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Franziska Humair Luc Humair Fabian Kuhn Christoph Kueffer 《Conservation biology》2015,29(6):1658-1665
Biological invasions are a major concern in conservation, especially because global transport of species is still increasing rapidly. Conservationists hope to anticipate and thus prevent future invasions by identifying and regulating potentially invasive species through species risk assessments and international trade regulations. Among many introduction pathways of non‐native species, horticulture is a particularly important driver of plant invasions. In recent decades, the horticultural industry expanded globally and changed structurally through the emergence of new distribution channels, including internet trade (e‐commerce). Using an automated search algorithm, we surveyed, on a daily basis, e‐commerce trade on 10 major online auction sites (including eBay) of approximately three‐fifths of the world's spermatophyte flora. Many recognized invasive plant species (>500 species) (i.e., species associated with ecological or socio‐economic problems) were traded daily worldwide on the internet. A markedly higher proportion of invasive than non‐invasive species were available online. Typically, for a particular plant family, 30–80% of recognized invasive species were detected on an auction site, but only a few percentages of all species in the plant family were detected on a site. Families that were more traded had a higher proportion of invasive species than families that were less traded. For woody species, there was a significant positive relationship between the number of regions where a species was sold and the number of regions where it was invasive. Our results indicate that biosecurity is not effectively regulating online plant trade. In the future, automated monitoring of e‐commerce may help prevent the spread of invasive species, provide information on emerging trade connectivity across national borders, and be used in horizon scanning exercises for early detection of new species and their geographic source areas in international trade. 相似文献
404.
Apps are small task-orientated programs with the potential to integrate the computational and sensing capacities of smartphones with the power of cloud computing, social networking, and crowdsourcing. They have the potential to transform how humans interact with nature, cause a step change in the quantity and resolution of biodiversity data, democratize access to environmental knowledge, and reinvigorate ways of enjoying nature. To assess the extent to which this potential is being exploited in relation to nature, we conducted an automated search of the Google Play Store using 96 nature-related terms. This returned data on ~36 304 apps, of which ~6301 were nature-themed. We found that few of these fully exploit the full range of capabilities inherent in the technology and/or have successfully captured the public imagination. Such breakthroughs will only be achieved by increasing the frequency and quality of collaboration between environmental scientists, information engineers, computer scientists, and interested publics. 相似文献
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David M Lodge Susan Williams Hugh J MacIsaac Keith R Hayes Brian Leung Sarah Reichard Richard N Mack Peter B Moyle Maggie Smith David A Andow James T Carlton Anthony McMichael 《Ecological applications》2006,16(6):2035-2054
The Ecological Society of America has evaluated current U.S. national policies and practices on biological invasions in light of current scientific knowledge. Invasions by harmful nonnative species are increasing in number and area affected; the damages to ecosystems, economic activity, and human welfare are accumulating. Without improved strategies based on recent scientific advances and increased investments to counter invasions, harm from invasive species is likely to accelerate. Federal leadership, with the cooperation of state and local governments, is required to increase the effectiveness of prevention of invasions, detect and respond quickly to new potentially harmful invasions, control and slow the spread of existing invasions, and provide a national center to ensure that these efforts are coordinated and cost effective. Specifically, the Ecological Society of America recommends that the federal government take the following six actions: (1) Use new information and practices to better manage commercial and other pathways to reduce the transport and release of potentially harmful species; (2) Adopt more quantitative procedures for risk analysis and apply them to every species proposed for importation into the country; (3) Use new cost-effective diagnostic technologies to increase active surveillance and sharing of information about invasive species so that responses to new invasions can be more rapid and effective; (4) Create new legal authority and provide emergency funding to support rapid responses to emerging invasions; (5) Provide funding and incentives for cost-effective programs to slow the spread of existing invasive species in order to protect still uninvaded ecosystems, social and industrial infrastructure, and human welfare; and (6) Establish a National Center for Invasive Species Management (under the existing National Invasive Species Council) to coordinate and lead improvements in federal, state, and international policies on invasive species. Recent scientific and technical advances provide a sound basis for more cost-effective national responses to invasive species. Greater investments in improved technology and management practices would be more than repaid by reduced damages from current and future invasive species. The Ecological Society of America is committed to assist all levels of government and provide scientific advice to improve all aspects of invasive-species management. 相似文献
407.
Irena Rot-Nikcevic Christopher N. Taylor Richard J. Wassersug 《Behavioral ecology and sociobiology》2006,60(1):116-25
Tadpoles can alter their behavior, morphology, and life history in response to habitat change. Although chemical signals from
conspecifics or predators play an important role in tadpole habitat assessment, little is known about the role of visual cues
and the extent to which tadpoles rely on their vision for intraspecific social assessment. The aim of our experiments was
to determine whether larval anurans use visual images of other tadpoles as indicators of density and to analyze how, and to
what extent, images of conspecifics alone affect tadpole development, growth, and behavior. To assess this, we raised both
Rana sylvatica and Bufo americanus tadpoles in aquaria with either quarter- or half-mirrored walls. Both physically increased density and increased density
simulated with mirrors decreased tadpole growth and developmental rates, and increased activity in Rana tadpoles. Bufo tadpoles did not significantly alter their growth and development in response to visually increased density. Only true, i.e.,
physically, increased density had an effect on growth and activity in Bufo tadpoles. Our data show that images of conspecifics are used as visual cues by Rana tadpoles and can induce phenotypically plastic changes in several traits. This response to visual cues is taxon-specific.
An erratum to this article can be found at 相似文献
408.
Joyeeta Gupta Richard Howarth Peter Sand Oran Young 《Environmental geochemistry and health》2004,26(4):435
Announcement
International Environmental Agreements:Politics, Law and Economics (INEA) 相似文献409.
410.
Richard Ogutu-Ohwayo 《Conservation biology》1993,7(3):701-711
As in Lake Victoria and Lake Kyoga, most of the native fish species of Lake Nabugabo have either been depleted or have disappeared since Lates niloticus , Nile perch, and Oreochromis niloticus , a tilapiine, were introduced. L. niloticus, O. niloticus, Schilbe intermedius, Brycinus jacksonii , and Rastrineobola argentea are the only species still abundant and widespread in the lake. Of the five haplochromine species endemic to Lake Nabugabo, at least one has vanished and the remaining ones are very rare. The prey of the Nile perch in Lake Nabugabo, with the exception of the prawn Caridina nilotica , which is absent from the lake, are similar to those the predator switched to in Lakes Victoria and Kyoga after haplochromines had been depleted. These consist of ephemeropterans—especially Povilla , the anisopteran nymphs R. argentea , tilapiines, and juvenile Nile perch. Three small lakes adjacent to Lake Nabugabo—Lake Kayanja, Lake Kayugi, and Lake Manywa—contain large numbers of Oreochromis esculentus and two haplochromine species previously known only in Lake Nabugabo. These three lakes should be designated conservation areas for the cichlids and other native species that were previously abundant in Lakes Victoria, Kyoga, and Nabugabo. The swamps around these lakes should be protected so that the Nile perch does not spread into them. Further research should be carried out to ensure the preservation of the endemic species. 相似文献