WorldWideScience

Sample records for freshwater invasive alien

  1. Invasive alien birds in Denmark

    DEFF Research Database (Denmark)

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

    2015-01-01

    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......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...... 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...

  2. 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...

  3. 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...... 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...

  4. Assessment and Management of Invasive Alien Predators

    OpenAIRE

    Kirsty Park

    2004-01-01

    Although invasive alien species have been identified as the second greatest threat to biodiversity after habitat loss, characterizing and quantifying their impacts on native species and habitats remains a fundamental problem in conservation biology. Here, I review the techniques that are currently used to assess the impact of invasive alien species on biodiversity, highlighting both their uses in invasive species ecology and their limitations in establishing a causal relationship. Adopting a ...

  5. 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...... 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...

  6. 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

  7. [Alien species invasion in Southern China and its countermeasures].

    Science.gov (United States)

    Fan, Jihui; Li, Jiang; Cheng, Genwei

    2005-03-01

    Alien species invasion may cause serious ecological damage, resulting in ecological crisis and biodiversity comedown, and further menacing existing human environment. At present, the invasion of alien species has brought very serious damage to China's environment and society. The direct annual loss of its agro-forestry industry accounts for 574 billion RMB. Taking the alien species in Southern China as an example, this paper analyzed the bio-invasion approaches, mechanics and damages, and aiming at the characters of invaded area and concerned ecosystems and species, proposed several prevention measurements, i.e., pay attention to the phenomena of bio-invasion and to the basic researches on it; intensify the legislation and establish scientific strategies for introducing alien species; enforce the quarantine on invasive species and establish countrywide monitoring system on alien species; enhance people's defending consciousness; and strengthen international cooperation and collaboration.

  8. 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...... at former shrub margins compared with the center; resprouts were taller and originated from more superficial soil layers at the margin than in the center. Resprouting was negatively correlated with fragment depth, and no resprouts were observed from greater than 15 cm depth. The number of resprouts...... increased with fragment dry mass (0.5–168.5 g). After 18 months with harrowing the species was still resprouting, flowering, and fruiting, albeit with no difference between shrub margin and center. Resprouts were taller (26 cm) and coverage was higher (0–4%) after two compared with three times harrowing...

  9. Modelling Hotspots for Invasive Alien Plants in India.

    Directory of Open Access Journals (Sweden)

    Dibyendu Adhikari

    Full Text Available 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.

  10. 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.

  11. 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.

  12. 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 , including Azolla filiculoides Lam. (Azollaceae), Eichhornia crassipes (C.Mart.) Solms (Pontederiaceae) and Salvinia molesta D.S. Mitch. (Salviniaceae), invade dams, reservoirs and freshwater ecosystems, where they impact nega- tively on water quality...- cessful biological control of Azolla filiculoides in South Africa. Biological Control 28: 25?32. MGOBOZI, M.P., SOMERS, M.J. & DIPPENAAR- SCHOEMAN, A.S. 2008. Spider responses to alien plant invasion: the effect of short- and long-term Chromolaena...

  13. Retrospection of Alien Invasive Forest Insect Pests in China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Eleven species of alien invasive forest insect pests have been found since the early time that insect species had been taken recorded in China. Their origins, inland distribution, invasive time, hosts, causing damage are recorded in this paper for the evidence of biological invasion. Their control methods are also studied or discussed.

  14. 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.

  15. 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...

  16. Invasive alien woody plants of the northern Cape

    Directory of Open Access Journals (Sweden)

    L. Henderson

    1991-12-01

    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.

  17. Alien plant invasions of protected areas in Java, Indonesia.

    Science.gov (United States)

    Padmanaba, Michael; Tomlinson, Kyle W; Hughes, Alice C; Corlett, Richard T

    2017-08-24

    Alien plants are invading protected areas worldwide, but there is little information from tropical Asia. Java has the longest record of human occupation in Asia and today supports 145 m people. Remnants of natural ecosystems survive in 12 small National Parks surrounded by dense human populations, making them highly vulnerable to invasions. We surveyed eight of these, along a rainfall gradient from lowland rainforest with >3000 mm annual rainfall to savanna with <1500 mm, and a 0-3158 m altitudinal gradient, using 403 10 × 5 m plots along trails. We found 67 invasive alien plant species, of which 33 occurred in only one park and two (Chromolaena odorata and Lantana camara) in all. Historical factors relating to plant introduction appeared to be as important as environmental factors in determining which species occurred in which park, while within parks canopy cover and altitude were generally most influential. Spread away from trails was only evident in open habitats, including natural savannas in Baluran National Park, threatened by invasion of Acacia nilotica. Existing control attempts for invasive aliens are reactive, localized, and intermittent, and insufficient resources are currently available for the early detection, prompt action, and continued monitoring that are needed.

  18. Floristic characteristics of alien invasive seed plant species in China

    Directory of Open Access Journals (Sweden)

    CONGYAN WANG

    Full Text Available ABSTRACT This study aims to determine the floristic characteristics of alien invasive seed plant species (AISPS in China. There are a total of five hundred and thirteen AISPS, belonging to seventy families and two hundred and eighty-three genera. Seventy families were classified into nine areal types at the family level, and "Cosmopolitan" and "Pantropic" are the two main types. Two hundred and eighty-three genera were classified into twelve areal types at the genus level, and "Pantropic", "Trop. Asia & Amer. disjuncted", and "Cosmopolitan" are the three main types. These results reveal a certain degree of diversity among AISPS in China. The floristic characteristics at the family level exhibit strong pantropic characteristics. Two possible reasons for this are as follows. Firstly, southeastern China is heavily invaded by alien invasive plant species and this region has a mild climate. Secondly, southeastern China is more disturbed by human activities than other regions in China. The floristic characteristics at the genus level display strong pantropic but with abundant temperate characteristics. This may be due to that China across five climatic zones and the ecosystems in which the most alien invasive plant species occur have the same or similar climate with their natural habitat.

  19. Colossal aggregations of giant alien freshwater fish as a potential biogeochemical hotspot.

    Science.gov (United States)

    Boulêtreau, Stéphanie; Cucherousset, Julien; Villéger, Sébastien; Masson, Rémi; Santoul, Frédéric

    2011-01-01

    The ubiquity and fascinating nature of animal aggregations are widely recognised. We report here consistent and previously undocumented occurences of aggregations of a giant alien freshwater fish, the Wels catfish (Silurus glanis). Aggregative groups were on average composed of 25 (± 10 SD, ranging from 15 to 44) adults with estimated average total biomass of 651 kg (386 - 1132) and biomass density of 23 kg m(-2) (14 - 40). Aggregations always occurred within the same location. No foraging, reproductive or anti-predator behaviour were observed during the aggregations. A mass-balance model estimated that these colossal aggregations of an alien species can locally release, through excretion only, up to 70 mg P m(-2) h(-1) and 400 mg N m(-2) h(-1), potentially representing the highest biogeochemical hotspots reported in freshwater ecosystems and another unexpected ecological effect of alien species.

  20. Colossal aggregations of giant alien freshwater fish as a potential biogeochemical hotspot.

    Directory of Open Access Journals (Sweden)

    Stéphanie Boulêtreau

    Full Text Available The ubiquity and fascinating nature of animal aggregations are widely recognised. We report here consistent and previously undocumented occurences of aggregations of a giant alien freshwater fish, the Wels catfish (Silurus glanis. Aggregative groups were on average composed of 25 (± 10 SD, ranging from 15 to 44 adults with estimated average total biomass of 651 kg (386 - 1132 and biomass density of 23 kg m(-2 (14 - 40. Aggregations always occurred within the same location. No foraging, reproductive or anti-predator behaviour were observed during the aggregations. A mass-balance model estimated that these colossal aggregations of an alien species can locally release, through excretion only, up to 70 mg P m(-2 h(-1 and 400 mg N m(-2 h(-1, potentially representing the highest biogeochemical hotspots reported in freshwater ecosystems and another unexpected ecological effect of alien species.

  1. Climate change vulnerability of native and alien freshwater fishes of California: a systematic assessment approach.

    Directory of Open Access Journals (Sweden)

    Peter B Moyle

    Full Text Available Freshwater fishes are highly vulnerable to human-caused climate change. Because quantitative data on status and trends are unavailable for most fish species, a systematic assessment approach that incorporates expert knowledge was developed to determine status and future vulnerability to climate change of freshwater fishes in California, USA. The method uses expert knowledge, supported by literature reviews of status and biology of the fishes, to score ten metrics for both (1 current status of each species (baseline vulnerability to extinction and (2 likely future impacts of climate change (vulnerability to extinction. Baseline and climate change vulnerability scores were derived for 121 native and 43 alien fish species. The two scores were highly correlated and were concordant among different scorers. Native species had both greater baseline and greater climate change vulnerability than did alien species. Fifty percent of California's native fish fauna was assessed as having critical or high baseline vulnerability to extinction whereas all alien species were classified as being less or least vulnerable. For vulnerability to climate change, 82% of native species were classified as highly vulnerable, compared with only 19% for aliens. Predicted climate change effects on freshwater environments will dramatically change the fish fauna of California. Most native fishes will suffer population declines and become more restricted in their distributions; some will likely be driven to extinction. Fishes requiring cold water (<22°C are particularly likely to go extinct. In contrast, most alien fishes will thrive, with some species increasing in abundance and range. However, a few alien species will likewise be negatively affected through loss of aquatic habitats during severe droughts and physiologically stressful conditions present in most waterways during summer. Our method has high utility for predicting vulnerability to climate change of diverse fish

  2. Invasive alien woody plants of the Orange Free State

    Directory of Open Access Journals (Sweden)

    L. Henderson

    1991-12-01

    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.

  3. Invasive alien woody plants of the Orange Free State

    Directory of Open Access Journals (Sweden)

    L. Henderson

    1991-12-01

    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.

  4. Invasive alien woody plants of the eastern Cape

    Directory of Open Access Journals (Sweden)

    L. Henderson

    1992-12-01

    Full Text Available The frequency and abundance of invasive alien woody plants were recorded along roadsides and at watercourse crossings in 69.9% (151/216 of the quarter degree squares in the study area. The survey yielded 101 species of which the most prominent (in order of prominence in roadside and veld habitats were:  Opuntia ficus-indica, Acacia meamsii and A. cyclops. The most prominent species (in order of prominence in streambank habitats were:  A. meamsii, Populus x  canescens, Salix babylonica and  S. fragilis (fide R.D. Meikle.The greatest intensity of invasion was recorded in the wetter eastern parts and particularly in the vicinity of Port Elizabeth. Uitenhage, East London, Grahamstown, Hogsback and Stutterheim. There was relatively little invasion in the central and western dry interior except along watercourses.

  5. 外来侵袭物种的法律定义%Legal Definition on Alien Invasive Species

    Institute of Scientific and Technical Information of China (English)

    高敏

    2005-01-01

    Agriculture,economy,ecological environment and human health are heavily threatened by alien invasive species ,Alien invasive species is spreading in our country,How to prevent,control and destroy alien invasive species through systems and regulations is problem for related legislation to resolve,However,how to deline alien species,invasive and introduction is premise of legal control on alien invasive species,and determines scope and offect of legal control,through comparing and analyzing legal definition of other countries.legal definition on alien invasive species in our country is put forwarded in the article。

  6. Essential elements of online information networks on invasive alien species

    Science.gov (United States)

    Simpson, A.; Sellers, E.; Grosse, A.; Xie, Y.

    2006-01-01

    In order to be effective, information must be placed in the proper context and organized in a manner that is logical and (preferably) standardized. Recently, invasive alien species (IAS) scientists have begun to create online networks to share their information concerning IAS prevention and control. At a special networking session at the Beijing International Symposium on Biological Invasions, an online Eastern Asia-North American IAS Information Network (EA-NA Network) was proposed. To prepare for the development of this network, and to provide models for other regional collaborations, we compare four examples of global, regional, and national online IAS information networks: the Global Invasive Species Information Network, the Invasives Information Network of the Inter-American Biodiversity Information Network, the Chinese Species Information System, and the Invasive Species Information Node of the US National Biological Information Infrastructure. We conclude that IAS networks require a common goal, dedicated leaders, effective communication, and broad endorsement, in order to obtain sustainable, long-term funding and long-term stability. They need to start small, use the experience of other networks, partner with others, and showcase benefits. Global integration and synergy among invasive species networks will succeed with contributions from both the top-down and the bottom-up. ?? 2006 Springer.

  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. Climate change vulnerability of native and alien freshwater fishes of California: a systematic assessment approach.

    Science.gov (United States)

    Moyle, Peter B; Kiernan, Joseph D; Crain, Patrick K; Quiñones, Rebecca M

    2013-01-01

    Freshwater fishes are highly vulnerable to human-caused climate change. Because quantitative data on status and trends are unavailable for most fish species, a systematic assessment approach that incorporates expert knowledge was developed to determine status and future vulnerability to climate change of freshwater fishes in California, USA. The method uses expert knowledge, supported by literature reviews of status and biology of the fishes, to score ten metrics for both (1) current status of each species (baseline vulnerability to extinction) and (2) likely future impacts of climate change (vulnerability to extinction). Baseline and climate change vulnerability scores were derived for 121 native and 43 alien fish species. The two scores were highly correlated and were concordant among different scorers. Native species had both greater baseline and greater climate change vulnerability than did alien species. Fifty percent of California's native fish fauna was assessed as having critical or high baseline vulnerability to extinction whereas all alien species were classified as being less or least vulnerable. For vulnerability to climate change, 82% of native species were classified as highly vulnerable, compared with only 19% for aliens. Predicted climate change effects on freshwater environments will dramatically change the fish fauna of California. Most native fishes will suffer population declines and become more restricted in their distributions; some will likely be driven to extinction. Fishes requiring cold water (fishes will thrive, with some species increasing in abundance and range. However, a few alien species will likewise be negatively affected through loss of aquatic habitats during severe droughts and physiologically stressful conditions present in most waterways during summer. Our method has high utility for predicting vulnerability to climate change of diverse fish species. It should be useful for setting conservation priorities in many different

  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. 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.

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

    Science.gov (United States)

    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. PMID:26882479

  12. 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...... common and widespread native ladybirds before and after the arrival of Harmonia axyridis, a globally rapidly expanding IAS. Location Europe Methods We used generalized linear mixed-effects models (GLMMs) to assess the distribution trends of eight conspicuous and historically widespread and common species...... surveys of deciduous trees in Belgium, Britain and Switzerland. Results Five (Belgium) and seven (Britain) of eight species studied show substantial declines attributable to the arrival of H. axyridis. Indeed, the two-spot ladybird, Adalia bipunctata, declined by 30% (Belgium) and 44% (Britain) over 5...

  13. 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

    Full Text Available Zimbabwe’s casual, naturalised and invasive alien plant species were analysed with regard to their habit, origin, mode or purpose of introduction and their invasion status in the country. This alien flora of 391 taxa belonged to 239 genera and 73 families, corresponding to 6.6%of the total flora of Zimbabwe. Of these, 153 (39.1% plant species were casual aliens, 154 (39.4% were naturalised and 84 (21.5% were invasive species. Most invasions in terms of numbers of alien species were in the central and eastern parts of the country. Asteraceae (53 species, Poaceae (48 species and Fabaceae sensu lato (49 species families were prominent in all the floristic regions of the country. Annual and perennial herbaceous species formed the majority of life forms of the casual, naturalised and invasive alien flora of Zimbabwe. Genera with the highest number of alien species were Ipomoea with nine species, Acacia and Euphorbiawith eight species each, Chenopodium and Senna with seven species each, Eucalyptus with six species, Oenothera, Physalis and Solanum with five species each. More than 49.6% of the alien plants in Zimbabwe originated primarily from South, Central and North America, followed by Europe (24.6%, Asia (23.8%, Africa (10.5% and Australasia (5.9%. 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.

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

    Directory of Open Access Journals (Sweden)

    Sonia Vanderhoeven

    2017-05-01

    initiatives, including citizen science with a wide taxonomic scope from marine, terrestrial and freshwater environments. Observation data will be funnelled in repeatable ways to GBIF. In parallel, a Belgian checklist of AS will be established, benefiting from various taxonomic and project-based checklists foreseen for GBIF publication. The combination of the observation data and the checklist will feed indicators for the identification of emerging species; their level of invasion in Belgium; changes in their invasion status and the identification of areas and species of concern that could be impacted upon by bioinvasions. Data-driven risk evaluation of identified emerging species will be supported by niche and climate modelling and consequent risk mapping using critical climatic variables for the current and projected future climate periods at high resolution. The resulting risk maps will complement risk assessments performed with the recently developed Harmonia+ protocol to assess risks posed by emergent species to biodiversity and human, plant, and animal health. The use of open data will ensure that interested stakeholders in Belgium and abroad can make use of the information we generate. The open science ensures everyone is free to adopt and adapt the workflow for different scenarios and regions. The checklist will be used at national level, but will also serve as the Belgian reference for international databases (IUCN - GRIIS, EASIN and impact assessments (IPBES, SEBI. The workflow will be showcased through GEO BON, the Invasivesnet network and the COST Actions Alien Challenge and ParrotNet. The observations and outcomes of risk evaluations will be used to provide science-based support for the implementation of IAS policies at the regional, federal and EU levels. The publication of Belgian data and checklists on IAS is particularly timely in light of the currently ongoing EU IAS Regulation and its implementation in Belgium. By proving that automated workflows can provide

  15. 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...

  16. 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.

  17. Invasive alien plants and water resources in South Africa: current understanding, predictive ability and research challenges

    CSIR Research Space (South Africa)

    Gorgens, AHM

    2004-01-01

    Full Text Available Predictions that invasive alien Plants would use significant amounts of water were a major factor in the establishment of South Africa's Working for Water programme, which aims to protect water resources by clearing these plants. The predictions...

  18. 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...

  19. 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...

  20. 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...

  1. 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 stream_source_info Alien invasive vascular plants in South African natural and semi-natural environments.pdf.txt stream_content_type text/plain stream_size 47 Content-Encoding ISO-8859-1 stream_name Alien invasive vascular plants... in South African natural and semi-natural environments.pdf.txt Content-Type text/plain; charset=ISO-8859-1 ...

  2. 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.

  3. 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.

  4. 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.

  5. 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

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

    African Journals Online (AJOL)

    Kabir Peerbhay

    This paper reviews remote sensing techniques that have been used in ... plant substrates, soil properties, the microclimate, water relations, density and height of vegetation ... the distribution of alien plant invader propagules in support of controlling the spread of alien .... Additionally, a precise weed detection system.

  7. 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 disease

  8. 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.

  9. Temporal introduction patterns of invasive alien plant species to Australia

    Directory of Open Access Journals (Sweden)

    Brad Murray

    2012-05-01

    Full Text Available We examined temporal introduction patterns of 132 invasive alien plant species (IAPS to Australia since European colonisation in 1770. Introductions of IAPS were high during 1810–1820 (10 species, 1840–1880 (51 species, 38 of these between 1840 and 1860 and 1930–1940 (9 species. Conspicuously few introductions occurred during 10-year periods directly preceding each introduction peak. Peaks during early European settlement (1810–1820 and human range expansion across the continent (1840-1860 both coincided with considerable growth in Australia’s human population. We suggest that population growth during these times increased the likelihood of introduced plant species becoming invasive as a result of increased colonization and propagule pressure. Deliberate introductions of IAPS (104 species far outnumbered accidental introductions (28 species and were particularly prominent during early settlement. Cosmopolitan IAPS (25 species and those native solely to South America (53 species, Africa (27 species and Asia (19 species have been introduced deliberately and accidentally to Australia across a broad period of time. A small number of IAPS, native solely to Europe (5 species and North America (2 species, were all introduced to Australia prior to 1880. These contrasting findings for native range suggest some role for habitat matching, with similar environmental conditions in Australia potentially driving the proliferation of IAPS native to southern-hemisphere regions. Shrub, tree and vine species dominated IAPS introduced prior to 1840, with no grasses or forbs introduced during early colonisation. Since 1840, all five growth forms have been introduced deliberately and accidentally in relatively large numbers across a broad period of time. In particular, a large number of grass and forb IAPS were deliberately introduced between 1840 and 1860, most likely a direct result of the introduction of legislation promoting intensive agriculture across

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

    African Journals Online (AJOL)

    Yusuf Adam

    socio-economic impacts such as interrupting the supply of ecosystem goods ... programs of three IAPs in two urban nature reserves within the eThekwini Municipality. ...... do we understand the impacts of alien species on ecosystem services?

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

    African Journals Online (AJOL)

    species and their invasion ecology also differs (Van Wilgen et al., ... as transformed (e.g. cultivated, urban) in the national land cover ... spatial data sets supplied with the vegetation map (Mucina and Rutherford, 2006), and the land types from the database ...... impact of invasive alien plants on ecosystem services in South.

  12. "Freshwater killer whales": beaching behavior of an alien fish to hunt land birds.

    Directory of Open Access Journals (Sweden)

    Julien Cucherousset

    Full Text Available The behavioral strategies developed by predators to capture and kill their prey are fascinating, notably for predators that forage for prey at, or beyond, the boundaries of their ecosystem. We report here the occurrence of a beaching behavior used by an alien and large-bodied freshwater predatory fish (Silurus glanis to capture birds on land (i.e. pigeons, Columbia livia. Among a total of 45 beaching behaviors observed and filmed, 28% were successful in bird capture. Stable isotope analyses (δ(13C and δ(15N of predators and their putative prey revealed a highly variable dietary contribution of land birds among individuals. Since this extreme behavior has not been reported in the native range of the species, our results suggest that some individuals in introduced predator populations may adapt their behavior to forage on novel prey in new environments, leading to behavioral and trophic specialization to actively cross the water-land interface.

  13. Freshwater Killer Whales”: Beaching Behavior of an Alien Fish to Hunt Land Birds

    Science.gov (United States)

    Cucherousset, Julien; Boulêtreau, Stéphanie; Azémar, Frédéric; Compin, Arthur; Guillaume, Mathieu; Santoul, Frédéric

    2012-01-01

    The behavioral strategies developed by predators to capture and kill their prey are fascinating, notably for predators that forage for prey at, or beyond, the boundaries of their ecosystem. We report here the occurrence of a beaching behavior used by an alien and large-bodied freshwater predatory fish (Silurus glanis) to capture birds on land (i.e. pigeons, Columbia livia). Among a total of 45 beaching behaviors observed and filmed, 28% were successful in bird capture. Stable isotope analyses (δ13C and δ15N) of predators and their putative prey revealed a highly variable dietary contribution of land birds among individuals. Since this extreme behavior has not been reported in the native range of the species, our results suggest that some individuals in introduced predator populations may adapt their behavior to forage on novel prey in new environments, leading to behavioral and trophic specialization to actively cross the water-land interface. PMID:23227213

  14. "Freshwater killer whales": beaching behavior of an alien fish to hunt land birds.

    Science.gov (United States)

    Cucherousset, Julien; Boulêtreau, Stéphanie; Azémar, Frédéric; Compin, Arthur; Guillaume, Mathieu; Santoul, Frédéric

    2012-01-01

    The behavioral strategies developed by predators to capture and kill their prey are fascinating, notably for predators that forage for prey at, or beyond, the boundaries of their ecosystem. We report here the occurrence of a beaching behavior used by an alien and large-bodied freshwater predatory fish (Silurus glanis) to capture birds on land (i.e. pigeons, Columbia livia). Among a total of 45 beaching behaviors observed and filmed, 28% were successful in bird capture. Stable isotope analyses (δ(13)C and δ(15)N) of predators and their putative prey revealed a highly variable dietary contribution of land birds among individuals. Since this extreme behavior has not been reported in the native range of the species, our results suggest that some individuals in introduced predator populations may adapt their behavior to forage on novel prey in new environments, leading to behavioral and trophic specialization to actively cross the water-land interface.

  15. 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.

  16. 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.

  17. 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

  18. 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 CO2 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 CO2 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 CO2 enrichment, may further increase the spread of invasive plants in the future. © 2017 John Wiley & Sons Ltd.

  19. Recovery of endemic dragonflies after removal of invasive alien trees.

    Science.gov (United States)

    Samways, Michael J; Sharratt, Norma J

    2010-02-01

    Because dragonflies are very sensitive to alien trees, we assessed their response to large-scale restoration of riparian corridors. We compared three types of disturbance regime--alien invaded, cleared of alien vegetation, and natural vegetation (control)--and recorded data on 22 environmental variables. The most significant variables in determining dragonfly assemblages were percentage of bank cover and tree canopy cover, which indicates the importance of vegetation architecture for these dragonflies. This finding suggests that it is important to restore appropriate marginal vegetation and sunlight conditions. Recovery of dragonfly assemblages after the clearing of alien trees was substantial. Species richness and abundance at restored sites matched those at control sites. Dragonfly assemblage patterns reflected vegetation succession. Thus, initially eurytopic, widespread species were the main beneficiaries of the removal of alien trees, and stenotopic, endemic species appeared after indigenous vegetation recovered over time. Important indicator species were the two national endemics (Allocnemis leucosticta and Pseudagrion furcigerum), which, along with vegetation type, can be used to monitor return of overall integrity of riparian ecology and to make management decisions. Endemic species as a whole responded positively to restoration, which suggests that indigenous vegetation recovery has major benefits for irreplaceable and widespread generalist species.

  20. 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 . (1991) Rapid invasion of Fraxinus ornus L. along the Herault River system in southern France: the importance of seed dispersal by water. Journal of Biogeography, 18, 7–12. Tinley K.L. (1991) Towards harmony with the land: the drainage basin... riparian zones to be more invaded by alien species than other plant communities, and rivers may function as dispersal corridors for the rapid spread of invasive alien plants across landscapes (The´baud & Debussche, 1991; Pyseˇk & Prach, 1994; Planty...

  1. 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

  2. A risk assessment system for alien plant bio-invasion in Xiamen of China

    Institute of Scientific and Technical Information of China (English)

    OU Jian; LU Changyi; DesmondK.O'TOOLE

    2008-01-01

    Bio-invasion has caused serious ecosystem damage and enormous economic losses in China, and it has been the greatest factor to island bio-diversity reduction. Xiamen, as an important seaport with a relatively high conservation value, is particularly vulnerable to bio-invasion for its typical island ecosystem as well as frequent human-made disturbance. As a result of field surveys, literature review, and consultation with experts, a list of 67 alien plants identified as major invaders (12 species) and emerging invaders (55 species) in Xiamen has been compiled. Based on the analysis of the current situation of bio-invasion in Xiamen, a risk assessment system for alien plant invasion has been designed using a ranking system and an analytic hierarchy process. The system consists of 17 secondary indices, grouped into 6 primary indices reflecting the different stages in the bio-invasion process: introduction, establishment, dispersion, current range, infestation, and artificial control. Biogeographical, ecological, and experience-linked aspects of the species as well as artificial disturbance were taken into account in the index selection and criterion development. The system was then validated (and worked well) using fifty well-known alien plant species as candidates. Appropriate recommendations are proposed to help local policy-makers prioritize their decisions on such alien plants.

  3. 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.

  4. 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

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

    Directory of Open Access Journals (Sweden)

    A. ZENETOS

    2012-12-01

    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

  6. 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.

  7. Public attitude in the city of Belgrade towards invasive alien plant species

    Directory of Open Access Journals (Sweden)

    Tomićević Jelena

    2012-01-01

    Full Text Available Biological invasions are seen as a major threat to biodiversity at a global level, while the number of new invasions is increasing at an alarming rate. Raising the awareness of the public, academic world and policy makers about the dangers caused by invasive species, is essential for the creation of the support needed to implement and coordinate the policies necessary to address this problem. The aim of this study is to determine the level of local public awareness of the existence of these plant species, examine the public attitude towards alien invasive plant species and willingness to get involved in the prevention of their spreading. The survey was conducted in four nurseries on the territory of the City of Belgrade and the investigation dealt only with alien invasive woody plant species. Thirty customers were questioned in each of the four nurseries. The results show that local public is uninformed on the issue of invasive plant species. It is necessary to constantly and intensively raise their awareness of this issue, as well as the awareness of harmful consequences that may occur due to the uncontrolled spreading of alien invasive species. This refers not only to the population that visits the nurseries and buys the plants there and to those employed in plant production and selling, but also to the whole local public and decision makers.

  8. Antagonistic interactions between an invasive alien and a native coccinellid species may promote coexistence.

    Science.gov (United States)

    Hentley, William T; Vanbergen, Adam J; Beckerman, Andrew P; Brien, Melanie N; Hails, Rosemary S; Jones, T Hefin; Johnson, Scott N

    2016-07-01

    Despite the capacity of invasive alien species to alter ecosystems, the mechanisms underlying their impact remain only partly understood. Invasive alien predators, for example, can significantly disrupt recipient communities by consuming prey species or acting as an intraguild predator (IGP). Behavioural interactions are key components of interspecific competition between predators, yet these are often overlooked invasion processes. Here, we show how behavioural, non-lethal IGP interactions might facilitate the establishment success of an invading alien species. We experimentally assessed changes in feeding behaviour (prey preference and consumption rate) of native UK coccinellid species (Adalia bipunctata and Coccinella septempunctata), whose populations are, respectively, declining and stable, when exposed to the invasive intraguild predator, Harmonia axyridis. Using a population dynamics model parameterized with these experimental data, we predicted how intraguild predation, accommodating interspecific behavioural interactions, might impact the abundance of the native and invasive alien species over time. When competing for the same aphid resource, the feeding rate of A. bipunctata significantly increased compared to the feeding in isolation, while the feeding rate of H. axyridis significantly decreased. This suggests that despite significant declines in the UK, A. bipunctata is a superior competitor to the intraguild predator H. axyridis. In contrast, the behaviour of non-declining C. septempunctata was unaltered by the presence of H. axyridis. Our experimental data show the differential behavioural plasticity of competing native and invasive alien predators, but do not explain A. bipunctata declines observed in the UK. Using behavioural plasticity as a parameter in a population dynamic model for A. bipunctata and H. axyridis, coexistence is predicted between the native and invasive alien following an initial period of decline in the native species. We

  9. 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...

  10. Clearing of invasive alien plants in South Africa: a preliminary assessment of costs and progress

    CSIR Research Space (South Africa)

    Marais, R

    2004-01-01

    Full Text Available This paper provides estimates of the costs of clearing important species of invasive alien plants, as well as of progress made with clearing, based on data from a recently developed GIS-based project information system. Before the deployment...

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

    NARCIS (Netherlands)

    Vane, Maurice; Runhaar, Hens A. C.

    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

  12. Evolution of fire and invasive alien plant management practices in fynbos

    CSIR Research Space (South Africa)

    Van Wilgen, BW

    2009-09-01

    Full Text Available The history and development of fire and invasive alien plant management policies in fynbos during the 20th century are reviewed. Fire was initially condemned outright as a destructive force, but as its vital role became better understood, management...

  13. 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…

  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, import

  15. 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...

  16. 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...

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

    African Journals Online (AJOL)

    1989-04-18

    Apr 18, 1989 ... Effects of alien woody plant invasion on the birds of Mountain Fynbos in the Cape of Good ..... and Cape white-eye (Zosterops pal/idus) which are associated with the ... plot (Table 3) where Cape sugarbirds, sun birds and red-.

  19. Experimental study to control the upstream migration of invasive alien fish species by submerged weir

    Science.gov (United States)

    Sakuma, Masami; Kunimatsu, Fumihiro; Tsuchiya, Taku; Kawamura, Makiko; Fujita, Hiroshi

    Largemouth bass and Bluegill, major invasive alien fish species in Japan, have been extending their habitat ranges over not only Lake Biwa and the lagoons but also surrounding waters connected to them through small rivers and canals. Their increasing number is bringing about the reduction in the number of native fish species. To prevent the spread of these alien species through small rivers and canals during breeding season of the native fish (crucian carp), this study experimentally examined the effect of a submerged weir on controlling upstream migration of the alien species and the native fish. As a result of the experiment, the ratio of the alien species migrating upstream decreased as the weir height rose, whereas the ratio did not show the same trend in the case of the native fish. The ratio of the alien species also decreased as the overflow velocity over the weir rose. On the other hand, the ratio of the native fish increased as the overflow velocity rose up to 1.0m/s and decreased thereafter. These results suggest that the submerged weir may control upstream migration of the alien species to surrounding waters through small rivers and canals without interfering with the reproductive migration of the native fish.

  20. 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)

  1. Ornamental Plants as Invasive Aliens: Problems and Solutions in Kruger National Park, South Africa

    Science.gov (United States)

    Foxcroft, Llewellyn C.; Richardson, David M.; Wilson, John R. U.

    2008-01-01

    The most widespread invasive alien plant species in South Africa’s Kruger National Park (KNP) were either introduced unintentionally along rivers and roads, or intentionally for use as ornamentals. We examine the spatial distribution of ornamental alien plants in KNP, look at the link between human population size, history, and species richness, and show how the distribution of particular species reflects the likely history of ornamental plantings. Results are used to assess whether past management actions have been appropriately directed. Two hundred and fifty-eight alien species have been recorded in the 36 tourist camps and staff villages. The number of staff housed in villages explains much of the diversity of cultivated alien plant species. Older camps also tend to have more ornamental alien plant species. However, the lack of a strong link between camp age and number of cultivated species suggests that ornamental plants have been widely spread around the KNP by humans. We also show that increased camp activity (either size or age) has led to more ornamental species, while, with the notable exception of Skukuza, camp activity has had a much smaller effect on the number of noncultivated species. Noncultivated species tend to be naturally dispersed, as opposed to directly spread by humans between camps. Past management prioritized certain species on the basis of their potential to invade KNP and on the prevailing national legislation. These species were removed manually and follow-up control was carried out. Once the priority species were deemed to be under control, less invasive species were targeted. All alien species were removed from vacated houses, regardless of the potential invasiveness of the species.

  2. Global threats from invasive alien species in the twenty-first century and national response capacities

    Science.gov (United States)

    Early, Regan; Bradley, Bethany A.; Dukes, Jeffrey S.; Lawler, Joshua J.; Olden, Julian D.; Blumenthal, Dana M.; Gonzalez, Patrick; Grosholz, Edwin D.; Ibañez, Ines; Miller, Luke P.; Sorte, Cascade J. B.; Tatem, Andrew J.

    2016-01-01

    Invasive alien species (IAS) threaten human livelihoods and biodiversity globally. Increasing globalization facilitates IAS arrival, and environmental changes, including climate change, facilitate IAS establishment. Here we provide the first global, spatial analysis of the terrestrial threat from IAS in light of twenty-first century globalization and environmental change, and evaluate national capacities to prevent and manage species invasions. We find that one-sixth of the global land surface is highly vulnerable to invasion, including substantial areas in developing economies and biodiversity hotspots. The dominant invasion vectors differ between high-income countries (imports, particularly of plants and pets) and low-income countries (air travel). Uniting data on the causes of introduction and establishment can improve early-warning and eradication schemes. Most countries have limited capacity to act against invasions. In particular, we reveal a clear need for proactive invasion strategies in areas with high poverty levels, high biodiversity and low historical levels of invasion. PMID:27549569

  3. Global threats from invasive alien species in the twenty-first century and national response capacities.

    Science.gov (United States)

    Early, Regan; Bradley, Bethany A; Dukes, Jeffrey S; Lawler, Joshua J; Olden, Julian D; Blumenthal, Dana M; Gonzalez, Patrick; Grosholz, Edwin D; Ibañez, Ines; Miller, Luke P; Sorte, Cascade J B; Tatem, Andrew J

    2016-08-23

    Invasive alien species (IAS) threaten human livelihoods and biodiversity globally. Increasing globalization facilitates IAS arrival, and environmental changes, including climate change, facilitate IAS establishment. Here we provide the first global, spatial analysis of the terrestrial threat from IAS in light of twenty-first century globalization and environmental change, and evaluate national capacities to prevent and manage species invasions. We find that one-sixth of the global land surface is highly vulnerable to invasion, including substantial areas in developing economies and biodiversity hotspots. The dominant invasion vectors differ between high-income countries (imports, particularly of plants and pets) and low-income countries (air travel). Uniting data on the causes of introduction and establishment can improve early-warning and eradication schemes. Most countries have limited capacity to act against invasions. In particular, we reveal a clear need for proactive invasion strategies in areas with high poverty levels, high biodiversity and low historical levels of invasion.

  4. Research Progress on Invasion Mechanism of Alien Invasive Species%外来物种入侵机制的研究进展

    Institute of Scientific and Technical Information of China (English)

    张巧; 郝建锋

    2011-01-01

    To make foundation for further study of alien plant invasion and fundamentally control alien plant invasion, in this paper the invasion status of alien plants in China was generalized, the process and mechanisms of biological invasion were analyzed and prevention and control measures were proposed which is of great significance to prevention of malignant alien invasive species invasion.%为了从根本上有效控制外来植物的入侵,为外来植物入侵的深入研究提供参考,综述了我国外来物种入侵现状,分析外来物种入侵过程及入侵机制,提出对入侵物种的预防和控制措施,对于防治恶性外来入侵物种有重要意义.

  5. 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...

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

    CSIR Research Space (South Africa)

    Richardson, DM

    2007-01-01

    Full Text Available conifers has a much shorter history in South America, and invasions are a recent phenomenon. A workshop was convened in Argentina in May 2007 to discuss the rapid emergence of problems with invasive conifers in South America. Workshop delegates agreed that...

  7. Invasive alien organisms in South West Africa/Namibia

    CSIR Research Space (South Africa)

    Brown, CJ

    1985-01-01

    Full Text Available to place. The areas most prone to invasion are the river washes, particularly those rising on or running through farmlands. Seed dispersal in these areas is mainly waterborne. Other invasion-prone ecosystems are those associated with perennial river systems...

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

    Science.gov (United States)

    Lucy, Frances E; 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. Status, Impact and Management of Invasive Alien Species in Tanzania

    African Journals Online (AJOL)

    They contribute to economic hardship and social instability, placing ... of plants and animal species that are regarded as important sources of livelihoods. ... long term strategies to address the issue of invasive species in many institutions.

  10. 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.

  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. 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

  14. Checklist of invasive alien species in CSIR-NBRI Botanic Garden, Lucknow, India

    Directory of Open Access Journals (Sweden)

    Shilpi Singh

    2015-08-01

    Full Text Available The invasive alien species of CSIR-NBRI Botanic Garden are enumerated and their impact on the surrounding ecosystem are discussed. This study deals with the information on habit, nativity and family of plant species occurring in the area of study. A total of 103 invasive alien species under 86 genera and 36 families were recorded. Among these, the eudicotyledons represent 85 species, 69 genera and 32 families; monocotyledons represent 18 species, 17 genera and 4 families. In terms of nativity, species from Tropical America are the most dominant group with 34 species. In addition, based on life forms, herbs are dominant (88 species, followed by shrubs (8 species, climbers (4 species and trees (3 species.

  15. Insect Eradication and Containment of Invasive Alien Species

    Science.gov (United States)

    Insect eradication programs are nearly always targeted at recently arrived invasive species with significant pest potential. They attempt to contain a pest to a defined area and then completely eliminate the pest from that area. From a Federal regulatory standpoint, eradication programs are undert...

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

    OpenAIRE

    Sandro Bertolino; Piero Genovesi

    2005-01-01

    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...

  17. [Fast catalogue of alien invasive weeds by Vis/NIR spectroscopy].

    Science.gov (United States)

    Yu, Jia-Jia; Zou, Wei; He, Yong; Xu, Zheng-Hao

    2009-11-01

    The feasibility of visible and short-wave near-infrared spectroscopy (VIS/WNIR) techniques as means for the nondestructive and fast detection of alien invasive weeds was evaluated. Selected sensitive bands were found validated. In the present study, 3 kinds of alien invasive weeds, Veronica persica, Veronica polita, and Veronica arvensis Linn, and one kind of local weed, Lamiaceae amplexicaule Linn, were employed. The results showed that visible and NIR (Vis/NIR) technology could be introduced in classification of the alien invasive weeds or local weed with the similar outline. Thirty x 4 weeds samples were randomly selected for the calibration set, while the remaining 20 x 4 samples for the prediction set. Smoothing methods of moving average and standard normal variate (SNV) were used to pretreat spectra data. Based on principal components analysis, soft independent models of class analogy (SIMCA) were applied to make the model. Four frontal principal components of each catalogues were applied as the input of SIMCA, and with a significance level of 0.05, recognition ratio of 78.75% was obtained. The average prediction result is 90% except for Veronica polita. According to the modeling power of each spectra data in SIMCA, some possible sensitive bands, 496-521, 589-626 and 789-926 nm, were founded. By using these possible sensitive bands as the inputs of least squares support vector machine (LS-SVM), and setting the result of LS-SVM as the object function value of genetic algorithm (GA), mutational rate, crossover rate and population size were set up as 0.9, 0.5 and 50 respectively. Finally recognition ratio of 95.63% was obtained. The prediction results of 95.63% indicated that the selected wavelengths reflected the main characteristics of the four weeds, which proposed a new way to accelerate the research on cataloguing alien invasive weeds.

  18. 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.

  19. The quest gone astray: tracing horror in alien invasion television series of the new millenium

    OpenAIRE

    Ay, Tuba

    2008-01-01

    91 pages The starting years of the new millennium, explicitly the year 2005, witnessed an attempt to bring the science fiction genre to the mainstream like the attempt in the 1950s, however, this time not through the medium of film but through television. Conversely, the outcome is not the same for the television series that have alien invasion narratives, if compared to the B-movies of the 1950s that had similar narratives. Mostly concentrated upon the texts of the series Invasion and Thr...

  20. 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.

  1. New alien barnacles in the Azores and some remarks on the invasive potential of Balanidae

    Science.gov (United States)

    Torres, Paulo; Costa, Ana Cristina; Dionísio, Maria Ana

    2012-12-01

    Global homogenization of biota is underway through worldwide introduction and establishment of non-indigenous (exotic) species. Organisms fouling ship hulls are continually in transit and can affect communities through biodiversity loss and serious damage to economy and public health. In the Azores, for the first time, underwater alien species prospection was conducted in marinas and recreational harbours, at São Miguel Island. Populations of three locally previously unknown barnacle species were found: Amphibalanus amphitrite, Amphibalanus eburneus and Perforatus perforatus. These species account for the more than 50% of alien barnacles worldwide that belong to Balanidae family. Hence, some considerations about morphology and life cycle of this family are advanced, discussed and related to their invasive potential.

  2. 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 Many invasive alien plant species in South Africa are already well-established and cause substantial damage, while scores of others are at the early stages of invasion (only recently introduced and/or entering a phase of rapid population growth...

  3. 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

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

    Directory of Open Access Journals (Sweden)

    Llewellyn C. Foxcroft

    2009-01-01

    Full Text Available The Kruger National Park (KNP has developed and refined a system of management called ‘strategic adaptive management’ (SAM, which rests on the concept of ‘threshold of potential concern’ (TPC. TPCs represent end-points in a continuum of change. When thresholds are reached – at which point concerns of negative impacts on biodiversity are raised – management options are explicitly considered and implemented. This paper describes the TPCs developed for monitoring and managing invasive alien species (IAS. More importantly, however, it describes the conceptual understanding, principles and hypotheses adopted as the foundations for setting these TPCs. In accordance with adaptive management practices, the TPCs will be revised as the ecological and conceptual understanding of invasions grows and information is gained through research in the KNP and elsewhere.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.

  5. Release from belowground enemies and shifts in root traits as interrelated drivers of alien plant invasion success: a hypothesis.

    Science.gov (United States)

    Dawson, Wayne

    2015-10-01

    Our understanding of the interrelated mechanisms driving plant invasions, such as the interplay between enemy release and resource-acquisition traits, is biased by an aboveground perspective. To address this bias, I hypothesize that plant release from belowground enemies (especially fungal pathogens) will give invasive plant species a fitness advantage in the alien range, via shifts in root traits (e.g., increased specific root length and branching intensity) that increase resource uptake and competitive ability compared to native species in the alien range, and compared to plants of the invader in its native range. Such root-trait changes could be ecological or evolutionary in nature. I explain how shifts in root traits could occur as a consequence of enemy release and contribute to invasion success of alien plants, and how they could be interrelated with other potential belowground drivers of invasion success (allelopathy, mutualist enhancement). Finally, I outline the approaches that could be taken to test whether belowground enemy release results in increased competitive ability and nutrient uptake by invasive alien plants, via changes in root traits in the alien range.

  6. 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.

  7. Invasive alien woody plants of the southern and southwestern Cape region, South Africa

    Directory of Open Access Journals (Sweden)

    L. Henderson

    1998-12-01

    Full Text Available The frequency and abundance of invasive alien plants were recorded along roadsides and at watercourse crossings in 82.9% (145/175 of the quarter degree squares in the study area (3I-35°S, 17-25°E and covering ± 90 000 km:. The sur­vey yielded 102 species of which the most prominent (in order of prominence in roadside and veld (natural and modified habitats were: Acacia cyclops, A. saligna and A. mearnsii The most prominent species (in order of prominence in stream- bank habitats were: A. mearnsii, A. saligna and Populus x canescens.

  8. Climatic niche divergence and habitat suitability of eight alien invasive weeds in China under climate change.

    Science.gov (United States)

    Wan, Ji-Zhong; Wang, Chun-Jing; Tan, Jing-Fang; Yu, Fei-Hai

    2017-03-01

    Testing climatic niche divergence and modeling habitat suitability under conditions of climate change are important for developing strategies to limit the introduction and expansion of alien invasive weeds (AIWs) and providing important ecological and evolutionary insights. We assessed climatic niches in both native and invasive ranges as well as habitat suitability under climate change for eight representative Chinese AIWs from the American continent. We used climatic variables associated with occurrence records and developed ecological niche models with Maxent. Interestingly, the climatic niches of all eight AIWs diverged significantly between the native and invasive ranges (the American continent and China). Furthermore, the AIWs showed larger climatic niche breadths in the invasive ranges than in the native ranges. Our results suggest that climatic niche shifts between native and invasive ranges occurred. Thus, the occurrence records of both native and invasive regions must be considered when modeling and predicting the spatial distributions of AIWs under current and future climate scenarios. Owing to high habitat suitability, AIWs were more likely to expand into regions of low latitude, and future climate change was predicted to result in a shift in the AIWs in Qinghai and Tibet (regions of higher altitude) as well as Heilongjiang, Jilin, Liaoning, Inner Mongolia, and Gansu (regions of higher latitude). Our results suggest that we need measures to prevent and control AIW expansion at the country-wide level.

  9. Species pools, community completeness and invasion: disentangling diversity effects on the establishment of native and alien species.

    Science.gov (United States)

    Bennett, Jonathan A; Riibak, Kersti; Kook, Ene; Reier, Ülle; Tamme, Riin; Guillermo Bueno, C; Pärtel, Meelis

    2016-12-01

    Invasion should decline with species richness, yet the relationship is inconsistent. Species richness, however, is a product of species pool size and biotic filtering. Invasion may increase with richness if large species pools represent weaker environmental filters. Measuring species pool size and the proportion realised locally (completeness) may clarify diversity-invasion relationships by separating environmental and biotic effects, especially if species' life-history stage and origin are accounted for. To test these relationships, we added seeds and transplants of 15 native and alien species into 29 grasslands. Species pool size and completeness explained more variation in invasion than richness alone. Although results varied between native and alien species, seed establishment and biotic resistance to transplants increased with species pool size, whereas transplant growth and biotic resistance to seeds increased with completeness. Consequently, species pools and completeness represent multiple independent processes affecting invasion; accounting for these processes improves our understanding of invasion.

  10. 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

  11. 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.

  12. Climate change vulnerability of native and alien freshwater fishes of California: a systematic assessment approach

    National Research Council Canada - National Science Library

    Moyle, Peter B; Kiernan, Joseph D; Crain, Patrick K; Quiñones, Rebecca M

    2013-01-01

    ... vulnerability to climate change of freshwater fishes in California, USA. The method uses expert knowledge, supported by literature reviews of status and biology of the fishes, to score ten metrics for both (1...

  13. 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.

  14. 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 conflicting fire management requirements for plantation safety against fynbos conservation; (2) the continual invasion of fynbos by fire-propagated alien pines sourced from plantations; (3) inadequate resources to redress the ‘invasion debt’ caused...

  15. 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.

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

    Science.gov (United States)

    Emer, Carine; Vaughan, Ian P.; Hiscock, Simon; Memmott, Jane

    2015-01-01

    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. PMID:26633170

  17. Preference and Prey Switching in a Generalist Predator Attacking Local and Invasive Alien Pests

    Science.gov (United States)

    Jaworski, Coline C.; Bompard, Anaïs; Genies, Laure; Amiens-Desneux, Edwige; Desneux, Nicolas

    2013-01-01

    Invasive pest species may strongly affect biotic interactions in agro-ecosystems. The ability of generalist predators to prey on new invasive pests may result in drastic changes in the population dynamics of local pest species owing to predator-mediated indirect interactions among prey. On a short time scale, the nature and strength of such indirect interactions depend largely on preferences between prey and on predator behavior patterns. Under laboratory conditions we evaluated the prey preference of the generalist predator Macrolophus pygmaeus Rambur (Heteroptera: Miridae) when it encounters simultaneously the local tomato pest Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) and the invasive alien pest Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). We tested various ratios of local vs. alien prey numbers, measuring switching by the predator from one prey to the other, and assessing what conditions (e.g. prey species abundance and prey development stage) may favor such prey switching. The total predation activity of M. pygmaeus was affected by the presence of T. absoluta in the prey complex with an opposite effect when comparing adult and juvenile predators. The predator showed similar preference toward T. absoluta eggs and B. tabaci nymphs, but T. absoluta larvae were clearly less attacked. However, prey preference strongly depended on prey relative abundance with a disproportionately high predation on the most abundant prey and disproportionately low predation on the rarest prey. Together with the findings of a recent companion study (Bompard et al. 2013, Population Ecology), the insight obtained on M. pygmaeus prey switching may be useful for Integrated Pest Management in tomato crops, notably for optimal simultaneous management of B. tabaci and T. absoluta, which very frequently co-occur on tomato. PMID:24312646

  18. PHYTOSOCIOLOGY OF INVASIVE ALIEN THEROPHYTIC FLORA OF PEDDAGATTU, THE PROPOSED SITE FOR URANIUM MINING IN NALGONDA DISTRICT, TELANGANA, INDIA

    Directory of Open Access Journals (Sweden)

    A. BALEESHWAR REDDY1*, V. HANUMANTHA RAO AND V. VASUDEVA RAO2

    2014-10-01

    The present investigation reflects the findings of invasive alien species and phytosociological attributes at Peddagattu (Lambapur, Nalgonda district, Telangana, India. Phytosociology studies on Invasive alien species were collected during 2010-2012. Of 30 species of taxa are belonging to 29 genera and 17 families. Compositae is the most dominant family representing   with 6 species (20% followed by Malvaceae 4 species (13%, Solanaceae 3 species (10%, Amaranthaceae  and Leguminaceae with 2 species (7% each. About 60% of these alien species were introduced from Tropical America followed by Tropical Africa (13%, and Trop. C. America (7%. Among the species, Tridax procumbens shows the highest IVI value (12.94 and followed by Cleome viscose (7.12, Waltheria indica (6.13 and Parthenium hysterophorus (5.57 and Typha angustata (5.22.

  19. 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

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

    NARCIS (Netherlands)

    Trouwborst, Arie

    2015-01-01

    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 Habitat

  1. 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 classification of invasive alien plant species in South Africa: towards prioritizing 629 species and areas for management action. South African Journal of Science 100, 630 53?64. 631 Olckers, T., 2011. Biological control of Solanum mauritianum Scop...

  2. 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...

  3. A biome-scale assessment of the impact of invasive alien plants on ecosystem services in South Africa.

    Science.gov (United States)

    van Wilgen, B W; Reyers, B; Le Maitre, D C; Richardson, D M; Schonegevel, L

    2008-12-01

    This paper reports an assessment of the current and potential impacts of invasive alien plants on selected ecosystem services in South Africa. We used data on the current and potential future distribution of 56 invasive alien plant species to estimate their impact on four services (surface water runoff, groundwater recharge, livestock production and biodiversity) in five terrestrial biomes. The estimated reductions in surface water runoff as a result of current invasions were >3000 million m(3) (about 7% of the national total), most of which is from the fynbos (shrubland) and grassland biomes; the potential reductions would be more than eight times greater if invasive alien plants were to occupy the full extent of their potential range. Impacts on groundwater recharge would be less severe, potentially amounting to approximately 1.5% of the estimated maximum reductions in surface water runoff. Reductions in grazing capacity as a result of current levels of invasion amounted to just over 1% of the potential number of livestock that could be supported. However, future impacts could increase to 71%. A 'biodiversity intactness index' (the remaining proportion of pre-modern populations) ranged from 89% to 71% for the five biomes. With the exception of the fynbos biome, current invasions have almost no impact on biodiversity intactness. Under future levels of invasion, however, these intactness values decrease to around 30% for the savanna, fynbos and grassland biomes, but to even lower values (13% and 4%) for the two karoo biomes. Thus, while the current impacts of invasive alien plants are relatively low (with the exception of those on surface water runoff), the future impacts could be very high. While the errors in these estimates are likely to be substantial, the predicted impacts are sufficiently large to suggest that there is serious cause for concern.

  4. Exotic and invasive terrestrial and freshwater animal species in the Dutch Caribbean

    NARCIS (Netherlands)

    Buurt, van G.; Debrot, A.O.

    2011-01-01

    An overview of 72 invasive animals of the terrestrial and freshwater environments of the Dutch Caribbean, eleven of which are no longer present. All invasive animals that are principally agricultural pests and or animal and plant diseases (46 species) are excluded as these are discussed separately

  5. Exotic and invasive terrestrial and freshwater animal species in the Dutch Caribbean

    NARCIS (Netherlands)

    Buurt, van G.; Debrot, A.O.

    2011-01-01

    An overview of 72 invasive animals of the terrestrial and freshwater environments of the Dutch Caribbean, eleven of which are no longer present. All invasive animals that are principally agricultural pests and or animal and plant diseases (46 species) are excluded as these are discussed separately e

  6. 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.

  7. Ecdysteroids in the larvae of Opogona sacchari (Bojer), a invasive alien pest

    Institute of Scientific and Technical Information of China (English)

    WANG FangHai; ZHANG GuRen; WEN RuiZhen; HE GuoFeng

    2007-01-01

    In order to understand the composition and quantitative variation of ecdysteriods in the larvae of Opogona sacchari (Bojer), a invasive alien pest, we analyzed the larval ecdysteroid composition and titers in this pest. The main component of ecdysteriods in the larvae of O. Sacchari is 20-hydroxyecdysone, and also there is a little 26-hydroxyecdysone. The titer of ecdysteriods in the larvae from the 1st instar to the 7th instar was gotten higher gradually compared on ng ecdysteroid/larva, but no regularity could be found about the titer if compared on ng ecdysteroid/g avoirdupois. There was only one peak of ecdysteroids (0.5475 ng/larva) showed at day 2 during the developmental time of the 6th instar larvae. However, there were two peaks appearing during the developmental time of the 7th instar larvae , one peak (0.29415 ng/larva) at day 3, another (0.214 ng/larva) at day 5.

  8. 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

  9. 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

  10. Analyzing the Social Factors That Influence Willingness to Pay for Invasive Alien Species Management Under Two Different Strategies: Eradication and Prevention

    Science.gov (United States)

    García-Llorente, Marina; Martín-López, Berta; Nunes, Paulo A. L. D.; González, José A.; Alcorlo, Paloma; Montes, Carlos

    2011-09-01

    Biological invasions occur worldwide, and have been the object of ecological and socio-economic research for decades. However, the manner in which different stakeholder groups identify the problems associated with invasive species and confront invasive species management under different policies remains poorly understood. In this study, we conducted an econometric analysis of the social factors influencing willingness to pay for invasive alien species management under two different regimes: eradication and prevention in the Doñana Natural Protected Area (SW Spain). Controlling for the participation of local residents, tourists and conservationists, email and face-to-face questionnaires were conducted. Results indicated that respondents were more willing to pay for eradication than prevention; and public support for invasive alien species management was influenced by an individual's knowledge and perception of invasive alien species, active interest in nature, and socio-demographic attributes. We concluded that invasive alien species management research should confront the challenges to engage stakeholders and accept any tradeoffs necessary to modify different conservation policies to ensure effective management is implemented. Finally, our willingness to pay estimates suggest the Department of Environment of Andalusian Government has suitable social support to meet the budgetary expenditures required for invasive alien species plans and adequate resources to justify an increase in the invasive alien species management budget.

  11. 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.

  12. 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.

  13. Evaluating invasion risk for freshwater fishes in South Africa

    Directory of Open Access Journals (Sweden)

    Sean M. Marr

    2017-03-01

    Full Text Available Background: South Africa, as a signatory of the Convention on Biological Diversity, has an obligation to identify, prioritise and manage invasive species and their introduction pathways. However, this requires knowledge of the introduction pathways, factors influencing establishment success, invasive potential, current distributions and ecological impacts. Objectives: To evaluate the Fish Invasiveness Screening Kit (FISK to predict the invasion risk posed by fish species proposed for introduction into South Africa. Method: FISK assessments were compiled for species whose invasion status in South Africa was known. A Receiver operating characteristic (ROC analysis was conducted to calibrate the FISK for South Africa. The calibrated FISK was used to evaluate the risk that three species recently proposed for importation for aquaculture could become invasive in South Africa. Results: A FISK score of 14 was identified as the threshold to delineate between species that could become invasive in South Africa and those that are unlikely to become invasive. Of the three species evaluated, Silurus glanis had a high risk of becoming invasive in South Africa, Lates calcarifer was likely to be invasive and Oncorhynchus tshawytscha was unlikely to be invasive in South Africa. Conclusion: FISK was demonstrated to be a useful risk assessment tool to evaluate the invasion risk posed by species proposed for use in aquaculture. For the large number of fish imported for the pet trade, a rapid screening assessment to flag potentially high risk species was recommended prior to a full FISK assessment for flagged species.

  14. APPROACHES ON THE INVASIVE ALIEN TAXA IN ROMANIA - AMBROSIA ARTEMISIIFOLIA (RAGWEED I

    Directory of Open Access Journals (Sweden)

    Nicoleta IANOVICI

    2009-01-01

    Full Text Available The aim of the present contribution was to determine the situation of Ambrosia artemisiifolia in Romania. A. artemisiifolia has a pronounced invasive character and is anemophilous, contrary to most Asteraceae. This paper is a brief summary about the researches on the alien plant Ambrosia artemisiifolia in Romania. At present, this alien plant is in the process of acclimatization and naturalization in our country. Till now it has indicated from all Romanian provinces, the spread of this taxon through our country is still incomplete known, at about a century since its first identification at Orşova. Nowadays the agricultural areas are greatly infested in Romania. However, the infestations on waste land or roadsides are rarely controlled. The annual pollen counts show an increasing tendency, indicating an increased local population. Ambrosia artemisiifolia has been studied by a high number of romanian scientists and many articles have been written on the topic. For the study of the spreading of the Ambrosia artemisiifolia L. species in the Western field of the country it was established as a study perimeter an areal which situates between the adminitrative limits of Timiş county. In 2008 the presence of the species was noticed in 49 locations. In 2009 - 2011, the observations continued and it was observed the emergence of the species in 28 new locations, also the expansion and amplification in the pryor locations. In the years 2010-2011 have been made many observations in other 33 counties and Bucureşti. The determinations were made in the months of June-September. In this work were listed a number of sites across Romania, where A. artemisiifolia vegetate. Currently the biggest problem is in the lowland and hill area of macro-regions 1, 3 and 4 where the species A. artemisiifolia is found in the extensive and diverse ecosystems. The paper presents personal observations on some morphological features, anatomical and ecological aspects.

  15. 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.

  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. Phenotypic plasticity and differentiation in an invasive freshwater microalga

    NARCIS (Netherlands)

    Sassenhagen, Ingrid; Wilken, Susanne; Godhe, Anna; Rengefors, Karin

    Recent studies show that both marine and limnic microalgal species often consist of several genetically distinct populations. This is also valid for the nuisance freshwater algae Gonyostomum semen, which originates from acidic, brown water swamp lakes, but can nowadays also be found in clearer lakes

  18. Vectors of invasions in freshwater invertebrates and fishes

    Science.gov (United States)

    Fuller, Pam L.; Canning-Clode, João

    2015-01-01

    Without human assistance, the terrestrial environment and oceans represent barriers to the dispersal of freshwater aquatic organisms. The ability to overcome such barriers depends on the existence of anthropogenic vectors that can transport live organisms to new areas, and the species’ biology to survive the transportation and transplantation into the new environment (Johnson et al., 2006).

  19. 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

  20. 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

  1. 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

  2. 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 invasion of

  3. Recurrent camouflaged invasions and dispersal of an Asian freshwater gastropod in tropical Africa

    OpenAIRE

    Van Bocxlaer, Bert; Clewing, Catharina; Mongindo Etimosundja, Jean-Papy; Kankonda, Alidor; Wembo Ndeo, Oscar; Albrecht, Christian

    2015-01-01

    Background Non-indigenous taxa currently represent a large fraction of the species and biomass of freshwater ecosystems. The accumulation of invasive taxa in combination with other stressors in these ecosystems may alter the habitats to which native taxa are adapted, which could elicit evolutionary changes in native populations and their ecological interactions. Assessing ecological and evolutionary consequences of invasions simultaneously may therefore be the most effective approach to study...

  4. Ecdysteroids in the adults and eggs of Opogona sacchari (Bojer), an invasive alien pest

    Institute of Scientific and Technical Information of China (English)

    WANG FangHai; ZHANG GuRen; WEN RuiZhen; HE GuoFeng

    2008-01-01

    In order to understand the composition and quantitative variation of ecdysteriods in the adults and eggs of Opogona sacchari (Bojer), an invasive alien pest, we analyzed the ecdysteroid composition and titers in the adult and egg of this pest. On day 4 after eclosion, the titer of ecdysteriods in the male adult was 0.080 ng/sdult, much lower than 5.978 ng/adult in the female adult. During the development of ovaries, the titer of ecdysteriods was low on the first two days, and high in the late period, with the peak (10.48 ng/ovary) appearing on day 3. During the development of eggs, the titer of ecdysteriods was about 0.010 ng/egg from day I to day 3, and then decreased to 0.006 ng/egg on day 4. In both adults and eggs, three main components of ecdysteriods were found by identification of HPLC/RIA. They were 20-hydroxyecdysone, 26-hydroxyecdysone, and an unidentified component.

  5. Ecdysteroids in the adults and eggs of Opogona sacchari (Bojer),an invasive alien pest

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to understand the composition and quantitative variation of ecdysteriods in the adults and eggs of Opogona sacchari (Bojer), an invasive alien pest, we analyzed the ecdysteroid composition and titers in the adult and egg of this pest. On day 4 after eclosion, the titer of ecdysteriods in the male adult was 0.080 ng/adult, much lower than 5.978 ng/adult in the female adult. During the development of ovaries, the titer of ecdysteriods was low on the first two days, and high in the late period, with the peak (10.48 ng/ovary) appearing on day 3. During the development of eggs, the titer of ecdysteriods was about 0.010 ng/egg from day 1 to day 3, and then decreased to 0.006 ng/egg on day 4. In both adults and eggs, three main components of ecdysteriods were found by identification of HPLC/RIA. They were 20-hydroxyecdysone, 26-hydroxyecdysone, and an unidentified component.

  6. 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.

  7. Ecdysteroids in the pupae of Opogona sacchari (Bojer), a new invasive alien pest

    Institute of Scientific and Technical Information of China (English)

    WANG Fanghai; ZHANG Guren; WEN Ruizhen; HE Guofeng

    2006-01-01

    In order to understand the composition and quantitative variation of ecdysteriods in the pupae of Opogona sacchari (Bojer), a new invasive alien pest, we analyzed the pupal ecdysteroid composition and titers in this pest. The main component of ecdysteriods in the pupae of O. sacchari is 20-hydroxyecdysone. The titre of ecdysteriods in both male pupae and female pupae get higher gradually, and then decreased slowly after reaching a peak (80 ng/pupa). The titre of ecdysteriods was about 30 ng/pupa in the later stage of pupae. The peak of male pupae appeared on the third day, but the peak of female pupae lasted from the second day to the fourth day during pupal developments. The ecdysteroid content was higher in female pupae than in male pupae during specific pupal time (the 1st, 2nd, 4th, 5th, 6th day). We also found that the titre of ecdysteroids in posterior part of pupae was higher than in anterior part of pupae obviously.

  8. The large-scale removal of mammalian invasive alien species in Northern Europe.

    Science.gov (United States)

    Robertson, Peter A; Adriaens, Tim; Lambin, Xavier; Mill, Aileen; Roy, Sugoto; Shuttleworth, Craig M; Sutton-Croft, Mike

    2017-02-01

    Numerous examples exist of successful mammalian invasive alien species (IAS) eradications from small islands (<10 km(2) ), but few from more extensive areas. We review 15 large-scale removals (mean area 2627 km(2) ) from Northern Europe since 1900, including edible dormouse, muskrat, coypu, Himalayan porcupine, Pallas' and grey squirrels and American mink, each primarily based on daily checking of static traps. Objectives included true eradication or complete removal to a buffer zone, as distinct from other programmes that involved local control to limit damage or spread. Twelve eradication/removal programmes (80%) were successful. Cost increased with and was best predicted by area, while the cost per unit area decreased; the number of individual animals removed did not add significantly to the model. Doubling the area controlled reduced cost per unit area by 10%, but there was no evidence that cost effectiveness had increased through time. Compared with small islands, larger-scale programmes followed similar patterns of effort in relation to area. However, they brought challenges when defining boundaries and consequent uncertainties around costs, the definition of their objectives, confirmation of success and different considerations for managing recolonisation. Novel technologies or increased use of volunteers may reduce costs. Rapid response to new incursions is recommended as best practice rather than large-scale control to reduce the environmental, financial and welfare costs. © 2016 Crown copyright. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

  9. Potential Distribution of Alien Invasive Species and Risk Assessment: a Case Study of Erwinia amylovora in China

    Institute of Scientific and Technical Information of China (English)

    CHEN Chen; CHEN Juan; HU Bai-shi; JIANG Ying-hua; LIU Feng-quan

    2007-01-01

    Alien invasive species represent a severe risk to biodiversity and economy, as in the case of fire blight (Erwinia amylovora), a bacterial disease that originated in North America, which may be released into new locations by means of fruit trade. On the basis of the knowledge of Erwinia amylovora's biophysical characteristics and environmental data, the geographic information system (GIS) has been applied to determine areas where Erwinia amylovora can potentially invade China. Temperature and precipitation, during the blossoming period, are considered to be two critical factors affecting the Erwinia amylovora's suitable climatic zones. This spatial modeling approach was validated from a case study in Europe, where the occurrence of Erwinia amylovora has been proven. The model prediction agreed with the occurrence of the bacteria recorded in Europe, and the same procedure has been applied to produce a potential establishment area in China's two preferential apple cultivation regions, Bohai Bay region and Huangtu Altiplano region. It has been found that areas belonging to the high-risk category are more or less the main apple producing areas, accounting for their great economic importance in China. This methodology provides an initial baseline for assessment, prevention, and management of alien species that may become invasive under certain environmental conditions. In addition, this modeling approach provides a tool for policy makers to use, in making decisions on management practices where alien species are involved.

  10. Multiple invasions into freshwater by pufferfishes (teleostei: tetraodontidae: a mitogenomic perspective.

    Directory of Open Access Journals (Sweden)

    Yusuke Yamanoue

    Full Text Available Pufferfishes of the Family Tetraodontidae are the most speciose group in the Order Tetraodontiformes and mainly inhabit coastal waters along continents. Although no members of other tetraodontiform families have fully discarded their marine lives, approximately 30 tetraodontid species spend their entire lives in freshwaters in disjunct tropical regions of South America, Central Africa, and Southeast Asia. To investigate the interrelationships of tetraodontid pufferfishes and thereby elucidate the evolutionary origins of their freshwater habitats, we performed phylogenetic analysis based on whole mitochondrial genome sequences from 50 tetraodontid species and closely related species (including 31 newly determined sequences. The resulting phylogenies reveal that the family is composed of four major lineages and that freshwater species from the different continents are independently nested in two of the four lineages. A monophyletic origin of the use of freshwater habitats was statistically rejected, and ancestral habitat reconstruction on the resulting tree demonstrates that tetraodontids independently entered freshwater habitats in different continents at least three times. Relaxed molecular-clock Bayesian divergence time estimation suggests that the timing of these invasions differs between continents, occurring at 0-10 million years ago (MA in South America, 17-38 MA in Central Africa, and 48-78 MA in Southeast Asia. These timings are congruent with geological events that could facilitate adaptation to freshwater habitats in each continent.

  11. Salmonella infection in green anoles (Anolis carolinensis), an invasive alien species on Chichi Island of the Ogasawara archipelago in Japan.

    Science.gov (United States)

    Sumiyama, Daisuke; Izumiya, Hidemasa; Kanazawa, Tomoko; Murata, Koichi

    2014-03-01

    We investigated the presence of Salmonella in the green anole (Anolis carolinensis), an invasive alien species on Chichi Island, Japan. Samples were also collected from feral goats and public toilets on the island to examine infectious routes. Salmonellae were isolated from 27.1% of 199 samples; 32.6% of 141 cloacal samples from anoles, 62.5% of 8 intestinal samples from anole carcasses, 16.7% of 12 fecal samples from goats and 2.6% of 38 toilet bowl swabs. The serotype of most isolates was Salmonella Oranienburg (94.4% of 54). Although we did not confirm the infection pathways, our results indicated that green anoles are a risk factor as a source of Salmonella for public health. It is important to consider endemic pathogens that may be amplified by alien species within their introduced areas.

  12. 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.

  13. 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...

  14. Response measures of invasive alien species%外来生物入侵及应对措施

    Institute of Scientific and Technical Information of China (English)

    张凌峰

    2015-01-01

    Taking the biological invasion in The Kunming World Horticultural Expo Garden as example, this article analyzes in detail the causes of biological invasion and control measures. Results of the research provide a reference to alien biological invasion prevention and eco-security studies for Kunming World expo garden as well as the whole area of Kunming.%以昆明世界园艺博览园(以下简称世博园)内生物入侵的现状为例,分析其产生原因及防治对策,为世博园及整个昆明地区外来生物入侵的防范和生态安全提供参考。

  15. 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

    Alien plants are a growing threat to the Gala´pagos unique biota. We evaluated the impact of alien plants on eight seed dispersal networks from two islands of the archipelago. Nearly 10 000 intact seeds from 58 species were recovered from the droppings of 18 bird and reptile dispersers. The most...... plants were dispersed via two pathways: dryfruited plants were preferentially dispersed by finches, while fleshy fruited species were mostly dispersed by other birds and reptiles....

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

    OpenAIRE

    Heleno, Rubén H.; Olesen, Jens M.; Nogales, Manuel; Vargas, Pablo; Traveset, Anna

    2013-01-01

    Alien plants are a growing threat to the Galápagos unique biota. We evaluated the impact of alien plants on eight seed dispersal networks from two islands of the archipelago. Nearly 10 000 intact seeds from 58 species were recovered from the droppings of 18 bird and reptile dispersers. The most dispersed invaders were Lantana camara, Rubus niveus and Psidium guajava, the latter two likely benefiting from an asynchronous fruit production with most native plants, which facilitate their consumpt...

  17. No evidence for local adaptation in an invasive alien plant: field and greenhouse experiments tracing a colonization sequence.

    Science.gov (United States)

    Pahl, Anna T; Kollmann, Johannes; Mayer, Andreas; Haider, Sylvia

    2013-12-01

    Local adaptation enables plant species to persist under different environmental conditions. Evolutionary change can occur rapidly in invasive annual species and has been shown to lead to local adaptation. However, the patterns and mechanisms of local adaptation in invasive species along colonization sequences are not yet understood. Thus, in this study the alien annual Impatiens glandulifera was used to investigate local adaptation to distinct habitats that have been consecutively invaded in central Europe. A reciprocal transplant experiment was performed using 15 populations from alluvial deciduous forests, fallow meadows and coniferous upland forests, and a greenhouse experiment was performed in which plants from these habitats were grown under treatments reflecting the main habitat differentiators (shade, soil acidity, competition). Biomass production, specific leaf area, plant height and relative growth rate differed between habitats in the field experiment and between treatments in the greenhouse, but not between seed origins. Overall, there was no indication of local adaptation in either experiment. Since I. glandulifera is a successful invader in many habitats without showing local adaptation, it is suggested that the species is coping with environmental variation by means of high phenotypic plasticity. The species seems to follow a 'jack-and-master' strategy, i.e. it is able to maintain high fitness under a wide range of environmental conditions, but performs particularly well in favourable habitats. Therefore, the proposed colonization sequence is likely to be based primarily on changes in propagule pressure. It is concluded that invasive alien plants can become dominant in distinct habitats without local adaptation.

  18. Invasion of Nostocales (cyanobacteria) to Subtropical and Temperate Freshwater Lakes - Physiological, Regional, and Global Driving Forces.

    Science.gov (United States)

    Sukenik, Assaf; Hadas, Ora; Kaplan, Aaron; Quesada, Antonio

    2012-01-01

    Similar to the increased number of studies on invasive plants and animals in terrestrial and aquatic ecosystems, many reports were recently published on the invasion of Nostocales (cyanobacteria) to freshwater environments worldwide. Invasion and proliferation of Nostocales in new habitats have the potential to significantly alter the structure of the native community and to modify ecosystem functioning. But most importantly, they influence the water quality due to a variety of toxic compounds that some species produce. Therefore a special attention was given to the invasion and persistence of toxic cyanobacteria in many aquatic ecosystems. Here we summarize the currently published records on the invasion of two Nostocales genera, Cylindrospermopsis and Aphanizomenon, to lakes and water reservoirs in subtropical and temperate zones. These invading species possess traits thought to be common to many invasive organisms: high growth rate, high resource utilization efficiency and overall superior competitive abilities over native species when local conditions vary. Assuming that dispersion routes of cyanobacteria have not been changed much in recent decades, their recent establishment and proliferation in new habitats indicate changes in the environment under which they can exploit their physiological advantage over the native phytoplankton population. In many cases, global warming was identified as the major driving force for the invasion of Nostocales. Due to this uncontrollable trend, invasive Nostocales species are expected to maintain their presence in new habitats and further expand to new environments. In other cases, regional changes in nutrient loads and in biotic conditions were attributed to the invasion events.

  19. First occurrence of the invasive alien species Polydora cornuta Bosc, 1802 (Polychaeta: Spionidae on the coast of Greece (Elefsis Bay; Aegean Sea

    Directory of Open Access Journals (Sweden)

    N. SIMBOURA

    2012-12-01

    Full Text Available The present study reports on the occurrence of two specimens of the alien species Polydora cornutaBosc, 1802, in Elefsis Bay, the Saronikos Gulf (Aegean Sea, eastern Mediterranean. This is the firstrecord of this invasive alien species on the coast of Greece and the second report in the eastern MediterraneanSea after its first finding in Izmir Bay (on the Turkish Aegean coast. This finding enhances its distributionalpattern within the Mediterranean

  20. 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 projects were implemented, the costs per unit of water ?produced? would be lower when such projects were in place (van Wilgen et al. 1996); G investing in the management of invasive alien species in the catchments of existing dams would deliver water..., 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...

  1. 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

  2. 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.

  3. 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 incl

  4. Invasive alien plants in the terrestrial ecosystems of Natal, South Africa

    CSIR Research Space (South Africa)

    Macdonald, IAW

    1985-01-01

    Full Text Available This report consists of two types of chapters. Most of the chapters are short syntheses of particular aspects of the alien plant problem in Natal, written by groups of participants during the workshop meeting. They are brief accounts of the state...

  5. No evidence for local adaptation in an invasive alien plant: field and greenhouse experiments tracing a colonization sequence

    Science.gov (United States)

    Pahl, Anna T.; Kollmann, Johannes; Mayer, Andreas; Haider, Sylvia

    2013-01-01

    Background and Aims Local adaptation enables plant species to persist under different environmental conditions. Evolutionary change can occur rapidly in invasive annual species and has been shown to lead to local adaptation. However, the patterns and mechanisms of local adaptation in invasive species along colonization sequences are not yet understood. Thus, in this study the alien annual Impatiens glandulifera was used to investigate local adaptation to distinct habitats that have been consecutively invaded in central Europe. Methods A reciprocal transplant experiment was performed using 15 populations from alluvial deciduous forests, fallow meadows and coniferous upland forests, and a greenhouse experiment was performed in which plants from these habitats were grown under treatments reflecting the main habitat differentiators (shade, soil acidity, competition). Key Results Biomass production, specific leaf area, plant height and relative growth rate differed between habitats in the field experiment and between treatments in the greenhouse, but not between seed origins. Overall, there was no indication of local adaptation in either experiment. Conclusions Since I. glandulifera is a successful invader in many habitats without showing local adaptation, it is suggested that the species is coping with environmental variation by means of high phenotypic plasticity. The species seems to follow a ‘jack-and-master’ strategy, i.e. it is able to maintain high fitness under a wide range of environmental conditions, but performs particularly well in favourable habitats. Therefore, the proposed colonization sequence is likely to be based primarily on changes in propagule pressure. It is concluded that invasive alien plants can become dominant in distinct habitats without local adaptation. PMID:24214934

  6. Synergistic impacts by an invasive amphipod and an invasive fish explain native gammarid extinction

    OpenAIRE

    Beggel, S.; Brandner, J.; Cerwenka, A. F.; Geist, J.

    2016-01-01

    Background Worldwide freshwater ecosystems are increasingly affected by invasive alien species. In particular, Ponto-Caspian gobiid fishes and amphipods are suspected to have pronounced effects on aquatic food webs. However, there is a lack of systematic studies mechanistically testing the potential synergistic effects of invasive species on native fauna. In this study we investigated the interrelations between the invasive amphipod Dikerogammarus villosus and the invasive fish species Neogob...

  7. Calibration of FISK, an invasiveness screening tool for nonnative freshwater fishes.

    Science.gov (United States)

    Copp, Gordon H; Vilizzi, Lorenzo; Mumford, John; Fenwick, Gemma V; Godard, Michael J; Gozlan, Rodolphe E

    2009-03-01

    Adapted from the weed risk assessment (WRA) of Pheloung, Williams, and Halloy, the fish invasiveness scoring kit (FISK) was proposed as a screening tool for freshwater fishes. This article describes improvements to FISK, in particular the incorporation of confidence (certainty/uncertainty) ranking of the assessors' responses, and reports on the calibration of the score system, specifically: determination of most appropriate score thresholds for classifying nonnative species into low-, medium-, and high-risk categories, assessment of the patterns of assessors' confidences in their responses in the FISK assessments. Using receiver operating characteristic (ROC) curves, FISK was demonstrated to distinguish accurately (and with statistical confidence) between potentially invasive and noninvasive species of nonnative fishes, with the statistically appropriate threshold score for high-risk species scores being >/=19. Within the group of species classed as high risk using this new threshold, a "higher risk" category could be visually identified, at present consisting of two species (topmouth gudgeon Pseudorasbora parva and gibel carp Carassius gibelio). FISK represents a useful and viable tool to aid decision- and policymakers in assessing and classifying freshwater fishes according to their potential invasiveness.

  8. Studies on Legislation of Preventing and Controlling of Invasive Alien Species%防治外来物种入侵立法研究

    Institute of Scientific and Technical Information of China (English)

    刘欣庆; 李景明; 孙玉芳

    2012-01-01

    With the rapid economic development as well as continuously strengthening of international exchanges, the invasion of alien species is becoming increasingly serious and caused significant harm to the country's economic, cultural, ecological and human health. By analysis of legislation of international community for preventing and controlling invasive alien species, China's legislative problems of preventing and controlling invasive alien species were studied. Suggestions to modify current laws and regulations were proposed for comprehensive construction of China's legislation of prevention and control of alien invasive species.%随着经济的快速发展以及国际交流的不断加强,外来物种入侵的现象日益严重,给我国的经济、文化、生态以及人类健康造成了重大的危害。文章通过分析国际社会外来物种入侵立法情况,研究了我国在防治外来物种入侵立法方面存在的问题,并对现有法律法规中的有关内容提出了修改和完善的建议,以期为全面加强我国防治外来物种入侵立法提供借鉴。

  9. Comparison of water-use by alien invasive pine trees growing in riparian and non-riparian zones in the Western Cape Province, South Africa

    CSIR Research Space (South Africa)

    Dzikiti, Sebinasi

    2013-04-01

    Full Text Available Self-established stands of alien invasive pine trees are common in many parts of South Africa and elsewhere. They mainly invade non-riparian settings but sometimes invade riparian habitats. There are clear visual differences in the physical...

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. Does mutualism drive the invasion of two alien species? The case of Solenopsis invicta and Phenacoccus solenopsis.

    Directory of Open Access Journals (Sweden)

    Aiming Zhou

    Full Text Available 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

  15. Freshwater wetlands: fertile grounds for the invasive Phragmites australis in a climate change context

    Science.gov (United States)

    Tougas-Tellier, Marie-Andrée; Morin, Jean; Hatin, Daniel; Lavoie, Claude

    2015-01-01

    Climate change will likely affect flooding regimes, which have a large influence on the functioning of freshwater riparian wetlands. Low water levels predicted for several fluvial systems make wetlands especially vulnerable to the spread of invaders, such as the common reed (Phragmites australis), one of the most invasive species in North America. We developed a model to map the distribution of potential germination grounds of the common reed in freshwater wetlands of the St. Lawrence River (Québec, Canada) under current climate conditions and used this model to predict their future distribution under two climate change scenarios simulated for 2050. We gathered historical and recent (remote sensing) data on the distribution of common reed stands for model calibration and validation purposes, then determined the parameters controlling the species establishment by seed. A two-dimensional model and the identified parameters were used to simulate the current (2010) and future (2050) distribution of germination grounds. Common reed stands are not widespread along the St. Lawrence River (212 ha), but our model suggests that current climate conditions are already conducive to considerable further expansion (>16,000 ha). Climate change may also exacerbate the expansion, particularly if river water levels drop, which will expose large bare areas propitious to seed germination. This phenomenon may be particularly important in one sector of the river, where existing common reed stands could increase their areas by a factor of 100, potentially creating the most extensive reedbed complex in North America. After colonizing salt and brackishwater marshes, the common reed could considerably expand into the freshwater marshes of North America which cover several million hectares. The effects of common reed expansion on biodiversity are difficult to predict, but likely to be highly deleterious given the competitiveness of the invader and the biological richness of freshwater

  16. Freshwater wetlands: fertile grounds for the invasive Phragmites australis in a climate change context.

    Science.gov (United States)

    Tougas-Tellier, Marie-Andrée; Morin, Jean; Hatin, Daniel; Lavoie, Claude

    2015-08-01

    Climate change will likely affect flooding regimes, which have a large influence on the functioning of freshwater riparian wetlands. Low water levels predicted for several fluvial systems make wetlands especially vulnerable to the spread of invaders, such as the common reed (Phragmites australis), one of the most invasive species in North America. We developed a model to map the distribution of potential germination grounds of the common reed in freshwater wetlands of the St. Lawrence River (Québec, Canada) under current climate conditions and used this model to predict their future distribution under two climate change scenarios simulated for 2050. We gathered historical and recent (remote sensing) data on the distribution of common reed stands for model calibration and validation purposes, then determined the parameters controlling the species establishment by seed. A two-dimensional model and the identified parameters were used to simulate the current (2010) and future (2050) distribution of germination grounds. Common reed stands are not widespread along the St. Lawrence River (212 ha), but our model suggests that current climate conditions are already conducive to considerable further expansion (>16,000 ha). Climate change may also exacerbate the expansion, particularly if river water levels drop, which will expose large bare areas propitious to seed germination. This phenomenon may be particularly important in one sector of the river, where existing common reed stands could increase their areas by a factor of 100, potentially creating the most extensive reedbed complex in North America. After colonizing salt and brackishwater marshes, the common reed could considerably expand into the freshwater marshes of North America which cover several million hectares. The effects of common reed expansion on biodiversity are difficult to predict, but likely to be highly deleterious given the competitiveness of the invader and the biological richness of freshwater

  17. Legal immigrants: invasion of alien microbial communities during winter occurring desert dust storms.

    Science.gov (United States)

    Weil, Tobias; De Filippo, Carlotta; Albanese, Davide; Donati, Claudio; Pindo, Massimo; Pavarini, Lorenzo; Carotenuto, Federico; Pasqui, Massimiliano; Poto, Luisa; Gabrieli, Jacopo; Barbante, Carlo; Sattler, Birgit; Cavalieri, Duccio; Miglietta, Franco

    2017-03-10

    A critical aspect regarding the global dispersion of pathogenic microorganisms is associated with atmospheric movement of soil particles. Especially, desert dust storms can transport alien microorganisms over continental scales and can deposit them in sensitive sink habitats. In winter 2014, the largest ever recorded Saharan dust event in Italy was efficiently deposited on the Dolomite Alps and was sealed between dust-free snow. This provided us the unique opportunity to overcome difficulties in separating dust associated from "domestic" microbes and thus, to determine with high precision microorganisms transported exclusively by desert dust. Our metagenomic analysis revealed that sandstorms can move not only fractions but rather large parts of entire microbial communities far away from their area of origin and that this microbiota contains several of the most stress-resistant organisms on Earth, including highly destructive fungal and bacterial pathogens. In particular, we provide first evidence that winter-occurring dust depositions can favor a rapid microbial contamination of sensitive sink habitats after snowmelt. Airborne microbial depositions accompanying extreme meteorological events represent a realistic threat for ecosystem and public health. Therefore, monitoring the spread and persistence of storm-travelling alien microbes is a priority while considering future trajectories of climatic anomalies as well as anthropogenically driven changes in land use in the source regions.

  18. 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...

  19. 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

    2015-01-01

    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 a

  20. Double blow: Alien crayfish infected with invasive temnocephalan in South African waters

    Directory of Open Access Journals (Sweden)

    Louis du Preez

    2013-09-01

    Full Text Available Trade in live, freshwater crayfish for ornamental markets, as well as for aquaculture, has grown rapidly and has become the major pathway for the introduction of non-indigenous crayfish species to several countries worldwide. Here we report on the first record of the Australian "redclaw" Cherax quadracarinatus in the natural waters of a game reserve in South Africa. To compound the situation, these redclaw crayfish were infected with a non-indigenous temnocephalan flatworm parasite. Both crayfish and temnocephalan were in full breeding condition, with young. Further spreading of this crayfish to the subtropical, water-rich, northern KwaZulu-Natal Province of South Africa and southern Mozambique is predicted. Not only might the crayfish compete with indigenous aquatic invertebrates but the non-host-specific temnocephalan might transfer to local decapods, such as freshwater crabs.

  1. 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 measurable criteria for assessing the success of restoration. Climate change could significantly exacerbate problems with invasive species and work is needed to accommodate plausible trajectories in planning and management frameworks. Perhaps the greatest...

  2. Past and estimated future impact of invasive alien mammals on insular threatened vertebrate populations.

    Science.gov (United States)

    McCreless, Erin E; Huff, David D; Croll, Donald A; Tershy, Bernie R; Spatz, Dena R; Holmes, Nick D; Butchart, Stuart H M; Wilcox, Chris

    2016-08-18

    Invasive mammals on islands pose severe, ongoing threats to global biodiversity. However, the severity of threats from different mammals, and the role of interacting biotic and abiotic factors in driving extinctions, remain poorly understood at a global scale. Here we model global extirpation patterns for island populations of threatened and extinct vertebrates. Extirpations are driven by interacting factors including invasive rats, cats, pigs, mustelids and mongooses, native species taxonomic class and volancy, island size, precipitation and human presence. We show that controlling or eradicating the relevant invasive mammals could prevent 41-75% of predicted future extirpations. The magnitude of benefits varies across species and environments; for example, managing invasive mammals on small, dry islands could halve the extirpation risk for highly threatened birds and mammals, while doing so on large, wet islands may have little benefit. Our results provide quantitative estimates of conservation benefits and, when combined with costs in a return-on-investment framework, can guide efficient conservation strategies.

  3. Study on the Invasive Alien Plants in South China%华南地区外来人侵植物调查研究

    Institute of Scientific and Technical Information of China (English)

    林建勇; 梁瑞龙; 李娟; 黄应钦

    2012-01-01

    根据野外调查和相关资料整理,探讨华南地区入侵植物的种类组成、来源、生长型,比较不同地区间种类组成的相似性,预测部分危险性较大的入侵种的扩散趋势。研究表明:华南三省共有外来入侵植物148种,属于41科105属,其中广东、广西、海南分别为132、129、100种,以菊科(Asteraceae)、禾本科(Gramineae)和苋科(Amaranthaceae)的种类最多。美洲起源的入侵种最多,共有108种,占总种数73.0%。草本型入侵植物种类最多,共有114种,占总物种数77.0%。广东和广西两省入侵植物组成的相似性最大,广西和海南的相似性最低。%According to field investigation and relative data, the species composition, origin and life form were studied, the similarity of different species in different areas was compared, and the spread- ing tendency on part of high dangerous invasive alien plants was predicted. The study showed that 148 species of invasive alien plants belonging to 105 genera of 41 families were identified in three provinces of South China. There were 132 species of invasive alien plants in Guangdong, 129 species in Guangxi and 100 species in Hainan, in which the most were Asteraceae, Gramineae and Amaranthaceae. The most of the invasive alien plants were from America with 108 species, taking up 73.0% of the total species. The species of herbaceous invasive alien plants were the most with 114 species, taking up 77.0 %. The similarity of species composition of invasive alien plants between Guangdong and Guangxi was the highest, the lowest between Guangxi and Hainan.

  4. Alien freshwater polychaetes Hypania invalida (Grube 1860 and Laonome calida Capa 2007 in the Upper Odra River (Baltic Sea catchment area

    Directory of Open Access Journals (Sweden)

    Pabis Krzysztof

    2017-01-01

    Full Text Available Two polychaete species, Hypania invalida and Laonome calida, were found in the Upper Odra River in 2016. Both species were recorded close to a natural river bank down to 1 m depths. They inhabited sandy-gravelly and sandy-muddy sediments. H. invalida is an alien invasive Ponto-Caspian species, previously known in Poland from the Odra River estuary only. Our results may indicate a further rapid dispersal of H. invalida upstream the Odra River or an accidental introduction. This study is the first record of L. calida in the Baltic Sea catchment. This Australian species has been recently introduced into Europe. Prior to this study, it had been reported from Dutch rivers only. The present data suggest accidental introduction of the species to European rivers; however, our findings show an urgent need for a close monitoring of the polychaete in Europe.

  5. 历山自然保护区外来入侵植物研究%Study on Invasive Alien Plants in Lishan Nature Reserve, Shanxi

    Institute of Scientific and Technical Information of China (English)

    马世军; 王建军

    2011-01-01

    The invasive alien plants in Lishan Nature Reserve, Shanxi, totally 11 species, were studied,including Chenopodium hybridum ,Amaranthus retroflexus ,Vaccaria segetalis ,Melilotus albus , Hibisicus trio-num , Ipomoea purpurea ,Datura stramonium ,Conyza Canadensis ,Erigeron annuus ,Sonchus oleraceus and Avena fatua. The diffusing mechanism, invasion route, distribution, habitat, ecological damage and utilization value for those invasive alien plants were analyzed,respectively. Moreover,the management strategies for those invasive alien species were also discussed, including mechanical, chemical and biological controls and strengthening research of diffusing mechanism.%历山自然保护区的外来入侵植物有11种,分别是杂配藜、反枝苋、王不留行、白香草木樨、野西瓜苗、圆叶牵牛、曼陀罗、小蓬草、一年蓬、苦苣菜、野燕麦等.本文论述了它们的入侵途径、分布、生境、危害及利用价值,提出了对外来入侵植物的管理对策,包括人工措施、化学措施、生物措施、加强扩散机制研究等.

  6. Absence of sterols constrains food quality of cyanobacteria for an invasive freshwater bivalve.

    Science.gov (United States)

    Basen, Timo; Rothhaupt, Karl-Otto; Martin-Creuzburg, Dominik

    2012-09-01

    The accumulation of cyanobacterial biomass may severely affect the performance of aquatic consumers. Here, we investigated the role of sterols in determining the food quality of cyanobacteria for the invasive clam Corbicula fluminea, which has become a common benthic invertebrate in many freshwater ecosystems throughout the world. In standardized growth experiments, juvenile clams were fed mixtures of different cyanobacteria (Anabaena variabilis, Aphanothece clathrata, Synechococcus elongatus) or sterol-containing eukaryotic algae (Cryptomonas sp., Nannochloropsis limnetica, Scenedesmus obliquus). In addition, the cyanobacterial food was supplemented with different sterols. We provide evidence that somatic growth of C. fluminea on cyanobacterial diets is constrained by the absence of sterols, as indicated by a growth-enhancing effect of sterol supplementation. Thus, our findings contribute to our understanding of the consequences of cyanobacterial mass developments for benthic consumers and highlight the importance of considering sterols as potentially limiting nutrients in aquatic food webs.

  7. Past and estimated future impact of invasive alien mammals on insular threatened vertebrate populations

    Science.gov (United States)

    McCreless, Erin E.; Huff, David D.; Croll, Donald A.; Tershy, Bernie R.; Spatz, Dena R.; Holmes, Nick D.; Butchart, Stuart H. M.; Wilcox, Chris

    2016-01-01

    Invasive mammals on islands pose severe, ongoing threats to global biodiversity. However, the severity of threats from different mammals, and the role of interacting biotic and abiotic factors in driving extinctions, remain poorly understood at a global scale. Here we model global extirpation patterns for island populations of threatened and extinct vertebrates. Extirpations are driven by interacting factors including invasive rats, cats, pigs, mustelids and mongooses, native species taxonomic class and volancy, island size, precipitation and human presence. We show that controlling or eradicating the relevant invasive mammals could prevent 41–75% of predicted future extirpations. The magnitude of benefits varies across species and environments; for example, managing invasive mammals on small, dry islands could halve the extirpation risk for highly threatened birds and mammals, while doing so on large, wet islands may have little benefit. Our results provide quantitative estimates of conservation benefits and, when combined with costs in a return-on-investment framework, can guide efficient conservation strategies. PMID:27535095

  8. 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 af

  9. Antagonistic effects of biological invasion and environmental warming on detritus processing in freshwater ecosystems.

    Science.gov (United States)

    Kenna, Daniel; Fincham, William N W; Dunn, Alison M; Brown, Lee E; Hassall, Christopher

    2017-03-01

    Global biodiversity is threatened by multiple anthropogenic stressors but little is known about the combined effects of environmental warming and invasive species on ecosystem functioning. We quantified thermal preferences and then compared leaf-litter processing rates at eight different temperatures (5.0-22.5 °C) by the invasive freshwater crustacean Dikerogammarus villosus and the Great Britain native Gammarus pulex at a range of body sizes. D. villosus preferred warmer temperatures but there was considerable overlap in the range of temperatures that the two species occupied during preference trials. When matched for size, G. pulex had a greater leaf shredding efficiency than D. villosus, suggesting that invasion and subsequent displacement of the native amphipod will result in reduced ecosystem functioning. However, D. villosus is an inherently larger species and interspecific variation in shredding was reduced when animals of a representative size range were compared. D. villosus shredding rates increased at a faster rate than G. pulex with increasing temperature suggesting that climate change may offset some of the reduction in function. D. villosus, but not G. pulex, showed evidence of an ability to select those temperatures at which its shredding rate was maximised, and the activation energy for shredding in D. villosus was more similar to predictions from metabolic theory. While per capita and mass-corrected shredding rates were lower in the invasive D. villosus than the native G. pulex, our study provides novel insights in to how the interactive effects of metabolic function, body size, behavioural thermoregulation, and density produce antagonistic effects between anthropogenic stressors.

  10. 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 secondary driving forces ? Human population growth and migration Population increases lead to greater demands for food and materials. These demands are met by increasing productivity throughfertilization,adoptionofnewspecies,andbyincreasing the area under... production.1,35,37,48 Where demands cannot be met, people tend to migrate, taking propagules of their custom- ary food and medicinal plant species with them31,49 and inadver- tently carrying invasive species. ? Expanding network of international trade...

  11. Hybridization and Sexual Reproduction in the Invasive Alien Fallopia (Polygonaceae) Complex in Belgium

    Science.gov (United States)

    Tiébré, Marie-Solange; Vanderhoeven, Sonia; Saad, Layla; Mahy, Grégory

    2007-01-01

    Background and Aims The knotweed complex, Fallopia spp. (Polygonaceae), belongs to the most troublesome invasive species in Europe and North America. Vegetative regeneration is widely recognized as the main mode of reproduction in the adventive regions. However, the contribution of sexual reproduction to the success of these invasive species has only been detailed for the British Isles. An examination was made as to how hybridization may influence the sexual reproduction of the complex in Belgium and to determine how it may contribute to the dispersal of the species. Methods Studies were made of floral biology, reproductive success, seed rain, seed bank, germination capacity, seedling survival and dispersal capacity in order to characterize the reproductive biology of the species. Moreover, chromosome counts and flow cytometry were used to assess the hybrid status of seedlings produced by sexual reproduction. Key Results In the area investigated, extensive sexual reproduction by hybridization within the complex, including one horticultural species, was demonstrated. A small percentage of seeds may be dispersed outside the maternal clone (>16 m) allowing the formation of genetically differentiated individuals. Seed germination was possible even after a winter cold period. Conclusions The extensive sexual reproduction by hybridization could further contribute to the dramatic invasive success of knotweeds in Belgium and should not be underestimated when considering control and management measures. PMID:17210609

  12. 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.

  13. Is there a need for a more explicit accounting of invasive alien species under the Water Framework Directive?

    Directory of Open Access Journals (Sweden)

    Jochen Vandekerkhove

    2013-01-01

    Full Text Available Through ratification of the Water Framework Directive (WFD, EU Member States committed themselves to a pressure-based assessment ofthe ecological status of their water bodies. Invasive alien species (IAS constitute a major pressure in many aquatic ecosystems, yet are notexplicitly accounted for by the majority of WFD assessment methods. Most Member States argue that no explicit assessment of IAS isrequired, assuming that significant IAS pressures will affect the WFD biological quality elements (BQEs, and be detected by generic WFDstatus assessments. We tested this assumption for a selection of country-by-surface-water category combinations, covering nearly 40,000water bodies. For each of the combinations, the pressure by high-impact IAS is higher in water bodies with ecological status varying from bad to moderate than in water bodies in good or high ecological status. Most high-impact IAS show strong associations with low status class categories. Of the 17 most frequently occurring high-impact IAS, only Mustela vison (Schreber, 1777 and Potamopyrgus antipodarum(Gray, 1853 are disproportionately frequent in high status water bodies. The sensitivity of WFD methods varies across BQEs, withmacrophyte-based methods showing a consistently high sensitivity to IAS pressures. However, significant pressures are observed in anumber of high status water bodies. This points to a need for further optimization of existing methods so that they address the full range of pressures exerted by IAS.

  14. A review of invasive alien species impacts on eucalypt stands and citrus orchards ecosystem services: towards an integrated management approach.

    Science.gov (United States)

    Branco, Sofia; Videira, Nuno; Branco, Manuela; Paiva, Maria Rosa

    2015-02-01

    Multidisciplinary knowledge on the impact caused by invasive alien species (IAS) on ecosystems is crucial for guiding policy makers in the adoption of sustainable management measures. This research was focused on insect IAS impacts on two managed ecosystems: eucalypt plantations and citrus orchards. It begins with an identification of the wide range of ecosystem services (ES) and disservices provided by each of these managed ecosystems, according to the methodology proposed by the Millennium Ecosystem Assessment. Subsequently, a comprehensive review of studies that promoted the identification and valuation of direct and indirect impacts IAS impacts on these ecosystems was performed. From the synthesis of previous findings, an integrative management framework is advanced. This links the identification of ES, drivers of change and development of IAS management strategies by means of assessment processes that account for multiple dimensions of ES values. The article concludes with a discussion on the challenges underpinning assessment and valuation approaches that inform the design of inclusive strategies and interventions to tackle IAS impacts. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Plant-associated bacterial populations on native and invasive plant species: comparisons between 2 freshwater environments.

    Science.gov (United States)

    Olapade, Ola A; Pung, Kayleigh

    2012-06-01

    Plant-microbial interactions have been well studied because of the ecological importance of such relationships in aquatic systems. However, general knowledge regarding the composition of these biofilm communities is still evolving, partly as a result of several confounding factors that are attributable to plant host properties and to hydrodynamic conditions in aquatic environments. In this study, the occurrences of various bacterial phylogenetic taxa on 2 native plants, i.e., mayapple (Podophyllum peltatum L.) and cow parsnip (Heracleum maximum Bartram), and on an invasive species, i.e., garlic mustard (Alliaria petiolata (M. Bieb.) Cavara & Grande), were quantitatively examined using nucleic acid staining and fluorescence in situ hybridization. The plants were incubated in triplicates for about a week within the Kalamazoo River and Pierce Cedar Creek as well as in microcosms. The bacterial groups targeted for enumeration are known to globally occur in relatively high abundance and are also ubiquitously distributed in freshwater environments. Fluorescence in situ hybridization analyses of the bacterioplankton assemblages revealed that the majority of bacterial cells that hybridized with the different probes were similar between the 2 sites. In contrast, the plant-associated populations while similar on the 3 plants incubated in Kalamazoo River, their representations were highest on the 2 native plants relative to the invasive species in Pierce Cedar Creek. Overall, our results further suggested that epiphytic bacterial assemblages are probably under the influences of and probably subsequently respond to multiple variables and conditions in aquatic milieus.

  16. Neighbour Origin and Ploidy Level Drive Impact of an Alien Invasive Plant Species in a Competitive Environment.

    Science.gov (United States)

    Sun, Yan; Müller-Schärer, Heinz; Schaffner, Urs

    2016-01-01

    Our understanding of the potential mechanisms driving the spread and naturalization of alien plant species has increased over the past decades, but specific knowledge on the factors contributing to their increased impact in the introduced range is still urgently needed. The native European plant Centaurea stoebe occurs as two cytotypes with different life histories (monocarpic diploids, allo-polycarpic tetraploids). However, only tetraploids have been found in its introduced range in North America, where C. stoebe has become a most prominent plant invader. Here, we focus on the ploidy level of C. stoebe and origin of neighbouring community in explaining the high impact during the invasion of new sites in the introduced range. We conducted a mesocosm experiment under open-field conditions with the diploid (EU2x) and tetraploid (EU4x) cytotype of Centaurea stoebe from its native European (EU) range, and with the invasive tetraploid (NA4x) cytotype from the introduced North American (NA) range in competition with EU (old) or NA (new) neighbouring plant communities. In the presence of competition, the biomass of EU neighbouring community was reduced to a comparable level by all three geo-cytotypes of C. stoebe. In contrast, the biomass of the NA neighbouring community was reduced beyond when competing with tetraploid, but not with diploid C. stoebe. The fact that the biomass of all three geo-cytotypes of C. stoebe was correlated with the biomass of the EU neighbouring community, but not with that of the NA neighbouring community suggests that different mechanisms underlie the competitive interactions between C. stoebe and its old vs. new neighbouring communities, such as competition for the same limiting resources at home vs competition through novel allelo-chemicals or differential resource uptake strategies in the introduced range. We therefore caution to simply use the ecosystem impact assessed at home to predict impact in the introduced range.

  17. Root-inhabiting fungi in alien plant species in relation to invasion status and soil chemical properties.

    Science.gov (United States)

    Majewska, Marta L; Błaszkowski, Janusz; Nobis, Marcin; Rola, Kaja; Nobis, Agnieszka; Łakomiec, Daria; Czachura, Paweł; Zubek, Szymon

    In order to recognize interactions between alien vascular plants and soil microorganisms and thus better understand the mechanisms of plant invasions, we examined the mycorrhizal status, arbuscular mycorrhizal fungi (AMF) colonization rate, arbuscular mycorrhiza (AM) morphology and presence of fungal root endophytes in 37 non-native species in Central Europe. We also studied the AMF diversity and chemical properties of soils from under these species. The plant and soil materials were collected in southern Poland. We found that 35 of the species formed AM and their mycorrhizal status depended on species identity. Thirty-three taxa had AM of Arum-type alone. Lycopersicon esculentum showed intermediate AM morphology and Eragrostis albensis developed both Arum and Paris. The mycelia of dark septate endophytes (DSE) were observed in 32 of the species, while sporangia of Olpidium spp. were found in the roots of 10. Thirteen common and worldwide occurring AMF species as well as three unidentified spore morphotypes were isolated from trap cultures established with the soils from under the plant species. Claroideoglomus claroideum, Funneliformis mosseae and Septoglomus constrictum were found the most frequently. The presence of root-inhabiting fungi and the intensity of their colonization were not correlated with soil chemical properties, plant invasion status, their local abundance and habitat type. No relationships were also found between the presence of AMF, DSE and Olpidium spp. These suggest that other edaphic conditions, plant and fungal species identity or the abundance of these fungi in soils might have an impact on the occurrence and intensity of fungal root colonization in the plants under study.

  18. 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)

  19. Neighbour Origin and Ploidy Level Drive Impact of an Alien Invasive Plant Species in a Competitive Environment.

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    Yan Sun

    Full Text Available Our understanding of the potential mechanisms driving the spread and naturalization of alien plant species has increased over the past decades, but specific knowledge on the factors contributing to their increased impact in the introduced range is still urgently needed. The native European plant Centaurea stoebe occurs as two cytotypes with different life histories (monocarpic diploids, allo-polycarpic tetraploids. However, only tetraploids have been found in its introduced range in North America, where C. stoebe has become a most prominent plant invader. Here, we focus on the ploidy level of C. stoebe and origin of neighbouring community in explaining the high impact during the invasion of new sites in the introduced range. We conducted a mesocosm experiment under open-field conditions with the diploid (EU2x and tetraploid (EU4x cytotype of Centaurea stoebe from its native European (EU range, and with the invasive tetraploid (NA4x cytotype from the introduced North American (NA range in competition with EU (old or NA (new neighbouring plant communities. In the presence of competition, the biomass of EU neighbouring community was reduced to a comparable level by all three geo-cytotypes of C. stoebe. In contrast, the biomass of the NA neighbouring community was reduced beyond when competing with tetraploid, but not with diploid C. stoebe. The fact that the biomass of all three geo-cytotypes of C. stoebe was correlated with the biomass of the EU neighbouring community, but not with that of the NA neighbouring community suggests that different mechanisms underlie the competitive interactions between C. stoebe and its old vs. new neighbouring communities, such as competition for the same limiting resources at home vs competition through novel allelo-chemicals or differential resource uptake strategies in the introduced range. We therefore caution to simply use the ecosystem impact assessed at home to predict impact in the introduced range.

  20. 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

  1. Density and temperature dependent feeding rates in an established and an alien freshwater gammarid fed on chironomid larvae

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    Dieter WALOSZEK

    2011-02-01

    Full Text Available We compared feeding rates of the well-established, non-invasive amphipod Gammarus roeselii with those of the invasive Dikerogammarus villosus at different prey densities and different temperatures in laboratory experiments using chironomid larvae as prey. Feeding rates were very variable in both species but higher in the invader species than in the well-established non-invasive species. These results were age independent. At high temperature (18-20 °C and high prey density (≥1000 prey m-2 one large adult D. villosus consumed 6-9 prey day-1 on average while one G. roeselii consumed 4-7 prey d-1 and one smaller D. villosus of a length of 8-10 mm consumed 2-5 prey d-1 while one G. roeselii of the same length consumed 3 prey d-1. Predation rate decreased considerably from high (18-20 °C to low temperature (3±2 °C, from 9 to 4 prey predator-1 d-1 in D. villosus and from 7.5 to 2.5 prey predator-1 d-1 in G. roeselii. We conclude that both gammarids consumed a biomass in the range of 1/2 to 1/3 to their own biomass and that low predation/feeding rate at low temperature could be a reason why, in some places, indigenous gammarids can re-colonize their former habitats for a short period of time in cold winter and early spring in spite of the presence of the invasive. We further conclude that differences in weight between the species in particular in the experiments with adults can have influenced feeding rates; possibly differences in weight- specific feeding rates are small.

  2. Invasive, naturalized and casual alien plants in southern Africa: a sum­mary based on the Southern African Plant Invaders Atlas (SAPIA

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    L. Henderson

    2007-12-01

    Full Text Available The primary objective of this publication is to provide an overview of the species identity, invasion status, geographical extent, and abundance of alien plants in South Africa, Swaziland and Lesotho, based on field records from 1979 to the end of 2000. The dataset is all the species records for the study area in the Southern African Plant Invaders Atlas (SAPIA database during this time period. A total of 548 naturalized and casual alien plant species were catalogued and invasion was recorded almost throughout the study area. Most invasion, in terms of both species numbers and total species abundance, was recorded along the southern, southwestern and eastern coastal belts and in the adjacent interior. This area includes the whole of the Fynbos and Forest Biomes, and the moister eastern parts of the Grassland and Savanna Biomes. This study reinforces previous studies that the Fynbos Biome is the most extensively invaded vegetation type in South Africa but it also shows that parts of Savanna and Grassland are as heavily invaded as parts of the Fynbos. The Fabaceae is prominent in all biomes and Acacia with 17 listed species, accounts for a very large proportion of all invasion. Acacia mearmii was by far the most prominent invasive species in the study area, followed by A. saligna, Lantana camara, A. cyclops, Opuntia ficus-indica. Solarium mauritianum, Populus alba/xcanescens, Melia azedarach, A. dealbata and species of Prosopis.

  3. 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.

  4. 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

    2013-01-01

    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. PMID:24363899

  5. 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

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

    Science.gov (United States)

    Forsyth, G G; Le Maitre, D C; O'Farrell, P J; van Wilgen, B W

    2012-07-30

    Invasions by alien plants are a significant threat to the biodiversity and functioning of ecosystems and the services they provide. The South African Working for Water program was established to address this problem. It needs to formulate objective and transparent priorities for clearing in the face of multiple and sometimes conflicting demands. This study used the analytic hierarchy process (a multi-criteria decision support technique) to develop and rank criteria for prioritising alien plant control 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 develop decision models) with data-driven model solutions enabled us to include many alternatives (water catchments), that would otherwise not have been feasible. The most important criteria included the capacity to maintain gains made through control operations, the potential to enhance water resources and conserve biodiversity, and threats from priority invasive alien plant species. We selected spatial datasets and used them to generate weights that could be used to objectively compare alternatives with respect to agreed criteria. The analysis showed that there are many high priority catchments which are not receiving any funding and low priority catchments which are receiving substantial allocations. Clearly, there is a need for realigning priorities, including directing sufficient funds to the highest priority catchments to provide effective control. This approach provided a tractable, consensus-based solution that can be used to direct clearing operations.

  7. Invasive species and habitat degradation in Iberian streams: an analysis of their role in freshwater fish diversity loss.

    Science.gov (United States)

    Hermoso, Virgilio; Clavero, Miguel; Blanco-Garrido, Francisco; Prenda, José

    2011-01-01

    Mediterranean endemic freshwater fish are among the most threatened biota in the world. Distinguishing the role of different extinction drivers and their potential interactions is crucial for achieving conservation goals. While some authors argue that invasive species are a main driver of native species declines, others see their proliferation as a co-occurring process to biodiversity loss driven by habitat degradation. It is difficult to discern between the two potential causes given that few invaded ecosystems are free from habitat degradation, and that both factors may interact in different ways. Here we analyze the relative importance of habitat degradation and invasive species in the decline of native fish assemblages in the Guadiana River basin (southwestern Iberian Peninsula) using an information theoretic approach to evaluate interaction pathways between invasive species and habitat degradation (structural equation modeling, SEM). We also tested the possible changes in the functional relationships between invasive and native species, measured as the per capita effect of invasive species, using ANCOVA. We found that the abundance of invasive species was the best single predictor of natives' decline and had the highest Akaike weight among the set of predictor variables examined. Habitat degradation neither played an active role nor influenced the per capita effect of invasive species on natives. Our analyses indicated that downstream reaches and areas close to reservoirs had the most invaded fish assemblages, independently of their habitat degradation status. The proliferation of invasive species poses a strong threat to the persistence of native assemblages in highly fluctuating environments. Therefore, conservation efforts to reduce native freshwater fish diversity loss in Mediterranean rivers should focus on mitigating the effect of invasive species and preventing future invasions.

  8. Evidence for shifts to faster growth strategies in the new ranges of invasive alien plants

    Science.gov (United States)

    Leishman, Michelle R; Cooke, Julia; Richardson, David M; Newman, Jonathan

    2014-01-01

    Summary Understanding the processes underlying the transition from introduction to naturalization and spread is an important goal of invasion ecology. Release from pests and pathogens in association with capacity for rapid growth is thought to confer an advantage for species in novel regions. We assessed leaf herbivory and leaf-level traits associated with growth strategy in the native and exotic ranges of 13 invasive plant species from 256 populations. Species were native to either the Western Cape region of South Africa, south-western Australia or south-eastern Australia and had been introduced to at least one of the other regions or to New Zealand. We tested for evidence of herbivore release and shifts in leaf traits between native and exotic ranges of the 13 species. Across all species, leaf herbivory, specific leaf area and leaf area were significantly different between native and exotic ranges while there were no significant differences across the 13 species found for leaf mass, assimilation rate, dark respiration or foliar nitrogen. Analysis at the species- and region-level showed that eight out of 13 species had reduced leaf herbivory in at least one exotic region compared to its native range. Six out of 13 species had significantly larger specific leaf area (SLA) in at least one exotic range region and five of those six species experienced reduced leaf herbivory. Increases in SLA were underpinned by increases in leaf area rather than reductions in leaf mass. No species showed differences in the direction of trait shifts from the native range between different exotic regions. This suggests that the driver of selection on these traits in the exotic range is consistent across regions and hence is most likely to be associated with factors linked with introduction to a novel environment, such as release from leaf herbivory, rather than with particular environmental conditions. Synthesis. These results provide evidence that introduction of a plant species into a

  9. Cabomba caroliniana A. Gray 1837: A new, alien and potentially invasive species in Serbia

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    Vukov Dragana

    2013-01-01

    Full Text Available During field studies of the vegetation in the canal network of the Hydro-System Danube-Tisa-Danube in Serbia, in 2008, 2011 and 2012, populations of Cabomba caroliniana A. Gray 1837 were recorded. Cabomba caroliniana was not previously recorded in the aquatic vegetation in Serbia. It is a popular aquarium plant native to South America (Brazil, Uruguay, Paraguay, and northeastern Argentina and, according to some authors, to southeastern United States. It was introduced into the rest of the USA, Canada, Australia, Asia (China, Malaysia, India, Japan, and in many regions of its new range it is considered an invasive and noxious aquatic weed. In Europe, it was found in the United Kingdom (introduced to England, Belgium, the Netherlands, and Hungary. Newly recorded populations in Serbia are restricted to the canals in Bačka. Populations are established only on two localities (Mali Stapar and Odžaci. [Projekat Ministarstva nauke Republike Srbije, br. III43002

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

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    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.

  11. Study on the Characteristics of Alien Invasive Plants of Wetland in Yunnan%云南湿地外来入侵植物特征研究

    Institute of Scientific and Technical Information of China (English)

    杨忠兴; 陶晶; 郑进烜

    2014-01-01

    通过对云南湿地外来入侵植物的实地调查,确定云南湿地外来入侵植物共有70种,隶属于24科54属;来源于5大洲,其中来源于美洲的植物种类最多,共47种,占67.1%;入侵途径以人为传入为主,占95.7%。按水分生态类型分,以中生植物为主;按生活型分,以草本为主;按繁殖方式分,以种子繁殖为主,但以无性繁殖为主的入侵物种扩散速度快,危害性大。外来入侵植物在云南省16个地州(市)129个县(区)的湿地均有分布,其中全省范围分布的有43种,占61.5%。%Based on the field survey of invasive plant of wetland in Yunnan province , it was found out that there were 70 alien invasive plants belonging to 54 genera, 24 families.They originated from 5 continents, and 47 spe-cies (67.1%) were from the American Continent .The invasive route were mainly introduced by human , account-ing for 95.7 %, and most of alien invasive plants were hygrophytes according to water ecotype , and were herbs according to life-form and were seed propagation according to reproduction type .The alien invasive plants by asexual reproduction expanded very fast which caused higher damages .The alien invasive plants were widely distributed in the wetland of 129 counties of 16 prefectures or municipalities in Yunnan , among of which 43 species ( 61.5 %) were distributed in the whole province .

  12. Invasion of Nostocales (cyanobacteria to subtropical and temperate freshwater lakes – Physiological, regional and global driving forces

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    Assaf eSukenik

    2012-03-01

    Full Text Available Similarly to the increased number of studies on invasive plants and animals in terrestrial and aquatic ecosystems, many reports were recently published on the invasion of Nostocales (cyanobacteria to freshwater environments worldwide. Invasion and proliferation of Nostocales in new habitats have the potential to significantly alter the structure of native community and to modify ecosystem functioning. But most importantly, they influence the water quality due to a variety of toxic compounds that some species produce. Therefore a special attention was given to the invasion and persistence of toxic cyanobacteria in many aquatic ecosystems. Here we summarize the currently published records on the invasion of two Nostocales genera, Cylindrospermopsis and Aphanizomenon, to lakes and water reservoirs in subtropical and temperate zones. These invading species possess traits thought to be common to many invasive organisms: high growth rate, high resource utilization efficiency and overall superior competitive abilities over native species when local conditions vary. Assuming that dispersion routes of cyanobacteria have not been changed much in recent decades, their recent establishment and proliferation in new habitats indicate changes in the environment under which they can exploit their physiological advantage over the native phytoplankton population. In many cases global warming was identified as the major driving force for the invasion of Nostocales. Due to this uncontrollable trend, invasive Nostocales species are expected to maintain their presence in new habitats and further expand to new environments. In other cases regional changes in nutrient loads and in biotic conditions were attributed to the invasion events

  13. Relative invasion risk for plankton across marine and freshwater systems: examining efficacy of proposed international ballast water discharge standards.

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    Oscar Casas-Monroy

    Full Text Available Understanding the implications of different management strategies is necessary to identify best conservation trajectories for ecosystems exposed to anthropogenic stressors. For example, science-based risk assessments at large scales are needed to understand efficacy of different vector management approaches aimed at preventing biological invasions associated with commercial shipping. We conducted a landscape-scale analysis to examine the relative invasion risk of ballast water discharges among different shipping pathways (e.g., Transoceanic, Coastal or Domestic, ecosystems (e.g., freshwater, brackish and marine, and timescales (annual and per discharge event under current and future management regimes. The arrival and survival potential of nonindigenous species (NIS was estimated based on directional shipping networks and their associated propagule pressure, environmental similarity between donor-recipient ecosystems (based on salinity and temperature, and effects of current and future management strategies (i.e., ballast water exchange and treatment to meet proposed international biological discharge standards. Our findings show that current requirements for ballast water exchange effectively reduce invasion risk to freshwater ecosystems but are less protective of marine ecosystems because of greater environmental mismatch between source (oceanic and recipient (freshwater ecoregions. Future requirements for ballast water treatment are expected to reduce risk of zooplankton NIS introductions across ecosystem types but are expected to be less effective in reducing risk of phytoplankton NIS. This large-scale risk assessment across heterogeneous ecosystems represents a major step towards understanding the likelihood of invasion in relation to shipping networks, the relative efficacy of different invasion management regimes and seizing opportunities to reduce the ecological and economic implications of biological invasions.

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

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    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.

  15. Profound effects of population density on fitness-related traits in an invasive freshwater snail.

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    Nicholas Zachar

    Full Text Available Population density can profoundly influence fitness-related traits and population dynamics, and density dependence plays a key role in many prominent ecological and evolutionary hypotheses. Here, we evaluated how individual-level changes in population density affect growth rate and embryo production early in reproductive maturity in two different asexual lineages of Potamopyrgus antipodarum, a New Zealand freshwater snail that is an important model system for ecotoxicology and the evolution of sexual reproduction as well as a potentially destructive worldwide invader. We showed that population density had a major influence on individual growth rate and early-maturity embryo production, effects that were often apparent even when comparing treatments that differed in population density by only one individual. While individual growth rate generally decreased as population density increased, we detected a hump-shaped relationship between embryo production and density, with females from intermediate-density treatments producing the most embryos and females from low- and high-density treatments producing the fewest embryos. The two lineages responded similarly to the treatments, indicating that these effects of population density might apply more broadly across P. antipodarum. These results indicate that there are profound and complex relationships between population density, growth rate, and early-maturity embryo production in at least two lineages of this important model system, with potential implications for the study of invasive populations, research on the maintenance of sex, and approaches used in ecotoxicology.

  16. Feeding kinematics of freshwater turtles: what advantage do invasive species possess?

    Science.gov (United States)

    Nishizawa, Hideaki; Tabata, Runa; Hori, Tomoya; Mitamura, Hiromich; Arai, Nobuaki

    2014-10-01

    The red-eared slider (Trachemys scripta) is an invasive turtle species that is displacing the populations of native freshwater turtles in many countries. However, the mechanism that makes red-eared sliders superior competitors has been less well studied. In this study, we compare the feeding kinematics of the red-eared slider with those of Reeves' pond turtle (Mauremys reevesii), a turtle native to East Asia, and offer an explanation as to why red-eared sliders are superior in food competition. Reeves' pond turtles sympatric to red-eared sliders have been reported to have a mainly durophagous diet in contrast to the preference for a soft diet in areas of allopatry to red-eared sliders, indicating the dietary shift resulted from food competition. Maximum neck extension and retraction speed are considered to be indicators of striking ability, but were not found to be superior in red-eared sliders. In fact, maximum neck extension speed was significantly higher in Reeves' pond turtles, though this advantage may be counteracted by the longer neck of Reeves' pond turtles, resulting in similar neck extension times. On the other hand, red-eared sliders had a significantly shorter gape cycle time and neck retraction time, indicating that they can complete feeding in a short time. Therefore, red-eared sliders are suggested to be superior in food competition not due to their striking ability, but due to exploiting preferable food in a shorter time.

  17. Historical freshwater fish ecology: a long-term view of distribution changes and biological invasions

    Directory of Open Access Journals (Sweden)

    Miguel Clavero

    2015-12-01

    Full Text Available Past processes and events may have an important influence on contemporaneous ecological patterns, including current human impacts on landscapes and organisms. In spite of that, most of the ecological knowledge has been built upon short-term studies, which very rarely exceed one decade. Ecology and Conservation Biology have an important lack of historical approaches, a deficiency that may become a hindrance for the management of natural systems. In this talk I will present examples of how historical information on the distribution of freshwater fish and other aquatic organisms can be used to address ecological questions. Most analyses are based on two important Spanish historical written sources: the Relaciones de Felipe II (16th century and the Madoz Dictionary (19th century. The examples considered include the European eel (Anguilla anguilla, the brown trout (Salmo trutta, the common carp (Cyprinus carpio and the white clawed crayfish (Austropotamobius italicus, among other species, as well as questions related to biological invasions, habitat loss and the impacts of global warming. The outputs of ecological research based on historical data often become useful tools for present-day biodiversity conservation planning and actions.

  18. Potential distribution of the invasive freshwater dinoflagellate Ceratium furcoides (Levander) Langhans (Dinophyta) in South America.

    Science.gov (United States)

    Meichtry de Zaburlín, Norma; Vogler, Roberto E; Molina, María J; Llano, Víctor M

    2016-04-01

    Dinoflagellates of the genus Ceratium are predominantly found in marine environments, with a few species in inland waters. Over the last decades, the freshwater species Ceratium hirundinella and Ceratium furcoides have colonized and invaded several South American basins. The purpose of this study was to create a distribution model for the invasive dinoflagellate C. furcoides in South America in order to further investigate the basins at potential risk, as well as the environmental conditions that influence its expansion. This species is known to develop blooms due to its mobility, resistance to sedimentation, and optimized use of resources. Although nontoxic, blooms of the species cause many problems to both the natural ecosystems and water users. Potential distribution was predicted by using a maximum entropy algorithm (MaxEnt). Model was run with 101 occurrences obtained from the scientific literature, and climatic, hydrological and topographic variables. The developed model had a very good performance for the study area. The most susceptible areas identified were mainly concentrated in the basins between southeastern Brazil and northeastern Argentina. Besides already affected regions, new potentially suitable areas were identified in temperate regions of South America. The information generated here will be useful for authorities responsible for water and watershed management to monitor the spread of this species and address problems related to its establishment in new environments.

  19. 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

  20. 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

  1. Study on Present Situation of Invasive Alien Species in Xinjiang%新疆外来入侵种现状研究

    Institute of Scientific and Technical Information of China (English)

    陈丽

    2012-01-01

    通过对我国新疆9种已呈现出较大危害的外来入侵种的分布范围、生境类型、种群建立状况、起源、首次发现或引入的地点及时间、来源、引入路径、入侵途径、经济和生态影响等内容进行了研究,并深入分析了目前外来入侵种管理等方面存在的问题,提出了外来入侵物种预防、控制和管理措施。%This paper researched distribution,habitat types,populations to establish the status,origin,the place and time found or introduced for the first time,introduction path,invasion pathways,economic and ecological impact and other aspects of nine kinds of invasive alien species which have shown a greater hazard in Xinjiang,analyzed the problems of alien invasive species management,and put forwards the prevention,control and management measures.

  2. 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

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

    CSIR Research Space (South Africa)

    Ntshotsho, P

    2015-10-01

    Full Text Available Ntshotsho and her colleagues sought to verify and characterise success in government’s efforts to restore degraded ecosystems through invasive alien plant management. Invasive alien plants pose a significant threat to South Africa’s biodiversity...

  4. Muddied waters: suspended sediment impacts on gill structure and aerobic scope in an endangered native and an invasive freshwater crayfish

    DEFF Research Database (Denmark)

    Rosewarne, P.J.; Svendsen, Jon Christian; Mortimer, R.J.G.

    2014-01-01

    Suspended sediment (SS) loadings in freshwater habitats have increased over the past century and SS is now a significant environmental stressor. Greater tolerance to environmental stressors has been proposed as a factor in the success of aquatic invasive species. Further, parasites may interact...... with environmental stressors to increase host susceptibility to loss of fitness and mortality. We compared the effects of SS exposure on the gill structure and aerobic scope of the endangered white-clawed crayfish (Austropotamobius pallipes), and the invasive signal crayfish (Pacifastacus leniusculus), and assessed...... impacts in relation to parasite burden. SS caused gill fouling and reduction in aerobic scope in both species, though A. pallipes was more susceptible than invasive P. leniusculus. The parasite Branchiobdella astaci, a crayfish worm that infests the gills, interacted with the sediment to affect gill...

  5. 外来寄生虫入侵及其对土著宿主的影响%Invasion of Alien Parasites and Its Impacts on Native Hosts

    Institute of Scientific and Technical Information of China (English)

    孔萌萌; 李文祥

    2016-01-01

    Biological invasion is a major threat to native species and biodiversity.Invasive parasites are introduced with the alien hosts and also considered as invasive species.In this paper,parasites invading processes including species introduction,population establishment and host switching were summarized by analyzing invasion cases of exotic parasites.Generally,the invasive parasites were more virulent in native hosts than in the co-introduced alien host.Some invasive parasites resulted in direct or indirect death of native hosts and some species decreased repro-duction ability of native hosts populations,consequently decreasing community diversity of native hosts.We also discussed the control and management of parasite invasion according to the invasive process of parasites:firstly,to avoid translocation of parasites with the introduction of hosts by taking early warning measures,including transporta-tion management and introduced species management ;then,to prevent establishment of parasite population by e-radicating reservoir hosts,controlling vectors,vaccinating susceptible hosts and implementing habitat management;finally,to take mitigation measures such as managing native host and vector population,cutting off corridors to limit further invasive spread.%生物入侵严重威胁着土著物种和生物多样性,外来物种带来的寄生虫入侵问题也应该引起相应的重视。结合外来寄生虫的入侵案例,阐述了寄生虫的引入、种群建立和宿主转移等入侵过程。通常寄生虫入侵后,致病力会变得更大,有些会直接引起土著宿主的死亡,有些间接引起宿主死亡,有的则引起繁殖力下降,从而降低土著宿主的群落多样性,讨论了寄生虫入侵的管理和控制。

  6. INVASIVENESS, CLONALITY AND HABITAT OF ALIEN INVASIVE PLANT IN VIRGINIA OF AMERICA%美国弗吉尼亚州入侵植物入侵性、克隆性和分布生境研究

    Institute of Scientific and Technical Information of China (English)

    肖赟君; 王宁; 周兵; 闫小红

    2014-01-01

    The invasiveness of alien invasive clonal plants might be affected by their clonality. The 109 alien invasive plants in Virginia of America were analyzed. The results showed that there are 59 invasive clonal plants (54.1%), whose mainly reproductive types were stolon and tiller. The percentage of the strongest invasiveness plants, the stronger invasiveness plants, the weaker invasiveness plants in all invasive plants are 30.3%, 44%and 25.7%, with clonal plants accounting for 48.5%, 56.3%, 57.1%respectively. Most of invasive plants were annual or biennial herbs, perennial herbs, shrub and vine, which belonged to Gramineae, Leguminosae and Compositae mainly. The majority of invasive plants distributed in adequate lighting and wet habitats. Data mentioned above indicated that clonality of the invasive plants in Virginia may be contributed significantly to their invasiveness, and most of invasive plants had strong ability of occupying habitat.%为了探讨入侵克隆植物入侵性与其克隆性之间的相关性,对美国弗吉尼亚州109种外来入侵植物进行了相关研究,结果表明:克隆植物有59种,占入侵植物总数的54.1%,且多数可通过根茎、分蘖等方式进行繁殖。入侵性最强的物种、较强的物种、较弱的物种分别占入侵植物总数的30.3%、44%、25.7%,其中克隆植物所占比例依次为:48.5%、56.3%和57.1%。上述入侵植物多为1~2年生草本、多年生草本、灌木和藤本类入侵植物,禾本科、豆科和菊科等科植物占据多数,多生长分布在光照充足、水分适宜的生境。上述结果表明,弗吉尼亚州入侵植物的克隆性可能促进了其入侵性,多数入侵植物具有较强的生境占据能力。

  7. 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 Biological invasions are a major driver of ecological and social change globally. The negative effects of these invasions have led to the initiation of programs to manage these invasions across the world. Management aims to reduce impacts...

  8. 外来入侵豚草综合治理研究进展%Cai-taiAdvances in Integrated Control of Invasive Alien Plant Ambrosia artemisiifolia

    Institute of Scientific and Technical Information of China (English)

    王娟; 邓旭; 谭济才

    2011-01-01

    Ambrosia is a kind of invasive alien weed, whose invasion not only threatens native biodiversity and ecosystems, but also causes considerable economic loss. In order to control the damage of Ambrosia effectively, on the basis of introducing mechanical, chemical and biological control methods, the insufficiencies of them were clarified and an integrated control measure was proposed.%豚草属(Ambrosia)是一种外来恶性杂草,它的入侵不仅威胁了当地生物多样性和生态系统,还导致巨大的经济损失.为有效控制其危害,在介绍豚草人工、化学、生物控制方法的基础上,针对各种方法不足之处.提出了综合控制措施.

  9. 外来物种入侵的刑事控制模式%On Criminal Control Pattern of Invasive Alien Species

    Institute of Scientific and Technical Information of China (English)

    王振

    2013-01-01

    Invasive alien species has been becoming a risking factor that is very harmful to the ecological security besides lives and health of human being, so it is necessary to regulating the invasive alien species in criminal law.Analyzing the protecting ways of the legal interests of environment in criminal law, we should take the potential damage offense and the indeed damage offense together into account in criminal legislation.At the same time, it is right rout to introducing the epidemiology causality, based on probability theory and the statistical science to settling the mazy problem of the causality of criminal law about eco-crimes.%物种入侵正日益成为危害人类生命健康、生态环境安全的又一风险因素;对物种入侵行为的刑法规制的犯罪构成模式设计是危险犯与实害犯并用;建立在统计科学概率论基础上的疫学因果关系是破解生态犯罪刑法因果关系的合理选择.

  10. Comparison of remote sensing data sources and techniques for identifying and classifying alien invasive vegetation in riparian zones

    CSIR Research Space (South Africa)

    Rowlinson, LC

    1999-10-01

    Full Text Available of large amounts of water from riparian zones, is one of the methods of maximising water supply in South Africa. Remote sensing is a cost- and time-effective technique for identifying alien vegetation in riparian zones and remote sensing data can...

  11. Alien animals in South Africa – composition, introduction history, origins and distribution patterns

    Directory of Open Access Journals (Sweden)

    Mike D. Picker

    2017-03-01

    Full Text Available Background: There is no comprehensive inventory and analysis of the composition, distribution, origin and rate of introduction of the alien fauna of South Africa. Objectives: To provide such an analysis to facilitate effective ecological management, and compile a comprehensive inventory of introduced animal species across major habitats. Methods: All available databases and references were used to compile the inventory, forming the basis of subsequent analyses. A graduated map was produced to identify concentrations of alien species.Results: Of the 571 alien animal species analysed, insects comprised the largest component (53%, 300 species, followed by molluscs (9%, 51 species, annelids (8%, 48 species, arachnids (7%, 41 species, vertebrates (7%, 41 species and crustaceans (6%, 36 species. Vertebrate introductions (88% were largely intentional, whereas 84% of invertebrate introductions were unintentional. Conclusions: Almost all marine and most terrestrial alien species were accidentally introduced, whereas freshwater introductions were almost entirely intentional. Some 13% had not spread significantly, 16% had spread significantly and 71% had become fully invasive. Vertebrate introductions virtually ceased after the 1950s, but rate of introduction of invertebrates remained linear. The overall rate of species accumulation was fairly low until 1880, but accelerated sharply thereafter. Most terrestrial alien species originated from Europe (28.6% and Asia (25.0% and the lowest proportion (6.1% from Africa. Freshwater introductions largely originated from the Americas, with few from Africa. The most invaded areas were around Cape Town, (up to 162 introduced species/half-degree grid cell, followed by Gauteng and Durban

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

    Directory of Open Access Journals (Sweden)

    Richard M. Cowling

    2011-09-01

    Full Text Available The recently established Garden Route National Park (GRNP along the Cape south coast of South Africa occurs in a landscape where indigenous forests, fire-prone fynbos shrublands and fire-sensitive plantations of alien invasive trees are interspersed. We used the area as a case study in the challenges facing conservation managers in the achievement of biodiversity goals in a fire-prone environment. We explored the context within which fire management was practised during the past century by interviewing former catchment managers and reviewing forestry and catchment management policies. Mountain fynbos adjacent to plantations was subjected to burning regimes aimed at the protection of commercial timber resources rather than the preservation of fynbos biodiversity. Prescribed burning of fynbos adjacent to the plantations was typically done in multiple belt systems at rotations of about 4–8 years during spring, summer and autumn, to avoid the winter berg wind season. Such short-rotation and low-intensity fires favour resprouting graminoids over slow-maturing reseeders, and likely account for the compositional impoverishment observed in fynbos near plantations. Current and future challenges faced by the GRNP include (1 balancing conflicting fire management requirements for plantation safety against fynbos conservation; (2 the continual invasion of fynbos by fire-propagated alien pines sourced from plantations; (3 inadequate resources to redress the ‘invasion debt’ caused by the socio-economic legacy and past management neglect; and (4 fragmentation of land use between conservation and forestry threatening the sustainability of the region at large. We provide recommendations for management actions and research priorities to address these challenges.

  13. 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

  14. 广西北部湾经济区外来入侵植物%The Alien Invasive Phmts in Guangxi Beibu Gulf Economic Zone

    Institute of Scientific and Technical Information of China (English)

    林建勇; 温远光; 韦洁

    2011-01-01

    根据野外调查和相关资料整理,初步探讨了广西北部湾经济区外来入侵植物的种类组成、原产地、引入途径、生境类型、分布情况和危害程度。结果表明:该区现有外来入侵植物31科69属87种,种数最多的有菊科(Compositae)和禾本科(Gramineae),其中来源于美洲的种类最多,有67种,占总种数77.9%。危害状况严重的有15种,危害中等的有30种,危害较轻的有41种。保护本地生态系统、建立外来入侵物种监测机制和风险评价体系将是防范外来入侵植物的有效途径。%According to field investigation and related materials, the species, place of origin, introducing approaches, habitats, distribution and harmfulness of alien invasive plants in Guangxi Beibu Gulf Economic Zone were discussed. The results showed that 87 species of alien invasive plants belonging to 69 genera and 31 families were identified, most of Compositae and Gramineae. Constitutional analysis of the original locality revealed that 67 species were from Tropical America which took up 77.9 % of the total species. And 15 species were ,evaluated to be at the high degree of threat to the local biodiversity, 30 at the medium, and 41 at the low. The most effective strategies were to protect native ecosystem and to establish monitor mechanism and risk assessment system of alien invasive plants.

  15. A Legislative Research on Prevention and Control of Alien Species Invasion%我国外来物种入侵防治立法研究

    Institute of Scientific and Technical Information of China (English)

    鲁继平

    2015-01-01

    To reverse the grave situation of alien species invasion in China, we should make a legislative research on prevention and control of the invasion. It will help transform some effective rules and measures into legal norms, thus promoting the administrative work according to law in this respect. One of the most effective measures to control invasion of alien species is to formulate Law on Prevention and Control of Alien Species Invasion (hereafter referred to as the Law). It is not only an important initiative to implement the relevant documents issued by the Party Central Committee and the State Council but also a necessary requirement of sustainable development. Chinese government is now paying high attention to the prevention and control of alien species invasion. In view of our plenty practices and other countries ' experiences, we should as soon as possible enact the Law on the basis of the existing law and regulations. The author suggest the Law be composed of General Provisions, Foreword, Survey, Prevention & Control, Supervision & Administration, Legal Liabilities and Supplementary Provisions. In the Legal Liabilities not only administrative and criminal liabilities should be stipulated, feasible civil liabilities should also be clearly defined.%开展外来物种入侵防治立法不仅有利于扭转我国外来物种入侵防治的严峻形势, 而且也有利于将许多行之有效的制度和措施上升为法律规范,从而有力地促进我国外来物种入侵防治工作的依法开展和依法行政. 制定外来物种入侵防治法是落实党中央、国务院有关文件要求的重要举措,是实施可持续发展战略的必然要求,是防治外来物种入侵最有效的手段之一. 目前,我国对外来物种入侵防治工作高度重视,已积累了丰富的实践经验,同时又有可供参考、借鉴的国外立法经验. 因此,应在充分考虑现行法律规范的基础上,尽快制定出台我国外来物种入侵防治法,

  16. 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)

    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. PMID:27992516

  17. 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.

  18. 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.

  19. 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.

  20. Discussion On the Civil Liability of Alien Species Invasion%外来物种入侵的民事责任构成之探讨

    Institute of Scientific and Technical Information of China (English)

    童光法; 佟占军

    2012-01-01

    经过许可的有意引种行为和无意引种行为,引种人不需要承担民事责任;此时应当设立国家外来物种入侵防治基金.在未经许可的有意引种行为,适用一般侵权行为的过错归责原则,即适用《侵权责任法》第6条而不适用第65条的规定;基于已建立的国家引种许可证制度和相应的数据库,来认定该未经许可的引种行为具有违法性;在因果关系证明上,原告方只需就责任成立的因果关系进行证明.%Under the authorization of introduction of alien species or any unintentional introduction, a person shouldn't bear civil liability for the damages when the action leads to invasion. Under this circumstance, the state should advocate establishment of environmental fund for preventing and controlling alien species invasion. Without any permission, a person should bear fault liability according to the article 6 (not article 65) of Tort Liability Act. Based on the licensing system, list system and the corresponding database, we hold the wrongfulness of the unauthorized actions. The plaintiff shouldn't prove the legal cause but the cause in fact.

  1. 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. PMID:26010250

  2. Composition and distribution of invasive alien plants in Suzhou area%苏州地区外来入侵植物组成及分布

    Institute of Scientific and Technical Information of China (English)

    林敏; 郝建华; 陈国奇

    2012-01-01

    为了解苏州外来入侵植物的种类组成及分布概况,对苏州地区6个县市(包括常熟、昆山、苏州、太仓、吴江和张家港)26个样点内不同生境中的外来入侵植物进行了调查分析.调查结果显示:每个样点有外来人侵植物7~25种,平均每个样点有17.9种.在26个样点中观察到外来入侵植物57种,隶属于19科45属;其中菊科(Compositae)种类最多(23种),占总种数的40.4%;豆科(Leguminosae)、玄参科(Scrophulariaceae)、禾本科(Poaceae)、伞形科(Apiaceae)、苋科(Amaranthaceae)和旋花科(Convolvulaceae)种类也较多.原产于北美洲和欧洲的种类分别有20和12种,分别占总种数的35.1%和21.0%;还有17种原产于美洲的其他区域,少数种类原产于非洲、西亚和地中海地区.在57种外来入侵植物中,草本植物有55种,非多年生植物有44种,分别占总种数的96.5%和77.2%.有18种的频度超过50%,其中加拿大一枝黄花(Solidago canadensis L.)和一年蓬[Erigeron annuus (L.) Pers.]的频度最高,分别达到96.15%和92.31%,且多度等级均属于极多级(Soc);空心莲子草[ Ahernanthera philoxeroides( Mart.) Griseb.]和白车轴草(Trifolium repens L.)的频度也均在80%以上,且多度等级也属于极多级(Soc).调查结果表明:苏州地区外来植物入侵现象比较严重.%In order to understand species composition and distribution of invasive alien plants in Suzhou, invasive alien plants in different habitats of 26 sample plots in six counties or cities (including Changshu, Kunshan, Suzhou, Taicang, Wujiang and Zhangjiagang) of Suzhou area were investigated and analyzed. The investigation results show that there are 7-25 species of invasive alien plants in these plots with the average of 17. 9 species per plot. There are 57 species of invasive alien plants observed in 26 sample plots, belonging to 45 genera in 19 families. In which, species number in Compositae (23 species) is the most

  3. Optimising invasive fish management in the context of invasive species legislation in South Africa

    OpenAIRE

    Woodford, Darragh J.; Phillip Ivey; Jordaan, Martine S.; Peter K. Kimberg; Tsungai Zengeya; Olaf L.F. Weyl

    2017-01-01

    Background: South Africa hosts a large number of non-native freshwater fishes that were introduced for various industries. Many of these species are now listed under the National Environmental Management: Biodiversity Act (NEM:BA) Alien and Invasive Species (A&IS) lists and regulations, though the practical options available to conservation agencies to effectively manage these fishes vary greatly among species and regions. Objectives & methods: We assessed the history and status of na...

  4. Characterization of the salt stress vulnerability of three invasive freshwater plant species using a metabolic profiling approach.

    Science.gov (United States)

    Thouvenot, Lise; Deleu, Carole; Berardocco, Solenne; Haury, Jacques; Thiébaut, Gabrielle

    2015-03-01

    The effects of salt stress on freshwater plants has been little studied up to now, despite the fact that they are expected to present different levels of salt sensitivity or salt resistance depending on the species. The aim of this work was to assess the effect of NaCl at two concentrations on three invasive freshwater species, Elodea canadensis, Myriophyllum aquaticum and Ludwigia grandiflora, by examining morphological and physiological parameters and using metabolic profiling. The growth rate (biomass and stem length) was reduced for all species, whatever the salt treatment, but the response to salt differed between the three species, depending on the NaCl concentration. For E. canadensis, the physiological traits and metabolic profiles were only slightly modified in response to salt, whereas M. aquaticum and L. grandiflora showed great changes. In both of these species, root number, photosynthetic pigment content, amino acids and carbohydrate metabolism were affected by the salt treatments. Moreover, we are the first to report the salt-induced accumulation of compatible solutes in both species. Indeed, in response to NaCl, L. grandiflora mainly accumulated sucrose. The response of M. aquaticum was more complex, because it accumulated not only sucrose and myo-inositol whatever the level of salt stress, but also amino acids such as proline and GABA, but only at high NaCl concentrations. These responses are the metabolic responses typically found in terrestrial plants.

  5. 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 ...

  6. Survivorship and feeding preferences among size classes of outplanted sea urchins, Tripneustes gratilla, and possible use as biocontrol for invasive alien algae.

    Science.gov (United States)

    Westbrook, Charley E; Ringang, Rory R; Cantero, Sean Michael A; Toonen, Robert J

    2015-01-01

    We investigate the survivorship, growth and diet preferences of hatchery-raised juvenile urchins, Tripneustes gratilla, to evaluate the efficacy of their use as biocontrol agents in the efforts to reduce alien invasive algae. In flow-through tanks, we measured urchin growth rates, feeding rates and feeding preferences among diets of the most common invasive algae found in Kāne'ohe Bay, Hawai'i: Acanthophora spicifera, Gracilaria salicornia, Eucheuma denticulatum and Kappaphycus clade B. Post-transport survivorship of outplanted urchins was measured in paired open and closed cages in three different reef environments (lagoon, reef flat and reef slope) for a month. Survivorship in closed cages was highest on the reef flat (∼75%), and intermediate in the lagoon and reef slope (∼50%). In contrast, open cages showed similar survivorship on the reef flat and in the lagoon, but only 20% of juvenile urchins survived in open cages placed on the reef slope. Urchins grew significantly faster on diets of G. salicornia (1.58 mm/week ± 0.14 SE) and Kappaphycus clade B (1.69 ± 0.14 mm/wk) than on E. denticulatum (0.97 ± 0.14 mm/wk), with intermediate growth when fed on A. spicifera (1.23 ± 0.11 mm/wk). Interestingly, urchins display size-specific feeding preferences. In non-choice feeding trials, small urchins (17.5-22.5 mm test diameter) consumed G. salicornia fastest (6.08 g/day ± 0.19 SE), with A. spicifera (4.25 ± 0.02 g/day) and Kappaphycus clade B (3.83 ± 0.02 g/day) intermediate, and E. denticulatum was clearly the least consumed (2.32 ± 0.37 g/day). Medium-sized (29.8-43.8 mm) urchins likewise preferentially consumed G. salicornia (12.60 ± 0.08 g/day), with less clear differences among the other species in which E. denticulatum was still consumed least (9.35 ± 0.90 g/day). In contrast, large urchins (45.0-65.0 mm) showed no significant preferences among the different algae species at all (12.43-15.24 g/day). Overall consumption rates in non-choice trials

  7. Survivorship and feeding preferences among size classes of outplanted sea urchins, Tripneustes gratilla, and possible use as biocontrol for invasive alien algae

    Directory of Open Access Journals (Sweden)

    Charley E. Westbrook

    2015-09-01

    Full Text Available We investigate the survivorship, growth and diet preferences of hatchery-raised juvenile urchins, Tripneustes gratilla, to evaluate the efficacy of their use as biocontrol agents in the efforts to reduce alien invasive algae. In flow-through tanks, we measured urchin growth rates, feeding rates and feeding preferences among diets of the most common invasive algae found in Kāneʻohe Bay, Hawaiʻi: Acanthophora spicifera, Gracilaria salicornia, Eucheuma denticulatum and Kappaphycus clade B. Post-transport survivorship of outplanted urchins was measured in paired open and closed cages in three different reef environments (lagoon, reef flat and reef slope for a month. Survivorship in closed cages was highest on the reef flat (∼75%, and intermediate in the lagoon and reef slope (∼50%. In contrast, open cages showed similar survivorship on the reef flat and in the lagoon, but only 20% of juvenile urchins survived in open cages placed on the reef slope. Urchins grew significantly faster on diets of G. salicornia (1.58 mm/week ± 0.14 SE and Kappaphycus clade B (1.69 ± 0.14 mm/wk than on E. denticulatum (0.97 ± 0.14 mm/wk, with intermediate growth when fed on A. spicifera (1.23 ± 0.11 mm/wk. Interestingly, urchins display size-specific feeding preferences. In non-choice feeding trials, small urchins (17.5–22.5 mm test diameter consumed G. salicornia fastest (6.08 g/day ± 0.19 SE, with A. spicifera (4.25 ± 0.02 g/day and Kappaphycus clade B (3.83 ± 0.02 g/day intermediate, and E. denticulatum was clearly the least consumed (2.32 ± 0.37 g/day. Medium-sized (29.8–43.8 mm urchins likewise preferentially consumed G. salicornia (12.60 ± 0.08 g/day, with less clear differences among the other species in which E. denticulatum was still consumed least (9.35 ± 0.90 g/day. In contrast, large urchins (45.0–65.0 mm showed no significant preferences among the different algae species at all (12.43–15.24 g/day. Overall consumption rates in non

  8. Survivorship and feeding preferences among size classes of outplanted sea urchins, Tripneustes gratilla, and possible use as biocontrol for invasive alien algae

    Science.gov (United States)

    Ringang, Rory R.; Cantero, Sean Michael A.; Toonen, Robert J.

    2015-01-01

    We investigate the survivorship, growth and diet preferences of hatchery-raised juvenile urchins, Tripneustes gratilla, to evaluate the efficacy of their use as biocontrol agents in the efforts to reduce alien invasive algae. In flow-through tanks, we measured urchin growth rates, feeding rates and feeding preferences among diets of the most common invasive algae found in Kāneʻohe Bay, Hawaiʻi: Acanthophora spicifera, Gracilaria salicornia, Eucheuma denticulatum and Kappaphycus clade B. Post-transport survivorship of outplanted urchins was measured in paired open and closed cages in three different reef environments (lagoon, reef flat and reef slope) for a month. Survivorship in closed cages was highest on the reef flat (∼75%), and intermediate in the lagoon and reef slope (∼50%). In contrast, open cages showed similar survivorship on the reef flat and in the lagoon, but only 20% of juvenile urchins survived in open cages placed on the reef slope. Urchins grew significantly faster on diets of G. salicornia (1.58 mm/week ± 0.14 SE) and Kappaphycus clade B (1.69 ± 0.14 mm/wk) than on E. denticulatum (0.97 ± 0.14 mm/wk), with intermediate growth when fed on A. spicifera (1.23 ± 0.11 mm/wk). Interestingly, urchins display size-specific feeding preferences. In non-choice feeding trials, small urchins (17.5–22.5 mm test diameter) consumed G. salicornia fastest (6.08 g/day ± 0.19 SE), with A. spicifera (4.25 ± 0.02 g/day) and Kappaphycus clade B (3.83 ± 0.02 g/day) intermediate, and E. denticulatum was clearly the least consumed (2.32 ± 0.37 g/day). Medium-sized (29.8–43.8 mm) urchins likewise preferentially consumed G. salicornia (12.60 ± 0.08 g/day), with less clear differences among the other species in which E. denticulatum was still consumed least (9.35 ± 0.90 g/day). In contrast, large urchins (45.0–65.0 mm) showed no significant preferences among the different algae species at all (12.43–15.24 g/day). Overall consumption rates in non

  9. Competitive replacement of the native Vitis and Hedera taxa by invasive aliens: morphological, cytological and molecular evidences

    Directory of Open Access Journals (Sweden)

    Maria HOHN

    2012-10-01

    Full Text Available We describe here case studies of two woody climber species native to the broadleaf forests of the Carpathian basin. Wild grape (Vitis sylvestris C.C.Gmel., considered to be one of the ancestors of the domesticated grapevine (Vitis vinifera L. became a highly threatened species since the introduction of the American grape species as rootstocks for grapevine. Among these, especially, Riparian grape (Vitis riparia Minchx. escaped from the wine yards and by invading the natural habitats replaced the autochthonous wild grape. In consequence of the competitive exclusion Vitis sylvestris suffered a strong withdrawal along its native habitats. 20 morphological traits, including leaf shape and trichome structure were studied to tackle evidence of the introgressive hybridization among the alien and native taxa. Most of the studied Hungarian habitats were already dominated by hybrid specimens of Vitis taxa. Molecular analysis based on 8 nuclear microsatellites markers supported the morphological results. 

  10. 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

  11. 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

    2009-07-27

    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.

  12. 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.

    2016-01-01

    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

  13. Can ozone be used to control the spread of freshwater Aquatic Invasive Species?

    Science.gov (United States)

    Buley, Riley P.; Hasler, Caleb T.; Tix, John A.; Suski, Cory D.; Hubert, Terrance D.

    2017-01-01

    The introduction of aquatic invasive species to non-native habitats can cause negative ecological effects and also billions of dollars in economic damage to governments and private industries. Once aquatic invasive species are introduced, eradication may be difficult without adversely affecting native species and habitats, urging resource managers to find preventative methods to protect non-invaded areas. The use of ozone (O3) as a non-physical barrier has shown promise as it is lethal to a wide range of aquatic taxa, requires a short contact time, and is relatively environmentally safe in aquatic systems when compared to other chemicals. However, before O3 can be considered as an approach to prevent the spread of aquatic invasive species, its effects on non-target organisms and already established aquatic invasive species must be fully evaluated. A review of the current literature was conducted to summarize data regarding the effects of O3 on aquatic taxa including fish, macroinvertebrates, zooplankton, phytoplankton, microbes, and pathogens. In addition, we assessed the practicality of ozone applications to control the movement of aquatic invasive species, and identified data gaps concerning the use of O3 as a non-physical barrier in field applications.

  14. Effects of Invasive-Plant Management on Nitrogen-Removal Services in Freshwater Tidal Marshes.

    Science.gov (United States)

    Alldred, Mary; Baines, Stephen B; Findlay, Stuart

    2016-01-01

    Establishing relationships between biodiversity and ecosystem function is an ongoing endeavor in contemporary ecosystem and community ecology, with important practical implications for conservation and the maintenance of ecosystem services. Removal of invasive plant species to conserve native diversity is a common management objective in many ecosystems, including wetlands. However, substantial changes in plant community composition have the potential to alter sediment characteristics and ecosystem services, including permanent removal of nitrogen from these systems via microbial denitrification. A balanced assessment of costs associated with keeping and removing invasive plants is needed to manage simultaneously for biodiversity and pollution targets. We monitored small-scale removals of Phragmites australis over four years to determine their effects on potential denitrification rates relative to three untreated Phragmites sites and adjacent sites dominated by native Typha angustifolia. Sediment ammonium increased following the removal of vegetation from treated sites, likely as a result of decreases in both plant uptake and nitrification. Denitrification potentials were lower in removal sites relative to untreated Phragmites sites, a pattern that persisted at least two years following removal as native plant species began to re-colonize treated sites. These results suggest the potential for a trade-off between invasive-plant management and nitrogen-removal services. A balanced assessment of costs associated with keeping versus removing invasive plants is needed to adequately manage simultaneously for biodiversity and pollution targets.

  15. Effects of Invasive-Plant Management on Nitrogen-Removal Services in Freshwater Tidal Marshes.

    Directory of Open Access Journals (Sweden)

    Mary Alldred

    Full Text Available Establishing relationships between biodiversity and ecosystem function is an ongoing endeavor in contemporary ecosystem and community ecology, with important practical implications for conservation and the maintenance of ecosystem services. Removal of invasive plant species to conserve native diversity is a common management objective in many ecosystems, including wetlands. However, substantial changes in plant community composition have the potential to alter sediment characteristics and ecosystem services, including permanent removal of nitrogen from these systems via microbial denitrification. A balanced assessment of costs associated with keeping and removing invasive plants is needed to manage simultaneously for biodiversity and pollution targets. We monitored small-scale removals of Phragmites australis over four years to determine their effects on potential denitrification rates relative to three untreated Phragmites sites and adjacent sites dominated by native Typha angustifolia. Sediment ammonium increased following the removal of vegetation from treated sites, likely as a result of decreases in both plant uptake and nitrification. Denitrification potentials were lower in removal sites relative to untreated Phragmites sites, a pattern that persisted at least two years following removal as native plant species began to re-colonize treated sites. These results suggest the potential for a trade-off between invasive-plant management and nitrogen-removal services. A balanced assessment of costs associated with keeping versus removing invasive plants is needed to adequately manage simultaneously for biodiversity and pollution targets.

  16. Invasion risks posed by ornamental freshwater fish trade to southeastern Brazilian rivers

    Directory of Open Access Journals (Sweden)

    Andre Lincoln Barroso de Magalhaes

    Full Text Available A model was developed to assess the risk of invasion of ornamental non-native fishes to six rivers in the state of Minas Gerais, southeastern Brazil, with focus on species popularity. Thirty-nine aquarium shops, in six cities, were visited monthly from January to December 2007. In each city, fish species were identified, and their biology and invasion history information was obtained from the literature. We calculated the annual frequency of occurrence and average number of specimens monthly available in stores. Quarterly water temperature and dissolved oxygen data from 1997 to 2007 were obtained for the Velhas, Muriaé, Uberabinha, Sapucaí-Mirim, Doce and Todos os Santos Rivers from public databases. The invasion risk of each species was assessed through a model comprising nine parameters grouped in four variables: (i Invasiveness (thermal and dissolved oxygen ranges, diet, parental care or fecundity, (ii History of invasions (establishment, (iii Propagule pressure (commercial success, comprising annual frequency of occurrence and number of specimens available monthly at stores, and (iv Invasibility (water temperature and dissolved oxygen in the target river compatible with the species ranges. Of the 345 ornamental fish species for sale, 332 are non-native to either Minas Gerais (n = 151 or Brazil (n = 194. Based on the proposed cutting values, in particular the compatibility between species and recipient thermal ranges, five ornamental non-native species (Cyprinus rubrofuscus, Carassius auratus, Xiphophorus hellerii, Poecilia reticulata, and P. latipinna can potentially invade the Velhas and Muriaé Rivers, four species (Cyprinus rubrofuscus, Carassius auratus, X. helleri, and P. reticulata the Uberabinha River, four species (Cyprinus rubrofuscus, Carassius auratus, X. maculatus, and P. reticulata the Sapucaí-Mirim River, three species (Carassius auratus, X. hellerii, and P. reticulata the Doce River, and three species (Cyprinus rubrofuscus

  17. Genomic signature and cluster analysis of genetic diversity of alien invasive species%外来入侵物种的基因签名及其遗传多样性聚类分析

    Institute of Scientific and Technical Information of China (English)

    谈承杰; 朱平

    2013-01-01

      密码子的使用频率分布能够反映一定的生物特性,因而可作为一种基因签名。本文使用CGR方法来研究外来入侵物种不同组织序列的基因签名及遗传多样性聚类分析,首先得出了刺花莲子草(Alternanthera pungens),紫茎泽兰(Ageratina adenophora),水葫芦(Eichhornia crassipes),微甘菊(Mikania micrantha),土荆芥(Chenopodium ambrosioides),一枝黄花(Solidago canadensis)等6种外来入侵植物的31条序列核苷酸字串长k=1到k=6的情况,并选取k=3,即基因序列的密码子,作为生物特性的一个重要表达。并且构造序列间的CGR欧式距离,进而对外来入侵植物序列遗传多样性进行了聚类分析。通过对所获得的6种外来入侵植物的31条序列的基因签名,得出如下结果:CGR是一种简便且计算量小的方法,且基于CGR方法的基因签名,具有典型的生物特性;入侵植物的基因序列在密码子的使用上是非均衡的,且物种亲缘关系近的,则基因签名相似越高;而且基因签名也揭示出了密码子的第三位碱基偏好使用碱基T的现象,与一般物种密码子第三位碱基偏好G/C情况有强烈反差。此外,从获得的6个物种的31条序列聚类谱系图可以直观看出,入侵植物间存在着一定的亲缘关系,遗传多样性较丰富。由于我们所建立的基于CGR方法的基因签名,不仅能够反映植物特性和进化关系,而且能揭示序列中密码子和碱基的偏好使用情况,因而该方法有利于对外来入侵物种的遗传多样性分析、风险评估及预防控制等提供科学依据。%Alien invasive species had been a global eco-environmental problem, resulting in huge economic loss. The distribution of codon usage could reflect some biological characteristics, therefore it could be a genomic signature. The paper proposed a genomic signature-based approach, using CGR with word length of k=3, which

  18. 梅州城市湿地外来入侵植物现状及防治对策%Alien Invasive Plants and Their Control in Urban Wetlands of Meizhou

    Institute of Scientific and Technical Information of China (English)

    曾兰华; 杨礼文; 俞万源; 李海山; 欧先交

    2013-01-01

    通过实地调查和文献检索,对梅州城市湿地外来入侵植物的组成、生活型、危害程度、原产地、入侵途径等进行了分析。结果表明:梅州城市湿地主要外来入侵植物有16科29属33种,其中菊科植物的数量最多,占入侵植物总数的27.3%;生活型以草本植物为主;有10种入侵植物给当地生态环境带来严重危害;原产地以美洲为主;引入途径主要以人为有意或无意引入为主。在分析城市湿地外来入侵植物现状的基础上,提出了建立入侵植物生态风险评估系统、加强入境检疫、加强地区合作、提高公众防范意识、有效防控和变害为宝等对策,为城市生态及经济的可持续发展提供参考。%The composition, life forms, damage degrees, original districts and invasive routes of alien invasive plant species in urban wetlands of Meizhou City are analyzed in this paper based on our field survey and literature review. The results show that 33 species from 16 families and 29 genera of alien invasive plant species are distributed in the urban wetlands of Meizhou. The Asteraceous plants are the most in number and take up 27.3%of the total species. Herbaceous plant is the dominant life form. In addition, there are 10 species that have caused high degree of threat to the local ecological environment. Most of the alien invasive plant species originally were from the Americas and were introduced intentionally or unintentionally by human beings. On the basis of the research, the strategies for controlling the alien invasive plants are proposed, such as establishing ecological risk evaluating system, enhancing entry quarantine, enhancing regional cooperation, increasing public awareness, effectively preventing and controlling the alien invasive plants, and transforming harmful plants into useful ones, etc. The results of this paper will provide reference for sustainable development of urban ecology and economy of the

  19. 海洋外来物种入侵对南海生态系统的影响及防控对策%Impacts of alien species invasion on the South China Sea ecosystem and related control strategies

    Institute of Scientific and Technical Information of China (English)

    陆琴燕; 刘永; 李纯厚; 魏小岚; 刘勇

    2013-01-01

    外来海洋物种入侵已成为继海洋栖息地破坏之后世界海洋生态环境面临的第二个重大威胁.为了全面了解我国南海外来物种的状况,本文阐述了南海主要外来物种的生物学和生态学特征及其对生态系统的影响,并提出相应的防控对策.结果表明:(1)在我国南海最主要分布和已经报道的外来物种共有35种,多为无意引进.其中,海洋外来藻类最多,为16种,占总种类数的45.7%;其次是海洋污损动物,为11种,占31.4%;外来微生物,为5种,占14.3%;潮间带滩涂植物主要有3种,占8.6%.(2)外来入侵物种主要通过4个方面危害海洋生态系统:弱化海洋生态系统群落结构,降低其物种多样性;改变海洋生态系统遗传多样性,降低其遗传变异性;影响海洋生态系统稳定性,造成外源病害肆虐;加剧海洋生态灾害.本文对南海不同种类外来物种生物学特征分析可为南海外来物种入侵的进一步研究提供基础资料,防控对策的提出可为管理部门制定海洋外来物种入侵管理策略提供参考,以期更好地保护南海海洋生态系统.%Alien species invasion is generally regarded as the second serious threat following habitat destruction to marine ecosystem.This paper elaborated the biological and ecological characters of marine alien species in the South China Sea and the impacts of these species invasion on the South China Sea ecosystem,and put forward the corresponding control strategies.There were totally 35 alien species in the South China Sea,most of which were accidentally introduced species.Among the alien species,alien algae were dominant (16 species,45.7% of the total),followed by fouling animals (11 species,31.4%),alien microorganisms (5 species,14.3%),and intertidal plants (3 species,8.6%).The alien species invasion weakened the community structure and reduced the biodiversity,altered the genetic diversity and decreased the genetic

  20. 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.

  1. Red swamp crayfish: biology, ecology and invasion - an overview

    OpenAIRE

    Tainã Gonçalves Loureiro; Pedro Manuel Silva Gentil Anastácio; Paula Beatriz de Araujo; Catherine Souty-Grosset; Mauricio Pereira Almerão

    2015-01-01

    ABSTRACTAlien species have been transported and traded by humans for many centuries. However, with the era of globalization, biological invasions have reached notable magnitudes. Currently, introduction of alien species is one of the major threats to biodiversity and ecosystem functioning. The North American crayfish Procambarus clarkii is one of the most widely introduced freshwater species in the world, especially due to its high economic importance. It is responsible for great modification...

  2. Beta-thymosin gene polymorphism associated with freshwater invasiveness of alewife (Alosa pseudoharengus)

    Science.gov (United States)

    Michalak, Katarzyna; Czesny, Sergiusz J.; Epifanio, John; Snyder, Randal J.; Schultz, Eric T.; Velotta, Jonathan P.; McCormick, Stephen D.; Brown, Bonnie L.; Santopietro, Graciela; Michalak, Pawel

    2014-01-01

    Predicting the success of a species’ colonization into a novel environment is routinely considered to be predicated on niche-space similarity and vacancy, as well as propagule pressure. The role genomic variation plays in colonization success (and the interaction with environment) may be suggested, but has not rigorously been documented. To test an hypothesis that previously observed ecotype-specific polymorphisms between anadromous and landlocked alewife (Alosa pseudoharengus) populations are an adaptive response to osmoregulatory challenges rather than a result of allele sampling at founding, we examined multiple anadromous and landlocked (colonized) populations for their allelic profiles at a conserved region (3’-UTR end) of a β-thymosin gene whose protein product plays a central role in the organization of cytoskeleton. The putatively ancestral β-thymosin allele was prevalent in anadromous populations, whereas a newly derived allele was overrepresented in landlocked populations; a third allele was exclusive to the anadromous populations. We also conducted a complementary set of salinity exposure experiments to test osmoregulatory performance of the alewife ecotypes in contrasting saline environments. The pattern of variation and results from these challenges indicate a strong association of β-thymosin with colonization success and a transition for species with an anadromous life-history to one with only a freshwater component.

  3. 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.

  4. Growth-form and spatiality driving the functional difference of native and alien aquatic plants in Europe.

    Science.gov (United States)

    Lukács, Balázs A; Vojtkó, Anna E; Mesterházy, Attila; Molnár V, Attila; Süveges, Kristóf; Végvári, Zsolt; Brusa, Guido; Cerabolini, Bruno E L

    2017-02-01

    Trait-based approaches are widely used in community ecology and invasion biology to unravel underlying mechanisms of vegetation dynamics. Although fundamental trade-offs between specific traits and invasibility are well described among terrestrial plants, little is known about their role and function in aquatic plant species. In this study, we examine the functional differences of aquatic alien and native plants stating that alien and native species differ in selected leaf traits. Our investigation is based on 60 taxa (21 alien and 39 native) collected from 22 freshwater units of Hungarian and Italian lowlands and highlands. Linear mixed models were used to investigate the effects of nativeness on four fundamental traits (leaf area, leaf dry matter content, specific leaf area, and leaf nitrogen content), while the influence of growth-form, altitude, and site were employed simultaneously. We found significantly higher values of leaf areas and significantly lower values of specific leaf areas for alien species if growth-form was included in the model as an additional predictor.We showed that the trait-based approach of autochthony can apply to aquatic environments similar to terrestrial ones, and leaf traits have relevance in explaining aquatic plant ecology whether traits are combined with growth-forms as a fixed factor. Our results confirm the importance of traits related to competitive ability in the process of aquatic plant invasions. Alien aquatic plants can be characterized as species producing soft leaves faster. We argue that the functional traits of alien aquatic plants are strongly growth-form dependent. Using the trait-based approach, we found reliable characteristics of aquatic plants related to species invasions, which might be used, for example, in conservation management.

  5. Construction and Application of Basic Data Acquisition and Management System for Fujian Province's Alien Invasive Species%福建外来入侵生物基础数据采集管理系统构建与应用

    Institute of Scientific and Technical Information of China (English)

    陈宏; 赵健; 池美香; 邱荣洲; 翁启勇

    2011-01-01

    针对福建外来入侵生物防控工作中对历史数据管理、部门调查数据协同与交换、数据分析与展示中存在的实际问题,结合“3S”技术(地理信息系统技术、遥感技术和全球定位技术)、移动智能终端、3G移动通信网络等现代信息技术,设计了福建外来入侵生物数据采集与管理的协同工作模式,并开发了福建外来入侵生物基础数据采集管理系统与采集设备.实现了不同的用户对外来入侵生物信息的采集、传输、管理、查询和发布等完整的信息处理流程.在建设过程中完成了156种福建主要外来入侵生物基础数据的收集、整理和数据入库,以期为福建省外来入侵生物风险分析和预警监测提供基础数据来源和技术支撑.%In order to solve the problem about the historical data management, collaboration and exchange department of survey data, data analysis and display of prevention and control of alien invasive species in Fujian province, geographic information systems technology, remote sensing and global positioning systems (the 3S technology), personal digital assistant and third generation mobile communication system were applied to design the data acquisition and management team work model of alien invasive species for Fujian province in this study, and realize the information system and develop data acquisition devices. For different user needs, the system realizes the alien invasive species information processing flow, such as data acquisition, data transmission, data management, data query and publish information. This study has completed to acquire, collate and store 156 alien invasive species records in Fujian province. Implementation and operation of system could provide basic data sources, technology and devices supports for risk assessment and early warning monitor with alien invasive species in Fujian province.

  6. Alien Abductions

    Science.gov (United States)

    Nickell, Joe

    2000-03-01

    Since the beginning of the modern UFO craze in 1947, an elaborate mythology has developed concerning alleged extraterrestrial visitations. ``Flying saucer" sightings (typically involving misperceptions of such mundane phenomena as meteors and research balloons) began to be accompanied in the 1950s by reports from ``contactees," persons who claimed to have had close encounters with, even to have been transported to distant planets by, UFO occupants. By the 1960s came reports of sporadic ``abductions" which have proliferated in correlation with media interest. (Indeed, by interaction between claimants and media the portrayal of aliens has evolved from a multiplicity of types into the rather standardized big-eyed humanoid model.) While evidence of alien contact has often been faked--as by spurious photos, ``crop circles," and the notorious ``Alien Autopsy" film--few alien abduction reports appear to be hoaxes. Most seem instead to come from sincere, sane individuals. Nevertheless, not one has been authenticated, and serious investigation shows that such claims can be explained as sleep-related phenomena (notably ``waking dreams"), hypnotic confabulation, and other psychological factors. As is typical of other mythologies, the alien myth involves supernormal beings that may interact with humans, and it purports to explain the workings of the universe and humanity's place within it.

  7. Invasion risks posed by ornamental freshwater fish trade to southeastern Brazilian rivers

    Directory of Open Access Journals (Sweden)

    André Lincoln Barroso de Magalhães

    Full Text Available A model was developed to assess the risk of invasion of ornamental non-native fishes to six rivers in the state of Minas Gerais, southeastern Brazil, with focus on species popularity. Thirty-nine aquarium shops, in six cities, were visited monthly from January to December 2007. In each city, fish species were identified, and their biology and invasion history information was obtained from the literature. We calculated the annual frequency of occurrence and average number of specimens monthly available in stores. Quarterly water temperature and dissolved oxygen data from 1997 to 2007 were obtained for the Velhas, Muriaé, Uberabinha, Sapucaí-Mirim, Doce and Todos os Santos Rivers from public databases. The invasion risk of each species was assessed through a model comprising nine parameters grouped in four variables: (i Invasiveness (thermal and dissolved oxygen ranges, diet, parental care or fecundity, (ii History of invasions (establishment, (iii Propagule pressure (commercial success, comprising annual frequency of occurrence and number of specimens available monthly at stores, and (iv Invasibility (water temperature and dissolved oxygen in the target river compatible with the species ranges. Of the 345 ornamental fish species for sale, 332 are non-native to either Minas Gerais (n = 151 or Brazil (n = 194. Based on the proposed cutting values, in particular the compatibility between species and recipient thermal ranges, five ornamental non-native species (Cyprinus rubrofuscus, Carassius auratus, Xiphophorus hellerii, Poecilia reticulata, and P. latipinna can potentially invade the Velhas and Muriaé Rivers, four species (Cyprinus rubrofuscus, Carassius auratus, X. helleri, and P. reticulata the Uberabinha River, four species (Cyprinus rubrofuscus, Carassius auratus, X. maculatus, and P. reticulata the Sapucaí-Mirim River, three species (Carassius auratus, X. hellerii, and P. reticulata the Doce River, and three species (Cyprinus rubrofuscus

  8. 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.

  9. The Problem and Status of the Alien Invasive Plants in China%中国外来入侵植物研究现状及存在的问题

    Institute of Scientific and Technical Information of China (English)

    闫小玲; 寿海洋; 马金双

    2012-01-01

    生物入侵是当今各国发展的一大挑战,特别是像中国这样的发展中国家.然而,我们对外来入侵种的本底资料还很不清楚,更缺乏相关的深入调查;对生物入侵所造成的生态和经济影响还没有引起足够的重视,同时也忽视了盲目引种可能带来的各种危害.本文在文献调研的基础上,从外来植物的入侵历史和文化、中国外来入侵植物的调查现状、外米植物入侵对生态安全及经济的影响等方面进行了全面系统的总结,并提出了中国外来入侵植物研究领域存在的问题及应对措施.%The biological invasion has become a major challenge on global development, especially for whole developing country like China. However, the background data of invasive species in China is still far from completed, and the relevant investigation of the Chinese invasive inforatmion has not been fully available yet today. The huge ecological and economic impacts caused by various invasive species have not been fully noticed or observed by the relative institutions and scientists, plus the ignorance of dangerous invasion with the introduction of alien species. Based on various literatures, the history and culture of invasive plant species, their invasive status and impact on ecological security and economic loss in China have been fully reviewed; and the problems existed and mangement measures of alien invasive plants in China have been fully proposed and summarized in order to provide basic information on the management of invasive plant species in China, and appeal to the government and the community to improve their Risk-Prevention strategies and great sense of urgency with alien invasive plants in China.

  10. Hierarchy formation and hormonal profiles in Australoherus facetus, an invasive freshwater fish in Portugal.

    Directory of Open Access Journals (Sweden)

    Flávia Baduy

    2015-11-01

    Full Text Available Australoheros facetus is a highly social neotropical cichlid that is invasive in the Guadiana and Odelouca basins (Southern Portugal. Phenotypic plasticity is believed to be a key component for invasive success. However, its biology remains largely unknown. In this research we aimed to characterize the behaviour and hormone profiles (Testosterone (T, Estradiol (E, 11-keto-testosterone (11KT and Cortisol throughout the formation of stable social groups, a crucial step in the life-history of A. facetus. Fifteen social groups (n=4-6 size matched individuals per group were observed and filmed until stable hierarchies were formed (7 days at different periods of the year. An ethogram was established and a dominance index (DI=wins/ total interactions was used to quantify social dominance. Blood samples were taken from all fish at the beginning and end of the experiment. After the trial period, the animals were sacrificed and the gonads inspected for sex determination. A pair breeding strategy with territorial behaviour was found, and territorial status was attributed to fish that formed a breeding couple and defended an arena. A positive correlation was found between dominance and size for both sexes (length: females R=0.63, males R=0.74; Weight: females R=0.79; males R=0.69; p<0.05. There were no differences between individuals in the initial levels of all hormones, but while T and E showed no evident pattern, final 11KT was higher in territorial males (territorial=2.30ng/mL, non-territorial=1.11ng/mL, p<0.05. Final cortisol were higher in non-territorial males (territorial=96.91ng/mL, non-territorial=163.3ng/mL, p<0.05 and negatively correlated with dominance (R=-0.47, p<0.05. These results suggest that size is the main driver for social dominance and that high social status lowers stress in all fish and increases 11KT secretion in males. Further analysis are in progress to understand the complex reproductive processes and the interspecific

  11. 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.

  12. Risk assessment of non-native fishes in the Balkans Region using FISK, the invasiveness screening tool for non-native freshwater fishes

    Directory of Open Access Journals (Sweden)

    P. SIMONOVIC

    2013-06-01

    Full Text Available A high level of freshwater fish endemism in the Balkans Region emphasizes the need for non-native species risk assessments to inform management and control measures, with pre-screening tools, such as the Fish Invasiveness Screening Kit (FISK providing a useful first step. Applied to 43 non-native and translocated freshwater fishes in four Balkan countries, FISK reliably discriminated between invasive and non-invasive species, with a calibration threshold value of 9.5 distinguishing between species of medium and high risk sensu lato of becoming invasive. Twelve of the 43 species were assessed by scientists from two or more Balkan countries, and the remaining 31 species by a single assessor. Using the 9.5 threshold, three species were classed as low risk, 10 as medium risk, and 30 as high risk, with the latter category comprised of 26 moderately high risk, three high risk, and one very high risk species. Confidence levels in the assessments were relatively constant for all species, indicating concordance amongst assessors.

  13. Occurrence and damage of alien invasive weeds in Guangxi agricultural ecosystem%广西农业生态系统外来入侵杂草发生与危害现状分析

    Institute of Scientific and Technical Information of China (English)

    郭成林; 马永林; 马跃峰; 覃建林

    2013-01-01

    [目的]了解广西农业生态系统外来入侵杂草发生与危害状况,为外来入侵杂草的风险评估与防控提供科学依据.[方法]采用文献资料与野外调查相结合的方法,于2011年10月~2012年9月对广西境内14个地级市80个县区稻田、甘蔗地、木薯地、桑园、果园、蔬菜以及其他作物地外来入侵杂草进行系统调查,调查内容包括外来入侵杂草的种类、分布、生境及危害程度.[结果]查明广西农业生态系统有外来入侵杂草101种,隶属27科74属,其中以菊科最多,有25种,其次为禾本科17种、苋科8种、茄科7种、豆科6种、旋花科和大戟科各5种;从植物性状看,以草本植物为主,有88种,占87.13%;从分布特点看,以全区分布为主,有67种,占66.34%;从危害程度看,危害严重的外来杂草有15种,危害程度中等的有22种.[结论]广西农业生态系统外来杂草种类多、数量大、危害重,建立外来物种监测、风险评估及防控体系是防范外来杂草入侵的有效途径.%[Objective]The study was performed to investigate the occurrence and damage of alien invasive weeds in Guangxi agricultural ecosystem in order to provide references for their risk assessment and further prevention and control.[Method] Based on field investigations and related literatures,systematic study was conducted from October 2011 to September 2012 to investigate variety,distribution,habitat and damage degree of invasive weeds in rice,sugarcane,cassava,mulberry,orchard,vegetable and other crop fields in 80 counties and 14 cities of Guangxi.[Result]A total of 101 species of invasive plants belonging to 74 genus and 27 families were identified in Guangxi farmlands.Amongst them,Compositae was the most invasiveweeds,which was consisted of 25 species and it was followed by Gramineae (17 species),Amaranthaceae (8 species),Solanaceae (7 species),Leguminosae (6 species),Convolvulaceae (5 species) and Euphorbiaceae (5 species

  14. 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 ...

  15. 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 ...

  16. Invasive mechanism and management strategy of Bemisia tabaci(Gennadius) biotype B:Progress report of 973 Program on invasive alien species in China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Bemisia tabaci(Gennadius) biotype B,called a "superbug",is one of the most harmful biotypes of this species complex worldwide.In this report,the invasive mechanism and management of B.tabaci biotype B,based on our 5-year studies,are presented.Six B.tabaci biotypes,B,Q,ZHJ1,ZHJ2,ZHJ3 and FJ1,have been identified in China.Biotype B dominates the other biotypes in many regions of the country.Genetic diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal application.The activities of CarE(carboxylesterase) and GSTs(glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants,which might have increased its resistance to insecticides.The higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host plants.Higher adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein genes.The indigenous B.tabaci biotypes were displaced by the biotype B within 225 d.The asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other biotypes.B.tabaci biotype B displaced Trialeurodes vaporariorum(Westwood) after 4-7 generations under glasshouse conditions.Greater adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of T.vaporariorum.Greater ability of the biotype B to switch to different host plants may enrich its host plants,which might enable it to better compete with T.vaporariorum.Native predatory natural enemies possess greater ability to suppress B.tabaci under field conditions.The kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its parasitoids.The present results provide useful information in explaining the mechanisms of genetic diversity

  17. Invasive mechanism and management strategy of Bemisia tabaci (Gennadius) biotype B: progress report of 973 Program on invasive alien species in China.

    Science.gov (United States)

    Wan, FangHao; Zhang, GuiFen; Liu, ShuSheng; Luo, Chen; Chu, Dong; Zhang, YouJun; Zang, LianSheng; Jiu, Min; Lü, ZhiChuang; Cui, XuHong; Zhang, LiPing; Zhang, Fan; Zhang, QingWen; Liu, WanXue; Liang, Pei; Lei, ZhongRen; Zhang, YongJun

    2009-01-01

    Bemisia tabaci (Gennadius) biotype B, called a "superbug", is one of the most harmful biotypes of this species complex worldwide. In this report, the invasive mechanism and management of B. tabaci biotype B, based on our 5-year studies, are presented. Six B. tabaci biotypes, B, Q, ZHJ1, ZHJ2, ZHJ3 and FJ1, have been identified in China. Biotype B dominates the other biotypes in many regions of the country. Genetic diversity in biotype B might be induced by host plant, geographical conditions, and/or insecticidal application. The activities of CarE (carboxylesterase) and GSTs (glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants, which might have increased its resistance to insecticides. The higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host plants. Higher adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein genes. The indigenous B. tabaci biotypes were displaced by the biotype B within 225 d. The asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other biotypes. B. tabaci biotype B displaced Trialeurodes vaporariorum (Westwood) after 4-7 generations under glasshouse conditions. Greater adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of T. vaporariorum. Greater ability of the biotype B to switch to different host plants may enrich its host plants, which might enable it to better compete with T. vaporariorum. Native predatory natural enemies possess greater ability to suppress B. tabaci under field conditions. The kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its parasitoids. The present results provide useful information in

  18. Invasive mechanism and manasement stratesy of Bemisia tabaci (Gennadius) biotype B: Progress report of 973 Program on invasive alien species in China

    Institute of Scientific and Technical Information of China (English)

    WAN FangHao; CUI XuHong; ZHANG LiPing; ZHANG Fan; ZHANG QingWen; LIU WanXue; LIANG Pei; LEI ZhongRen; ZHANG YongJun; ZHANG GuiFen; LIU ShuSheng; LUO Chen; CHU Dong; ZHANG YouJun; ZANG LianSheng; JIU Min; Lǖ ZhiChuang

    2009-01-01

    Bemisia tabaci (Gennadius) biotype B, called a "superbug", is one of the most harmful biotypes of this species complex worldwide. In this report, the invasive mechanism and management of B. tabaci bio-type B, based on our 5-year studies, are presented. Six B. tabaci biotypes, B, Q, ZHJ1, ZHJ2, ZHJ3 and FJ1, have been identified in China. Biotype B dominates the other biotypes in many regions of the country. Genetic diversity in biotype B might be induced by host plant, geographical conditions, and/or insecticidal application. The activities of CarE (carboxylesterase) and GSTs (glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants, which might have increased its resistance to insecticides. The higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host plants. Higher adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein genes. The in-digenous B. tabaci biotypes were displaced by the biotype B within 225 d. The asymmetric mating in-teractions and mutualism between biotype B and begomoviruses via its host plants speed up wide-spread invasion and displacement of other biotypes. B. tabaci biotype B displaced Trialeurodes vapo-rariorum (Westwood) after 4-7 generations under glasshouse conditions. Greater adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its suc-cessful displacement of T. vaporariorum. Greater ability of the biotype B to switch to different host plants may enrich its host plants, which might enable it to better compete with T. vaporariorum. Native predatory natural enemies possess greater ability to suppress B. tabaci under field conditions. The kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its parasitoids. The present results provide useful information in

  19. 许昌市城郊外来入侵植物调查及危害风险评价%Research and Risk Assessment of Alien Invasive Plants of Xuchang Suburb

    Institute of Scientific and Technical Information of China (English)

    姜罡丞; 王珂; 董东平

    2009-01-01

    The analyses of the invasive plants of Xuchang suburbs show that there are 46 species of invasive plants and they belong to 18 families.They come from North America,South America,Europe and Western Asian in the original.The ways of the invasion include intended introduction of human,non-intended introduction of human activities and nature invasion.The disaster mechanism is mainly affected by the biological characteristics of the plants,appropriate geographical environment and human activities.According to the author's risk assessment system of Xuchang suburbs,21 kinds of alien invasive plants are high risk harm plants and 10 kinds are moderate risk harm plants among 46 alien invasive plants.%对许昌市城郊的外来入侵植物统计分析结果表明:外来入侵植物共有46种,隶属18科;其来源地有南北美洲、欧洲、西亚等地区;入侵途径主要包括人为有意引入、人类活动无意引入和自然侵入;成灾机制则主要受植物本身的生物学特性和适宜的地理环境以及人类活动的影响.据作者建立的许昌市城郊外来入侵植物危害风险评价指标分析:在46种外来入侵植物中,其中有21种属于高风险危害植物,10种属于中风险危害植物.

  20. Species,origins and risk assessment of alien invasive ornamental plants in China%中国外来观赏入侵植物的种类与来源及其风险评价

    Institute of Scientific and Technical Information of China (English)

    王宁; 杜丽; 周兵; 闫小红

    2013-01-01

    Based on literature and previous studies, risks of alien invasive ornamental plants in China were assessed for the first time, taking into consideration of their composition, growth characteristics, detection or in-troduction time and place, and geographical origin. The results show that there are 84 invasive plants belonging to 30 families in China. Most of them were part of Asteraceae, Onagraceae, Leguminosae, Solanaceae and Conv-olvulaceae. Perennial and annual herbs account for the majority. Most of these ornamental plants could repro-duce by seeds and a part of the plants have asexual reproduction ability. They were mainly detected in or intro-duced to China from 1890 to 1969 in coastal provinces and Yunan Province of China. America was the primary geographical origin of these alien invasive plants. The number of the strongest invasive plants, the stronger inva-sive plants and the weaker invasive plants are respectively 8 , 56 and 20 . The majority of the alien invasive orna-mental plants are moderately dangerous.%通过查阅相关文献资料,整理分析中国外来观赏入侵植物的种类组成、生长特性、首次发现或引入时间及地点、地理来源,并对其进行风险评价。结果表明:目前中国外来观赏入侵植物共计84种,隶属30科,其中以菊科、柳叶菜科、豆科、茄科和旋花科植物为主,且多年生和一年生草本植物占据多数;入侵植物繁殖方式多以种子进行繁殖,部分兼具无性繁殖能力;首次发现或引入外来观赏植物时间较集中于1890-1969年,地点主要为中国一些沿海省份以及云南省,其地理上多来源于美洲;属于高、中、低入侵危害等级的外来观赏植物分别有8种、56种和20种,中等风险入侵植物所占比例较高。

  1. Current status of invasive alien pests in Guangxi Province and Vietnam%广西及越南农业外来有害生物入侵现状

    Institute of Scientific and Technical Information of China (English)

    于永浩; 高旭渊; 曾宪儒; 龙秀珍; 韦德卫; 覃建林; 蔡健和; 曾涛

    2016-01-01

    【背景】广西地理环境独特,与越南水陆相连,气候、作物等条件相似,边境贸易往来频繁,致使其成为我国遭受外来有害生物入侵最严重的地区之一。【方法】通过本底调查,分析总结了广西农业外来有害生物入侵的现状。【结果】广西主要入侵动物26种,入侵微生物18种,入侵植物21种,高风险入侵物种包括辣椒实蝇、木薯绵粉蚧、扶桑绵粉蚧、稻水象甲、黄瓜绿斑驳花叶病毒等;来自越南的潜在危险性有害生物共38种。【结论与意义】广西受外来有害生物入侵的风险加剧,并有进一步扩散蔓延的趋势。提出应对入侵生物的综合防控对策,为广西外来入侵有害生物的防控提供参考。%Background] With the unique geographical conditions, and because of the more and more frequent border trade, similar climate and cropping systems in Guangxi and Vietnam, Guangxi Province has become one of the most threatened areas by the inva-sion of alien species in China. [Method] This paper analyzed the current status of the biological invasions in Guangxi via a back-ground survey. [Result] There were 26 species of invasive animals, 18 species of microorganism and 21 species of weeds. Some harmful invasive species of high risk includes the chilifruit fly [ Bactrocera latifrons ( Hendel) ] , the cassava mealybug ( Phenacoccus manihoti Matile-Ferrero) , the solenopsis mealybug ( Phenacoccus solenopsis Tinsley) , the rice water weevil ( Lissorhoptrus oryzophi-lus Kuschel) , and the Cucumber green mottle mosaic virus. 38 potentially hazardous pests from Vietnam are listed. [Conclusion and significance] Risk of harmful invasive species to Guangxi aggravated, with further spread tendency. Comprehensive strategy about the invasive alien pest was proposed, which provided some ideas controlling the invasive alien pests in Guangxi Province.

  2. Alien Invasive Plants in Nanchang Urban Green Land and Its Preventive Measures%南昌城市绿地外来入侵植物及其防治对策

    Institute of Scientific and Technical Information of China (English)

    朱碧华; 杨凤梅

    2012-01-01

    Alien plants invasion,which has caused wide public concern all over the world,threatening the stability and the bearing capability of ecosystem.Moreover,it harming the economic structure of human society and human health,and the loss is beyond estimation.The urban green land is easily influenced of alien plants invasion as a comparatively weaker self-regulate ecosystem.The common species of alien invasive plants in Nanchang urban green land were introduced in this paper,and its attacking ways and the harmful result to the urban green ecosystem were discussed,meanwhile,some relevant prevention measures were put forward.%植物入侵威胁生态系统的稳定性,影响生态系统的承载力,危害人类社会经济结构以及人类健康,造成了无法估量的损失,已经引起全球的普遍关注。城市绿地作为一个自我调节能力相对较弱的生态系统,对外来植物入侵的防范能力比较低,受影响的程度会更大。介绍南昌城市绿地中外来入侵植物的常见种类,探讨外来植物的入侵途径和对城市绿地生态系统的危害,并提出相应的预防措施。

  3. 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.;

  4. Invasive forest species

    Science.gov (United States)

    Barbara L. Illman

    2006-01-01

    Nonnative organisms that cause a major change to native ecosystems-once called foreign species, biological invasions, alien invasives, exotics, or biohazards–are now generally referred to as invasive species or invasives. invasive species of insects, fungi, plants, fish, and other organisms present a rising threat to natural forest ecosystems worldwide. Invasive...

  5. 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

  6. 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 and transparent priorities for clearing in the face of multiple and sometimes conflicting demands. This study used the analytic hierarchy process (a multi-criteria decision support technique) to develop and rank criteria for prioritising alien plant control...

  7. A Preliminary Study on the Alien Invasive Plant Species in Huangshanlu Forest Park,Guangzhou%广州南沙黄山鲁森林公园外来入侵植物初步研究

    Institute of Scientific and Technical Information of China (English)

    李海生; 蔡惠娟; 李济明; 邓华源; 钟碧玲

    2015-01-01

    Based on field investigation and literature research,the species,life form,growth situation, the ways of invasion and hazard situation of invasive plants in Huangshanlu Forest Park were preliminarily studied.The results showed that there were thirty species of alien invasive plants belonging to 29 genera of 14 families in Huangshanlu Forest Park.Of them,six alien invasive plant species belong to Poaceae and seven belong to Asteraceae,occupying 43.3% of the total number of invasive plants.Analysis of the life form showed that the most dominant plants were terrestrial herbs (21 species),then shrubs (4 species), vines(3 species),trees and aquatic herbs(1 species respectively),all of them mainly growing in the heavily disturbed areas.In addition,with the analysis of growth characteristics and distribution of ecological traits in the field,seven alien invasive species were evaluated to be at the highest degree of threat to the local biodiversity,nine at the medium,and fourteen at the lowest.Based on the origin,15 species from Tropical America,occupied 50% of the total alien invasive species in Huangshanlu Forest Park.%通过野外调查,结合文献资料,对广州南沙黄山鲁森林公园入侵植物的种类、生活型、生境状况、入侵途径以及危害状况等进行了初步研究.结果表明:黄山鲁森林公园现有外来入侵植物30种,隶属14科29属,其中禾本科(6种)、菊科(7种)植物占总入侵植物种数的43.3%.对入侵植物的生活型分析发现,陆生草本植物最多(21种),其次为灌木(4种)、藤本植物(3种),乔木和水生草本种类最少(各1种),入侵植物主要生长在受人为干扰较大的区域.此外,对入侵植物生长特性及分布等生态学特征分析,可将其对黄山鲁森林公园生物多样性危害程度大致分为3级,其中危害严重的有7种,危害中等的有9种,危害较轻的有14种.从原产地分析来看,15种来自于热带美洲地区,

  8. 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.

  9. 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.

  10. 北京松山自然保护区外来入侵植物研究%The Research of Alien Invasive Plant in Beijing Songshan Nature Reserve

    Institute of Scientific and Technical Information of China (English)

    刘佳凯; 姚可侃; 张容; 夏阳; 王慧慧; 张振明; 吴计贵; 蒋万杰

    2012-01-01

    为了对松山地区外来植物进行长期有效的监测和管理,防止其对当地的自然生态系统造成破坏,对松山国家级自然保护区的植物进行了详细的样方调查,并对保护区外来入侵植物的分布和相对盖度进行分析.结果表明:松山自然保护区共发现外来植物入侵植物23种,隶属于12科17属,其中大麻(Cannabis sativa)、反枝苋(Amaranthus retroflexus)、萱草(Hemerocallis fulva)、洋槐(Robinia pseudoacacia)、荷包豆(Phaseolus coccineus)等较为常见,影响外来植物入侵的主要因素是道路修建和坡向.该区域的外来物种的各种群规模不大,且多集中在人为活动较为频繁的实验区,对保护区内重点保护的天然次生油松林以及落叶阔叶次生林的生态系统并不存在特别大的威胁.%In order to establish a long-term monitoring mechanism of exotic plants in Songshan Nature Reserve, the author conducted this study, through the survey and the analysis of distribution and relative coverage of alien invasive plants in Songshan Nature Reserve, the results showed that 23 species of alien invasive plants were found, belonging to 12 families and 17 generas. Among them marijuana (Cannabis sativa), redroot amaranth (Amaranthus retroflexus), day lily (Hemerocallis fulva), acacia {Robinia pseudoacacia) and scarlet runner bean (Phaseolus coccineus) were more common. The road construction was the first factor, which influenced and promoted the distribution of alien plants. The next factor was the aspect. Research showed that the alien species population scale was not big and the adverse impact on the local ecological system was not obvious.

  11. 外来入侵植物小飞蓬化感作用机理研究的进展%The Progress of Studies on the Allelopathy Mechanism of Alien Invasive Plant Conyza Canadensis ( L. ) Cronq.

    Institute of Scientific and Technical Information of China (English)

    张海燕; 罗鑫; 张敏

    2015-01-01

    入侵植物会损害环境生态系统,影响生物的多样性,给农业生产带来严重的经济损失.目前,虽然入侵植物的化感作用研究较多,但是很多缺乏对化感作用的深入研究.结合国内外入侵植物的研究进展,该研究阐述了小飞蓬的研究现状、化感物质的分离鉴定方法以及入侵机理研究的进展.参24.%Alien invasive plants can damage the ecological environment system,have influence on the biological diversity and bring serious economic losses to the agricultural production. At present,there are many studies on the allelopathic effect of the invasive plants,but lack of deep research on the mechanism of allelopathy. Combined with the research progress of invasive plants at home and abroad,this paper in-troduce research actuality, methods of isolation, identification allelochemicals and the progress in the mechanism research of Conyza Canadensis. 24refs.

  12. Impact of multiple anthropogenic stressors on freshwater: how do glyphosate and the invasive mussel Limnoperna fortunei affect microbial communities and water quality?

    Science.gov (United States)

    Pizarro, Haydée; Di Fiori, Eugenia; Sinistro, Rodrigo; Ramírez, Marina; Rodríguez, Patricia; Vinocur, Alicia; Cataldo, Daniel

    2016-01-01

    The study of the joint effect of multiple anthropogenic stressors is important because the emerging consequences are often unpredictable on the basis of knowledge of single effects. We explored the joint impact of glyphosate and the invasive golden mussel Limnoperna fortunei on freshwater phytoplankton, bacterioplankton and periphyton, and on the physical and chemical properties of the water. We manipulated both stressors simultaneously in a 25-day experiment using outdoor mesocosms; we assayed technical-grade glyphosate acid at four concentrations: 0, 1, 3 and 6 mg gly L(−1) under scenarios with and without mussels. The addition of the glyphosate significantly increased total phosphorus according to the concentration used; the high clearance rate of L. fortunei significantly decreased phytoplanktonic abundance leading to low values of turbidity. The mussel significantly stimulated the development of filamentous green algae (metaphyton). Interestingly, the combined effect revealed that L. fortunei accelerated the dissipation of glyphosate, which showed a 4-fold decrease in its half-life; this promoted the rapid bioavailability of glyphosate-derived phosphorus in the water. The interaction had a synergistic effect on soluble reactive phosphorus concentrations and was directly dependent on the concentration of glyphosate. A synergistic effect was also observed on bacterioplankton, water turbidity and metaphyton, thus inducing enhanced and rapid eutrophication. The ability of mussels to reduce glyphosate in water may be valued as positive, but our results allow us to predict that the invasion of Limnoperna fortunei in natural freshwater systems contaminated by glyphosate will accelerate the negative impact of the herbicide associated with eutrophication.

  13. Marine incursion: the freshwater herring of Lake Tanganyika are the product of a marine invasion into west Africa.

    Directory of Open Access Journals (Sweden)

    Anthony B Wilson

    Full Text Available The spectacular marine-like diversity of the endemic fauna of Lake Tanganyika, the oldest of the African Great Lakes, led early researchers to suggest that the lake must have once been connected to the ocean. Recent geophysical reconstructions clearly indicate that Lake Tanganyika formed by rifting in the African subcontinent and was never directly linked to the sea. Although the Lake has a high proportion of specialized endemics, the absence of close relatives outside Tanganyika has complicated phylogeographic reconstructions of the timing of lake colonization and intralacustrine diversification. The freshwater herring of Lake Tanganyika are members of a large group of pellonuline herring found in western and southern Africa, offering one of the best opportunities to trace the evolutionary history of members of Tanganyika's biota. Molecular phylogenetic reconstructions indicate that herring colonized West Africa 25-50MYA, at the end of a major marine incursion in the region. Pellonuline herring subsequently experienced an evolutionary radiation in West Africa, spreading across the continent and reaching East Africa's Lake Tanganyika during its early formation. While Lake Tanganyika has never been directly connected with the sea, the endemic freshwater herring of the lake are the descendents of an ancient marine incursion, a scenario which may also explain the origin of other Tanganyikan endemics.

  14. Identifying factors linked to the occurrence of alien gastropods in isolated woodland water bodies.

    Science.gov (United States)

    Spyra, Aneta; Strzelec, Małgorzata

    2014-03-01

    Biological invasions are a significant component of human-caused global change and is widely regarded as one of the main threats to natural biodiversity. Isolated anthropogenic water bodies created in the areas that are deprived of natural freshwater habitats allow the survival and reproduction of alien species on newly settled sites. They are often small with water level fluctuations causing frequent environmental disturbances. The colonisation success may be the result of the rate of their degradation. The aims of the study were to determine the environmental conditions that affect the existence of alien species of gastropods in this type of aquatic environment and to examine whether the occurrence of non-native species affects the community structure of the native species. This study made it possible to group woodland ponds according to the occurrence of the three invasive species in snail communities and discuss the environmental conditions present in these pond types. Analysis of water properties emphasised the distinctiveness of the selected pond types. In ponds of the Potamopyrgus antipodarum type, we found the highest values of some parameters mainly hardness, conductivity, and content of calcium and chlorides, in contrast with the Physella acuta type, which were characterised by the lowest values except for phosphates and nitrites. In the Ferrissia fragilis type, we found the highest nitrate content. Data on the occurrence of alien species in different water environments play an important role in actions which are taken to prevent new invasions and spread of non-native species as well as to reduce future impacts of invaders.

  15. Application of FISK, an invasiveness screening tool for non-native freshwater fishes, in the Murray-Darling Basin (southeastern Australia).

    Science.gov (United States)

    Vilizzi, Lorenzo; Copp, Gordon H

    2013-08-01

    The Fish Invasiveness Scoring Kit (FISK) is currently one of the most popular pre-screening tools for freshwater fishes. A recent upgrade has ensured its wider climatic relevance to countries with subtropical regions. This enhancement is of particular importance to Australia, which encompasses tropical, arid, and temperate zones, and where the introduction of non-native fish species poses a significant risk to biodiversity. In this study, 55 fish species previously evaluated in a U.K.-based calibration of FISK are reassessed for their potential invasiveness in the Murray-Darling Basin (MDB; southeastern Australia), the continent's largest catchment encompassing arid and temperate climates. Approximately half of the species were classed as "medium risk" and the other half as "high risk," and the ≥19 threshold previously identified from the calibration study was confirmed. The three highest scoring species (common carp Cyprinus carpio carpio, goldfish Carassius auratus, and eastern mosquitofish Gambusia holbrooki) were those already present and invasive in the area, whereas nearly half of the tropical and subtropical species had lower scores compared to U.K. assessments, possibly because of climate change predictions of drier conditions across the MDB. There were some discordances between FISK and two Australian-based assessment protocols, one of which is qualitative and the other represents a simplified version of FISK. Notably, the Australian origins of FISK should provide for an additional reason for further applications of the tool in other RA areas (i.e., drainage basins) of the continent, ultimately encouraging adoption as the country's reference screening tool for management and conservation purposes.

  16. 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.

  17. Fine-tuning for the tropics: application of eDNA technology for invasive fish detection in tropical freshwater ecosystems.

    Science.gov (United States)

    Robson, Heather L A; Noble, Tansyn H; Saunders, Richard J; Robson, Simon K A; Burrows, Damien W; Jerry, Dean R

    2016-07-01

    Invasive species pose a major threat to aquatic ecosystems. Their impact can be particularly severe in tropical regions, like those in northern Australia, where >20 invasive fish species are recorded. In temperate regions, environmental DNA (eDNA) technology is gaining momentum as a tool to detect aquatic pests, but the technology's effectiveness has not been fully explored in tropical systems with their unique climatic challenges (i.e. high turbidity, temperatures and ultraviolet light). In this study, we modified conventional eDNA protocols for use in tropical environments using the invasive fish, Mozambique tilapia (Oreochromis mossambicus) as a detection model. We evaluated the effects of high water temperatures and fish density on the detection of tilapia eDNA, using filters with larger pores to facilitate filtration. Large-pore filters (20 μm) were effective in filtering turbid waters and retaining sufficient eDNA, whilst achieving filtration times of 2-3 min per 2-L sample. High water temperatures, often experienced in the tropics (23, 29, 35 °C), did not affect eDNA degradation rates, although high temperatures (35 °C) did significantly increase fish eDNA shedding rates. We established a minimum detection limit for tilapia (1 fish/0.4 megalitres/after 4 days) and found that low water flow (3.17 L/s) into ponds with high fish density (>16 fish/0.4 megalitres) did not affect eDNA detection. These results demonstrate that eDNA technology can be effectively used in tropical ecosystems to detect invasive fish species.

  18. 基于物种生态位与物质能量流互动机制对外来入侵植物的探讨%A Study on Alien Invasive Plants from the Interactive Mechanism between Species Niche and Material/Energy Flow

    Institute of Scientific and Technical Information of China (English)

    陈剑; 喻庆国; 杨宇明

    2011-01-01

    [目的]为揭示外来植物入侵机制的本质.[方法]本文以物种生态位与环境物质能量流为基本研究参量,分析外来植物入侵的内在机制.[结果]认为通常情况下外来入侵植物缺乏明确的定义标准和有效防治方法.[结论]外来入侵植物的泛滥取决于该物种生态位在空间上是否获得连续的满足,以此为基础提出了相应的防治措施,对构建"柱网模型"提出设想,并对外来入侵植物概念本身提出讨论.%[Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic mechanism of alien plants invasion.[Result]Most of the invasive plants have not been explicitly defined and their effective control methods not brought forward.[Conclusion]Overrun of alien invasive plants depends on whether the niche of a species could be continuously met at spatial level.Based on this we put forward corresponding control measures, proposed an assumption to establish a cylinder-network model and discussed the definition of alien invasive plants.

  19. 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.

  20. Biological and Ecological Characteristics of an Invasive Alien Species Spartina in Yellow River Delta%黄河三角洲外来入侵物种米草的生物学与生态学特性

    Institute of Scientific and Technical Information of China (English)

    石东里; 田家怡; 陈印平

    2009-01-01

    In Yellow River Delta,the biological and ecological characteristics of an invasive alien spe-cies spartina were investigated. The results showed that the stem of spartina is tenacious and many gas chambers are in epidermal parencbyma of its rhizome. These characteristics ensure that it can live in flooding conditions. Salt gland that is under surface of its leaf and can secret and discharge salt. Water loss can make seed fail to germination. Its capability of asexual reproduction is strong and that is the bio-logical base of its spreading. Its euryhalinity, submergence tolerance, high adaptability and reproductive capacity,strong high invasion capacity and great ecological amplitude are the ecological base of its inva-sion and development.%对黄河三角洲外来入侵物种米草的生物学、生态学特性进行了观测和研究.结果表明:米草茎秆坚韧,不易倒伏;根状茎表皮薄壁组织内有许多气腔,与淹水条件下生活的习性相适应;米草叶背面有盐腺,便于泌盐和排盐;米草种子失水即失去萌发力,无性繁殖力强,是其扩散的生物学基础;米草的广盐性、耐淹性、高适应性、强繁殖扩散能力、强竞争入侵能力、生态幅宽,是其入侵和爆发的生态学基础.

  1. A Research Review of Invasive Mechanism of Alien Plant Ambrosia Artemisiifolia and Its Present Situation%外来植物豚草的入侵机理研究进展及其现状

    Institute of Scientific and Technical Information of China (English)

    柏祥; 刘传才; 塔莉; 王连龙

    2015-01-01

    从外来植物的入侵性和生境的可入侵性两方面综述了外来植物豚草的入侵机理研究进展,分析了豚草在秦皇岛地区的现状,以中国环境管理干部学院新校区为例调查了人类活动干扰对豚草的影响。豚草的入侵性与其自身所具有的生理生态学特性密切相关,生境的可入侵性则与其群落特征和受干扰程度等因素有关。目前豚草是秦皇岛地区自然群落的建群种,没有表现出入侵性。新校区调查结果表明:豚草在自然群落中零星分布,但受到人类活动干扰的生境中豚草表现出一定的优势度。因此,在豚草防治中应防止人类活动的过度干扰影响,以保护当地的生态环境。%A research review was presented on invasive mechanism of alien plant Ambrosia art-emisiifolia in terms of its invasiveness and the habitat invisibility. The present situation of the plant was analyzed in Qinhuangdao region, and the new campus was taken as an example to inves-tigate the effects of human activity disturbance on A. artemisiifolia. The invasiveness of A. artemisiifolia was closely related to its ecophysiological characteristics, while the habitat invisibility was impacted by community characteristics and disturbance degree. In present, the plant was a community construction species in this region, and showed no invasion. The investigated results showed that A. artemisiifolia distributed sporadically in the natural community. However, in the habitat disturbed by human activities, the plant had relatively high advantage. Therefore, excessive human activity disturbance should be prevented to control the invasive plant, by which to protect the local ecological environment.

  2. Legislation for Prevention of Alien Species Invasion%预防外来物种入侵的立法对策

    Institute of Scientific and Technical Information of China (English)

    渠烨

    2011-01-01

    This paper analyzed the present situation of prevention of alien species in China, pointed out the legislative maladies of non special laws, existent deviation and limited scope. It put forward the countermeasures on definiting legislative aims,making special laws and middle and long term planning, expanding coverage,improving laws and regulations and acclimating international situation.%对我国目前预防外来物种入侵问题的现状进行了分析,指出了我国在预防外来物种入侵立法上没有专门的针对性法律,立法目的有偏差、法律涉及范围有限的弊病,提出了明确立法目的、制订专项立法与中长期规划、适当扩大相关法律覆盖范围、完善法律法规和顺应国际形势的立法对策.

  3. 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.

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

    Directory of Open Access Journals (Sweden)

    Ivan Deriu

    2017-07-01

    Full Text Available 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 partnership and scientific literature. The ownership of the data remains with its source, which is properly cited and linked. The process of data harvesting is performed through the EASIN Data Broker system, which retrieves the information related to alien species data in Europe and stores them in a normalized database structure. Data are subsequently refined through validation, cleansing, and standardization processes and finally stored in the EASIN Geodatabase. All data are finally visualized and shown in occurrence maps at different levels of spatial visualization. Analysis of the data contained in the EASIN Geodatabase through flexible web services offered by the system has already provided useful input in scientific works and policies on biological invasions. Data from European Union (EU member state official surveillance systems, within the framework of the EU Regulation 1143/2014 on invasive alien species, are expected to contribute to the update of the EASIN Geodatabase. In addition, data from citizen science initiatives will further enrich the Geodatabase after appropriate validation. In this article, we describe and discuss the technical aspects, data flow and capabilities of the EASIN Geodatabase.

  5. Studies on Flora Alien Invasive Plants and Disastrous Mechanisms in Wanzhou, Chongqing%重庆市万州区入侵植物区系特征与成灾机制研究

    Institute of Scientific and Technical Information of China (English)

    余顺慧; 邓洪平

    2011-01-01

    According to the outside invading Plant' s final research of Wanzhou it indicates: (1) There are 45 species of flora alien invasive plants which have been already known at present, they belong to 35 genera and 20 families in Wanzhou; (2) The flora shows an obvious tropic characteristics; (3) Most of them are produced in America. Accordingly, The outside causing disaster invading plant's mechanism in Wanzhou has shown the close connection being a geographical feature component with area, has drawn attention in responding to in area vegetation process besides introducing a fine variety.%采取野外样方调查和资料分析方法,对重庆市万州区入侵植物区系特征及其成灾机制进行研究.结果表明:①万州区有入侵植物共20科、35属、45种;②该区入侵植物在科属分布区类型上除世界分布外,主要为热带分布;③入侵植物大部分来源于美洲.该文还探讨了万州区入侵植物的成灾机制与其区系地理成分之间的密切联系.

  6. The Roots Of Alienation

    Science.gov (United States)

    Bronfenbrenner, Urie

    1973-01-01

    Alienation in our society takes several forms--withdrawal, hostility, or efforts to reform. The author traces the roots of alienation to our neglect of many of the needs of children, particularly their need for interaction with adults. Among his many recommendations are: modified work schedules to permit more time with children and systems for…

  7. The aliens are hiding

    Science.gov (United States)

    2015-06-01

    In reply to the physicsworld.com news story “Trail goes cold on alien hotspots, for now” (28 April, http://ow.ly/MeOpZ; see also p5), which described the results of a survey that looked for unexplained pockets of infrared radiation that could have been produced by advanced alien civilizations.

  8. Alienation and Education.

    Science.gov (United States)

    Reimanis, Gunars

    This paper reviews the author's research on the role of certain aspects of alienation in education. The first part of the paper discusses similarities between anomie and locus of reinforcement control, as they assess the normlessness and powerlessness aspects of alienation. The second part reports results from studies attempting to modify one's…

  9. First Report of Outbreaks of the Fall Armyworm Spodoptera frugiperda (J E Smith) (Lepidoptera, Noctuidae), a New Alien Invasive Pest in West and Central Africa

    Science.gov (United States)

    Sankung, Sagnia B.; Togola, Abou; Tamò, Manuele

    2016-01-01

    The fall armyworm Spodoptera frugiperda is a prime noctuid pest of maize on the American continents where it has remained confined despite occasional interceptions by European quarantine services in recent years. The pest has currently become a new invasive species in West and Central Africa where outbreaks were recorded for the first time in early 2016. The presence of at least two distinct haplotypes within samples collected on maize in Nigeria and São Tomé suggests multiple introductions into the African continent. Implications of this new threat to the maize crop in tropical Africa are briefly discussed. PMID:27788251

  10. Controling measures on invasive alien plant "Spartina alterniflora"%外来入侵植物——互花米草的控制措施

    Institute of Scientific and Technical Information of China (English)

    林嵩

    2012-01-01

    This article summarized some controling measures on Spartina alterniflora in the domestic and foreign, including physical, chemical, biological, bio-substitution methods. In connection with the existing problems, it is proposed that the comprehensive prevention and control measures could reach the ideal results to control spartina, alterniflorain invasion.%综述了国内外控制互花米草入侵采取的措施,其中包括物理、化学、生物和生物替代等措施,并针对存在的问题,提出控制互花米草的综合措施。

  11. Freshwater Macroinvertebrates.

    Science.gov (United States)

    Nalepa, T. F.

    1978-01-01

    Presents a literature review of freshwater biology particularly freshwater macroinvertebrates and their effect on water pollution, covering publications of 1976-77. A list of 158 references is also presented. (HM)

  12. Freshwater fishes of Tsitsikamma National Park

    Directory of Open Access Journals (Sweden)

    I.A. Russell

    2002-12-01

    Full Text Available This study aimed to determine the distribution and relative abundance of freshwater fishes in the Tsitsikamma National Park. Fish assemblages in six river systems were sampled in 2001, with a total of 323 fish from eight species recorded. Indigenous fish collected included four freshwater species (Pseudobarbus afer, Pseudobarbus tenuis, Sandelia capensis, Anguilla mossambica, three estuarine species (Monodactylus falciformis, Caffrogobius gilchristi, Myxus capensis, and one alien (Micropterus salmoides. One additional indigenous species (Galaxias zebratus and two aliens (Salmo trutta, Oncorhynchus mykiss could potentially occur within the park. The topography and locality of the park presents a unique opportunity to meaningfully conserve the endangered P. tenuis as well as other fish characteristic of the eastern reaches of the Cape Floristic Region. Management action is required to minimise opportunities for further establishment and spread of alien fish species and to conserve indigenous fish assemblages within the park.

  13. First record of Aequorea macrodactyla (Cnidaria, Hydrozoa from the Israeli coast of the eastern Mediterranean Sea, an alien species indicating invasive pathways

    Directory of Open Access Journals (Sweden)

    Gur Mizrahi

    2015-07-01

    Full Text Available The species of Aequorea attract much scientific interest as they contain the unique Green Fluorescent Protein (GFP. In this work we describe for the first time the discovery of a hydrozoan jellyfish belonging to the genus Aequorea from the Israeli eastern Mediterranean that contains and exhibits fluorescent protein. Finding Aequorea macrodactyla (Brandt, 1835 in the eastern Mediterranean indicates that changes are occurring in the gelatinous fauna of this area. This hydromedusa is known in the seas adjoining the Mediterranean though most of its records are more than four decades old. We examined and identified the newly discovered Israeli Aequorea species by combining two phylogenetic systems, traditional morphological phylogeny and molecular phylogenetics. The molecular identification determined that the species is A. macrodactyla but with minor genetic differences in the mtDNA 16S gene marker. A 1% difference between the Israeli and the Japanese A. macrodactyla was demonstrated, which suggests that the genetic difference between the Israeli and the Japanese population is small but existent. Invasive pathways for this jellyfish were examined by phylogenetic and taxonomic relationships with similar Cnidaria. The results indicate introduction from the Indo-Pacific as invasive pathway, probably by human transportation, and the discovery of A. macrodactyla in the eastern Mediterranean Sea could be interpreted as part of the changes in marine biota as a result of cumulative effects of anthropogenic and global changes that affect the eastern Mediterranean basin.

  14. Climate change and biological invasions: evidence, expectations, and response options.

    Science.gov (United States)

    Hulme, Philip E

    2017-08-01

    A changing climate may directly or indirectly influence biological invasions by altering the likelihood of introduction or establishment, as well as modifying the geographic range, environmental impacts, economic costs or management of alien species. A comprehensive assessment of empirical and theoretical evidence identified how each of these processes is likely to be shaped by climate change for alien plants, animals and pathogens in terrestrial, freshwater and marine environments of Great Britain. The strongest contemporary evidence for the potential role of climate change in the establishment of new alien species is for terrestrial arthropods, as a result of their ectothermic physiology, often high dispersal rate and their strong association with trade as well as commensal relationships with human environments. By contrast, there is little empirical support for higher temperatures increasing the rate of alien plant establishment due to the stronger effects of residence time and propagule pressure. The magnitude of any direct climate effect on the number of new alien species will be small relative to human-assisted introductions driven by socioeconomic factors. Casual alien species (sleepers) whose population persistence is limited by climate are expected to exhibit greater rates of establishment under climate change assuming that propagule pressure remains at least at current levels. Surveillance and management targeting sleeper pests and diseases may be the most cost-effective option to reduce future impacts under climate change. Most established alien species will increase their distribution range in Great Britain over the next century. However, such range increases are very likely be the result of natural expansion of populations that have yet to reach equilibrium with their environment, rather than a direct consequence of climate change. To assess the potential realised range of alien species will require a spatially explicit approach that not only

  15. Use of non-timber forest products from invasive alien Prosopis species(mesquite) and native trees in South Africa: implications for management

    Institute of Scientific and Technical Information of China (English)

    Ross; T; Shackleton; David; C; Le; Maitre; Brian; W; van; Wilgen; David; M; Richardson

    2015-01-01

    Background: Prosopis species have been introduced to many areas outside their native range to provide benefits to local communities. Several Prosopis species and their hybrids(hereafter "mesquite") have, however, become naturalised and invasive and now generate substantial costs. Management options are limited because of the complex conflicts of interest regarding benefits and costs. Management policies and strategies must take account of such conflicts, but further insights are needed on the dimensions of uses and impacts before such information can be usefully applied. Current policy in South Africa allows for the growth and use of mesquite in one province,but not in others where its control is mandatory. We report on a study to quantify the direct use and perceptions of non-timber forest products(NTFPs) from mesquite and native trees in South Africa.Methods: Semi-structures household interviews were conducted with various stakeholder groups to identify what tree products are used, to ascertain amounts used as well as to gauge perceptions of natural resource use between different tree species and use over time.Results: The direct household use value of native trees was higher than that of mesquite, and local stakeholders attached greater value to products from native trees than from mesquite. Therefore, native trees are and will still be preferentially harvested, and mesquite is unlikely to offer protection to native species by providing an alternative source of products. Mesquite pods do, however, provide valuable additional resources(fodder and medicinal products). The use of both native trees and mesquite is decreasing as the incomes of poorer households rise and as alternative energy sources become available. The benefits and reliance on mesquite are not as high as previously assumed and the impacts from mesquite invasions create large problems for local communities.Conclusion: This study provides further evidence that the impacts of mesquite exceed the

  16. Attacking invasive grasses

    Science.gov (United States)

    Keeley, Jon E.

    2015-01-01

    In grasslands fire may play a role in the plant invasion process, both by creating disturbances that potentially favour non-native invasions and as a possible tool for controlling alien invasions. Havill et al. (Applied Vegetation Science, 18, 2015, this issue) determine how native and non-native species respond to different fire regimes as a first step in understanding the potential control of invasive grasses.

  17. Alien fish species in reservoir systems in Turkey: a review

    Directory of Open Access Journals (Sweden)

    Deniz Innal

    2012-12-01

    Full Text Available Turkey’s natural river systems have been anthropogenically altered in the past century. Native fish communities of river systems have comeunder increasing pressure from water engineering projects, pollution, overfishing and the movements of alien fish species. Introduction ofalien fishes is one of the main threats to the survival and genetic integrity of native fishes around the world. In Turkey, alien freshwater fish are continuing to increase in number of species, abundance, and distribution. The present paper reviews fish stocking studies in Turkey’s reservoirs.

  18. Life under alien skies

    Science.gov (United States)

    Dartnell, Lewis

    2012-04-01

    As the number of confirmed extrasolar planets increases, so does the likelihood that some of them will harbour life. Lewis Dartnell describes some preliminary - but increasingly well founded - efforts to predict what alien plants and animals might look like.

  19. 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.

  20. 中国西南纵向岭谷区外来入侵植物对生物多样性的影响%The Impacts of the Alien Invasive Plants on Biodiversity in Longitudinal Range-Gorge Region of Southwest China

    Institute of Scientific and Technical Information of China (English)

    陆树刚; 徐成东; 董晓东; 段玉清; 王奕

    2006-01-01

    This paper deals with the impacts of the alien invasive plants on biodiversity in longitudinal range-gorge region of Southwest China. The longitudinal range-gorge region of Southwest China is a critical region for reserving biodiversity and now this region has become a highly endangered region with more than 70 species of alien invasive plants. Among these invasive plants, Ageratina adenophora ( Eupatorium adeophorum ), Chromolaena odorata ( Eupatorium odoratum ), and Tithonia diversifolia are severely imperiling this region. The structure and functions of ecosystems in this region are badly destroyed with the consequences that, the native species are in the face of extinction, and thai agricultural producers, animal husbandry, and forestry activities or even the ecological security are in danger. The damage of alien invasive plants in this region led to a great attention in our country. It is of great practical significance and scientific value to make a comprehensive study of the alien invasive plants of this region, to discover their principles of activity, to slow down their imperiling speed, to wipe out them from this region, and eventually to restore the ecological equilibrium. This paper gives a detailed description of the impacts of the alien invasive plants on the plants species diversity, plants community diversity, ecosystem diversity, agricultural producers, animal husbandry, and forestry. In the end, the authors suggested several solutions to control and wipe out the alien invasive plants.%论述中国西南纵向岭谷区外来入侵植物对生物多样性的影响.中国西南纵向岭谷区是我国生物多样性保护的关键地区.目前,该区域已成为外来植物入侵的重灾区,外来入侵植物种类多达70余种,其中,紫茎泽兰Ageratina adenophora(Eupatorium adenophorum)、飞机草Chromolaena odorata(Eupatorium odoratum)和肿柄菊Tithonia diversifolia等在该区域危害严重,该区域的生态系统的结构与功能遭

  1. 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.

  2. The alien paradox.

    OpenAIRE

    Tugby, Matthew

    2015-01-01

    Platonism delivers a theory of possibility that is distinct from both Lewisian modal realism and ersatz modal theories. By putting the topic of alien properties at centre stage in our modal theorizing, a strong preliminary case for platonism can be made. A puzzle about alien properties is created by modern truthmaker theory and some plausible assumptions about properties and existence. But this puzzle is one that platonism is able to solve in a simple and conservative way.

  3. Aliens in Paradise. Boat density and exotic coastal mollusks in Moorea Island (French Polynesia).

    Science.gov (United States)

    Ardura, Alba; Planes, Serge; Garcia-Vazquez, Eva

    2015-12-01

    Pacific islands are particularly vulnerable to the effects of invasive species. After habitat destruction or modification, invasive species are responsible for more biological extinctions than any other cause. Further, the rate of extinction of native species has been higher on islands than anywhere else in the world. Invasive species have also degraded native ecosystems. In order to detect exotic intertidal mollusk species, an extensive sampling around Moorea Island, a more or less unspoiled island surrounded by a rich coral reef habitat, has been developed considering that sampled points have different characteristics in wave exposure, algae coverage, type of substrate, distance to ports, distance to freshwater, distance sewage and boat traffic. Samples were DNA barcoded for unequivocal species assignation. The presence of five NIS among 26 species seems an important signal of introduction of alien biota in Moorea Island coast. However they were represented by a total of 38 individuals among 1487 mollusks (2.55%). While the distance to relatively big ports influenced directly species richness, the intensity of maritime traffic measured as boat density near sampling points was significantly associated with the frequency of exotic species. Other environmental factors did not show significant correlation with the frequency of exotics, suggesting that in an environment without big discontinuities, with little habitat modification, local boat traffic is the most influential factor in the spread of exotic species. This could be mitigated relatively easily by reducing boat density in local zones of ecological interest. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Red swamp crayfish: biology, ecology and invasion - an overview

    Directory of Open Access Journals (Sweden)

    Tainã Gonçalves Loureiro

    Full Text Available ABSTRACTAlien species have been transported and traded by humans for many centuries. However, with the era of globalization, biological invasions have reached notable magnitudes. Currently, introduction of alien species is one of the major threats to biodiversity and ecosystem functioning. The North American crayfish Procambarus clarkii is one of the most widely introduced freshwater species in the world, especially due to its high economic importance. It is responsible for great modifications in invaded environments causing irreparable ecological and economic damages. Its impressive ability to successfully colonize a wide range of environments is a consequence of its behavioural and biological characteristics that can adapt to features of the invaded location, conferring to this species a notable ecological plasticity. This review summarizes the available information regarding P. clarkii's biology and invasive dynamics around the world in order to contribute to the understanding of the threats posed by its establishment, as well as to support management and impact mitigation efforts.

  5. Ecological state of invasive alien plant Solanum rostratum in Beijing%北京外来入侵植物刺萼龙葵的生态状况

    Institute of Scientific and Technical Information of China (English)

    向俊; 李翠妮; 刘全儒; 周云龙; 孙乐; 毛春明; 梁前进

    2011-01-01

    Field investigation was made on ninety 2 m × 2 m sampling quadrats in Ligezhuang and Xiaocaocun villages of Miyun County, Beijing to analyze the population abundance, frequency, and importance value of invasive alien Solanum rostratum , as well as the species composition and flora characteristics of plant communities, aimed to assess the ecological state and ecological endangering risk of the invasive species based on its growth pattern, ecological advantage, and competitive aspects. In abundance, the S. rostratum was at the third position in Ligezhuang village (a total of 29 plant species) , and at the fifth position in Xiaocaocun village (a total of 51 plant species) ; in frequency, the S. ro.stratum was at the first position both in Ligezhuang and in Xiaocaocun. The importance value indicated that the S. rostratum both in Ligezhuang and in Xiaocaocun had the greatest comprehensive adaptability. Accordingly, the invasion of S. rostratum in Beijing was still at a stage at which the damage was limited and locally, though the plant had overcome its growth bottleneck. Several species belonged to Poaceae, Compositae, and Moraceae had the potential acting as a counterweight to the progressive expansion of S. rostratum. For ecological intervention strategy, it could be established in the native species with some advantages and somehow predominated in adaptation to ecologically substitute or eradicate the invasion of S. rostratum before it became a single dominant species.%调查了北京密云县李各庄和小漕村荒草地90个2 m×2 m草本优势型样方的刺萼龙葵入侵地,分析了样方中各种植物的种类组成和区系特点以及种群的多度、频度和重要值,并结合其生长型、生态优势和竞争关系,评估了北京外来入侵植物刺萼龙葵的生态状况和生态危害风险.结果表明:在多度方面,刺萼龙葵在李各庄群落(共29种植物)中位列第3,在小漕村群落(共51种植物)中位列第5;在频度方面,

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

    Directory of Open Access Journals (Sweden)

    Mmoto L. Masubelele

    2009-01-01

    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.

  7. [Application of molecular marker techniques in invasion ecology].

    Science.gov (United States)

    Chu, Dong; Zhang, You-jun; Wan, Fang-hao

    2007-06-01

    Alien invasive species can cause huge economic loss in agricultural and forestry production, and threaten biodiversity and human health. The research of invasion ecology is of significance in understanding the invasion mechanisms of alien invasive species and in developing corresponding sustainable control methods. Molecular marker is regarded as a useful tool in approaching some essential issues in the research of invasion ecology. In this paper, the applications of molecular marker techniques in the studies of identification, geographic distribution, invasive source, spread pattern, genetic variation, hybridization, and gene introgression of alien invasive species were reviewed, and the application prospects were discussed.

  8. Low Genetic Diversity and High Invasion Success of Corbicula fluminea (Bivalvia, Corbiculidae (Muller, 1774 in Portugal.

    Directory of Open Access Journals (Sweden)

    Cidália Gomes

    Full Text Available The Asian clam, Corbicula fluminea, is an invasive alien species (IAS originally from Asia that has spread worldwide causing major ecological and economic impacts in aquatic ecosystems. Here, we evaluated C. fluminea genetic (using COI mtDNA, CYTb mtDNA and 18S rDNA gene markers, morphometric and sperm morphology variation in Portuguese freshwater ecosystems. The COI marker revealed a single haplotype, which belongs to the Asian FW5 invasive lineage, suggesting a common origin for all the 13 Portuguese C. fluminea populations analysed. Morphometric analyses showed differences between the populations colonizing the North (with the exception of the Lima River and the Centre/South ecosystems. The sperm morphology examination revealed the presence of biflagellate sperm, a distinctive character of the invasive androgenetic lineages. The low genetic variability of the Portuguese C. fluminea populations and the pattern of sperm morphology have been illuminating for understanding the demographic history of this invasive species. We hypothesize that these populations were derived from a unique introductory event of a Corbicula fluminea FW5 invasive androgenic lineage in the Tejo River, which subsequently dispersed to other Portuguese freshwater ecosystems. The C. fluminea asexual reproductive mode may have assisted these populations to become highly invasive despite the low genetic diversity.

  9. The occurrence of alien plant species in field margins in Finland

    OpenAIRE

    Jauni, Miia; Hyvönen, Terho

    2009-01-01

    The results suggest that alien plant species comprise an important part of the biodiversity of Finnish field margins and semi-natural agricultural habitats. The role of field margins as dispersal corridors for invasive alien plants is limited for certain species.

  10. 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...

  11. The biological invasion in Albania

    OpenAIRE

    JULIAN SHEHU; ALMA IMERI; LIRIKA KUPE; ALFRED MULLAJ

    2014-01-01

    Albania, whose territory comprises many types of habitats and is characterized by a rich biological diversity, is particularly vulnerable to the threats posed by alien invasive species. The spread of invasive alien species is creating complex and far-reaching challenges that threaten both the natural biological riches of the earth and the well-being of our people. While the problem is global, the nature and severity of the impacts on society, economic life, health, and natural heritage are di...

  12. Review of alien marine macrophytes in Tunisia

    Directory of Open Access Journals (Sweden)

    Y. R. SGHAIER

    2014-06-01

    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.

  13. 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%.

  14. 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.

  15. Inventory of alien marine species of Cyprus (2009

    Directory of Open Access Journals (Sweden)

    S. KATSANEVAKIS

    2012-12-01

    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.

  16. Footprints of alien technology

    Science.gov (United States)

    Davies, P. C. W.

    2012-04-01

    If alien civilizations do, or did, exist, their technology will impact their environment. Some consideration has been given to the detection of large-scale astro-engineering, such as Dyson spheres. However, a very advanced technology might leave more subtle footprints requiring sophisticated scientific methods to uncover. We must not overlook the possibility that alien technology has impacted our immediate astronomical environment, even Earth itself, but probably a very long time ago. This raises the question of what traces, if anything, might remain today. I shall consider the possibilities of biological, geological and physical traces, and suggest ways that we might search for them.

  17. Alien Plant Invasion Situation in “Two Lakes and One Reservoir” Ecological Functional Area of Guiyang and Prevention Measures%贵阳市两湖一库生态功能区植物入侵情况及防范措施

    Institute of Scientific and Technical Information of China (English)

    石登红; 李灿

    2011-01-01

    为了解贵阳市外来入侵生物情况,对红枫湖、百花湖和阿哈水库的主要入侵植物进行了调查.结果表明:贵阳市红枫湖、百花湖和阿哈水库生态功能区外来入侵植物有52种,隶属于20科.入侵种以菊科最多,为15种;其次是苋科和豆科,分别为4种和6种.有28种入侵种来源于美洲,其他种来源于欧洲、亚洲、非洲等地区.有入侵行为的39种外来植物大部分属于田间杂草.并针对入侵植物的种类组成、入侵途径及危害程度等提出了相应的防范措施.%Results from investigation of alien invasive plants in “two lakes and one reservoir” ecological functional area of Guiyang showed that there were 51 plant species belonging to 20 families in the area, 15,4,and 6 species of which belonged to Compositae,Amarantaceae and Leguminosae,respectively. 28 species of them originated from America and others from Europe,Asia and Africa. Most of the 39 alien plants were field weeds. The prevention measures were proposed aiming at the composition, invading way and extent of injury of alien invasive plants.

  18. 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)

  19. Prediction of potential invasion range of alien plant Peperomia pellucida in China%外来入侵植物草胡椒在我国的潜分布范围预测

    Institute of Scientific and Technical Information of China (English)

    董旭; 陈秀芝; 娄玉霞; 郭水良

    2013-01-01

    Summary In recent years,new alien plants have constantly been invading China as a result of an increase of foreign exchanges.Peperomia pellucida (L.) Kunth,a species that originated from tropical America,is one of the alien species recently found in Shanghai.Its potential geographical distribution range and habitats of the species are still unknown.Scientists have applied a variety of ecological niche models to predict the risk of exotic plant invasions in China.Among these ecological niche models,maximum entropy (MaxEnt) model has higher accuracy of predicted results with small sample size. According to 12 environmental variables from the global climate environment database (http://www. worldclim.org/) and 649 occurrence records of P.pellucida in the world from the global biodiversity database (http://data.gbif.org/welcome.htm) and the Chinese Virtual Herbarium (http://www.cvh.org.cn/cms/),a prediction of P.pellucida potential distribution was conducted using MaxEnt model and ArcGis 9.3 software.In this prediction,12 environmental variables were used,including precipitation of wettest month,mean diurnal temperature range,isothermality,precipitation of warmest quarter,mean temperature of coldest quarter,variance in precipitation seasonality,precipitation of coldest quarter,temperature annual range,altitude,precipitation of driest month,mean temperature of warmest quarter,and mean temperature of driest quarter.When modeling,the occurrence data and environmental variables were firstly imported into the MaxEnt,and 75% of the occurrence data to predict the risk(training data)and the other(testing data)to test the accuracy were used.The raster layer of P.pellucida was gotten in the global potential distribution in ASCII format,then was imported into ArcGis for further analyses,and the potential suitable areas of P.pellucida in China was gotten.Finally,the result was confirmed by the ROC(receiver operating characteristics) curve analytical method,and the AUC(area under

  20. 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...... native rulers, and that the ability to punish does not allow alien rulers to “catch-up” with native rulers....

  1. The Origins of Alienation

    Science.gov (United States)

    Bronfenbrenner, Urie

    1974-01-01

    Evolutionary changes in the structure of the American family have led to an increase in the estrangement between young people and adults in the United States. The role of day care services, peer groups, schools, the community, and the organization of work are discussed in terms of their contribution to this alienation as well as possible changes…

  2. Alien Life Imagined

    Science.gov (United States)

    Brake, Mark

    2012-11-01

    1. Kosmos: aliens in ancient Greece; 2. The world turned upside down: Copernicanism and the voyages of discovery; 3. In Newton's train: pluralism and the system of the world; 4. Extraterrestrials in the early machine age; 5. After Darwin: the war of the worlds; 6. Einstein's sky: life in the new universe; 7. Ever since SETI: astrobiology in the space age; References; Index.

  3. Freshwater fish of the Wilderness National Park

    Directory of Open Access Journals (Sweden)

    I.A. Russell

    1999-01-01

    Full Text Available The study aimed to determine the distribution and relative abundance of freshwater fish in the Wilderness National Park. Fish assemblages in the Touw and Duiwe rivers were sampled in 1997 and 1998, with a total of 327 fish from nine species recorded. Indigenous species included two freshwater species (Pseudobarbus afer, Sandelia capensis, two catadromous species (Anguilla mossambicus, Myxus capensis, and two estuarine species (Monodactylusfalciformis, Caffrogobius multifasciatus. Three of the nine recorded species were alien (Micropterus dolomieu, Micropterus salmoides, Gambusia affinis, with the Micropterus spp., in particular, likely to have a substantial negative influence on indigenous species. A further one indigenous species, two translocated indigenous species, and five estuarine species could potentially be recorded in these rivers. River catchment management actions to restore perennial flow to the Duiwe River, to prevent the attenuation of floods, and to prevent further establishment and spread of alien and translocated biota are required to conserve indigenous fish assemblages.

  4. Freshwater fishes of Bontebok National Park

    Directory of Open Access Journals (Sweden)

    I.A. Russell

    2001-08-01

    Full Text Available Fish assemblages were sampled at six sites in the Breede River in the Bontebok National Park during 1999 and 2000. A total of 380 fish from 12 species was recorded. Indigenous fish collected included one freshwater species (Barbus andrewi, two catodromous species (Anguilla mossambica, Myxus capensis. and three estuarine species (Gilchris- tella aestuaria, Monodactylusfalciformis, Mugil cephalus. Four of the species recorded were aliens (Tinea tinea, Lepomis macrochirus, Micropterus salmoides, Micropterus dolomieu and two species translocated from other South African rivers (Tilapia sparrmanii, Clarias gariepinus. A further two indigenous species (Sandelia capensis, Pseudobarbus biirchelli could potentially occur within the park, though the high abundance of alien predators means that there is little chance for recolonisation from tributaries higher in the Breede River system. There is little opportunity to meaningfully conserve most indigenous freshwater fish in Bontebok National Park.

  5. 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.

  6. 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.

  7. Field and model investigations of freshwater lenses in coastal aquifers

    NARCIS (Netherlands)

    Pauw, P.S.

    2015-01-01

    A major problem of sustaining freshwater supply from freshwater lens is the invasion of saline groundwater into a fresh groundwater body. In many coastal areas saltwater intrusion has led to well closure and reduced freshwater supply. Furthermore, in the future saltwater intrusion is expected to inc

  8. The cobblers stick to their lasts : pollinators prefer native over alien plant species in a multi-species experiment

    OpenAIRE

    Chrobock, Thomas; Winiger, Pius; Fischer, Markus; van Kleunen, Mark

    2013-01-01

    The majority of plant species rely, at least partly, on animals for pollination. Our knowledge on whether pollinator visitation differs between native and alien plant species, and between invasive and non-invasive alien species is still limited. Additionally, because numerous invasive plant species are escapees from horticulture, the transition from human-assisted occurrence in urbanized habitats to unassisted persistence and spread in (semi-)natural habitats requires study. To address whethe...

  9. Low Genetic Diversity and High Invasion Success of Corbicula fluminea (Bivalvia, Corbiculidae) (Müller, 1774) in Portugal

    Science.gov (United States)

    Gomes, Cidália; Sousa, Ronaldo; Mendes, Tito; Borges, Rui; Vilares, Pedro; Vasconcelos, Vitor; Guilhermino, Lúcia; Antunes, Agostinho

    2016-01-01

    The Asian clam, Corbicula fluminea, is an invasive alien species (IAS) originally from Asia that has spread worldwide causing major ecological and economic impacts in aquatic ecosystems. Here, we evaluated C. fluminea genetic (using COI mtDNA, CYTb mtDNA and 18S rDNA gene markers), morphometric and sperm morphology variation in Portuguese freshwater ecosystems. The COI marker revealed a single haplotype, which belongs to the Asian FW5 invasive lineage, suggesting a common origin for all the 13 Portuguese C. fluminea populations analysed. Morphometric analyses showed differences between the populations colonizing the North (with the exception of the Lima River) and the Centre/South ecosystems. The sperm morphology examination revealed the presence of biflagellate sperm, a distinctive character of the invasive androgenetic lineages. The low genetic variability of the Portuguese C. fluminea populations and the pattern of sperm morphology have been illuminating for understanding the demographic history of this invasive species. We hypothesize that these populations were derived from a unique introductory event of a Corbicula fluminea FW5 invasive androgenic lineage in the Tejo River, which subsequently dispersed to other Portuguese freshwater ecosystems. The C. fluminea asexual reproductive mode may have assisted these populations to become highly invasive despite the low genetic diversity. PMID:27391333

  10. The biological invasion in Albania

    Directory of Open Access Journals (Sweden)

    JULIAN SHEHU

    2014-06-01

    Full Text Available Albania, whose territory comprises many types of habitats and is characterized by a rich biological diversity, is particularly vulnerable to the threats posed by alien invasive species. The spread of invasive alien species is creating complex and far-reaching challenges that threaten both the natural biological riches of the earth and the well-being of our people. While the problem is global, the nature and severity of the impacts on society, economic life, health, and natural heritage are distributed unevenly across nations and regions. Some aspects of the global invasive alien species (IAS problem require solutions tailored to the specific values, needs, and priorities of nations while others call for consolidated action by the larger world community. Preventing the international movement of invasive alien species and coordinating a timely and effective response to invasions requires cooperation and collaboration among governments, economic sectors, non-governmental organizations, and international treaty organizations. Many features have been attributed to invasive species and invaded ecosystems, but none are universal and invasive species tend to have a suite of traits rather than all of themThe large numbers of alien organisms introduced into Albania do not generally endanger the biodiversity on a large scale.

  11. Variation in the strength of reproductive interference from an alien congener to a native species in Taraxacum.

    Science.gov (United States)

    Nishida, Sachiko; Hashimoto, Keisuke; Kanaoka, Masahiro M; Takakura, Ko-Ichi; Nishida, Takayoshi

    2017-01-01

    Reproductive interference (RI) may be a contributing factor to the displacement of native species by an alien congener, and RI strength has been shown theoretically to affect distributional relationships between species. Thus, variations in RI strength from alien to native species result in different consequences of invasions and efforts to conserve native species, but the variations have seldom been examined empirically. We therefore investigated RI strength variations from the alien species Taraxacum officinale and its hybrids to eight populations of native dandelions, four T. japonicum populations and two populations each of two subspecies of T. platycarpum. We examined the association between alien relative abundance and native seed set in field surveys, and we also performed hand-pollination experiments to investigate directly the sensitivity of native flowers to alien pollen. We found that the effect of alien relative abundance on native seed set of even the same native species could differ greatly in different regions, and that the sensitivity of native flowers to alien pollen was also dependent on region. Our results, together with those of previous studies, show that RI from the alien to the native species is strong in regions where the alien species outnumbers the native species and marginal where it does not; this result suggests that alien RI can critically affect distributional relationships between native and alien species. Our study highlights the importance of performing additional empirical investigations of RI strength variation and of giving due attention to alien RI in efforts to conserve regional native biodiversity.

  12. 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

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. Optimising invasive fish management in the context of invasive species legislation in South Africa

    Directory of Open Access Journals (Sweden)

    Darragh J. Woodford

    2017-03-01

    Full Text Available Background: South Africa hosts a large number of non-native freshwater fishes that were introduced for various industries. Many of these species are now listed under the National Environmental Management: Biodiversity Act (NEM:BA Alien and Invasive Species (A&IS lists and regulations, though the practical options available to conservation agencies to effectively manage these fishes vary greatly among species and regions. Objectives & methods: We assessed the history and status of national legislation pertaining to invasive freshwater fishes, and the practical implications of the legislation for managing different species with contrasting distributions, impacts and utilisation value. Results: The smallmouth bass, despite being a potential conflict-generating species, is fairly straightforward to manage based on current legislation. Two species of trout, which remain absent from the NEM:BA A&IS lists because of ongoing consultation with stakeholders, continue to be managed in regions like the Western Cape province using existing provincial legislation. To maximise the limited capacity for management within conservation agencies, we proposed a decision-support tool that prioritises invasive fish populations that represent high environmental risk and low potential for conflict with stakeholders. Using three case studies, we demonstrated how the tool can be used to set management goals of ‘eradicate’, ‘manage against impacts and further spread’ and ‘continue to monitor population’ as the most pragmatic solutions given the state of an invasion, its socio-economic impact and the capacity of the responsible agency to act. Conclusion: By choosing a pragmatic management strategy, conservation agencies can maximise the effective deployment of limited resources, while minimising avoidable conflicts with stakeholders.

  20. A Letter to Alien

    Institute of Scientific and Technical Information of China (English)

    邱政榜

    2012-01-01

    Dear Alien, 1 am sorry to hear that you have some problems. I hear you argued with your best friend. 1 think you could call him up or go to his home. You could write him a letter. And you could tell him you are sony. Or maybe you could give him a ticket to a ball game. I am sure you will get on well with him again.

  1. The alien hand syndrome

    Science.gov (United States)

    Panikkath, Deepa; Mojumder, Deb; Nugent, Kenneth

    2014-01-01

    A 77-year-old woman presented with the complaint of observing her left hand moving without her knowledge while watching television. Her left hand stroked her face and hair as if somebody was controlling it. These movements lasted only half an hour but on recovery, she had left hemiparesis. Alien hand syndrome as the presentation of cardioembolic stroke is extremely rare but can be terrifying to patients. PMID:24982566

  2. Alien Introgression in Wheat

    OpenAIRE

    Molnár-Láng, M.; Ceoloni, C; Doležel, J

    2015-01-01

    This book provides an overview of the latest advancements in the field of alien introgression in wheat. The discovery and wide application of molecular genetic techniques including molecular markers, in situ hybridization, and genomics has led to a surge in interspecific and intergeneric hybridization in recent decades. The work begins with the taxonomy of cereals, especially of those species which are potential gene sources for wheat improvement. The text then goes on to cover.

  3. 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.

  4. Invasion and spreading of Cabomba caroliniana revealed by RAPD markers

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Applying randomly amplified polymorphic DNA (RAPD), the genetic variation of Cabomba caroliniana Gray (cabomba or fanwort), a new alien plant in China, was analyzed in this paper. Total 143 bands, including 47 polymorphic bands, were amplified from 23 primers in 20 samples. The sampling distance was large,but its genetic diversity was low. The main results were that: (1) Cabomba, which grew and dispersed mainly in fragment, was an abundant and dominant species in freshwater, and its main dispersal mechanism was vegetative reproduction. (2) Cabomba was originally introduced into China as an aquarium submerged plant. Somehow,those discarded cabomba became invasive species in the areas of Hangzhou, Shanghai, and Meicheng, and other places. (3) Although the level of genetic diversity in cabomba was low, their rapid dispersion and propagation could seriously harm to local aquatic community. Therefore, specific measure should be used to control cabomba from uncontrolled spreading and damage to local vegetation communities.

  5. Considerations of Building up a Supervision and Management System for Prevention and Control of Invasive Alien Species Posing Environmental Hazards in China%关于构建我国外来入侵物种环境危害防控监督管理体系的思考

    Institute of Scientific and Technical Information of China (English)

    丁晖; 马方舟; 吴军; 雷军成; 乐志芳; 徐海根

    2015-01-01

    外来入侵物种是造成全球生物多样性丧失的主要威胁因素,我国是世界上受外来入侵物种危害最严重的国家之一。近年来,我国外来入侵物种的发生态势出现重大变化,呈现出许多新特点,但现行管理制度不健全,管理策略不完善,技术支撑薄弱,管理能力不强。要建立以环境危害防控为目标的管理体系,形成“引进—建立种群—传播扩散—发生危害”过程中的“无缝”监管,提高防控措施的技术水平和综合运用能力。研究提出了与此相适应的管理框架、管理目标、管理范围、管理对象、基本原则、主要制度和措施,初步形成了我国外来入侵物种环境危害防控监督管理体系的构建方案。%Invasive alien species are major threats to biodiversity at the global level. China is among the countries most af⁃fected by invasive alien species. Especially in recent years, the situation has changed greatly, displaying a number of new characteristics. In coping with the changing situation, it is found that the governance system is incomplete, management strategy imperfect, technological support inadequate and management capacity insufficient in the country. It is, therefore, essential and critical to build up an environment⁃hazard⁃control⁃oriented holistic governance system, a“seamless” supervi⁃sion network over the entire process of“introduction⁃population⁃establishment⁃dissimilation and proliferation⁃hazard forma⁃tion”, and a set of control measures high in technical level and comprehensive applicability. To address the issue, a holis⁃tic governance system is brought forth, that including framework, targets, scope, objects, fundamental principles, main institutions and measures, which tentatively form a program for building up a supervision and management system for pre⁃vention and control of invasive alien species posing environmental hazards.

  6. Floristic analysis and distribution pattern of alien plants in Shandong Province,eastern China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Alien plants,along with their ecological invasion and negative impacts on indigenous species diversity and ecosystems,are one of the major topics of current ecological research.The background investigation and floristic analysis of alien plants are very important and form an essential database for invasive species research,control and management.In our study these alien plants,mainly collected from the Flora of Shandong Province,combined with a field survey,were studied and analyzed.We also established a floristic database.Our findings are as follows:1) there are a total of 827 alien species,belonging to 122 families and 416 genera of which 348 species were imported from other countries;2) a high proportion,39.0% of the flora in Shandong Province,is accounted for by alien species,of which 21 dominant families largely belong to the Rosaceae,Leguminosae,Asteraceae and Gramineae;3) the diverse geographical distribution of the genera is characterized by species dominant in the temperate zone which accounts for 52.5% of the alien plants and 44.1% of the plants from the tropics;4) the origins of alien species and their centralized distribution in Shandong together show the anthropogenic effect and unnatural impacts on the environment and 5) in Shandong Province,alien plants originate more from temperate zones than from any other areas of the world.

  7. Freshwater Wetlands.

    Science.gov (United States)

    Naturescope, 1986

    1986-01-01

    Provides descriptions about freshwater wetlands, such as marshes, swamps, and bogs. Contains three learning activities which deal with unusual wetland plants, the animals and plants in a typical marsh, and the effects of a draught on a swamp. Included are reproducible handouts and worksheets for two of the activities. (TW)

  8. Rapid proliferation of an endemic galaxiid following eradication of an alien piscivore (Perca fluviatilis) from a reservoir.

    Science.gov (United States)

    Beatty, S J; Morgan, D L

    2017-03-01

    Following the complete eradication of the alien piscivorous perch Perca fluviatilis from a potable reservoir, the abundance of the endemic western minnow Galaxias occidentalis, which was previously undetectable prior to the initial eradication event, increased dramatically. The study reveals the potential of reservoirs to act as ecological refuges and has implications for understanding the relative effects of alien fishes v. habitat alteration on native freshwater fishes.

  9. Aliens on Earth. Are reports of close encounters correct?

    CERN Document Server

    Sobkowicz, Pawel

    2012-01-01

    Popular culture (movies, SF literature) and witness accounts of close encounters with extraterrestrials provide a rather bizarre image of Aliens behavior on Earth. It is far from stereotypes of human space exploration. The reported Aliens are not missions of diplomats, scientists nor even invasion fleets; typical encounters are with lone ETs (or small groups), and involve curious behavior: abductions and experiments (often of sexual nature), cattle mutilations, localized killing and mixing in human society using various methods. Standard scientific explanations of these social memes point to influence of cultural artifacts (movies, literature) on social imagination, projection of our fears and observations of human society, and, in severe cases, psychic disorder of the involved individuals. In this work we propose an alternate explanation, claiming that the memes might be the result of observations of actual behavior of true Aliens, who, visiting Earth behave in a way that is then reproduced by such memes. Th...

  10. No saturation in the accumulation of alien species worldwide

    Science.gov (United States)

    Seebens, Hanno; Blackburn, Tim M.; Dyer, Ellie E.; Genovesi, Piero; Hulme, Philip E.; Jeschke, Jonathan M.; Pagad, Shyama; Pyšek, Petr; Winter, Marten; Arianoutsou, Margarita; Bacher, Sven; Blasius, Bernd; Brundu, Giuseppe; Capinha, César; Celesti-Grapow, Laura; Dawson, Wayne; Dullinger, Stefan; Fuentes, Nicol; Jäger, Heinke; Kartesz, John; Kenis, Marc; Kreft, Holger; Kühn, Ingolf; Lenzner, Bernd; Liebhold, Andrew; Mosena, Alexander; Moser, Dietmar; 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; van Kleunen, Mark; Walker, Kevin; Weigelt, Patrick; Yamanaka, Takehiko; Essl, Franz

    2017-01-01

    Although research on human-mediated exchanges of species has substantially intensified during the last centuries, we know surprisingly little about temporal dynamics of alien species accumulations across regions and taxa. Using a novel database of 45,813 first records of 16,926 established alien species, we show that the annual rate of first records worldwide has increased during the last 200 years, with 37% of all first records reported most recently (1970–2014). Inter-continental and inter-taxonomic variation can be largely attributed to the diaspora of European settlers in the nineteenth century and to the acceleration in trade in the twentieth century. For all taxonomic groups, the increase in numbers of alien species does not show any sign of saturation and most taxa even show increases in the rate of first records over time. This highlights that past efforts to mitigate invasions have not been effective enough to keep up with increasing globalization. PMID:28198420

  11. No saturation in the accumulation of alien species worldwide.

    Science.gov (United States)

    Seebens, Hanno; Blackburn, Tim M; Dyer, Ellie E; Genovesi, Piero; Hulme, Philip E; Jeschke, Jonathan M; Pagad, Shyama; Pyšek, Petr; Winter, Marten; Arianoutsou, Margarita; Bacher, Sven; Blasius, Bernd; Brundu, Giuseppe; Capinha, César; Celesti-Grapow, Laura; Dawson, Wayne; Dullinger, Stefan; Fuentes, Nicol; Jäger, Heinke; Kartesz, John; Kenis, Marc; Kreft, Holger; Kühn, Ingolf; Lenzner, Bernd; Liebhold, Andrew; Mosena, Alexander; Moser, Dietmar; 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; van Kleunen, Mark; Walker, Kevin; Weigelt, Patrick; Yamanaka, Takehiko; Essl, Franz

    2017-02-15

    Although research on human-mediated exchanges of species has substantially intensified during the last centuries, we know surprisingly little about temporal dynamics of alien species accumulations across regions and taxa. Using a novel database of 45,813 first records of 16,926 established alien species, we show that the annual rate of first records worldwide has increased during the last 200 years, with 37% of all first records reported most recently (1970-2014). Inter-continental and inter-taxonomic variation can be largely attributed to the diaspora of European settlers in the nineteenth century and to the acceleration in trade in the twentieth century. For all taxonomic groups, the increase in numbers of alien species does not show any sign of saturation and most taxa even show increases in the rate of first records over time. This highlights that past efforts to mitigate invasions have not been effective enough to keep up with increasing globalization.

  12. Environmental and economic impact of alien terrestrial arthropods in Europe

    Directory of Open Access Journals (Sweden)

    Sibylle Vaes-Petignat

    2014-06-01

    Full Text Available In the last decades abundance and importance of invasive alien species has grown continuously due to the undiminished growth of global trade. In most cases, arthropod introductions were unintended and occurred as hitchhikers or contaminants. Alien arthropods can have significant environmental impacts and can be economically costly. To measure these impacts, we expand the generic impact scoring system initially developed for mammals and birds, and applied it to terrestrial arthropods. The scoring of the 77 most widely distributed arthropod species alien to Europe revealed the mite Varroa destructor as the most harmful species, followed by the Chinese longhorn beetle Anoplophora chinensis and the Argentine ant Linepithema humile. The highest environmental impact is through herbivory, disease transmission, and ecosystem impacts. The highest economic impact is on agriculture and human infrastructure. The generic impact scoring system allows comparing impact scores of vertebrates and arthropods, thus serving as a background for decision making processes of policies and stakeholders.

  13. 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.

  14. 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.

  15. Insights into the evolution of freshwater sponges (Porifera: Demospongiae: Spongillina): Barcoding and phylogenetic data from Lake Tanganyika endemics indicate multiple invasions and unsettle existing taxonomy.

    Science.gov (United States)

    Erpenbeck, Dirk; Weier, Tina; de Voogd, Nicole J; Wörheide, Gert; Sutcliffe, Patricia; Todd, Jonathan A; Michel, Ellinor

    2011-10-01

    Sponges are a conspicuous element in many benthic habitats including in Africa's oldest, deepest lake, Lake Tanganyika. Despite their prevalence and pivotal ecological role as filter feeders, knowledge of the evolutionary history of sponges is in its infancy. Here, we provide the first molecular analysis targeting the evolution of sponges from Lake Tanganyika. Independent markers indicate the occurrence of several colonisation events which have shaped the current Tanganyikan lacustrine sponge biodiversity. This is in contrast to a range of previously studied organisms that have diversified within the lake from single lineages. Our tree reconstructions indicate the presence of two genera, Oncosclera and Eunapius, which are globally distributed. Therefore, we reject the hypothesis of monophyly for the sponges from Lake Tanganyika and challenge existing higher taxonomic structure for freshwater sponges.

  16. Global hotspots and correlates of alien species richness across taxonomic groups

    Science.gov (United States)

    Dawson, Wayne; Moser, Dietmar; van Kleunen, Mark; Kreft, Holger; Pergl, Jan; Pysek, Petr; Weigelt, Patrick; Winter, Marten; Lenzner, Bernd; Blackburn, Tim M.; Dyer, Ellie; Cassey, Phillip; Scrivens, Sally-Louise; Economo, Evan P.; Guenard, Benoit; Capinha, Cesar; Seebens, Hanno; Garcia-Diaz, Pablo; Nentwig, Wolfgang; Garcia-Berthou, Emili; Casal, Christine; Mandrak, Nicholas E.; Fuller, Pam; Meyer, Carsten; Essl, Franz

    2017-01-01

    Human-mediated transport beyond biogeographic barriers has led to the introduction and establishment of alien species in new regions worldwide. However, we lack a global picture of established alien species richness for multiple taxonomic groups. Here, we assess global patterns and potential drivers of established alien species richness across eight taxonomic groups (amphibians, ants, birds, freshwater fishes, mammals, vascular plants, reptiles and spiders) for 186 islands and 423 mainland regions. Hotspots of established alien species richness are predominantly island and coastal mainland regions. Regions with greater gross domestic product per capita, human population density, and area have higher established alien richness, with strongest effects emerging for islands. Ants and reptiles, birds and mammals, and vascular plants and spiders form pairs of taxonomic groups with the highest spatial congruence in established alien richness, but drivers explaining richness differ between the taxa in each pair. Across all taxonomic groups, our results highlight the need to prioritize prevention of further alien species introductions to island and coastal mainland regions globally.

  17. 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...

  18. 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

  19. 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.

  20. Wind dispersal of alien plant species into remnant natural vegetation from adjacent agricultural fields

    Directory of Open Access Journals (Sweden)

    Chika Egawa

    2017-07-01

    Full Text Available Knowledge regarding the seed dispersal of alien species is crucial to manage invasion risk in fragmented natural habitats. Focusing on wind dispersal, this study assessed the spatial and quantitative extents to which a remnant natural fen receives the seeds of alien species dispersed from adjacent hay meadows in Hokkaido, northern Japan. I established a total of 80 funnel seed traps in the fen at distances of 1, 2, 5, 10, 20, 30, 50, and 100 m from the meadows. The proportion of alien species in the seed rain at each distance was quantified, and the 99th-percentile dispersal distance from the meadows was estimated for each alien species by constructing dispersal kernels. Despite the presence of a marginal ditch and an elevational difference between the fen and the meadows, five alien species, including four grasses that do not have modified seed structures for wind dispersal, dispersed their seeds into the fen. These alien species accounted for up to 65.9% of the seed rain in terms of quantity. The 99th-percentile dispersal distances of the alien species ranged from 3.8 m to 309.3 m, and these distances were longer than the values predicted on the basis of their functional traits, such as terminal velocity. The results of this study demonstrated that numerous seeds of farmland-derived alien species were transported into the remnant vegetation via wind dispersal, and that simple predictions of dispersal distance based on functional traits could underestimate the potential area that alien species can reach. Continuous management both in farmland (to reduce seed escape and in remnant vegetation (to prevent the establishment of alien species is necessary to protect native vegetation from biological invasion in agricultural landscapes.

  1. 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...

  2. Structure design and establishment of database application system for alien species in Shandong Province, China

    Institute of Scientific and Technical Information of China (English)

    GUO Wei-hua; LIU Heng; DU Ning; ZHANG Xin-shi; WANG Ren-qing

    2007-01-01

    This paper presents a case study on structure design and establishment of database application system for alien species in Shandong Province, integrating with Geographic Information System, computer network, and database technology to the research of alien species. The modules of alien species database, including classified data input, statistics and analysis, species pictures and distribution maps,and out date input, were approached by Visual Studio.net 2003 and Microsoft SQL server 2000. The alien species information contains the information of classification, species distinction characteristics, biological characteristics, original area, distribution area, the entering fashion and route, invasion time, invasion reason, interaction with the endemic species, growth state, danger state and spatial information, i.e.distribution map. Based on the above bases, several models including application, checking, modifying, printing, adding and returning models were developed. Furthermore, through the establishment of index tables and index maps, we can also spatially query the data like picture,text and GIS map data. This research established the technological platform of sharing information about scientific resource of alien species in Shandong Province, offering the basis for the dynamic inquiry of alien species, the warning technology of prevention and the fast reaction system. The database application system possessed the principles of good practicability, friendly user interface and convenient usage. It can supply full and accurate information inquiry services of alien species for the users and provide functions of dynamically managing the database for the administrator.

  3. Contrasting biogeography of endemic and alien terrestrial species in the Canary Islands

    OpenAIRE

    Vilà, Montserrat

    2006-01-01

    Endemics and alien organisms can be considered two faces of the same coin, since management of both groups of taxa have strongly interrelated conservation implications. Islands are rich in endemic species and are also very vulnerable to biological invasions. We analysed the biogeography and taxonomy of endemic and alien terrestrial species in the Canary Islands including fungi, lichens, bryophytes, vascular plants, arthropods, molluscs, annelids and vertebrates. By using the plant dataset we ...

  4. Alien Hand Syndrome.

    Science.gov (United States)

    Hassan, Anhar; Josephs, Keith A

    2016-08-01

    Alien hand syndrome (AHS) is a rare disorder of involuntary limb movement together with a sense of loss of limb ownership. It most commonly affects the hand, but can occur in the leg. The anterior (frontal, callosal) and posterior variants are recognized, with distinguishing clinical features and anatomical lesions. Initial descriptions were attributed to stroke and neurosurgical operations, but neurodegenerative causes are now recognized as most common. Structural and functional imaging and clinical studies have implicated the supplementary motor area, pre-supplementary motor area, and their network connections in the frontal variant of AHS, and the inferior parietal lobule and connections in the posterior variant. Several theories are proposed to explain the pathophysiology. Herein, we review the literature to update advances in the understanding of the classification, pathophysiology, etiology, and treatment of AHS.

  5. Extirpation of freshwater mussels (Bivalvia: Unionidae) following the invasion of dreissenid mussels in an interconnecting river of the Laurentian Great Lakes

    Science.gov (United States)

    Schloesser, Don W.; Metcalfe-Smith, Janice L.; Kovalak, William P.; Longton, Gary D.; Smithee, Rick D.

    2006-01-01

    Previous (1992-1994) surveys for native freshwater mussels (Unionidae) along main channels of the Detroit River showed that unionids had been extirpated from all but four sites in the upper reaches of the river due to impacts of dreissenid mussels (Dreissena polymorpha and D. bugensis). These four sites were surveyed again in 1998 using the same sampling method (timed-random searches) to determine if they may serve as ''refugia'' where unionids and dreissenids co-exist. Two additional sites were sampled using additional methods (excavated-quadrat and line-transect searches) for comparison with unpublished data collected in 1987 and 1990. A total of four individuals of four species (Actinonaias ligamentina, Cyclonaias tuberculata, Lasmigona complanata and Pleurobema sintoxia) were found by timed-random searches at four sites in 1998 compared to 720 individuals of 24 species in 1992 and 39 individuals of 13 species in 1994. Excavated-quadrat and line-transect searches at the two additional sites yielded only one live specimen of Ptychobranchus fasciolaris compared to 288 individuals of 18 species in 1987 and 1990. Results of this study suggest that remaining densities of unionids in channels of the Detroit River are too low to support viable reproducing populations of any species. Therefore, we conclude that unionids have been extirpated from main channels of the Detroit River due to dreissenid infestation. As the Detroit River was one of the first water bodies in North America to be invaded by dreissenids, it is likely that unionids will also be extirpated from many other rivers and lakes across eastern North America over the next few decades. Resource agencies should be encouraged to implement active management programs to protect remaining unionid populations from zebra mussels.

  6. 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...

  7. AliEn Resource Brokers

    OpenAIRE

    Saiz, Pablo; Buncic, Predrag; Peters, Andreas J.

    2003-01-01

    AliEn (ALICE Environment) is a lightweight GRID framework developed by the Alice Collaboration. When the experiment starts running, it will collect data at a rate of approximately 2 PB per year, producing O(109) files per year. All these files, including all simulated events generated during the preparation phase of the experiment, must be accounted and reliably tracked in the GRID environment. The backbone of AliEn is a distributed file catalogue, which associates universal logical file name...

  8. 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.

  9. 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...

  10. Alien and endangered plants in the Brazilian Cerrado exhibit contrasting relationships with vegetation biomass and N : P stoichiometry.

    Science.gov (United States)

    Lannes, Luciola S; Bustamante, Mercedes M C; Edwards, Peter J; Venterink, Harry Olde

    2012-11-01

    Although endangered and alien invasive plants are commonly assumed to persist under different environmental conditions, surprisingly few studies have investigated whether this is the case. We examined how endangered and alien species are distributed in relation to community biomass and N : P ratio in the above-ground community biomass in savanna vegetation in the Brazilian Cerrado. For 60 plots, we related the occurrence of endangered (Red List) and alien invasive species to plant species richness, vegetation biomass and N : P ratio, and soil variables. Endangered plants occurred mainly in plots with relatively low above-ground biomass and high N : P ratios, whereas alien invasive species occurred in plots with intermediate to high biomass and low N : P ratios. Occurrences of endangered or alien plants were unrelated to extractable N and P concentrations in the soil. These contrasting distributions in the Cerrado imply that alien species only pose a threat to endangered species if they are able to invade sites occupied by these species and increase the above-ground biomass and/or decrease the N : P ratio of the vegetation. We found some evidence that alien species do increase above-ground community biomass in the Cerrado, but their possible effect on N : P stoichiometry requires further study.

  11. Comparing determinants of alien bird impacts across two continents: implications for risk assessment and management

    Science.gov (United States)

    Evans, Thomas; Kumschick, Sabrina; Dyer, Ellie; Blackburn, Tim

    2014-01-01

    Invasive alien species can have serious adverse impacts on both the environment and the economy. Being able to predict the impacts of an alien species could assist in preventing or reducing these impacts. This study aimed to establish whether there are any life history traits consistently correlated with the impacts of alien birds across two continents, Europe and Australia, as a first step toward identifying life history traits that may have the potential to be adopted as predictors of alien bird impacts. A recently established impact scoring system was used in combination with a literature review to allocate impact scores to alien bird species with self-sustaining populations in Australia. These scores were then tested for correlation with a series of life history traits. The results were compared to data from a previous study in Europe, undertaken using the same methodology, in order to establish whether there are any life history traits consistently correlated with impact across both continents. Habitat generalism was the only life history trait found to be consistently correlated with impact in both Europe and Australia. This trait shows promise as a potential predictor of alien bird impacts. The results support the findings of previous studies in this field, and could be used to inform decisions regarding the prevention and management of future invasions. PMID:25165531

  12. Stakeholder perceptions and practices regarding Prosopis (mesquite) invasions and management in South Africa

    National Research Council Canada - National Science Library

    Shackleton, Ross T; Le Maitre, David C; Richardson, David M

    2015-01-01

    Invasive alien trees impact the environment and human livelihoods. The human dimensions of such invasions are less well understood than the ecological aspects, and this is hindering the development of effective management strategies...

  13. Investigation and Study on the Alien Species in Aquaculture in the Lower Reaches of the Yangtze River

    Institute of Scientific and Technical Information of China (English)

    CHEN Jia-zhang; SHEN Gong-ming; MENG Shun-long; QU Jian-hong

    2011-01-01

    The lower reaches of the Yangze River is one of the central areas of freshwater shallow lakes in China and has the diverse climates with both warm temperate zone and sub-tropical zone,which makes it become one of the best areas for aquaculture,so nearly all of the aquaculture species from the world can live in the area.It is important for perfecting alien aquaculture species information data-base and environmental risk assessment system to investigate and study the aquaculture alien species in the lower reaches of the Yangze River.The results showed that the number of aquaculture alien species in the lower reaches of the Yangze River is 45 species,including 33 species of fishes,4 species of shellfish,7 species of crustaceans and 1 species of amphibian.Most of alien species are from America and the main transmitting way is intentional introducing.

  14. Records of alien marine species in the shallow coastal waters of Chios Island (2009

    Directory of Open Access Journals (Sweden)

    S. KATSANEVAKIS

    2012-12-01

    Full Text Available The shallow coastline of Chios Island was surveyed for the presence of any alien marine benthic species, during August 2009. Fourteen randomly selected sites were surveyed by snorkeling during standardized one-hour transects at depths between 0 and 10 m, and the presence of all identified alien benthic species was recorded. Six alien species were identified: Asparagopsis taxiformis, Caulerpa racemosa var. cylindracea, Stypopodium schimperi, Halophila stipulacea, Percnon gibbesi, and Siganus luridus. The green alga C. racemosa var. cylindracea was found in high densities in all the surveyed sites and was characterized as invasive in the island. The brown alga S. schimperi, the crab P. gibbesi, and the fish S. luridussustain established populations in the area. For three of the recorded marine alien species (S. schimperi, P. gibbesi, and S. luridus,Chios Island seems to be the northernmost margin of their geographical range in the Aegean Sea.

  15. 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...

  16. Evaluation of online information sources on alien species in Europe: the need of harmonization and integration.

    Science.gov (United States)

    Gatto, Francesca; Katsanevakis, Stelios; Vandekerkhove, Jochen; Zenetos, Argyro; Cardoso, Ana Cristina

    2013-06-01

    Europe is severely affected by alien invasions, which impact biodiversity, ecosystem services, economy, and human health. A large number of national, regional, and global online databases provide information on the distribution, pathways of introduction, and impacts of alien species. The sufficiency and efficiency of the current online information systems to assist the European policy on alien species was investigated by a comparative analysis of occurrence data across 43 online databases. Large differences among databases were found which are partially explained by variations in their taxonomical, environmental, and geographical scopes but also by the variable efforts for continuous updates and by inconsistencies on the definition of "alien" or "invasive" species. No single database covered all European environments, countries, and taxonomic groups. In many European countries national databases do not exist, which greatly affects the quality of reported information. To be operational and useful to scientists, managers, and policy makers, online information systems need to be regularly updated through continuous monitoring on a country or regional level. We propose the creation of a network of online interoperable web services through which information in distributed resources can be accessed, aggregated and then used for reporting and further analysis at different geographical and political scales, as an efficient approach to increase the accessibility of information. Harmonization, standardization, conformity on international standards for nomenclature, and agreement on common definitions of alien and invasive species are among the necessary prerequisites.

  17. Evaluation of Online Information Sources on Alien Species in Europe: The Need of Harmonization and Integration

    Science.gov (United States)

    Gatto, Francesca; Katsanevakis, Stelios; Vandekerkhove, Jochen; Zenetos, Argyro; Cardoso, Ana Cristina

    2013-06-01

    Europe is severely affected by alien invasions, which impact biodiversity, ecosystem services, economy, and human health. A large number of national, regional, and global online databases provide information on the distribution, pathways of introduction, and impacts of alien species. The sufficiency and efficiency of the current online information systems to assist the European policy on alien species was investigated by a comparative analysis of occurrence data across 43 online databases. Large differences among databases were found which are partially explained by variations in their taxonomical, environmental, and geographical scopes but also by the variable efforts for continuous updates and by inconsistencies on the definition of "alien" or "invasive" species. No single database covered all European environments, countries, and taxonomic groups. In many European countries national databases do not exist, which greatly affects the quality of reported information. To be operational and useful to scientists, managers, and policy makers, online information systems need to be regularly updated through continuous monitoring on a country or regional level. We propose the creation of a network of online interoperable web services through which information in distributed resources can be accessed, aggregated and then used for reporting and further analysis at different geographical and political scales, as an efficient approach to increase the accessibility of information. Harmonization, standardization, conformity on international standards for nomenclature, and agreement on common definitions of alien and invasive species are among the necessary prerequisites.

  18. 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...

  19. 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…

  20. Update of marine alien species in Hellenic waters

    Directory of Open Access Journals (Sweden)

    M.A. PANCUCCI-PAPADOPOULOU

    2012-12-01

    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.

  1. 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...

  2. How Do Alien Plants Fit in the Space-Phylogeny Matrix?

    Science.gov (United States)

    Procheş, Şerban; Forest, Félix; Jose, Sarah; De Dominicis, Michela; Ramdhani, Syd; Wiggill, Timothy

    2015-01-01

    Recent advances in the field of plant community phylogenetics and invasion phylogenetics are mostly based on plot-level data, which do not take into consideration the spatial arrangement of individual plants within the plot. Here we use within-plot plant coordinates to investigate the link between the physical distance separating plants, and their phylogenetic relatedness. We look at two vegetation types (forest and grassland, similar in species richness and in the proportion of alien invasive plants) in subtropical coastal KwaZulu-Natal, South Africa. The relationship between phylogenetic distance and physical distance is weak in grassland (characterised by higher plant densities and low phylogenetic diversity), and varies substantially in forest vegetation (variable plant density, higher phylogenetic diversity). There is no significant relationship between the proportion of alien plants in the plots and the strength of the physical-phylogenetic distance relationship, suggesting that alien plants are well integrated in the local spatial-phylogenetic landscape. PMID:25893962

  3. 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)

  4. Can we Communicate with Aliens?

    Science.gov (United States)

    Csányi, V.; Kampis, Gy.

    The subject of this paper is: what answer can be given if the aliens are neither animals nor humans of an unknown culture, but specimens of an extraterrestrial intelligence? If we generalize this question, we may ask, how and to what extent is communication possible among intelligent beings?

  5. Freshwater systems; Frisch gezapft

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J.P.

    2008-06-09

    Increasingly, providers of solar systems are also offering freshwater systems, although these are more costly than combined storage systems. The contribution discusses the pros and cons of these systems as well as the freshwater quality. (orig.)

  6. Does responsiveness to arbuscular mycorrhizas depend on plant invasive status?

    Science.gov (United States)

    1. Some posit invasive alien plants are less dependent on mycorrhizal associations than native plants, and thus weak mycorrhizal responsiveness may be a general mechanism of plant invasion. 2. Here, we tested whether mycorrhizal responsiveness varies by plant invasive status while controlling for ph...

  7. 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.

  8. 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. PMID:24465640

  9. A List of Alien Plants in the Kruger National Park

    Directory of Open Access Journals (Sweden)

    I.A.W. Macdonald

    1988-10-01

    Full Text Available The alien vascular plant flora of the Kruger National Park is listed. Annotations cover the invasive status, modes of introduction and dispersal, dates of first recording, ecological impacts and control status of each species. The list comprises 156 species of which 113 are considered invasive within the park. Most of the species have been accidentally introduced to the park. The ecological impacts of 27 species (of which 11 are trees and shrubs were rated as moderate or high. By 1985 only 10 species are thought to have been eradicated from the park. Most of the invasive species are herbaceous weeds of man-disturbed sites and the eradication of these is generally considered impossible. Most of the important species are dispersed by water and animals. The significance of limiting reinvasion of the park down the rivers flowing into the park, is stressed.

  10. 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...

  11. Optimal Resource Management in the Presence of a Deleterious Alien Species

    NARCIS (Netherlands)

    Batabyal, A.A.; Nijkamp, Peter

    2007-01-01

    Various plants and resources such as orchards are vulnerable to the detrimental effects of successful invasions by alien animal or plant species. To outline an appropriate policy response, we first use renewal theory to construct a stochastic model of optimal orchard management in the presence of a

  12. 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

  13. Optimal Resource Management in the Presence of a Deleterious Alien Species

    NARCIS (Netherlands)

    Batabyal, A.A.; Nijkamp, Peter

    2007-01-01

    Various plants and resources such as orchards are vulnerable to the detrimental effects of successful invasions by alien animal or plant species. To outline an appropriate policy response, we first use renewal theory to construct a stochastic model of optimal orchard management in the presence of a

  14. 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.

  15. Efficient distinction of invasive aquatic plant species from non-invasive related species using DNA barcoding

    NARCIS (Netherlands)

    Ghahramanzadeh, R.; Esselink, G.; Kodde, L.P.; Duistermaat, H.; Valkenburg, van J.L.C.H.; Marashi, S.H.; Smulders, M.J.M.; Wiel, van de C.C.M.

    2013-01-01

    Biological invasions are regarded as threats to global biodiversity. Among invasive aliens, a number of plant species belonging to the genera Myriophyllum, Ludwigia and Cabomba, and to the Hydrocharitaceae family pose a particular ecological threat to water bodies. Therefore, one would try to

  16. Efficient distinction of invasive aquatic plant species from non-invasive related species using DNA barcoding

    NARCIS (Netherlands)

    Ghahramanzadeh, R.; Esselink, G.; Kodde, L.P.; Duistermaat, H.; Valkenburg, van J.L.C.H.; Marashi, S.H.; Smulders, M.J.M.; Wiel, van de C.C.M.

    2013-01-01

    Biological invasions are regarded as threats to global biodiversity. Among invasive aliens, a number of plant species belonging to the genera Myriophyllum, Ludwigia and Cabomba, and to the Hydrocharitaceae family pose a particular ecological threat to water bodies. Therefore, one would try to preven

  17. 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

  18. 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

  19. 湿地外来植物香菇草(Hydrocotyle vulgaris)入侵风险研究%Study on invasion risk of Hydrocotyle vulgaris as an alien species in wetlands

    Institute of Scientific and Technical Information of China (English)

    缪丽华; 季梦成; 王莹莹; 乔东东; 陈煜初

    2011-01-01

    通过对香菇草(Hydrocotyle vulgaris)形态特征、生长习性以及繁殖特点的研究以揭示其入侵风险.结果表明:1)香菇草适应性强,具有表型可塑性,能适应水生到旱生、强光到隐蔽等多种生境,并具有较好的耐受性,从而能占据更宽的生态幅;2)侵占力强,能形成比较高密度的植株丛成片生长,地下部分由根茎和大量的不定根密集网状交错,在地上、地下高密度占领生境从而排挤其他植物,降低群落物种多样性;3)繁殖速度快,可营养繁殖和种子繁殖,以根茎营养繁殖为主,自然生长的香菇草个体1年繁殖倍数达到50倍以上;4)根除难度大,根茎的片断残留仍然可生长成新的植株再次快速繁殖扩大;5)根据香菇草的生长习性,其适生区域的气候特征指标为:日平均温度稳定≥10℃天数多于180 d,最冷月(1月)平均温度高于-5℃,年极端最低气温不低于-10℃;结合我国的气候数据,预测划分香菇草的适生范围包括:中国北亚热带湿润区、中亚热带湿润区、南亚热带湿润区、边缘热带湿润区、中热带湿润区、赤道热带湿润区和中国高原亚热带地区;6)采用外来物种入侵风险指数评估体系分析香菇草的入侵风险表明,其入侵风险指数可确定得分为71分,其中“繁殖和扩散特性”项目得39分.说明香菇草入侵风险程度极高,属于“不可引入物种”.最后提出了香菇草入侵风险管理建议.%The growth habit, morphological and reproductive characteristics of Hydrocotyle vulgaris were systematically described to assess its invasion risks. The results showed that the invasion risks of H. Vulgaris were displayed in four aspects. First, the adaptability and phenotypic plasticity of H. Vulgaris ensured its adaptation to the environment. Also its tolerance contributed to the occupation of wider ecological amplitude. Second, the aggressive ability made it able to occupy the habitat

  20. 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.

  1. Invading freshwater snails and biological control in Martinique Island, French West Indies

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Pointier

    2001-09-01

    Full Text Available Eight alien freshwater snail species were introduced into Martinique Island during the last 50 years. The introduced snails include four planorbids (Biomphalaria straminea, Helisoma duryi, Amerianna carinata and Gyraulus sp., three thiarids (Melanoides tuberculata, M. amabilis and Tarebia granifera and one ampullarid (Marisa cornuarietis. Four of these species rapidly colonized the whole Martinican hydrographic system whereas the other four remained restricted to some particular sites. The invasion processes were documented during the last 20 years and showed (i a rapid invasion of the island by several morphs of M. tuberculata at the beginning of the 80's; (ii the introduction of T. granifera in 1991 and M. amabilis in 1997; and (iii the rapid spread of these last two species throughout the island. In the years following its introduction, M. tuberculata was used in biological control experiments against the snail hosts of schistosomiasis, B. glabrata and B. straminea. Experiments were conducted with success in several groups of water-cress beds which constituted the latest transmission sites for schistosomiasis at the beginning of the 80's. A malacological survey carried out in 2000 all over the island showed the absence of B. glabrata but the presence of some residual populations of B. straminea. Long-term studies carried out in Martinique have shown that the thiarids are able to maintain relatively stable populations over a long period of time, thus preventing recolonization by the snail hosts. Within this context the invasion of the hydrographic system of Martinique by thiarid snails has resulted in an efficient and sustainable control of the intermediate hosts of schistosomiasis.

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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.

  7. Assessing the importance of alien macro-Crustacea (Malacostraca) within macroinvertebrate assemblages in Belgian coastal harbours

    Science.gov (United States)

    Boets, Pieter; Lock, Koen; Goethals, Peter L. M.

    2012-06-01

    Harbours, which are often characterised by anthropogenic stress in combination with intensive international ship traffic, tend to be very susceptible to aquatic invasions. Since alien macrocrustaceans are known to be very successful across many European waters, a study was made on their distribution and impact in the four Belgian coastal harbours (Nieuwpoort, Ostend, Blankenberge and Zeebrugge). Biological and physical-chemical data were gathered at 43 sampling sites distributed along a salinity gradient in the four harbours. One-fourth of all crustacean species recorded were alien and represented on average 30% of the total macrocrustacean abundance and 65% of the total macrocrustacean biomass. The large share of alien crustaceans in the total macrocrustacean biomass was mainly due to several large alien crab species. Most alien species were found in the oligohaline zone, whereas the number of indigenous species slightly increased with increasing salinity. The low number of indigenous species present at low salinities was probably not only caused by salinity, but also by the lower water quality in this salinity range. Based on the site-specific biocontamination index (SBCI), which was used to assess the ecological water quality, the harbour of Nieuwpoort and Ostend scored best and were classified as good, indicating the limited abundance and the low number of alien macrocrustaceans. Sampling locations situated more inland generally had a higher SBCI and a lower ecological water quality. Zeebrugge and Blankenberge were characterised by a severe biocontamination. For Zeebrugge, this is probably related to the intensive transcontinental commercial ship traffic, whereas for Blankenberge, this could be due to introduction of alien species via recreational crafts or due to its geographical location in the proximity of Zeebrugge. Consistent monitoring of estuarine regions and harbours, which are seen as hotspots for introductions, could help in understanding and

  8. AliEn Resource Brokers

    CERN Document Server

    Saiz, P; Peters, A J; Saiz, Pablo; Buncic, Predrag; Peters, Andreas J.

    2003-01-01

    AliEn (ALICE Environment) is a lightweight GRID framework developed by the Alice Collaboration. When the experiment starts running, it will collect data at a rate of approximately 2 PB per year, producing O(109) files per year. All these files, including all simulated events generated during the preparation phase of the experiment, must be accounted and reliably tracked in the GRID environment. The backbone of AliEn is a distributed file catalogue, which associates universal logical file name to physical file names for each dataset and provides transparent access to datasets independently of physical location. The file replication and transport is carried out under the control of the File Transport Broker. In addition, the file catalogue maintains information about every job running in the system. The jobs are distributed by the Job Resource Broker that is implemented using a simplified pull (as opposed to traditional push) architecture. This paper describes the Job and File Transport Resource Brokers and sho...

  9. Alien liquid detector and control

    Energy Technology Data Exchange (ETDEWEB)

    Potter, B.M.

    1980-09-02

    An alien liquid detector employs a monitoring element and an energizing circuit for maintaining the temperature of the monitoring element substantially above ambient temperature. For this purpose an electronic circit controls a flow of heating current to the monitoring element. The presence of an alien liquid is detected by sensing a predetermined change in heating current flow to the monitoring element, e.g., to distinguish between water and oil. In preferred embodiments the monitoring element is a thermistor whose resistance is compared with a reference resistance and heating current through the thermistor is controlled in accordance with the difference. In one embodiment a bridge circuit senses the resistance difference; the difference may be sensed by an operational amplifier arrangement. Features of the invention include positioning the monitoring element at the surface of water, slightly immersed, so that the power required to maintain the thermistor temperature substantially above ambient temperature serves to detect presence of oil pollution at the surface.

  10. 'Would you eat an alien?'

    Science.gov (United States)

    2016-12-10

    A novel way of exploring comparative cognition, animal welfare ethics and human-animal relations formed the basis of this year's Wooldridge Memorial Lecture, held during the BVA Congress at the London Vet Show last month. Christine Nicol, of the University of Bristol, shared her experiences of making the BBC Radio 4 series 'Would you eat an alien?' and gave an insight into the ethical dilemmas that formed the basis of the programme. Laura Honey reports.

  11. 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...

  12. 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...

  13. 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),...

  14. Alienation in educational organizations and its’ management

    Directory of Open Access Journals (Sweden)

    Pınar Sarpkaya

    2009-09-01

    Full Text Available The purpose of this study was to study the alienation in educational organizations carefully and to call attention to this subject which was studied insufficiently. Descriptive method was used in the study. The concept of alienation was brought up with philosophical and sociological principals and then common inferences about the educational organizations were made within the help of studies which were about the alienation in educational institutions. Hegel was the first to consider the fact of “alienation” philosophically in his book “Phenomenology of Spirit ”. To Hegel human history is also the history of human being’s becoming alienated to himself. After Hegel, Ludwig Feuerbach considered this fact in his book “Essence of Christianity” in 1841. According to Marx, alienation is a compulsory phase that development of human being must have. Marx emphasizes that in capitalist society which is named as modern society man with his labor in production relations becomes alienated to his labor, then to his social relationships, and finally to himself. In his opinion, man is desired to pull in to the consumption helical that is obstinately insisted as necessity. In this way, consumption and dissatisfaction are two elements which set off and product each other. Alienation is deterioration and decay conceit of human existence’s natural, social, psychological and cultural dimensions. It is human being’s separating from each other and becoming alienated to each other. In this respect, alienation means that man survives by becoming distant to himself, to the product he produces, to his natural, social, psychological and cultural environment but under the control of their dominance and decisiveness. Seeman distinguishes alienation into five; Powerlessness, Meaninglessness, Normlessness, Isolation and self-estrangement. The studies that are made in educational organizations about alienation focus on alienation of teacher and student. There

  15. Alienation in educational organizations and its’ management

    Directory of Open Access Journals (Sweden)

    Sadi Yılmaz

    2009-09-01

    Full Text Available The purpose of this study was to study the alienation in educational organizations carefully and to call attention to this subject which was studied insufficiently. Descriptive method was used in the study. The concept of alienation was brought up with philosophical and sociological principals and then common inferences about the educational organizations were made within the help of studies which were about the alienation in educational institutions. Hegel was the first to consider the fact of “alienation” philosophically in his book “Phenomenology of Spirit  ”. To Hegel human history is also the history of human being’s becoming alienated to himself. After Hegel, Ludwig Feuerbach considered this fact in his book “Essence of Christianity” in 1841. According to Marx, alienation is a compulsory phase that development of human being must have. Marx emphasizes that in capitalist society which is named as modern society man with his labor in production relations becomes alienated to his labor, then to his social relationships, and finally to himself. In his opinion, man is desired to pull in to the consumption helical that is obstinately insisted as necessity. In this way, consumption and dissatisfaction are two elements which set off and product each other. Alienation is deterioration and decay conceit of human existence’s natural, social, psychological and cultural dimensions. It is human being’s separating from each other and becoming alienated to each other. In this respect, alienation means that man survives by becoming distant to himself, to the product he produces, to his natural, social, psychological and cultural environment but under the control of their dominance and decisiveness. Seeman distinguishes alienation into five; Powerlessness, Meaninglessness, Normlessness, Isolation and self-estrangement. The studies that are made in educational organizations about alienation focus on alienation of teacher and student. There

  16. Invasive mutualists erode native pollination webs.

    Directory of Open Access Journals (Sweden)

    Marcelo A Aizen

    2008-02-01

    Full Text Available Plant-animal mutualisms are characterized by weak or asymmetric mutual dependences between interacting species, a feature that could increase community stability. If invasive species integrate into mutualistic webs, they may alter web structure, with consequences for species persistence. However, the effect of alien mutualists on the architecture of plant-pollinator webs remains largely unexplored. We analyzed the extent of mutual dependency between interacting species, as a measure of mutualism strength, and the connectivity of 10 paired plant-pollinator webs, eight from forests of the southern Andes and two from oceanic islands, with different incidences of alien species. Highly invaded webs exhibited weaker mutualism than less-invaded webs. This potential increase in network stability was the result of a disproportionate increase in the importance and participation of alien species in the most asymmetric interactions. The integration of alien mutualists did not alter overall network connectivity, but links were transferred from generalist native species to super-generalist alien species during invasion. Therefore, connectivity among native species declined in highly invaded webs. These modifications in the structure of pollination webs, due to dominance of alien mutualists, can leave many native species subject to novel ecological and evolutionary dynamics.

  17. 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.

  18. 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.

  19. Urban Power Line Corridors as Novel Habitats for Grassland and Alien Plant Species in South-Western Finland.

    Science.gov (United States)

    Lampinen, Jussi; Ruokolainen, Kalle; Huhta, Ari-Pekka

    2015-01-01

    Regularly managed electric power line corridors may provide habitats for both early-successional grassland plant species and disturbance-dependent alien plant species. These habitats are especially important in urban areas, where they can help conserve native grassland species and communities in urban greenspace. However, they can also provide further footholds for potentially invasive alien species that already characterize urban areas. In order to implement power line corridors into urban conservation, it is important to understand which environmental conditions in the corridors favor grassland species and which alien species. Likewise it is important to know whether similar environmental factors in the corridors control the species composition of the two groups. We conducted a vegetation study in a 43 kilometer long urban power line corridor network in south-western Finland, and used generalized linear models and distance-based redundancy analysis to determine which environmental factors best predict the occurrence and composition of grassland and alien plant species in the corridors. The results imply that old corridors on dry soils and steep slopes characterized by a history as open areas and pastures are especially suitable for grassland species. Corridors suitable for alien species, in turn, are characterized by productive soils and abundant light and are surrounded by a dense urban fabric. Factors controlling species composition in the two groups are somewhat correlated, with the most important factors including light abundance, soil moisture, soil calcium concentration and soil productivity. The results have implications for grassland conservation and invasive alien species control in urban areas.

  20. 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

    2013-04-01

    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.

  1. Feasting in fresh water: impacts of food concentration on freshwater tolerance and the evolution of food × salinity response during the expansion from saline into fresh water habitats.

    Science.gov (United States)

    Lee, Carol Eunmi; Moss, Wynne E; Olson, Nora; Chau, Kevin Fongching; Chang, Yu-Mei; Johnson, Kelsey E

    2013-06-01

    Saline to freshwater invasions have become increasingly common in recent years. A key hypothesis is that rates of freshwater invasions have been amplified in recent years by increased food concentration, yet this hypothesis has remained unexplored. We examined whether elevated food concentration could enhance freshwater tolerance, and whether this effect evolves following saline to freshwater invasions. We examined physiological response to salinity and food concentration in a 2 × 2 factorial design, using ancestral brackish and freshwater invading populations of the copepod Eurytemora affinis. We found that high food concentration significantly increases low-salinity tolerance. This effect was reduced in the freshwater population, indicating evolution following the freshwater invasion. Thus, ample food could enable freshwater invasions, allowing subsequent evolution of low-salinity tolerance even under food-poor conditions. We also compared effects of food concentration on freshwater survival between two brackish populations from the native range. Impacts of food concentration on freshwater survival differed between the brackish populations, suggesting variation in functional properties affecting their propensity to invade freshwater habitats. The key implication is that high food concentration could profoundly extend range expansions of brackishwater species into freshwater habitats, potentially allowing for condition-specific competition between saline invaders and resident freshwater species.

  2. 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.

  3. Invasive mechanism and control strategy of Ageratina adenophora (Sprengel)

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In order to ascertain the invasive mechanism and control strategy of the invasive Crofton weed, Ageratina adenophora, its ecological adaptability and population differentiation,the formation of single dominant population, displacement of native plants and sustainable management strategies were investigated. The present results helped to clarify and explain such issues as the adaptability post invasion,interaction and competition between inter-and intra-species and community resistance, thereby providing important references to researches on other invasive alien species.

  4. Alienation and the Four Worlds of Childhood.

    Science.gov (United States)

    Bronfenbrenner, Urie

    1986-01-01

    Outlines the four worlds of childhood and the ways that alienation in adolescents can be counteracted through the creation of interconnecting links. The risks of losing youths to alienating factors caused by institutions, the social structure, and the pressures under which schools and families function is the highest it has ever been. (MD)

  5. Alienation and the Four Worlds of Childhood.

    Science.gov (United States)

    Bronfenbrenner, Urie

    1986-01-01

    Outlines the four worlds of childhood and the ways that alienation in adolescents can be counteracted through the creation of interconnecting links. The risks of losing youths to alienating factors caused by institutions, the social structure, and the pressures under which schools and families function is the highest it has ever been. (MD)

  6. 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)

  7. 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…

  8. An updated review of alien species on the coasts of Turkey

    Directory of Open Access Journals (Sweden)

    M.E. CINAR

    2012-12-01

    Full Text Available This 2010 review of alien species along the coasts of Turkey represents a total of 400 alien species belonging to 14 systematic groups. The present paper also reports the first findings ofVanderhorstia mertensi in the Aegean Sea (Gökova Bay, Chama adspersa in the Sea of Marmara andMya arenaria in the Aegean Sea. A total of 124 new alien species was determined within the last 5 years. Mollusca had the highest number of species (105 species, followed by Polychaeta (75 species, Crustacea (64 species and Pisces (58 species. The highest number of alien species (330 species were encountered on the Levantine coast of Turkey, followed by the Aegean Sea (165 species, Sea of Marmara (69 species and Black Sea (20 species. The Suez Canal (66% of the total number of alien species is the main vector for species introductions to the coasts of Turkey, followed by the ship-mediated transport (30%. The majority of species (306 species, 76% of total number of species have become established in the area, while 59 species are classified as casual (15%, 23 species as questionable (6% and 13 species as cryptogenic (3%. One new alien species was introduced to the coasts of Turkey every 4 weeks between 1991 and 2010. The majority of aliens were found on soft substratum (198 species in shallow waters (0-10 m (319 species. Some species such asCaulerpa racemosa, Amphistegina lobifera, Amphisorus hemprichii, Rhopilema nomadica, Mnemiopsis leidyi, Hydroides spp., Ficopomatus enigmaticus, Charybdis longicollis, Rapana venosa, Asterias rubens, Siganus spp. and Lagocephalus sceleratus show high invasive characters, and have great impacts both on the prevailing ecosystems and humans.

  9. Alien Phytogeographic Regions of Southern Africa: Numerical Classification, Possible Drivers, and Regional Threats

    Science.gov (United States)

    Hugo, Sanet; Van Rensburg, Berndt J.; Van Wyk, Abraham E.; Steenkamp, Yolande

    2012-01-01

    The distributions of naturalised alien plant species that have invaded natural or semi-natural habitat are often geographically restricted by the environmental conditions in their new range, implying that alien species with similar environmental requirements and tolerances may form assemblages and characterise particular areas. The aim of this study was to use objective numerical techniques to reveal any possible alien phytogeographic regions (i.e. geographic areas with characteristic alien plant assemblages) in southern Africa. Quarter degree resolution presence records of naturalised alien plant species of South Africa, Lesotho, Swaziland, Namibia and Botswana were analysed through a divisive hierarchical classification technique, and the output was plotted on maps for further interpretation. The analyses revealed two main alien phytogeographic regions that could be subdivided into eight lower level phytogeographic regions. Along with knowledge of the environmental requirements of the characteristic species and supported by further statistical analyses, we hypothesised on the main drivers of alien phytogeographic regions, and suggest that environmental features such as climate and associated biomes were most important, followed by human activities that modify climatic and vegetation features, such as irrigation and agriculture. Most of the characteristic species are not currently well-known as invasive plant species, but many may have potential to become troublesome in the future. Considering the possibility of biotic homogenization, these findings have implications for predicting the characteristics of the plant assemblages of the future. However, the relatively low quality of the dataset necessitates further more in-depth studies with improved data before the findings could be directly beneficial for management. PMID:22574145

  10. An updated review of alien species on the coasts of Turkey

    Directory of Open Access Journals (Sweden)

    M.E. CINAR

    2011-05-01

    Full Text Available This 2010 review of alien species along the coasts of Turkey represents a total of 400 alien species belonging to 14 systematic groups. The present paper also reports the first findings ofVanderhorstia mertensi in the Aegean Sea (Gökova Bay, Chama adspersa in the Sea of Marmara andMya arenaria in the Aegean Sea. A total of 124 new alien species was determined within the last 5 years. Mollusca had the highest number of species (105 species, followed by Polychaeta (75 species, Crustacea (64 species and Pisces (58 species. The highest number of alien species (330 species were encountered on the Levantine coast of Turkey, followed by the Aegean Sea (165 species, Sea of Marmara (69 species and Black Sea (20 species. The Suez Canal (66% of the total number of alien species is the main vector for species introductions to the coasts of Turkey, followed by the ship-mediated transport (30%. The majority of species (306 species, 76% of total number of species have become established in the area, while 59 species are classified as casual (15%, 23 species as questionable (6% and 13 species as cryptogenic (3%. One new alien species was introduced to the coasts of Turkey every 4 weeks between 1991 and 2010. The majority of aliens were found on soft substratum (198 species in shallow waters (0-10 m (319 species. Some species such asCaulerpa racemosa, Amphistegina lobifera, Amphisorus hemprichii, Rhopilema nomadica, Mnemiopsis leidyi, Hydroides spp., Ficopomatus enigmaticus, Charybdis longicollis, Rapana venosa, Asterias rubens, Siganus spp. and Lagocephalus sceleratus show high invasive characters, and have great impacts both on the prevailing ecosystems and humans.

  11. Freshwater fishes of Golden Gate Highlands National Park

    Directory of Open Access Journals (Sweden)

    I.A. Russell

    2005-06-01

    Full Text Available The study aimed to determine the distribution and relative abundance of freshwater fishes in the Golden Gate Highlands National Park. A total of 1778 fish specimens from three species were collected during surveys carried out in the Little Caledon River during 2002. The chubbyhead barb Barbus anoplus was the only indigenous species recorded, and comprised 99.5 of the total catch. Two of the three recorded species were alien {Cypnnus carpio, Oncorhynchus mykiss}. A further nine indigenous species could potentially occur within the park, though are unlikely to be permanent residents. Barriers formed by instream impoundments may prevent temporary immigration of indigenous fishes, but also limit the further spread of alien species in the park's rivers.

  12. 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

  13. 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.

  14. Update of alien fauna and new records from Tunisian marine waters

    Directory of Open Access Journals (Sweden)

    K. OUNIFI- BEN AMOR

    2014-06-01

    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.

  15. 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...

  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. 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...

  18. 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...

  19. 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.

  20. 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. ...

  1. 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...

  2. 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 welfare

  3. Global networks for invasion science: benefits, challenges and guidelines

    DEFF Research Database (Denmark)

    Packer, Jasmin G.; Meyerson, Laura A.; Richardson, David M.;

    2016-01-01

    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...

  4. 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 welfare n

  5. 农林外来有害生物红火蚁入侵的问题建构与社会管理研究%A Study on Problems Construction and Social Management of Invasion of the Invasive Alien Species Solenpsisinvicta

    Institute of Scientific and Technical Information of China (English)

    张波; 罗映鹏; 雷益勤; 王艳玲; 骆小华; 黄秀颖; 向安强

    2015-01-01

    Solenpsisinvicta is the main invasive species in China and it is also one of the most damaging invasive species in the list of International Union for Conservation of Nature and Natural Resources. It is a pest which is detrimental to human or human concerns including agriculture, commercialtrade and travel. Applying the social construction theory within sociology of environment, the article aims to analyze the occurrence of invasion of Solenpsisinvicta. The goal is to study how has the invasion of the Solenpsisinvicta been constructed a problem in China, from the perspective of media, environment and its control. The article also tries to explore countermeasure of Splenpsisinvicta and the mechanism of the social management in the context of social science and natural science.%红火蚁是中国主要外来入侵物种,也是世界自然保护联盟收录的最具破坏力的入侵生物之一,它是一种危害农业生产、影响人民生活和旅游贸易的检疫性有害生物。利用环境社会学的问题建构理论,分析红火蚁入侵问题的发生机理,从媒体传播方式、红火蚁危害性、环境主张等方面,论证红火蚁入侵问题的建构过程;从自然科学与社会科学两方面,探讨相关问题的防范措施和社会管理机制。

  6. 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...

  7. 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...

  8. 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. ...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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)...

  19. 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,...

  20. 7 CFR 273.4 - Citizenship and alien status.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false Citizenship and alien status. 273.4 Section 273.4... and alien status. (a) Household members meeting citizenship or alien status requirements. No person is...)(4)(i) of this section, or (5) An individual who is both a qualified alien as defined in paragraph...

  1. 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.

  2. Standardization of DNA extraction from invasive alien weed ...

    African Journals Online (AJOL)

    Tuoyo Aghomotsegin

    method constituting high salt concentration to remove polysaccharides. The increased ... and quality DNA was obtained by this method. .... also acts as a good detergent that solubilizes cell wall, ... done to get rid of pigments. Isolation of RNA ...

  3. Standardization of DNA extraction from invasive alien weed ...

    African Journals Online (AJOL)

    DNA isolation from the weed, Parthenium hysterophorus is complicated due to the ... version of cetyltrimethylammonium bromide (CTAB) method constituting high ... The resulted genomic DNA showed fine random amplified polymorphic DNA ...

  4. Alien invasions in Antarctica—is anyone liable?

    Directory of Open Access Journals (Sweden)

    Kevin A. Hughes

    2014-05-01

    Full Text Available The introduction of non-native species to Antarctica in association with human activities is a major threat to indigenous biodiversity and the region's unique ecosystems, as has been well-demonstrated in other ecosystems globally. Existing legislation contained in the Protocol on Environmental Protection to the Antarctic Treaty does not specifically make the eradication of non-native species mandatory, although it is implicit that human-assisted introductions should not take place. Furthermore, to date, eradications of non-native species in the Treaty area have been infrequent and slow to progress. In 2005 an additional Annex (VI to the Protocol was agreed concerning “Liability arising from environmental emergencies.” This annex focusses on prevention of environmental emergencies, contingency planning and reclaiming costs incurred when responding to an environmental emergency caused by another operator within the Antarctic Treaty area. However, the types of environmental emergencies covered by the annex are not defined. In this paper we highlight potential difficulties with the application of Annex VI in the context of non-native species control and eradication, including, for example, whether a non-native species introduction would be classified as an “environmental emergency” and therefore be considered under the terms of the annex. Even if this were the case, we conclude that the slow pace of approval of the annex by Antarctic Treaty Parties may prevent it coming into force for many years and, once in force, in its current form it is unlikely to be useful for reclaiming costs associated with the eradication or management of a non-native species.

  5. Satellite-based annual evaporation estimates of invasive alien plant ...

    African Journals Online (AJOL)

    2013-12-17

    Dec 17, 2013 ... Water (WFW) programme, have on total evaporation (ET) and the availability of water resources in two highly-invaded ... on water resources were based on the results from the paired catchment ...... Tourism, Pretoria. 85 pp.

  6. Freshwater Fungal Infections

    Directory of Open Access Journals (Sweden)

    Dennis J. Baumgardner

    2017-01-01

    Full Text Available Fungal infections as a result of freshwater exposure or trauma are fortunately rare. Etiologic agents are varied, but commonly include filamentous fungi and Candida. This narrative review describes various sources of potential freshwater fungal exposure and the diseases that may result, including fungal keratitis, acute otitis externa and tinea pedis, as well as rare deep soft tissue or bone infections and pulmonary or central nervous system infections following traumatic freshwater exposure during natural disasters or near-drowning episodes. Fungal etiology should be suspected in appropriate scenarios when bacterial cultures or molecular tests are normal or when the infection worsens or fails to resolve with appropriate antibacterial therapy.

  7. 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

  8. Papahanaumokuakea - Laysan Island Invasive Plant Monitoring and Control with Volunteers 2012

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project supports restoration activities at Laysan Island. Staff and volunteers continue efforts to eradicate alien invasive species Indian dropseed (Sporobolus...

  9. A new record of the freshwater jellyfish Craspedacusta sowerbii Lankester, 1880 (Hydrozoa) in Southeastern Anatolia (Turkey)

    Science.gov (United States)

    Bekleyen, Aysel; Varol, Memet; Gokot, Bulent

    2011-03-01

    We report the first record of the invasive freshwater jellyfish Craspedacusta sowerbii Lankester in Kralkizi Dam Lake, Southeastern Anatolia, Turkey. The medusa was found only in August, 2008 when average surface water temperatures were 26.9°C.

  10. A new record of the freshwater jellyfish Craspedacusta sowerbii Lankester, 1880 (Hydrozoa) in Southeastern Anatolia (Turkey)

    Institute of Scientific and Technical Information of China (English)

    Aysel BEKLEYEN; Memet VAROL; Bulent GOKOT

    2011-01-01

    We report the first record of the invasive freshwater jellyfish Craspedacusta sowerbii Lankester in Kralkizi Dam Lake, Southeastern Anatolia, Turkey. The medusa was found only in August, 2008 when average surface water temperatures were 26.9℃.

  11. Monitoring of the invasive diatom Didymosphenia geminata in the subarctic and in alpine areas of southern Europe

    Science.gov (United States)

    Finger, David C.; Jónsson, Ingi R.; Cypaité, Vaiva; Ognjanova, Nadja; Ólafsson, Jón S.; Trichkova, Teodora

    2016-04-01

    In recent decades invasive species have been spreading across Europe. Although the perceptions of invasive species are divergent among researchers there is a general consent that invasive species endanger the diversity of native biota and hence should be monitored to initiate appropriate counter measures in drastic cases. Anthropogenic activities and climate change are the main cause for the enhanced spreading of non-native species to new environments. In this presentation we will present preliminary results from two aquatic case studies, one located in subarctic Iceland (River Elliðaár) and one in the high mountains of Bulgaria (the Seven Rila lakes), focusing on the freshwater diatom Didymosphenia geminata (Didymo). The diatom is a single cell algae which's natural habitat is cold fresh water environments with low nutrient content, i.e. mountainous areas in Europe, Asia and North America. In the last decades Didymo has been increasingly observed in new areas, e.g. Iceland, North America and New Zealand. Within the ESENIAS-TOOLS project two field excursions will identify the existence of Didymo in the two study sites and compare current abundance to previous observations. The preliminary results in the Rila Mountains, including both fossil and recent records, confirm that the occurrence of Didymo is restricted to Lake Bliznaka, the largest of the seven lakes located at lower altitude. In River Elliðaár preliminary results indicate a high abundance of Didymo along all sampling locations, confirming the invasive proliferation described in previous studies. The upscaling of the preliminary results from Elliðaár and Rila Mountains can help us to formulate general conclusions about the spreading of this invasive species. Furthermore, this bilateral cooperation can be further extended to other countries and hence contribute to a better management of invasive alien species in Europe. Acknowledgement: This study is part of ESENIAS - The East and South European

  12. 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

    2014-02-01

    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.

  13. Freshwater sponges of Suriname

    NARCIS (Netherlands)

    Ezcurra de Drago, Inés

    1975-01-01

    This paper is the first contribution to the knowledge of the freshwater sponges of Suriname. Four species have been identified up till now: Metania spinata (Carter, 1881), Trochospongilla paulula (Bowerbank, 1863), Radiospongilla crateriformis (Potts, 1882), and Drulia uruguayensis Bonetto & Ezcurra

  14. Freshwater Harmful Algal Blooms

    Science.gov (United States)

    EPA is seeking regular and early career applications proposing innovative research on the prediction, prevention, control and mitigation of freshwater HABs as well as the drivers, life cycle patterns, and fate of and effects from from less-common, less

  15. 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.

  16. Alien Marine Species in the Mediterranean - the 100 ‘Worst Invasives’ and their Impact

    Directory of Open Access Journals (Sweden)

    N. STREFTARIS

    2012-12-01

    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.

  17. 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.

  18. 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.

  19. Alien species on the coasts of Turkey

    Directory of Open Access Journals (Sweden)

    M.E. CINAR

    2012-12-01

    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.

  20. AliEn - EDG Interoperability in ALICE

    CERN Document Server

    Bagnasco, S; Buncic, P; Carminati, F; Cerello, P G; 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, Storage Element and Computing Element), and act as interface nodes between the systems. An EDG Resource Broker is seen by the AliEn server as a single Computing Element, while the EDG storage is seen by AliEn as a single, large Storage Element; files produced in EDG sites are registered in both the EDG Replica Catalogue and in the AliEn Data Catalogue, thus ensuring accessibility from both worlds. In fact, both registrations are required: the AliEn one is used for the data management, the EDG one to guarantee the integrity and...