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Effect of the Internet Commerce on Dispersal Modes of Invasive Alien Species  [PDF]
Magdalena Lenda, Piotr Skórka, Johannes M. H. Knops, Dawid Moroń, William J. Sutherland, Karolina Kuszewska, Micha? Woyciechowski
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0099786
Abstract: 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.
The distribution and introduction pathway of alien invasive species in China

生物多样性 , 2004,
Abstract: Alien invasive species have become a serious environmental issue throughout the world. It is necessary to launch a nationwide investigation on alien invasive species, so as to obtain baseline data, identify causes of invasion, and put forward effective control strategies and measures. Data on classification, origin, pathway and environmental impacts of alien invasive micro-organisms, invertebrates, amphibians and reptiles, fish, birds, mammals, weeds, trees in terrestrial and aquatic ecosystems and alien invasive species in marine ecosystems of China were analyzed, based on literature research, field survey and consultation. 283 alien invasive species have been identified in China, and the number of species of alien invasive micro-organisms, aquatic plants, terrestrial plants, aquatic invertebrates, terrestrial invertebrates, amphibians and reptiles, fish, and mammals were 19, 18, 170, 25, 33, 3, 10, and 5, respectively. The proportion of alien invasive species originating from America, Europe, Asia, Africa and Oceania were 55.1%, 21.7%, 9.9%, 8.1% and 0.6%, respectively. Many institutions and individuals in China lack adequate knowledge of ecological and environmental consequences caused by alien invasive species, with some blindness in the introduction of alien species. For instance, 50.0% of alien invasive plants were intentionally introduced as pasture, feed stock, ornamental plants, textile plants, medicinal plants, vegetables, or lawn plants. 25% of alien invasive animals were intentionally introduced for cultivation, recreation, or biological control. In addition, much effort has been made on introduction of alien species, and little attention has been paid to the management of introduced alien species, which may allow their escape into natural environments and potential threats to the environment. There are also gaps in the quarantine system in China. All invasive micro-organisms were unintentionally introduced, through timber, seedlings, flowerpots, or soil. 76.3% of alien invasive animals invaded through commodity or transportation facilities because of the failure of quarantine. It is recommended that quarantine measures should be strictly implemented. At the same time, the intentional introduction of alien species should be strictly managed and a system of risk assessment should be implemented.
Determining a charge for the clearing of invasive alien plant species (IAPs) to augment water supply in South Africa
JN Blignaut, C Marais, JK Turpie
Water SA , 2007,
Abstract: South Africa is running out of water supply options. One option, however, is to control invasive alien plant species (IAPs) within water catchment areas and in riparian zones. The National Water Act and subsequent documentation provide a guide for the use of economic instruments to manage invasive alien plant species at a national, but also at a water management area level. This paper determines the method and level of such an invasive alien plant control charge as part of the water resource management charge.
Changes in invasive pneumococcal disease serotypes in a regional area of Australia following three years of 7vPCV introduction  [cached]
Tove Fitzgerald,Peter D Massey,Fakhrul Islam
Western Pacific Surveillance and Response , 2012,
Abstract: Background: Invasive pneumococcal disease (IPD) is a serious bacterial disease. Vaccination can prevent disease for many of the current serotypes. The aim of this investigation was to describe the notification rates of IPD in a regional area of Australia, explore changes in rates since the introduction of the population vaccine programmes in 2005 and to describe changes in the distribution of serotypes in relation to the available vaccines after three years.Methods: Annualized IPD notification rates were calculated for residents of a regional area in northern New South Wales. Rates were analysed according to serotypes covered by available vaccines. Changes in serotypes were compared for the periods 2002–2004 and 2008–2010.Results: The annualized notification rate of IPD in all ages for the period 2002–2004 was 13.7 per 100 000 population and 8.3 per 100 000 population for the period 2008–2010 (rate ratio [RR], 0.61, confidence interval [CI]: 0.51–0.72). The largest decline was observed in 7-valent pneumococcal conjugate vaccine (7vPCV) types across all age groups (RR, 0.17, CI: 0.12–0.24) and in the zero to four year age group (RR, 0.03, CI: 0.01–0.11). The six serotypes included in the new 13-valent pneumococcal conjugate vaccine, but not in the 7vPCV, accounted for 40.6% of IPD cases in the zero to four year age group during the period of 2008–2010.Discussion: The introduction of 7vPCV significantly reduced the overall notification rate of IPD caused by the serotypes contained in this vaccine. This decline in IPD rates in children can be directly attributed to the use of 7vPCV, and in adults it is most likely an indirect effect of the 7vPCV programme in children.
Nuclear DNA C-value of alien invasive and native plants and its relationship with invasiveness
外来入侵植物和本地植物核DNA C-值的比较及其与入侵性的关系

FU Gai-lan,FENG Yu-long,

生态学杂志 , 2007,
Abstract: The nuclear DNA C-values of 13 alien invasive, 6 native and 1 alien non-invasive plant species from 10 genera of 8 families were measured with flow cytometer. The mean nuclear DNA C-value of the 13 alien invasive species was significantly lower than those of the native and alien non-invasive species, but no consistent regularity was found for the different species of same genus. In the four genera including both alien invasive and native species, all the alien invasive species in Eupatorium and Bidens and one of the two alien invasive species in Alternanthera had significantly lower nuclear DNA C-values than their native congeners, while the alien invasive species in Peperomia had significantly higher nuclear DNA C-values than the native species. There was no certain correlation between nuclear DNA C-value and alien plant invasiveness.
Impacts of invasive alien plants on water quality, with particular emphasis on South Africa
J Chamier, K Schachtschneider, DC le Maitre, PJ Ashton, BW van Wilgen
Water SA , 2012,
Abstract: We review the current state of knowledge of quantified impacts of invasive alien plants on water quality, with a focus on South Africa. In South Africa, over 200 introduced plant species are regarded as invasive. Many of these species are particularly prominent in riparian ecosystems and their spread results in native species loss, increased biomass and fire intensity and consequent erosion, as well as decreased river flows. Research on the impact of invasive alien plants on water resources has historically focused on water quantity. However, although invasive alien plants also affect the quality of water, this aspect has not been well documented. Alien invasive plants increase evaporation rates, and reduce stream flow and dilution capacity. The biomass inputs of alien invasive plants, especially nitrogen fixers such as Acacia spp., alter nutrient cycles and can elevate nutrient concentrations in groundwater. Alien plant invasions alter the fire regimes in invaded areas by changing the size, distribution and plant chemistry of the biomass. More intense fires increase soil erosion and thereby decrease water quality. In contrast to riparian invasions, aquatic invasive plants have been more extensively studied in South Africa and their impacts on water quality have been relatively well monitored. Water quality in South Africa is rapidly deteriorating, and all factors that influence this deterioration need to be taken into account when formulating actions to address the problem. The changes in water quality brought about by alien plant invasions can exacerbate the already serious water quality problems.
Public attitude in the city of Belgrade towards invasive alien plant species
Tomi?evi? Jelena,Grbi? Mihailo,Sko?aji? Dragana,Radovanovi? Dragana
Glasnik ?umarskog Fakulteta , 2012, DOI: 10.2298/gsf1205189t
Abstract: 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.
The casual, naturalised and invasive alien flora of Zimbabwe based on herbarium and literature records  [cached]
Alfred Maroyi
Koedoe : African Protected Area Conservation and Science , 2012,
Abstract: 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.
Assessment and Management of Invasive Alien Predators  [cached]
Kirsty Park
Ecology and Society , 2004,
Abstract: 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 hypothesis-driven experimental approach to impact assessment, and to eradication efforts through adaptive management, would benefit our ecological understanding of invasive species without delaying critical management action that could reduce the spread of invasive species populations
Investigation on Alien Invasive Plants in the Nansihu Lake Wetland of Shandong Province

植物学报 , 2010,
Abstract: The Nansihu Lake wetland is one of the largest freshwater lake wetlands in China; its eco-environment plays an important role in flood storage, climatic regulation, water conservation and purification, and maintenance of biologicaldiversity. Evaluating the impact of alien invasive plants on biodiversity and the effect of exotic plant invasions on ecosystem processes by surveying all ranges of the Nansihu Lake wetland is vital. Literature search and field investigation were used to study alien invasive plants in Nansihu Lake wetland. A comparison of the species composition of alien invasive plants in Nansihu Lake wetland and in Qingdao, Mt. Kunyu and Binzhou coastal areas showed 41 species of alien invasive plants belonging to 19 families and 35 genera in the Nansihu Lake wetland. The largest families were Compositae and Leguminosae. The proportion of alien invasive species originating from the tropic zone was close to that from temperate regions. The proportion of alien invasive plants caused by intentional introduction was 39%. The number of alien invasive plants in Qingdao, Mt. Kunyu and Binzhou was greater than that in the Nansihu Lake wetland. The number of species in the most developed region Qingdao was the greatest. In total, 35 species found in Qingdao were not found in the Nansihu Lake wetland. Five alien invasive species were specific to the Nansihu Lake wetland and showed the aquatic plant characteristics of exotic invasive plants in the Nansihu Lake wetland. Similarity analysis revealed consistent Jaccard and Sorenson indexes, with the Nansihu Lake wetland most similar to Binzhou, then Kunyu areas and least similar to the Qingdao area. Combined with regulation analysis of alien invasive plants in Nansihu Lake wetland, corresponding countermeasures are suggested.
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