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2. Alien fish species in the Czech Republic and their impact on the native fish fauna
- Creator:
- Lusk, Stanislav, Lusková, Věra, and Hanel, Lubomír
- Type:
- article and TEXT
- Subject:
- introduction, translocation, and invasion
- Language:
- English
- Description:
- Over the past 150 years, the waters of the Czech Republic were experimentally stocked or invaded by a total of 41 alien (non-native) fish species. The following species have become fully naturalized and produced self-sustained populations: Carassius gibelio, Pseudorasbora parva, Ameiurus nebulosus and Gasterosteus aculeatus, which produced stable populations in several spatially limited localities. In some cases Oncorhynchus mykiss, Salvelinus fontinalis and Coregonus maraena will produce instable temporary populations based on released material obtained from fish farms and ponds. The occurrence of the remaining acclimatized alien species (Coregonus peled, Ctenopharyngodon idella, Hypophthalmichthys molitrix, Aristichthys nobilis) in natural ecosystems and fishponds depends on stocking fish obtained from artificial spawning and cultures. The documented annual average production of alien species fit for human consumption amounts to around 2 000 tonnes, i.e. 8.2 % of the annual average production of marketable fish cultures in the Czech Republic. A significant negative impact of the introduced species on native ichthyofauna has been ascertained as regards its ecological, biological properties, biodiversity and health. Considered a typical invasive alien species, Carassius gibelio heavily depressed the occurrence and numbers of indigenous Carassius carassius populations and also contributed to the decreased numbers of Tinca tinca, Leucaspius delineatus and other native cyprinid fish. P. parva and A. nebulosus show a much weaker and limited impact. The introduction of C. idella was accompanied by the introduction of the tapeworm species, Bothriocephalus gowkongensis, which subsequently caused heavy losses in cultures of Cyprinus carpio. In 2008, Neogobius melanostomus was recorded for the first time in this country at the confluence of the Morava and Dyje rivers.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
3. Alien invasive fish species in Polish waters
- Creator:
- Grabowska, Joanna, Kotusz, Jan, and Witkowski, Andrzej
- Type:
- article and TEXT
- Subject:
- non-indigenous species, introduction, invasion, and impact of exotic species
- Language:
- English
- Description:
- For the last 800 years, 35 alien fish species have been introduced, mainly intentionally, in Polish inland waters. The paper reviews the present state of alien fish fauna in Poland, with special attention paid to those considered to be invasive. Till now 26 species have been reported as naturalized, acclimatized or casual and it means that 34% of fish fauna are non-indigenous species. The majority came from North America, Eastern Asia and Siberia or different regions of Europe. More than 65 % of all introductions took place in the last 60 years. After the World War II the rapid expansion was noted specially for brown bullhead, Ameiurus nebulosus and gibel, Carassius gibelio. In the recent decade similar explosive spread has been observed for three Neogobius species (round goby, N. melanostomus, racer goby, N. gymnotrachelus, monkey goby, N. fluviatilis), Amur sleeper, Perccottus glenii and topmouth gudgeon, Pseudorasbora parva. The occurrence of introduced fish species resulted in several negative changes in aquatic environments. Some of them are as follows: hybridisation with native species, destruction of spawning grounds and habitats for many freshwater organisms, decrease of native fish reproduction success due to predation on eggs and offspring and finally the aliens might be vectors for parasites and diseases.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
4. Changes in the spatio-temporal patterns and habitat preferences of Ambrosia artemissiofolia during its invasion of Austria
- Creator:
- Essl, Franz, Dullinger, Stefan, and Kleinbauer, Ingrid
- Type:
- article and TEXT
- Subject:
- climate change, human health, introduction history, invasion, naturalization, niche expansion, species distribution models, and spread
- Language:
- English
- Description:
- The invasion of Austria by the alien vascular plant Ambrosia artemisiifolia (Asteraceae) is analysed in detail, based on a survey of available records. In total, 697 records were collated. The first record for Austria is a herbarium specimen collected in 1883. Up to the end of the 1940s, records were rare and only of casual populations resulting from long-distance dispersal. Since the 1950s, the number of records has increased exponentially, and more than one third of all records (242) were collected in the last 5-year period (2001–2005) included in the survey. The first naturalized population was recorded in 1952, nearly 70 years after the first record of a casual population. Recently, the number of naturalized populations increased considerably faster than that of casual populations. Several pathways (contaminated crops and bird seed, agricultural machines, transport of soil) have contributed to the high levels of propagule pressure and this successful invasion. Ambrosia artemisiifolia has undergone a niche expansion during the invasion process. Up to 1950, most records were from sites along railway routes, whereas in the period 1950–1974 itwas mostly ruderal habitats, not associated with traffic infrastructure, which were colonized. Since the 1970s, records from roadsides have increased strongly and now dominate. Fields were colonized first in the 1970s and since then have gained in importance. The distribution of naturalized populations was related to environmental and climatic variables by means of a generalized linear model. Their distribution in Austria is closely related to temperature. Landscape variables, describing aspects of habitat availability (topography, land use, major street density) also significantly explain the current distribution of A. artemisiifolia. Suitable habitats currently occur mainly in the eastern and southeastern lowlands. We conclude that global warming will disproportionally enhance the invasion success of A. artemisiifolia in Austria, even if there is only a slight increase in temperature, as significant areas of agricultural land in Austria are currently only slightly too cool for A. artemisiifolia. The widespread occurrence of this species will have serious consequences for human health and agriculture.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
5. Cloning, expression and characterisation of a cysteine protease from Trichinella spiralis
- Creator:
- Song, Yan Yan, Wang, Li Ang, Ren, Hua Na, Qi, Xin, Sun, Ge Ge, Liu, Ruo Dan, Jiang, Peng, Zhang, Xi, Cui, Jing, and Wang, Zhong Quan
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, Trichinellosis, cysteine protease, invasion, development, 2, and 59
- Language:
- English
- Description:
- Cysteine protease is a superfamily of widespread proteolytic enzymes and plays a major role in larval invasion, migration, exsheathing, survival and immune evasion in parasites. In the present study, the gene coding cysteine proteinase of the nematode Trichinella spiralis (Owen, 1835) was cloned into pQE-80L and subsequently expressed in E. coli JM109. The rTsCP was purified and its antigenicity was identified by Western blot and ELISA. Using anti-rTsCP serum the native TsCP was identified in muscle larval crude proteins. The results of quantitative real-time PCR and immunofluorescence test demonstrated that the TsCP was expressed in all stages of T. spiralis and located mainly in cuticle, stichosome and reproductive organs. The immunisation of mice with rTsCP elicited Th2-predominant immune responses. Anti-rTsCP antibodies could partially inhibit the in vitro larval invasion of intestinal epithelial cells and kill the newborn larvae by an antibody-dependent cell-mediated dose-dependent cytotoxicity. The vaccinated mice exhibited a 54% reduction of adults and a 33% reduction of muscle larvae following challenge infection. The results suggested that the TsCP might be an indispensable protein in Trichinella invasion, development and survival of T. spiralis in hosts, and could be a potential vaccine target against infection., Yan Yan Song, Li Ang Wang, Hua Na Ren, Xin Qi, Ge Ge Sun, Ruo Dan Liu, Peng Jiang, Xi Zhang, Jing Cui, Zhong Quan Wang., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6. Differences in germination and seedling establishment of alien and native Impatiens species
- Creator:
- Perglová, Irena, Pergl, Jan, Skálová, Hana, Moravcová, Lenka, Jarošík, Vojtěch, and Pyšek, Petr
- Type:
- article and TEXT
- Subject:
- alien species, congeneric comparison, dormancy, germination, Impatiens, invasion, RGR, and seed bank
- Language:
- English
- Description:
- Comparative studies of closely related species may provide useful insights into the effect of species traits on invasion success since some of the biases associated with multispecies studies, such as phylogenetic effects, are considerably reduced by virtue of the experimental design. In this study seed and seedling traits of three congeneric alien species in Europe, differing in their region of origin, invasion status and history (Impatiens glandulifera, I. parviflora, I. capensis), were compared with the native I. noli-tangere in laboratory and common garden experiments. Seeds of I. glandulifera required the shortest period of stratification, germinated well both under laboratory and experimental garden conditions and the seedlings produced more biomass than those of the other species. Seeds of I. parviflora required a longer period of stratification, had the highest percentage germination but seedling emergence in the experimental garden was poorer than in I. glandulifera. Neither of these two species invasive in the Czech Republic formed soil seed banks. The native I. noli-tangere had the lowest percentage germination and formed a short-term persistent seed bank. Impatiens capensis germinated well in the laboratory, had the highest seedling emergence in the garden and its seed remained viable in the soil for three years. This indicates that in terms of germination and emergence, this species is comparable with the two invasive alien congeners and there appear to be no constraints to its invasion in the Czech Republic where it does not occur yet. Its absence may be due to a low propagule pressure; in the national flora I. capensis is listed as a potential future invader without mentioning it being cultivated in this country. Our results indicate that differences in the invasiveness of three alien species of balsams in the temperate zone of Central Europe can be attributed, at least in part, to their differing performances in the early stages of their life cycle. The short period of time required for seed stratification and the high seedling biomass of I. glandulifera might have increased its invasion potential compared to other Impatiens species occurring in the Czech Republic.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
7. Environmental and land-use variables determining the abundance of Ambrosia artemisiifolia in arable fields in Hungary
- Creator:
- Pinke, Gyula, Karácsony, Péter, Czúcz, Bálint, and Botta-Dukát, Zoltán
- Type:
- article and TEXT
- Subject:
- agriculture, arable fields, decision trees, invasion, invasive plants, ragweed, weed distribution, and weed ecology
- Language:
- English
- Description:
- Ambrosia artemisiifolia is the most noxious invasive species of weed in Hungary. The aim of this study was to quantify the environmental and land-use factors that explain the variance in its abundance in arable fields. A survey of 243 arable fields was carried out across Hungary, and 19 environmental and 12 land-use factors were measured. These were used as explanatory variables in classification and regression tree models. The abundance of A. artemisiifolia was significantly higher at the edges than at the centres of fields. The most important land-use variables explaining the variance in abundance of A. artemisiifolia were crop type and crop cover, with the highest abundance recorded in sunflower fields and fields with low crop cover. The following explanatory environmental variables were associated with significantly higher A. artemisiifolia abundance: sandy or acidic soils, mean April precipitation > 39 mm, mean annual precipitation > 592 mm and mean May temperature < 15.5 °C. Ambrosia artemisiifolia was significantly less abundant in fields with soils containing high concentrations of Na, K and Mn. Both farmers and nature conservationists should be made aware of the conditions and practices that favour ragweed so that they can develop effective and selective ragweed control practices, particularly in arable habitats with a high diversity of weeds.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
8. expansion and occurrence of the Amur sleeper (Perccottus glenii) in eastern Slovakia
- Creator:
- Koščo, Ján, Lusk, Stanislav, Halačka, Karel, and Lusková, Věra
- Type:
- article and TEXT
- Subject:
- Perccottus glenii, exotic species, invasion, and Tisza river basin
- Language:
- English
- Description:
- The Amur sleeper, Perccottus glenii Dybowski, 1877, is indigenous in eastern Asia. During the second half of the 20th century, with the aid of man, it spread over the eastern part of Europe as well as in central Asia. In the course of 50 years of its dispersal in the western direction the species already reached the Vistula drainage area (the Baltic Sea basin) and the Danube drainage area (the Black Sea basin). In the latter basin, its occurrence was ascertained in the drainage area of the Tisza river in Hungary in 1997. In eastern Slovakia, the Amur sleeper was first recorded in 1998 in the Latorica drainage area. In the course of subsequent years it has become a common species in the streams in the basins of the Latorica, Bodrog and Tisza rivers. In shallow lentic waters densely grown with aquatic plants the species becomes a superdominant or even exclusive species in the local fish communities. It has no marketable value but presents a serious threat to the existence of native fish species with similar identical microhabitat requirements.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
9. Genome size as a marker for identifying the invasive alien taxa in Fallopia section Reznoutria
- Creator:
- Suda, Jan, Trávníček, Pavel, Mandák, Bohumil, and Berchová-Bímová, Kateřina
- Type:
- article and TEXT
- Subject:
- flow cytometry, genome size, homoploid groups, hybridization, invasion, knotweed, nuclear DNA amount, and ploidy
- Language:
- English
- Description:
- DAPI and propidium iodide flow cytometry were used to determine the variation in genome size in 166 samples and of all taxa and ploidy levels of Fallopia section Reynoutria (knotweeds) recorded in the Czech Republic. Significant differences were detected in the amount of nuclear DNA, associated with the ploidy levels and taxonomic identity of the material. At each ploidy level, F. sachalinensis showed the lowest and F. japonica the highest fluorescence intensities. The fluorescence values for the hybridogenous F. ×bohemica were located in-between these two levels. In most cases, there was at least a four-percent gap in fluorescence values between the nearest neighbours belonging to a different taxon. Intraspecific variation in genome size was very low in all taxa except hexaploid F. ×bohemica; this could be due to the complex evolutionary history of this taxon. Our results indicate that the amount of nuclear DNA can be used as a reliable marker for the identification of homoploid knotweed species and their hybrids. Different evolutionary pathways for the origin of high polyploids and/or hybridogenous taxa are proposed based on genome size.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
10. Invasibility of tropical islands by introduced plants
- Creator:
- Daehler, Curtis C.
- Type:
- article and TEXT
- Subject:
- invasion, islands, Fiji, Hawaii, naturalization, New Caledonia, Pacific, pests, and Taiwan
- Language:
- English
- Description:
- All else being equal, more isolated islands should be more susceptible to invasion because their native species are derived from a smaller pool of colonists, and isolated islands may be missing key functional groups. Although some analyses seem to support this hypothesis, previous studies have not taken into account differences in the number of plant introductions made to different islands, which will affect invasibility estimates. Furthermore, previous studies have not assessed invasibility in terms of the rates at which introduced plant species attain different degrees invasion or naturalization. I compared the naturalization status of introduced plants on two pairs of Pacific island groups that are similar in most respects but that differ in their distances from a mainland. Then, to factor out differences in propagule pressure due to differing numbers of introductions, I compared the naturalization status only among shared introductions. In the first comparison, Hawai‘i (3700 km from a mainland) had three times more casual/weakly naturalized, naturalized and pest species than Taiwan (160 km from a mainland); however, roughly half (54%) of this difference can be attributed to a larger number of plant introductions to Hawai‘i. In the second comparison, Fiji (2500 km from a mainland) did not differ in susceptibility to invasion in comparison to New Caledonia (1000 km from a mainland); the latter two island groups appear to have experienced roughly similar propagule pressure, and they have similar invasibility. The rate at which naturalized species have become pests is similar for Hawai‘i and other island groups. The higher susceptibility of Hawai‘i to invasion is related to more species entering the earliest stages in the invasion process (more casual and weakly naturalized species), and these higher numbers are then maintained in the naturalized and pest pools. The number of indigenous (not endemic) species was significantly correlated with susceptibility to invasion across all four island groups. When islands share similar climates and habitat diversity, the number of indigenous species may be a better predictor of invasibility than indices of physical isolation because it is a composite measure of biological isolation.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/