N:P (−10.1%) ratios. P. serotina affected foliar nutrient contents of co-occuring indigenous tree species leading to decreased foliar N (−8.7 %) and increased C:N ratio (+9.5%) in Fagus sylvatica, decreased foliar N:P ratio in Carpinus betulus (−13.5%) and F. sylvatica (−11.8%), and increased foliar P in Pinus sylvestris (+12.3%) in invaded vs. uninvaded stands. Our results suggest that P. serotina is changing nitrogen, phosphorus, and carbon cycles to its own advantage, hereby increasing carbon turnover via labile litter, affecting the relative nutrient contents in the overstory leaves, and potentially altering the photosynthetic capacity of the long-lived indigenous broadleaved species. Uncontrolled

  1. Ecological effects of invasive alien species on native communities, with particular emphasis on the interactions between aphids and ladybirds

    Czech Academy of Sciences Publication Activity Database

    Kindlmann, Pavel; Ameixa, Olga; Dixon, Anthony F. G.

    2011-01-01

    Roč. 56, č. 4 (2011), s. 469-476 ISSN 1386-6141 R&D Projects: GA MŠk LC06073; GA MŠk(CZ) ED1.1.00/02.0073 Institutional research plan: CEZ:AV0Z60870520 Keywords : invasive alien species * predators * insect pest s * ecological effects * intraguild predation Subject RIV: EH - Ecology, Behaviour Impact factor: 1.927, year: 2011

  2. Does governance play a role in the distribution of invasive alien species?

    Science.gov (United States)

    Evans, Thomas; Zu Ermgassen, Philine; Amano, Tatsuya; Peh, Kelvin S-H

    2018-02-01

    Invasive alien species (IAS) constitute a major threat to global biological diversity. In order to control their spread, a detailed understanding of the factors influencing their distribution is essential. Although international trade is regarded as a major force structuring spatial patterns of IAS, the role of other social factors remains unclear. Despite studies highlighting the importance of strong governance in slowing drivers of biodiversity loss such as logging, deforestation, and agricultural intensification, no study has yet analyzed its contribution to the issue of IAS. Using estimates of governance quality and comprehensive spatiotemporal IAS data, we performed multiple linear regressions to investigate the effect of governance quality upon the distribution of species listed under "100 of the worst" IAS in 38 Eurasian countries as defined by DASIE. Our model suggested that for countries with higher GDP, stronger governance was associated with a greater number of the worst IAS; in contrast, for the lowest GDP countries under analysis, stronger governance was associated with fewer of these IAS. We elucidate how the quality of governance within a country has implications for trade, tourism, transport, legislation, and economic development, all of which influence the spread of IAS. While our findings support the common assumption that strengthening governance benefits conservation interventions in countries of smaller economy, we find that this effect is not universal. Stronger governance alone cannot adequately address the problem of IAS, and targeted action is required in relatively high-GDP countries in order to stem the influx of IAS associated with high volumes of trade.

  3. Determining the feasibility of harvesting invasive alien plant species for energy

    Directory of Open Access Journals (Sweden)

    Worship Mugido

    2014-11-01

    Full Text Available Woody invasive alien plants (IAPs are a threat to South Africa's water resources, biodiversity and land productivity. The impacts of IAPs were the main reason for the South African government to embark on a natural resource management public works programme called Working for Water (WfW, which was aimed at controlling IAPs in a cost-effective yet labour-intensive way. At the same time, the high biomass of these species presents opportunities for synergies between the clearing of IAPs and the generation of biomass-based energy. The purpose of this study was to determine the cost of harvesting and extracting, chipping, and transporting the biomass, and also to determine the financial and economic feasibility of such an exercise from a commercial perspective. Sampling of the biomass was done at 31 representative sites within the Nelson Mandela Metropolitan Municipality, South Africa. The cost of the operation was carefully monitored, documented and reported at each stage, and compared to the cost of replacing the thermal coal currently used by industry within this municipality. The project proved to be financially viable, but only when the energy entrepreneur forms a partnership with the WfW programme, and then only under specific conditions. The project has, however, very high socio-economic returns with respect to a reduction in environmental externalities and job creation.

  4. Effect of the alien invasive bivalve Corbicula fluminea on the nutrient dynamics under climate change scenarios

    Science.gov (United States)

    Coelho, J. P.; Lillebø, A. I.; Crespo, D.; Leston, S.; Dolbeth, M.

    2018-05-01

    The main aim of this study was to evaluate the impact of the alien invasive bivalve Corbicula fluminea (Müller, 1774) in the nutrient dynamics of temperate estuarine systems (oligohaline areas) under climate change scenarios. The scenarios simulated shifts in climatic conditions, following salinity (0 or 5) and temperature (24 or 30 °C) changes, usual during drought and heat wave events. The effect of the individual size/age (different size classes with fixed biomass) and density (various densities of <1 cm clams) on the bioturbation-associated nutrient dynamics were also evaluated under an 18-day laboratory experimental setup. Results highlight the significant effect of C. fluminea on the ecosystem nutrient dynamics, enhancing the efflux of both phosphate and dissolved inorganic nitrogen (DIN) from the sediments to the water column. Both drought and heat wave events will have an impact on the DIN dynamics within C. fluminea colonized systems, favouring a higher NH4-N efflux. The population structure of C. fluminea will have a decisive role on the impact of the species, with stronger nutrient effluxes associated with a predominantly juvenile population structure.

  5. Seed dispersal networks in the Galápagos and the consequences of alien plant invasions

    DEFF Research Database (Denmark)

    Heleno, R. H.; Olesen, Jens Mogens; Nogales, M.

    2013-01-01

    , followed by small ground finch, two mockingbirds, the giant tortoise and two insectivorous birds. Most animals dispersed alien seeds, but these formed a relatively small proportion of the interactions. Nevertheless, the integration of aliens was higher in the island that has been invaded for longest...

  6. Assessment and prediction of the invasiveness of some alien plants in conditions of climate change in the steppe Dnieper region

    Directory of Open Access Journals (Sweden)

    Y. V. Lykholat

    2017-02-01

    Full Text Available The flora of the steppe Dnieper region is characterized by an abundance of naturalized alien species, some of which colonised over the last decade. Climate change, associated primarily with increasing temperature, became clearly manifested in this period. We tested the hypothesis that there is an association between climate change and the initiation of invasiveness of some alien plant species in the steppe Dnieper region. For this purpose, comparative studies of the distribution boundaries of naturalized alien trees, shrubs and herbaceous plants were conducted. Along the research route numerous 5–10-year-old broadleaf linden trees (Tilia platyphyllos Scop. were found in the man-made plantation communities of Dnipro city in areas with moist soil; seeded undergrowth was located at a significant distance from the adult linden plants. Numerous groups of young 7–10-year-old plants of the smoke trees (Cotinus coggygria Scop., which had a seed origin, were found in the shelterbelt and urban recreational plantations. Young 10–12-year-old virginal and generative plants of the black cherry (Padus serotina Ehrh. were found in large numbers in both the semi-natural and artificial plant communities at great distances from the adult trees. The alien plant species common hackberry (Celtis occidentalis L. showed the ability to form fairly sparse seminal seedlings, which was presented by the plants at the age of 4–7 years in both the natural and urban plant communities. The perennial herbaceous plant common milkweed (Asclepias syriaca L. was found in the course of the research in ruderal habitats, urban plant communities, and also in the agrocoenoses. The common milkweed reached its greatest abundance in fields of winter crops, where the spread of this species was accompanied by a sharp decrease in the number of other species of segetal plants. Our study results confirm that the extension of the distribution boundaries of alien species over the last

  7. Horizon scanning for invasive alien species with the potential to threaten biodiversity in Great Britain.

    Science.gov (United States)

    Roy, Helen E; Peyton, Jodey; Aldridge, David C; Bantock, Tristan; Blackburn, Tim M; Britton, Robert; Clark, Paul; Cook, Elizabeth; Dehnen-Schmutz, Katharina; Dines, Trevor; Dobson, Michael; Edwards, François; Harrower, Colin; Harvey, Martin C; Minchin, Dan; Noble, David G; Parrott, Dave; Pocock, Michael J O; Preston, Chris D; Roy, Sugoto; Salisbury, Andrew; Schönrogge, Karsten; Sewell, Jack; Shaw, Richard H; Stebbing, Paul; Stewart, Alan J A; Walker, Kevin J

    2014-12-01

    Invasive alien species (IAS) are considered one of the greatest threats to biodiversity, particularly through their interactions with other drivers of change. Horizon scanning, the systematic examination of future potential threats and opportunities, leading to prioritization of IAS threats is seen as an essential component of IAS management. Our aim was to consider IAS that were likely to impact on native biodiversity but were not yet established in the wild in Great Britain. To achieve this, we developed an approach which coupled consensus methods (which have previously been used for collaboratively identifying priorities in other contexts) with rapid risk assessment. The process involved two distinct phases: Preliminary consultation with experts within five groups (plants, terrestrial invertebrates, freshwater invertebrates, vertebrates and marine species) to derive ranked lists of potential IAS. Consensus-building across expert groups to compile and rank the entire list of potential IAS. Five hundred and ninety-one species not native to Great Britain were considered. Ninety-three of these species were agreed to constitute at least a medium risk (based on score and consensus) with respect to them arriving, establishing and posing a threat to native biodiversity. The quagga mussel, Dreissena rostriformis bugensis, received maximum scores for risk of arrival, establishment and impact; following discussions the unanimous consensus was to rank it in the top position. A further 29 species were considered to constitute a high risk and were grouped according to their ranked risk. The remaining 63 species were considered as medium risk, and included in an unranked long list. The information collated through this novel extension of the consensus method for horizon scanning provides evidence for underpinning and prioritizing management both for the species and, perhaps more importantly, their pathways of arrival. Although our study focused on Great Britain, we suggest

  8. Conserving a geographically isolated Charaxes butterfly in response to habitat fragmentation and invasive alien plants

    Directory of Open Access Journals (Sweden)

    Casparus J. Crous

    2015-03-01

    Full Text Available In South Africa, much of the forest biome is vulnerable to human-induced disturbance. The forest-dwelling butterfly Charaxes xiphares occidentalis is naturally confined to a small forest region in the south-western Cape, South Africa. Most of the remaining habitat of this species is within a fragmented agricultural matrix. Furthermore, this geographical area is also heavily invaded by alien plants, especially Acacia mearnsii. We investigated how C. x. occidentalis behaviourally responds to different habitat conditions in the landscape. We were particularly interested in touring, patrolling and settling behaviour as a conservation proxy for preference of a certain habitat configuration in this agricultural matrix. Remnant forest patches in the agricultural matrix showed fewer behavioural incidents than in a reference protected area. Moreover, dense stands of A. mearnsii negatively influenced the incidence and settling pattern of this butterfly across the landscape, with fewer tree settlings associated with more heavily invaded forest patches. This settling pattern was predominantly seen in female butterflies. We also identified specific trees that were settled upon for longer periods by C. x. occidentalis. Distance to a neighbouring patch and patch size influenced behavioural incidences, suggesting that further patch degradation and isolation could be detrimental to this butterfly. Conservation implications: We highlight the importance of clearing invasive tree species from vulnerable forest ecosystems and identify key tree species to consider in habitat conservation and rehabilitation programmes for this butterfly. We also suggest retaining as much intact natural forest as possible. This information should be integrated in local biodiversity management plans.

  9. Conserving a geographically isolated Charaxes butterfly in response to habitat fragmentation and invasive alien plants

    Directory of Open Access Journals (Sweden)

    Casparus J. Crous

    2015-08-01

    Full Text Available In South Africa, much of the forest biome is vulnerable to human-induced disturbance. The forest-dwelling butterfly Charaxes xiphares occidentalis is naturally confined to a small forest region in the south-western Cape, South Africa. Most of the remaining habitat of this species is within a fragmented agricultural matrix. Furthermore, this geographical area is also heavily invaded by alien plants, especially Acacia mearnsii. We investigated how C. x. occidentalis behaviourally responds to different habitat conditions in the landscape. We were particularly interested in touring, patrolling and settling behaviour as a conservation proxy for preference of a certain habitat configuration in this agricultural matrix. Remnant forest patches in the agricultural matrix showed fewer behavioural incidents than in a reference protected area. Moreover, dense stands of A. mearnsii negatively influenced the incidence and settling pattern of this butterfly across the landscape, with fewer tree settlings associated with more heavily invaded forest patches. This settling pattern was predominantly seen in female butterflies. We also identified specific trees that were settled upon for longer periods by C. x. occidentalis. Distance to a neighbouring patch and patch size influenced behavioural incidences, suggesting that further patch degradation and isolation could be detrimental to this butterfly. Conservation implications: We highlight the importance of clearing invasive tree species from vulnerable forest ecosystems and identify key tree species to consider in habitat conservation and rehabilitation programmes for this butterfly. We also suggest retaining as much intact natural forest as possible. This information should be integrated in local biodiversity management plans.

  10. Biological invasions: economic and environmental costs of alien plant, animal, and microbe species

    National Research Council Canada - National Science Library

    Pimentel, David

    2011-01-01

    ...: Economic and Environmental Costs of Alien Plant, Animal, and Microbe Species, this reference discusses how non-native species invade new ecosystems and the subsequent economic and environmental effects of these species...

  11. DEVELOPMENT OF AN INDEX OF ALIEN SPECIES INVASIVENESS: AN AID TO ASSESSING RIPARIAN VEGETATION CONDITION

    Science.gov (United States)

    Many riparian areas are invaded by alien plant species that negatively affect native species composition, community dynamics and ecosystem properties. We sampled vegetation along reaches of 31 low order streams in eastern Oregon, and characterized species assemblages at patch an...

  12. Suitability of the ALien Biotic IndEX (ALEX) for assessing invasion of macroalgae across different Mediterranean habitats.

    Science.gov (United States)

    Piazzi, Luigi; Gennaro, Paola; Ceccherelli, Giulia

    2015-08-15

    The ALien Biotic IndEX (ALEX) has been recently proposed to evaluate biological invasions in soft-bottom macro-invertebrate assemblages. The present paper proposes the use of ALEX in sessile assemblages of Mediterranean hard bottom habitats and tests it along gradients of invasion. For five invasive macroalgae a variable number of case studies per each of four habitats were examined from the available data sets. For each case study samples were attributed to four levels of invasion depending on the abundance of the invading macroalgae. Results showed that the application of ALEX to sessile assemblages of hard bottoms allows to qualify the level of invasion along the considered gradients. Moreover, the decline of index values matched the impact of invasion on species number of the assemblages. Results also suggest that the concurrent use of ALEX and indices of benthic quality status can be a valuable tool to assess biopollution in hard bottom habitats. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. EventSlider User Manual

    Science.gov (United States)

    2016-09-01

    PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) September 2016 2. REPORT TYPE Technical Report 3. DATES...through the LineColor property. This property is a WPF Brush object. As a WPF Brush object, one will commonly use a SolidColorBrush, but gradient... brushes , for example, could be used for other visual effects. This brush is applied to all events that are visible on the slider. However, if the lines

  14. A preliminary assessment of the extent and potential impacts of alien plant invasions in the Serengeti-Mara ecosystem, East Africa

    Directory of Open Access Journals (Sweden)

    Arne B.R. Witt

    2017-01-01

    Full Text Available This article provides a preliminary list of alien plant species in the Serengeti-Mara ecosystem in East Africa. The list is based on broad-scale roadside surveys in the area and is supplemented by more detailed surveys of tourist facilities in the Masai-Mara National Reserve and adjoining conservancies. We encountered 245 alien plant species; significantly more than previous studies, of which 62 (25% were considered to have established self-perpetuating populations in areas away from human habitation. These included species which had either been intentionally or accidentally introduced. Of the 245 alien plants, 212 (including four species considered to be native to the region were intentionally introduced into gardens in the National Reserve and 51 (24% had established naturalised populations within the boundaries of these tourism facilities. Of the 51 naturalised species, 23 (11% of the 212 alien species were recorded as being invasive within the ecosystem, outside of lodges and away from other human habitation. Currently, the Serengeti-Mara ecosystem is relatively free of widespread and abundant invasive alien plants, with a few exceptions, but there are extensive populations outside of the ecosystem, particularly to the west, from where they could spread. We address the potential impacts of six species that we consider to pose the highest risks (Parthenium hysterophorus, Opuntia stricta, Tithonia diversifolia, Lantana camara, Chromolaena odorata and Prosopis juliflora. Although invasive alien plants pose substantial threats to the integrity of the ecosystem, this has not yet been widely recognised. We predict that in the absence of efforts to contain, or reverse the spread of invasive alien plants, the condition of rangelands will deteriorate, with severe negative impacts on migrating large mammals, especially wildebeest, zebra and gazelles. This will, in turn, have a substantial negative impact on tourism, which is a major economic activity

  15. What do we really know about alien plant invasion? A review of the invasion mechanism of one of the world's worst weeds.

    Science.gov (United States)

    Bajwa, Ali Ahsan; Chauhan, Bhagirath Singh; Farooq, Muhammad; Shabbir, Asad; Adkins, Steve William

    2016-07-01

    This review provides an insight into alien plant invasion taking into account the invasion mechanism of parthenium weed ( Parthenium hysterophorus L.). A multi-lateral understanding of the invasion biology of this weed has pragmatic implications for weed ecology and management. Biological invasions are one of the major drivers of restructuring and malfunctioning of ecosystems. Invasive plant species not only change the dynamics of species composition and biodiversity but also hinder the system productivity and efficiency in invaded regions. Parthenium weed, a well-known noxious invasive species, has invaded diverse climatic and biogeographic regions in more than 40 countries across five continents. Efforts are under way to minimize the parthenium weed-induced environmental, agricultural, social, and economic impacts. However, insufficient information regarding its invasion mechanism and interference with ecosystem stability is available. It is hard to devise effective management strategies without understanding the invasion process. Here, we reviewed the mechanism of parthenium weed invasion. Our main conclusions are: (1) morphological advantages, unique reproductive biology, competitive ability, escape from natural enemies in non-native regions, and a C3/C4 photosynthesis are all likely to be involved in parthenium weed invasiveness. (2) Tolerance to abiotic stresses and ability to grow in wide range of edaphic conditions are thought to be additional invasion tools on a physiological front. (3) An allelopathic potential of parthenium weed against crop, weed and pasture species, with multiple modes of allelochemical expression, may also be responsible for its invasion success. Moreover, the release of novel allelochemicals in non-native environments might have a pivotal role in parthenium weed invasion. (4) Genetic diversity found among different populations and biotypes of parthenium weed, based on geographic, edaphic, climatic, and ecological ranges, might also

  16. The Bifurcation and Control of a Single-Species Fish Population Logistic Model with the Invasion of Alien Species

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    2014-01-01

    Full Text Available The objective of this paper is to study systematically the bifurcation and control of a single-species fish population logistic model with the invasion of alien species based on the theory of singular system and bifurcation. It regards Spartina anglica as an invasive species, which invades the fisheries and aquaculture. Firstly, the stabilities of equilibria in this model are discussed. Moreover, the sufficient conditions for existence of the trans-critical bifurcation and the singularity induced bifurcation are obtained. Secondly, the state feedback controller is designed to eliminate the unexpected singularity induced bifurcation by combining harvested effort with the purification capacity. It obviously inhibits the switch of population and makes the system stable. Finally, the numerical simulation is proposed to show the practical significance of the bifurcation and control from the biological point of view.

  17. Alien and invasive species in plant communities of the Vistula and Brennica rivers gravel bars (Western Carpathians, Poland

    Directory of Open Access Journals (Sweden)

    Wilczek Zbigniew

    2015-06-01

    Full Text Available Gravel bars are the initial habitats, inseparably connected to the mountain streams. On the one hand, they are an unstable substrate, influenced by the overflows and high waters; however, they are also exposed to strong sunlight and heat. This situation determines specific vegetation which, due to dynamic changes in the habitat, has a pioneer character. What is more, gravel bars are areas where many river migratory species and many random species appear. Among them, there are also synanthropic species. In years 2011-2012, floristic and phytosociological studies were conducted in the Silesian Beskids. The goal of these studies was to recognize the vegetation of the gravel bars of the Vistula and the Brennica rivers - from their springs in the Silesian Beskids to the point where the Brennica River flows into the Vistula River in the Silesian Foothills. The studied section of the two rivers is regulated. Particular attention was paid to the synanthropic species that pose a threat to the native flora. In 9 recognized types of plant communities, 293 vascular plant species were recognized. More than 15% of the flora were alien species (45 and 22 of them were considered to be invasive. The most common invasive species that were spotted included: Impatiens glandulifera, Heracleum mantegazzianum and Reynoutria japonica. Plant communities with the biggest number and share of alien species were Plantago major-Barbarea vulgaris community and Phalaridetum arundinaceae.

  18. Invasive alien species in the food chain: Advancing risk assessment models to address climate change, economics and uncertainty

    Directory of Open Access Journals (Sweden)

    Darren Kriticos

    2013-09-01

    Full Text Available Pest risk maps illustrate where invasive alien arthropods, molluscs, pathogens, and weeds might become established, spread, and cause harm to natural and agricultural resources within a pest risk area. Such maps can be powerful tools to assist policymakers in matters of international trade, domestic quarantines, biosecurity surveillance, or pest-incursion responses. The International Pest Risk Mapping Workgroup (IPRMW is a group of ecologists, economists, modellers, and practising risk analysts who are committed to improving the methods used to estimate risks posed by invasive alien species to agricultural and natural resources. The group also strives to improve communication about pest risks to biosecurity, production, and natural-resource-sector stakeholders so that risks can be better managed. The IPRMW previously identified ten activities to improve pest risk assessment procedures, among these were: “improve representations of uncertainty, … expand communications with decision-makers on the interpretation and use of risk maps, … increase international collaboration, … incorporate climate change, … [and] study how human and biological dimensions interact” (Venette et al. 2010.

  19. Effects of alien woody plant invasion on the birds of Mountain ...

    African Journals Online (AJOL)

    1989-04-18

    Apr 18, 1989 ... alien A. cyclops is apparently enhanced by dispersal of the seeds by frugivorous birds (Glyphis, Milton & .... Friedman two-way analysis of variance by ranks (Con- over 1971) was used to assess the significance of ...... Towards a theory of continental species diversities: bird distributions over mediterranean ...

  20. Effects of alien woody plant invasion on the birds of Mountain ...

    African Journals Online (AJOL)

    The density, biomass, species richness and composition of birds in plots in two Mountain Fynbos plant-species assemblages (Tall Mixed Fynbos and Restionaceous Tussock Marsh), infested with alien woody plants (mainly Australian Acacia spp.) at the Cape of Good Hope Nature Reserve, South Africa, were compared ...

  1. Key elements towards a Joint Invasive Alien Species Strategy for the Dutch Caribbean

    NARCIS (Netherlands)

    Smith, S.R.; Burg, van der W.J.; Debrot, A.O.; Buurt, van G.; Freitas, de J.A.

    2014-01-01

    Recent inventories have documented no less than 211 exotic alien species in the wild for the Dutch Caribbean. These amount to no less than 27 introduced marine species, 65 introduced terrestrial plants, 72 introduced terrestrial and freshwater animals and 47 introduced agricultural pests and

  2. An assessment of alien invasive plant species in Gonarezhou National Park, Zimbabwe

    NARCIS (Netherlands)

    Sithole, D.; Zisadza-Gandiwa, P.; Gandiwa, E.

    2012-01-01

    This study investigated the occurrence of alien plant species in Gonarezhou National Park (GNP), Zimbabwe. We focused on two main habitat types, namely riparian areas of the major rivers and dry land areas. Sampling was carried out from 42 sampling plots in both habitat types. Variables studied

  3. Mapping invasive alien Acacia dealbata Link using ASTER multispectral imagery: a case study in central-eastern of Portugal

    Directory of Open Access Journals (Sweden)

    Filipe Martins

    2016-12-01

    Full Text Available Aim of the study: Acacia dealbata is an alien invasive species that is widely spread in Portugal. The main goal of this study was to produce an accurate and detailed map for this invasive species using ASTER multispectral imagery. Area of study: The central-eastern zone of Portugal was used as study area. This whole area is represented in an ASTER scene covering about 321.1 x 103 ha. Material and methods: ASTER imagery of two dates (flowering season and dry season were classified by applying three supervised classifiers (Maximum Likelihood, Support Vector Machine and Artificial Neural Networks to five different land cover classifications (from most generic to most detailed land cover categories. The spectral separability of the land cover categories was analyzed and the accuracy of the 30 produced maps compared. Main results: The highest classification accuracy for acacia mapping was obtained using the flowering season imagery, the Maximum Likelihood classifier and the most detailed land cover classification (overall accuracy of 86%; Kappa statistics of 85%; acacia class Kappa statistics of 100%. As a result, the area occupied by acacia was estimated to be approximated 24,770 ha (i.e. 8% of the study area. Research highlights: The methodology explored proved to be a cost-effective solution for acacia mapping in central-eastern of Portugal. The obtained map enables a more accurate and detailed identification of this species’ invaded areas due to its spatial resolution (minimum mapping unit of 0.02 ha providing a substantial improvement comparably to the existent national land cover maps to support monitoring and control activities. Keywords: remote sensing; invasive alien species; land cover mapping; vegetation mapping.

  4. Hydrodynamic Lubrication Analysis Of Slider Bearings Lubricated ...

    African Journals Online (AJOL)

    Hydrodynamic Lubrication Analysis Of Slider Bearings Lubricated With Micropolar Fluids. ... In this paper, a theoretical study of the effect of micropolar lubricants on the performance characteristics of wide inclined slider bearings is presented. The finite element method and Gauss Seidel iterative procedure have been used ...

  5. Reproductive biology and adaptability of the invasive alien freshwater Amphipod Crangonyx floridanus (Crustacea: Amphipoda, Crangonyctidae).

    Science.gov (United States)

    Tojo, Koji; Tanaka, Yoshiki; Kuranishi, Ryoichi B; Kanada, Shoji

    2010-06-01

    We studied the reproductive biology and adaptability of the alien freshwater crangonyctid amphipod Crangonyx floridanus, currently inhabiting a large portion of Japan, both in the field and under controlled laboratory conditions. In the Chikuma River population of this alien amphipod, egg-bearing individuals were found throughout the year. In terms of egg maturation cycle, egg development (during embryogenesis), and egg count per ovipositional cycle, these amphipods display a very efficient reproductive system. This study also established their adaptability to a wide range of water temperatures (primarily 4-20 degrees C, however in some cases, these individuals are able to survive at up to 30 degrees C). C. floridanus's strong capacity to adapt to broad and variable environmental conditions is certainly contributing to its high rate of population increase, and rapid dispersion throughout Japan.

  6. An extensive field survey combined with a phylogenetic analysis reveals rapid and widespread invasion of two alien whiteflies in China.

    Science.gov (United States)

    Hu, Jian; De Barro, Paul; Zhao, Hua; Wang, Jia; Nardi, Francesco; Liu, Shu-Sheng

    2011-01-21

    To understand the processes of invasions by alien insects is a pre-requisite for improving management. The whitefly Bemisia tabaci is a cryptic species complex that contains some of the most invasive pests worldwide. However, extensive field data to show the geographic distribution of the members of this species complex as well as the invasion by some of its members are scarce. We used field surveys and published data to assess the current diversity and distribution of B. tabaci cryptic species in China and relate the indigenous members to other Asian and Australian members of the complex. The survey covered the 16 provinces where indigenous B. tabaci occur and extends this with published data for the whole of China. We used molecular markers to identify cryptic species. The evolutionary relationships between the different Asian B. tabaci were reconstructed using Bayesian methods. We show that whereas in the past the exotic invader Middle East-Asia Minor 1 was predominant across China, another newer invader Mediterranean is now the dominant species in the Yangtze River Valley and eastern coastal areas, and Middle East-Asia Minor 1 is now predominant only in the south and south eastern coastal areas. Based on mtCO1 we identified four new cryptic species, and in total we have recorded 13 indigenous and two invasive species from China. Diversity was highest in the southern and southeastern provinces and declined to north and west. Only the two invasive species were found in the northern part of the country where they occur primarily in protected cropping. By 2009, indigenous species were mainly found in remote mountainous areas and were mostly absent from extensive agricultural areas. Invasions by some members of the whitefly B. tabaci species complex can be rapid and widespread, and indigenous species closely related to the invaders are replaced.

  7. An extensive field survey combined with a phylogenetic analysis reveals rapid and widespread invasion of two alien whiteflies in China.

    Directory of Open Access Journals (Sweden)

    Jian Hu

    Full Text Available BACKGROUND: To understand the processes of invasions by alien insects is a pre-requisite for improving management. The whitefly Bemisia tabaci is a cryptic species complex that contains some of the most invasive pests worldwide. However, extensive field data to show the geographic distribution of the members of this species complex as well as the invasion by some of its members are scarce. METHODOLOGY/PRINCIPAL FINDINGS: We used field surveys and published data to assess the current diversity and distribution of B. tabaci cryptic species in China and relate the indigenous members to other Asian and Australian members of the complex. The survey covered the 16 provinces where indigenous B. tabaci occur and extends this with published data for the whole of China. We used molecular markers to identify cryptic species. The evolutionary relationships between the different Asian B. tabaci were reconstructed using Bayesian methods. We show that whereas in the past the exotic invader Middle East-Asia Minor 1 was predominant across China, another newer invader Mediterranean is now the dominant species in the Yangtze River Valley and eastern coastal areas, and Middle East-Asia Minor 1 is now predominant only in the south and south eastern coastal areas. Based on mtCO1 we identified four new cryptic species, and in total we have recorded 13 indigenous and two invasive species from China. Diversity was highest in the southern and southeastern provinces and declined to north and west. Only the two invasive species were found in the northern part of the country where they occur primarily in protected cropping. By 2009, indigenous species were mainly found in remote mountainous areas and were mostly absent from extensive agricultural areas. CONCLUSIONS/SIGNIFICANCE: Invasions by some members of the whitefly B. tabaci species complex can be rapid and widespread, and indigenous species closely related to the invaders are replaced.

  8. Do invasive alien plants really threaten river bank vegetation? A case study based on plant communities typical for Chenopodium ficifolium-An indicator of large river valleys.

    Science.gov (United States)

    Nobis, Agnieszka; Nowak, Arkadiusz; Rola, Kaja

    2018-01-01

    Riparian zones are very rich in species but subjected to strong anthropogenic changes and extremely prone to alien plant invasions, which are considered to be a serious threat to biodiversity. Our aim was to determine the spatial distribution of Chenopodium ficifolium, a species demonstrating strong confinement to large river valleys in Central Europe and an indicator of annual pioneer nitrophilous vegetation developing on river banks, which are considered to be of importance to the European Community. Additionally, the habitat preferences of the species were analysed. Differences in the richness and abundance of species diagnostic for riverside habitats, as well as the contribution of resident and invasive alien species in vegetation plots along three rivers differing in terms of size and anthropogenic impact were also examined. Finally, the effect of invaders on the phytocoenoses typical for C. ficifolium was assessed. The frequency of C. ficifolium clearly decreased with an increasing distance from the river. Among natural habitats, the species mostly preferred the banks of large rivers. The vegetation plots developing on the banks of the three studied rivers differed in total species richness, the number and cover of resident, diagnostic and invasive alien species, as well as in species composition. Our research indicates that abiotic and anthropogenic factors are the most significant drivers of species richness and plant cover of riverbank vegetation, and invasive alien plants affect this type of vegetation to a small extent.

  9. Clearing invasive alien plants as a cost-effective strategy for water catchment management: The case of the Olifants river catchment, South Africa

    Directory of Open Access Journals (Sweden)

    Tshepo Morokong

    2016-12-01

    Full Text Available Invasive alien plants have a negative impact on ecosystem goods and services derived from ecosystems. Consequently, the aggressive spread of invasive alien plants (IAPs in the river catchments of South Africa is a major threat to, inter alia, water security. The Olifants River catchment is one such a catchment that is under pressure because of the high demand for water from mainly industrial sources and unsustainable land-use, which includes IAPs. This study considered the cost-effectiveness of clearing IAPs and compared these with the cost of a recently constructed dam. The methods used for data collection were semistructured interviews, site observation, desktop data analysis, and a literature review to assess the impact of IAPs on the catchment’s water supply. The outcomes of this study indicate that clearing invasive alien plants is a cost-effective intervention with a Unit Reference Value (URV of R1.44/m3, which compares very favourably with that of the De Hoop dam, the URV for which is R2.93/m3. These results suggest that clearing invasive alien plants is a cost-effective way of catchment management, as the opportunity cost of not doing so (forfeiting water to the value of R2.93/m3 is higher than that of protecting the investment in the dam.

  10. The prioritisation of invasive alien plant control projects using a multi-criteria decision model informed by stakeholder input and spatial data

    CSIR Research Space (South Africa)

    Forsyth, GG

    2012-07-01

    Full Text Available operations in the Western Cape, South Africa. Stakeholder workshops were held to identify a goal and criteria and to conduct pair-wise comparisons to weight the criteria with respect to invasive alien plant control. The combination of stakeholder input (to...

  11. Preventing a new invasive alien plant from entering and spreading in the Euro-Mediterranean region: The case study of Parthenium hysterophorus

    NARCIS (Netherlands)

    Brunel, S.; Panetta, D.; Fried, G.; Kriticos, D.; Prasad, R.; Oude Lansink, A.G.J.M.; Shabbir, A.; Yaacoby, T.

    2014-01-01

    Parthenium or famine weed (Parthenium hysterophorus L.) is an annual plant originating from the Americas, which is a major invasive alien plant in almost all continents. While the deleterious impacts of the species on agriculture, human and animal health have been well documented, information on the

  12. Who's in charge here anyway? Polycentric governance configurations and the development of policy on invasive alien species in the semisovereign Caribbean

    NARCIS (Netherlands)

    Vaas, J.|info:eu-repo/dai/nl/412502976; Driessen, P.P.J.|info:eu-repo/dai/nl/069081417; Giezen, Mendel; van Laerhoven, F.S.J.|info:eu-repo/dai/nl/314406832; Wassen, M.J.|info:eu-repo/dai/nl/07165710X

    2017-01-01

    We address the development of policy by polycentric governance configurations, taking Caribbean overseas territories and their advancements on invasive alien species (IAS) policy as an example. The British, Dutch, and French islands in the Caribbean address this matter to different degrees, which we

  13. Torrefaction of invasive alien plants: Influence of heating rate and other conversion parameters on mass yield and higher heating value.

    Science.gov (United States)

    Mundike, Jhonnah; Collard, François-Xavier; Görgens, Johann F

    2016-06-01

    With the aim of controlling their proliferation, two invasive alien plants, Lantana camara (LC) and Mimosa pigra (MP), both widespread in Africa, were considered for torrefaction for renewable energy applications. Using thermogravimetric analysis, the influence of heating rate (HR: 2.18-19.82°Cmin(-1)) together with variable temperature and hold time on char yield and HHV (in a bomb calorimeter) were determined. Statistically significant effects of HR on HHV with optima at 10.5°Cmin(-1) for LC and 20°Cmin(-1) for MP were obtained. Increases of HHV up to 0.8MJkg(-1) or energy yield greater than 10%, together with a 3-fold reduction in torrefaction conversion time could be achieved by optimisation of HR. Analysis of the torrefaction volatiles by TG-MS showed that not only hemicelluloses, but also lignin conversion, could influence the optimum HR value. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Differences found in the macroinvertebrate community composition in the presence or absence of the invasive alien crayfish, Orconectes hylas

    Science.gov (United States)

    Freeland-Riggert, Brandye T.; Cairns, Stefan H.; Poulton, Barry C.; Riggert, Chris M.

    2016-01-01

    Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon)) has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae), and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae). Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities.

  15. Understanding the dynamics in distribution of invasive alien plant species under predicted climate change in Western Himalaya.

    Science.gov (United States)

    Thapa, Sunil; Chitale, Vishwas; Rijal, Srijana Joshi; Bisht, Neha; Shrestha, Bharat Babu

    2018-01-01

    Invasive alien plant species (IAPS) can pose severe threats to biodiversity and stability of native ecosystems, therefore, predicting the distribution of the IAPS plays a crucial role in effective planning and management of ecosystems. In the present study, we use Maximum Entropy (MaxEnt) modelling approach to predict the potential of distribution of eleven IAPS under future climatic conditions under RCP 2.6 and RCP 8.5 in part of Kailash sacred landscape region in Western Himalaya. Based on the model predictions, distribution of most of these invasive plants is expected to expand under future climatic scenarios, which might pose a serious threat to the native ecosystems through competition for resources in the study area. Native scrublands and subtropical needle-leaved forests will be the most affected ecosystems by the expansion of these IAPS. The present study is first of its kind in the Kailash Sacred Landscape in the field of invasive plants and the predictions of potential distribution under future climatic conditions from our study could help decision makers in planning and managing these forest ecosystems effectively.

  16. Differences Found in the Macroinvertebrate Community Composition in the Presence or Absence of the Invasive Alien Crayfish, Orconectes hylas.

    Science.gov (United States)

    Freeland-Riggert, Brandye T; Cairns, Stefan H; Poulton, Barry C; Riggert, Christopher M

    2016-01-01

    Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon)) has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae), and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae). Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities.

  17. Differences Found in the Macroinvertebrate Community Composition in the Presence or Absence of the Invasive Alien Crayfish, Orconectes hylas.

    Directory of Open Access Journals (Sweden)

    Brandye T Freeland-Riggert

    Full Text Available Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae, and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae. Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities.

  18. Does Mutualism Drive the Invasion of Two Alien Species? The Case of Solenopsis invicta and Phenacoccus solenopsis

    Science.gov (United States)

    Zhou, Aiming; Lu, Yongyue; Zeng, Ling; Xu, Yijuan; Liang, Guangwen

    2012-01-01

    Although mutualism between ants and honeydew-producing hemipterans has been extensively recognized in ecosystem biology, however few attempts to test the hypothesis that mutualism between two alien species leads to the facilitation of the invasion process. To address this problem, we focus on the conditional mutualism between S. invicta and P. solenopsis by field investigations and indoor experiments. In the laboratory, ant colony growth increased significantly when ants had access to P. solenopsis and animal-based food. Honeydew produced by P. solenopsis also improved the survival of ant workers. In the field, colony density of P. solenopsis was significantly greater on plots with ants than on plots without ants. The number of mealybug mummies on plants without fire ants was almost three times that of plants with fire ants, indicating a strong effect of fire ants on mealybug survival. In addition, the presence of S. invicta successfully contributed to the spread of P. solenopsis. The quantity of honeydew consumption by S. invicta was significantly greater than that of a presumptive native ant, Tapinoma melanocephalum. When compared with the case without ant tending, mealybugs tended by ants matured earlier and their lifespan and reproduction increased. T. melanocephalum workers arrived at honeydew more quickly than S. invicta workers, while the number of foraging S. invicta workers on plants steadily increased, eventually exceeding that number of T. melanocephalum foragers. Overall, these results suggest that the conditional mutualism between S. invicta and P. solenopsis facilitates population growth and fitness of both species. S. invicta tends to acquire much more honeydew and drive away native ants, promoting their predominance. These results suggest that the higher foraging tempo of S. invicta may provide more effective protection of P. solenopsis than native ants. Thus mutualism between these two alien species may facilitate the invasion success of both

  19. Introduced pathogens follow the invasion front of a spreading alien host

    Science.gov (United States)

    Ann E. Hajek; Patrick C. Tobin

    2011-01-01

    When an invasive species first colonizes an area, there is an interval before any host-specific natural enemies arrive at the new location. Population densities of newly invading species are low, and the spatial and temporal interactions between spreading invasive species and specific natural enemies that follow are poorly understood. We measured infection rates of two...

  20. Fire and simulated herbivory have antagonistic effects on resistance of savanna grasslands to alien shrub invasion

    NARCIS (Netherlands)

    te Beest, Mariska; Mpandza, Nokukhanya J.; Olff, Han

    Question Resistance of the native community has been identified as an important factor limiting invasion success and invader impact. However, to what extent resistance interacts with disturbance to control invasion success remains unclear. We studied the interaction between biotic resistance, fire

  1. Quantifying the Establishment Likelihood of Invasive Alien Species Introductions Through Ports with Application to Honeybees in Australia.

    Science.gov (United States)

    Heersink, Daniel K; Caley, Peter; Paini, Dean R; Barry, Simon C

    2016-05-01

    The cost of an uncontrolled incursion of invasive alien species (IAS) arising from undetected entry through ports can be substantial, and knowledge of port-specific risks is needed to help allocate limited surveillance resources. Quantifying the establishment likelihood of such an incursion requires quantifying the ability of a species to enter, establish, and spread. Estimation of the approach rate of IAS into ports provides a measure of likelihood of entry. Data on the approach rate of IAS are typically sparse, and the combinations of risk factors relating to country of origin and port of arrival diverse. This presents challenges to making formal statistical inference on establishment likelihood. Here we demonstrate how these challenges can be overcome with judicious use of mixed-effects models when estimating the incursion likelihood into Australia of the European (Apis mellifera) and Asian (A. cerana) honeybees, along with the invasive parasites of biosecurity concern they host (e.g., Varroa destructor). Our results demonstrate how skewed the establishment likelihood is, with one-tenth of the ports accounting for 80% or more of the likelihood for both species. These results have been utilized by biosecurity agencies in the allocation of resources to the surveillance of maritime ports. © 2015 Society for Risk Analysis.

  2. Citizen Science and Open Data: a Model for Invasive Alien Plant Species in Kenya's Northern Rangelands

    Science.gov (United States)

    Amirazodi, S.; Griffin, R.; Flores Cordova, A. I.; Ouko, E.; Omondi, S.; Mugo, R. M.; Farah, H.; Flores Cordova, A. I.; Adams, E. C.

    2017-12-01

    Invasive species in African savannas pose great threat to the native biodiversity and changes ecosystem functioning. In the forest sector, for instance Acacia species are important sources of fuel-wood, yet at the same time they have increased strain on water resources and shrunken forage spaces for both livestock and wildlife. In recently infested regions, invasive species can progress through the stages of introduction, establishment and dispersal to a full range. Currently there is much worldwide interest in predicting distributions of invasive species, and several organizations are faced with questions of whether and how to tackle such environmental challenges, or how to interpret predictions from the science community. Conservation practioners require mapped estimates of where species could persist in a given region, and this is associated to information about the biotope - i.e. the geographic location of the species' niche. The process of collecting species distribution data for identifying the potential distribution of the invasive species in the invaded ranges has become a challenge both in terms of resource and time allocation. This study highlights innovative approaches in crowdsourcing validation data in mapping and modelling invasive species (Acacia reficiens and Cactus) through involvement of the local communities. The general approach was to model the distribution of A. reficiens and Cactus (Opuntia Spp) using occurrence records from native range, then project the model into new regions to assess susceptibility to invasion using climatic and topographic environmental variables. The models performed better than random prediction (P 0.75.

  3. Evaluating the capability of Landsat 8 OLI and SPOT 6 for discriminating invasive alien species in the African Savanna landscape

    Science.gov (United States)

    Kganyago, Mahlatse; Odindi, John; Adjorlolo, Clement; Mhangara, Paidamoyo

    2018-05-01

    Globally, there is paucity of accurate information on the spatial distribution and patch sizes of Invasive Alien Plants (IAPs) species. Such information is needed to aid optimisation of control mechanisms to prevent further spread of IAPs and minimize their impacts. Recent studies have shown the capability of very high spatial (<1 m) and spectral resolution (<10 nm) data for discriminating vegetation species. However, very high spatial resolution may introduce significant intra-species spectral variability and result in reduced mapping accuracy, while higher spectral resolution data are commonly limited to smaller areas, are costly and computationally expensive. Alternatively, medium and high spatial resolution data are available at low or no cost and have limitedly been evaluated for their potential in determining invasion patterns relevant for invasion ecology and aiding effective IAPs management. In this study medium and high resolution datasets from Landsat Operational Land Imager (OLI) and SPOT 6 sensors respectively, were evaluated for mapping the distribution and patch sizes of IAP, Parthenium hysterophorus in the savannah landscapes of KwaZulu-Natal, South Africa. Support Vector Machines (SVM) classifier was used for classification of both datasets. Results indicated that SPOT 6 had a higher overall accuracy (86%) than OLI (83%) in mapping P. hysterophorus. The study found larger distributions and patch sizes in OLI than in SPOT 6 as a result of possible P. hysterophorus expansion due to temporal differences between images and coarser pixels were insufficient to delineate gaps inside larger patches. On the other hand, SPOT 6 showed better capabilities of delineating gaps and boundaries of patches, hence had better estimates of distribution and patch sizes. Overall, the study showed that OLI may be suitable for mapping well-established patches for the purpose of large scale monitoring, while SPOT 6 can be used for mapping small patches and prioritising them

  4. Do alien species matter? Impacts of invasions in Indian freshwater systems and challenges in management

    Directory of Open Access Journals (Sweden)

    Murugan Muralidharan

    2017-06-01

    Full Text Available Alongside anthropogenic activities and habitat destruction, invasions are regarded as one of the most influential components of global change. India as a growing economy and rapidly developing nation has been constantly engaged in infrastructure development which consequently has led to depletion of natural resources and declining quality of habitats aquatic systems in particular. Invasions that have established from the introductions in past during the colonial era and recently spread species are great challenges that hamper survival of aquatic resources. As of 2015, 20 plants, one mollusc and 37 fishes are known to have naturalized in Indian water bodies. Awareness on the invasive species along with detailed information on the ecosystem-wide impacts is essential for management.

  5. Selective logging and fire as drivers of alien grass invasion in a Bolivian tropical dry forest

    NARCIS (Netherlands)

    Veldman, J.W.; Mostacedo, B.; Peña-Claros, M.; Putz, F.E.

    2009-01-01

    Logging is an integral component of most conceptual models that relate human land-use and climate change to tropical deforestation via positive-feedbacks involving fire. Given that grass invasions can substantially alter fire regimes, we studied grass distributions in a tropical dry forest 1-5 yr

  6. Alien plant invasions in tropical and sub-tropical savannas: patterns, processes and prospects

    Czech Academy of Sciences Publication Activity Database

    Foxcroft, L. C.; Richardson, D. M.; Rejmánek, M.; Pyšek, Petr

    2010-01-01

    Roč. 12, č. 12 (2010), s. 3913-3933 ISSN 1387-3547 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60050516 Keywords : savannas * plant invasions * world Subject RIV: EF - Botanics Impact factor: 3.474, year: 2010

  7. Flowering phenology and reproductive effort of the invasive alien plant Heracleum mantegazzianum

    Czech Academy of Sciences Publication Activity Database

    Perglová, Irena; Pergl, Jan; Pyšek, Petr

    2006-01-01

    Roč. 78, - (2006), s. 265-285 ISSN 0032-7786 R&D Projects: GA ČR GA206/05/0323; GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60050516 Keywords : invasions * phenology * fecundity Subject RIV: EF - Botanics Impact factor: 2.119, year: 2006

  8. Impact of invasions by alien plants on soil seed bank communities: emerging patterns

    Czech Academy of Sciences Publication Activity Database

    Gioria, Margherita; Jarošík, Vojtěch; Pyšek, Petr

    2014-01-01

    Roč. 16, č. 3 (2014), s. 132-142 ISSN 1433-8319 R&D Projects: GA ČR(CZ) GAP504/11/1028; GA ČR GB14-36079G Institutional support: RVO:67985939 Keywords : plant invasions * impact * soil seed bank Subject RIV: EF - Botanics Impact factor: 3.606, year: 2014

  9. How the Yellowhammer became a Kiwi: the history of an alien bird invasion revealed

    Czech Academy of Sciences Publication Activity Database

    Pipek, P.; Pyšek, Petr; Blackburn, T. M.

    2015-01-01

    Roč. 24, č. 1 (2015), s. 1-31 ISSN 1619-0033 Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : bird invasions * historical records * New Zealand Subject RIV: EH - Ecology, Behaviour

  10. European map of alien plant invasions, based on the quantitative assessment across habitats

    Czech Academy of Sciences Publication Activity Database

    Chytrý, M.; Pyšek, Petr; Wild, Jan; Pino, J.; Maskell, L. C.; Vila, M.

    2009-01-01

    Roč. 15, č. 1 (2009), s. 98-107 ISSN 1366-9516 R&D Projects: GA MŠk LC06073 Grant - others:Evropská komise(XE) GOCE-CT-2003-506675 Institutional research plan: CEZ:AV0Z60050516 Keywords : plant invasions * habitat * Europe Subject RIV: EF - Botanics Impact factor: 4.224, year: 2009

  11. Habitat invasions by alien plants: a quantitative comparison between Mediterranean, subcontinental and oceanic regions of Europe

    Czech Academy of Sciences Publication Activity Database

    Chytrý, M.; Maskell, L. C.; Pino, J.; Pyšek, Petr; Vila, M.; Font, X.; Smart, S. M.

    2008-01-01

    Roč. 45, č. 2 (2008), s. 448-458 ISSN 0021-8901 R&D Projects: GA MŠk(CZ) LC06073 Grant - others:ALARM(XE) GOCE-CT-2003-506675 Institutional research plan: CEZ:AV0Z60050516 Keywords : invasibility * neophyte * habitat Subject RIV: EF - Botanics Impact factor: 4.560, year: 2008

  12. Assessing patterns in introduction pathways of alien species by linking major invasion data bases

    Czech Academy of Sciences Publication Activity Database

    Saul, W.-C.; Roy, H. E.; Booy, O.; Carnevali, L.; Chen, H.-J.; Genovesi, P.; Harrower, C.; Hulme, P. E.; Pagad, S.; Pergl, Jan; Jeschke, J.M.

    2017-01-01

    Roč. 54, č. 2 (2017), s. 657-669 ISSN 0021-8901 R&D Projects: GA ČR(CZ) GAP504/11/1028 Grant - others:COST(XE) TD1209 Program:FA Institutional support: RVO:67985939 Keywords : invasions * pathways * databases Subject RIV: EH - Ecology, Behaviour OBOR OECD: Biodiversity conservation Impact factor: 5.301, year: 2016

  13. Seven Recommendations to Make Your Invasive Alien Species Data More Useful

    Czech Academy of Sciences Publication Activity Database

    Groom, Q. J.; Adriaens, T.; Desmet, P.; Simpson, A.; De Wever, A.; Bazos, I.; Cardoso, A.-C.; Charles, L.; Christopoulou, A.; Gazda, A.; Helmisaari, H.-S.; Hobern, D.; Josefsson, M.; Lucy, F.; Marisavljevic, D.; Oszako, T.; Pergl, Jan; Petrovic-Obradovic, O.; Prévot, C.; Ravn, H. P.; Richards, G.; Roques, A.; Roy, H. E.; Rozenberg, M.-A. A.; Scalera, R.; Tricarico, E.; Trichkova, T.; Vercayie, D.; Zenetos, A.; Vanderhoeven, S.

    2017-01-01

    Roč. 3, JUNE (2017), s. 1-8, č. článku 13. ISSN 2297-4687 Grant - others:COST(XE) TD1209 Program:FA Institutional support: RVO:67985939 Keywords : data management * invasions * databses Subject RIV: EH - Ecology, Behaviour OBOR OECD: Biodiversity conservation

  14. Blurring alien introduction pathways risks losing focus on invasive species policy

    Czech Academy of Sciences Publication Activity Database

    Hulme, P. E.; Bacher, S.; Kenis, M.; Kühn, I.; Pergl, Jan; Pyšek, Petr; Roques, A.; Vila, M.

    2017-01-01

    Roč. 10, č. 2 (2017), s. 265-266 ISSN 1755-263X Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : biological invasions * introduction s pathways * management Subject RIV: EH - Ecology, Behaviour OBOR OECD: Biodiversity conservation Impact factor: 7.020, year: 2016

  15. EMAPi 2015: Highlighting links between science and management of alien plant invasions

    Czech Academy of Sciences Publication Activity Database

    Daehler, C. C.; van Kleunen, M.; Pyšek, Petr; Richardson, D. M.

    2016-01-01

    Roč. 30, č. 1 (2016), s. 1-3 ISSN 1619-0033 Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : invasions * plants * animals Subject RIV: EH - Ecology, Behaviour

  16. Planting intensity, residence time, and species traits determine invasion success of alien woody species

    Czech Academy of Sciences Publication Activity Database

    Pyšek, Petr; Křivánek, Martin; Jarošík, Vojtěch

    2009-01-01

    Roč. 90, č. 10 (2009), s. 2734-2744 ISSN 0012-9658 R&D Projects: GA ČR GA206/05/0323; GA MŠk LC06073 Grant - others:Evropská komise(XE) GOCE-CT-2003-506675 ALARM Institutional research plan: CEZ:AV0Z60050516 Keywords : woody species * invasion * planting Subject RIV: EF - Botanics Impact factor: 4.411, year: 2009

  17. Maps of the level of invasion of the Czech Republic by alien plants

    Czech Academy of Sciences Publication Activity Database

    Chytrý, M.; Wild, Jan; Pyšek, Petr; Tichý, L.; Danihelka, Jiří; Knollová, I.

    2009-01-01

    Roč. 81, č. 3 (2009), s. 187-207 ISSN 0032-7786 R&D Projects: GA MŠk LC06073 Grant - others:Evropská komise(XE) GOCE-CT-2003-506675 Institutional research plan: CEZ:AV0Z60050516 Keywords : plant invasions * distribution * mapping Subject RIV: EF - Botanics Impact factor: 2.638, year: 2009 http://www.preslia.cz/P093Chytry. pdf

  18. Tackling invasive alien species in Europe II: threats and opportunities until 2020

    Czech Academy of Sciences Publication Activity Database

    Piria, M.; Copp, G. H.; Dick, J. T. A.; Duplić, A.; Groom, Q.; Jelić, D.; Lucy, F. E.; Roy, H. E.; Sarat, E.; Simonović, P.; Tomljanović, T.; Tricarico, E.; Weinlander, M.; Adámek, Zdeněk; Bedolfe, S.; Coughlan, N. E.; Davis, E.; Dobrzycka-Krahel, A.; Grgić, Z.; Kırankaya, S. G.; Ekmekci, F. G.; Lajtner, J.; Lukas, J. A. Y.; Koutsikos, N.; Mennen, G. J.; Mitić, B.; Pastorino, P.; Ruokonen, T. J.; Skóra, M. E.; Smith, E. R. C.; Šprem, N.; Tarkan, A. S.; Treer, T.; Vardakas, L.; Vehanen, T.; Vilizzi, L.; Zanella, D.; Caffrey, J. M.

    2017-01-01

    Roč. 8, č. 3 (2017), s. 273-286 E-ISSN 1989-8649. [Freshwater Invasives – Networking for Strategy (FINS-II). Zagreb, 11.07.2016-14.07.2016] Institutional support: RVO:68081766 Keywords : non-native species * legislation * policy * environmental management * sequential rank voting * scoring system Subject RIV: EH - Ecology, Behaviour OBOR OECD: Biodiversity conservation Impact factor: 1.439, year: 2016

  19. Scoring environmental and socioeconomic impacts of alien plants invasive in Europe

    Czech Academy of Sciences Publication Activity Database

    Rumlerová, Zuzana; Vila, M.; Pergl, Jan; Nentwig, W.; Pyšek, Petr

    2016-01-01

    Roč. 18, č. 12 (2016), s. 3697-3711 ISSN 1387-3547 R&D Projects: GA ČR(CZ) GAP504/11/1028; GA ČR GB14-36079G Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : invasion impacts * scoring * Europe Subject RIV: EH - Ecology, Behaviour Impact factor: 2.473, year: 2016

  20. Effects of an alien ant invasion on abundance, behavior, and reproductive success of endemic island birds.

    Science.gov (United States)

    Davis, Naomi E; O'Dowd, Dennis J; Green, Peter T; Nally, Ralph Mac

    2008-10-01

    Biological invaders can reconfigure ecological networks in communities, which changes community structure, composition, and ecosystem function. We investigated whether impacts caused by the introduced yellow crazy ant (Anoplolepis gracilipes), a pantropical invader rapidly expanding its range, extend to higher-order consumers by comparing counts, behaviors, and nesting success of endemic forest birds in ant-invaded and uninvaded rainforest on Christmas Island (Indian Ocean). Point counts and direct behavioral observations showed that ant invasion altered abundances and behaviors of the bird species we examined: the Island Thrush (Turdus poliocephalus erythropleurus), Emerald Dove (Chalcophaps indica natalis), and Christmas Island White-eye (Zosterops natalis). The thrush, which frequents the forest floor, altered its foraging and reproductive behaviors in ant-invaded forest, where nest-site location changed, and nest success and juvenile counts were lower. Counts of the dove, which forages exclusively on the forest floor, were 9-14 times lower in ant-invaded forest. In contrast, counts and foraging success of the white-eye, a generalist feeder in the understory and canopy, were higher in ant-invaded forest, where mutualism between the ant and honeydew-secreting scale insects increased the abundance of scale-insect prey. These complex outcomes involved the interplay of direct interference by ants and altered resource availability and habitat structure caused indirectly by ant invasion. Ecological meltdown, rapidly unleashed by ant invasion, extended to these endemic forest birds and may affect key ecosystem processes, including seed dispersal.

  1. Drought-associated absence of alien invasive anchorworm, Lernaea cyprinacea (Copepoda: Lernaeidae, is related to changes in fish health

    Directory of Open Access Journals (Sweden)

    Rachel L. Welicky

    2017-12-01

    that host condition and health varies greatly with respect to drought and infection, and provides the necessary data for follow-up studies in post-drought conditions. Keywords: Alien invasive, Cichlidae, Fish parasites, Host condition, Tilapia, 18S ribosomal DNA

  2. Mapping invasive alien Acacia dealbata Link using ASTER multispectral imagery: a case study in central-eastern of Portugal

    Energy Technology Data Exchange (ETDEWEB)

    Martins, F.; Alegria, C.; Artur, G.

    2016-07-01

    Aim of the study: Acacia dealbata is an alien invasive species that is widely spread in Portugal. The main goal of this study was to produce an accurate and detailed map for this invasive species using ASTER multispectral imagery. Area of study: The central-eastern zone of Portugal was used as study area. This whole area is represented in an ASTER scene covering about 321.1 x 103 ha. Material and methods: ASTER imagery of two dates (flowering season and dry season) were classified by applying three supervised classifiers (Maximum Likelihood, Support Vector Machine and Artificial Neural Networks) to five different land cover classifications (from most generic to most detailed land cover categories). The spectral separability of the land cover categories was analyzed and the accuracy of the 30 produced maps compared. Main results: The highest classification accuracy for acacia mapping was obtained using the flowering season imagery, the Maximum Likelihood classifier and the most detailed land cover classification (overall accuracy of 86%; Kappa statistics of 85%; acacia class Kappa statistics of 100%). As a result, the area occupied by acacia was estimated to be approximated 24,770 ha (i.e. 8% of the study area). Research highlights: The methodology explored proved to be a cost-effective solution for acacia mapping in central-eastern of Portugal. The obtained map enables a more accurate and detailed identification of this species’ invaded areas due to its spatial resolution (minimum mapping unit of 0.02 ha) providing a substantial improvement comparably to the existent national land cover maps to support monitoring and control activities. (Author)

  3. The role of habitat factors in successful invasion of alien plant Acer negundo in riparian zones.

    Science.gov (United States)

    Sikorski, Piotr; Sikorska, Daria

    2016-04-01

    Ash-leaved maple (Acer negundo) is one of the most invasive species occurring in riparian zones. The invasion is especially effective in disturbed areas, as the plant favours anthropogenic sites. The plant was also observed to be able to penetrate into sandy bars, also those separated from the land, inaccessible to people. It's removal is time-consuming and laborious, often involves damage done to sensitive vegetation and the results are doubtful, as the plant quickly regenerates. The invasion patterns and establishment of ash-leaved maple in natural ecosystems are poorly investigated. The aim of this study was to test how habitat factors such as: light availability, soil characteristics and competition contribute to ash-leaved maple effective colonization of natural sand bars free from anthropogenic pressure. In 2014 sand bars located in Vistula River Valley in Warsaw were inventoried and classified basing on their development stage as 1 - initial, 2 - unstable, 3 - stable. Apart from the occurrence of the invasive ash-leaved maple the plants competing with it were recognized and the percentage of the shoots of shrubs and herbaceous plants was estimated. PAR was measured at ground level and 1 meter above ground, the thickness of organic layer formed on the top of the sand was also measured as the indicator of sand bar development stage. The maple's survival in extremely difficult conditions resembles the strategy of willows and poplars naturally occurring in the riparian zones, which are well adapted to this environment. The success of invasion strongly depends on the plants establishment during sand bars initial stage of development. The seedlings growth correlates with the age of the sand bar (r1=0,41, r2=0,42 i r3=0,57). The colonization lasts for 4-6 years and the individuals start to cluster in bigger parches. After that period the maple turns into the phase of competition for space. Habitat factors such as shading (r2=0,41 i r3=0,51) and organic layer

  4. Predators vs. alien: differential biotic resistance to an invasive species by two resident predators

    Directory of Open Access Journals (Sweden)

    Calum MacNeil

    2013-10-01

    Full Text Available The success of invading species can be restricted by interspecific interactions such as competition and predation (i.e. biotic resistance from resident species, which may be natives or previous invaders. Whilst there are myriad examples of resident species preying on invaders, simply showing that such an interaction exists does not demonstrate that predation limits invader establishment, abundance or spread. Support for this conclusion requires evidence of negative associations between invaders and resident predators in the field and, further, that the predator-prey interaction is likely to strongly regulate or potentially de-stabilise the introduced prey population. Moreover, it must be considered that different resident predator species may have different abilities to restrict invaders. In this study, we show from analysis of field data that two European predatory freshwater amphipods, Gammarus pulex and G. duebeni celticus, have strong negative field associations with their prey, the invasive North American amphipod Crangonyx pseudogracilis. This negative field association is significantly stronger with G. pulex, a previous and now resident invader in the study sites, than with the native G. d. celticus. These field patterns were consistent with our experimental findings that both resident predators display potentially population de-stabilising Type II functional responses towards the invasive prey, with a significantly greater magnitude of response exhibited by G. pulex than by G. d. celticus. Further, these Type II functional responses were consistent across homo- and heterogeneous environments, contrary to the expectation that heterogeneity facilitates more stabilising Type III functional responses through the provision of prey refugia. Our experimental approach confirms correlative field surveys and thus supports the hypothesis that resident predatory invertebrates are differentially limiting the distribution and abundance of an

  5. Evaluating the "recovery level" of endangered species without prior information before alien invasion.

    Science.gov (United States)

    Watari, Yuya; Nishijima, Shota; Fukasawa, Marina; Yamada, Fumio; Abe, Shintaro; Miyashita, Tadashi

    2013-11-01

    For maintaining social and financial support for eradication programs of invasive species, quantitative assessment of recovery of native species or ecosystems is important because it provides a measurable parameter of success. However, setting a concrete goal for recovery is often difficult owing to lack of information prior to the introduction of invaders. Here, we present a novel approach to evaluate the achievement level of invasive predator management based on the carrying capacity of endangered species estimated using long-term monitoring data. In Amami-Oshima Island, Japan, where the eradication project of introduced small Indian mongoose is ongoing since 2000, we surveyed the population densities of four endangered species threatened by the mongoose (Amami rabbit, the Otton frog, Amami tip-nosed frog, and Amami Ishikawa's frog) at four time points ranging from 2003 to 2011. We estimated the carrying capacities of these species using the logistic growth model combined with the effects of mongoose predation and environmental heterogeneity. All species showed clear tendencies toward increasing their density in line with decreased mongoose density, and they exhibited density-dependent population growth. The estimated carrying capacities of three endangered species had small confidence intervals enough to measure recovery levels by the mongoose management. The population density of each endangered species has recovered to the level of the carrying capacity at about 20-40% of all sites, whereas no individuals were observed at more than 25% of all sites. We propose that the present approach involving appropriate monitoring data of native organism populations will be widely applicable to various eradication projects and provide unambiguous goals for management of invasive species.

  6. The invasion of five alien species in the Delta do Parnaíba Environmental Protection Area, Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Daniel Loebmann

    2010-09-01

    Full Text Available Marine biological invasions have been regarded as one of the major causes of native biodiversity loss, with shipping and aquaculture being the leading contributors for the introductions of alien species in aquatic ecosystems. In the present study, five aquatic alien species (one mollusk, three crustaceans and one fish species were detected during dives, shore searches and from the fisheries on the coast of the Delta do Parnaíba Environmental Protection Area, in the States of Piauí and Maranhão, Northeastern Brazil. The species were the bicolor purse-oyster Isognomon bicolor, the whiteleg shrimp Litopenaeus vannamei, the giant river prawn Macrobrachium rosenbergii, the Indo-Pacific swimming crab Charybdis hellerii and, the muzzled blenny Omobranchus punctatus. Ballast water (I. bicolor, C. hellerii, and O. punctatus and aquaculture activities (L. vannamei and M. rosenbergii in adjacent areas are the most likely vectors of introduction. All exotic species found have potential impact risks to the environment because they are able to compete against native species for resources (food and habitat. Isognomon bicolor share the same habitat and food items with the native bivalve species of mussels and barnacles. Litopenaeus vannamei share the same habitat and food items with the native penaeids such as the pinkspot shrimp Farfantepenaeus brasiliensis, the Southern brown shrimp Farfantepenaeus subtilis, and the Southern white shrimp Litopenaeus schmitti, and in the past few years L. vannamei was responsible for a viral epidemics in the cultivation tanks that could be transmitted to native penaeid shrimps. Charybdis hellerii is also able to cause impacts on the local fisheries as the species can decrease the populations of native portunid crabs which are commercialized in the studied region. Macrobrachium rosenbergii may be sharing natural resources with the Amazon River prawn Macrobrachium amazonicum. Omobranchus punctatus shares habit with the native

  7. The invasion of five alien species in the Delta do Parnaíba Environmental Protection Area, Northeastern Brazil.

    Science.gov (United States)

    Loebmann, Daniel; Mai, Ana Cecília G; Lee, James T

    2010-09-01

    Marine biological invasions have been regarded as one of the major causes of native biodiversity loss, with shipping and aquaculture being the leading contributors for the introductions of alien species in aquatic ecosystems. In the present study, five aquatic alien species (one mollusk, three crustaceans and one fish species) were detected during dives, shore searches and from the fisheries on the coast of the Delta do Parnaíba Environmental Protection Area, in the States of Piauí and Maranhão, Northeastern Brazil. The species were the bicolor purse-oyster Isognomon bicolor, the whiteleg shrimp Litopenaeus vannamei, the giant river prawn Macrobrachium rosenbergii, the Indo-Pacific swimming crab Charybdis hellerii and, the muzzled blenny Omobranchus punctatus. Ballast water (I. bicolor, C. hellerii, and O. punctatus) and aquaculture activities (L. vannamei and M. rosenbergii) in adjacent areas are the most likely vectors of introduction. All exotic species found have potential impact risks to the environment because they are able to compete against native species for resources (food and habitat). Isognomon bicolor share the same habitat and food items with the native bivalve species of mussels and barnacles. Litopenaeus vannamei share the same habitat and food items with the native penaeids such as the pinkspot shrimp Farfantepenaeus brasiliensis, the Southern brown shrimp Farfantepenaeus subtilis, and the Southern white shrimp Litopenaeus schmitti, and in the past few years L. vannamei was responsible for a viral epidemics in the cultivation tanks that could be transmitted to native penaeid shrimps. Charybdis hellerii is also able to cause impacts on the local fisheries as the species can decrease the populations of native portunid crabs which are commercialized in the studied region. Macrobrachium rosenbergii may be sharing natural resources with the Amazon River prawn Macrobrachium amazonicum. Omobranchus punctatus shares habit with the native redlip blenny

  8. Will climate change drive alien invasive plants into areas of high protection value? An improved model-based regional assessment to prioritise the management of invasions.

    Science.gov (United States)

    Vicente, J R; Fernandes, R F; Randin, C F; Broennimann, O; Gonçalves, J; Marcos, B; Pôças, I; Alves, P; Guisan, A; Honrado, J P

    2013-12-15

    Species distribution models (SDMs) studies suggest that, without control measures, the distribution of many alien invasive plant species (AIS) will increase under climate and land-use changes. Due to limited resources and large areas colonised by invaders, management and monitoring resources must be prioritised. Choices depend on the conservation value of the invaded areas and can be guided by SDM predictions. Here, we use a hierarchical SDM framework, complemented by connectivity analysis of AIS distributions, to evaluate current and future conflicts between AIS and high conservation value areas. We illustrate the framework with three Australian wattle (Acacia) species and patterns of conservation value in Northern Portugal. Results show that protected areas will likely suffer higher pressure from all three Acacia species under future climatic conditions. Due to this higher predicted conflict in protected areas, management might be prioritised for Acacia dealbata and Acacia melanoxylon. Connectivity of AIS suitable areas inside protected areas is currently lower than across the full study area, but this would change under future environmental conditions. Coupled SDM and connectivity analysis can support resource prioritisation for anticipation and monitoring of AIS impacts. However, further tests of this framework over a wide range of regions and organisms are still required before wide application. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Individual and temporal variation in habitat association of an alien carnivore at its invasion front.

    Directory of Open Access Journals (Sweden)

    Claudia Melis

    Full Text Available Gathering information on how invasive species utilize the habitat is important, in order to better aim actions to reduce their negative impact. We studied habitat use and selection of 55 GPS-marked raccoon dogs (30 males, 25 females at their invasion front in Northern Sweden, with particular focus on differences between males and females, between movement states, and between seasons and times of the day. Daily movement pattern was used to classify GPS-locations into dispersing and settled. We focused on both anthropogenic and natural landscape characteristics. Since we did not have any a priori knowledge about the spatial scale of raccoon dog habitat selection, we first assessed how landscape characteristics of random points changed with distance from the GPS-location they were paired to. Because changes in habitat use became less pronounced at approximately 5 km for all variables, we focused on habitat use at two spatial scales: fine (500 m and coarse (5 km. Habitat selection was strongest at the coarse scale, and reflected the results found for habitat use. Raccoon dogs selected agricultural areas and wetlands, lower altitudes, and shallow slopes, and avoided forests, open natural areas, and areas close to water and roads. There were no differences in habitat selection between males and females, or between movement states. This lack of sexual segregation increases the probability of encountering potential mates during dispersal, and therefore the likelihood for reproduction in new areas. The seasonal and diurnal pattern of habitat use may provide guidance for where and when to aim management efforts.

  10. Handling Big Data of Alien Species in Europe: The European Alien Species Information Network Geodatabase

    OpenAIRE

    DERIU IVAN; D'AMICO FABIO; TSIAMIS KONSTANTINOS; GERVASINI EUGENIO; DE JESUS CARDOSO ANA

    2017-01-01

    Building and managing large datasets of alien species is crucial to research, management, and control of biological invasions. To this end, the European Alien Species Information Network (EASIN) platform aggregates, integrates, and harmonizes spatio-temporal data regarding alien species in Europe, including both invasive and non-invasive alien species. These data are stored in the EASIN Geodatabase after their harvesting from relevant sources in the frame of a global and European databases pa...

  11. Living with aliens: effects of invasive shrub honeysuckles on avian nesting.

    Directory of Open Access Journals (Sweden)

    Jason M Gleditsch

    Full Text Available Invasive species have come to the forefront of conservation biology as a major threat to native biodiversity. Habitats dominated by shrub honeysuckles (Lonicera spp. in the United States have been characterized as "ecological traps" by ecologists. Here we tested this hypothesis by investigating the effects of shrub honeysuckles on the nesting ecology of native birds in seven study sites in central Pennsylvania, USA. We examined how the abundance of shrub honeysuckles influenced the selection of nesting substrates and habitat for a community of common songbirds, and the parental-care behavior and nestling development of gray catbirds (Dumetella carolinensis. We found that birds had a strong bias towards nesting in honeysuckle shrubs, but not necessarily for nesting in honeysuckle-dominated habitats. Nest predation rates were affected by the density of nests in a habitat, but not by the overall abundance of honeysuckles in such habitats. Honeysuckle abundance in the habitat did show significant effects on some parental-care behavioral parameters: catbirds had higher nest visitation rates and shorter visit lengths in areas of high honeysuckle density. On average, Gray catbirds fed fruit 12%±0.31 s.e. of their nestling-feeding bouts, mostly fruits of shrub honeysuckles. Nestlings in sites with high honeysuckle density also showed higher mass:tarsus ratios, suggesting a good (possibly better physiological condition of catbird nestlings at the time of fledging. Our study shows that honeysuckle-dominated habitats could have equivocal effects on nesting parameters of common species of native birds. We advise more caution in the widespread denomination of novel plant communities with high densities of honeysuckle as "ecological traps" as effects can be null or positive on native birds in certain localities.

  12. APPROACHES ON THE INVASIVE ALIEN TAXA IN ROMANIA - AMBROSIA ARTEMISIIFOLIA (RAGWEED II

    Directory of Open Access Journals (Sweden)

    Nicoleta IANOVICI

    2011-01-01

    Full Text Available In a previous paper we presented the localities in Romania where we identified populations of Ambrosia artemisiifolia. Between 2008-2011, investigations were continuing. Our data clearly show that Ambrosia is present throughout the country. The territories heavily infested are railway embankments, along traffic routes, gravel pits, building sites, forest edges, industrial areas, cemeteries and recreational areas. It is quite common to find ragweed in many private gardens, or flower pots in urban areas. The few foci observed along riversides got there by household waste and construction waste. In many rural communities find it on the drainage ditches. Disturbed and neglected land (on city limits and outside the city, abandonment of land without subsequent turning of stubble and another wrong agricultural practice, absence of ruderal weed control are the main causes that favor the dissemination of our country. Intensity of anthropogenic influence is manifested mainly by transport of materials and soil movement during road rehabilitation and construction of highways. The recent observations show that could be expected to appear on agricultural fields, now being found only on the outskirts of cultivated land, at 5-6 meters from high traffic roads. Ambrosia benefits from human activities to spread. This implies a strong control strategy. The main objective of the fighting activities need to be to reduce damages caused by its pollen and to limit its expansion. If invasion by Ambrosia is left uncontrolled, increase of allergies could heavily augment the treatments. Knowledge about mechanical or chemical control of ragweed could be very important for road and rail services, agricultural institutions, farmers, staff responsible for managing natural areas, institutions that approves and oversees residential sites and factories, responsible personnel of the administrations from cities and rural localities. Reducing the population is more required than

  13. Preliminary results of studies on the distribution of invasive alien vascular plant species occurring in semi-natural and natural habitats in NW Poland

    Directory of Open Access Journals (Sweden)

    Popiela Agnieszka

    2015-03-01

    Full Text Available In Western Pomerania, as in other areas of Europe, alien species play an increasingly important role. In particular, invasive plants tend to spread rapidly and in large numbers which may reduce diversity of native species, leading to the phenomenon of “trivialisation of flora”, and transform ecosystems. The list of invasive species (32 taxa includes alien species occurring throughout Western Pomerania, and penetrating natural or semi-natural habitats. The second group consists of potentially invasive species (23 taxa, i.e. those distributed across the area under study and tending to increase the number of their localities in semi-natural and natural habitats, taxa invasive only locally, as well as species with missing data, which does not currently allow including them into the first group. Invasive weeds, as well as some epecophytes and archaeophytes occurring only on anthropogenic sites and tending to spread, were not taken into account. Among hemiagriophytes, the most common and troublesome ones are: Conyza canadensis, Erigeron annuus, Lolium multiflorum, Lupinus polyphyllus, Solidago canadensis, S. gigantea. Among holoagriophytes, i.e. the taxa which received the highest naturalisation status, very expansive species, successful in land colonisation, like Acer negundo, Bidens frondosa, B. connata, Clematis vitalba, Elodea canadensis, Epilobium ciliatum, Heracleum sosnowskyi, Impatiens glandulifera, I. parviflora, Padus serotina, Quercus rubra and Robinia pseudoacacia, should be given particular attention. Among the invasive and potentially invasive species, most taxa penetrate plant communities of the Artemisietea and Molinio-Arrhenatheretea class, followed by Querco-Fagetea, Vaccinio-Piceetea, Stellarietea mediae, Salicetea purpurae and Koelerio-Corynophoretea. The number of invasive species is twice as high when compared to the situation of these species in Poland; on the contrary, the number of species inhabiting anthropogenic, semi

  14. The invasion of five alien species in the Delta do Parnaíba Environmental Protection Area, Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Daniel Loebmann

    2010-09-01

    Full Text Available Marine biological invasions have been regarded as one of the major causes of native biodiversity loss, with shipping and aquaculture being the leading contributors for the introductions of alien species in aquatic ecosystems. In the present study, five aquatic alien species (one mollusk, three crustaceans and one fish species were detected during dives, shore searches and from the fisheries on the coast of the Delta do Parnaíba Environmental Protection Area, in the States of Piauí and Maranhão, Northeastern Brazil. The species were the bicolor purse-oyster Isognomon bicolor, the whiteleg shrimp Litopenaeus vannamei, the giant river prawn Macrobrachium rosenbergii, the Indo-Pacific swimming crab Charybdis hellerii and, the muzzled blenny Omobranchus punctatus. Ballast water (I. bicolor, C. hellerii, and O. punctatus and aquaculture activities (L. vannamei and M. rosenbergii in adjacent areas are the most likely vectors of introduction. All exotic species found have potential impact risks to the environment because they are able to compete against native species for resources (food and habitat. Isognomon bicolor share the same habitat and food items with the native bivalve species of mussels and barnacles. Litopenaeus vannamei share the same habitat and food items with the native penaeids such as the pinkspot shrimp Farfantepenaeus brasiliensis, the Southern brown shrimp Farfantepenaeus subtilis, and the Southern white shrimp Litopenaeus schmitti, and in the past few years L. vannamei was responsible for a viral epidemics in the cultivation tanks that could be transmitted to native penaeid shrimps. Charybdis hellerii is also able to cause impacts on the local fisheries as the species can decrease the populations of native portunid crabs which are commercialized in the studied region. Macrobrachium rosenbergii may be sharing natural resources with the Amazon River prawn Macrobrachium amazonicum. Omobranchus punctatus shares habit with the native

  15. Economic assessment of the contribution of biological control to the management of invasive alien plants and to the protection of ecosystem services in South Africa

    CSIR Research Space (South Africa)

    De Lange, Willem J

    2010-07-01

    Full Text Available J-R, Neser S (1999) Past and present intitatives on the biological control of Lantana camara (Verbenaceae) in South Africa. African Entomology Memoir 1: 21-33 Buhlea ER, Margolis M and Ruesink J (2005) Bang for buck: cost-effective control... BW, van der Heyden F, Zimmermann HG, Magadlela D and Willems T (2000) Big returns from small organisms: Developing a strategy for the biological control of invasive alien plants in South Africa. South African Journal of Science 96: 148-152 van Wyk...

  16. Past approaches and future challenges to the management of fire and invasive alien plants in the new Garden Route National Park

    CSIR Research Space (South Africa)

    Kraaij, T

    2011-09-01

    Full Text Available to cite this article: Kraaij T, Cowling RM, Van Wilgen BW. Past approaches and future challenges to the management of fire and invasive alien plants in the new Garden Route National Park. S Afr J Sci. 2011;107(9/10), Art. #633, 11 pages. doi:10... have to set very clear and realistic Page 1 of 11 S Afr J Sci 2011; 107(9/10) http://www.sajs.co.za Review Article objectives to determine the most appropriate management practices for each particular area.24,26 In the fynbos, as elsewhere...

  17. Evidence, perceptions, and trade-offs associated with invasive alien plant control in the Table Mountain National Park, South Africa

    CSIR Research Space (South Africa)

    Van Wilgen, B

    2012-01-01

    Full Text Available , it is regarded as xenophobia or racism (Simberloff 2003), and the proponents of clearing programs have been labeled as ?ecofascists? (Packenham Ecology and Society 17(2): 23 http://www.ecologyandsociety.org/vol17/iss2/art23/ Table 1. Major issues relating... (Jackson et al. 2005). Ethical values Alien species should be protected, especially when they have been present for centuries. The control of alien species is a form of xenophobia or racism (Simberloff 2003), or ethnic cleansing (Todeschini 2000...

  18. Linking biotic homogenization to habitat type, invasiveness and growth form of naturalized alien plants in North America

    Science.gov (United States)

    Hong Qian; Qinfeng. Guo

    2010-01-01

    Aim Biotic homogenization is a growing phenomenon and has recently attracted much attention. Here, we analyse a large dataset of native and alien plants in North America to examine whether biotic homogenization is related to several ecological and biological attributes. Location North America (north of Mexico). Methods We assembled...

  19. Cyperus eragrostis - a new alien species for the Czech flora and the history of its invasion of Europe

    Czech Academy of Sciences Publication Activity Database

    Petřík, Petr

    2003-01-01

    Roč. 75, - (2003), s. 17-28 ISSN 0032-7786 R&D Projects: GA AV ČR KSK6005114; GA AV ČR IAA6005202 Institutional research plan: CEZ:AV0Z6005908 Keywords : Cyperus eragrostis * alien species * casual Subject RIV: EF - Botanics

  20. Nitrate reductase activity (NRA in the invasive alien Fallopia japonica: seasonal variation, differences among habitats types, and comparison with native species

    Directory of Open Access Journals (Sweden)

    Damian Chmura

    2016-09-01

    Full Text Available Nitrate reductase activity (NRA was studied in the invasive alien plant F. japonica (Japanese knotweed during the vegetation season and among natural, semi-natural, and human-made habitats and compared with NRA in selected native species. NRA was measured directly in the field from the beginning of May until the beginning of October. NRA was much higher than in the plant’s native range, i.e., East Asia, and showed a high degree of variation over time with the highest values being reached at the stage of fast vegetative growth and at the beginning of fruiting. NRA was highest on dumping sites probably due to the high nitrogen input into soils and near traffic and the emission of NOx by vehicles. A comparison of the enzyme activity in four selected native plant species indicated that NRA in F. japonica was the highest with the exception of Urtica dioica, which exhibited a similar activity of the enzyme. A detailed comparison with this species showed that differences between these species on particular dates were influenced by differences in the phenology of both plants. The initial results that were obtained suggest that nitrogen pollution in an environment can contribute to habitat invasibility and a high level of NRA, which in addition to the many plant traits that are commonly accepted as characteristic of invasiveness features, may be an important factor that enhances invasion success.

  1. Alien invasive species and biological pollution of the Great Lakes Basin ecosystem[Great Lakes Water Quality Board : Report to the International Joint Commission

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-05-01

    The displacement of important native species in the Great Lakes is a result of an invasion by a succession of non indigenous aquatic species. These invasion also resulted in interference with the proper human water uses and cost billions of dollars. The problem was considered serious enough that the International Joint Commission asked the Great Lakes Water Quality Board in 1999 to review the regulations in place and make recommendations, if necessary, for the implementation of additional measures that could be considered to keep control over the introduction of alien invasive species. Escapes from aquaria, aquaculture, research and educational facilities, canal and diversion water flows, and release of live bait are all sources of this invasion. The effectiveness of alternative technologies to control the invasion was to be examined by the Board. Other efforts taking place to address the situation in the basin are being complemented by the publication of this report. It is considered that the most important source of alien invasive species (AIS) to the Great Lakes is the discharge of ballast water from shipping vessels coming from outside the United States and Canada. A major concern is the role played by vessels reporting no ballast on board (NOBOB) upon entering the basin. A number of recommendations were made concerning: (1) implementation and enforcement of the ballast water discharge standards agreed upon by both countries, (2) the evaluation of the effectiveness of alternative technologies to achieve ballast water discharge standards over the long term, combined with the use of chemical treatment while the evaluation is being performed, (3) the implementation of optimal management practices to control sediments in shipping vessels, (4) modifications to the design of shipping vessels, and (5) the monitoring and contingency plans in the event of a repeat scenario in the future. Composed of an equal number representatives from the United States and Canada, at

  2. Naturalized alien flora of the world: species diversity, taxonomic and phylogenetic patterns, geographic distribution and global hotspots of plant invasion

    Czech Academy of Sciences Publication Activity Database

    Pyšek, Petr; Pergl, Jan; Essl, F.; Lenzer, B.; Dawson, W.; Kreft, H.; Weigelt, P.; Winter, M.; Kartesz, J.; Nishino, M.; Antonova, L. A.; Barcelona, J. F.; Cabezas, F. J.; Cárdenas, D.; Cárdenas-Toro, J.; Castanol, N.; Chacón, E.; Chatelain, C.; Dullinger, S.; Ebel, A. L.; Figueiredo, E.; Fuentes, N.; Genovesi, P.; Groom, Q. J.; Henderson, L.; Inderjit, Dr.; Kupriyanov, A.; Masciadri, S.; Maurel, N.; Meerman, J.; Morozova, O.; Moser, D.; Nickrent, D. L.; Nowak, P. M.; Pagad, S.; Patzelt, A.; Pelser, P. B.; Seebens, H.; Shu, W.-S.; Thomas, J.; Velayos, M.; Weber, E.; Wieringa, J. J.; Baptiste, M. P.; van Kleunen, M.

    2017-01-01

    Roč. 89, č. 3 (2017), s. 203-274 ISSN 0032-7786 R&D Projects: GA ČR GB14-36079G Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : GloNAF * alien plants * biogeography Subject RIV: EH - Ecology, Behaviour OBOR OECD: Plant sciences, botany Impact factor: 3.000, year: 2016

  3. An assessment of the effectiveness of a large, national-scale invasive alien plant control strategy in South Africa

    CSIR Research Space (South Africa)

    Van Wilgen, BW

    2012-04-01

    Full Text Available extent of invasive species control operations, assessments of the effectiveness of biological control, and smaller-scale studies. The 19 most important invasive taxa, mainly trees, in terrestrial biomes were identified. The effectiveness of control...

  4. Do David and Goliath Play the Same Game? Explanation of the Abundance of Rare and Frequent Invasive Alien Plants in Urban Woodlands in Warsaw, Poland.

    Science.gov (United States)

    Obidziński, Artur; Mędrzycki, Piotr; Kołaczkowska, Ewa; Ciurzycki, Wojciech; Marciszewska, Katarzyna

    2016-01-01

    Invasive Alien Plants occur in numbers differing by orders of magnitude at subsequent invasion stages. Effective sampling and quantifying niches of rare invasive plants are quite problematic. The aim of this paper is an estimation of the influence of invasive plants frequency on the explanation of their local abundance. We attempted to achieve it through: (1) assessment of occurrence of self-regenerating invasive plants in urban woodlands, (2) comparison of Random Forest modelling results for frequent and rare species. We hypothesized that the abundance of frequent species would be explained better than that of rare ones and that both rare and frequent species share a common hierarchy of the most important determinants. We found 15 taxa in almost two thirds of 1040 plots with a total number of 1068 occurrences. There were recorded 6 taxa of high frequency-Prunus serotina, Quercus rubra, Acer negundo, Robinia pseudoacacia, Impatiens parviflora and Solidago spp.-and 9 taxa of low frequency: Acer saccharinum, Amelanchier spicata, Cornus spp., Fraxinus spp., Parthenocissus spp., Syringa vulgaris, Echinocystis lobata, Helianthus tuberosus, Reynoutria spp. Random Forest's models' quality grows with the number of occurrences of frequent taxa but not of the rare ones. Both frequent and rare taxa share a similar hierarchy of predictors' importance: Land use > Tree stand > Seed source and, for frequent taxa, Forest properties as well. We conclude that there is an 'explanation jump' at higher species frequencies, but rare species are surprisingly similar to frequent ones in their determinant's hierarchy, with differences conforming with their respective stages of invasion.

  5. Do David and Goliath Play the Same Game? Explanation of the Abundance of Rare and Frequent Invasive Alien Plants in Urban Woodlands in Warsaw, Poland.

    Directory of Open Access Journals (Sweden)

    Artur Obidziński

    Full Text Available Invasive Alien Plants occur in numbers differing by orders of magnitude at subsequent invasion stages. Effective sampling and quantifying niches of rare invasive plants are quite problematic. The aim of this paper is an estimation of the influence of invasive plants frequency on the explanation of their local abundance. We attempted to achieve it through: (1 assessment of occurrence of self-regenerating invasive plants in urban woodlands, (2 comparison of Random Forest modelling results for frequent and rare species. We hypothesized that the abundance of frequent species would be explained better than that of rare ones and that both rare and frequent species share a common hierarchy of the most important determinants. We found 15 taxa in almost two thirds of 1040 plots with a total number of 1068 occurrences. There were recorded 6 taxa of high frequency-Prunus serotina, Quercus rubra, Acer negundo, Robinia pseudoacacia, Impatiens parviflora and Solidago spp.-and 9 taxa of low frequency: Acer saccharinum, Amelanchier spicata, Cornus spp., Fraxinus spp., Parthenocissus spp., Syringa vulgaris, Echinocystis lobata, Helianthus tuberosus, Reynoutria spp. Random Forest's models' quality grows with the number of occurrences of frequent taxa but not of the rare ones. Both frequent and rare taxa share a similar hierarchy of predictors' importance: Land use > Tree stand > Seed source and, for frequent taxa, Forest properties as well. We conclude that there is an 'explanation jump' at higher species frequencies, but rare species are surprisingly similar to frequent ones in their determinant's hierarchy, with differences conforming with their respective stages of invasion.

  6. Identifying barriers to effective management of widespread invasive alien trees: Prosopis species (mesquite) in South Africa as a case study

    CSIR Research Space (South Africa)

    Shackleton, RT

    2016-05-01

    Full Text Available and in some cases improve the benefits that some invasive species can provide. This study assesses the barriers that hinder the effective management of widespread tree invasions, drawing insights from a case study of invasions of Prosopis species (mesquite...

  7. Changes in defense of an alien plant Ambrosia artemisiifolia before and after the invasion of a native specialist enemy Ophraella communa.

    Directory of Open Access Journals (Sweden)

    Yuya Fukano

    Full Text Available The evolution of increased competitive ability hypothesis (EICA predicts that when alien plants are free from their natural enemies they evolve lower allocation to defense in order to achieve a higher growth rate. If this hypothesis is true, the converse implication would be that the defense against herbivory could be restored if a natural enemy also becomes present in the introduced range. We tested this scenario in the case of Ambrosia artemisiifolia (common ragweed - a species that invaded Japan from North America. We collected seeds from five North American populations, three populations in enemy free areas of Japan and four populations in Japan where the specialist herbivore Ophraella communa naturalized recently. Using plants grown in a common garden in Japan, we compared performance of O. communa with a bioassay experiment. Consistent with the EICA hypothesis, invasive Japanese populations of A. artemisiifolia exhibited a weakened defense against the specialist herbivores and higher growth rate than native populations. Conversely, in locations where the herbivore O. communa appeared during the past decade, populations of A. artemisiifolia exhibited stronger defensive capabilities. These results strengthen the case for EICA and suggest that defense levels of alien populations can be recuperated rapidly after the native specialist becomes present in the introduced range. Our study implies that the plant defense is evolutionary labile depending on plant-herbivore interactions.

  8. DNA-based identification of invasive alien species in relation to Canadian federal policy and law, and the basis of rapid-response management.

    Science.gov (United States)

    Thomas, Vernon G; Hanner, Robert H; Borisenko, Alex V

    2016-11-01

    Managing invasive alien species in Canada requires reliable taxonomic identification as the basis of rapid-response management. This can be challenging, especially when organisms are small and lack morphological diagnostic features. DNA-based techniques, such as DNA barcoding, offer a reliable, rapid, and inexpensive toolkit for taxonomic identification of individual or bulk samples, forensic remains, and even environmental DNA. Well suited for this requirement, they could be more broadly deployed and incorporated into the operating policy and practices of Canadian federal departments and should be authorized under these agencies' articles of law. These include Fisheries and Oceans Canada, Canadian Food Inspection Agency, Transport Canada, Environment Canada, Parks Canada, and Health Canada. These efforts should be harmonized with the appropriate provisions of provincial jurisdictions, for example, the Ontario Invasive Species Act. This approach necessitates that a network of accredited, certified laboratories exists, and that updated DNA reference libraries are readily accessible. Harmonizing this approach is vital among Canadian federal agencies, and between the federal and provincial levels of government. Canadian policy and law must also be harmonized with that of the USA when detecting, and responding to, invasive species in contiguous lands and waters. Creating capacity in legislation for use of DNA-based identifications brings the authority to fund, train, deploy, and certify staff, and to refine further developments in this molecular technology.

  9. Alien invasions in aquatic ecosystems: toward an understanding of brook trout invasions and potential impacts on inland cutthroat trout in western North America

    Science.gov (United States)

    Jason B. Dunham; Susan B. Adams; Robert E. Schroeter; Douglas C. Novinger

    2002-01-01

    Experience from case studies of biological invasions in aquatic ecosystems has motivated a set of proposed empirical “rules” for understanding patterns of invasion and impacts on native species. Further evidence is needed to better understand these patterns, and perhaps contribute to a useful predictive theory of invasions. We reviewed the case of brook trout (

  10. Colonization history, host distribution, anthropogenic influence and landscape features shape populations of white pine blister rust, an invasive alien tree pathogen.

    Science.gov (United States)

    Brar, Simren; Tsui, Clement K M; Dhillon, Braham; Bergeron, Marie-Josée; Joly, David L; Zambino, P J; El-Kassaby, Yousry A; Hamelin, Richard C

    2015-01-01

    White pine blister rust is caused by the fungal pathogen Cronartium ribicola J.C. Fisch (Basidiomycota, Pucciniales). This invasive alien pathogen was introduced into North America at the beginning of the 20th century on pine seedlings imported from Europe and has caused serious economic and ecological impacts. In this study, we applied a population and landscape genetics approach to understand the patterns of introduction and colonization as well as population structure and migration of C. ribicola. We characterized 1,292 samples of C. ribicola from 66 geographic locations in North America using single nucleotide polymorphisms (SNPs) and evaluated the effect of landscape features, host distribution, and colonization history on the structure of these pathogen populations. We identified eastern and western genetic populations in North America that are strongly differentiated. Genetic diversity is two to five times higher in eastern populations than in western ones, which can be explained by the repeated accidental introductions of the pathogen into northeastern North America compared with a single documented introduction into western North America. These distinct genetic populations are maintained by a barrier to gene flow that corresponds to a region where host connectivity is interrupted. Furthermore, additional cryptic spatial differentiation was identified in western populations. This differentiation corresponds to landscape features, such as mountain ranges, and also to host connectivity. We also detected genetic differentiation between the pathogen populations in natural stands and plantations, an indication that anthropogenic movement of this pathogen still takes place. These results highlight the importance of monitoring this invasive alien tree pathogen to prevent admixture of eastern and western populations where different pathogen races occur.

  11. Colonization history, host distribution, anthropogenic influence and landscape features shape populations of white pine blister rust, an invasive alien tree pathogen.

    Directory of Open Access Journals (Sweden)

    Simren Brar

    Full Text Available White pine blister rust is caused by the fungal pathogen Cronartium ribicola J.C. Fisch (Basidiomycota, Pucciniales. This invasive alien pathogen was introduced into North America at the beginning of the 20th century on pine seedlings imported from Europe and has caused serious economic and ecological impacts. In this study, we applied a population and landscape genetics approach to understand the patterns of introduction and colonization as well as population structure and migration of C. ribicola. We characterized 1,292 samples of C. ribicola from 66 geographic locations in North America using single nucleotide polymorphisms (SNPs and evaluated the effect of landscape features, host distribution, and colonization history on the structure of these pathogen populations. We identified eastern and western genetic populations in North America that are strongly differentiated. Genetic diversity is two to five times higher in eastern populations than in western ones, which can be explained by the repeated accidental introductions of the pathogen into northeastern North America compared with a single documented introduction into western North America. These distinct genetic populations are maintained by a barrier to gene flow that corresponds to a region where host connectivity is interrupted. Furthermore, additional cryptic spatial differentiation was identified in western populations. This differentiation corresponds to landscape features, such as mountain ranges, and also to host connectivity. We also detected genetic differentiation between the pathogen populations in natural stands and plantations, an indication that anthropogenic movement of this pathogen still takes place. These results highlight the importance of monitoring this invasive alien tree pathogen to prevent admixture of eastern and western populations where different pathogen races occur.

  12. Alien plants introduced by different pathways differ in invasion success: unintentional introductions as a threat to natural areas

    Czech Academy of Sciences Publication Activity Database

    Pyšek, Petr; Jarošík, Vojtěch; Pergl, Jan

    2011-01-01

    Roč. 6, č. 9 (2011), e24890 E-ISSN 1932-6203 R&D Projects: GA MŠk LC06073; GA ČR(CZ) GAP504/11/1028 Institutional research plan: CEZ:AV0Z60050516 Keywords : plant invasions * pathways * naturalization and invasion Subject RIV: EF - Botanics Impact factor: 4.092, year: 2011

  13. ALIEN SPECIES: THEIR ROLE IN AMPHIBIAN POPULATION DECLINES AND RESTORATION

    Science.gov (United States)

    Alien species (also referred to as exotic, invasive, introduced, or normative species) have been implicated as causal agents in population declines of many amphibian species. Herein, we evaluate the relative contributions of alien species and other factors in adversely affecting ...

  14. Environmental implications of plastic debris in marine settings—entanglement, ingestion, smothering, hangers-on, hitch-hiking and alien invasions

    Science.gov (United States)

    Gregory, Murray R.

    2009-01-01

    Over the past five or six decades, contamination and pollution of the world’s enclosed seas, coastal waters and the wider open oceans by plastics and other synthetic, non-biodegradable materials (generally known as ‘marine debris’) has been an ever-increasing phenomenon. The sources of these polluting materials are both land- and marine-based, their origins may be local or distant, and the environmental consequences are many and varied. The more widely recognized problems are typically associated with entanglement, ingestion, suffocation and general debilitation, and are often related to stranding events and public perception. Among the less frequently recognized and recorded problems are global hazards to shipping, fisheries and other maritime activities. Today, there are rapidly developing research interests in the biota attracted to freely floating (i.e. pelagic) marine debris, commonly known as ‘hangers-on and hitch-hikers’ as well as material sinking to the sea floor despite being buoyant. Dispersal of aggressive alien and invasive species by these mechanisms leads one to reflect on the possibilities that ensuing invasions could endanger sensitive, or at-risk coastal environments (both marine and terrestrial) far from their native habitats. PMID:19528053

  15. An approach to the development of a national strategy for controlling invasive alien plant species: The case of Parthenium hysterophorus in South Africa

    Directory of Open Access Journals (Sweden)

    Colette Terblanche

    2016-06-01

    Full Text Available Invasive alien species require co-ordinated strategic management if negative impacts are to be effectively avoided. Here we describe a strategy for the management of Parthenium hysterophorus L. (Asteraceae in South Africa. P. hysterophorus is an annual herb native to tropical America, which has become invasive in over 30 countries. The strategy sets goals for (1 the prevention of spread to new areas; (2 local eradication of isolated populations; (3 containment in areas where eradication is not possible; and (4 actions to protect assets where containment is no longer an option. We developed both a national strategy to set policy and to monitor progress towards goals at a national level and an implementation plan to set goals and timeframes for their achievement at local levels. It is not clear, at this stage, whether or not the goals of the strategy are achievable because implementation will face many challenges arising from ecological features of the target plant, social and cultural practices that will influence management, inadequate levels of funding and multiple political considerations. Our strategy proposes regular assessment using high-level indicators, a practice that is widely recognised as essential but seldom implemented at a national scale. Because the outcomes are uncertain, it is vital that regular monitoring of outcomes should be instituted from the start, so that both appropriate adjustments can be made to the strategy and lessons for the implementation of similar strategies elsewhere can be derived.

  16. Alien Pathogens on the Horizon

    NARCIS (Netherlands)

    Roy, Helen E.; Hesketh, Helen; Purse, Bethan V.; Eilenberg, Jørgen; Santini, Alberto; Scalera, Riccardo; Stentiford, Grant D.; Adriaens, Tim; Bacela-Spychalska, Karolina; Bass, David; Beckmann, Katie M.; Bessell, Paul; Bojko, Jamie; Booy, Olaf; Cardoso, Ana Cristina; Essl, Franz; Groom, Quentin; Harrower, Colin; Kleespies, Regina; Martinou, Angeliki F.; Oers, van Monique M.; Peeler, Edmund J.; Pergl, Jan; Rabitsch, Wolfgang; Roques, Alain; Schaffner, Francis; Schindler, Stefan; Schmidt, Benedikt R.; Schönrogge, Karsten; Smith, Jonathan; Solarz, Wojciech; Stewart, Alan; Stroo, Arjan; Tricarico, Elena; Turvey, Katharine M.A.; Vannini, Andrea; Vilà, Montserrat; Woodward, Stephen; Wynns, Anja Amtoft; Dunn, Alison M.

    2017-01-01

    According to the Convention on Biological Diversity, by 2020 invasive alien species (IAS) should be identified and their impacts assessed, so that species can be prioritized for implementation of appropriate control strategies and measures put in place to manage invasion pathways. For one quarter of

  17. Strategy to control the invasive alien tree Miconia calvescens in Pacific islands: Eradication, containment or something else?

    Science.gov (United States)

    Meyer, Jean-Yves; Loope, Lloyd; Goarant, Anne-Claire; Veitch, C.R.; Clout, M.N.; Towns, D. R.

    2011-01-01

    Miconia calvescens (Melastomataceae) is a notorious plant invader in the tropical islands of French Polynesia, Hawaii and New Caledonia. A small tree native to Central and South America, it was first introduced as an ornamental in private botanic gardens in Tahiti (1937), Honolulu (1961), and Nouméa (1970s) where it escaped, became naturalised, and formed dense monospecific stands. More than 80,000 ha are currently invaded in French Polynesia, 10,000 ha in the Hawaiian Islands and 140 ha in New Caledonia. Control programmes have been under way in the Hawaiian Islands (Oahu, Maui, Hawaii, Kauai) and French Polynesia (Raiatea, Tahaa, Nuku Hiva, Fatu Hiva) since the early 1990s, and in New Caledonia (Province Sud) since 2006. Despite more than 15 years of intensive control efforts and millions of plants destroyed, eradication has not been achieved in any of these islands, mainly because the species has multiple features that thwart its elimination (e.g., prolific seed production, active dispersal by alien and native frugivorous birds, large and persistent soil seed bank, shade-tolerance), combined with the difficulty of detecting and destroying plants on rough terrain and steep slopes, insufficient control frequency, and limited financial and human resources. Miconia’s life cycle requires at least four years growth from seedling to fruiting. Consequently, prevention of fruit production may be an effective management strategy for small populations. This “juvenilization” process may allow the eradication of small populations when carefully conducted over a quarter century. 

  18. Catalogue of alien plants of the Czech Republic (2nd edition): checklist update, taxonomic diversity and invasion patterns

    Czech Academy of Sciences Publication Activity Database

    Pyšek, Petr; Danihelka, Jiří; Sádlo, Jiří; Chrtek, Jindřich; Chytrý, M.; Jarošík, Vojtěch; Kaplan, Zdeněk; Krahulec, František; Moravcová, Lenka; Pergl, Jan; Štajerová, Kateřina; Tichý, L.

    2012-01-01

    Roč. 84, č. 2 (2012), s. 155-255 ISSN 0032-7786 R&D Projects: GA ČR(CZ) GAP504/11/1028 Institutional support: RVO:67985939 Keywords : invasive plants * checklist * Czech Republic Subject RIV: EF - Botanics Impact factor: 2.833, year: 2012

  19. Niche-based modelling as a tool for predicting the risk of alien plant invasions at a global scale

    Czech Academy of Sciences Publication Activity Database

    Thuiller, W.; Richardson, D. M.; Pyšek, Petr; Midgley, G. F.; Hughes, G. O.; Rouget, M.

    2005-01-01

    Roč. 11, - (2005), s. 2234-2250 ISSN 1354-1013 R&D Projects: GA ČR GA206/03/1216 Institutional research plan: CEZ:AV0Z60050516 Keywords : bioclimatic modelling * biological invasions * risk assessment Subject RIV: EF - Botanics Impact factor: 4.075, year: 2005

  20. Where do they come from and where do they go? European natural habitats as donors of invasive alien plants globally

    Czech Academy of Sciences Publication Activity Database

    Kalusová, V.; Chytrý, M.; Kartesz, J. T.; Nishino, M.; Pyšek, Petr

    2013-01-01

    Roč. 19, č. 2 (2013), s. 199-214 ISSN 1366-9516 R&D Projects: GA ČR(CZ) GAP505/11/1112 Institutional support: RVO:67985939 Keywords : habitat * invasibility * Europe Subject RIV: EF - Botanics Impact factor: 5.469, year: 2013

  1. Ecological impacts of invasive alien plants: a meta-analysis of their effects on species, communities and ecosystems

    Czech Academy of Sciences Publication Activity Database

    Vila, M.; Espinar, J. L.; Hejda, Martin; Hulme, P. E.; Jarošík, Vojtěch; Maron, J. L.; Pergl, Jan; Schaffner, U.; Sun, Y.; Pyšek, Petr

    2011-01-01

    Roč. 14, č. 7 (2011), s. 702-708 ISSN 1461-023X R&D Projects: GA MŠk LC06073; GA ČR GA206/09/0563 Grant - others:European Comission(XE) 7E09072-(KBBE-212827) Institutional research plan: CEZ:AV0Z60050516 Keywords : biological invasions * impact * organisational level Subject RIV: EF - Botanics Impact factor: 17.557, year: 2011

  2. Contrasting patterns in the invasions of European terrestrial and freshwater habitats by alien plants, insects and vertebrates

    Czech Academy of Sciences Publication Activity Database

    Pyšek, Petr; Bacher, S.; Chytrý, M.; Jarošík, Vojtěch; Wild, Jan; Celesti-Grapow, L.; Gassó, N.; Kenis, M.; Lambdon, P. W.; Nentwig, W.; Pergl, Jan; Roques, A.; Sádlo, Jiří; Solarz, W.; Vila, M.; Hulme, P. E.

    2010-01-01

    Roč. 19, č. 3 (2010), s. 317-331 ISSN 1466-822X R&D Projects: GA MŠk LC06073 Grant - others:ALARM(XE) GOCE-CT-2003-506675; European Comission(XE) SSPI-CT-2003-511202 Institutional research plan: CEZ:AV0Z60050516 Keywords : biological invasions * habitat affinities * Europe Subject RIV: EF - Botanics Impact factor: 5.273, year: 2010

  3. Survey and documentation of the potential and actual invasive alien plant species and other biological threats to biodiversity in Awash National Park, Ethiopia

    Directory of Open Access Journals (Sweden)

    Sebsebe DEMISSEW

    2011-01-01

    Full Text Available The study was conducted at the Awash National Park (ANP Ethiopia, todocument Invasive Alien Species (IAS and to assess the spread of Prosopis juliflora (Sw. DC. A total of 64 sample plots were laid systematically along the altitudinal gradient of 750 to 1916 m.Potential IAS were recorded. IAS which may threaten biodiversity of the park includes species such as Prosopis juliflora, Parthenium hysterophorus L., Cryptostegia grandiflora Roxb. ex R. Br., Parkinsonia aculeata L., Senna occidentalis (L. Link, Datura ferox L. and Xanthium strumarium L. Except P. juliflora and P. hysterophorus, all others were not recorded in Ethiopia as IAS. P.juliflora was recorded in three plots with cover of 1% to 10%. P. juliflora was also found spread in different parts of the park particularly following the route of cattle movement. P. hysterophoruswas recorded in and around nine sample plots. Plot 46, 47 and 48 werehighly infested by P. hysterophorus which covered more than 60, 70 and 80% of the ground layer respectively. C. grandiflora was recorded in 11 plots with cover ranging from 1% to 35%. In view of all the natural as well as anthropogenic threats to the biodiversity of the Park, the ANP is at high risk. The rich biodiversity needsimmediate management intervention.

  4. Invasive alien trees and water resources in South Africa: case studies of the costs and benefits of management

    CSIR Research Space (South Africa)

    Le Maitre, David C

    2002-05-01

    Full Text Available trees and water resources in South Africa: case studies of the costs and benefits of management D.C. Le Maitrea,*, B.W. van Wilgena, C.M. Gelderbloma, C. Baileyb, R.A. Chapmana, J.A. Nela aCSIR Division of Water, Environment and Forestry Technology, P....O. Box 320, Stellenbosch 7599, South Africa bCSIR Division of Water, Environment and Forestry Technology, P.O. Box 395, Pretoria 0001, South Africa Received 12 April 2000; received in revised form 2 January 2001; accepted 15 January 2001 Abstract Invasive...

  5. Amorpha fruticosa – A Noxious Invasive Alien Plant in Europe or a Medicinal Plant against Metabolic Disease?

    Directory of Open Access Journals (Sweden)

    Ekaterina Kozuharova

    2017-06-01

    Full Text Available Amorpha fruticosa L. (Fabaceae is a shrub native to North America which has been cultivated mainly for its ornamental features, honey plant value and protective properties against soil erosion. It is registered amongst the most noxious invasive species in Europe. However, a growing body of scientific literature also points to the therapeutic potential of its chemical constituents. Due to the fact that A. fruticosa is an aggressive invasive species, it can provide an abundant and cheap resource of plant chemical constituents which can be utilized for therapeutic purposes. Additionally, exploitation of the biomass for medicinal use might contribute to relieving the destructive impact of this species on natural habitats. The aim of this review is to provide a comprehensive summary and systematize the state-of-the-art in the knowledge of the phytochemical composition and the potential of A. fruticosa in disease treatment and prevention, with especial emphasis on diabetes and metabolic syndrome. Also reviewed are aspects related to potential toxicity of A. fruticosa which has not yet been systematically evaluated in human subjects.

  6. Naturalized alien flora of the world

    NARCIS (Netherlands)

    Pyšek, Petr; Pergl, Jan; Essl, Franz; Lenzner, Bernd; Dawson, Wayne; Kreft, Holger; Weigelt, Patrick; Winter, Marten; Kartesz, John; Nishino, Misako; Antonova, Liubov A.; Barcelona, Julie F.; Cabezas, Francisco J.; Cárdenas, Dairon; Cárdenas-Toro, Juliana; Castaño, Nicolás; Chacón, Eduardo; Chatelain, Cyrille; Dullinger, Stefan; Ebel, Aleksandr L.; Figueiredo, Estrela; Fuentes, Nicol; Genovesi, Piero; Groom, Quentin J.; Henderson, Lesley; Inderjit,; Kupriyanov, Andrey; Masciadri, Silvana; Maurel, Noëlie; Meerman, Jan; Morozova, Olga; Moser, Dietmar; Nickrent, Daniel L.; Nowak, Pauline M.; Pagad, Shyama; Patzelt, Annette; Pelser, Pieter B.; Seebens, Hanno; Shu, Wen Sheng; Thomas, Jacob; Velayos, Mauricio; Weber, Ewald; Wieringa, Jan J.; Baptiste, María P.; Kleunen, Van Mark

    2017-01-01

    Using the recently built Global Naturalized Alien Flora (GloNAF) database, containing data on the distribution of naturalized alien plants in 483 mainland and 361 island regions of the world, we describe patterns in diversity and geographic distribution of naturalized and invasive plant species,

  7. The opportunity cost of not utilising the woody invasive alien plant species in the Kouga, Krom and Baviaans catchments in South Africa

    Directory of Open Access Journals (Sweden)

    Thulile Vundla

    2016-12-01

    Full Text Available This study estimates the opportunity costs of using woody invasive alien plants (IAPs for value-added products by estimating the net economic return from the value-added industries in South Africa. By 2008, IAPs were estimated at the national level to cover an area of 1 813 million condensed hectares in South Africa. A market has formed around their use for value-added products (VAP like charcoal, firewood and timber in the Kouga, Kromme and Baviaans River catchments in the Eastern Cape province of South Africa. The net economic return from these value-added industries was estimated for the purpose of several management scenarios, and was then used to estimate the opportunity costs if they were not used. A system dynamics model was used to value and analyse the Net Present Value of clearing in the study area and to estimate the opportunity cost of the non-use of VAP. The study showed that the inclusion of VAPs in the project would yield higher net present values for clearing. The findings from this study suggest that a cofinance option of the total economic returns from VAP for clearing costs is the best management scenario for reducing the costs of clearing and maximising the net economic returns from clearing. The net economic returns of VAPs by 2030 are estimated at R23 million without the co-finance option and R26 million with the option. The cumulative net income from VAPs with co-financing over the period of valuation is estimated to be R609 million.

  8. Phyloecology of urban alien floras

    Czech Academy of Sciences Publication Activity Database

    Ricotta, C.; La Sorte, F. A.; Pyšek, Petr; Rapson, G. L.; Celesti-Grapow, L.; Thompson, K.

    2009-01-01

    Roč. 97, č. 6 (2009), s. 1243-1251 ISSN 0022-0477 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60050516 Keywords : urban aliens * biological invasions * phylogenetic similarity Subject RIV: EF - Botanics Impact factor: 4.690, year: 2009

  9. ALIENS IN WESTERN STREAM ECOSYSTEMS

    Science.gov (United States)

    The USEPA's Environmental Monitoring and Assessment Program conducted a five year probability sample of permanent mapped streams in 12 western US states. The study design enables us to determine the extent of selected riparian invasive plants, alien aquatic vertebrates, and some ...

  10. Alien species in the Finnish weed flora

    Directory of Open Access Journals (Sweden)

    T. HYVÖNEN

    2008-12-01

    Full Text Available The present study aimed at assessing the invasion of alien weed species in Finland based on a review of their occurrence in the Finnish weed flora. The evaluation was conducted for the three phases of the invasion process, i.e. introduction, naturalization and invasion. The literature review revealed that 815 alien weed species occur in Finland of which 314 are regarded as naturalized. Based on their occurrence in different climate zones, the risk of naturalization of new harmful alien weed species was deemed low for those species not currently found in Finland, but higher for species occurring as casual aliens in Finland. In the latter group, 10 species of concern were detected. Exploration of the distribution patterns of naturalized species within Finland revealed species occupancy to be dependent on the residence time of the species. Established neophytes can be expected to extend their ranges and to increase occupation of agricultural habitats in the future.;

  11. Predicting vibration-induced displacement for a resonant friction slider

    DEFF Research Database (Denmark)

    Fidlin, A.; Thomsen, Jon Juel

    2001-01-01

    A mathematical model is set up to quantify vibration-induced motions of a slider, sandwiched between friction layers with different coefficients of friction, and equipped with an imbedded resonator that oscillates at high frequency and small amplitude. This model is highly nonlinear, involving non...

  12. Modified technique of using conventional slider boat for liquid phase ...

    Indian Academy of Sciences (India)

    Unknown

    after baking. After HCl treatment it was repeatedly washed in deionized water and finally dried. To load the boat, the solid mass was placed over freshly cleaned surface of a source silicon wafer placed in first groove of slider unit B with both the units B and C mounted on. A as seen in figure 2a. The process tube was again ...

  13. Modified technique of using conventional slider boat for liquid phase ...

    Indian Academy of Sciences (India)

    Epitaxial layers of silicon are grown on single crystal Si-substrate from a solution of silicon in indium using conventional graphite slider boat technique. The important problems of natural convection due to lower density of silicon compared to indium, poor wetting of substrate due to high angle of contact of indium solution on ...

  14. Options in dealing with marine alien species

    NARCIS (Netherlands)

    Pelt-Heerschap, van H.M.L.; Sneekes, A.C.; Foekema, E.M.

    2015-01-01

    Invasive species can have strong impact on the local ecosystem, not only substantial impact on the local ecosystem, but also on economy and human health. This review on marine alien species outlines aspects of prevention, eradication and control strategies. When managing invasive species, prevention

  15. Widespread plant species: Natives versus aliens in our changing world

    Science.gov (United States)

    Stohlgren, T.J.; Pysek, P.; Kartesz, J.; Nishino, M.; Pauchard, A.; Winter, M.; Pino, J.; Richardson, D.M.; Wilson, J.R.U.; Murray, B.R.; Phillips, M.L.; Ming-yang, L.; Celesti-Grapow, L.; Font, X.

    2011-01-01

    Estimates of the level of invasion for a region are traditionally based on relative numbers of native and alien species. However, alien species differ dramatically in the size of their invasive ranges. Here we present the first study to quantify the level of invasion for several regions of the world in terms of the most widely distributed plant species (natives vs. aliens). Aliens accounted for 51.3% of the 120 most widely distributed plant species in North America, 43.3% in New South Wales (Australia), 34.2% in Chile, 29.7% in Argentina, and 22.5% in the Republic of South Africa. However, Europe had only 1% of alien species among the most widespread species of the flora. Across regions, alien species relative to native species were either as well-distributed (10 comparisons) or more widely distributed (5 comparisons). These striking patterns highlight the profound contribution that widespread invasive alien plants make to floristic dominance patterns across different regions. Many of the most widespread species are alien plants, and, in particular, Europe and Asia appear as major contributors to the homogenization of the floras in the Americas. We recommend that spatial extent of invasion should be explicitly incorporated in assessments of invasibility, globalization, and risk assessments. ?? 2011 Springer Science+Business Media B.V.

  16. Widespread plant species: natives vs. aliens in our changing world

    Science.gov (United States)

    Stohlgren, Thomas J.; Pyšek, Petr; Kartesz, John; Nishino, Misako; Pauchard, Aníbal; Winter, Marten; Pino, Joan; Richardson, David M.; Wilson, John R.U.; Murray, Brad R.; Phillips, Megan L.; Ming-yang, Li; Celesti-Grapow, Laura; Font, Xavier

    2011-01-01

    Estimates of the level of invasion for a region are traditionally based on relative numbers of native and alien species. However, alien species differ dramatically in the size of their invasive ranges. Here we present the first study to quantify the level of invasion for several regions of the world in terms of the most widely distributed plant species (natives vs. aliens). Aliens accounted for 51.3% of the 120 most widely distributed plant species in North America, 43.3% in New South Wales (Australia), 34.2% in Chile, 29.7% in Argentina, and 22.5% in the Republic of South Africa. However, Europe had only 1% of alien species among the most widespread species of the flora. Across regions, alien species relative to native species were either as well-distributed (10 comparisons) or more widely distributed (5 comparisons). These striking patterns highlight the profound contribution that widespread invasive alien plants make to floristic dominance patterns across different regions. Many of the most widespread species are alien plants, and, in particular, Europe and Asia appear as major contributors to the homogenization of the floras in the Americas. We recommend that spatial extent of invasion should be explicitly incorporated in assessments of invasibility, globalization, and risk assessments.

  17. IN DEFENSE OF ALIENATION.

    Science.gov (United States)

    KENISTON, KENNETH

    THE TERM ALIENATION IS IN IMMINENT DANGER OF BECOMING PART OF THE VOCABULARY OF POLITE ABUSE. ONE OF THE WORD'S VIRTUES IS ITS AMBIGUITY. IN THE SOCIOLOGICAL TRADITION, ALIENATION REFERS TO A STRUCTURAL CONDITION. PEOPLE ARE ALIENATED MORE OR LESS AGAINST THEIR WILL. IN THE PSYCHOLOGICAL MEANING, ALIENATION PRESUPPOSES SOME INNER ATTITUDE,…

  18. Analysis of partially textured slider and journal bearing

    Science.gov (United States)

    Rao, T. V. V. L. N.; Rani, A. M. A.; Nagarajan, T.; Hashim, F. M.

    2012-06-01

    The partial texturing of bearing surfaces with different shapes of textures and at different locations is an effective approach to improve the performance of bearings. The present study examines the effects of texture configuration on improvement in load capacity and reduction in friction coefficient for slider and journal bearing. This work presents nondimensional pressure expressions for the partially textured slider and journal bearing. The nondimensional pressure expressions are derived taking into consideration of texture geometry and extent of partial texture on the bearing surface. The Reynolds boundary conditions are used in the analysis to predict nondimensional load capacity and coefficient of friction. Even for nominally parallel surfaces, partial texturing of bearing surfaces has a potential to generate load carrying capacity and reduce coefficient of friction.

  19. The coregulator Alien

    OpenAIRE

    Papaioannou, Maria; Melle, Christian; Baniahmad, Aria

    2007-01-01

    Alien has characteristics of a corepressor for selected members of the nuclear hormone receptor (NHR) superfamily and also for transcription factors involved in cell cycle regulation and DNA repair. Alien mediates gene silencing and represses the transactivation of specific NHRs and other transcription factors to modulate hormone response and cell proliferation. Alien is a highly conserved protein and is expressed in a wide variety of tissues. Knockout of the gene encoding Alien in mice is em...

  20. Slider Posture Effects on Air Bearing in a Heat-Assisted Magnetic Recording System

    Directory of Open Access Journals (Sweden)

    Kyaw Sett Myo

    2012-01-01

    Full Text Available This paper reports the effects of slider posture on the slider bearing in a heat-assisted magnetic recording (HAMR system with the direct simulation Monte Carlo (DSMC method. In this HAMR system, the heat issues on the slider bearings are assumed to be caused by a heated spot on the disk and/or slider body itself at various pitch angles. The simulation results show that with a heated spot on the disk, the air bearing pressure and air bearing force that acted on the slider surface will increase when the pitch angle becomes larger. It is also found that the bearing force increases with the heated spot size and the effects of a heated spot become more obvious at a larger pitch angle. On the other hand, the slider body temperature is observed to have a noticeable effect on air bearing pressure and force. The smaller pitch angle enlarges the tendency of bearing force variations with the slider temperature and makes the slider more sensitive to its temperature changes.

  1. Entropy generation in non-Newtonian fluid flow in a slider bearing

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Non-Newtonian effects on the static character- istics of one-dimensional slider bearings in the internal flow regime were investigated by ... and beating flexibility affected the performance characteristics of slot-entry journal bearing significantly. A slider bearing with second- and third-grade fluids as lubricant was analyzed.

  2. Nitrogen dynamics in land cleared of alien vegetation ( Acacia ...

    African Journals Online (AJOL)

    Fabaceae family), are currently cleared in South African catchments to reduce water loss and preserve streamflow, and for the restoration of the ecosystem. This study tested the hypothesis that clearing invasive alien vegetation may disturb the ...

  3. The role of the World Trade Organization and the 'three sisters' (the World Organisation for Animal Health, the International Plant Protection Convention and the Codex Alimentarius Commission) in the control of invasive alien species and the preservation of biodiversity.

    Science.gov (United States)

    Kahn, S; Pelgrim, W

    2010-08-01

    The missions of the World Organisation for Animal Health (OIE) include the design of surveillance and control methods for infectious transboundary animal diseases (including zoonoses), the provision of guarantees concerning animal health and animal production food safety, and the setting of standards for, and promotion of, animal welfare. The OIE role in setting standards for the sanitary safety of international trade in animals and animal products is formally recognised in the World Trade Organization (WTO) Agreement on the Application of Sanitary and Phytosanitary Measures (the SPS Agreement). While the primary focus of the OIE is on animal diseases and zoonoses, the OIE has also been working within the WTO framework to examine possible contributions the organisation can make to achieving the goals of the Convention on Biological Diversity, particularly to preventing the global spread of invasive alien species (IAS). However, at the present time, setting standards for invasive species (other than those connected to the cause and distribution of diseases listed by the OIE) is outside the OIE mandate. Any future expansion of the OIE mandate would need to be decided by its Members and resources (expertise and financial contributions) for an extended standard-setting work programme secured. The other international standard-setting organisations referenced by the SPS Agreement are the International Plant Protection Convention (IPPC) and the Codex Alimentarius Commission (CAC). The IPPC mandate and work programme address IAS and the protection of biodiversity. The CAC is not involved in this field.

  4. The coregulator Alien.

    Science.gov (United States)

    Papaioannou, Maria; Melle, Christian; Baniahmad, Aria

    2007-11-30

    Alien has characteristics of a corepressor for selected members of the nuclear hormone receptor (NHR) superfamily and also for transcription factors involved in cell cycle regulation and DNA repair. Alien mediates gene silencing and represses the transactivation of specific NHRs and other transcription factors to modulate hormone response and cell proliferation. Alien is a highly conserved protein and is expressed in a wide variety of tissues. Knockout of the gene encoding Alien in mice is embryonic lethal at a very early stage, indicating an important evolutionary role in multicellular organisms. From a mechanistic perspective, the corepressor function of Alien is in part mediated by histone deacetylase (HDAC) activity. In addition, Alien seems to modulate nucleosome assembly activity. This suggests that Alien is acting on chromatin not only through recruitment of histone-modifying activities, but also through enhancing nucleosome assembly.

  5. How many marine aliens in Europe?

    Directory of Open Access Journals (Sweden)

    Stelios Katsanevakis

    2013-01-01

    Full Text Available In the framework of the European Alien Species Information Network (EASIN; http://easin.jrc.ec.europa.eu/, an inventory of marine alienspecies in Europe was created by critically reviewing existing information in 34 global, European, regional and national databases. In total, 1369 marine alien species have been reported in the European seas (including 110 cryptogenic and 139 questionable species; this is a substantial increase from the 737 species previously reported in 2009 based on the DAISIE (Delivering Alien Invasive Species Inventories for Europe; http://www.europe-aliens.org dataset. Most of the reported species were invertebrates (63.3%, followed by chromists (13.7%, vertebrates (11.6%, and plants (10.1%. Mollusca is the most numerous phylum, followed by Arthropoda, Chordata, and Annelida. Thecountries with the highest reported numbers of marine alien species were Israel, Turkey, Italy, France, Egypt and Greece. A reporting bias is evident as efforts for monitoring and reporting alien species vary among countries.

  6. Biomagnetic monitoring of particulate matter (PM through leaves of an invasive alien plant Lantana camara in an Indo-Burma hot spot region

    Directory of Open Access Journals (Sweden)

    Prabhat Kumar Rai

    2016-03-01

    Full Text Available Present study was performed in urban forests of Aizawl, Mizoram, North East India falling under an Indo-Burma hot spot region of existing ecological relevance and pristine environment. Phyto-sociolology of invasive weeds has been performed and results revealed that Lantana camara was the most dominant invasive weed. Further, the air quality studies revealed high suspended particulate matter (SPM as well as respirable suspended particulate matter (RSPM in ambient air of Aizawl, Mizoram, North East India. Bio-magnetic monitoring through plant leaves has been recognised as recent thrust area in the field of particulate matter (PM science. We aimed to investigate that whether magnetic properties of Lantana camara leaves may act as proxy of PM pollution and hence an attempt towards it's sustainable management. Magnetic susceptibility (χ, Anhyste reticremanent magnetization (ARM and Saturation isothermal remanent magnetization (SIRM of Lantana camara plant leaves were assessed and concomitantly correlated these magnetic properties with ambient PM in order to screen this invasive plant which may act as proxy for ambient PM concentrations. Results revealed high χ, ARM, SIRM of Lantana camara leaves and moreover, these parameters were having significant and positive correlation with ambient SPM as well as RSPM. Therefore, present study recommended the use of Lantana camara as bio-magnetic monitor which may further have sustainable management implications of an invasive plant.

  7. The Alien University

    DEFF Research Database (Denmark)

    Bengtsen, Søren Smedegaard

    2018-01-01

    - they are alien. The conditions of universities today is not one of crisis and upheaval, as with the postmodern universities, it is one of night travel and exile. The alien university leaves behind the epistemological skirmishes of the postmodern university with all its rhetoric and knowledge activism. Thinking...... in the alien university is a move into a whirlpool of nothingness, a “nocturnal space”, where “[d]arkness fills it like a content; it is full, but full of the nothingness of everything.” (Levinas, 2001, p.53). In the alien university thinking is not situated, and instead of rhizomes, and assemblages of thought......, there is merely an imposing and nightly “swarming of points.” (ibid.). There is no place for the alien university, and exactly this exile of thought makes possible the move beyond postmodernism and the mentality of political crisis. The alien university is not in the future as such, but it is not entirely...

  8. Assessing effect of rainfall on rate of alien shrub expansion in a ...

    African Journals Online (AJOL)

    Assessing effect of rainfall on rate of alien shrub expansion in a southern African savanna. ... This is a novel finding suggesting that in water-limited savannas, pulses in rainfall may accelerate the spread of some invasive alien species. Keywords: aerial photography, invasion, Kyle Game Reserve, Lantana camara, patch ...

  9. INVASIVE ALIEN PLANTS ON DECAYING WOOD AND ON TREE-FALL DISTURBANCES IN FORESTS IN THE KARKONOSZE MTS (SUDETEN, SW POLAND

    Directory of Open Access Journals (Sweden)

    Monika Staniaszek-Kik

    2014-10-01

    Full Text Available Three invasive anthropophytes, i.e. two vascular plants Digitalis purpurea L. and Impatiens parviflora DC. as well as one moss Orthodontium lineare Schwägr, were recorded on decaying wood and tree-fall disturbances (pit-mound-root plate complex. It contributes only 1.9% to the flora of analyzed habitats (1.1% of moss flora, 2.9% of vascular plant flora and 3.5% of neophytes known in Sudeten Mts. They grew, sporadically and with a low frequency, on 3.5% of studied objects (on 3.1% of decaying logs and stumps and 5.6% of tree-fall disturbances in all types of forest communities in the area of Karkonosze National Park and in the vicinity. Nowadays, invasive neophytes do not pose a threat to diversity of endangered epixylic flora. Described habitats seem to be resistant to penetration by anthropophytes.

  10. Towards site-specific management of invasive alien trees based on the assessment of their impacts: the case of Robinia pseudoacacia

    Czech Academy of Sciences Publication Activity Database

    Sádlo, Jiří; Vítková, Michaela; Pergl, Jan; Pyšek, Petr

    2017-01-01

    Roč. 35, č. 1 (2017), s. 1-34 ISSN 1619-0033 R&D Projects: GA ČR GB14-36079G Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : Robinia pseudoacacia * plant invasion * management strategies Subject RIV: DO - Wilderness Conservation OBOR OECD: Environmental sciences (social aspects to be 5.7)

  11. Entropy generation in non-Newtonian fluid flow in a slider bearing

    Indian Academy of Sciences (India)

    In the present study, entropy production in flow fields due to slider bearings is formulated. The rate of entropy generation is computed for different fluid properties and geometric configurations of the slider bearing. In order to account for the non-Newtonian effect, a special type of third-grade fluid is considered. It is found that ...

  12. Changes in Hamstring Range of Motion After Neurodynamic Sciatic Sliders: A Critically Appraised Topic.

    Science.gov (United States)

    Bonser, Robert J; Hancock, Christy L; Hansberger, Bethany L; Loutsch, Rick A; Stanford, Eric K; Zeigel, Alli K; Baker, Russell T; May, James; Nasypany, Alan; Cheatham, Scott

    2017-07-01

    Clinical Scenario: Hamstring tightness is a common condition leading to dysfunctional or restricted movement that is often treated with stretching. Neurodynamics has been proposed as an alternative to stretching by targeting the neural system rather than muscle tissue. Focused Clinical Question: In an active population, what is the effect of using neurodynamic sliders compared with stretching on traditional measures of range of motion (ROM)? Summary of Key Findings: The authors of a well-designed study found that neurodynamic sliders were more effective than static stretching, while the authors of 2 less-well-designed studies reported no difference with static stretching or that proprioceptive neuromuscular facilitation stretching was more effective than neurodynamic sliders. Clinical Bottom Line: Evidence exists to support the use of neurodynamic sliders to increase measures of hamstring ROM in patients who present with limited hamstring flexibility; however, the effectiveness of neurodynamic sliders compared with traditional stretching is inconclusive. Strength of Recommendation: Grade B evidence exists that neurodynamic sliders perform as well as traditional stretching techniques at increasing measures of hamstring ROM in patients with limited hamstring flexibility.

  13. Play against alienation?

    DEFF Research Database (Denmark)

    Eichberg, Henning

    2018-01-01

    At the dawn of industrial modernity, in late eighteenth century, a shadow lay over Europe. Sensitive artists and intellectuals described the atmosphere as an encounter with something fremd – foreign, strange, alien. Karl Marx later introduced the term Entfremdung (estrangement, alienation......) into social philosophy. After being applied to the sphere of industrial class struggle, the concept was revitalized by philosophers of the Frankfurt School and again by the cultural revolt of 1968. Later on, however, the concept was dropped, even among critical philosophers. Was ‘alienation’ maybe too far...... from practical life? Wasn’t alienation contradicted by happy consumerist capitalism?...

  14. Highly invasive alien plant Reynoutria japonica Houtt. represents a novel source for pharmaceutical industry - evidence from phenolic profile and biological activity

    Directory of Open Access Journals (Sweden)

    Božin Biljana

    2017-01-01

    Full Text Available Reynoutria japonica is on the IUCN list of the Worlds’100 worst invasive species, but it is also, especially its rhizome, an integral part of traditional chinese medicine. The objective of this study was to determine the amount of selected phenolic compounds in rhizome, stems, leaves and inflorescence methanol extracts of this plant, their antioxidant and anticholinesterase activity. The chemical profile of the examined extracts was obtained by a high-performance liquid chromatography. In vitro assays on DPPH, OH and NO radicals were used to estimate antioxidant potential and Ellman’s method was applied for the determination of anticholinesterase activity. Leaves and rhizome extracts were found to be rich in rosmarinic and chlorogenic acid, and selected flavonoids. Resveratrol was exclusively present in rhizome and stems extracts. All the investigated extracts expressed certain antioxidant activity, where leaves extract was the most active. However, rhizome extract was the strongest inhibitor of acetylcholinesterase. These findings indicate that there is a possibility of R. japonica exploitation for the isolation of biologically active phenolic compounds used in pharmaceutical and food industry.

  15. Alien Noise Cancellation

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Full FEXT Cancellation. Expectation Maximization based Algorithms. Partial Cancellation. Optimal Choice of what to Cancel and what not to! Alien Noise Cancellation. Efficient Crosstalk channel estimation. In addition:

  16. Parental Alienation Syndrome

    Directory of Open Access Journals (Sweden)

    Fuat Torun

    2011-09-01

    Full Text Available Children who have been programmed by one parent to be alienated from the other parent are commonly seen in the context of child-custody disputes. Its primary manifestation is the child’s campaign of denigration against a parent, a campaign that has no justification. It is said to result from a combination of a programming (brainwashing parent’s indoctrinations and the child’s own contributions to the vilification of the targeted parent. Many evaluators use the term parental alienation syndrome to refer to the disorder engendered in such children. However, there is significant controversy going on about the validity of parental alienation syndrome. The purpose of this article has been to describe and help to differentiate parental alienation syndrome and abuse for mental health professionals working in the field, and discuss the arguments about the validity of this syndrome.

  17. Approaching invasive species in Madagascar | Kull | Madagascar ...

    African Journals Online (AJOL)

    invasive', the topic of invasive species has until recently received less attention here than in other island contexts. Some species, often alien to Madagascar and introduced by humans, have expanded their range rapidly and have had both ...

  18. Recreational trails as corridors for alien plants in the Rocky Mountains, USA

    Science.gov (United States)

    Wells, Floye H.; Lauenroth, William K.; Bradford, John B.

    2012-01-01

    Alien plant species often use areas of heavy human activity for habitat and dispersal. Roads and utility corridors have been shown to harbor more alien species than the surrounding vegetation and are therefore believed to contribute to alien plant persistence and spread. Recreational trails represent another corridor that could harbor alien species and aid their spread. Effective management of invasive species requires understanding how alien plants are distributed at trailheads and trails and how their dispersal may be influenced by native vegetation. Our overall goal was to investigate the distribution of alien plants at trailheads and trails in the Rocky Mountains of Colorado. At trailheads, we found that although the number of alien species was less than the number of native species, alien plant cover ( x̄=50%) did not differ from native plant cover, and we observed a large number of alien seedlings in the soil seed bank, suggesting that alien plants are a large component of trailhead communities and will continue to be so in the future. Along trails, we found higher alien species richness and cover on trail (as opposed to 4 m from the trail) in 3 out of 4 vegetation types, and we observed higher alien richness and cover in meadows than in other vegetation types. Plant communities at both trailheads and trails, as well as seed banks at trailheads, contain substantial diversity and abundance of alien plants. These results suggest that recreational trails in the Rocky Mountains of Colorado may function as corridors that facilitate the spread of alien species into wildlands. Our results suggest that control of alien plants should begin at trailheads where there are large numbers of aliens and that control efforts on trails should be prioritized by vegetation type.

  19. Quantitative genetics of plastron shape in slider turtles (Trachemys scripta).

    Science.gov (United States)

    Myers, Erin M; Janzen, Fredric J; Adams, Dean C; Tucker, John K

    2006-03-01

    Shape variation is widespread in nature and embodies both a response to and a source for evolution and natural selection. To detect patterns of shape evolution, one must assess the quantitative genetic underpinnings of shape variation as well as the selective environment that the organisms have experienced. Here we used geometric morphometrics to assess variation in plastron shell shape in 1314 neonatal slider turtles (Trachemys scripta) from 162 clutches of laboratory-incubated eggs from two nesting areas. Multivariate analysis of variance indicated that nesting area has a limited role in describing plastron shape variation among clutches, whereas differences between individual clutches were highly significant, suggesting a prominent clutch effect. The covariation between plastron shape and several possible maternal effect variables (yolk hormone levels and egg dimensions) was assessed for a subset of clutches and found to be negligible. We subsequently employed several recently proposed methods for estimating heritability from shape variables, and generalized a univariate approach to accommodate unequal sample sizes. Univariate estimates of shape heritability based on Procrustes distances yielded large values for both nesting populations (h2 approximately 0.86), and multivariate estimates of maximal additive heritability were also large for both nesting populations (h2max approximately 0.57). We also estimated the dominant trend in heritable shape change for each nesting population and found that the direction of shape evolution was not the same for the two sites. Therefore, although the magnitude of shape evolution was similar between nesting populations, the manner in which plastron shape is evolving is not. We conclude that the univariate approach for assessing quantitative genetic parameters from geometric morphometric data has limited utility, because it is unable to accurately describe how shape is evolving.

  20. Analysis of the slider force calibration procedure for the British Pendulum Skid Resistance Tester

    Science.gov (United States)

    Hiti, Miha; Ducman, Vilma

    2014-02-01

    British Pendulum Skid Resistance Testers are being used for the determination of the slip/skid resistance of surfaces by laboratories all around the world in different fields. The instrument itself can give reproducible results; however, the comparison of results obtained by different instruments can show large deviations. This paper presents a comparison of the performance of four pendulum testers, the investigation of requirements in international standards and the analysis of the calibration procedure for the determination of the slider force/deflection characteristics. The slider force/deflection characteristics were measured manually and also automatically with a uniaxial tensile/compression testing machine using different techniques. The results highlight the importance of the slider force/deflection characteristic shape and its influence on the results indicated by the pendulum tester and outline inconsistencies in different international standards describing the same device and its requirements. Presented results show good reproducibility and comparability of the pendulum test results when calibration is performed with the assembled pendulum either manually or automatically, provided the stricter slider force characteristic envelope requirements are taken into consideration. The actual slider force should be stable from 1.5 mm deflection onwards.

  1. Effects of alien plants on insect abundance and biomass: a food-web approach.

    Science.gov (United States)

    Heleno, Rúben H; Ceia, Ricardo S; Ramos, Jaime A; Memmott, Jane

    2009-04-01

    The replacement of native plants by alien species is likely to affect other trophic levels, particularly phytophagous insects. Nevertheless, the effect of alien plants on insect biomass has not yet been quantified. Given their critical role in transferring energy from plants to higher trophic levels, if alien plants do affect insect biomass, this could have far-reaching consequences for community structure. We used 35 food webs to evaluate the impacts of alien plants on insect productivity in a native forest in the Azores. Our food webs quantified plants, insect herbivores, and their parasitoids, which allowed us to test the effects of alien plants on species richness and evenness, insect abundance, insect biomass, and food-web structure. Species richness of plants and insects, along with plant species evenness, declined as the level of plant invasion increased. Nevertheless, none of the 4 quantitative food-web descriptors (number of links, link density, connectance, and interaction evenness) varied significantly with plant invasion independent of the size of the food web. Overall, insect abundance was not significantly affected by alien plants, but insect biomass was significantly reduced. This effect was due to the replacement of large insects on native plants with small insects on alien plants. Furthermore, the impact of alien plants was sufficiently severe to invert the otherwise expected pattern of species-richness decline with increased elevation. We predict a decrease in insect productivity by over 67% if conservation efforts fail to halt the invasion of alien plants in the Azores.

  2. Alien plant species list and distribution for Camdeboo National Park, Eastern Cape Province, South Africa

    Directory of Open Access Journals (Sweden)

    Mmoto L. Masubelele

    2009-09-01

    Full Text Available Protected areas globally are threatened by the potential negative impacts that invasive alien plants pose, and Camdeboo National Park (CNP, South Africa, is no exception. Alien plants have been recorded in the CNP since 1981, before it was proclaimed a national park by South African National Parks in 2005. This is the first publication of a list of alien plants in and around the CNP. Distribution maps of some of the first recorded alien plant species are also presented and discussed. To date, 39 species of alien plants have been recorded, of which 13 are invasive and one is a transformer weed. The majority of alien plant species in the park are herbaceous (39% and succulent (24% species. The most widespread alien plant species in the CNP are Atriplex inflata (= A. lindleyi subsp. inflata, Salsola tragus (= S. australis and cacti species, especially Opuntia ficus-indica. Eradication and control measures that have been used for specific problematic alien plant species are described. Conservation implications: This article represents the first step in managing invasive alien plants and includes the collation of a species list and basic information on their distribution in and around the protected area. This is important for enabling effective monitoring of both new introductions and the distribution of species already present. We present the first species list and distribution information for Camdeboo National Park.

  3. Policy alienation and work alienation: Two worlds apart?

    NARCIS (Netherlands)

    L.G. Tummers (Lars); S. van Thiel (Sandra); A.J. Steijn (Bram); V.J.J.M. Bekkers (Victor)

    2011-01-01

    textabstractThe notion of work alienation has been fascinating scholars and practitioners for a long time. In recent years, a related concept has been developed in the public administration discipline: policy alienation, which examines the alienation of public professionals from the policy they have

  4. Policy alienation and work alienation: Two worlds apart?

    NARCIS (Netherlands)

    L.G. Tummers (Lars); S. van Thiel (Sandra); A.J. Steijn (Bram); V.J.J.M. Bekkers (Victor)

    2011-01-01

    textabstractAbstract The notion of work alienation has been fascinating scholars and practitioners for a long time. In recent years, a related concept has been developed in the public administration discipline: policy alienation, which examines the alienation of public professionals from the policy

  5. 8 CFR 211.5 - Alien commuters.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent residence.... An alien commuter engaged in seasonal work will be presumed to have taken up residence in the United...

  6. Review of alien marine macrophytes in Tunisia

    Directory of Open Access Journals (Sweden)

    Y. R. SGHAIER

    2015-01-01

    Full Text Available In the present study, the list of alien marine macrophytes introduced into Tunisia was updated in the light of available data and new observations. A total of 27 alien marine macrophytes have been recorded so far from Tunisia: 18 Rhodophyta, 3 Ochrophyta, 5 Chlorophyta and 1 Magnoliophyta. For each species, the locality (-ies, the year (or period and the source of the first observation in Tunisia are given. The distribution and the status (casual, cryptogenic, established or questionable of species in Tunisia were evaluated and, where appropriate, discussed. Among them, Hypnea cornuta is reported for the first time from Tunisia. Fourteen alien marine macrophytes are established, whereas seven cryptogenic and two casual species require further investigation. Eleven species are considered as invasive or potentially invasive in the Mediterranean Sea: Acrothamnion preissii, Asparagopsis armata, A. taxiformis Indo-Pacific lineage, Hypnea cornuta, Lophocladia lallemandii, Womersleyella setacea, Caulerpa chemnitzia, C. cylindracea, C. taxifolia, Codium fragile subsp. fragile and Halophila stipulacea. Finally, the case of four questionable species is also discussed.

  7. Catalogue of alien animal species in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Hana Šefrová

    2005-01-01

    Full Text Available The catalogue of alien animal species registered in the Czech Republic, with data on their origin, date on the first observation, way of introduction (accidental, deliberate, spontaneous, invasive status (casual, non-invasive, post-invasive, invasive, habitat (eusynanthropic, urban, agricultural, natural, trophic requirements and possible influences (plant or stored-product pest, biodiversity influence. In total 595 species are listed, i.e. 1.8% of the fauna of this country; of these, 22 species of molluscs (8.8% of the local fauna, 451 spp. of arthropods (1.5%, 383 spp. of insects (1.4%, and 55 spp. of vertebrates (9.2%. Among the registered species, 248 spp. (41.8% are confined to closed and heated spaces by their occurrence, and 287 spp. have become naturalized (48.2%. Of these 113 spp. are considered invasive (19% of alien spp.. 65 spp. (10.9% of aliens are pests of stored products, 84 spp. (14.1% are parasites of important animals, 53 spp. (8.9% are pests of plants grown in heated rooms (above all, glasshouses, 28 ssp. (4.7% are agricultural or forest pests, and 39 spp. (6.6% may influence local biodiversity. The origin of the naturalized alien species is mostly in North America (70; 24.4%, the Mediterranean (61; 21.3%, E Asia (44; 15.4%, Central and SW Asia (43; 15%, and S or SE Asia (30; 10.5%.

  8. Global rise in emerging alien species results from increased accessibility of new source pools.

    Science.gov (United States)

    Seebens, Hanno; Blackburn, Tim M; Dyer, Ellie E; Genovesi, Piero; Hulme, Philip E; Jeschke, Jonathan M; Pagad, Shyama; Pyšek, Petr; van Kleunen, Mark; Winter, Marten; Ansong, Michael; Arianoutsou, Margarita; Bacher, Sven; Blasius, Bernd; Brockerhoff, Eckehard G; Brundu, Giuseppe; Capinha, César; Causton, Charlotte E; Celesti-Grapow, Laura; Dawson, Wayne; Dullinger, Stefan; Economo, Evan P; Fuentes, Nicol; Guénard, Benoit; Jäger, Heinke; Kartesz, John; Kenis, Marc; Kühn, Ingolf; Lenzner, Bernd; Liebhold, Andrew M; Mosena, Alexander; Moser, Dietmar; Nentwig, Wolfgang; Nishino, Misako; Pearman, David; Pergl, Jan; Rabitsch, Wolfgang; Rojas-Sandoval, Julissa; Roques, Alain; Rorke, Stephanie; Rossinelli, Silvia; Roy, Helen E; Scalera, Riccardo; Schindler, Stefan; Štajerová, Kateřina; Tokarska-Guzik, Barbara; Walker, Kevin; Ward, Darren F; Yamanaka, Takehiko; Essl, Franz

    2018-03-06

    Our ability to predict the identity of future invasive alien species is largely based upon knowledge of prior invasion history. Emerging alien species-those never encountered as aliens before-therefore pose a significant challenge to biosecurity interventions worldwide. Understanding their temporal trends, origins, and the drivers of their spread is pivotal to improving prevention and risk assessment tools. Here, we use a database of 45,984 first records of 16,019 established alien species to investigate the temporal dynamics of occurrences of emerging alien species worldwide. Even after many centuries of invasions the rate of emergence of new alien species is still high: One-quarter of first records during 2000-2005 were of species that had not been previously recorded anywhere as alien, though with large variation across taxa. Model results show that the high proportion of emerging alien species cannot be solely explained by increases in well-known drivers such as the amount of imported commodities from historically important source regions. Instead, these dynamics reflect the incorporation of new regions into the pool of potential alien species, likely as a consequence of expanding trade networks and environmental change. This process compensates for the depletion of the historically important source species pool through successive invasions. We estimate that 1-16% of all species on Earth, depending on the taxonomic group, qualify as potential alien species. These results suggest that there remains a high proportion of emerging alien species we have yet to encounter, with future impacts that are difficult to predict.

  9. Inventory of alien marine species of Cyprus (2009

    Directory of Open Access Journals (Sweden)

    S. KATSANEVAKIS

    2009-12-01

    Full Text Available An updated inventory of alien marine species from coastal and offshore waters of Cyprus is presented. Records were compiled based on the existing scientific and grey literature, including HCMR database of Mediterranean alien species, technical reports, scientific congresses, academic dissertations, and websites, as well as on unpublished/personal observations. The listed species were classified in one of five categories: established, invasive, casual, cryptogenic, and questionable. The mode of introduction and the year of first sighting were also reported for each species. Eight new records based on personal observations of the authors were reported (Chondria coerulescens, Neosiphonia sphaerocarpa, Enchelycore anatina, Lagocephalus spadiceus, Lagocephalus suezensis, Scomberomorus commerson, Sillago sihama, and Sphoeroides pachygaster. Nine species, previously reported as aliens in Cypriot waters, were excluded from the inventory for various reasons. Ten established species were characterized as invasive (Caulerpa racemosa var. cylindracea, Cerithium scabridum, Strombus persicus, Trochus erythraeus, Brachidontes pharaonis, Pinctada radiata, Fistularia commersonii, Lagocephalus sceleratus, Siganus luridus, and Siganus rivulatus as they have a substantial impact on biodiversity and/or local economy. The impact of alien marine species in Cyprus is expected to grow in the close future, and further effort directed towards recording alien invasions and their impact will be needed.

  10. The problematic of the geographical expansion of invasive alien species. Analysis and distribution of two species in the province of Avila and initiatives for the minimization of their effects; La problematica de la expansion geografica de las especies exoticas invasoras. Analisis y distribucion de dos especies en la provincia de Avila e iniciativas para la minimizacion de sus efectos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Quiroga, F.

    2012-07-01

    Invasive alien species currently constitute a serious threat for biodiversity and large economic losses. The risks associated to its introduction are in constant growth due to the increase of trade, tourism, transport and market globalization. Examples of these species can be found in the fauna such as the red swamp or Louisiana crawfish and in the flora as the ailanthus, which affect a great deal of the Spanish provinces, as that of Avila where they will be analyzed in greater detail. Because of it, the development of an effective action against its invasion through a series of measures, as well as the development and implementation of a legal framework, in addition to the information of the citizens are essential aspects for eradication or to mitigate its expansion. (Author)

  11. A Study of Static Performance of Fixed Inclined Slider Bearings – A ...

    African Journals Online (AJOL)

    In this paper, the performance of a fixed inclined slider bearing whose surfaces are lubricated by a non Newtonian power law lubricant is investigated numerically. Based on the power law model, the modified Reynolds equation is derived and solved using the finite element method. The effect of flow index on pressure ...

  12. A Study of Static Performance of Fixed Inclined Slider Bearings – A ...

    African Journals Online (AJOL)

    Michael Horsfall

    and friction. He compared numerical solutions for the bearing performance metrics with analytical solution using a range of bearing aspect ratios and power law indices. In this paper, we present the effect of power law fluids on the static performance characteristics of inclined slider bearings. Based on the power law model ...

  13. Bureaucracy and Alienation.

    Science.gov (United States)

    Hoy, Wayne K.; And Others

    1983-01-01

    Using surveys of the professional staffs of 41 secondary schools, this study examines the relationship between two aspects of bureaucratic structure (centralization and formalization) and two sorts of alienation (from work and expressive relations). It then compares the results with similar studies of social studies of social welfare agencies. (JW)

  14. Marine alien species as an aspect of global change

    Directory of Open Access Journals (Sweden)

    Anna Occhipinti-Ambrogi

    2010-06-01

    Full Text Available The transport of organisms across oceans is an anthropogenic agent of global change that has profoundly affected the natural distribution of littoral biota and altered the makeup of biogeographic regions. The homogenization of marine biotas is a phenomenon especially affecting coastal regions and is spearheaded by a suite of opportunistic species at the expense of native species. Climate change may exacerbate the trend: sea surface temperatures, hydrodynamics, pH and carbonate cycles, already show marked fluctuations compared to the past. Alien invasive species are impacted by the change of marine climate in a variety of ways, which are we have just begun to notice, observe and interpret. A conceptual framework has yet to be conceived that links theories on biological introductions and invasions with the physical aspects of global change. Therefore predicting the scale of invasions or their impact on biodiversity is a daunting task. Integration of biological and environmental information systems, niche models, and climate projections would improve management of aquatic ecosystems under the dual threats of biotic invasions and climate change. The recorded spread of alien species and analysis of patterns of invasions may serve as the starting point for searching connections with climate change descriptors. The Mediterranean Sea is home to an exceptionally large number of alien species, resulting from its exceptional history and multiple vectors. For much of the twentieth century alien thermophilic species, which had entered the Mediterranean through the Suez Canal, have been confined to the Levantine Basin. In recent years climate driven hydrographic changes have coincided with a pronounced expansion of alien thermophilic biota to the central and western basins of the Mediterranean. We discuss some changes in emergent functions and services in Mediterranean ecosystems under the combined effect of invasive species and climate changes.

  15. Forgetting and remembering alienation theory.

    Science.gov (United States)

    Yuill, Chris

    2011-01-01

    Alienation theory has acted as the stimulus for a great deal of research and writing in the history of sociology. It has formed the basis of many sociological "classics" focused on the workplace and the experiences of workers, and has also been mobilized to chart wider social malaise and individual troubles. Alienation theory usage has, however, declined significantly since its heyday of the 1960s and 1970s. Here, the reasons why alienation theory was "forgotten" and what can be gained by "remembering" alienation theory are explored. to realize this ambition this article proceeds by (1) briefly visiting differing definitions of alienation theory, before charting its high point, and the various debates and tensions of the time, during the 1960s and 1970s; (2) analysing the reasons why alienation theory fell from grace from the 1980s onwards; (3) elaborating how and why alienation theory is still relevant for sociology and the wider social sciences today.

  16. Alien flora of Turkey: checklist, taxonomic composition and ecological attributes

    Czech Academy of Sciences Publication Activity Database

    Uludag, A.; Aksoy, N.; Yazlik, A.; Arslan, Z. F.; Yazmiş, E.; Üremiş, I.; Cossu, T. A.; Groom, Q.; Pergl, Jan; Pyšek, Petr; Brundu, G.

    2017-01-01

    Roč. 35, č. 1 (2017), s. 61-85 ISSN 1619-0033 Grant - others:COST(XE) TD1209; AV ČR(CZ) AP1002 Program:FA; Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : alien flora * Turkey * invasions Subject RIV: EF - Botanics OBOR OECD: Biodiversity conservation

  17. Alien fish species in upper Sakarya River and their distribution ...

    African Journals Online (AJOL)

    However, the fact that the flood plains have been reclaimed, excessive hunting, destruction of the ecologic balance and invasion of the area by the alien fish species threatens the fish stocks in Sakarya River. In this study, we aimed to determine the dispersion area of Carassius gibelio (Bloch, 1782), Oreochromis niloticus ...

  18. Two decades of fighting aliens: exploring Working for Water successes

    CSIR Research Space (South Africa)

    Ntshotsho, P

    2015-10-01

    Full Text Available and human well-being. Through its Working for Water programme, the Department of Environmental Affairs is tackling the problem head-on. The programme was specifically set up in 1995 to manage invasive alien plants and provide employment to marginalised...

  19. Alien species pathways to the Galapagos Islands, Ecuador.

    Directory of Open Access Journals (Sweden)

    M Verónica Toral-Granda

    Full Text Available Alien species, one of the biggest threats to natural ecosystems worldwide, are of particular concern for oceanic archipelagos such as Galápagos. To enable more effective management of alien species, we reviewed, collated and analysed all available records of alien species for Galápagos. We also assembled a comprehensive dataset on pathways to and among the Galápagos Islands, including tourist and resident numbers, tourist vessels, their itineraries and visitation sites, aircraft capacity and occupancy, air and sea cargo and biosecurity interceptions. So far, 1,579 alien terrestrial and marine species have been introduced to Galápagos by humans. Of these, 1,476 have become established. Almost half of these were intentional introductions, mostly of plants. Most unintentional introductions arrived on plants and plant associated material, followed by transport vehicles, and commodities (in particular fruit and vegetables. The number, frequency and geographic origin of pathways for the arrival and dispersal of alien species to and within Galápagos have increased over time, tracking closely the increase in human population (residents and tourists on the islands. Intentional introductions of alien species should decline as biosecurity is strengthened but there is a danger that unintentional introductions will increase further as tourism on Galápagos expands. This unique world heritage site will only retain its biodiversity values if the pathways for invasion are managed effectively.

  20. Alien species pathways to the Galapagos Islands, Ecuador

    Science.gov (United States)

    Trueman, Mandy; Izurieta, Juan Carlos; Araujo, Eddy; Cruz, Marilyn; Zander, Kerstin K.; Izurieta, Arturo

    2017-01-01

    Alien species, one of the biggest threats to natural ecosystems worldwide, are of particular concern for oceanic archipelagos such as Galápagos. To enable more effective management of alien species, we reviewed, collated and analysed all available records of alien species for Galápagos. We also assembled a comprehensive dataset on pathways to and among the Galápagos Islands, including tourist and resident numbers, tourist vessels, their itineraries and visitation sites, aircraft capacity and occupancy, air and sea cargo and biosecurity interceptions. So far, 1,579 alien terrestrial and marine species have been introduced to Galápagos by humans. Of these, 1,476 have become established. Almost half of these were intentional introductions, mostly of plants. Most unintentional introductions arrived on plants and plant associated material, followed by transport vehicles, and commodities (in particular fruit and vegetables). The number, frequency and geographic origin of pathways for the arrival and dispersal of alien species to and within Galápagos have increased over time, tracking closely the increase in human population (residents and tourists) on the islands. Intentional introductions of alien species should decline as biosecurity is strengthened but there is a danger that unintentional introductions will increase further as tourism on Galápagos expands. This unique world heritage site will only retain its biodiversity values if the pathways for invasion are managed effectively. PMID:28902860

  1. Alien species pathways to the Galapagos Islands, Ecuador.

    Science.gov (United States)

    Toral-Granda, M Verónica; Causton, Charlotte E; Jäger, Heinke; Trueman, Mandy; Izurieta, Juan Carlos; Araujo, Eddy; Cruz, Marilyn; Zander, Kerstin K; Izurieta, Arturo; Garnett, Stephen T

    2017-01-01

    Alien species, one of the biggest threats to natural ecosystems worldwide, are of particular concern for oceanic archipelagos such as Galápagos. To enable more effective management of alien species, we reviewed, collated and analysed all available records of alien species for Galápagos. We also assembled a comprehensive dataset on pathways to and among the Galápagos Islands, including tourist and resident numbers, tourist vessels, their itineraries and visitation sites, aircraft capacity and occupancy, air and sea cargo and biosecurity interceptions. So far, 1,579 alien terrestrial and marine species have been introduced to Galápagos by humans. Of these, 1,476 have become established. Almost half of these were intentional introductions, mostly of plants. Most unintentional introductions arrived on plants and plant associated material, followed by transport vehicles, and commodities (in particular fruit and vegetables). The number, frequency and geographic origin of pathways for the arrival and dispersal of alien species to and within Galápagos have increased over time, tracking closely the increase in human population (residents and tourists) on the islands. Intentional introductions of alien species should decline as biosecurity is strengthened but there is a danger that unintentional introductions will increase further as tourism on Galápagos expands. This unique world heritage site will only retain its biodiversity values if the pathways for invasion are managed effectively.

  2. Alien plant dynamics following fire in mediterranean-climate California shrublands

    Science.gov (United States)

    Keeley, J.E.; Baer-Keeley, M.; Fotheringham, C.J.

    2005-01-01

    Over 75 species of alien plants were recorded during the first five years after fire in southern California shrublands, most of which were European annuals. Both cover and richness of aliens varied between years and plant association. Alien cover was lowest in the first postfire year in all plant associations and remained low during succession in chaparral but increased in sage scrub. Alien cover and richness were significantly correlated with year (time since disturbance) and with precipitation in both coastal and interior sage scrub associations. Hypothesized factors determining alien dominance were tested with structural equation modeling. Models that included nitrogen deposition and distance from the coast were not significant, but with those variables removed we obtained a significant model that gave an R2 = 0.60 for the response variable of fifth year alien dominance. Factors directly affecting alien dominance were (1) woody canopy closure and (2) alien seed banks. Significant indirect effects were (3) fire intensity, (4) fire history, (5) prefire stand structure, (6) aridity, and (7) community type. According to this model the most critical factor influencing aliens is the rapid return of the shrub and subshrub canopy. Thus, in these communities a single functional type (woody plants) appears to the most critical element controlling alien invasion and persistence. Fire history is an important indirect factor because it affects both prefire stand structure and postfire alien seed banks. Despite being fire-prone ecosystems, these shrublands are not adapted to fire per se, but rather to a particular fire regime. Alterations in the fire regime produce a very different selective environment, and high fire frequency changes the selective regime to favor aliens. This study does not support the widely held belief that prescription burning is a viable management practice for controlling alien species on semiarid landscapes. ?? 2005 by the Ecological Society of

  3. 22 CFR 41.71 - Transit aliens.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Transit aliens. 41.71 Section 41.71 Foreign... NATIONALITY ACT, AS AMENDED Transit Aliens § 41.71 Transit aliens. (a) Transit aliens—general. An alien is classifiable as a nonimmigrant transit alien under INA 101(a) (15) (C) if the consular officer is satisfied...

  4. 28 CFR 21.3 - Aliens.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Aliens. 21.3 Section 21.3 Judicial Administration DEPARTMENT OF JUSTICE WITNESS FEES § 21.3 Aliens. (a) Aliens entitled to payment of $30 per day. The following aliens are entitled to witness fees and allowances provided in § 21.4: (1) Aliens...

  5. 8 CFR 1244.4 - Ineligible aliens.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An alien...

  6. 8 CFR 244.4 - Ineligible aliens.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for Temporary...

  7. 8 CFR 236.13 - Ineligible aliens.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Ineligible aliens. 236.13 Section 236.13 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL OF ALIENS ORDERED REMOVED Family Unity Program § 236...

  8. 8 CFR 232.3 - Arriving aliens.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Arriving aliens. 232.3 Section 232.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS DETENTION OF ALIENS FOR PHYSICAL AND MENTAL EXAMINATION § 232.3 Arriving aliens. When a district director has reasonable grounds...

  9. Captured by Aliens

    Science.gov (United States)

    Achenbach, Joel

    2000-03-01

    Captured by Aliens is a long and twisted voyage from science to the supernatural and back again. I hung out in Roswell, N.M., spent time with the Mars Society, met a guy who was figuring out the best way to build a spaceship to go to Alpha Centauri. I visited the set of the X-Files and talked to Mulder and Scully. One day over breakfast I was told by NASA administrator Dan Goldin, We live in a fog, man! He wants the big answers to the big questions. I spent a night in the base of a huge radio telescope in the boondocks of West Virginia, awaiting the signal from the aliens. I was hypnotized in a hotel room by someone who suspected that I'd been abducted by aliens and that this had triggered my interest in the topic. In the last months of his life, I talked to Carl Sagan, who believed that the galaxy riots with intelligent civilizations. He's my hero, for his steadfast adherence to the scientific method. What I found in all this is that the big question that needs immediate attention is not what's out THERE, but what's going on HERE, on Earth, and why we think the way we do, and how we came to be here in the first place.

  10. Digestive efficiency of indigenous and invasive avian species fed ...

    African Journals Online (AJOL)

    ... Knysna (Tauraco corythaix) and Purple-crested (Gallirex porphyreolophus) Turacos and invasive alien Rose-ringed Parakeets (Psittacula krameri) met their energy demands when fed fruits of four fleshyfruited invasive alien plant species: Solanum mauritianum, Cinnamomum camphora, Psidium guajava and Morus alba.

  11. The legitimacy of alien rulers

    DEFF Research Database (Denmark)

    Horne, Christine; Ben-Nun Bloom, Pazit; Irwin, Kyle

    2016-01-01

    In the modern world, alien rulers are generally perceived to lack legitimacy. Political legitimacy is important because it is thought to be the principal alternative to coercive institutions. Little empirical evidence supports these claims, however. We devise a laboratory experiment that isolates...... alienness from other ruler characteristics. The experiment tests whether alien rulers have less legitimacy than native rulers, and whether the ability to punish compensates for this disadvantage. Using American and Israeli college student samples, we find that alien rulers receive less compliance than...

  12. Application Value of Slider-Crank Mechanism in Pick-and-Place Operation of Delta Robot

    Directory of Open Access Journals (Sweden)

    Zhe QIN

    2018-01-01

    Full Text Available By absorbing the advantages of the rotary-driven Delta robot and linear-driven Delta robot, a Delta robot for pick-and-place operation that forms a crank-slider at the drive joint is designed.To take the most common gate shaped curve in Cartesian space as the motion trail of robotic pick-and-place operation, according to the kinematics inverse solution theory of Delta robot, this thesis mainly solves the output angular velocity of robot-driven joint. Establishing the static transfer mathematical model and solving the forced condition of driving joint. The simulation analysis show that after the upper slider-crank mechanism is connected to the driving joint, the angular velocity of the driving joint changes suddenly, which caused a rigid impact on the robot in the picking and releasing operation, though the force of the driving joint can be made smaller.

  13. Optimal design of planar slider-crank mechanism using teaching-learning-based optimization algorithm

    International Nuclear Information System (INIS)

    Chaudhary, Kailash; Chaudhary, Himanshu

    2015-01-01

    In this paper, a two stage optimization technique is presented for optimum design of planar slider-crank mechanism. The slider crank mechanism needs to be dynamically balanced to reduce vibrations and noise in the engine and to improve the vehicle performance. For dynamic balancing, minimization of the shaking force and the shaking moment is achieved by finding optimum mass distribution of crank and connecting rod using the equipemental system of point-masses in the first stage of the optimization. In the second stage, their shapes are synthesized systematically by closed parametric curve, i.e., cubic B-spline curve corresponding to the optimum inertial parameters found in the first stage. The multi-objective optimization problem to minimize both the shaking force and the shaking moment is solved using Teaching-learning-based optimization algorithm (TLBO) and its computational performance is compared with Genetic algorithm (GA).

  14. Earthquake statistics in a Block Slider Model and a fully dynamic Fault Model

    Directory of Open Access Journals (Sweden)

    D. Weatherley

    2004-01-01

    Full Text Available We examine the event statistics obtained from two differing simplified models for earthquake faults. The first model is a reproduction of the Block-Slider model of Carlson et al. (1991, a model often employed in seismicity studies. The second model is an elastodynamic fault model based upon the Lattice Solid Model (LSM of Mora and Place (1994. We performed simulations in which the fault length was varied in each model and generated synthetic catalogs of event sizes and times. From these catalogs, we constructed interval event size distributions and inter-event time distributions. The larger, localised events in the Block-Slider model displayed the same scaling behaviour as events in the LSM however the distribution of inter-event times was markedly different. The analysis of both event size and inter-event time statistics is an effective method for comparative studies of differing simplified models for earthquake faults.

  15. Desain dan Optimasi Injection Mold Sistem Slider pada Produk Stick T15

    Directory of Open Access Journals (Sweden)

    Lutfi Khoirul Miftakhul Ni'am

    2017-12-01

    Full Text Available The design of injection molding is the initial process to produce a large-scale product of plastic material which heated and injected into the mold. Design of the preform mold using the plastic material polyethylene terephthalate with the construction of the slider, so that the products which was made have undercut and can’t be made in the core section and cavity. The purpose of this design is to design the slider on the product preform. The software which used for this design using CATIA V5R19 and simulation software production using Autodesk Moldflow Insight 2016. The step on designing a unit injection mold in the preform includes several steps. The first step is identify the product, the calculation of the cooling and input the data calculation result to an moldflow. The second step is design construction slider and determine the mold material as well as calculating the construction mold. The third step is pour the results of the design in figure 2D. Based on the analysis results from moldflow obtained cooling optimal.i.e. the type of cooling series type 2, and if can be concluded construction of the mold said to be safe if the stress, the style and the determination  of material which occurs under the stress and style of permit.

  16. Morphology and conservation of the mesoamerican slider (Trachemys venusta, Emydidae) from the Atrato River Basin, Colombia

    International Nuclear Information System (INIS)

    Ceballos, Claudia P; Brand, William A

    2014-01-01

    The phylogenetic relationships of the mesoamerican slider, Trachemys venusta that inhabits the Atrato River Basin of Colombia have been controversial as three different names have been proposed during the last 12 years: T. v. venusta, T. v. uhrigi, and T. ornate venusta. Using a group of sliders that was confiscated by the regional authority we compared the morphology of T venusta distributed in the Atrato River with the morphology of the subspecies putatively distributed in Colombia. We found that the Colombian mesoamerican slider has an overall smaller size, different plastral inter-scute seam formula, and different head, carapace and plastron coloration patterns. In addition, we also report the poor health condition of these individuals that have endured this illegal trade. We underscore an urgent need for further studies of individuals indigenous to Colombia to better understand the phylogenetic relationships of T. venusta throughout its distributional range, along with a more effective control of the illegal turtle trade in the Uraba Region of Colombia.

  17. SLIDER: a generic metaheuristic for the discovery of correlated motifs in protein-protein interaction networks.

    Science.gov (United States)

    Boyen, Peter; Van Dyck, Dries; Neven, Frank; van Ham, Roeland C H J; van Dijk, Aalt D J

    2011-01-01

    Correlated motif mining (cmm) is the problem of finding overrepresented pairs of patterns, called motifs, in sequences of interacting proteins. Algorithmic solutions for cmm thereby provide a computational method for predicting binding sites for protein interaction. In this paper, we adopt a motif-driven approach where the support of candidate motif pairs is evaluated in the network. We experimentally establish the superiority of the Chi-square-based support measure over other support measures. Furthermore, we obtain that cmm is an np-hard problem for a large class of support measures (including Chi-square) and reformulate the search for correlated motifs as a combinatorial optimization problem. We then present the generic metaheuristic slider which uses steepest ascent with a neighborhood function based on sliding motifs and employs the Chi-square-based support measure. We show that slider outperforms existing motif-driven cmm methods and scales to large protein-protein interaction networks. The slider-implementation and the data used in the experiments are available on http://bioinformatics.uhasselt.be.

  18. Evaluation of rebound tonometry in red-eared slider turtles (Trachemys scripta elegans).

    Science.gov (United States)

    Delgado, Cherlene; Mans, Christoph; McLellan, Gillian J; Bentley, Ellison; Sladky, Kurt K; Miller, Paul E

    2014-07-01

    To evaluate feasibility and accuracy of intraocular pressure (IOP) measurement by rebound tonometry in adult red-eared slider turtles and determine the effects of manual and chemical restraint on IOP. Seventeen adult red-eared slider turtles. Intraocular pressure was measured with TonoLab® and TonoVet® tonometers in conscious, unrestrained turtles. To evaluate the effects of manual restraint, turtles were restrained by digital pressure on the rostral head or proximal neck. The effect of two chemical restraint protocols (dexmedetomidine, ketamine, midazolam [DKM] and dexmedetomidine, ketamine [DK] subcutaneously) on IOP was evaluated. Triplicate TonoLab® and TonoVet® readings were compared with direct manometry in three ex vivo turtle eyes. TonoLab® correlated better with manometry at IOPs turtles was significantly lower (P turtles. Chemical and manual neck restraint affected IOP. Rostral head restraint had no significant effect on IOP and is, therefore, recommended as the appropriate restraint technique in red-eared slider turtles. TonoLab® measurements estimated actual IOP more accurately, within physiologic range, than measurements obtained using the TonoVet®. © 2013 American College of Veterinary Ophthalmologists.

  19. Exploring critical uncertainties in pathway assessments of human-assisted introductions of alien forest species in Canada

    Science.gov (United States)

    Denys Yemshanov; Frank H. Koch; Mark J. Ducey; Marty Siltanen; Kirsty Wilson; Klaus Koehler

    2013-01-01

    Long-distance introductions of alien species are often driven by socioeconomic factors, such that conventional “biological” invasion models may not be capable of estimating spread fully and reliably. In this study, we demonstrate a new technique for assessing and reconstructing human-mediated pathways of alien forest species entries to major settlements in Canada via...

  20. Brechtian Alienation in Videogames

    Directory of Open Access Journals (Sweden)

    Daniel Joseph Dunne

    2014-11-01

    Full Text Available Immersion is constantly being broken in video games via the intrusion of mechanics and features that cause no end of distraction, breaking the player’s engagement in both the game’s narrative and in the gameplay. Yet these breaks are an integral part of games, whether through loading, saving or any other mechanical system that detracts from the playing the core game. These aren’t analysed as thoroughly as they could be in current game academia. However Bertolt Brecht’s “Verfremdungseffekt”, or distancing effect, provides a much needed foundation in the analysis of these sections within games that provoke a feeling of alienation.

  1. Bark beetles and pinhole borers (Curculionidae, Scolytinae, Platypodinae alien to Europe

    Directory of Open Access Journals (Sweden)

    Lawrence Kirkendall

    2010-09-01

    Full Text Available Invasive bark beetles are posing a major threat to forest resources around the world. DAISIE’s web-based and printed databases of invasive species in Europe provide an incomplete and misleading picture of the alien scolytines and platypodines. We present a review of the alien bark beetle fauna of Europe based on primary literature through 2009. We find that there are 18 Scolytinae and one Platypodinae species apparently established in Europe, from 14 different genera. Seventeen species are naturalized. We argue that Trypodendron laeve, commonly considered alien in Europe, is a native species; conversely, we hypothesize that Xyleborus pfeilii, which has always been treated as indigenous, is an alien species from Asia. We also point out the possibility that the Asian larch bark beetle Ips subelongatus is established in European Russia. We show that there has been a marked acceleration in the rate of new introductions to Europe, as is also happening in North America: seven alien species were first recorded in the last decade. We present information on the biology, origins, and distributions of the alien species. All but four are polyphagous, and 11 are inbreeders: two traits which increase invasiveness. Eleven species are native to Asia, six to the Americas, and one is from the Canary Islands. The Mediterranean is especially favorable for invasives, hosting a large proportion of the aliens (8/18. Italy, Spain and France have the largest numbers of alien species (15, 10 and 7 respectively. We point out that the low numbers for at least some countries is likely due to under-reporting. Finally, we discuss the difficulties associated with identifying newly invasive species. Lack of good illustrations and keys hinder identification, particularly for species coming from Asia and Oceania.

  2. Impacts of invading alien plant species on water flows at stand and catchment scales

    CSIR Research Space (South Africa)

    Le Maitre, David C

    2015-05-01

    Full Text Available There have been many studies of the diverse impacts of invasions by alien plants but few have assessed impacts on water resources. We reviewed the information on the impacts of invasions on surface runoff and groundwater resources at stand...

  3. Functional differences between native and alien species : a global-scale comparison

    NARCIS (Netherlands)

    Ordonez, Alejandro; Wright, Ian J.; Olff, Han; Kitajima, Kaoru

    2010-01-01

    1. A prevalent question in the study of plant invasions has been whether or not invasions can be explained on the basis of traits. Despite many attempts, a synthetic view of multi-trait differences between alien and native species is not yet available. 2. We compiled a database of three ecologically

  4. Poles Apart: Comparing Trends of Alien Hymenoptera in New Zealand with Europe (DAISIE.

    Directory of Open Access Journals (Sweden)

    Darren Ward

    Full Text Available Developing generalisations of invasive species is an important part of invasion biology. However, trends and generalisations from one part of the world may not necessarily hold elsewhere. We present the first inventory and analysis of all Hymenoptera alien to New Zealand, and compare patterns from New Zealand with those previously published from Europe (DAISIE. Between the two regions there was broad correlation between families with the highest number of alien species (Braconidae, Encyrtidae, Pteromalidae, Eulophidae, Formicidae, Aphelinidae. However, major differences also existed. The number of species alien to New Zealand is higher than for Europe (334 vs 286, and major differences include: i the much lower proportion of intentionally released species in New Zealand (21% vs 63% in Europe; and ii the greater proportion of unintentionally introduced parasitoids in New Zealand (71.2% vs 22.6%. The disharmonic 'island' nature of New Zealand is shown, as a high proportion of families (36% have no native representatives, and alien species also represent >10% of the native fauna for many other families. A much larger proportion of alien species are found in urban areas in New Zealand (60% compared to Europe (~30%, and higher numbers of alien species were present earlier in New Zealand (especially <1950. Differences in the origins of alien species were also apparent. Unlike Europe, the New Zealand data reveals a change in the origins of alien species over time, with an increasing dominance of alien species from Australasia (a regional neighbour during the past 25 years. We recommend that further effort be made towards the formation, and analysis, of regional inventories of alien species. This will allow a wider range of taxa and regions to be examined for generalisations, and help assess and prioritise the risk posed by certain taxa towards the economy or environment.

  5. 8 CFR 245a.32 - Ineligible aliens.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Ineligible aliens. 245a.32 Section 245a.32 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS ADJUSTMENT OF STATUS TO... IMMIGRATION AND NATIONALITY ACT LIFE Act Amendments Family Unity Provisions § 245a.32 Ineligible aliens. The...

  6. Unveiling the status of alien animals in the arid zone of Asia

    Directory of Open Access Journals (Sweden)

    Lyubing Zhang

    2016-01-01

    Full Text Available Biological invasion is one of the most threatening factors for biodiversity conservation. Lacking information on alien species in certain regions of the world hampers a balanced understanding of invasion processes and efficient data exchange among stakeholders. Current knowledge gaps are in need of urgent concern. We therefore conducted a review on alien animals in Xinjiang, an unknown region of invasion ecology. Xinjiang lies in the heartland of the Asian continent, covering an area of 1,664,900 km2. In the past 64 years, 128 alien animal species were recorded in this region, 39% of which became invasive and led to loss of native biodiversity. Most of these species were introduced through diversification of local agriculture and aquaculture. This process was aggravated by improving transportation and flourishing trade. Multiple linear regression models and correlation analysis were run for explaining influence of environmental and anthropogenic factors on status of alien animals: economically developed areas with abundant water resource, oases in particular, were prone to be hotspots of alien animal species in this arid and semi-arid region. This study also revealed that taxonomically biased and lagged research were critical problems that impeded studies on biological invasions in Xinjiang, and proposed feasible solutions.

  7. Melanin deposition ruled out as cause of color changes in the red-eared sliders (Trachemys scripta elegans).

    Science.gov (United States)

    Cao, Dainan; Gong, Shiping; Yang, Jiangbo; Li, Weiye; Ge, Yan; Wei, Yufeng

    2018-03-01

    Animal coloration primarily depends on the presence of pigments and the mixing ratio of eumelanin and pheomelanin. The color of red-eared slider's carapace varies with age, from an olive green to a yellow green, and then to a yellow brown in juveniles, generally. The purpose of the present study was to investigate whether this color change is related to the difference in melanin expression. Melanin deposition levels were examined in the carapace, skin, eye and muscle of the three color-types using hematoxylin and eosin staining. Moreover, the full-length coding sequence (CDS) of red-eared slider turtle melanin biosynthesis regulatory genes TYR, TYRP1, MITF and SLC24A5 were cloned, sequenced and quantitatively analyzed. Both histological view of melanin deposition and quantitative real-time PCR test of melanin-regulated gene expressions showed that there are significant differences among different tissues of red-eared slider, but no significant difference among different color-types, indicating that melanin deposition is not associated with ontogenetic color change in the carapace of red-eared slider. This study initially explore the melanin deposition and the mRNA expression of melanin biosynthesis regulatory genes in red-eared slider, which serve as a foundation for further insight into the pigmentation patterns and the mechanism of body color change in turtles. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. The role of alienation in mental hospitalization.

    Science.gov (United States)

    McDowell, D J; Miller, I W; Magaro, P A

    1977-01-01

    A scale that assesses alienation was constructed from seven previously reported scales and administered to 74 psychiatric inpatients for whom behavioral and demographic data also were compiled. Factor analysis of alienation items yielded no major factors, which suggests that the construct is not unitary. A rotated factor matrix of alienation scores and behavioral and demographic variables showed that alienation does not account for a major proportion of variance in life history variables or current interpersonal functioning. Regression analysis indicated that alienation scores were predicted poorly from other variables. Moreover, alienation scores were poor predictors of length of hospitalization, which indicates that alienation has little power to account for relative severity of deviance.

  9. The zone of alienation

    International Nuclear Information System (INIS)

    Nagorski, A.

    1996-01-01

    Ten years after the nuclear disaster, people still live and die in Chernobyl. Thousands of people continue to live and work there. Roughly 500 have moved back into their old homes inside the alienation zone. Fewer than half still alive. Medical researchers in the area insist that immune systems are weakened by doses of radiation far lower than previously thought. However, an European Union sponsored study concluded that Chernobyl's toll has been exaggerated. Thus, while 760 children in the contaminated area have developed thyroid cancer, only three have died as a result. Yet in and around Chernobyl, people carry on their lives and the Ukrainian Government says it can't afford to close the plant without billions of dollars in Western aid. ills

  10. Effect of Magnetohydrodynamic Couple Stresses on Dynamic Characteristics of Exponential Slider Bearing

    Directory of Open Access Journals (Sweden)

    N.B. Naduvinamani

    2017-05-01

    Full Text Available The effect of couple stresses on static and dynamic characteristics of exponential slider bearing in the presence of magnetic field considering squeeze action is theoretically analyzed in this paper. The modified magnetohydrodynamic couple stress Reynolds type equation is derived on the basis of Stokes couple stress model and closed form expressions are obtained for static and dynamic character coefficients. Comparing with bearing lubricated with non-conducting Newtonian lubricants, the magnetohydrodynamic couple stress lubrication provides the higher steady load carrying capacity, dynamic stiffness and damping coefficient. The exponential bearing shows higher efficiency for small film thickness at higher value of couple stress parameter and Hartmann number.

  11. Dynamic Performance Characteristics of a Curved Slider Bearing Operating with Ferrofluids

    Directory of Open Access Journals (Sweden)

    Udaya P. Singh

    2012-01-01

    Full Text Available In the present theoretical investigation, the effect of ferrofluid on the dynamic characteristics of curved slider bearings is presented using Shliomis model which accounts for the rotation of magnetic particles, their magnetic moments, and the volume concentration in the fluid. The modified Reynolds equation for the dynamic state of the bearing is obtained. The results of dynamic stiffness and damping characteristics are presented. It is observed that the effect of rotation of magnetic particles improves the stiffness and damping capacities of the bearings.

  12. Prosopis, an Alien among the Sacred Trees of South India

    OpenAIRE

    Walter, Kurt

    2011-01-01

    The problematic of invasive species in an alien environment has aroused the attention of scientists all over the world for quite some time. One of the exotic tree species that has provoked special attention in the tropical drylands is Prosopis juliflora. Originating in South America, prosopis (hereafter referred to as prosopis) has been introduced in the hot and semi-arid zones of the world particularly to provide fuelwood, to stabilize sand dunes and to combat desertification. The tree has b...

  13. Invasion of a mined landscape: what habitat characteristics are influencing the occurrence of invasive plants?

    Science.gov (United States)

    D. Lemke; I.A. Tazisong; Y. Wang; J.A. Brown

    2012-01-01

    Throughout the world, the invasion of alien plants is an increasing threat to native biodiversity. Invasion is especially prevalent in areas affected by land transformation and anthropogenic disturbance. Surface mines are a major disturbance, and thus may promote the establishment and expansion of invasive plant communities. Environmental and habitat factors that may...

  14. Geographical Constraints Are Stronger than Invasion Patterns for European Urban Floras

    OpenAIRE

    Ricotta, Carlo; Celesti-Grapow, Laura; Kühn, Ingolf; Rapson, Gillian; Pyšek, Petr; La Sorte, Frank A.; Thompson, Ken

    2014-01-01

    Understanding the mechanisms that affect invasion success of alien species is an important prerequisite for the effective management of present and future aliens. To gain insight into this matter we asked the following questions: Are the geographical patterns of species distributions in urban floras different for native compared with alien plant species? Does the introduction of alien species contribute to the homogenization of urban floras? We used a Mantel test on Jaccard dissimilarity matr...

  15. Are the ecological impacts of alien species misrepresented? A review of the “native good, alien bad” philosophy

    OpenAIRE

    Goodenough, Anne E

    2010-01-01

    The study of invasion ecology usually focuses on the negative impacts of alien species, while potential positive impacts are often overlooked. Understanding of biotic interactions may thus be skewed towards the negative, which could have important implications for ecological management and conservation. This article provides a comprehensive review of all types of impacts, both beneficial and detrimental, that can result from species translocation. An extensive review of literature on species ...

  16. Alien species in different habitat types of Slovenia: analysis of vegetation database

    OpenAIRE

    Küzmič, Filip; Šilc, Urban

    2017-01-01

    Background and purpose: Invasion by alien plant species is considered as one of major threats to biodiversity. Actual invasion of different habitats in particular country is important for understanding processes that are important in invasion ecology as well as for the nature conservation.Materials and methods: Vegetation relevés stored in a database Vegetation of Slovenia were translated into 30 EUNIS habitat types which enables comparison with similar studies in other European countries. Ou...

  17. Do local enemies attack alien and native Impatiens alike?

    Directory of Open Access Journals (Sweden)

    Kamil Najberek

    2017-12-01

    Full Text Available The enemy release hypothesis (ERH attributes the invasive behavior of some alien species to decreased pressure from natural enemies, as they have been left behind in the hosts’ native range. The majority of research supports this idea, but some studies confirm it only partially or even contradict it. Here, we present the results of ERH tests of three Impatiens species studied in southern Poland in 2010–2011. Two of them are alien and invasive in Europe (Impatiens glandulifera, I. parviflora and one is native (I. noli-tangere. We compared the three species in terms of the percentage of all leaves showing symptoms of disease and/or damage, and also the number of pests recorded on the monitored plants. In 1071 individual plant controls, we assessed 17 180 leaves, 7552 of which showed symptoms of disease/damage, and we recorded 5721 invertebrates, 5220 of them were pests. Rusts and spots were the predominant symptoms and Aphidoidea were the dominant group of pests. Comparisons of the two alien and one native Impatiens did not confirm the ERH in 90% of the performed tests. Most of the differences between the species were not significant, and most of the significant ones contradicted the ERH. The only results confirming the ERH were found in comparisons between I. parviflora and I. noli-tangere. The tests between two alien species showed that I. parviflora was under higher pest pressure, while I. glandulifera had more disease and damage symptoms, thus, plant–enemy relations differed between the two balsams. In summary, the presented results add evidence that the success of some alien species may depend on factors related to biotic and/or abiotic conditions in ways that are not explained by the enemy release hypothesis.

  18. Implementing the European policies for alien species – networking, science, and partnership in a complex environment

    Directory of Open Access Journals (Sweden)

    Stelios Katsanevakis

    2013-02-01

    Full Text Available The European Commission has recognized the need for more stringent action to manage biological invasions and has committed to develop adedicated legislative instrument. Under this upcoming legislation, European countries and their relevant institutions will have additional obligations and commitments in respect to invasive alien species. In September 2012, the European Commission’s Joint Research Centre (JRC launched the European Alien Species Information Network (EASIN to facilitate the exploration of existing alien species information from distributed sources and to assist the implementation of European policies on biological invasions. Subsequent to the launching of EASIN, there was an evident need to define its niche within a complex environment of global, European, regional and national information systems. Herein we propose an organizational chart clearly defining the role of each actor in this framework, and we emphasize the need for collaboration in order to effectively support EU policies.

  19. A Generic Friction Model for Radial Slider Bearing Simulation Considering Elastic and Plastic Deformation

    Directory of Open Access Journals (Sweden)

    Günter Offner

    2015-06-01

    Full Text Available The investigation of component dynamics is one of the main tasks of internal combustion engine (ICE simulation. This prediction is important in order to understand complex loading conditions, which happen in a running ICE. Due to the need for fuel saving, mechanical friction, in particular in radial slider bearings, is one important investigation target. A generic friction modeling approach for radial slider bearings, which can be applied to lubricated contact regimes, will be presented in this paper. Besides viscous friction, the approach considers in particular boundary friction. The parameterization of the friction model is done using surface material and surface roughness measurement data. Furthermore, fluid properties depending on the applied oil additives are being considered. The application of the model will be demonstrated for a typical engineering task of a connecting rod big end study to outline the effects of contact surface texture. AlSn-based and polymer coated bearing shells will be analyzed and compared with respect to friction reduction effects, running-in behavior and thermal load capabilities.

  20. Ancient aliens on mars

    CERN Document Server

    Bara, Mike

    2013-01-01

    Best-selling author and Secret Space Program researcher Bara brings us this lavishly illustrated volume on alien structures on Mars. Was there once a vast, technologically advanced civilization on Mars, and did it leave evidence of its existence behind for humans to find eons later? Did these advanced extraterrestrial visitors vanish in a solar system wide cataclysm of their own making, only to make their way to Earth and start anew? Was Mars once as lush and green as the Earth, and teeming with life? Did Mars once orbit a missing member of the solar system, a "Super Earth” that vanished in a disaster that devastated life on Earth and Venus and left us only the asteroid belt as evidence of its once grand existence? Did the survivors of this catastrophe leave monuments and temples behind, arranged in a mathematical precision designed to teach us the Secret of a new physics that could lift us back to the stars? Does the planet have an automated defense shield that swallows up robotic probes if they wander int...

  1. Grasses as invasive plants in South Africa revisited: Patterns, pathways and management

    Directory of Open Access Journals (Sweden)

    Vernon Visser

    2017-03-01

    Full Text Available Background: In many countries around the world, the most damaging invasive plant species are grasses. However, the status of grass invasions in South Africa has not been documented recently. Objectives: To update Sue Milton’s 2004 review of grasses as invasive alien plants in South Africa, provide the first detailed species level inventory of alien grasses in South Africa and assess the invasion dynamics and management of the group. Method: We compiled the most comprehensive inventory of alien grasses in South Africa to date using recorded occurrences of alien grasses in the country from various literature and database sources. Using historical literature, we reviewed past efforts to introduce alien grasses into South Africa. We sourced information on the origins, uses, distributions and minimum residence times to investigate pathways and patterns of spatial extent. We identified alien grasses in South Africa that are having environmental and economic impacts and determined whether management options have been identified, and legislation created, for these species. Results: There are at least 256 alien grass species in the country, 37 of which have become invasive. Alien grass species richness increased most dramatically from the late 1800s to about 1940. Alien grass species that are not naturalised or invasive have much shorter residence times than those that have naturalised or become invasive. Most grasses were probably introduced for forage purposes, and a large number of alien grass species were trialled at pasture research stations. A large number of alien grass species in South Africa are of Eurasian origin, although more recent introductions include species from elsewhere in Africa and from Australasia. Alien grasses are most prevalent in the south-west of the country, and the Fynbos Biome has the most alien grasses and the most widespread species. We identified 11 species that have recorded environmental and economic impacts in the

  2. Measurement of alienation among adolescents:

    DEFF Research Database (Denmark)

    Rayce, Signe Boe; Kreiner, Svend; Trab Damsgaard, Mogens

    2018-01-01

    Background Psychological alienation is an important concept in the study of adolescents’ health and behavior but no gold standard for measuring alienation among adolescents exists. There is a need for new scales with high validity for use in adolescent health and social research. The purpose...... using graphical loglinear Rasch models (GLLRM). Results The three scales each comprised three to five face valid items. The powerlessness scale reflected the adolescent’s expectancy as to whether his/her behavior can determine the outcome or reinforcement he/she seeks. The meaninglessness scale...... and differential item functioning. However, only to a limited degree, which could be accounted for using GLLRM. Thus the scales fitted GLLRMs and can therefore be considered to be essentially construct valid and essentially objective. Conclusion The three alienation scales appear to be content and face valid...

  3. 8 CFR 1214.2 - Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration...

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Review of alien victims of severe forms of trafficking in persons; aliens in pending immigration proceedings. 1214.2 Section 1214.2 Aliens and... NONIMMIGRANT CLASSES § 1214.2 Review of alien victims of severe forms of trafficking in persons; aliens in...

  4. 33 CFR 125.25 - Aliens.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Aliens. 125.25 Section 125.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) WATERFRONT....25 Aliens. Alien registration records together with other papers and documents which indicated the...

  5. Expanding the Parameters of Parental Alienation Syndrome.

    Science.gov (United States)

    Cartwright, Glenn F.

    1993-01-01

    Because parental alienation syndrome is newly recognized, it must be redefined as new cases are observed. Evidence suggests that alienation may be provoked by other than custodial matters, cases of alleged sexual abuse may be hinted, slow judgments by courts exacerbate problem, prolonged alienation of child may trigger mental illness, and little…

  6. Interaction Effects of Students, Drugs and Alienation

    Science.gov (United States)

    Jones, Woodrow, Jr.

    1977-01-01

    This study examined the interaction effect of students, drugs, and alienation in a large university, i.e., the linkages of both social and political alienation with drug behavior. The interaction terms which composed these forms of alienation were evaluated as to their comparative ability to produce drug behavior. (Author)

  7. Policy alienation of public professionals: the effects

    NARCIS (Netherlands)

    L.G. Tummers (Lars)

    2008-01-01

    textabstractNowadays, many public professionals face identification problems towards public policies they have to implement; that is, they experience policy alienation. We conceptualize policy alienation, starting from the sociological concept of alienation and showing how this can be used in the

  8. Energy Extraction from a Slider-Crank Wave Energy under Irregular Wave Conditions: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Sang, Yuanrui; Karayaka, H. Bora; Yan, Yanjun; Zhang, James Z.; Muljadi, Eduard; Yu, Yi-Hsiang

    2015-08-24

    A slider-crank wave energy converter (WEC) is a novel energy conversion device. It converts wave energy into electricity at a relatively high efficiency, and it features a simple structure. Past analysis on this particular WEC has been done under regular sinusoidal wave conditions, and suboptimal energy could be achieved. This paper presents the analysis of the system under irregular wave conditions; a time-domain hydrodynamics model is adopted and a rule-based control methodology is introduced to better serve the irregular wave conditions. Results from the simulations show that the performance of the system under irregular wave conditions is different from that under regular sinusoidal wave conditions, but a reasonable amount of energy can still be extracted.

  9. On the Performance of Pivoted Curved Slider Bearings: Rabinowitsch Fluid Model

    Directory of Open Access Journals (Sweden)

    U.P. Singh

    2012-09-01

    Full Text Available The present theoretical analysis is to investigate the effect of nonNewtonian Pseudoplastic & Dilatant lubricants (lubricant blended with viscosity index improver–Rabinowitsch fluid model on the dynamic stiffness and damping characteristics of pivoted curved slider bearings. The modified Reynolds equation has been obtained for steady and damping states of the bearing. To analyze the steady state characteristics and dynamic characteristics, small perturbation theory has been adopted. The results for the steady state bearing performance characteristics (steady state film pressure, load carrying capacity and centre of pressure as well as dynamic stiffness and damping characteristics have been calculated numerically for various values of viscosity index improver using Mathematical 7.0 and it is concluded that these characteristics vary significantly with the non-Newtonian behavior of the fluid consistent with the real nature of the problem.

  10. The Affective Slider: A Digital Self-Assessment Scale for the Measurement of Human Emotions.

    Directory of Open Access Journals (Sweden)

    Alberto Betella

    Full Text Available Self-assessment methods are broadly employed in emotion research for the collection of subjective affective ratings. The Self-Assessment Manikin (SAM, a pictorial scale developed in the eighties for the measurement of pleasure, arousal, and dominance, is still among the most popular self-reporting tools, despite having been conceived upon design principles which are today obsolete. By leveraging on state-of-the-art user interfaces and metacommunicative pictorial representations, we developed the Affective Slider (AS, a digital self-reporting tool composed of two slider controls for the quick assessment of pleasure and arousal. To empirically validate the AS, we conducted a systematic comparison between AS and SAM in a task involving the emotional assessment of a series of images taken from the International Affective Picture System (IAPS, a database composed of pictures representing a wide range of semantic categories often used as a benchmark in psychological studies. Our results show that the AS is equivalent to SAM in the self-assessment of pleasure and arousal, with two added advantages: the AS does not require written instructions and it can be easily reproduced in latest-generation digital devices, including smartphones and tablets. Moreover, we compared new and normative IAPS ratings and found a general drop in reported arousal of pictorial stimuli. Not only do our results demonstrate that legacy scales for the self-report of affect can be replaced with new measurement tools developed in accordance to modern design principles, but also that standardized sets of stimuli which are widely adopted in research on human emotion are not as effective as they were in the past due to a general desensitization towards highly arousing content.

  11. The Affective Slider: A Digital Self-Assessment Scale for the Measurement of Human Emotions.

    Science.gov (United States)

    Betella, Alberto; Verschure, Paul F M J

    2016-01-01

    Self-assessment methods are broadly employed in emotion research for the collection of subjective affective ratings. The Self-Assessment Manikin (SAM), a pictorial scale developed in the eighties for the measurement of pleasure, arousal, and dominance, is still among the most popular self-reporting tools, despite having been conceived upon design principles which are today obsolete. By leveraging on state-of-the-art user interfaces and metacommunicative pictorial representations, we developed the Affective Slider (AS), a digital self-reporting tool composed of two slider controls for the quick assessment of pleasure and arousal. To empirically validate the AS, we conducted a systematic comparison between AS and SAM in a task involving the emotional assessment of a series of images taken from the International Affective Picture System (IAPS), a database composed of pictures representing a wide range of semantic categories often used as a benchmark in psychological studies. Our results show that the AS is equivalent to SAM in the self-assessment of pleasure and arousal, with two added advantages: the AS does not require written instructions and it can be easily reproduced in latest-generation digital devices, including smartphones and tablets. Moreover, we compared new and normative IAPS ratings and found a general drop in reported arousal of pictorial stimuli. Not only do our results demonstrate that legacy scales for the self-report of affect can be replaced with new measurement tools developed in accordance to modern design principles, but also that standardized sets of stimuli which are widely adopted in research on human emotion are not as effective as they were in the past due to a general desensitization towards highly arousing content.

  12. Update of marine alien species in Hellenic waters

    Directory of Open Access Journals (Sweden)

    M.A. PANCUCCI-PAPADOPOULOU

    2005-11-01

    Full Text Available The list of marine alien species in Hellenic waters is updated taking into account new findings (published and unpublished data. According to the present work, the number of these species has increased from 90 (known until end 2003 to 128. Most of them are zoobenthic species followed by fish and macroalgae. An interannual analysis revealed an important increase of alien species during the last years. The study of their geographic distribution showed that their majority is present in the southeastern Aegean. More than 55% of them are well established, while about 40% are casual records. Their main pathway of introduction seems to be the Suez Canal followed by shipping, whereas the Straits of Gibraltar, aquaculture and the Straits of Dardanelles appear to play a less important role in their invasion of Hellenic waters. These findings are discussed considering environmental and anthropogenic factors.

  13. Functional differences between native and alien species: a global-scale comparison

    DEFF Research Database (Denmark)

    Ordonez Gloria, Alejandro

    2010-01-01

    1. A prevalent question in the study of plant invasions has been whether or not invasions can be explained on the basis of traits. Despite many attempts, a synthetic view of multi-trait differences between alien and native species is not yet available.2. We compiled a database of three ecologically...... important traits (specific leaf area, typical maximum canopy height, individual seed mass) for 4473 species sampled over 95 communities (3784 species measured in their native range, 689 species in their introduced range, 207 in both ranges).3. Considering each trait separately, co-occurring native and alien...... species significantly differed in their traits. These differences, although modest, were expressed in a combined 15% higher specific leaf area, 16% lower canopy height and 26% smaller seeds.4. Using three novel multi-trait metrics of functional diversity, aliens showed significantly smaller trait ranges...

  14. Alien smuggling: East to West.

    Science.gov (United States)

    Walsh, J H

    1987-01-01

    This year untold millions of illegal aliens will enter Western Europe, Canada, and the US; in 1986, the US alone made 1.7 million apprehensions. Because of the numbers involved and the hard currency exchanged, alien smuggling has become big business--a lucrative track in desparate human beings. West Germany's open door asylum policy has been a boon to the smugglers, and West Berlin is currently a favored port of entry. The government provides social benefits--apartments, food, a stipend, and clothing--for asylum seekers. Smuggling operations appear to fit 3 categories: 1) state-sponsored alien smugglers, with a sub-category of terrorists; 2) ethnic smugglers with a history of terrorist spinoffs; and 3) independent smugglers, who are profit oriented, and willing to handle ethnic aliens and terrorists. In West Germany, immigration investigations begin at the border. West German officials often know that as they cause the Eastern border to be tightened, the flow will gravitate south toward Austria. Redirecting the trasit of Third Worlders from East Berlin away from West Germany, Sweden, and Denmark will be a stop-gap measure at best. Part of West Germany's immigration problem can be traced to the Basic Law that provides asylum for those who claim persecution (political, racial, ethnic, or religious). Yet, any attempt to change asylum would result in an admission of defeat in the quest for a unified Germany. Should Austria move to tighten its immigration laws, agreements similar to those between East and West Germany will likely follow.

  15. The Mexican "Illegal Alien" Commute.

    Science.gov (United States)

    Decker, Phil

    1986-01-01

    A photo report of the following three treks by illegal aliens across the border from Mexico to work in Arizona reveals the dangers and disappointments the migrants are exposed to: (1) a "carpool" from Southern Mexico; (2) a train ride from Sinaloa; and (3) a 40-mile hike through the Arizona desert. (PS)

  16. Geographical constraints are stronger than invasion patterns for European urban floras.

    Science.gov (United States)

    Ricotta, Carlo; Celesti-Grapow, Laura; Kühn, Ingolf; Rapson, Gillian; Pyšek, Petr; La Sorte, Frank A; Thompson, Ken

    2014-01-01

    Understanding the mechanisms that affect invasion success of alien species is an important prerequisite for the effective management of present and future aliens. To gain insight into this matter we asked the following questions: Are the geographical patterns of species distributions in urban floras different for native compared with alien plant species? Does the introduction of alien species contribute to the homogenization of urban floras? We used a Mantel test on Jaccard dissimilarity matrices of 30 urban floras across the British Isles, Italy and central Europe to compare the spatial distribution of native species with four classes of alien species: archaeophytes, all neophytes, non-invasive neophytes, and invasive neophytes. Archaeophytes and neophytes are species that were introduced into Europe before and after 1500 AD, respectively. To analyze the homogenizing effect of alien species on the native urban floras, we tested for differences in the average dissimilarity of individual cities from their group centroid in ordination space. Our results show that the compositional patterns of native and alien species seem to respond to the same environmental drivers, such that all four classes of alien species were significantly related to native species across urban floras. In this framework, alien species may have an impact on biogeographic patterns of urban floras in ways that reflect their history of introduction and expansion: archaeophytes and invasive neophytes tended to homogenize, while non-invasive neophytes tended to differentiate urban floras.

  17. Geographical constraints are stronger than invasion patterns for European urban floras.

    Directory of Open Access Journals (Sweden)

    Carlo Ricotta

    Full Text Available Understanding the mechanisms that affect invasion success of alien species is an important prerequisite for the effective management of present and future aliens. To gain insight into this matter we asked the following questions: Are the geographical patterns of species distributions in urban floras different for native compared with alien plant species? Does the introduction of alien species contribute to the homogenization of urban floras? We used a Mantel test on Jaccard dissimilarity matrices of 30 urban floras across the British Isles, Italy and central Europe to compare the spatial distribution of native species with four classes of alien species: archaeophytes, all neophytes, non-invasive neophytes, and invasive neophytes. Archaeophytes and neophytes are species that were introduced into Europe before and after 1500 AD, respectively. To analyze the homogenizing effect of alien species on the native urban floras, we tested for differences in the average dissimilarity of individual cities from their group centroid in ordination space. Our results show that the compositional patterns of native and alien species seem to respond to the same environmental drivers, such that all four classes of alien species were significantly related to native species across urban floras. In this framework, alien species may have an impact on biogeographic patterns of urban floras in ways that reflect their history of introduction and expansion: archaeophytes and invasive neophytes tended to homogenize, while non-invasive neophytes tended to differentiate urban floras.

  18. Which Factors Affect the Success or Failure of Eradication Campaigns against Alien Species?

    NARCIS (Netherlands)

    Pluess, T.; Jarošík, V.; Pysek, P.; Cannon, R.; Pergl, J.; Breukers, A.; Bacher, S.

    2012-01-01

    Although issues related to the management of invasive alien species are receiving increasing attention, little is known about which factors affect the likelihood of success of management measures. We applied two data mining techniques, classification trees and boosted trees, to identify factors that

  19. The impact and control of alien aquatic vegetation in South African ...

    African Journals Online (AJOL)

    The impact and control of alien aquatic vegetation in South African aquatic ecosystems. MP Hill. Abstract. Water hyacinth, water lettuce, salvinia, parrot's feather and red water fern are South American aquatic plant species that have become invasive in aquatic ecosystems in South Africa. The lack of indigenous natural ...

  20. Czech alien flora and the historical pattern of its formation: what came first to Central Europe?

    Czech Academy of Sciences Publication Activity Database

    Pyšek, Petr; Sádlo, Jiří; Mandák, Bohumil; Jarošík, V.

    2003-01-01

    Roč. 135, - (2003), s. 122-130 ISSN 0029-8549 R&D Projects: GA AV ČR KSK6005114; GA ČR GA206/99/1239 Institutional research plan: CEZ:AV0Z6005908 Keywords : alien flora * immigration pattern * invasion history Subject RIV: EF - Botanics Impact factor: 3.128, year: 2003

  1. Alien plants in checklist and floras: towards better communication between taxonomists and ecologists

    Czech Academy of Sciences Publication Activity Database

    Pyšek, Petr; Richardson, D. M.; Rejmánek, M.; Webster, G. L.; Williamson, M.; Kirschner, Jan

    2004-01-01

    Roč. 53, č. 1 (2004), s. 131-143 ISSN 0040-0262 R&D Projects: GA AV ČR KSK6005114; GA ČR GA206/03/1216 Institutional research plan: CEZ:AV0Z6005908 Keywords : alien * biological invasions * standard floras Subject RIV: EF - Botanics Impact factor: 1.752, year: 2004

  2. Alien and translocated aquatic animals in Southern Africa: a general introduction, checklist and bibliography

    CSIR Research Space (South Africa)

    Bruton, MN

    1985-01-01

    Full Text Available A list of references to research and records of alien and translocated aquatic animals in southern Africa is given, as well as a general introduction to the problem of invasive aquatic animals. Reference is made to 5&7 publications. The genera...

  3. Recovery of South African fynbos vegetation following alien woody plant clearing and fire: implications for restoration

    CSIR Research Space (South Africa)

    Holmes, PM

    2000-12-01

    Full Text Available The recovery of fynbos vegetation after invasion by dense stands of alien trees, and clearing by either 'burn standing’,’ fell and burn', or 'fell, remove and burn' treatments, was investigated in two watersheds in the Western Cape Province, South...

  4. Searching for Alien Life Having Unearthly Biochemistry

    Science.gov (United States)

    Jones, Harry

    2003-01-01

    The search for alien life in the solar system should include exploring unearth-like environments for life having an unearthly biochemistry. We expect alien life to conform to the same basic chemical and ecological constraints as terrestrial life, since inorganic chemistry and the laws of ecosystems appear to be universal. Astrobiologists usually assume alien life will use familiar terrestrial biochemistry and therefore hope to find alien life by searching near water or by supplying hydrocarbons. The assumption that alien life is likely to be based on carbon and water is traditional and plausible. It justifies high priority for missions to search for alien life on Mars and Europa, but it unduly restricts the search for alien life. Terrestrial carbon-water biochemistry is not possible on most of the bodies of our solar system, but all alien life is not necessarily based on terrestrial biochemistry. If alien life has a separate origin from Earth life, and if can survive in an environment extremely different from Earth's, then alien life may have unearthly biochemistry. There may be other solvents than water that support alien life and other elements than carbon that form complex life enabling chain molecules. Rather than making the exploration-restricting assumption that all life requires carbon, water, and terrestrial biochemistry, we should make the exploration-friendly assumption that indigenous, environmentally adapted, alien life forms might flourish using unearthly biochemistry in many places in the solar system. Alien life might be found wherever there is free energy and a physical/chemical system capable of using that energy to build living structures. Alien life may be discovered by the detection of some general non-equilibrium chemistry rather than of terrestrial biochemistry. We should explore all the potential abodes of life in the solar system, including those where life based on terrestrial biochemistry can not exist.

  5. Trade-associated pathways of alien forest insect entries in Canada

    Science.gov (United States)

    Denys Yemshanov; Frank H. Koch; Mark Ducey; Klaus Koehler

    2012-01-01

    Long-distance introductions of new invasive species have often been driven by socioeconomic factors, such that traditional ‘‘biological’’ invasion models may not be capable of estimating spread fully and reliably. In this study we present a new methodology to characterize and predict pathways of human-assisted entries of alien forest insects. We have developed a...

  6. Germination Response of Four Alien Congeneric Amaranthus Species to Environmental Factors.

    Science.gov (United States)

    Hao, Jian-Hua; Lv, Shuang-Shuang; Bhattacharya, Saurav; Fu, Jian-Guo

    2017-01-01

    Seed germination is the key step for successful establishment, growth and further expansion of population especially for alien plants with annual life cycle. Traits like better adaptability and germination response were thought to be associated with plant invasion. However, there are not enough empirical studies correlating adaptation to environmental factors with germination response of alien invasive plants. In this study, we conducted congeneric comparisons of germination response to different environmental factors such as light, pH, NaCl, osmotic and soil burials among four alien amaranths that differ in invasiveness and have sympatric distribution in Jiangsu Province, China. The data were used to create three-parameter sigmoid and exponential decay models, which were fitted to cumulative germination and emergence curves. The results showed higher maximum Germination (Gmax), shorter time for 50% germination (G50) and the rapid slope (Grate) for Amaranthus blitum (low-invasive) and A. retroflexus (high-invasive) compare to intermediately invasive A. spinosus and A. viridis in all experimental regimes. It indicated that germination potential does not necessarily constitute a trait that can efficiently distinguish highly invasive and low invasive congeners in four Amaranthus species. However, it was showed that the germination performances of four amaranth species were more or less correlated with their worldwide distribution area. Therefore, the germination performance can be used as a reference indicator, but not an absolute trait for invasiveness. Our results also confirmed that superior germination performance in wide environmental conditions supplementing high seed productivity in highly invasive A. retroflexus might be one of the reasons for its prolific growth and wide distribution. These findings lay the foundation to develop more efficient weed management practice like deep burial of seeds by turning over soil and use of tillage agriculture to control

  7. Food selection of a generalist herbivore exposed to native and alien seaweeds.

    Science.gov (United States)

    Noè, Simona; Badalamenti, Fabio; Bonaviri, Chiara; Musco, Luigi; Fernández, Tomás Vega; Vizzini, Salvatrice; Gianguzza, Paola

    2017-10-24

    Understanding which factors influence the invasion of alien seaweed has become a central concern in ecology. Increasing evidence suggests that the feeding preferences of native herbivores influence the success of alien seaweeds in the new community. We investigated food selection of a generalist native grazer Paracentrotus lividus, in the presence of two alien seaweeds (Caulerpa cylindracea and Caulerpa taxifolia var. distichophylla) and two native seaweeds (Dictyopteris membranacea and Cystoseira compressa). Sea urchins were fed with six experimental food items: C. cylindracea, C. taxifolia var. distichophylla, a mixture of C. cylindracea and C. taxifolia var. distichophylla, D. membranacea, C. compressa and a mixture of D. membranacea and C. compressa. P. lividus ingested all the combinations of food offered, though it preferentially consumed the alien mixture, C. cylindracea and D. membranacea. The alien C. taxifolia var. distichophylla was consumed significantly less than the other food items and, interestingly, it was ingested in a greater amount when mixed with C. cylindracea than when on its own. This finding suggests that C. taxifolia var. distichophylla may become vulnerable to sea urchin grazing when it grows intermingled with C. cylindracea, which does not gain immediate protection from the presence of the very low palatable congeneric seaweed. The present study highlights the potential role of native grazers to indirectly affect the interspecific competition between the two alien seaweeds in the Mediterranean Sea. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Invasive species unchecked by climate - response

    DEFF Research Database (Denmark)

    Burrows, Michael T.; Schoeman, David S.; Duarte, Carlos M.

    2012-01-01

    Hulme points out that observed rates of range expansion by invasive alien species are higher than the median speed of isotherm movement over the past 50 years, which in turn has outpaced the rates of climate-associated range changes of marine and terrestrial species. This is not surprising, given...... the many ecological and anthropogenic processes that combine to facilitate the translocation of invasive species and the subsequent expansion of their populations. Successful alien species have been observed to rapidly expand their ranges until some limit, typically climate-imposed, is reached. Comparisons...... of climate-change-induced range shifts between native and alien species are meaningful only after the initial invasive spread has reached a stable range boundary. A focus on regions with high velocities of climate change, and on regions such as the tropics where novel thermal niches are being created, should...

  9. Invasive ornamental fish: a potential threat to aquatic biodiversity in peninsular India

    Directory of Open Access Journals (Sweden)

    J.D.M. Knight

    2010-02-01

    Full Text Available Alien fish find their way into newer habitats and ecosystems opportunistically. Once in a new habitat, these species try to occupy empty niches and compete with native species. An alien species becomes invasive wherever it has a competetive advantage over native species. Ecology of aquatic invasive alien species is rather poorly understood as most attention has been on invertebrates as that which spread through ballast water. Invasive alien species of fish that have taken advantage of the aquarium trade are emerging as the most important threats to fragile aquatic habitats. Regulations to this trade are rather weak and there is a general lack of data on the ecological impact of alien fish species despite the fact that a third of the world’s worst aquatic invasive species are aquarium or ornamental species.

  10. Spreading of alien species and diversity of communities

    Czech Academy of Sciences Publication Activity Database

    Kindlmann, Pavel; Honěk, A.; Martinková, Z.

    2017-01-01

    Roč. 62, č. 3 (2017), s. 397-407 ISSN 1386-6141 R&D Projects: GA ČR GA14-26561S; GA MŠk(CZ) LO1415 Institutional support: RVO:86652079 Keywords : pallas coleoptera-coccinellidae * lady beetle coleoptera * harmonia-axyridis * harlequin ladybird * intraguild predation * geographical-distribution * generalist predators * biological-control * invasion history * native range * Alien species * Native species * Ladybirds * Aphid predators * Simulation model * Community Subject RIV: EH - Ecology, Behaviour OBOR OECD: Biodiversity conservation Impact factor: 1.918, year: 2016

  11. 8 CFR 236.2 - Confined aliens, incompetents, and minors.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Confined aliens, incompetents, and minors. 236.2 Section 236.2 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL OF ALIENS ORDERED REMOVED Detention...

  12. 22 CFR 42.22 - Returning resident aliens.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at the...

  13. 8 CFR 1241.30 - Aliens ordered deported.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Aliens ordered deported. 1241.30 Section 1241.30 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF ALIENS ORDERED REMOVED Deportation of Aliens in the...

  14. 8 CFR 1241.20 - Aliens ordered excluded.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Aliens ordered excluded. 1241.20 Section 1241.20 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF ALIENS ORDERED REMOVED Deportation of Excluded Aliens...

  15. [A case of parental alienation].

    Science.gov (United States)

    Menz, Wolfgang

    2014-01-01

    The clinical term "Parental Alienation Syndrome" (PAS) was introduced in 1984 by Richard Gardner, an American psychiatrist. Gardner described PAS and its symptoms, as a personality disorder, which appears chiefly in connection to child custody disputes wherein a child turns suddenly and massively against the non-custodial parent without reasonable grounds for doing so. This action by the child is a result of the custodial parent's emotionally abusive attempts to incite the child against the non-custodial parent.Where the child's rejection is based on some real past experience, there is not PAS. PAS only occurs as a result of the custodial parent's actions. Despite intensive effort, PAS was not included in the new DSM-V. In this case, a particularly impressive case history of parental alienation is described and discussed.

  16. Uncertainties and validation of alien species catalogues: The Mediterranean as an example

    Science.gov (United States)

    Zenetos, Argyro; Çinar, Melih Ertan; Crocetta, Fabio; Golani, Dani; Rosso, Antonietta; Servello, Gianna; Shenkar, Noa; Turon, Xavier; Verlaque, Marc

    2017-05-01

    The meticulous revision by taxonomic experts of established alien species in the Mediterranean resulted in a major revision of the list proposed by Galil et al. (2016), with 73 species to be excluded (35 species categorised as non-established and 37 as not true aliens), and 72 species added to the list. Consequently, by year 2016 the total number of established alien species in the Mediterranean reached 613, which is a 28% increase over the preceding four years. If we also consider casual species (208 species), the total number of alien species in the Mediterranean is 821. This is attributed to: new findings, change in establishment status of species previously known on the basis of few and scattered records, and results of phylogenetic studies in some cosmopolitan species. However, the true number of alien species reported here is considered to be an underestimation, as it does not include phytoplanktonic organisms, Foraminifera, cryptogenic and species known on the basis of questionable records that might turn out to be true aliens. EASIN and INVASIVESNET can play a major role in the future revision/update of the present list, which currently serves for assessing indicators that are necessary for policy, and for management of alien species in the Mediterranean Sea. An increasing trend in new arrivals since 1950, which culminated in the 2001-2010 period, appeared to decline after 2010. Whether this negative trend is an indication of improvement, or is an artefact, remains to be seen. The current list provides a reliable updated database from which to continue monitoring the arrival and spread of invasive species in the Mediterranean, as well as to provide counsel to governmental agencies with respect to management and control. Current geographical, taxonomical and impact data gaps can be reduced only by instituting harmonised standards and methodologies for monitoring alien populations in all countries bordering the Mediterranean Sea.

  17. A rule-based phase control methodology for a slider-crank wave energy converter power take-off system

    Energy Technology Data Exchange (ETDEWEB)

    Sang, Yuanrui; Karayaka, H. Bora; Yan, Yanjun; Zhang, James Z.; Bogucki, Darek; Yu, Yi-Hsiang

    2017-09-01

    The slider crank is a proven mechanical linkage system with a long history of successful applications, and the slider-crank ocean wave energy converter (WEC) is a type of WEC that converts linear motion into rotation. This paper presents a control algorithm for a slider-crank WEC. In this study, a time-domain hydrodynamic analysis is adopted, and an AC synchronous machine is used in the power take-off system to achieve relatively high system performance. Also, a rule-based phase control strategy is applied to maximize energy extraction, making the system suitable for not only regular sinusoidal waves but also irregular waves. Simulations are carried out under regular sinusoidal wave and synthetically produced irregular wave conditions; performance validations are also presented with high-precision, real ocean wave surface elevation data. The influences of significant wave height, and peak period upon energy extraction of the system are studied. Energy extraction results using the proposed method are compared to those of the passive loading and complex conjugate control strategies; results show that the level of energy extraction is between those of the passive loading and complex conjugate control strategies, and the suboptimal nature of this control strategy is verified.

  18. Comparison of Gastrografin to barium sulfate as a gastrointestinal contrast agent in red-eared slider turtles (Trachemys scripta elegans).

    Science.gov (United States)

    Long, Charles Tyler; Page, Richard B; Howard, Antwain M; McKeon, Gabriel P; Felt, Stephen A

    2010-01-01

    Red-eared slider turtles (Trachemys scripta elegans) commonly develop intestinal obstruction. The gastrointestinal transit time in turtles tends to be longer than in other animals, making a rapid diagnosis of obstruction difficult. Fifteen red-eared sliders were given either Gastrografin or 30% w/v barium sulfate orally to compare ease of administration, transit time, and image quality. Each contrast medium was easy to administer but barium sulfate had to be administered more slowly (mean = 40s) than Gastrografin (mean = 20s) to prevent regurgitation. The mean transit and emptying time of Gastrografin was at least 9 h faster than barium sulfate at all time points except gastric transit. Both contrast media had a smooth, uniform appearance that outlined the mucosa with well-defined margins within the stomach and proximal small intestine. Dilution of Gastrografin occurred as it progressed through the intestines, resulting in decreased opacity in the distal small intestine and colon. Pre-administration packed cell volume and total serum protein levels of four turtles receiving Gastrografin were compared with levels at 24-, 96-, and 168-hours postadministration as well as to four control turtles not receiving contrast medium. Packed cell volume and total serum protein levels did not significantly differ among the Gastrografin and control group. From a clinical perspective, administration of Gastrografin allows for quicker results with only minor hematologic changes in red-eared sliders, but visualization of this contrast medium in the lower gastrointestinal tract may be insufficient for an accurate diagnosis.

  19. Dielectric elastomer actuators using Slide-Ring Material® with increased permittivity

    International Nuclear Information System (INIS)

    Tsuchitani, Shigeki; Miki, Hirofumi; Sunahara, Tokiharu

    2015-01-01

    The inclusion of high permittivity nanoparticles in elastomeric materials for dielectric elastomer actuators (DEAs) is one promising method to achieve large strain at relatively low applied voltages. However, the addition of these nanoparticles tends to increase the stiffness of the elastomer and disturbs the actuation of the DEA. This is attributed to restriction of the chain motion in the elastomer by the nanoparticles. Slide-Ring Material ® (SRM) is a cross-linked polymeric material with freely movable cross-linking sites. The internal stresses in this structure are dramatically homogenized by the pulley effect; therefore, the restriction of chain motion due to the nanoparticles is expected to be significantly reduced. We have employed SRM as a host elastomer for a DEA with the addition of ferroelectric BaTiO 3 (BT) nanoparticles. The effects of BT addition on the permittivity, stiffness and viscosity of the SRM–BT nanocomposites, and the actuation strain of DEAs using SRM were evaluated. The permittivity of the nanocomposites increased linearly with the concentration of BT and reached 3.6 times that for pure SRM at 50 wt%. The elastic modulus and the viscosity remained almost constant up to 20 wt% and then decreased above this concentration. The actuation strain of a planar actuator using SRM and 50 wt% BT was four times larger than that of the DEA with pure SRM. (paper)

  20. Recorded and potential alien invertebrate pests in Finnish agriculture and horticulture

    Directory of Open Access Journals (Sweden)

    I. VÄNNINEN

    2008-12-01

    Full Text Available It is assumed that climate change will promote pest invasions and their establishment in new regions. We have updated the list of current alien invertebrate pest species in Finland and produced a list of potential new alien pests using a self-organizing map (SOM that ranks species in terms of their risk of entry into Finland. The 76 pest species recorded included 66 insects, 5 nematodes, 2 mites and 3 slugs. Nearly half of the alien species appeared to have invaded Finland during the last 48 years. The SOM analysis is considered a viable tool for identification of potentially high-risk invasive pests from among the multitude of potential alien invaders, and represents a useful complement to local expert knowledge-based risk assessment of potentially invasive pests. Along with the comparisons with databases of current and potential pest species, SOM analysis suggests that in the changing climate, the habitats at greatest risk from exotic pests in Finland are horticultural: orchards, ornamental hardy-nursery stocks, landscape and ornamental tree nurseries, and greenhouses.

  1. Index of Alien Impact: A method for evaluating potential ecological impact of alien plant species

    Science.gov (United States)

    Alien plant species are stressors to ecosystems and indicators of reduced ecosystem integrity. The magnitude of the stress reflects not only the quantity of aliens present, but also the quality of their interactions with native ecosystems. We develop an Index of Alien Impact (IAI...

  2. Can alien plants support generalist insect herbivores?

    Science.gov (United States)

    Douglas Tallamy; Meg Ballard; Vincent. D' Amico

    2009-01-01

    Rearing experiments were conducted to address two questions relevant to understanding how generalist lepidopteran herbivores interact with alien plants. We reared 10 yellow-striped armyworms (Spodoptera ornithogalli),...

  3. Comparing ecohydrological processes in alien vs. native ranges: perspectives from the endangered shrub Myricaria germanica

    Science.gov (United States)

    Michielon, Bruno; Campagnaro, Thomas; Porté, Annabel; Hoyle, Jo; Picco, Lorenzo; Sitzia, Tommaso

    2017-04-01

    Comparing the ecology of woody species in their alien and native ranges may provide interesting insights for theoretical ecology, invasion biology, restoration ecology and forestry. The literature which describes the biological evolution of successful plant invaders is rich and increasing. However, no general theories have been developed about the geomorphic settings which may limit or favour the alien woody species expansion along rivers. The aim of this contribution is to explore the research opportunities in the comparison of ecohydrological processes occurring in the alien vs. the native ranges of invasive tree and shrub species along the riverine corridor. We use the endangered shrub Myricaria germanica as an example. Myricaria germanica is an Euro-Asiatic pioneer species that, in the native range, develops along natural rivers, wide and dynamic. These conditions are increasingly limited by anthropogenic constraints in most European rivers. This species has been recently introduced in New Zealand, where it is spreading in some natural rivers of the Canterbury region (South Island). We present the current knowledge about the natural and anthropogenic factors influencing this species in its native range. We compare this information with the current knowledge about the same factors influencing M. germanica invasiveness and invasibility of riparian habitats in New Zealand. We stress the need to identify potential factors which could drive life-traits and growing strategies divergence which may hinder the application to the alien ranges of existing ecohydrological knowledge from native ranges. Moreover, the pattern of expansion of the alien range of species endangered in their native ranges opens new windows for research.

  4. Comparing functional similarity between a native and an alien slug in temperate rain forests of British Columbia

    Directory of Open Access Journals (Sweden)

    Mariano A. Rodriguez-Cabal

    2015-04-01

    Full Text Available The impacts of invasive alien species are greatest when they become dominant members of a community, introduce novel traits, and displace native species. Invasions by alien mollusks represent a novel context by which to compare trait differences between generalist native and introduced herbivores in terrestrial ecosystems. Here, we determined the abundance, habitat, feeding preferences, as well as the metabolic rate of the native Pacific banana slug (Ariolimax columbianus and the alien black slug (Arion rufus in the coastal forests of British Columbia, Canada. Through a series of observational and experimental studies, we found that alien slugs are more abundant, differ in their habitat preferences, and consumed more fungi (mushrooms than native banana slugs. Conversely, in an enclosures experiment we found that herbivory damage by native slugs was higher compared to enclosures with alien only and control enclosures. Finally, metabolic rates were similar for both slug species. These results suggest that alien black slugs possess a suite of traits that make them functionally different from native banana slugs.

  5. Spatial mismatch analysis among hotspots of alien plant species, road and railway networks in Germany and Austria.

    Directory of Open Access Journals (Sweden)

    Yanina Benedetti

    Full Text Available Road and railway networks are pervasive elements of all environments, which have expanded intensively over the last century in all European countries. These transportation infrastructures have major impacts on the surrounding landscape, representing a threat to biodiversity. Roadsides and railways may function as corridors for dispersal of alien species in fragmented landscapes. However, only few studies have explored the spread of invasive species in relationship to transport network at large spatial scales. We performed a spatial mismatch analysis, based on a spatially explicit correlation test, to investigate whether alien plant species hotspots in Germany and Austria correspond to areas of high density of roads and railways. We tested this independently of the effects of dominant environments in each spatial unit, in order to focus just on the correlation between occurrence of alien species and density of linear transportation infrastructures. We found a significant spatial association between alien plant species hotspots distribution and roads and railways density in both countries. As expected, anthropogenic landscapes, such as urban areas, harbored more alien plant species, followed by water bodies. However, our findings suggested that the distribution of neobiota is strongest correlated to road/railways density than to land use composition. This study provides new evidence, from a transnational scale, that alien plants can use roadsides and rail networks as colonization corridors. Furthermore, our approach contributes to the understanding on alien plant species distribution at large spatial scale by the combination with spatial modeling procedures.

  6. ELNAIS meets EASIN: distribution of marine alien species in Greece using EASIN mapping services and ELNAIS spatial data

    Directory of Open Access Journals (Sweden)

    S. KATSANEVAKIS

    2013-03-01

    Full Text Available The European Alien Species Information Network (EASIN was created with the aim to provide easy access to accurate information on alien species in Europe. EASIN allows the retrieval of spatial information from existing online data providers in order to produce integrated georeferenced distribution maps of alien species in Europe. In November 2012, a new data provider, the Ellenic Network on Aquatic Invasive Species (ELNAIS, joined EASIN; this has significantly increased the available georeferenced information on marine/estuarine alien species in Greek waters. Here, we use maps created by EASIN to show differences in patterns of distribution in Greece for the most abundant Phyla of marine alien species - Mollusca, Arthropoda, Chordata and Annelida. We also show that the two main pathways of introduction of marine alien species (Lessepsian migration and Shipping are related to different patterns of species spatial distribution in Greece. Overall, the tools provided by EASIN can greatly aid scientists and policy makers in obtaining high quality information on marine alien species in Greece, especially after the association with ELNAIS.

  7. NEW CONTRIBUTION TO THE STUDY OF ALIEN FLORA IN ROMANIA

    Directory of Open Access Journals (Sweden)

    SÎRBU CULIŢĂ

    2011-12-01

    Full Text Available In this paper, a number of seventeen alien plant species are presented, one of them being now for the first time reported in Romania (Sedum sarmentosum Bunge. Some species are mentioned for the first time in the flora of Moldavia (Aster novae-angliae L., Cenchrus incertus M. A. Curtis, Chenopodium pumilio R. Br., Fraxinus americana L., Lindernia dubia (L. Pennell, Petunia × atkinsiana D. Don, Solidago gigantea Aiton, Tagetes erecta L. or Transylvania (Kochia sieversiana (Pallas C. A. Mey., and some are reported from new localities (seven species. For each species, there are presented general data on the geographical origin, its distribution in Europe and worldwide, as well as its invasion history and current distribution in Romania. Some of these species manifest a remarkable spreading tendency, expanding their invasion area in Romania. Voucher specimens were deposited in the Herbarium of University of Agricultural Sciences and Veterinary Medicine Iaşi (IASI.

  8. Fanon and the Problem of Alienation.

    Science.gov (United States)

    Kessous, Naaman

    1987-01-01

    The notion of alienation as presented in the writings of Frantz Fanon needs a theoretical analysis which considers its economic, racial and political aspects. Marx wrote on alienation in a similar way portraying it as a self-fulfilling prophecy which is fraught with violence and dehumanization. (VM)

  9. The Category of Alienation in Educational Psychology

    Science.gov (United States)

    Osin, E. N.

    2017-01-01

    This paper discusses the explanatory possibilities and limitations of the concept of alienation within the framework of educational psychology studies. Research into various phenomena associated with alienation (frustration and burnout, extrinsic motivation, cynicism, etc.) is often limited by the ontological realm of the individual, whereas the…

  10. Legal Recognition of the Parental Alienation Syndrome.

    Science.gov (United States)

    Palmer, Nancy Rainey

    1988-01-01

    Addresses the parental alienation syndrome, which is the process by which one parent overtly or covertly speaks or acts in a derogatory manner to or about the other parent during or subsequent to a divorce proceeding, in an attempt to alienate the child or children from that other parent. (Author)

  11. School Bureaucratization and Alienation from High School

    Science.gov (United States)

    Anderson, Barry D.

    1973-01-01

    The major goals of this study are to identify dimensions of bureaucracy and alienation, to determine the relationship of these dimensions to second-order, or integrating, factors, and to determine the relationships between the integrating factors of bureaucratic structure and alienation. (Author)

  12. Alienation, Mass Society and Mass Culture.

    Science.gov (United States)

    Dam, Hari N.

    This monograph examines the nature of alienation in mass society and mass culture. Conceptually based on the "Gemeinschaft-Gesellschaft" paradigm of sociologist Ferdinand Tonnies, discussion traces the concept of alienation as it appears in the philosophies of Hegel, Marx, Kierkegaard, Sartre, and others. Dwight Macdonald's "A Theory of Mass…

  13. Alienating Students: Marxist Theory in Action

    Science.gov (United States)

    Thiele, Megan; Pan, Yung-Yi Dian; Molina, Devin

    2016-01-01

    Karl Marx's revolutionary call, "Workers of the World Unite," resonates with many in today's society. This article describes and assesses an easily reproducible classroom activity that simulates both alienating, and perhaps more importantly, non-alienating states of production as described by Marx. This hands-on learning activity gives…

  14. Space, time and aliens: charting the dynamic structure of Galápagos pollination networks.

    Science.gov (United States)

    Traveset, Anna; Chamorro, Susana; Olesen, Jens M; Heleno, Ruben

    2015-06-23

    Oceanic archipelagos are threatened by the introduction of alien species which can severely disrupt the structure, function and stability of native communities. Here we investigated the pollination interactions in the two most disturbed Galápagos Islands, comparing the three main habitats and the two seasons, and assessing the impacts of alien plant invasions on network structure. We found that the pollination network structure was rather consistent between the two islands, but differed across habitats and seasons. Overall, the arid zone had the largest networks and highest species generalization levels whereas either the transition between habitats or the humid habitat showed lower values. Our data suggest that alien plants integrate easily into the communities, but with low impact on overall network structure, except for an increase in network selectiveness. The humid zone showed the highest nestedness and the lowest modularity, which might be explained by the low species diversity and the higher incidence of alien plants in this habitat. Both pollinators and plants were also more generalized in the hot season, when networks showed to be more nested. Alien species (both plants and pollinators) represented a high fraction (∼56 %) of the total number of interactions in the networks. It is thus likely that, in spite of the overall weak effect we found of alien plant invasion on pollination network structure, these introduced species influence the reproductive success of native ones, and by doing so, they affect the functioning of the community. This certainly deserves further investigation. Published by Oxford University Press on behalf of the Annals of Botany Company.

  15. Survey of roadside alien plants in Hawai`i Volcanoes National Park and adjacent residential areas 2001-2005

    Science.gov (United States)

    Bio, Keali'i F.; Pratt, Linda W.; Jacobi, James D.

    2012-01-01

    The sides of all paved roads of Hawai`i Volcanoes National Park (HAVO) were surveyed on foot in 2001 to 2005, and the roadside presence of 240 target invasive and potentially invasive alien plant species was recorded in mile-long increments. Buffer zones 5–10 miles (8–16 km) long along Highway 11 on either side of the Kīlauea and Kahuku Units of the park, as well as Wright Road that passed by the disjunct `Ōla`a Tract Unit, were included in the survey. Highway 11 is the primary road through the park and a major island thoroughfare. Three residential subdivisions adjacent to the park were similarly surveyed in 0.5–1 mile (0.8–1.6 km) intervals in 2003, and data were analyzed separately. Two roads to the east and northeast were also surveyed, but data from these disjunct areas were analyzed separately from park roads. In total, 174 of the target alien species were observed along HAVO roads and buffers, exclusive of residential areas, and the mean number of target aliens per mile surveyed was 20.6. Highway 11 and its buffer zones had the highest mean number of target alien plants per mile (26.7) of all park roads, and the Mauna Loa Strip Road had the lowest mean (11.7). Segments of Highway 11 adjacent to HAVO and Wright Road next to `Ōla`a Tract had mean numbers of target alien per mile (24–47) higher than those of any internal road. Alien plant frequencies were summarized for each road in HAVO. Fifteen new records of vascular plants for HAVO were observed and collected along park roads. An additional 28 alien plant species not known from HAVO were observed along the buffer segments of Highway 11 adjacent to the park. Within the adjacent residential subdivisions, 65 target alien plant species were sighted along roadsides. At least 15 potentially invasive species not currently found within HAVO were observed along residential roads, and several other species found there have been previously eliminated from the park or controlled to remnant populations

  16. Alien seas oceans in space

    CERN Document Server

    Lopes, Rosaly

    2013-01-01

    In the early days of planetary observation, oceans were thought to exist in all corners of the Solar System. Carbonated seas percolated beneath the clouds of Venus. Features on the Moon's surface were given names such as "the Bay of Rainbows” and the "Ocean of Storms." With the advent of modern telescopes and spacecraft exploration these ancient concepts of planetary seas have been replaced by the reality of something even more exotic. Alien Seas serves up the current research, past beliefs, and new theories to offer a rich array of the "seas" on other worlds. It is organized by location and by the material composing the oceans under discussion, with expert authors penning chapters on their  specialty. Each chapter features new original art depicting alien seas, as well as the latest ground-based and spacecraft images. With the contributors as guides, readers can explore the wild seas of Jupiter's watery satellite Europa, believed similar in composition to battery acid. Saturn's planet-sized moon Titan see...

  17. Alien encounter a scientific novel

    CERN Document Server

    Schulze-Makuch, Dirk

    2014-01-01

    It has been nearly 100 years since the Apollo moon landings, when Jack and Vladimir, two astronauts on a mission to Venus, discover a mysterious void related to indigenous life on the planet. Subsequently more voids are detected on Earth, Mars, Titan, and, quite ominously, inside a planetoid emerging from the Kuiper belt. Jack is sent to investigate the voids in the Solar System and intercept the planetoid - which, as becomes increasingly clear, is inhabited by alien life forms. Jack and his crew will have little time to understand their alien biochemistry, abilities, behavior patterns, resilience, and technology, but also how these life forms relate to the voids. Humankind's first encounter with these exotic life forms couldn't be more fateful, becoming a race against time to save life on Earth and to reveal the true nature of the voids, which seem to be intrinsically related to life and the universe itself. In this novel, the author combines many topics related to state-of-the-art research in the field of...

  18. Update of alien fauna and new records from Tunisian marine waters

    Directory of Open Access Journals (Sweden)

    K. OUNIFI- BEN AMOR

    2015-01-01

    Full Text Available An updated inventory of alien marine fauna in coastal and offshore Tunisian waters is presented. Records were compiled from scientific and ‘grey’ publications, presentations at scientific meetings, theses presented in fulfillment of requirements towards MSc and PhD degrees, websites and personal observations. 136 alien species were recorded in Tunisian waters, 60 records in northern coasts, West Mediterranean and 76 in central and southern coasts, Central Mediterranean. Nearly half of the first sightings in Tunisian waters took place in the Gulf of Gabès. The dominant taxa are Crustancean (24%, Molluscs (23%, Fishes (19% and Annelida (13%. Twenty one species previously reported as aliens, were upon consideration, reclassified as range-expanding Atlantic species. Amathia verticillata, previously considered native to the Mediterranean, is reclassified as pseudoindigenous. Twenty one alien species are newly recorded from Tunisia, including 5 fish species, 5 polychaetes, 4 crustaceans, 4 molluscs, and one each schyphozoan, bryozoan and tunicate. The findings of Gibberulus gibberulus albus, Morula aspera and Calcinus latens, three species new to the Mediterranean, and of Actaedoes tomentosus, reported for the second time in the basin, are described. Species were classified according to their establishment status and their origins. This contribution highlights the dual origin of biological invasion in Tunisian waters (Red Sea and Atlantic, with slightly more species of Red Sea and Indo-Pacific origin (61,76%.  The impact of the alien species in Tunisian waters was discussed.

  19. Alien insects in Italy: comparing patterns from the regional to European level.

    Science.gov (United States)

    Inghilesi, Alberto F; Mazza, Giuseppe; Cervo, Rita; Gherardi, Francesca; Sposimo, Paolo; Tricarico, Elena; Zapparoli, Marzio

    2013-01-01

    The introduction of species outside their native range contributes to the loss of biodiversity, alters the structure and functioning of ecosystems, and damages economy and human health. Insects are one of the taxa with the highest frequency of introduction due to their high diversity, biological properties, and close association with human activities. Here, the allodiversity of Italian entomofauna was analyzed, with a focus on Tuscany (Central Italy). A list of alien insects in Tuscany is included. The status of the alien entomofauna in Italy was updated. The number of alien insects amounts to 122 in Tuscany and 923 in Italy. An introduction rate of 98 species per decade was estimated in Italy. In Tuscany, alien insects belong to 10 orders, mostly Coleoptera (38%), Hemiptera (Sternorrhyncha and Auchenorrhyncha) (23%), and Hymenoptera (13%). They have been most often introduced through vegetable items (ornamental plants or crops). Most species come from the Nearctic region (26%) and are both phytophagous (63%) and amphigonic (80%). Differences and similarities in introduction patterns and in insect abundances across orders among regional, national, and European scales, also considering worldwide abundances, are discussed. Finally, a paucity of information regarding the negative impacts of many species, except for economic pests, phytosanitary threats, and vectors of disease, is underlined. A deeper understanding of the alien insects' ecological impact might help designate policies aimed at preventing further introductions and control the invasive populations of already established species.

  20. Alien Insects in Italy: Comparing Patterns from the Regional to European Level

    Science.gov (United States)

    Inghilesi, Alberto F.; Mazza, Giuseppe; Cervo, Rita; Gherardi, Francesca; Sposimo, Paolo; Tricarico, Elena; Zapparoli, Marzio

    2013-01-01

    The introduction of species outside their native range contributes to the loss of biodiversity, alters the structure and functioning of ecosystems, and damages economy and human health. Insects are one of the taxa with the highest frequency of introduction due to their high diversity, biological properties, and close association with human activities. Here, the allodiversity of Italian entomofauna was analyzed, with a focus on Tuscany (Central Italy). A list of alien insects in Tuscany is included. The status of the alien entomofauna in Italy was updated. The number of alien insects amounts to 122 in Tuscany and 923 in Italy. An introduction rate of 98 species per decade was estimated in Italy. In Tuscany, alien insects belong to 10 orders, mostly Coleoptera (38%), Hemiptera (Sternorrhyncha and Auchenorrhyncha) (23%), and Hymenoptera (13%). They have been most often introduced through vegetable items (ornamental plants or crops). Most species come from the Nearctic region (26%) and are both phytophagous (63%) and amphigonic (80%). Differences and similarities in introduction patterns and in insect abundances across orders among regional, national, and European scales, also considering worldwide abundances, are discussed. Finally, a paucity of information regarding the negative impacts of many species, except for economic pests, phytosanitary threats, and vectors of disease, is underlined. A deeper understanding of the alien insects' ecological impact might help designate policies aimed at preventing further introductions and control the invasive populations of already established species. PMID:24219427

  1. The assessment of hull fouling as a mechanism for the introduction and dispersal of marine alien species in the main Hawaiian Islands through surveys at harbors on Oahu's southern and southwestern coasts during 2003 (NODC Accession 0001455)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Surveys for adult invertebrates that were part of the hull fouling communities were done to determine to what extent marine alien invasive species (AIS) are being...

  2. The assessment of hull fouling as a mechanism for the introduction and dispersal of alien species in the main Hawaiian Islands through surveys at harbors on Oahu's Southern and Southwestern Coasts during 2003 (NODC Accession 0001455)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Surveys for adult invertebrates that were part of the hull fouling communities were done to determine to what extent marine alien invasive species (AIS) are being...

  3. An extensive alien plant inventory from the inhabited areas of galapagos.

    Science.gov (United States)

    Guézou, Anne; Trueman, Mandy; Buddenhagen, Christopher Evan; Chamorro, Susana; Guerrero, Ana Mireya; Pozo, Paola; Atkinson, Rachel

    2010-04-21

    Plant invasions are causing habitat degradation in Galapagos. Problems are concentrated on the four inhabited islands. Plants introduced to rural areas in the humid highlands and urban areas on the arid coast act as foci for invasion of the surrounding Galapagos National Park. Here we present results of the most comprehensive inventory to date of alien vascular plants in the inhabited areas of Galapagos. The survey was conducted between 2002 and 2007, in 6031 properties (97% of the total) on Floreana, Isabela, San Cristobal and Santa Cruz Islands. In total 754 alien vascular plant taxa were recorded, representing 468 genera in 123 families. Dicotyledons represented 554 taxa, monocotyledons 183, there were 7 gymnosperms and 10 pteridophytes. Almost half (363) of the taxa were herbaceous. The most represented families were Fabaceae (sensu lato), Asteraceae and Poaceae. The three most recorded species in the humid rural areas were Psidium guajava, Passiflora edulis and Bryophyllum pinnatum, and in the dry urban areas, Aloe vera, Portulaca oleracea and Carica papaya. In total, 264 (35%) taxa were recorded as naturalized. The most common use for taxa was ornamental (52%). This extensive survey has increased the known alien vascular flora of Galapagos by 257 species, giving a ratio of alien to native taxa of 1.57:1. It provides a crucial baseline for plant invasion management in the archipelago and contributes data for meta analyses of invasion processes worldwide. A repeat of the survey in the future would act as an effective early detection tool to help avoid further invasion of the Galapagos National Park.

  4. An extensive alien plant inventory from the inhabited areas of galapagos.

    Directory of Open Access Journals (Sweden)

    Anne Guézou

    Full Text Available BACKGROUND: Plant invasions are causing habitat degradation in Galapagos. Problems are concentrated on the four inhabited islands. Plants introduced to rural areas in the humid highlands and urban areas on the arid coast act as foci for invasion of the surrounding Galapagos National Park. METHODOLOGY/PRINCIPAL FINDINGS: Here we present results of the most comprehensive inventory to date of alien vascular plants in the inhabited areas of Galapagos. The survey was conducted between 2002 and 2007, in 6031 properties (97% of the total on Floreana, Isabela, San Cristobal and Santa Cruz Islands. In total 754 alien vascular plant taxa were recorded, representing 468 genera in 123 families. Dicotyledons represented 554 taxa, monocotyledons 183, there were 7 gymnosperms and 10 pteridophytes. Almost half (363 of the taxa were herbaceous. The most represented families were Fabaceae (sensu lato, Asteraceae and Poaceae. The three most recorded species in the humid rural areas were Psidium guajava, Passiflora edulis and Bryophyllum pinnatum, and in the dry urban areas, Aloe vera, Portulaca oleracea and Carica papaya. In total, 264 (35% taxa were recorded as naturalized. The most common use for taxa was ornamental (52%. CONCLUSIONS/SIGNIFICANCE: This extensive survey has increased the known alien vascular flora of Galapagos by 257 species, giving a ratio of alien to native taxa of 1.57:1. It provides a crucial baseline for plant invasion management in the archipelago and contributes data for meta analyses of invasion processes worldwide. A repeat of the survey in the future would act as an effective early detection tool to help avoid further invasion of the Galapagos National Park.

  5. Non-Newtonian Effects of Second-Order Fluids on the Hydrodynamic Lubrication of Inclined Slider Bearings.

    Science.gov (United States)

    Apparao, Siddangouda; Biradar, Trimbak Vaijanath; Naduvinamani, Neminath Bhujappa

    2014-01-01

    Theoretical study of non-Newtonian effects of second-order fluids on the performance characteristics of inclined slider bearings is presented. An approximate method is used for the solution of the highly nonlinear momentum equations for the second-order fluids. The closed form expressions for the fluid film pressure, load carrying capacity, frictional force, coefficient of friction, and centre of pressure are obtained. The non-Newtonian second order fluid model increases the film pressure, load carrying capacity, and frictional force whereas the center of pressure slightly shifts towards exit region. Further, the frictional coefficient decreases with an increase in the bearing velocity as expected for an ideal fluid.

  6. Troubling travellers: are ecologically harmful alien species associated with particular introduction pathways?

    Directory of Open Access Journals (Sweden)

    Jan Pergl

    2017-01-01

    Full Text Available Prioritization of introduction pathways is seen as an important component of the management of biological invasions. We address whether established alien plants, mammals, freshwater fish and terrestrial invertebrates with known ecological impacts are associated with particular introduction pathways (release, escape, contaminant, stowaway, corridor and unaided. We used the information from the European alien species database DAISIE (www.europe-aliens.org supplemented by the EASIN catalogue (European Alien Species Information Network, and expert knowledge. Plants introduced by the pathways release, corridor and unaided were disproportionately more likely to have ecological impacts than those introduced as contaminants. In contrast, impacts were not associated with particular introduction pathways for invertebrates, mammals or fish. Thus, while for plants management strategies should be targeted towards the appropriate pathways, for animals, management should focus on reducing the total number of taxa introduced, targeting those pathways responsible for high numbers of introductions. However, regardless of taxonomic group, having multiple introduction pathways increases the likelihood of the species having an ecological impact. This may simply reflect that species introduced by multiple pathways have high propagule pressure and so have a high probability of establishment. Clearly, patterns of invasion are determined by many interacting factors and management strategies should reflect this complexity.

  7. Aliens.

    Directory of Open Access Journals (Sweden)

    Juliet Fall

    2008-06-01

    Full Text Available Berce du Caucase, Renouée du Japon, Séneçon du Cap, Solidage du Canada : le monde s’invite dans nos jardins et nos paysages. Or, cet exotisme botanique, longtemps valorisé et promu par les Sociétés d’acclimatation, est aujourd’hui perçu comme un important problème écologique. Hors des limites contrôlées de nos jardins publics ou privés, ces plantes nous envahissent. Elles se mobilisent, concurrencent nos espèces indigènes, se dotent de pouvoirs allergènes et nous nuisent. ...

  8. Aliens.

    OpenAIRE

    Juliet Fall; Laurent Matthey

    2008-01-01

    Berce du Caucase, Renouée du Japon, Séneçon du Cap, Solidage du Canada : le monde s’invite dans nos jardins et nos paysages. Or, cet exotisme botanique, longtemps valorisé et promu par les Sociétés d’acclimatation, est aujourd’hui perçu comme un important problème écologique. Hors des limites contrôlées de nos jardins publics ou privés, ces plantes nous envahissent. Elles se mobilisent, concurrencent nos espèces indigènes, se dotent de pouvoirs allergènes et nous nuisent. ......

  9. Population dynamics of the invasive fish, Gambusia affinis , in ...

    African Journals Online (AJOL)

    The alien invasive Gambusia affinis is one of the most widely introduced fish species on the planet, and has established in freshwater ecosystems across South Africa. The invasion ecology and, in particular, the population dynamics of the species in this country are, however, poorly understood. In this study the relative ...

  10. Freshwater crayfish invasions in South Africa: past, present and ...

    African Journals Online (AJOL)

    Freshwater crayfish invasions have been studied around the world, but less so in Africa, a continent devoid of native freshwater crayfish. The present study reviews historical and current information on alien freshwater crayfish species introduced into South Africa and aims to indicate which areas are at risk from invasion.

  11. Global networks for invasion science: benefits, challenges and guidelines

    DEFF Research Database (Denmark)

    Packer, Jasmin G.; Meyerson, Laura A.; Richardson, David M.

    2017-01-01

    Much has been done to address the challenges of biological invasions, but fundamental questions (e.g., which species invade? Which habitats are invaded? How can invasions be effectively managed?) still need to be answered before the spread and impact of alien taxa can be effectively managed. Ques...

  12. A conceptual framework for invasion in microbial communities

    DEFF Research Database (Denmark)

    Kinnunen, Marta; Dechesne, Arnaud; Proctor, Caitlin

    2016-01-01

    and consistent terminology nor always include rigorous interpretations of the processes behind invasion. Therefore, we suggest that a consistent set of definitions and a rigorous conceptual framework are needed. We define invasion in a microbial community as the establishment of an alien microbial type...

  13. Economic essays on marine invasive species and international fisheries agreements

    NARCIS (Netherlands)

    Walker, A.N.

    2016-01-01

    This thesis is divided into two parts, as explained in Chapter 1, which focus on different aspects of marine ecological change. Part A considers marine Invasive Alien Species (IAS), which are taxa introduced outside of their native range. The detrimental consequences of invasions for human

  14. Invasive species in east Africa: current status for informed policy ...

    African Journals Online (AJOL)

    Invasive alien species are the second leading cause of biodiversity loss in the world today. A number of hypotheses have been advanced to explain the proliferation of invasive species. These hypotheses include deficiency of natural enemies in the introduced range, increased competitive ability, increased resource ...

  15. Impact of Prosopis (mesquite) invasion and clearing on vegetation ...

    African Journals Online (AJOL)

    We evaluated the impact of Prosopis invasion and clearing on vegetation species composition and diversity (alien and indigenous species richness and cover) in Nama-Karoo rangeland on two sheep farms in the Beaufort ... Keywords: invasive plants – exotic, Nama-Karoo, plant community ecology, rehabilitation, semi-arid ...

  16. 45 CFR 1626.7 - Verification of eligible alien status.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Verification of eligible alien status. 1626.7... CORPORATION RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.7 Verification of eligible alien status. (a) An alien seeking representation shall submit appropriate documents to verify eligibility, unless the only...

  17. 42 CFR 435.139 - Coverage for certain aliens.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Coverage for certain aliens. 435.139 Section 435... Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those aliens...

  18. 8 CFR 235.3 - Inadmissible aliens and expedited removal.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Inadmissible aliens and expedited removal. 235.3 Section 235.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS INSPECTION OF PERSONS APPLYING FOR ADMISSION § 235.3 Inadmissible aliens and expedited removal. (a) Detention...

  19. 31 CFR 515.335 - Permanent resident alien.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Permanent resident alien. 515.335... Definitions § 515.335 Permanent resident alien. As used in § 515.208, the term permanent resident alien means an alien lawfully admitted for permanent residence into the United States. [61 FR 37386, July 18...

  20. 8 CFR 1235.3 - Inadmissible aliens and expedited removal.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Inadmissible aliens and expedited removal. 1235.3 Section 1235.3 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS INSPECTION OF PERSONS APPLYING FOR ADMISSION § 1235.3 Inadmissible aliens...

  1. 26 CFR 1.871-3 - Residence of alien seamen.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Residence of alien seamen. 1.871-3 Section 1.871... (CONTINUED) INCOME TAXES Nonresident Aliens and Foreign Corporations § 1.871-3 Residence of alien seamen. In order to determine whether an alien seaman is a resident of the United States for purposes of the income...

  2. 8 CFR 1236.2 - Confined aliens, incompetents, and minors.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Confined aliens, incompetents, and minors. 1236.2 Section 1236.2 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS APPREHENSION AND DETENTION OF INADMISSIBLE AND DEPORTABLE ALIENS; REMOVAL...

  3. 45 CFR 233.52 - Overpayment to aliens.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Overpayment to aliens. 233.52 Section 233.52... ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.52 Overpayment to aliens. A State Plan under title IV-A of the Social Security Act, shall provide that: (a) Any sponsor of an alien and the alien shall be...

  4. 22 CFR 40.92 - Aliens unlawfully present.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Aliens unlawfully present. 40.92 Section 40.92... UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.92 Aliens unlawfully present. (a) 3-year bar. An alien described in INA 212(a)(9)(B)(i)(I) shall be ineligible for a...

  5. 8 CFR 1240.38 - Fingerprinting of excluded aliens.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Fingerprinting of excluded aliens. 1240.38 Section 1240.38 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Exclusion of...

  6. 22 CFR 40.91 - Certain aliens previously removed.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Certain aliens previously removed. 40.91... IMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.91 Certain aliens previously removed. (a) 5-year bar. An alien who has been found inadmissible, whether as a result...

  7. 8 CFR 274a.3 - Continuing employment of unauthorized aliens.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Continuing employment of unauthorized aliens. 274a.3 Section 274a.3 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONTROL OF EMPLOYMENT OF ALIENS Employer Requirements § 274a.3 Continuing employment of...

  8. 28 CFR 0.47 - Alien property matters.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Alien property matters. 0.47 Section 0.47....47 Alien property matters. The Office of Alien Property shall be a part of the Civil Division: (a... Alien Property: (1) Exercising or performing all the authority, rights, privileges, powers, duties, and...

  9. 45 CFR 1626.5 - Alien status and eligibility.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Alien status and eligibility. 1626.5 Section 1626... RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.5 Alien status and eligibility. Subject to all other... may provide legal assistance to an alien who is present in the United States and who is within one of...

  10. 26 CFR 1.6654-6 - Nonresident alien individuals.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Nonresident alien individuals. 1.6654-6 Section....6654-6 Nonresident alien individuals. (a) In general. A nonresident alien individual is required to... gross income of a nonresident alien individual is such as to require making a payment of estimated...

  11. 47 CFR 90.115 - Foreign government and alien eligibility.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Foreign government and alien eligibility. 90... government and alien eligibility. (a) No station authorization in the radio services governed by this part....9(c) of this chapter) if such entity is: (1) An alien or the representative of any alien; (2) A...

  12. 8 CFR 204.6 - Petitions for employment creation aliens.

    Science.gov (United States)

    2010-01-01

    ..., Immigrant Petition by Alien Entrepreneur. The petition must be accompanied by the appropriate fee. Before a... classification as an alien entrepreneur may only be filed by any alien on his or her own behalf. (d) Priority date. The priority date of a petition for classification as an alien entrepreneur is the date the...

  13. Standardization of DNA extraction from invasive alien weed ...

    African Journals Online (AJOL)

    Tuoyo Aghomotsegin

    DNA isolation from the weed, Parthenium hysterophorus is complicated due to the presence of high amount of allelochemicals in the form of secondary metabolites that causes hindrance in extraction and enzymatic reactions. A modified and efficient DNA extraction from P. hysterophorus leaf has been developed.

  14. Invasive alien plant species used for the treatment of various ...

    African Journals Online (AJOL)

    Results: The study revealed that Schinus molle L., Catharanthus roseus (L.), Datura stramonium L., Opuntia stricta (Haw.) Haw., Opuntia ficus- indica, Sambucus canadensis L., Ricinus communis L., Melia azedarch L., Argemone ochroleuca and Eriobotrya japonica are used for treatment of various diseases such as chest ...

  15. The assessment of invasive alien plant species removal programs ...

    African Journals Online (AJOL)

    Yusuf Adam

    Yusuf Adama, Njoya S Ngetara, Syd Ramdhanib a School of Agricultural, Earth and Environmental Sciences, University of KwaZulu-Natal, Howard ... Shaanker, 2013). These species affect human health, agriculture, forestry and biodiversity .... 2.2 Field data collection and image processing. Field data for the classification of ...

  16. Satellite-based annual evaporation estimates of invasive alien plant ...

    African Journals Online (AJOL)

    The Surface Energy Balance Algorithm for Land (SEBAL) model, using MODIS satellite imagery, was used to estimate the annual total ET at 250 m pixel resolution. ET was estimated for 3 climatically different years for the Western Cape and KwaZulu-Natal. The average annual ET from areas under IAPs, native vegetation, ...

  17. The predatory impact of invasive alien smallmouth bass, Micropterus ...

    African Journals Online (AJOL)

    Teleostei: Centrarchidae), on indigenous fishes in a Cape Floristic Region ... The Rondegat River is home to five species of indigenous fish and is partially invaded by M. dolomieu, which has penetrated the lower river up to a waterfall barrier.

  18. Alienation in Irvine Welsh’s Trainspotting

    Directory of Open Access Journals (Sweden)

    B.A. Senekal

    2010-07-01

    Full Text Available This article examines how Melvin Seeman’s theory of alienation (1959 and modern alienation research manifest in Irvine Welsh’s “Trainspotting”. This is an important novel, not only because of its commercial success, but also because it depicts a specific marginalised subculture. Postmodernism and systems theory approaches, as well as changes in the social and political spheres have motivated researchers such as Geyer (1996, Kalekin-Fishman (1998 and Neal and Collas (2000 to reinterpret Seeman’s theory. This article attempts to incorporate this new theory of alienation in the analysis of contemporary fiction. Seeman identifies five aspects of alienation, namely powerlessness, meaninglessness, normlessness, social isolation and self-estrangement. Following Neal and Collas (2000, in particular, this article omits self-estrangement, but shows how the other four aspects of alienation have changed since Seeman’s formulation. It is argued that “Trainspotting” depicts a specific occurrence of alienation in modern western society, besides normlessness, meaninglessness, and social isolation, highlighting Seeman’s concept of powerlessness, in particular. The article further argues that applying Seeman’s theory of alienation in the study of contemporary literature provides a fresh theoretical approach that contributes to the understanding of how fiction engages with its environment.

  19. The occurrence of alien species in the settlement areas of the Kampinos National Park and its vicinity (Central Poland

    Directory of Open Access Journals (Sweden)

    Kirpluk Izabella

    2015-09-01

    Full Text Available Studies aimed at the identification of the range and method of spread of alien plant species in settlement areas in Kampinos National Park (KNP and its immediate vicinity were carried out in years 2012-2014. Special emphasis was put on surveying the sites of invasive alien species (IAS, and diagnosing potential threats posed to the natural and semi-natural vegetation of the national park by the IAS present in rural areas. We found 53 alien vascular plant species, including 40 invasive taxa which may potentially pose a threat to the ecosystems of KNP. Species encroaching from settlement areas to semi-natural and natural communities included: Bidens frondosa, Echinocystis lobata, Impatiens glandulifera, I. parviflora, Juncus tenuis, Lupinus polyphyllus, Reunoutria japonica and Solidago gigantea. Most of them were species from the highest invasiveness (IV and III classes in Poland. Similarity analysis carried out for all investigated localities with regard to all alien species, and only for invasive ones showed a clear division into separate groups: villages within the boundaries of the national park and villages outside the park.

  20. INVENTORY OF THE INVASIVE ALIE N PLANT SPECIES IN INDONESIA

    Directory of Open Access Journals (Sweden)

    SRI S UDARMIYATI T JITROSOEDIRDJO

    2005-01-01

    Full Text Available An inventory of the alien plant species in Indone sia based on the existing references and herbarium specimens concluded that 1936 alien plant species ar e found in Indonesia which belong to 187 families. Field studies should be done to get the complete figur es of alien plant species in Indonesia. Based on the existing figures of the plant species, the invasive alien plant species can be iden tified, followed by studies on the assessment of losses, biology, management and their possible utilizations. Alien plant species are imported to Indonesia for cultivation, collection of the botanical garden, as experimental plants or other curiosities. Aside from plants purposely imported, there are also introduced plant propagules conta-minating imported agricultural products. These alien plant species can be beneficial or have a potential of being invasive. The alien cultivated species consisted of 67% of the total number. More than half of the cultivated plants are ornamental plants. Some of th e species are naturalized or escaped from cultivation and become wild and invasive. Some other natura lized species, adapted well without any problems of invasion. There are 339 species or 17% of the species r ecorded as weeds. The highest record of weeds is found in the family of Poaceae (57 species, follo wed by Asteraceae (53 species and Cyperaceae (35 species. There are 6 families having more than 10 species of weeds: Amaranthaceae, Asteraceae, Cyperaceae, Euphorbiaceae, Poaceae, and Rubiaceae. Three families have more than 100 species: Asteraceae 162 species, Poaceae 120 species, and Papillionaceae 103 species. Five species of aquatic and 20 species of terrestrial plants considered as important alien plant species in Indonesia were identified and some of their distributions noted

  1. Rapid assessment of the invasive status of eucalyptus species in two South African provinces

    CSIR Research Space (South Africa)

    Forsyth, GG

    2004-01-01

    Full Text Available Gum trees, or eucalypts (Eucalyptus species), have been targeted for invasive alien plant clearing programmes in many parts of South Africa. This has caused some dissatisfaction where the species concerned also have useful characteristics...

  2. Effects of Lantana camara (L.) invasion on the native vegetation of ...

    African Journals Online (AJOL)

    . Lantana ... A total of 41 native woody species and 2 native herbaceous species were identified in the study area. Basal area ... in the area. Keywords : Alien plants, Biodiversity, Invasive plants, Lantana camara, Vegetation composition.

  3. Alien flora of Europe: species diversity, temporal trends, geographical patterns and research needs

    Czech Academy of Sciences Publication Activity Database

    Lambdon, P. W.; Pyšek, Petr; Basnou, C.; Hejda, Martin; Arianoutsou, M.; Essl, F.; Jarošík, Vojtěch; Pergl, Jan; Winter, M.; Anastasiu, P.; Andriopoulos, P.; Bazos, I.; Brundu, G.; Celesti-Grapow, L.; Chassot, P.; Delipetrou, P.; Josefsson, M.; Kark, S.; Klotz, S.; Kokkoris, Y.; Kühn, I.; Marchante, H.; Perglová, Irena; Pino, J.; Vila, M.; Zikos, A.; Roy, D.; Hulme, P. E.

    2008-01-01

    Roč. 80, č. 2 (2008), s. 101-149 ISSN 0032-7786 R&D Projects: GA AV ČR(CZ) IAA600050811; GA MŠk(CZ) LC06073 Grant - others:DAISIE(XE) SSPI-CT-2003-511202 Institutional research plan: CEZ:AV0Z60050516 Keywords : alien plants * Europe * invasion Subject RIV: EF - Botanics Impact factor: 2.396, year: 2008 http://www.ibot.cas.cz/preslia/P082Lam. pdf

  4. Pyrrolizidine alkaloid variation in Senecio vulgaris populations from native and invasive ranges

    NARCIS (Netherlands)

    Cheng, Dandan; Nguyen, Viet Thang; Ndihokubwayo, Noel; Ge, Jiwen; Mulder, Patrick P.J.

    2017-01-01

    Biological invasion is regarded as one of the greatest environmental problems facilitated by globalization. Some hypotheses about the invasive mechanisms of alien invasive plants consider the plant-herbivore interaction and the role of plant defense in this interaction. For example, the ``Shift

  5. Effects of increased soil nitrogen on the dominance of alien annual plants in the Mojave Desert

    Science.gov (United States)

    Brooks, Matthew L.

    2003-01-01

    1. Deserts are one of the least invaded ecosystems by plants, possibly due to naturally low levels of soil nitrogen. Increased levels of soil nitrogen caused by atmospheric nitrogen deposition may increase the dominance of invasive alien plants and decrease the diversity of plant communities in desert regions, as it has in other ecosystems. Deserts should be particularly susceptible to even small increases in soil nitrogen levels because the ratio of increased nitrogen to plant biomass is higher compared with most other ecosystems.2. The hypothesis that increased soil nitrogen will lead to increased dominance by alien plants and decreased plant species diversity was tested in field experiments using nitrogen additions at three sites in the in the Mojave Desert of western North America.3. Responses of alien and native annual plants to soil nitrogen additions were measured in terms of density, biomass and species richness. Effects of nitrogen additions were evaluated during 2 years of contrasting rainfall and annual plant productivity. The rate of nitrogen addition was similar to published rates of atmospheric nitrogen deposition in urban areas adjacent to the Mojave Desert (3·2 g N m−2 year−1). The dominant alien species included the grasses Bromus madritensis ssp. rubens and Schismus spp. (S. arabicus and S. barbatus) and the forb Erodium cicutarium.4. Soil nitrogen addition increased the density and biomass of alien annual plants during both years, but decreased density, biomass and species richness of native species only during the year of highest annual plant productivity. The negative response of natives may have been due to increased competitive stress for soil water and other nutrients caused by the increased productivity of aliens.5. The effects of nitrogen additions were significant at both ends of a natural nutrient gradient, beneath creosote bush Larrea tridentata canopies and in the interspaces between them, although responses varied among

  6. Rocky shores of a major southern African Marine Protected Area are almost free from intertidal invertebrate alien species

    Directory of Open Access Journals (Sweden)

    Hanlie Malherbe

    2014-05-01

    Full Text Available A major threat to marine ecosystems is the establishment and proliferation of invasive alien species. This study addresses gaps in our knowledge regarding marine alien invertebrate species in the Kogelberg Biosphere Reserve (KBR and adjacent Betty’s Bay Marine Protected Area (MPA in the Western Cape of South Africa, together a potentially important area for south-coast marine conservation. Understanding the distribution and geographical expansion of these species is critical for conservation planning. A quantitative systematic survey of the intertidal rocky shore region was undertaken. The mytilid Mediterranean mussel, Mytilus galloprovincialis, and the bryozoan Watersipora subtorquata were the only alien species recorded along the coastline, which included the MPA. The abundance of M. galloprovincialis was significantly higher outside the MPA, and the abundance of W. subtorquata was significantly higher inside the MPA. With only two alien species recorded, the Betty’s Bay MPA and its surroundings support relatively few marine alien species with regards to rocky shore invertebrate biodiversity. Conservation implications: It is important that the Betty’s Bay MPA and its adjacent coastline maintain its current status as an area with relatively few marine alien species. The conservation implications on management require routine surveys of this region to detect early introductions of any additional species.

  7. Family Harmony: An Etiologic Factor in Alienation

    Science.gov (United States)

    Paulson, Morris J.; And Others

    1972-01-01

    Results suggest that recollections of earlier experienced parental attitudes can be retrospective clues of earlier parent-child interaction along the alienation dimension of an Anti-Establishment vs. Establishment philosophy of early child rearing. (Authors/MB)

  8. Black, White, and Brown Adolescent Alienation

    Science.gov (United States)

    Heussenstamm, F. K.; Hoepfner, Ralph

    1972-01-01

    Those demographic characteristics of adolescents that proved to be most highly significant in relationship to alienation are grade point average, parental approval of friends, and solidarity with peers. (Authors)

  9. The alien terrestrial invertebrate fauna of the High Arctic archipelago of Svalbard: potential implications for the native flora and fauna

    Directory of Open Access Journals (Sweden)

    Stephen J. Coulson

    2015-09-01

    Full Text Available Experience from the Antarctic indicates that the establishment of alien species may have significant negative effects on native flora and fauna in polar regions and is considered to be amongst the greatest threats to biodiversity. But, there have been few similar studies from the Arctic. Although the terrestrial invertebrate inventory of the Svalbard Archipelago is amongst the most complete for any region of the Arctic, no consideration has yet been made of alien terrestrial invertebrate species, their invasiveness tendencies, threat to the native biology or their route of entry. Such baseline information is critical for appropriate management strategies. Fifteen alien invertebrate species have established in the Svalbard environment, many of which have been introduced via imported soils. Biosecurity legislation now prohibits such activities. None of the recorded established aliens yet show invasive tendencies but some may have locally negative effects. Ten species are considered to be vagrants and a further seven are classified as observations. Vagrants and the observations are not believed to be able to establish in the current tundra environment. The high connectivity of Svalbard has facilitated natural dispersal processes and may explain why few alien species are recorded compared to isolated islands in the maritime Antarctic. The vagrant species observed are conspicuous Lepidoptera, implying that less evident vagrant species are also arriving regularly. Projected climate change may enable vagrant species to establish, with results that are difficult to foresee.

  10. Alien Marine Species in the Mediterranean - the 100 ‘Worst Invasives’ and their Impact

    Directory of Open Access Journals (Sweden)

    N. STREFTARIS

    2006-06-01

    Full Text Available A number of marine alien species have been described as invasive or locally invasive in the Mediterranean because of their proliferation, and/or their geographical spread and/or impact on native populations. Based on that information and on the documented impact they have on the biodiversity and socioeconomics of the basin, a preliminary list of the 100 ‘worst’ Invasive Alien Species (IAS in the Mediterranean has been produced and presented in this work along with details on their impact. Emphasis is given to their impact on socioeconomics (fi sheries/aquaculture, health & sanitation, infrastructure & building, documented for 43 species. Such selection of the ‘worst’ IAS was diffi cult and controversial and is expected to attract much attention and scientifi c criticism since not only can the documentation of the impact of IAS be controversial, but also their inventory can be biased towards the effort and resources devoted to the study of the impact of certain species/taxonomic groups. Thus, while marine plants (phytobenthos and phytoplankton are fairly well studied, less attention has been paid to the impact of vertebrates and even less to invertebrates. Nevertheless, the list highlights the need for continued research on the issue (monitoring aliens and their impact for an integrated ecosystem based management approach over the entire area. The preliminary list can provide the basis for selecting indicator species within the Mediterranean and thus be the common ground to build cooperation about IAS within countries in the region.

  11. Alienation and anxiety in tourism motivation

    OpenAIRE

    Vidon, Elizabeth S.; Rickly, Jillian M.

    2018-01-01

    Although underexplored in tourism studies, recent work suggests theories of alienation, as the dialectic of authenticity, have much to contribute to our understanding of tourism motivation. This paper uses three major theoretical tropes (Marxism, existentialism, and Lacanian psychoanalysis) to examine the role of alienation in the motivations of hiking and rock climbing tourists. In particular, these tourists describe only temporary and retrospective relief from anxiety, articulating authenti...

  12. Will climate change promote future invasions?

    Science.gov (United States)

    Bellard, Celine; Thuiller, Wilfried; Leroy, Boris; Genovesi, Piero; Bakkenes, Michel; Courchamp, Franck

    2013-12-01

    Biological invasion is increasingly recognized as one of the greatest threats to biodiversity. Using ensemble forecasts from species distribution models to project future suitable areas of the 100 of the world's worst invasive species defined by the International Union for the Conservation of Nature, we show that both climate and land use changes will likely cause drastic species range shifts. Looking at potential spatial aggregation of invasive species, we identify three future hotspots of invasion in Europe, northeastern North America, and Oceania. We also emphasize that some regions could lose a significant number of invasive alien species, creating opportunities for ecosystem restoration. From the list of 100, scenarios of potential range distributions show a consistent shrinking for invasive amphibians and birds, while for aquatic and terrestrial invertebrates distributions are projected to substantially increase in most cases. Given the harmful impacts these invasive species currently have on ecosystems, these species will likely dramatically influence the future of biodiversity. © 2013 John Wiley & Sons Ltd.

  13. Alien species on the coasts of Turkey

    Directory of Open Access Journals (Sweden)

    M.E. CINAR

    2005-12-01

    Full Text Available The compilation of data on alien species reported from the Turkish coasts yielded a total of 263 species belonging to 11 systematic groups, of which Mollusca had the highest number of species (85 species, followed by Crustacea (51, fishes (43 and phytobenthos (39. The Black Sea is represented by a total of 20 alien species, the Sea of Marmara by 48 species, the Aegean Sea by 98 species and the Levantine Sea by 202 species. The majority of aliens found in the Black Sea and the Sea of Marmara were transported via shipping, whereas the Levantine coast is extensively subjected to Lessepsian migration. Benthic habitats (soft and hard substrata comprise 76% of the total alien species and the pelagic environment is inhabited by thirty-nine species. Almost 50% of aliens collected from the Turkish coasts were found only at 0-10 m depth. Eight species occur at depths deeper than 100 m. The impacts of aliens on the benthic and pelagic ecosystems are presented.

  14. Impact of invasive plants on food webs and pathways

    OpenAIRE

    Sikai Wang; Qiang Sheng; Tianjiang Chu; Bo Li; Jiakuan Chen; Jihua Wu

    2013-01-01

    In natural ecosystems, energy mainly flows along food chains in food webs. Numerous studies have shown that plant invasions influence ecosystem functions through altering food webs. In recent decades, more attention has been paid to the effects of alien plants on local food webs. In this review, we analyze the influence of exotic plants on food webs and pathways, and explore the impacts of local food web characteristics on community invasibility. Invasive plants alter food webs mainly by chan...

  15. The mechanism of PTFE and PE friction deposition: a combined scanning electron and scanning force microscopy study on highly oriented polymeric sliders

    NARCIS (Netherlands)

    Schönherr, Holger; Schaeben, H.; Vancso, Gyula J.

    1998-01-01

    The mechanism of friction deposition of polytetrafluoroethylene (PTFE) and polyethylene (PE) was studied by scanning electron (SEM) and scanning force microscopy (SFM) on the worn surfaces of PTFE and PE sliders that were used in friction deposition on glass substrates. These surfaces exhibited a

  16. Parental Alienation Syndrome vs. Parental Alienation: Which Diagnosis Should Evaluators Use in Child-Custody Disputes?

    Science.gov (United States)

    Gardner, Richard A.

    2002-01-01

    The purpose of this article is to elucidate the sources of controversy between the use of the terms Parental Alienation Syndrome and Parental Alienation and to delineate the advantages and disadvantages of using either term in the context of child-custody disputes. It concludes that families are best served when the more specific term, Parental…

  17. Alien abduction: a medical hypothesis.

    Science.gov (United States)

    Forrest, David V

    2008-01-01

    In response to a new psychological study of persons who believe they have been abducted by space aliens that found that sleep paralysis, a history of being hypnotized, and preoccupation with the paranormal and extraterrestrial were predisposing experiences, I noted that many of the frequently reported particulars of the abduction experience bear more than a passing resemblance to medical-surgical procedures and propose that experience with these may also be contributory. There is the altered state of consciousness, uniformly colored figures with prominent eyes, in a high-tech room under a round bright saucerlike object; there is nakedness, pain and a loss of control while the body's boundaries are being probed; and yet the figures are thought benevolent. No medical-surgical history was apparently taken in the above mentioned study, but psychological laboratory work evaluated false memory formation. I discuss problems in assessing intraoperative awareness and ways in which the medical hypothesis could be elaborated and tested. If physicians are causing this syndrome in a percentage of patients, we should know about it; and persons who feel they have been abducted should be encouraged to inform their surgeons and anesthesiologists without challenging their beliefs.

  18. Simulating plant invasion dynamics in mountain ecosystems under global change scenarios.

    Science.gov (United States)

    Carboni, Marta; Guéguen, Maya; Barros, Ceres; Georges, Damien; Boulangeat, Isabelle; Douzet, Rolland; Dullinger, Stefan; Klonner, Guenther; van Kleunen, Mark; Essl, Franz; Bossdorf, Oliver; Haeuser, Emily; Talluto, Matthew V; Moser, Dietmar; Block, Svenja; Conti, Luisa; Dullinger, Iwona; Münkemüller, Tamara; Thuiller, Wilfried

    2018-01-01

    Across the globe, invasive alien species cause severe environmental changes, altering species composition and ecosystem functions. So far, mountain areas have mostly been spared from large-scale invasions. However, climate change, land-use abandonment, the development of tourism and the increasing ornamental trade will weaken the barriers to invasions in these systems. Understanding how alien species will react and how native communities will influence their success is thus of prime importance in a management perspective. Here, we used a spatially and temporally explicit simulation model to forecast invasion risks in a protected mountain area in the French Alps under future conditions. We combined scenarios of climate change, land-use abandonment and tourism-linked increases in propagule pressure to test if the spread of alien species in the region will increase in the future. We modelled already naturalized alien species and new ornamental plants, accounting for interactions among global change components, and also competition with the native vegetation. Our results show that propagule pressure and climate change will interact to increase overall species richness of both naturalized aliens and new ornamentals, as well as their upper elevational limits and regional range-sizes. Under climate change, woody aliens are predicted to more than double in range-size and herbaceous species to occupy up to 20% of the park area. In contrast, land-use abandonment will open new invasion opportunities for woody aliens, but decrease invasion probability for naturalized and ornamental alien herbs as a consequence of colonization by native trees. This emphasizes the importance of interactions with the native vegetation either for facilitating or potentially for curbing invasions. Overall, our work highlights an additional and previously underestimated threat for the fragile mountain flora of the Alps already facing climate changes, land-use transformations and overexploitation by

  19. Better management of alien species

    Czech Academy of Sciences Publication Activity Database

    Pergl, Jan; Genovesi, P.; Pyšek, Petr

    2016-01-01

    Roč. 531, č. 7593 (2016), s. 173-173 ISSN 0028-0836 Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : invasions * EU * policy Subject RIV: EH - Ecology, Behaviour Impact factor: 40.137, year: 2016

  20. A conceptual framework for invasion in microbial communities

    KAUST Repository

    Kinnunen, Marta

    2016-05-03

    There is a growing interest in controlling-promoting or avoiding-the invasion of microbial communities by new community members. Resource availability and community structure have been reported as determinants of invasion success. However, most invasion studies do not adhere to a coherent and consistent terminology nor always include rigorous interpretations of the processes behind invasion. Therefore, we suggest that a consistent set of definitions and a rigorous conceptual framework are needed. We define invasion in a microbial community as the establishment of an alien microbial type in a resident community and argue how simple criteria to define aliens, residents, and alien establishment can be applied for a wide variety of communities. In addition, we suggest an adoption of the community ecology framework advanced by Vellend (2010) to clarify potential determinants of invasion. This framework identifies four fundamental processes that control community dynamics: dispersal, selection, drift and diversification. While selection has received ample attention in microbial community invasion research, the three other processes are often overlooked. Here, we elaborate on the relevance of all four processes and conclude that invasion experiments should be designed to elucidate the role of dispersal, drift and diversification, in order to obtain a complete picture of invasion as a community process.

  1. ALien Biotic IndEX (ALEX) - a new index for assessing impacts of alien species on benthic communities.

    Science.gov (United States)

    Çinar, Melih Ertan; Bakir, Kerem

    2014-10-15

    Biotic indices are mainly aimed at assessing levels of deterioration caused by chemical or organic pollution. However, no biotic index to date has been developed to detect impacts of alien species on benthic communities. In this paper, a new biotic index, namely ALEX, is proposed to address the objectives of the Water Framework Directive and was tested in Mersin Bay (Levantine Sea, Turkey). Species were divided into four biogeographic groups, namely native species, casual species, established species and invasive species, and the metric considers the relative importance of these groups in samples. The index classified the ecological status of some stations which are shallow, and close to harbor and river mouths as bad or poor in February and October. The ALEX values were positively and significantly correlated with total nitrogen, silicate and silt percentage in sediment, and negatively correlated with depth and the distance from the harbor. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Alien plants in urban nature reserves: from red-list species to future invaders?

    Directory of Open Access Journals (Sweden)

    Vojtěch Jarošik

    2011-10-01

    Full Text Available Urban reserves, as other protected areas, are aimed at preserving species richness but the conservation effort in these protected areas is complicated by a high proportion of alien species. We examined which environmental factors determine the representation of alien species in 48 city reserves of Prague, Czech Republic, distinguishing between archaeophytes, i.e. alien species introduced since the beginning of Neolithic agriculture up to 1500 A. D., and neophytes, i.e. modern invaders introduced after that date, with the former group separately analysed for endangered archaeophytes (listed as C1 and C2 categories on national red list. Archaeophytes responded positively to the extent of arable land that was in place at the time of the reserve establishment, and to a low altitudinal range. Neophytes, beside soil properties responded to recent human activities proxied by current proportion of built-up area in the reserves. Endangered archaeophytes, besides the same affinity for past arable land as other archaeophytes, were supported by the presence of current wasteland habitats in the reserve. This suggests that for endangered archaeophytes it might have been difficult to adapt to changing agricultural practices, and ruderal wasteland might act as a refugium for them. From the viewpoint of conservation, ruderal habitats of nature reserves thus can be more important than was previously though. Forty-six of the 155 neophytes recorded in the reserves are classified as invasive. The reserves thus harbour 67% of the 69 invasive neophytes recorded in the country, and particularly warning is that among the most invasive species are many shrubs and trees, a life form that is known to account for widespread invasions with high impacts. Our results thus strongly suggest that in Prague nature reserves there is a warning potential for future invasions.

  3. Understanding the biological invasion risk posed by the global wildlife trade: propagule pressure drives the introduction and establishment of Nearctic turtles.

    Science.gov (United States)

    García-Díaz, Pablo; Ross, Joshua V; Ayres, César; Cassey, Phillip

    2015-03-01

    Biological invasions are a key component of human-induced global change. The continuing increase in global wildlife trade has raised concerns about the parallel increase in the number of new invasive species. However, the factors that link the wildlife trade to the biological invasion process are still poorly understood. Moreover, there are analytical challenges in researching the role of global wildlife trade in biological invasions, particularly issues related to the under-reporting of introduced and established populations in areas with reduced sampling effort. In this work, we use high-quality data on the international trade in Nearctic turtles (1999-2009) coupled with a statistical modelling framework, which explicitly accounts for detection, to investigate the factors that influence the introduction (release, or escape into the wild) of globally traded Nearctic turtles and the establishment success (self-sustaining exotic populations) of slider turtles (Trachemys scripta), the most frequently traded turtle species. We found that the introduction of a species was influenced by the total number of turtles exported to a jurisdiction and the age at maturity of the species, while the establishment success of slider turtles was best associated with the propagule number (number of release events), and the number of native turtles in the jurisdiction of introduction. These results indicate both a direct and indirect association between the wildlife trade and the introduction of turtles and establishment success of slider turtles, respectively. Our results highlight the existence of gaps in the number of globally recorded introduction events and established populations of slider turtles, although the expected bias is low. We emphasize the importance of researching independently the factors that affect the different stages of the invasion pathway. Critically, we observe that the number of traded individuals might not always be an adequate proxy for propagule pressure

  4. Transferring alien genes to wheat

    International Nuclear Information System (INIS)

    Knott, D.R.

    1987-01-01

    In broad terms an alien gene can be considered to be any gene transferred to wheat from a related species. As described above by Maan (section 7D) the genus Triticum contains a broad range of species, some of which cross readily with the cultivated tetraploid (T. Turgidum L.) or hexaploid (T. aestivum L.) wheats, and others only with great difficulty. In addition, wheat will also cross with species in a number of other genera including Agropyron, Elymus, Elytrigia (=Agropyron), Haynaldia, Hordeum, and Secale (Riley and Kimber, 1966; Knobloch, 1968; Feldman and Sears, 1981). In discussing the Triticum and Aegilops spp., the classification by Kimber and Sears, section SA-I, above, will be followed. For the Agropyron and related species the classification described by Dewey (1983) will be used. To avoid confusion, in referring to the literature the designations used by the authors will be given, followed by the new designation. The wild relatives of wheat are adapted to a broad range of environments and carry a large reservoir of useful genes (Zohary et al., 1969; Kerber and Dyck, 1973; Brezhnev, 1977; Feldman and Sears, 1981; Limin and Fowler, 1981; Sharma et aI., 1981; McGuire and Dvorak, 1981). Initially they were considered to be primarily sources of disease resistance, but more recently they have been recognized as potential sources of genes for high protein, cold tolerance, salt tolerance, drought tolerance, lodging resistance, early maturity, and even yield. Extensive screening of the wild relatives of wheat needs to be done before their useful genes can be fully utilized

  5. The search for alien life

    Science.gov (United States)

    Meyer, M.

    Life on Earth relies exclusively on the complex coordination among DNA, RNA, proteins, and an encompassing cell membrane. This level of complexity has been amenable to new molecular techniques with extreme specificity and sensitivity, enabling spectacular advances in cell biology and microbial ecology. Armed with molecular techniques, the last few decades of research have revealed the surprising extent of life on our own planet, expanding the habitable range of salinity, pressure, temperature, and radiation of our world. Given the relatively recent discoveries about life on Earth, how then can we expect to look for alien life that may use completely different sets of molecules for structure and activity? Astrobiology has taken on the challenge of developing the intellectual basis, target identification, instrument capabilities, and operational procedures for the search for life elsewhere. The research aims to develop general principles of how life maintains itself, how life interacts with its environment, and how the signatures of life may be preserved and recognized. The approach has been to move from the laboratory, to the environment, to robotic exploration of planetary analogs. To date, generic evidence for life can be perceived through life's creation and utilization of disequilibria, multiple uses of a relatively few sets of molecules, a preference for chiral compounds, and a predilection for lighter isotopes. It is through application of life detection instrumentation in environmental extremes that we hope to develop a catalogue of generic biosignatures, robust instrumentation capable of revealing the unexpected, and effective exploration strategies for robotic platforms in the search for signs of life. In 2009, Mars Science Laboratory and ExoMars may be the first beneficiaries of this approach.

  6. The economics of landscape restoration: Benefits of controlling bush encroachment and invasive plant species in South Africa and Namibia

    CSIR Research Space (South Africa)

    Stafford, William

    2017-01-01

    Full Text Available Bush encroachment and alien plant invasions alter the composition and/or balance of species in natural ecosystems and impact biodiversity, land productivity and water availability. Therefore, the appropriate control and management of bush...

  7. An introduction to parental alienation syndrome.

    Science.gov (United States)

    Farkas, Michelle M

    2011-04-01

    Parental alienation syndrome (PAS) can occur during a tumultuous divorce between embattled parents involved in a bitter child custody dispute. During parental warfare, a child is used as a weapon by one parent (alienating parent) against the other parent (alienated/targeted parent). The targeted parent-child relationship once encased with unconditional love is transformed by an unrelenting campaign of denigration, criticism, and hatred. Since nursing literature on PAS is almost nonexistent, the purpose of this article is to increase nursing awareness and provide basic information. Awareness of PAS symptoms and interpersonal dynamics is important to prompt nurses in recommending treatment for families. Nurses should collaboratively join other professionals in their quest to provide the best treatment possible. Copyright 2011, SLACK Incorporated.

  8. Alien roadside species more easily invade alpine than lowland plant communities in a subarctic mountain ecosystem.

    Directory of Open Access Journals (Sweden)

    Jonas J Lembrechts

    Full Text Available Effects of roads on plant communities are not well known in cold-climate mountain ecosystems, where road building and development are expected to increase in future decades. Knowledge of the sensitivity of mountain plant communities to disturbance by roads is however important for future conservation purposes. We investigate the effects of roads on species richness and composition, including the plant strategies that are most affected, along three elevational gradients in a subarctic mountain ecosystem. We also examine whether mountain roads promote the introduction and invasion of alien plant species from the lowlands to the alpine zone. Observations of plant community composition were made together with abiotic, biotic and anthropogenic factors in 60 T-shaped transects. Alpine plant communities reacted differently to road disturbances than their lowland counterparts. On high elevations, the roadside species composition was more similar to that of the local natural communities. Less competitive and ruderal species were present at high compared with lower elevation roadsides. While the effects of roads thus seem to be mitigated in the alpine environment for plant species in general, mountain plant communities are more invasible than lowland communities. More precisely, relatively more alien species present in the roadside were found to invade into the surrounding natural community at high compared to low elevations. We conclude that effects of roads and introduction of alien species in lowlands cannot simply be extrapolated to the alpine and subarctic environment.

  9. Do abundance and proximity of the alien Impatiens glandulifera affect pollination and reproductive success of two sympatric co-flowering native species?

    Directory of Open Access Journals (Sweden)

    Anne-Laure Jacquemart

    2012-12-01

    Full Text Available In invasion ecology, potential impacts of aliens on native flora are still under debate. Our aim was to determine the pollinator mediated effects of both proximity and abundance of an alien species on the reproductive success of natives. We chose the highly invasive Impatiens glandulifera and two native species: Epilobium angustifolium and Aconitum napellus ssp. lusitanicum. These species share characteristics allowing for pollination interactions: similar biotopes, overlapping flowering periods and same main pollinators. The effects of abundance (5, 25 and 100 individuals and proximity (0 and 15 m of the alien on visitation rate, insect behaviour, pollen deposition and reproductive success of both natives were investigated during 2 flowering seasons. We used centred visitation rates as they can be directly interpreted as a positive or negative effect of the invasive.Both abundance and proximity of the alien increased bumblebee visitation rates to both natives. On the other hand, abundance of the exotic species had a slight negative effect on honeybee visits to natives while its proximity had no effect. The behaviour of bumblebees changed as visitors left significantly more often the native plants for I. glandulifera when its abundance increased. As a consequence of this “inconstancy”, bees deposited considerable quantities of alien pollen on native stigmas. Nevertheless, this interspecific pollen transfer did not decrease seed set in natives. Self-compatibility and high attractiveness of both native species probably alleviate the risk of altered pollinator services and reproductive success due to the invader in natural populations.

  10. Updated review of marine alien species and other ‘newcomers’ recorded from the Maltese Islands (Central Mediterranean

    Directory of Open Access Journals (Sweden)

    J. EVANS

    2015-03-01

    Full Text Available An updated review of marine alien species and other ‘newcomers’ recorded from the Maltese Islands is presented on account of new records and amendments to a previous review in 2007. Species were classified according to their establishment status (‘Questionable’, ‘Casual’, ‘Established’, ‘Invasive’ and origin (‘Alien’, ‘Range expansion’, ‘Cryptogenic’. A total of 31 species were added to the inventory, while 6 species have been removed, bringing the total number of species to 73. Of these, 66 are considered to be aliens (or putative aliens but with uncertain origin with the remaining 7 resulting from range expansion. Six records are considered to be questionable and hence unverified. For verified records, the dominant taxonomic groups are Mollusca (represented by 21 species and Actinopterygii (15 species, followed by Crustacea (8 species and Rhodophyta (7 species. Eight of these species (aliens: Caulerpa cylindracea, Lophocladia lallemandi, Womersleyella setacea, Brachidontes pharaonis, Percnon gibbesi, Fistularia commersonii, Siganus luridus; range extender: Sphoeroides pachygaster are considered to be invasive. The introduction pathway for 30 species is unknown. Amongst the alien species, ‘Shipping’ is the most common introduction pathway, followed by ‘Secondary dispersal’ from elsewhere in the Mediterranean Sea. An increasing trend in the number of alien marine species reported from the Maltese Islands is evident, with a peak of 22 species recorded during the last decade (2001–2010. A discussion on the rationale for including range-expanding species in national inventories of recent arrivals, and in the analysis of trends in records from the Maltese Islands, is included. In particular, the general warming trend of Mediterranean surface waters appears to be facilitating the westward spread of thermophilic alien species from the Eastern to the Central Mediterranean, and the eastward range expansion of

  11. AliEn - EDG Interoperability in ALICE

    OpenAIRE

    Bagnasco, S.; Barbera, R.; Buncic, P.; Carminati, F.; Cerello, P.; Saiz, P.

    2003-01-01

    AliEn (ALICE Environment) is a GRID-like system for large scale job submission and distributed data management developed and used in the context of ALICE, the CERN LHC heavy-ion experiment. With the aim of exploiting upcoming Grid resources to run AliEn-managed jobs and store the produced data, the problem of AliEn-EDG interoperability was addressed and an in-terface was designed. One or more EDG (European Data Grid) User Interface machines run the AliEn software suite (Cluster Monitor, Stora...

  12. 45 CFR 233.51 - Eligibility of sponsored aliens.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Eligibility of sponsored aliens. 233.51 Section... CONDITIONS OF ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.51 Eligibility of sponsored aliens... affidavit(s) of support or similar agreement on behalf of an alien (who is not the child of the sponsor or...

  13. 20 CFR 404.1036 - Certain nonresident aliens.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Certain nonresident aliens. 404.1036 Section... Employment § 404.1036 Certain nonresident aliens. (a) Foreign students. (1) Foreign students (nonimmigrant aliens) may be temporarily in the United States under subparagraph (F) of section 101(a)(15) of the...

  14. 43 CFR 426.8 - Nonresident aliens and foreign entities.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Nonresident aliens and foreign entities..., DEPARTMENT OF THE INTERIOR ACREAGE LIMITATION RULES AND REGULATIONS § 426.8 Nonresident aliens and foreign... reclamation law or these regulations, a nonresident alien or foreign entity that directly holds land in a...

  15. 22 CFR 41.58 - Aliens in religious occupations.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Aliens in religious occupations. 41.58 Section... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.58 Aliens in religious occupations. (a) Requirements for “R” classification. An alien shall be classifiable under the provisions of INA...

  16. 22 CFR 40.9 - Classes of inadmissible aliens.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Classes of inadmissible aliens. 40.9 Section 40.9 Foreign Relations DEPARTMENT OF STATE VISAS REGULATIONS PERTAINING TO BOTH NONIMMIGRANTS AND... inadmissible aliens. Subparts B through L describe classes of inadmissible aliens who are ineligible to receive...

  17. 32 CFR 1630.46 - Class 4-T: Treaty alien.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Class 4-T: Treaty alien. 1630.46 Section 1630.46 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM CLASSIFICATION RULES § 1630.46 Class 4-T: Treaty alien. In Class 4-T shall be placed any registrant who is an alien who...

  18. 26 CFR 301.7701(b)-1 - Resident alien.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Resident alien. 301.7701(b)-1 Section 301.7701... ADMINISTRATION PROCEDURE AND ADMINISTRATION Definitions § 301.7701(b)-1 Resident alien. (a) Scope. Section 301.7701(b)-1(b) provides rules for determining whether an alien individual is a lawful permanent resident...

  19. 42 CFR 436.128 - Coverage for certain qualified aliens.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Coverage for certain qualified aliens. 436.128... Mandatory Coverage of the Categorically Needy § 436.128 Coverage for certain qualified aliens. The agency... § 440.255(c) of this chapter to those aliens described in § 436.406(c) of this subpart. [55 FR 36820...

  20. 42 CFR 435.350 - Coverage for certain aliens.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Coverage for certain aliens. 435.350 Section 435... ISLANDS, AND AMERICAN SAMOA Optional Coverage of the Medically Needy § 435.350 Coverage for certain aliens... treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those aliens...

  1. 22 CFR 41.24 - International organization aliens.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false International organization aliens. 41.24... aliens. (a) Definition of international organization. “International organization” means: (1) Any public...)(27)(I), INTELSAT or any successor or separated entity thereof. (b) Aliens coming to international...

  2. 32 CFR 1602.3 - Aliens and nationals.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Aliens and nationals. 1602.3 Section 1602.3 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.3 Aliens and nationals. (a) The term alien means any person who is not a citizen or national of the...

  3. 22 CFR 41.55 - Aliens with extraordinary ability.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Aliens with extraordinary ability. 41.55... IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.55 Aliens with extraordinary ability. (a) Requirements for O classification. An alien shall be classifiable under the provisions of INA 101...

  4. The Lost Parents' Perspective on Parental Alienation Syndrome.

    Science.gov (United States)

    Vassiliou, Despina; Cartwright, Glenn F.

    2001-01-01

    Examined alienated fathers' and mothers' perceptions of parental alienation syndrome (PAS). Data were collected via semistructured, open ended interview questionnaires to determine if there were shared characteristics among alienated families; common issues in marital conflicts contributing to marriage dissolution; similarities in experience of…

  5. Implementing invasive species management in an adaptive management framework

    Directory of Open Access Journals (Sweden)

    Llewellyn C. Foxcroft

    2011-05-01

    Full Text Available Adaptive management theory has attracted substantial interest in recent years, in natural resource management in general and also for invasive alien species management. However, whilst many theoretical and conceptual advances have been made, documented cases of practical applications are rare. Coupling invasive species management components with adaptive feedback processes is not without challenges, requiring a substantial change in the thinking and practice of all those involved. Drawing on a decade of experience in South African National Parks, we suggest an approach to implementing adaptive management for controlling invasive alien species. Whilst efforts have been made to advance components of the overall management strategy, the absence of a framework for decision making and feedback mechanisms, inflexibility in the system and shortcomings in the governance structure are all identified as barriers to learning and knowledge integration for the purposes of effective invasive alien species management. The framework provided here, encompassing documents, committees and processes, is aimed at addressing these shortcomings.Conservation implication: Adaptive management theory offers a robust tool for managing inherently complex systems. Its practical application, however, requires distilling the theory into useable functions. We offer a framework to advance implementation of strategic adaptive management for the control of invasive alien species using experiences gained from South African National Parks.

  6. Alien Insect Impact on Cultural Heritage and Landscape: an Underestimated Problem

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    Barbara Manachini

    2017-06-01

    Full Text Available The impact of alien invasive insects on cultural heritage and landscapes is very often neglected; even though, more than 50% of species that threaten cultural heritage in Europe are of exotic origin. In addition they are more aggressive. Several examples and a description, are given of the most dangerous alien insects present in heritage sites that constitute a risk for the conservation of cultural property: museum collections, libraries, archives and historic buildings. Globalisation has increased this phenomenon but traces of the accidental introduction of insect pests have occurred since Roman times. The paper discusses the need to implement an estimation of the costs that arise from the damage caused by these species and the lack of specific legislative aspects.

  7. Guppies (Poecilia reticulata) introducing an alien parasite, Camallanus cotti (Nematoda: Camallanidae) to Africa, the first report.

    Science.gov (United States)

    Tavakol, Sareh; Halajian, Ali; Smit, Willem J; Hoffman, Andre; Luus-Powell, Wilmien J

    2017-12-01

    Introduced alien fish species and their associated parasites may result in a serious threat to indigenous biodiversity. Furthermore, this may have negative impacts on cultured fish as well as on native parasitic fauna. In the present study, the invasive Asian nematode, Camallanus cotti Fujita, 1927 (Nematoda: Camallanidae), is reported from the guppy (Poecilia reticulata) for the first time in Africa. This parasite is assumed to be introduced into Africa along with the introduction of exotic poeciliid fishes, which are known to be the most common hosts of C. cotti in ornamental fish industry worldwide.The presence of this parasite in both aquarium-cultured fish as well as fish from natural waterbodies is evidence of the introduction of the alien organisms due to insufficient prophylactic veterinary control during transfer of non-native hosts between countries and the spread of them by the anthropogenic introduction to natural systems.

  8. Foliar mono- and sesquiterpene contents in relation to leaf economic spectrum in native and alien species in Oahu (Hawai'i).

    Science.gov (United States)

    Sardans, Jordi; Llusià, Joan; Niinemets, Ulo; Owen, Sue; Peñuelas, Josep

    2010-02-01

    Capacity for terpene production may confer advantage in protection against abiotic stresses such as heat and drought, and also against herbivore and pathogen attack. Plant invasive success has been intense in the Hawaiian islands, but little is known about terpene content in native and alien plant species on these islands. We conducted a screening of leaf terpene concentrations in 35 native and 38 alien dominant plant species on Oahu island. Ten (29%) of the 35 native species and 15 (39%) of the 38 alien species contained terpenes in the leaves. This is the first report of terpene content for the ten native species, and for 10 of the 15 alien species. A total of 156 different terpenes (54 monoterpenes and 102 sesquiterpenes) were detected. Terpene content had no phylogenetic significance among the studied species. Alien species contained significantly more terpenes in leaves (average+/-SE=1965+/-367 microg g(-1)) than native species (830+/-227 microg g(-1)). Alien species showed significantly higher photosynthetic capacity, N content, and lower Leaf Mass Area (LMA) than native species, and showed higher total terpene leaf content per N and P leaf content. Alien species, thus, did not follow the expected pattern of "excess carbon" in comparison with native species. Instead, patterns were consistent with the "nutrient driven synthesis" hypothesis. Comparing alien and native species, the results also support the modified Evolution of Increased Competitive Ability (EICA) hypothesis that suggests that alien success may be favored by a defense system based on an increase in concentrations of less costly defenses (terpenes) against generalist herbivores.

  9. Does residence time affect responses of alien species richness to environmental and spatial processes?

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    Matteo Dainese

    2012-08-01

    Full Text Available One of the most robust emerging generalisations in invasion biology is that the probability of invasion increases with the time since introduction (residence time. We analysed the spatial distribution of alien vascular plant species in a region of north-eastern Italy to understand the influence of residence time on patterns of alien species richness. Neophytes were grouped according to three periods of arrival in the study region (1500–1800, 1800–1900, and > 1900. We applied multiple regression (spatial and non-spatial with hierarchical partitioning to determine the influence of climate and human pressure on species richness within the groups. We also applied variation partitioning to evaluate the relative importance of environmental and spatial processes. Temperature mainly influenced groups with speciesa longer residence time, while human pressure influenced the more recently introduced species, although its influence remained significant in all groups. Partial regression analyses showed that most of the variation explained by the models is attributable to spatially structured environmental variation, while environment and space had small independent effects. However, effects independent of environment decreased, and spatially independent effects increased, from older to the more recent neophytes. Our data illustrate that the distribution of alien species richness for species that arrived recently is related to propagule pressure, availability of novel niches created by human activity, and neutral-based (dispersal limitation processes, while climate filtering plays a key role in the distribution of species that arrived earlier. This study highlights the importance of residence time, spatial structure, and environmental conditions in the patterns of alien species richness and for a better understanding of its geographical variation.

  10. alien city. Grad u toku / alien city. The City In Progress

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    Marta Smolińska

    2012-12-01

    the threshold of the city. alien city could be compared with the so-called ideal, perfectly laid out cities (for example Sforzinda by Filarete and its dynamic structure could be juxtaposed with a monad, proposed by G.W. Leibnitz. It is processual, unstable, elusive and limitless. As a delocalized and nomadic structure alien city cannot have any stable history — in contrary, it’s history is changeable, indefi nite and, in fact, unpredictable.

  11. Native and alien ichthyofauna in coastal fishery of Rhodes (eastern Mediterranean (2002-2010

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    Maria Corsini-Foka

    2015-11-01

    Full Text Available Rhodes Island (southeastern Aegean is located in a geographically crucial region subjected to biological invasions. Among the 108 alien species recorded, 30 are fish, all of Indo-Pacific/Red Sea origin introduced via Suez through Lessepsian migration (Corsini-Foka et al., 2015; Corsini-Foka and Kondylatos, In press; Kondylatos and Corsini-Foka, In press. In this oligotrophic area, fishery production is limited, due to the paucity of species of commercial interest and their low abundance, while adapted infrastructures for fish landing and marketing are absent. Coastal fishery has dominated during the last twenty years (ELSTAT, 2015. Within 2002-2010, the Hydrobiological Station of Rhodes conducted experimental boat seining surveys, using exclusively a professional 12m fishing boat, at 5-30 m depth, in the Gulf of Trianda (sandy mud, Posidonia meadows. The 94 carried out hauls (7-18 hauls/year, produced a total fish biomass of approximately 4400 Kg, recording 97 fish (86 native, 11 alien and 4 cephalopod species (3 native, 1 alien. Fish species ranged from 32 to 63/year, whereas aliens ranged from 5 to 8 species. Almost steadily present since 2002, were earlier colonizers such as Apogonichthyoides pharaonis, Siganus rivulatus, Siganus luridus, Stephanolepis diaspros and more recent ones as Pteragogus trispilus, Sphyraena chrysotaenia and Fistularia commersonii, while Lagocephalus sceleratus, firstly recorded in 2005, occurred regularly since 2007; the presence of Lagocephalus suezensis, Sphyraena flavicauda and Upeneus pori was scattered since their first records in 2004-2005. Alien fish commercially important are the Siganids, S. chrysotaenia and surprisingly F. commersonii. In terms of biomass per haul, alien fish ranged from 0 to 18.5 Kg, native from 1.5 to 182 Kg. Catches were dominated by Centracanthidae (Spicara spp. and Sparidae (Boops boops, sometimes by other native such as Oblada melanura, Diplodus spp., Chromis Chromis and others. The

  12. The psychosocial treatment of parental alienation.

    Science.gov (United States)

    Darnall, Douglas

    2011-07-01

    Parental alienation occurs in divorces when one parent indoctrinates the child to dislike, fear, and avoid contact with the other parent. Mental health professionals who treat children and adolescents are likely to encounter victims of parental alienation in clinical practice, and it is important to identify and treat these youngsters earlier, when the condition is mild, rather than later, when the parental alienation is almost intractable. This article presents an overview of the treatment of parental alienation, which is called reunification therapy. All the parties involved in the case have a role in the prevention and treatment of parental alienation. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Parental alienation syndrome. A developmental analysis of a vulnerable population.

    Science.gov (United States)

    Price, J L; Pioske, K S

    1994-11-01

    1. Parental alienation syndrome is the systematic denigration by one parent of the other parent with the intent of alienating the child. 2. Parents who engage in alienating activity have experienced loss, leading to depression, anger, and aggression. The family system experiences loss during divorce and is adversely affected by the alienating activities of one parent. 3. Understanding the dynamics of parental alienation syndrome will position the nurse to recognize it as a symptom of depression and dependence, and bring care to the vulnerable population.

  14. Alien wavelength modeling tool and field trial

    DEFF Research Database (Denmark)

    Sambo, N.; Sgambelluri, A.; Secondini, M.

    2015-01-01

    A modeling tool is presented for pre-FEC BER estimation of PM-QPSK alien wavelength signals. A field trial is demonstrated and used as validation of the tool's correctness. A very close correspondence between the performance of the field trial and the one predicted by the modeling tool has been...

  15. The use of alien gene transfers

    International Nuclear Information System (INIS)

    Bhatia, C.R.

    1976-01-01

    The present status of the gene transfers from alien species belonging to the sub-tribe Triticanae into wheat is reviewed, and the advantages and disadvantages of the different methods available for such transfers are examined. In general, the alien genes provide a high degree of resistance against a notably wide range of physiological races of wheat rusts, powdery mildew and other diseases. The alien resistance, like other sources of resistance, is known to break down for certain new races. This may happen more often when alien genes of resistance are widely incorporated in commercial cultivars and grown over large areas. So far, few of the available induced translocation stocks have contributed to the development of agronomically superior commercial cultivars, mainly due to the associated undesirable effects of the translocations on agronomic characters of the recipient variety. The deleterious effects appear in some genetic backgrounds and not in others. Extensive hybridization of translocation stocks with different genotypes has been emphasized by most investigators. Such programmes have led to the release of three commercial cultivars - 2 in Australia and 1 in the USA. On the other hand, spontaneous wheat-rye translocations carrying gene(s) for disease resistance have been unconsciously incorporated into several wheat cultivars, some of them are widely cultivated and were top in ranking based on grain yield. (author)

  16. God-Belief, Self- Detection, Alienation

    Directory of Open Access Journals (Sweden)

    Dr Majid Sadeghi Hasan Abadi

    2010-01-01

    Full Text Available According to some Western thinkers, considering earthy and compelled human alongside with the heavenly and compelling God can result in nothing but human’s alienation and transduction of alien personality in his mind and spirit. Basically, man’s realization of alienation and its type has a close relationship with the way of consideration of human and his nature. Of course type of human regard to God and kind of God that a religion defines, is another altered factor that into the side transaction, human and God has a decisive role. In Islamic teaching human nature and religion are defined as two truth corresponding together and in other words unique truth manifest into the sight of genesis and legislation as human nature and religion. In Islamic philosophy especially Hekmah Al-Motaaliyeh (transcendental wisdom human’s relationship with God and also universe with God, is the same as relation and dependency. In heavenly instructions, human nature is divine whiff. Therefore, it should have total congruity with divine nature. Since self- forgetfulness is the direct result of God- forgetfulness, God-belief and self- detection have strong relation with each other, too. Moreover, in the mystical instructions of the Muslims mystics, God is a truth that is closer to man than himself. And therefore, the more he is such proximity , attraction and rapture to God, not only the man becomes self- alien , but also he will recognize himself better than before and will approach to his own origin.

  17. God-Belief, Self- Detection, Alienation

    Directory of Open Access Journals (Sweden)

    Majid Sadeghi Hasan Abadi

    2010-03-01

    Full Text Available According to some Western thinkers, considering earthy and compelled human alongside with the heavenly and compelling God can result in nothing but human’s alienation and transduction of alien personality in his mind and spirit. Basically, man’s realization of alienation and its type has a close relationship with the way of consideration of human and his nature. Of course type of human regard to God and kind of God that a religion defines, is another altered factor that into the side transaction, human and God has a decisive role. In Islamic teaching human nature and religion are defined as two truth corresponding together and in other words unique truth manifest into the sight of genesis and legislation as human nature and religion. In Islamic philosophy especially Hekmah Al-Motaaliyeh (transcendental wisdom human’s relationship with God and also universe with God, is the same as relation and dependency. In heavenly instructions, human nature is divine whiff. Therefore, it should have total congruity with divine nature. Since self- forgetfulness is the direct result of God- forgetfulness, God-belief and self- detection have strong relation with each other, too. Moreover, in the mystical instructions of the Muslims mystics, God is a truth that is closer to man than himself. And therefore, the more he is such proximity , attraction and rapture to God, not only the man becomes self- alien , but also he will recognize himself better than before and will approach to his own origin.

  18. God-Belief, Self- Detection, Alienation

    Directory of Open Access Journals (Sweden)

    Majid Sadeghi Hasan Abadi

    2010-04-01

    Full Text Available According to some Western thinkers, considering earthy and compelled human alongside with the heavenly and compelling God can result in nothing but human’s alienation and transduction of alien personality in his mind and spirit. Basically, man’s realization of alienation and its type has a close relationship with the way of consideration of human and his nature. Of course type of human regard to God and kind of God that a religion defines, is another altered factor that into the side transaction, human and God has a decisive role. In Islamic teaching human nature and religion are defined as two truth corresponding together and in other words unique truth manifest into the sight of genesis and legislation as human nature and religion. In Islamic philosophy especially Hekmah Al-Motaaliyeh (transcendental wisdom human’s relationship with God and also universe with God, is the same as relation and dependency. In heavenly instructions, human nature is divine whiff. Therefore, it should have total congruity with divine nature. Since self- forgetfulness is the direct result of God- forgetfulness, God-belief and self- detection have strong relation with each other, too. Moreover, in the mystical instructions of the Muslims mystics, God is a truth that is closer to man than himself. And therefore, the more he is such proximity , attraction and rapture to God, not only the man becomes self- alien , but also he will recognize himself better than before and will approach to his own origin.

  19. Alienating identifications and the psychoanalytic process.

    Science.gov (United States)

    Scariati, Giuseppe

    2009-10-01

    The transmission of psychic life from one generation to the next can result in unconscious, alienating identifications when the parents have not been able to elaborate a process of mourning for their own childhoods. In this article, the author describes the nature of these identifications, constructed around insufficiently symbolized experiences, as revealed during the psychoanalytic process. These unconscious, alienating identifications raise some arduous technical problems for the psychoanalyst as they lead the patient to carry out complex enactments that erase the normal transference markers. The psychoanalyst may then be tempted to resort to pejorative theoretical concepts, such as the death drive. And yet, unknown to the analysand, the insufficiently symbolized psychic elements contain a potential for transformation that may lead to reconstructions and dis-alienating interpretations. The author distinguishes between alienating identifications and fantasies of identification when the latter transiently appear during the psychoanalytic process. These identification fantasies symbolically register the emotional experience undergone during the analytic sessions and contribute to the integration of insufficiently symbolized psychic elements. These theoretical considerations are fully illustrated by the clinical report of some analytic sessions.

  20. Notes on Alien Bromus Grasses in Taiwan

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    Ming-Jer Jung

    2006-06-01

    Full Text Available Bromus carinatus Hook. & Arn., Bromus hordeaceus L., Bromus pubescens Muhl. ex Willd. and Bromus secalinus L. were recently found at middle elevations of southern and central Taiwan, respectively. We present taxonomic treatments, distribution map, and line-drawings of these introduced alien brome grasses.