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11.
Gordon H Copp J Robert Britton Julien Cucherousset Emili García‐Berthou Ruth Kirk Edmund Peeler Saulius Stakėnas 《Fish and Fisheries》2009,10(3):252-282
A popular species for food and sport, the European catfish (Silurus glanis) is well‐studied in its native range, but little studied in its introduced range. Silurus glanis is the largest‐bodied freshwater fish of Europe and is historically known to take a wide range of food items including human remains. As a result of its piscivorous diet, S. glanis is assumed to be an invasive fish species presenting a risk to native species and ecosystems. To assess the potential risks of S. glanis introductions, published and ‘grey’ literature on the species’ environmental biology (but not aquaculture) was extensively reviewed. Silurus glanis appears well adapted to, and sufficiently robust for, translocation and introduction outside its native range. A nest‐guarding species, S. glanis is long‐lived, rather sedentary and produces relatively fewer eggs per body mass than many fish species. It appears to establish relatively easily, although more so in warmer (i.e. Mediterranean) than in northern countries (e.g. Belgium, UK). Telemetry data suggest that dispersal is linked to flooding/spates and human translation of the species. Potential impacts in its introduced European range include disease transmission, hybridization (in Greece with native endemic Aristotle’s catfish [Silurus aristotelis]), predation on native species and possibly the modification of food web structure in some regions. However, S. glanis has also been reported (France, Spain, Turkmenistan) to prey intensively on other non‐native species and in its native Germany to be a poor biomanipulation tool for top‐down predation of zooplanktivorous fishes. As such, S. glanis is unlikely to exert trophic pressure on native fishes except in circumstances where other human impacts are already in force. In summary, virtually all aspects of the environmental biology of introduced S. glanis require further study to determine the potential risks of its introduction to novel environments. 相似文献
12.
The impact of storm water runoff on a small urban stream 总被引：2，自引：0，他引：2
Vilmantė Karlavičienė Sigita Švedienė Danutė Elena Marčiulionienė Peter Randerson Mindaugas Rimeika William Hogland 《Journal of Soils and Sediments》2009,9(1):6-12
Background, aim, and scope In urban areas, storm water runoff often transports various pollutants, some of which settle and form sediments. In order
to have the comprehensive view of the ecological state of storm water runoff recipients, both water and sediments of the stream
must be assessed. In the Baltic Sea Area, the Water Framework Directive & HELCOM Recommendations aim to prevent or minimise
pollution caused by harmful substances arising from storm water runoff, in order to promote the ecological restoration of
the Baltic Sea—one of the most vulnerable seas. The aim of the study was to investigate the toxicity of bottom sediments of
a small storm water runoff recipient focusing on the potential impact of successive discharges of urban storm water. Some
storm water runoff quality parameters and the toxicity of bottom sediments of recipients was studied in this research.
Materials and methods During 9 years, at four discharge points, minimum four grab samples per year at each discharge point were taken for chemical
characterisation. General parameters (pH, SS, BOD7, CODCr and TPH) in liquid phase samples were analysed according to standard methods. Annual limit values were taken from the Lithuanian
EPA requirements for the management of storm water runoff with a focus on prevention and control of contamination. Eleven
composite samples of stream bottom sediments, each consisting of ten sub-samples, were collected in 2006. Toxicity screening
from sediments was performed using the plant Lepidium sativum according to modified I. Magone’s methodology (Magone I, Bioindication of phytotoxicity of transport emission. In: Kachalova
O-L, Zinatne (eds) Bioindication of toxicity of transport emissions in the impact of highway emissions on natural environment. Riga, pp 108–116, 1989). The level of toxic impact of Lepidium sativum (compared to control) was assessed according to the modified method of Wang (Rev Environ Contam Toxicol 126:88–127, 1992).
Results The mean pH of urban storm water runoff does not vary much from neutral, but range values are quite different, from 4.0 up
to 8.7. The highest concentration of SS reached 800 mg L−1, TPH—2.4 mg L−1, BOD7—300 mg O2 L−1 and CODCr—1,400 mg L−1. The SS was above the limit in 64% of total amount of grab samples, TPH—37%, BOD7—41% and CODCr—55%. The toxicity analysis of the bottom sediments showed varying toxicity of bottom sediments along the stream. From nine
analysed samples of bottom sediments, 30% had weak toxicity, 30% medium and 30% strong toxicity on the test organism plant
L. sativum. There was one single sample with no toxic effects, so that the results showed that urban storm water has an unacceptable
environmental impact on recipients. It was also indicated that storm water runoff discharge alone is not the potential source
of toxicity of bottom sediments. The litter demonstrated a weak toxicity of bottom sediments as well.
Discussion Most local authorities do not consider storm water runoff discharges to be a matter of great concern because they believe
that surface runoff arising from rainfall is still relatively clean. The study showed that the current method of monitoring
storm water runoff quality by chemical analyses is not the best tool for environmental impact assessment and must be combined
with toxicity tests of bottom sediments of recipients.
Recommendations and perspectives To avoid the environmental impact of storm water runoff more attention should be paid to the development and implementation
of storm water runoff pollution prevention measures. The study implies that future research concerning the relationships between
storm water runoff deposit characteristics and biological activities must be developed to evaluate the contamination potential
of stream sediment deposits for local aquatic ecosystems. Further studies should be developed to characterise the activities
of the microbial community of storm water runoff sediments, and to monitor bioremediation in situ. 相似文献
13.
14.
Cesonienė L Daubaras R Jasutienė I Venclovienė J Miliauskienė I 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(3):238-244
Benzoic acid, total anthocyanins, soluble solids, titratable acidity, and colour properties in juice of the American cranberry
Vaccinium macrocarpon and the European cranberry Vaccinium oxycoccos were investigated. Berry juices of V. macrocarpon cultivars were distinguished by their higher total anthocyanin and benzoic acid amounts. These cultivars accumulated on average
43.11 mg/l of benzoic acid and 92.45 mg/l of total anthocyanins. The levels of benzoic acid and total anthocyanins in V. oxycoccos cultivars were 17.52 mg/l and 42.54 mg/l, respectively. The V. macrocarpon cultivars ‘Franklin’, ‘Le Munyon’, ‘Searles’, and ‘Early Richard’ were selected as the best according to the enhanced total
anthocyanins and benzoic acid amounts. The separation of anthocyanins by HPLC-UV-VIS revealed the presence of six anthocyanins,
with peonidin-3-galactoside being the most prevalent. Galactoside together with glucoside conjugates comprised the largest
percentage of total anthocyanins in the juices of V. macrocarpon and V. oxycoccos cultivars. 相似文献
15.
Kristina Ložienė 《Industrial Crops and Products》2009,29(2-3):502-508
The high infraspecific chemical and morphological polymorphism is characteristic for species of genus thyme (Thymus L.). This characteristic can be subservient to the selection of valuable clones from natural habitats. The objective of the present study was to select valuable Thyme clones from native flora of Lithuania according to the productivity of biomass and chemical composition of essential oils for the cultivation. Two Thymus species, namely large thyme (T. pulegioides L.) and wild thyme (T. serpyllum L.), grow wild in Lithuania and other Baltic States (Latvia and Estonia). Was established that T. pulegioides is more suitable for the cultivation than T. serpyllum, because can grow more dried total biomass (up to 3 times), are higher (2.8 times) and synthesize higher amount of essential oils with significant amounts of such biologically active compounds as the thymol, carvacrol, geraniol or linalool. Four most fecund clones of T. pulegioides (the total biomass of dried plant 29–45 g, the amount of essential oil in whole plant 0.5–0.7%) were selected which accumulate the highest amounts of thymol (up to 26.1%), carvacrol (up to 31.0%), geraniol (up to 45.0%) and linalool (up to 80.3%). The cultivation of these clones enables to get the high yield of biomass and chemically homogeneous herbal raw material of desirable chemical composition for the phytomedicines and phytocosmetics. 相似文献
16.
Two Rotstop® preparations, one containing a Phlebiopsis gigantea strain from Finland (Rotstop F) and the other one from Sweden (Rotstop S), were used in different concentrations to treat thinning stumps of Picea abies against spore infections by Heterobasidion spp. in southern Sweden. Trees were cut on three sites during the summer of 2004, and 285 stumps were treated manually ensuring 100% coverage. Spore concentrations in the treatment suspensions were ca 5 × 106 and 10 × 106 spores/l, and approximately 10 ml of suspension was applied per 100 cm2 of stump surface. An additional 31 stumps on one of the sites were treated mechanically with Rotstop S; in this treatment the spore concentration was high, about 20 × 106 spores/l, but the coverage was incomplete. Three months later there was a significant reduction in frequency and relative areas of Heterobasidion spp. infections on stumps with manual treatment compared with the untreated stumps. However, there was no significant difference between the preparations or the concentration of active ingredient in terms of their reduction of Heterobasidion infection. Mechanical treatment with incomplete coverage failed to control infection. Therefore, in conditions of moderate Heterobasidion spore load in the environment there seems to be no reason to use higher concentrations of P. gigantea in the treatment of spruce stumps. 相似文献
17.
Aušra Arlauskienė Aleksandras Velykis Alvyra Šlepetienė Dalia Janušauskaitė 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2016,66(8):677-687
ABSTRACTDuring 2008–2011, model field experiments were carried out at the Joni?k?lis Experimental Station of Lithuanian Research Centre for Agriculture and Forestry on a clay loam Endocalcaric Endogleyic Cambisol. The study was aimed to establish the comparison of various postharvest practices (mineral nitrogen fertiliser alone or together with a bioactivator Penergetic k, livestock slurry, red clover biomass and straw incorporation in the soil by a stubble cultivator at a 10 cm depth) on the acceleration of the initial (nine-month period) decomposition of winter wheat straw. During this period, straw mass decomposition intensity was 20.7–29.1%, carbon (C) concentration decreased by 6.5–22.8%, while an increase in nitrogen (N) by 1.1–2.2 times was observed. The highest straw decomposition rate was recorded when after straw incorporation autumn was warm and humid. That year straw mass C to N ratio (C/N) was 38–46. Under less-favourable autumn conditions, the highest decomposition of straw was achieved, having applied mineral N (with and without Penergetic) and livestock slurry and having incorporated the straw in the soil (C/N = 40–55). A slower decomposition rate was observed for the straw spread on the soil surface with mineral N addition or on undersown red clover. 相似文献
18.
Sarkũnas M Malakauskas A Nansen P Hansen JW Paulikas V 《Acta veterinaria Scandinavica》1999,40(2):163-171
The effect of strategic treatments with ivermectin in first-season calves exposed to trichostrongyle nematodes on naturally contaminated pasture was studied. Twenty first season heifer calves were divided into 2 groups, according to live weight, and on 22nd May each group was turned out onto a 1 hectare pasture. Group A (Plot A) was treated with ivermectin at weeks 3, 8 and 13 after turn out, while group B (Plot B) served as an untreated control group. The study showed that control calves exhibited increase in trichostrongyle egg counts in August, while treated calves were excreting low numbers of trichostrongyle eggs. Pasture larval counts on Plot B (control animals) were low during the first part of the grazing season, followed by a steep rise towards the end of July. In contrast, the numbers of infective larvae recovered from Plot A remained low throughout the season. Both groups showed comparable weight gains from May up to the middle of July. However, from then on, Group B (controls) had lower weight gains than ivermectin treated Group A. From the end of July onwards, most untreated calves (Group B) showed clinical signs of parasitic gastroenteritis. It can be concluded that the strategical ivermectin treatments were successful, and faecal egg counts, pepsinogen levels and herbage larval counts clearly demonstrated that this was accomplished through suppression of pasture contamination with nematode eggs and subsequent reduction of pasture infectivity. 相似文献
19.
- 1. Shellfish farming is an expanding segment of marine aquaculture, but environmental effects of this industry are only beginning to be considered.
- 2. The interaction between off‐bottom, suspended oyster farming and wintering sea ducks in coastal British Columbia was studied. Specifically, the habitat use of surf scoters (Melanitta perspicillata) and Barrow's goldeneyes (Bucephala islandica), the most abundant sea duck species in the study area, was evaluated in relation to natural environmental attributes and shellfish aquaculture.
- 3. The extent of shellfish farming was the best‐supported habitat variable explaining variation in surf scoter densities, and the only habitat attribute from the considered set that was a strong predictor of Barrow's goldeneye densities. In both cases, the findings indicated strong positive relationships between densities of sea ducks and shellfish aquaculture operations. These relationships are presumably the result of large numbers of wild mussels (Mytilus trossulus) that settle and grow on aquaculture structures and are preferred prey of these sea ducks.
- 4. Previous work has shown that aquaculture structures provide good conditions for recruiting and growing mussels, including refuge from invertebrate predators, which in turn provides higher densities of higher quality prey for sea ducks than available in intertidal areas. This offers a rare example in which introduction of an industry leads to positive effects on wildlife populations, which is particularly important given persistent declines in numbers of many sea ducks.
20.
Remigijus Ozolinčius Edmundas Lekevičius Vidas Stakėnas Audronė Galvonaitė Arūnas Samas Donatas Valiukas 《European Journal of Forest Research》2014,133(1):51-60
Outputs from the HadCM3 Global Climate Circulation Model according to scenarios A2 and B1 were used for climate change predictions in Lithuania. According to scenario A2, the annual temperature will increase by approximately 4.0 °C from 2061 to 2090, while scenario B1 predicts an increase of 2.0 °C. In contrast to scenario B1, scenario A2 predicts an annual increase in precipitation of 15–20 % at the end of the century. Based on the predicted climatic data for the two scenarios and climate maps by European Food Safety Authority for the EU, we created climate analogues for Lithuania for 2031–2060 and 2061–2090. These areas were overlain by the digital map of native tree species distributions in Europe, which was created from the European Forest Genetic Resources Programme database. If climate changes occur according to scenario B1, in 2031–2060, Lithuania’s climate will become suitable for approximately five to six alien species, such as Acer campestre, Acer pseudoplatanus, Fagus sylvatica, Populus nigra, and Prunus avium. In 2061–2090, these species will be joined by Sorbus domestica and Tilia platyphyllos. If climate changes occur according to scenario A2, at the end of the twenty-first century, Castanea sativa, Quercus pubescens, and Sorbus torminalis could expand this list. With respect to species dispersal rates, there is a high probability that the species A. campestre, A. pseudoplatanus, P. nigra, and P. avium will become immigrants to Lithuanian forests at the end of the twenty-first century. Approximately 20 new species native to Europe will be suitable for cultivation (scenario A2). Climate change will affect the distributions of native species too. An increase in the proportion of deciduous tree species (except Alnus incana) and some reduction in the proportion of conifers, Norway spruce (Picea abies) and Scots pine (Pinus sylvestris), are expected in Lithuanian forests. 相似文献