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Gabrielle Thiébaut - One of the best experts on this subject based on the ideXlab platform.
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Regeneration and colonization abilities of the invasive species Elodea Canadensis and Elodea nuttallii under a salt gradient: implications for freshwater invasibility
Hydrobiologia, 2018Co-Authors: Lise Thouvenot, Gabrielle ThiébautAbstract:Salinity plays an important role in macrophyte distribution. The current increase in salinization of native freshwaters could modify their susceptibility to invasion. In this study, we determined the tolerance to salt of two invasive macrophytes: Elodea Canadensis and Elodea nuttallii. We analysed their growth, regeneration and colonization abilities and the influence of their phenological stage in their response to salt in a laboratory experiment. Traits of both Elodea species varied according to the season and the salt concentration: they were more affected by salt in autumn than in spring, demonstrating higher salt tolerance in spring than in autumn. The two species were sensitive to different thresholds of salinity, although they were both strongly reduced at 3 g l−1 of salt in autumn. Consequently, salt marshes and brackish waters (salt concentration inferior to 3 g l−1 of salt) are likely to be invaded by both species, but the effect of salt levels superior to 3 g l−1 on plant invasiveness needs to be investigated.
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Resistance to herbivory of two populations of Elodea Canadensis Michaux and Elodea nuttallii Planchon St. John
Plant Ecology, 2011Co-Authors: Anatole Boiche, G. Damien Lemoine, Marie-hélène Barrat-segretain, Gabrielle ThiébautAbstract:In this article, we compared the resistance of two introduced populations of Elodea nuttallii and Elodea Canadensis to two different herbivores. Samples were collected from the River Rhine and River Rhone in eastern France. The two populations of E. nuttallii differed in their introduction history, whereas E. Canadensis was introduced at the same time in the two sites. The Daily Food Consumption (DFC) rates of the two macrophyte populations were evaluated in no-choice experiments using the scraper Lymnaea stagnalis and the shredder Gammarus roeseli. At the same time, we assessed four plant traits: dry matter content (DMC), total nitrogen content, carbon/nitrogen ratio and total phenolic content. The two populations of E. Canadensis were consumed at low levels by both the herbivores. L. stagnalis showed a higher DFC on the Rhone population of E. nuttallii than on the Rhine population. No significant difference between the two populations was established with G. roeseli, but the level of DFC was high. This result demonstrates that the assessment of plant palatability should be carried out with several generalist herbivores belonging to various feeding groups (e.g. scrapers or shredders). Although the Rhone population of E. nuttallii had higher levels of phenols than the other populations, it was consistently consumed in greater quantities than E. Canadensis. Neither the phenolic contents were not effective against these herbivores, nor the levels of phenolics too low to induce an efficient resistance. The higher DMC and the lower DFC of the two populations of E. Canadensis suggest that this introduced plant has co-evolved with indigenous enemies in the introduced range.
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Accumulation of metals in Elodea Canadensis and Elodea nuttallii: implications for plant-macroinvertebrate interactions.
The Science of the total environment, 2010Co-Authors: Gabrielle Thiébaut, Y. Gross, Pierre Gierlinski, Anatole BoicheAbstract:Elodea nuttallii and Elodea Canadensis are considered good candidates for metal studies. Metal pollution can disturb the interactions between trophic levels. Our goals were 1) to analyse the metal content in plants, sediment and water from three polluted sites, and 2) to analyse the impact of metal contamination on plant consumption by macroinvertebrates. The concentrations of Cd, Cr, Cu, Mn, Ni, Pb, Zn and Fe and S were measured in water, sediment and in the two Elodea species during two years. Our results showed that metal accumulation varied according to site, metal and season. The ability to uptake metal was similar in E. Canadensis and in E. nuttallii. No significant seasonal metal accumulation was established for plants or sediment. Metal accumulation in Elodea species in polluted sites had no impact on their palatability. The plant palatability depends on the season and varies according to the part of the plant. In autumn, apex was less consumed than defoliated and foliated stems.
L. G. Bondareva - One of the best experts on this subject based on the ideXlab platform.
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Interaction of Tritium with Elodea Canadensis and Lemna minor.
Radiatsionnaia biologiia radioecologiia, 2016Co-Authors: L. G. Bondareva, M A SubbotinAbstract:Tritium is the least toxic radionuclide. The main contribution into the total tritium content in ecosystems is made by technogenic tritium, which is due to the operation of nuclear fuel cycle enterprises. The tritium content in the ecosystem of the River Yenisei is connected with its background values as well as with tritium entering the water ecosystem as a result of the operation of the Mining and Chemical Combine, MCC Rosatom. Presented here are the investigations of the possible transformation of tritium interacting with certain species of aqueous plants - submerged rnacrophyte Elodea Canadensis and an aqueous plant floating on the surface of water reservoirs Lemna minor. Elodea sampling was made in a real water reservoir - the River Yenisei, while lemna was grown in the laboratory conditions. The experiments show that with the chronic exposure of young Elodea shoots to tritium, the latter transforms from HTO to OBT. Optimal conditions were also obtained for the maximum transformation of tritium ≈35% from the total content: at 25°C and the light period 6/18 (day/night). In the experiments with duckweed, observed a significant increase in area of fronds in introducing tritium into the system.
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subcellular localization of 241am in structural components of submerged macrophyte of the river yenisei Elodea Canadensis
International Aquatic Research, 2012Co-Authors: L. G. Bondareva, Olga Mogilnaya, I E VlasovaAbstract:We studied the microdistribution of the artificial radionuclide 241Am in the components of Elodea Canadensis - a submerged macrophyte of the Yenisei River. The alpha-track analysis showed that the microdistribution of 241Am within different components of the submerged plant E. Canadensis was not uniform. 241Am distribution was found to be affected by the age of the leaf blades, state of the cells, and morphological features of the plant stem. The radionuclide 241Am penetrated into the plant cells through the cell wall of E. Canadensis, but it was accumulated in the vacuoles rather than in the cell wall or cytoplasm. In this case, the integrity of the cell membranes was not damaged.
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Accumulation of 242Pu by a macrophyte of the Yenisei River (Elodea Canadensis) in laboratory experiments
Chemosphere, 2009Co-Authors: A. Bolsunovsky, L. G. Bondareva, F. V. Sukhorukov, M. MelgunovAbstract:Abstract The study addresses 242Pu accumulation by Elodea Canadensis, one of the abundant species of submerged plants in the Yenisei River. 242Pu in water samples of the “Elodea – Yenisei River water” model system and in the biomass fractions was determined α-spectrometrically, following radiochemical recovery of 242Pu using 236Pu – a chemical yield tracer. The experiments on accumulation of 242Pu by Elodea biomass showed that the activity concentration of 242Pu can reach 21 ± 2 Bq/g dry wt, with the concentration factor for 242Pu 13100 ± 2100 L/kg dry wt. Results of chemical fractionation proved that during the first few hours of the experiment 242Pu contained in Elodea was mainly concentrated in the exchangeable and the adsorbed fractions of biomass (about 100%). As Elodea biomass accumulated 242Pu, the absolute amount of 242Pu in the exchangeable and the adsorbed fractions remained almost unchanged, although the portion of 242Pu tightly bound to biomass increased. At the end of the experiment, on day 7, 242Pu tightly bound to biomass (fractions of organics and mineral residue) constituted 43–63% (in different experiments) of the total 242Pu in the biomass.
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Accumulation and release of 99Tc by a macrophyte of the Yenisei River (Elodea Canadensis) in laboratory experiments
Journal of Radioanalytical and Nuclear Chemistry, 2008Co-Authors: A. Bolsunovsky, L. G. BondarevaAbstract:The study addresses 99Tc accumulation and release by Elodea Canadensis, one of the abundant species of submerged plants in the Yenisei River 99Tc in water samples of the “Elodea-Yenisei River water” model system and in the biomass fractions was measured using a liquid scintillatio analyzer. Experiments on accumulation of 99Tc by Elodea showed that 99Tc activity concentration can reach 120±6 Bq/g dry wt, with concentration factor for 99Tc 2700±500 l/kg dry wt. In experiments on 99Tc release, over 504 hours about 82% of the total 99Tc activit released into the water from the plant; most of 99Tc was released within the first 192 hours. The data obtained using sequential chemica fractionation of biomass confirmed the experimental data on 99Tc release, which suggested that most of the biomass-bound 99Tc was adsorbed the surface of Elodea. 99Tc tightly bound to biomass (fractions of organics and mineral residue) constituted just 17% of the total 99Tc activity.
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Accumulation and release of 241Am by a macrophyte of the Yenisei River (Elodea Canadensis)
Journal of environmental radioactivity, 2005Co-Authors: A. Bolsunovsky, T. A. Zotina, L. G. BondarevaAbstract:Abstract The source of radioactive contamination of the Yenisei River floodplain, including contamination with transuranic elements, is the Mining-and-Chemical Combine of the Russian Ministry of Atomic Energy, which has for many years been producing weapons-grade plutonium. Transuranic elements have been detected not only in the soil and sediment of the river but also in the biomass of aquatic plants. This work is an investigation of accumulation and release of 241 Am by a submerged macrophyte of the Yenisei River ( Elodea Canadensis ) in laboratory experiments. In 2000–2003, laboratory experiments were carried out with biomass of E. Canadensis Mich. and filtered river water. The samples were collected from the Yenisei River upstream of the discharge of the Combine's radioactive effluent. The experiments showed that 241 Am is accumulated by Elodea biomass: the activity concentration of 241 Am can reach 3280 ± 240 Bq/g, with the concentration factor for 241 Am 16 600 ± 2200 l/kg. Results of chemical fractionation have proved that in the course of 241 Am accumulation by Elodea biomass, 241 Am tightly bound to biomass increases from 11% to 27% of the total 241 Am in the biomass. Release of 241 Am from the decaying Elodea biomass has been evaluated experimentally. By the end of the experiment (lasting up to 127 days), the Elodea plants had lost up to 65% of their initial 241 Am activity and the rate of 241 Am release into the water environment reached 23 Bq/day.
Mika A. Kähkönen - One of the best experts on this subject based on the ideXlab platform.
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The uptake of nickel and chromium from water by Elodea Canadensis at different nickel and chromium exposure levels
Chemosphere, 1998Co-Authors: Mika A. Kähkönen, Pentti K.g. ManninenAbstract:The uptake of Ni and Cr from water was studied at three Ni and Cr exposure levels in a laboratory by cosmopolitan submerged macrophyte, Elodea Canadensis Mixch. The uptake late of Ni and Cr diminished, when the exposure time came longer and the initial concentration was lower. The uptake of Ni by Elodea Canadensis was 25 to 40 times higher than the uptake of Cr in the same initial concentration. After 24 hours Elodea Canadensis accumulated rather high content of Ni (310 – 2150) μg/DWg and a much lower amount of Cr (8 – 84) μg/DWg.
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The effects of nickel on the nutrient fluxes and on the growth of Elodea Canadensis
Chemosphere, 1998Co-Authors: Mika A. Kähkönen, Timo KairesaloAbstract:Abstract In the through-flow method was measured the effect of Ni exposure on the net uptake and/or release of phosphorus and nitrogen and on the growth of submerged macrophyte, Elodea Canadensis Michx. These results showed that Ni clearly inhibited the nutrient metabolism of Elodea at all exposure levels, from 70 up to 1700 μmol dm−3. The nutrient metabolism was more sensitive and earlier response than the growth of the test plants.
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analysing heavy metal concentrations in the different parts of Elodea Canadensis and surface sediment with pca in two boreal lakes in southern finland
Chemosphere, 1997Co-Authors: Mika A. Kähkönen, Mari Pantsarkallio, Pentti K.g. ManninenAbstract:The concentrations of six heavy metals (Fe, Mn, Cu, Zn, Ni, Cr) were studied in the roots, shoots and leaves of Elodea Canadensis and in the surface sediment collected in four different parts in the eutrophic L. Vesijarvi and in the oligotrophic L. Paajarvi in Southern Finland. Principal component analysis was performed on the data set. The heavy metal concentrations of Elodea Canadensis depend on the part of the plant and do not indicate the heavy metal concentrations in the growing place. Elodea Canadensis accumulates Fe and Cu in the roots and Ni, Mn and Cr in the leaves. The concentrations of these five metals were lowest in the shoots, indicating the uptake route and transport of these metals in the macrophyte. Zn is mobile in Elodea Canadensis, since it's concentration was nearly as high in the roots, shoots and leaves. The order of Cr, Ni, Cu, Zn and Fe concentrations in the sediment were the same between different sampling places. Only Mn differed slightly from this order.
T. A. Zotina - One of the best experts on this subject based on the ideXlab platform.
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chromosomal abnormalities in roots of aquatic plant Elodea Canadensis as a tool for testing genotoxicity of bottom sediments
Ecotoxicology and Environmental Safety, 2015Co-Authors: T. A. Zotina, D. V. Dementyev, E. A. Trofimova, Marina Yu Medvedeva, Yuliyana Alexandrova, Alexander Ya. BolsunovskyAbstract:Submersed freshwater macrophytes are considered as relevant indicators for use in bulk bottom sediment contact tests. The purpose of this study was to estimate the validity of endpoints of aquatic plant Elodea Canadensis for laboratory genotoxicity testing of natural bottom sediments. The inherent level of chromosome abnormalities (on artificial sediments) in roots of E. Canadensis under laboratory conditions was lower than the percentage of abnormal cells in bulk sediments from the Yenisei River. The percentage of abnormal cells in roots of E. Canadensis was more sensitive to the presence of genotoxic agents in laboratory contact tests than in the natural population of the plant. The spectra of chromosomal abnormalities that occur in roots of E. Canadensis under natural conditions in the Yenisei River and in laboratory contact tests on the bulk bottom sediments from the Yenisei River were similar. Hence, chromosome abnormalities in roots of E. Canadensis can be used as a relevant and sensitive genotoxicity endpoint in bottom sediment-contact tests.
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use of the aquatic plant Elodea Canadensis to assess toxicity and genotoxicity of yenisei river sediments
Environmental Toxicology and Chemistry, 2015Co-Authors: T. A. Zotina, E. A. Trofimova, D. V. Dementyev, Marina Yu Medvedeva, Alexander Ya. BolsunovskyAbstract:The toxicity, cytotoxicity, and genotoxicity of bulk sediments from the Yenisei River (Siberia, Russia) were estimated in laboratory bioassays based on several endpoints in the aquatic plant Elodea Canadensis. The bottom sediment samples were collected in the Yenisei River upstream and downstream of the sources of chemical and radioactive contamination. The testing revealed different sensitivities of Elodea endpoints to the quality of the bottom sediment: weight of shoots < length of shoots < mitotic index < length of roots < percentage of abnormal cells. The response of the genotoxicity endpoint (percentage of cells with chromosome abnormalities in roots of Elodea) was the highest in sediments with chemical pollution, whereas the highest inhibition of toxicity endpoints (shoot and root length) occurred in sediments with the highest level of radioactive pollution. The extreme response of Elodea endpoints to the quality of certain sediment samples may be regarded as related to the possible presence of unknown toxicants. The results show that E. Canadensis can be used as an indicator species in laboratory contact testing of bottom sediment. The responses of shoot and root length growth endpoints of Elodea can be recommended as basic sensitivity indicators of bottom sediment toxicity. Analysis of cells carrying abnormal chromosomes in the apical root meristem of Elodea can be performed optionally in the same test to assess the genotoxicity of sediments. Environ Toxicol Chem 2015;34:2310–2321. © 2015 SETAC
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Cytogenetic abnormalities in aquatic plant Elodea Canadensis in anthropogenic contamination zone of Yenisei River
Contemporary Problems of Ecology, 2014Co-Authors: M. Yu. Medvedeva, A. Ya. Bolsunovsky, T. A. ZotinaAbstract:Chromosome abnormalities in ana-telophase cells of apical root meristem of aquatic plant Elodea. Canadensis (Elodea), sampled in 2011–2012 in the Yenisei River at a site with background level of contamination and at several sites on the stretch contaminated with artificial radionuclides, and with chemical pollutants from municipal and industrial discharges of the Krasnoyarsk city. Lowest rate (5.2%) of cells with chromosome abnormalities was registered at sampling site with background level of contamination upstream of the Krasnoyarsk, highest rate of cells with abnormalities (39.7%)—in roots of Elodea sampled in bottom sediments with highest concentration of 137Cs. Sum of rates of cells with abnormalities and rates of cells with all types of abnormalities positively correlated with total concentration of artificial and natural radionuclides, with concentration of artificial radionuclides and 137Cs in bottom sediments of the Yenisei River (r2 = 0.91–0.96, p < 0.0005 for sum of rates of cells with abnormalities; r2 = 0.58–0.92, p < 0.05 for all types of abnormalities).
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accumulation and distribution of 241am in the biomass of freshwater plant Elodea Canadensis
Radioprotection, 2009Co-Authors: T. A. Zotina, Galina S Kalachova, Ya A BolsunovskyAbstract:Accumulation of transuranic element 241 Am by photoassimilating organs and its distribution in fractions of the biomass of aquatic plant Elodea Canadensis have been investigated in laboratory batch experiments. Americium was taken up by apical shoots of Elodea from water. Of the activity accumulated by the shoots, up to 80% of 241 Am was detected in the leaves and 20% in the stems. Americium concentration in apical leaves was several times higher than in distal leaves. Of the 241 Am activity concentrated in the shoots, 95% was bound to cell walls, membranes and organelles and 5% of the radionuclide was dissolved in cytoplasm. Less than 1% of americium accumulated in the biomass was found in the lipid extract; up to 10% of americium was bound to proteins and carbohydrates; the major part of the radionuclide (about 90%) was registered in the cell wall fraction that mainly contained cellulose-like polysaccharides. Biomass treatment with hydrochloric acid resulted in desorption of about 70% of americium, mostly from the polysaccharides.
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Accumulation and release of 241Am by a macrophyte of the Yenisei River (Elodea Canadensis)
Journal of environmental radioactivity, 2005Co-Authors: A. Bolsunovsky, T. A. Zotina, L. G. BondarevaAbstract:Abstract The source of radioactive contamination of the Yenisei River floodplain, including contamination with transuranic elements, is the Mining-and-Chemical Combine of the Russian Ministry of Atomic Energy, which has for many years been producing weapons-grade plutonium. Transuranic elements have been detected not only in the soil and sediment of the river but also in the biomass of aquatic plants. This work is an investigation of accumulation and release of 241 Am by a submerged macrophyte of the Yenisei River ( Elodea Canadensis ) in laboratory experiments. In 2000–2003, laboratory experiments were carried out with biomass of E. Canadensis Mich. and filtered river water. The samples were collected from the Yenisei River upstream of the discharge of the Combine's radioactive effluent. The experiments showed that 241 Am is accumulated by Elodea biomass: the activity concentration of 241 Am can reach 3280 ± 240 Bq/g, with the concentration factor for 241 Am 16 600 ± 2200 l/kg. Results of chemical fractionation have proved that in the course of 241 Am accumulation by Elodea biomass, 241 Am tightly bound to biomass increases from 11% to 27% of the total 241 Am in the biomass. Release of 241 Am from the decaying Elodea biomass has been evaluated experimentally. By the end of the experiment (lasting up to 127 days), the Elodea plants had lost up to 65% of their initial 241 Am activity and the rate of 241 Am release into the water environment reached 23 Bq/day.
Maria Greger - One of the best experts on this subject based on the ideXlab platform.
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cadmium uptake in Elodea Canadensis leaves and its interference with extra and intra cellular ph
Plant Biology, 2014Co-Authors: M T Javed, Sylvia Lindberg, Maria GregerAbstract:This study investigated cadmium (Cd) uptake in Elodea Canadensis shoots under different photosynthetic conditions, and its effects on internal (cytosolic) and external pH. The plants were grown und ...
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Cellular proton dynamics in Elodea Canadensis leaves induced by cadmium.
Plant physiology and biochemistry : PPB, 2014Co-Authors: M. Tariq Javed, Sylvia Lindberg, Maria GregerAbstract:Our earlier investigations showed that Elodea Canadensis shoots, grown in the presence of cadmium (Cd), caused basification of the surrounding medium. The present study was aimed to examine the pro ...
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Cadmium triggers Elodea Canadensis to change the surrounding water pH and thereby Cd uptake.
International journal of phytoremediation, 2010Co-Authors: M. Tariq Javed, Maria GregerAbstract:This study was aimed to investigate the influence of Elodea Canadensis shoots on surrounding water pH in the presence of cadmium and the effect of plant-induced pH on cadmium uptake. The pH change in the surrounding nutrient solution and Cd uptake by Elodea shoots were investigated after cultivation of various plant densities (1, 3, 6 plants per 500 ml) in hydroponics at a starting pH of 4.0 and in the presence of different concentrations of cadmium (0, 0.1, 0.5 microM). Cadmium uptake was also investigated at different constant pH (4.0, 4.5, 5.5 and 6.5). To investigate if the pH change arose from photosynthetic activities, plants were grown under light, darkness or in the presence of a photosynthetic inhibitor, 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), and 0.5 microM cadmium in the solution. Elodea had an ability to increase the surrounding water pH, when the initial pH was low, which resulted in increased accumulation of Cd. The higher the plant density, the more pronounced was the pH change. The pH increase was not due to the photosynthetic activity since the pH rise was more pronounced under darkness and in the presence of DCMU. The pH increase by Elodea was triggered by cadmium.
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uptake of zn cu and cd in metal loaded Elodea Canadensis
Environmental and Experimental Botany, 2007Co-Authors: Johanna Nyquist, Maria GregerAbstract:Since uptake of metals in submerged plants can have a positive effect on the total remediation efficiency in a wetland it is important to investigate factors that possibly can have an effect on uptake of metals. In this short term study we investigated whether the tissue concentration of Zn, Cu and Cd influenced further uptake by metals in Elodea Canadensis. Stress effects in response to metal exposure were also investigated. Plants were first loaded with metals for 48 h followed by a metal exposure period of 72 h. Metals in plant tissue and stress effects on plants were analysed both prior to, and after exposure. The results showed that tissue concentration of Zn and Cu did not have effect on further uptake, however for Cd it did have an effect. During Cd exposure accumulated Cd started to leak out of the plants where a decreased leakage could be seen with increased exposure concentration of Cd. The degree of metals binding to the cell wall could explain the influence of tissue concentration on uptake. These results are relevant to the phytoremediation technology area, where it is of great importance to achieve knowledge of commonly used plant species in treatment wetlands to optimise treatment of polluted areas.
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Fate of cadmium in Elodea Canadensis.
Chemosphere, 2006Co-Authors: Åsa Fritioff, Maria GregerAbstract:Elodea Canadensis is a submersed macrophytes, widely distributed in stormwater treatment ponds and able to remove heavy metals from water. This study examines the Cd uptake, translocation, and effl ...