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1
Reels, Graham Thomas. "Management strategies for the reed Phragmites australis (CAV.) Steud. at Mai Po Marshes Nature Reserve, Hong Kong, with observations on the associated insect Fauna /." Hong Kong : University of Hong Kong, 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20665799.
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Neubert, Karin. "Diversität der Schilf (Phragmites australis) assoziierten Mycoflora /." Konstanz, 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=97944747X.
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Colville, Sonia University of Ballarat. "Community response to shading a Phragmites australis reedbed." University of Ballarat, 2005. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/12753.
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The consequences of introducing riparian shade on in-stream community structure has not been well explored in south-eastern Australia. With catchment managers focusing on revegetation of riparian zones, there is a need to understand, monitor, and predict changes in ecological patters and processes that may take place as a system shifts from an open to a shaded stream community. Presented in this thesis is a conceptual model portraying possible responses of a macrophyte community to light reduction as a result of the introduction of riparian vegetation. This model was tested in the field by artificially shading sites (three shade treatments) to observe the direct effects of light reduction on Phragmites australis growth and structure and flow-on effects to associated in-stream biota."Doctor of Philosphy
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Zawawi, Mouafaq Abbas. "Biology of Phragmites australis (Cav.) Trin. ex Steudel." Thesis, Bangor University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315009.
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Armstrong, Jean. "Pathways and mechanisms of aeration in Phragmites australis." Thesis, University of Hull, 1992. http://hydra.hull.ac.uk/resources/hull:11839.
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This thesis describes an investigation into the aeration pathways, resistances to gas-movement, mechanisms of internal aeration and the locations and quantities of oxygen efflux from the underground parts of the common reed Phragmites australis. The "ventilating pressure concept" was also tested and reappraised. Well-developed interconnecting gas-spaces within the culm, rhizome and roots offered relatively small resistance to either diffusive or convective gas transport, and the porosity of root-rhizome junctions was unusually high. Radial channels located at the nodes proved to be the only connecting points between cortex and pith in culms and rhizomes. Rhizome and old adventitious root surfaces were impermeable to oxygen but the young parts of adventitious roots and the numerous laterals readily released oxygen to anaerobic agar media and soil, markedly raising the redox potential of the rhizosphere. It was discovered that callus readily forms in Phragmites in response to wounding and senescence, blocking the gas-spaces of root-rhizome junctions, leaf-sheath-culm junctions, and rhizome nodal diaphragms. However, the culm-rhizome junctions normally remain callus-free despite senescence of the culms, and gaseous connexion between the underground parts and the atmosphere is thus maintained thoughout the year. A major discovery was that pressurised gas-flows are an important feature in Phragmites' aeration: Venturi- and/or Humidity-induced convections produced much higher rhizome oxygen concentrations and radial oxygen loss from the roots than when rhizome aeration was chiefly diffusive. Both experiments and mathematical modelling demonstrated that comparatively slow rates of convection are sufficient to achieve this. The humidity-induced convection, the first reported in a grass, was shown to be initiated chiefly in living leaf sheaths, the convected gases being transmitted via gas-spaces in the culm to those of the underground rhizome, and vented via old broken culms. The flows are particularly rapid at low atmospheric humidities and increase with increasing PAR. The major mechanism promoting the convection appears to be a humidity- induced diffusion or transitional Knudsen diffusion of atmospheric gases into the plant, the concentration gradient being maintained by the difference in humidity between the interior of the plant and the outer air. The process was mimicked and further investigated using Nuclepore membranes providing important insights into the mechanism and its modelling, and it was shown that pore diameters within the Knudsen regime are not essential to produce the static pressure differentials and convective flows found in Phragmites. The Venturi-induced convection, the first reported example in a plant, is created by the action of winds blowing across tall, dead, broken culms; air is drawn into the rhizome system via short broken culms in more sheltered positions. Mathematical models and polarographic measurements of radial oxygen loss from roots were used to estimate the quantities of oxygen which might be released by Phragmites in the root-zone process of sewage treatment. It was concluded that 5 to 12 g 02 m⁻² day⁻¹ would be a conservative estimate but that the amount could be greater or less depending upon root numbers and their physiological condition, as well as upon soil oxygen demand and diffusivities.
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Martins, Patrícia Tavares. "Decomposição in situ de Phragmites australis: comunidades bacterianas." Master's thesis, Universidade de Aveiro, 2009. http://hdl.handle.net/10773/885.
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Mestrado em Biologia MarinhaA utilização de sacos de folhas submersos em estudos de decomposição é um método frequentemente utilizado para estudar ecossistemas de água doce. Usualmente recorre-se ao calculo da taxa de decomposição das folhas, ao padrão temporal das comunidades de macroinvertebrados e à colonização das comunidades microbianas, uma vez que durante a degradação das folhas ocorre uma sucessão de organismos, que reflecte um ajustamento das comunidades biológicas do ambiente envolvente. Neste trabalho pretende-se estudar as comunidades bacterianas que colonizam as folhas de Phragmites australis colocadas em sacos submersos num estuário e recolhidas após 3, 7, 15, 30 e 60 dias de submersão. O trabalho decorreu no canal de Mira, na Ria de Aveiro, onde foram definidas 3 áreas de amostragem (A, C e E). As comunidades bacterianas foram analisadas recorrendo a métodos moleculares, nomeadamente através da electroforese em gel com gradiente desnaturante (DGGE). Neste trabalho foi possível observar que as comunidades bacterianas colonizadoras das folhas são distintas em cada dia em todas as estações de amostragem, com excepção do 15º dia. Junto à embocadura do estuário (zona A) as comunidades bacterianas são idênticas apenas no 3º e 7º dia, apresentando diferenças significativas entre os restantes tempos de amostragem. Na região mediana do estuário (zona C) verifica-se que a comunidade bacteriana no 15º, 30º e 60º dias de amostragem não apresentam diferenças significativas, ao contrário do dia 3 e 7. No topo da região estuarina, em ambiente dulçaquicola (zona E), não foi possível analisar o 60º dia de amostragem, porém observa-se uma separação entre os dois primeiros dias de amostragem (3º e 7º) e os dois últimos (15º e 30º) nas comunidades bacterianas. Pela análise do número de ribotipos, verificou-se que apenas no 3º dia existem diferenças significativas entre as três zonas de amostragem e, no 60ºdia a zona C e E também são significativamente diferentes. Nos restantes dias o número de ribotipos é semelhante em todas as zonas. Foi ainda possível verificar que para a zona A e a zona E, não existem diferenças significativas no número de ribótipos ao longo do tempo, ao contrário do que acontece na zona C, onde ocorre um aumento gradual do número de ribotipos ao longo do tempo. ABSTRACT: The use of leaf-bags to study leaf litter decomposition is a method often used in freshwater ecosystems. Usually these studies use the rate of leaf decomposition, the temporal pattern of macroinvertebrate communities and colonization of microbial communities, because during the leaves breakdown a succession of organisms occurs, which reflects an adjustment of the biological communities in the surrounding environment. The aim of this work was to study the bacterial communities that colonize Phragmites australis leaves in the litter bags, in an estuary, after 3, 7, 15, 30 and 60 days of submersion. The work took place in Mira channel, in Ria de Aveiro, where 3 sampling sites were established along a salinity gradient. Bacterial communities were analyzed using molecular methods, namely by denaturing gradient gel electrophoresis (DGGE). In this study it was observed that the bacterial communities that colonize the leaves submerged in Ria de Aveiro are different at all sampling sites on each day, except the 15th. At the mouth of the estuary (site A), the bacterial communities are identical in the 3rd and 7th day, showing significant differences between the remaining sampling times. In the middle estuary (site C) the bacterial community in the 15th, 30th and 60th day did not differ significantly, unlike at days 3 and 7. At the head of estuary, in freshwater (site E), it was not possible to analyze the day 60, but there was a separation in the bacterial communities between the first two days of sampling (3 and 7) and the last two (15 and 30). The analysis of the number of ribotypes, showed that there are significant differences between the three sampling areas only in the 3rd day. In day 60 sites C and E are significantly different. In the remaining days the number of ribotypes is similar in all sites. It was also possible to see that for sites A and E, there are no significant differences in the number of ribotypes over time, contrary to what happened in site C, where there was a gradual increase in the number of ribotypes over time.
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Colville, Sonia. "Community response to shading a Phragmites australis reedbed." Thesis, University of Ballarat, 2005. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/54866.
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The consequences of introducing riparian shade on in-stream community structure has not been well explored in south-eastern Australia. With catchment managers focusing on revegetation of riparian zones, there is a need to understand, monitor, and predict changes in ecological patters and processes that may take place as a system shifts from an open to a shaded stream community. Presented in this thesis is a conceptual model portraying possible responses of a macrophyte community to light reduction as a result of the introduction of riparian vegetation. This model was tested in the field by artificially shading sites (three shade treatments) to observe the direct effects of light reduction on Phragmites australis growth and structure and flow-on effects to associated in-stream biota."Doctor of Philosphy
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Colville, Sonia. "Community response to shading a Phragmites australis reedbed." University of Ballarat, 2005. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/14592.
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The consequences of introducing riparian shade on in-stream community structure has not been well explored in south-eastern Australia. With catchment managers focusing on revegetation of riparian zones, there is a need to understand, monitor, and predict changes in ecological patters and processes that may take place as a system shifts from an open to a shaded stream community. Presented in this thesis is a conceptual model portraying possible responses of a macrophyte community to light reduction as a result of the introduction of riparian vegetation. This model was tested in the field by artificially shading sites (three shade treatments) to observe the direct effects of light reduction on Phragmites australis growth and structure and flow-on effects to associated in-stream biota."Doctor of Philosphy
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Ritterbusch, David. "Wachstum und Habitatbesetzung von Schilf (Phragmites australis) in Karpfenteichen." [S.l. : s.n.], 2004. http://www.diss.fu-berlin.de/2004/147/index.html.
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Afreen-Zobayed, Fawzia. "Factors affecting the aeration and survival of Phragmites australis." Thesis, University of Hull, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337243.
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Cook, Cassandra. "Impacts of Invasive Phragmites Australis on Diamondback Terrapin Nesting." W&M ScholarWorks, 2016. https://scholarworks.wm.edu/etd/1477068338.
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The diamondback terrapin (Malaclemys terrapin) is a species of turtle found exclusively in brackish water habitats. Terrapins are currently facing population threats including by-catch mortality in crab pots, predation, and habitat loss. The expansion of the exotic, invasive reed Phragmites australis is causing widespread structural and functional changes to coastal ecosystems throughout North America, which could negatively impact the nesting success of female terrapins by invading preferred nesting habitats. I examined the extent to which Phragmites affects nesting of a breeding population of diamondback terrapins at Fisherman Island National Wildlife Refuge on the eastern shore of Virginia, where Phragmites has recently expanded into known areas of terrapin nesting. With data collected from the 2015 nesting season I quantified the impacts of this expansion on terrapin nesting by: determining the extent to which nest incubation temperature is impacted by Phragmites shading, determining how Phragmites density impacts the risk of rhizome invasion into nests, and determining how the presence of Phragmites impacts predation of terrapin nests. I also examined landscape features to determine which factors may be associated with diamondback terrapin nest site use. I found that Phragmites cover greater than 50% would decrease incubation temperatures of terrapin nests sufficiently to produce predominantly male hatchlings. There was no effect of Phragmites cover on root growth into simulated nests, but cover by other dune plant species explained observed trends in root growth. I did not find a significant effect of Phragmites on nest predator activity, but did find that Phragmites had an impact on terrapin nest site use on Fisherman Island. Distance from nest to nearest marsh and tidal creek also influenced terrapin nest site use. With crab pots and roadways contributing to high adult mortality every year, high nesting success will be highly important to maintaining and propagating this charismatic species.
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Davies, Lorna Annette. "The low cost treatment of landfill leachate using constructed wetlands." Thesis, University of Leeds, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275678.
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Zemlin, Rüdiger. "Untersuchungen zur genotypischen und phänotypischen Variabilität verschiedener Schilfklone (Phragmites australis)." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=974370223.
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Zemlin, Rüdiger. "Untersuchungen zur genotypischen und phänotypischen Variabilität verschiedener Schilfklone (Phragmites australis)." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2004. http://dx.doi.org/10.18452/15213.
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In der vorliegenden Arbeit werden Wachstum und Entwicklung von 10 Schilfklonen (Phragmites australis) verglichen, um die genotypische Determinierung verschiedener Eigenschaften sowie den Einfluss der Standortfaktoren auf diese Eigenschaften zu untersuchen. Dabei sollen Aussagen zum Bestehen unterschiedlicher Ökotypen beim Schilf abgeleitet werden. Die Untersuchungen erfolgten auf sechs Pflanzfeldern, die im Rahmen von Renaturierungsmaßnahmen an den Ufern der Berliner Gewässer Seddinsee, Langer See und Havel im Frühjahr 1995 angelegt wurden. Die Anpflanzung erfolgt am Land, das Schilf wuchs in das Wasser vor. Die Herkunftsorte der Schilfklone unterschieden sich in der Nährstoffversorgung, der Substratqualität und der Exposition. Die Ergebnisse ließen deutliche Unterschiede in der Morphometrie der Halme (Halmlänge, Halmdurchmesser, Blattfläche pro Halm), der Halmbiomasse und der Balance zwischen Halmdichten und Halmlängen (bzw. Trockenmassen) zwischen den einzelnen Schilfklonen erkennen. Da dies beim Wachstum unter vergleichbaren Standortbedingungen gefunden wurde, kann eine genotypische Determinierung dieser Eigenschaften vermutet werden. Es konnte ebenfalls ein starker Einfluss der Umwelt auf das Wachstum des Schilfs festgestellt werden. Allgemein waren die Wachstumsbedingungen im Wasser deutlich besser als am Land. Die höchsten Halmbiomassen der einzelnen Schilfklone wurden daher im Wasser erreicht (zwischen 0,7 und 2,1 kg Trockenmasse pro m²), während die Werte am Land geringer waren (zwischen 0,6 und 1,0 kg/m²). Obwohl sich die Schilfklone an ihren ursprünglichen Standorten deutlich in den Stickstoffgehalten der Halme unterschieden, ergaben sich auf den Pflanzungen keine Unterschiede zwischen ihnen. Im Gegensatz dazu lagen die N-Werte bei jedem Schilfklon im Wasser erheblich höher als am Land. Dies lässt folgern, dass die Stickstoffgehalte der Halme in erster Linie vom Stickstoff-Angebot am jeweiligen Standort abhängen. Insgesamt deuten die Ergebnisse darauf hin, dass die Schilfklone genotypische Unterschiede in verschiedenen Merkmalen aufweisen können. Eine mögliche Nutzung zu einer Verbesserung des Erfolges von Pflanzmaßnahmen wird diskutiert.In this study, growth and development of 10 reed clones (Phragmites australis) were compared to investigate genetically determined differences in various characteristics as well as the influence of site conditions on these characteristics. In addition, conclusions on the existence of different ecotypes were to be drawn. The study was performed on six experimental fields, established for shore renaturation on the lakes Seddinsee, Langer See and on the river Havel in Berlin in spring 1995. The plantations were established ashore, the reed expanded into the water. The sites of origin of the clones differed in nutrient supply, substrate quality and shore exposition. The results showed distinct differences between the individual reed clones regarding the morphometrics of the shoots (shoot length, culm diameter, leaf area per shoot), standing crop and the trade-off between shoot length (or dry matter) and shoot density. The fact that these results were found with clones that had grown under comparable site conditions seems to suggest a genotypic determination of these characteristics. A strong influence of the environment on the growth of the reed could also be deserved. In general, the conditions for growth were better in water than ashore. The highest standing crops of the individual reed clones were reached in water (between 0.7 and 2.1 kg drymatter pro m²), while the values ashore were lower (between 0.6 and 1.0 kg/m²). Although the reed clones at their original sites were clearly different in the nitrogen content of shoots, no differences were observed on the experimental fields. In contrast, the N-values of each clone were higher in water than ashore. This suggests that the nitrogen content of the shoots depends primarily on the nitrogen availability at the specific site. The results overall suggest that reed clones could exhibit genetically determined differences in various characteristics. A possible practical use to increase the efficiency of further reed plantations is discussed.
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Ater, Mohamed. "Variations et fertilité du pollen dans le complexe polyploïde du roseau Phragmites australis (Cav. ) Trin. Ex Steud." Paris 11, 1985. http://www.theses.fr/1985PA112150.
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Ce travail présente d’une part un essai d’appréciation de la variabilité s’exprimant au niveau du gamétophyte mâle et d’autre part une approche préliminaire de la biologie de reproduction de l’espèce. La manifestation de la variabilité du gamétophyte mâle a été mise en évidence par des études biométriques du diamètre pollinique (avec une étude détaillée de la variabilité intra-individuelle), de la stéréostructure des surfaces tectales et de la composition minérale de l’exine. Les résultats obtenus confirment la grande hétérozygotie de ce complexe polyploïde. Sur le plan de la biologie de reproduction, ce travail permet de préciser les rapports des reproductions sexuée et asexuée, l’une et l’autre constituant un modèle très complexe dans lequel la multiplication végétative serait associée à des formes adaptatives très évoluées favorisant l’allogamie.
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Reels, Graham Thomas. "Management strategies for the reed Phragmites australis (CAV.) Steud. at Mai Po Marshes Nature Reserve, Hong Kong, with observations on theassociated insect Fauna." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31211835.
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Rothman, Erin K. "Phragmites australis in a freshwater coastal wetland : implications for carbon dynamics." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1194565332.
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Clements, Deborah A. V. "The ecology of stem boring wainscot moths in Phragmites australis reedbeds." Thesis, Anglia Ruskin University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325399.
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Al, Akeel Khaled. "Empirical investigation of water pollution control through use of Phragmites australis." Thesis, Brunel University, 2013. http://bura.brunel.ac.uk/handle/2438/7498.
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This research study addresses a problem of water pollution caused by heavy and toxic metals Cd, Cr, Cu and Pb. The thesis proposes the use of the technique of phytoremediation using Phragmites australis (PA) plants that have the capacity to absorb and to accumulate such metals in their roots and leaves. The metal uptake and their location of accumulation in the PA plants were determined using flame atomic absorption spectroscopy (FAAS) and transmission electron microscopy (TEM) respectively. Leachates from contaminated plant biomass were mixed with silver nitrate to assess the manufacture of metal nanoparticles as an added value step in the process from remediation to biomass disposal. Silver nanoparticles were readily manufactured by the leachates without, with the exception of copper, any incorporation of the pollutant metal. The presence of copper in the manufactured silver nanoparticles may be of some commercial use. The results obtained show that PA plants will accumulate toxic metals when in hydroponic culture and that the majority of the accumulated metals are sequestered in the roots and do not enter the aerial parts of the plants in significant amounts. Silver nanoparticles were manufactured from the biomass using a low energy route with no additional chemicals, apart from silver nitrate thus reducing the environmental load that would otherwise be present if a chemical means of nanoparticle production was used.
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Lambert, Adam Matthew. "Native and exotic Phragmites australis in Rhode Island : distribution and differential resistance to insect herbivores /." View online ; access limited to URI, 2005. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3186908.
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Güsewell, Sabine. "Evaluation and management of fen meadows invaded by common reed (Phragmites australis) /." Zürich, 1997. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=12428.
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Wang, Weiqing. "Fe plaque assisted aquatic U rhizofiltration by Phragmites australis Trin ex Steud. –." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-231406.
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The macrophytes have the ability accumulating multiple metals/metalloids species from the terrestrial and aquatic environments. The environmental-friendly phytoremediation technologies via these plant species have been applied for non-degradable pollutants removal. The macrophytes derived rhizofiltration is a major and efficient technology for metals/metalloids removal, especially in aquatic environments (e.g. wetland).
Comparing with the common metals/metalloids often studied, aquatic U rhizofiltration via macrophytes has been just considered recently. In this study, the field investigation in a U tailing basin wetland showed that the rhizofiltration was crucial for aquatic U retention via Phragmites australis Trin ex Steud. (water to root bioconcentration factor (BCF): 670 to 1556). The aquatic U retention efficiency in aboveground biomass of P. australis was insufficient (BCF: 0.4 to 5.3), comparing with the rhizofiltration. However, the high productivity (1.2 to 1.9 kg•m-2 per growing season) of P. australis still resulted in a notable yearly U accumulation in the areal total aboveground biomass (0.04 to 0.35 mg•m-2 per growing season). It was potentially promoted by the enhanced aquatic U rhizofiltration. The U within aboveground biomass could be released to submerse soil with the degradable or recalcitrant fallen litters. It enhanced the organic carbon supply in rhizosphere together with the root litter, and potential water to root U translocation within mobilized organic compounds. Hence the rhizofiltration stood in the crucial position of the plant-litter-water-soil U recycling in aquatic environment.
The results from field investigation and mesocosm experiment further suggested that the Fe plaque (IP) on root surface was crucial for aquatic U rhizofiltration. The IP contained most of root retained U in both environments (proportion of U within IP: 55.8 to 82.6% in field and 66.7 to 86.0% in mesocosm). However, the efficiency of IP assisted aquatic U rhizofiltration was affected by the redox state gradient (-179 to 220 mV) related redox processes. Field investigation suggested that high content of dissolved oxygen (up to 8.2 mg•l-1) was capable to rapidly oxidize soluble Fe(II) as sparingly soluble Fe(III) oxides precipitated in subhydric soil. It consequently limited the aquatic Fe availability for root uptake and precipitation as IP. However, the strong oxidation ability also relatively increased aquatic U(VI) availability incorporated with inorganics and degradable organic matters. It was adverse for controlling the aquatic U concentration (66.7 to 92.0 μg•l-1 in field). On the other hand, it also benefited the U uptake by inner root tissue and upward translocation to aboveground biomass of P. australis.
The different inorganic N species also significantly influenced IP assisted aquatic U rhizofiltration. The aquatic NH4+ sustained the reduction and acidification (via nitirification) potential for Fe(III) and U(VI) bioreduction in rhizosphere (-87 to 21 mV in NH4+ cultured mesocosm pots). It improved the root uptake (mainly within IP) of Fe and U (2992.9 to 5010.7 mg•kg-1 Fe and 45.7 to 62.8 mg•kg-1 U in NH4+ cultured root). On the contrary, the NO3- depended strong oxidation ability (23 to 224 mV in NO3- cultured mesocosm pots) inhibited the IP formation and the related aquatic U rhizofiltration efficiency (1568.5 to 2569.5 mg•kg-1 Fe and 26.2 to 49.6 mg•kg-1 U in NO3- cultured root). The aquatic U availability in rhizosphere was also increased via NO3- depended oxidation processes (aquatic U concentration in mesocosm: 1.6 to 589.3 μg•L-1 (NO3-) vs. 1.4 to 58.2 μg•L-1 (NH4+)). The sufficient nitrogen supply is also a significant driving force for high biomass productivity of P. australis. The higher biomass of P. australis increased the U accumulation capacity for root and aboveground tissues. The nitrogen related high biomass accumulation of P. australis also potentially enhanced the share of organic bound U in subhydric soil via plant litters supply.
The IP assisted aquatic U rhizofiltration was also affected by the co-existing metals/metalloids in rhizosphere. The field investigation indicated that high As availability (aquatic As/U ratio: 0.7 to 1.6) inhibited the U retention within IP through the competitive absorption, due to its high affinity to IP. The Ca improved the aquatic U(VI) availability by forming the soluble Ca-uranyl-carbonate compounds. The Ca also potentially competed with hydrated Fe(III) oxides within IP by incorporating with U and encourage the U retention within inner root tissue. The P was beneficial for U retention within IP possibly in form of U-Fe-phosphate complexes. However, it was still need to be proofed in further studies.
Despite of the biogeochemical conditions in rhizosphere, the aboveground transpiration of P. australis also affected the IP formation and related aquatic U rhizofiltration. The higher transpiration rate (TR) of P. australis (3.3±1.2 mm•d-1 in field, 4.5±2.0 mm•d-1 (NH4+)/5.0±2.2 mm•d-1(NO3-) in mesocosm) increased the aquatic nutrient/non-essential elements availability for root uptake. For this reason, the aquatic U rhizofiltration of P. australis (21.8±3.1 mg•kg-1 in field, 62.1±1.0 mg•kg-1 (NH4+)/47.6±1.8 mg•kg-1 (NO3-) in mesocosm) was enhanced under higher TR. The higher TR also promoted the formation of IP and its U retention capacity. Furthermore, the U translocation from root to above ground biomass (mainly in leaves) of P. australis was also enhanced under higher TR. It was potentially benefited by the increased transpirational pull and root uptake of other active mediator (e.g. Ca). The effect of transpiration was also coupled with the different N species on IP assisted aquatic U rhizofiltration. The higher TR depended strong root uptake and assimilation of N increased the biomass accumulation of P. australis. Furthermore, the higher TR also potentially increased the share of root in biomass partition of P. australis. Consequently, the stronger transpiration resulted in the higher aquatic U accumulation in area related root biomass (up to 84.0±3.6 mg•m-2 (NH4+) and 86.4±5.8 mg•m-2 (NO3-) U per season in mesocosm).
In conclusion, it was possible for eutrophic P. australis stands to retain the aquatic U via rhizofiltration. The IP on root surface was a crucial mediator contributing the aquatic U rhizofiltration, especially in iron rich milieu. The efficiency of IP assisted aquatic U rhizofiltration could be further improved under suitable environmental conditions. In this study, these conditions might include: i) reductive rhizosphere environment with active reducers (e.g. NH4+) encouraging Fe(II) generation for IP formation and U retention within it; ii) limited competitive elements (e.g. As and Ca) co-existed with Fe and U in rhizosphere; iii) sufficient nutrients (e.g. N) supply and related high biomass productivity of plant; iv) strong transpiration effect improved the nutrient assimilation of root and also the aquatic U/Fe availability for root uptake. By adjusting these conditions (also include other potential factors not discussed in this study), an effective rhizofiltration technology was supposed to be applied for aquatic U removal.
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Zemlin, Rüdiger [Verfasser]. "Untersuchungen zur genotypischen und phänotypischen Variabilität verschiedener Schilfklone (Phragmites australis) / Rüdiger Zemlin." Berlin : Humboldt-Universität zu Berlin, 2004. http://d-nb.info/1207634816/34.
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Cranney, Chad R. "Control of Large Stands of Phragmites australis in Great Salt Lake, Utah Wetlands." DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/4988.
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Phragmites australis (hereafter Phragmites) often forms dense monocultures, which displace native plant communities and alter ecosystem functions and services. Managers tasked with controlling this plant need science-backed guidance on how to control Phragmites and restore native plant communities. This study took a large-scale approach - to better match the scale of actual restoration efforts - to compare two herbicides (glyphosate vs. imazapyr) and application timings (summer vs. fall). Five treatments were applied to 1.2 ha plots for three consecutive years: 1) summer glyphosate; 2) summer imazapyr; 3) fall glyphosate; 4) fall imazapyr; and 5) untreated control. Dead Phragmites following herbicide treatments was mowed in the first two years. Efficacy of treatments and the response of native plant communities were monitored for three years. We report that fall herbicide applications were superior to summer applications. No difference was found between the two herbicides in their ability to reduce Phragmites cover. Plant communities switched from emergent to open water communities and were limited by Phragmites litter and water depth. Although, some plant communities showed a slow trajectory towards one of the reference sites, cover of important native emergent plants did not increase until year three and remained below 10%. These results suggest that fall is the best time to apply herbicides for effective large-scale control of Phragmites. Active restoration (e.g. seeding) may be needed to gain back important native plant communities. Methods to reduce Phragmites litter after herbicide applications should be considered.
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MICELI, Elisangela. "Bacterial Endophytes: Unexplored Sources Of Biotechnologically Relevant Molecules." Doctoral thesis, Università degli studi di Ferrara, 2019. http://hdl.handle.net/11392/2488023.
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Endophytes are microorganisms which colonize the internal tissues of the plants without causing any harm. Generally, endophytes are described as presenting beneficial functions to the plant host, such as plant growth promoting activity and protection against pathogens. The interaction between endophytes and plants is so close, that the term holobiont has been proposed to define the plant and its microbiome, as if they formed a unique organism. In the last decades, endophytes have gained more attention since there is growing evidence of their capacity to influence the plant’s physiology and to produce bioactive compounds. For example, it has been suggested that endophytes could synthesize compounds similar to the ones produced by the plant host, and modulate the production of plants secondary metabolites. In this context, endophytes appear as a powerful tool. On one hand, the exploration of endophytes allows to deepen our knowledge on the plant-microbiome interaction; on the other hand, the better comprehension of the holobiont can lead to a biotechnological application of endophytes.
Thus, we decided to explore bacterial endophytes from different plants, to better comprehend the structure of their communities, to explore their phenotypic features, prospecting a possible biotechnological application.
In this work, we have analyzed bacterial endophytes from medicinal plants tissues and seeds, and hyperaccumulator plants.
Bacterial communities associated to the medicinal plants Echinacea purpurea and E. angustifolia were already described in our laboratory and showed very specific communities in association to different tissues of the plants (stem/leaves, roots) and rhizosphere. Then, we decided to furtherly explore such communities, mainly focusing on the possible forces that could determine the presence of different communities in different districts of the plants. The performed analysis indicated that bacterial strains themselves could be implied in determining the structure of their own community by means of antimicrobial production, which in turn determine the colonization by adaptive phenotypes.
Endophytes exhibiting intriguing phenotypes, such as the inhibition of human opportunistic pathogens, were furtherly analyzed, by determining their genome sequences. The analysis of such sequences showed that the endophytic strains harbor many gene cluster which might be implied in inhibitory activities, confirming that endophytic bacterial strains are a promising field to investigate.
Endophytic bacterial strains were also analyzed within E. purpurea seeds. In this case, endophytes were observed within the plant’s seeds, extracted, taxonomically and phenotypically characterized.
More recently, we decided to explore endophytes which live in association with Phragmites australis plants, which are largely used in phytodepuration constructed wetlands. This part of the work was possible thanks to the collaboration with G.I.D.A. S.p.A., Gestione Impianti Depurazione Acque. The characterization of such endophytes has shown that they are able to grow in presence of critical elements for wastewater treatment, suggesting their possible application to obtain an enhancement of phytodepuration efficiency.
Overall, the analyses performed in this work increased our knowledge on bacterial endophytes from different sources, their communities structure, and interaction with the host. As a consequence, it represents the starting point to a possible biotechnological application of endophytes, in order to address issues, such as antibiotic resistance and environmental cleanup.Gli endofiti sono microrganismi che colonizzano i tessuti interni delle piante senza causare nessun danno. Generalmente, gli endofiti sono in grado di compiere funzioni come la promozione della crescita della pianta e la protezione contro patogeni. Il termine olobionte indica l’insieme costituito dalla pianta e dal suo microbiota, come se questi costituissero un unico grande organismo. Nelle ultime decadi, gli endofiti sono stati sempre più studiati, poiché è diventata sempre più evidente la loro capacità di influenzare la fisiologia della pianta e la produzione di molecole bioattive. Per esempio, è stato proposto che gli endofiti possono sintetizzare composti simili a quelli sintetizzati dalla pianta ospite e che possono modulare la produzione dei metaboliti secondari della pianta. In questo contesto, gli endofiti appaiono come strumenti di grande potenziale in campo biotecnologico. Per questi motivi, abbiamo deciso di analizzare batteri endofiti da piante diverse, allo scopo di capire meglio la struttura delle loro comunità e di esplorare le loro caratteristiche fenotipiche, prospettando così una possibile applicazione in campo biotecnologico. In questo lavoro, sono state analizzati batteri endofiti da piante medicinali, da semi di piante medicinali e da piante iperaccumulatrici di sostanze tossiche. Recentemente, comunità batteriche associate alle piante medicinali Echinacea purpurea and E. angustifolia sono state analizzate nel nostro laboratorio e hanno mostrato una struttura e composizione molto specifica nei vari tessuti delle piante (foglie/stelo, radici) e nella rizosfera. Successivamente, abbiamo deciso di studiare in modo più approfondito tali comunità, concentrandoci soprattutto nei fattori che potrebbero determinare la presenza di comunità così specifiche in diversi compartimenti delle piante. Le analisi effettuate hanno mostrato che le comunità batteriche stesse potrebbero prendere parte nella strutturazione delle proprie comunità, attraverso la produzione di molecule antimicrobiche, che determinano a loro volta la colonizzazione da parte di ceppi resistenti. Inoltre, alcuni ceppi batterici estratti da Echinacea purpurea e E. angustifolia sono stati ulteriormente analizzati dal punto di vista genetico, attraverso il sequenziamento dei loro genomi. Lo studio delle sequenze ha mostrato che i ceppi endofiti presentano diversi cluster genici presumibilmente coinvolti in attività antibiotica, confermando che tali ceppi potrebbero trovare un’applicazione in campo biotecnologico. Ceppi batterici endofiti sono stati analizzati anche all’interno di semi di E. purpurea. In questo caso, oltre ad osservare la presenza di endofiti all’interno dei semi, endofiti batterici sono stati estratti dai semi e caratterizzati dal punto di vista tassonomico e fenotipico. Recentemente, la nostra analisi degli endofiti si è estesa verso le piante iperaccumulatrici. Sono stati analizzati batteri endofiti in associazione alle piante di Phragmites australis, largamente utilizzate in impianti di fitodepurazione. Questa parte del lavoro è stata possibile grazie alla collaborazione con G.I.D.A. S.p.A, Gestione Impianti Depurazione Acque. La caratterizzazione di tali endofiti ha evidenziato la loro capacità di crescita in presenza di elementi, quali ferro, boro e selenio, che sono critici nel processo di depurazione delle acque. Queste evidenze rendono possibile ipotizzare l’applicazione di tali ceppi per un incremento dell’efficienza depurativa. In conclusione, le analisi effettuate in questo lavoro di tesi hanno permesso di appronfondire le nostre conoscenze riguardo batteri endofiti provenienti da diverse fonti. Questo lavoro rappresenta, inoltre, il punto d’inizio per un possibile utilizzo di tali batteri in campo biotecnologico, al fine di rispondere a precise richieste, quali la resistenza agli antibiotici e la necessità di diminuire l’inquinamento ambientale.
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Edwards, Justin Kenneth. "Reed bed systems for the treatment of wastewaters and for sludge dewatering." Thesis, University of Birmingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343453.
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Taddeo, Sophie. "Spatially explicit tools to assess invasion risks by Phragmites australis in freshwater wetlands." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103660.
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The rapid progression of an exotic haplotype of common reed (Phragmites australis (Cav.) Trin. ex Steud.) in North America is associated with a decline in the plant diversity of wetlands and possibly threatens native haplotypes of Phragmites australis. As prevention is a better strategy than control, a spatially-explicit approach was developed to predict the risk of invasion by the exotic P. australis and its potential impact on a native haplotype. Focusing on a protected wetland of Quebec, Canada where the two haplotypes occur, this study specifically aimed to: 1) compare and contrast the current spatial distribution of the two haplotypes in relation to landscape and land use/land cover variables, and 2) predict, using spatially-explicit models, the potential expansion patterns of the exotic and native P. australis. Results showed that the native P. australis was currently more frequent than the exotic P. australis. At this stage of invasion, native and exotic P. australis still occupied distinct parts of the territory, the native one being associated more with low marsh and areas of lesser human impacts, the exotic one being closer to roads or associated with drier land covers. Perturbations to the natural environment provided invasion foci for the exotic P. australis which is more tolerant to disturbances than the native one. The current distribution of invasion foci of exotic P. australis and its association to a broad range of conditions resulted in predicted expansion patterns where the cover of the exotic P. australis could potentially surpass the cover of the native P. australis within 10 years. This could lower the conservation value of the protected wetland and increase the competition with native colonies of P. australis where the two haplotypes intersect.La progression d'un haplotype exotique du roseau commun (Phragmites australis (Cav.) Trin ex Steud.) en Amérique du nord réduit la diversité végétale des milieux humides en plus de menacer les haplotypes indigènes de Phragmites australis. La prévention étant plus efficace que le contrôle, une approche spatialement explicite visant à prédire les risques d'invasion par l'haplotype exotique et son impact sur un haplotype indigène a été développée. Cette étude conduite dans un marais protégé du Québec (Canada) visait à : 1) comparer et expliquer la distribution spatiale actuelle de ces deux haplotypes sur la base de leur relation à des variables de couverture/utilisation du sol et du paysage et 2) prédire à partir de modèles spatialement explicites les patrons d'expansion futures des haplotypes exotique et indigène de P. australis. À ce stade-ci de l'invasion, les haplotypes occupent des zones distinctes du territoire ; le P. australis indigène est associé aux bas marais et à des zones où l'influence anthropique est faible, tandis que le P. australis exotique se trouve près des routes et dans les milieux plus secs. Les perturbations au milieu naturel constituent des foyers d'invasion propices à l'haplotype exotique qui semble tolérer un éventail de conditions environnementales plus large que l'haplotype indigène. La modélisation des patrons d'expansion de l'haplotype a démontré que celui-ci pourrait surpasser en couverture l'haplotype indigène d'ici 10 ans, en raison de son association à un vaste éventail de conditions environnementales. Cette progression de l'haplotype exotique pourrait réduire la valeur de conservation du milieu humide et intensifier la compétition avec les colonies indigènes de P. australis.
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Maheu-Giroux, Mathieu 1981. "The landscape ecology of the invasive species Phragmites australis in anthropogenic linear wetlands /." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=111930.
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The recent and rapid expansion of Phragmites australis in North America provides an opportunity to relate dispersal patterns to landscape structure. Linear wetlands, such as roadside or agricultural ditches, may serve as corridors that facilitate dispersal at the landscape scale, but there is little quantitative information on patterns of invasion in these habitats. Remote sensing data, GIS, and field observations were used (1) to assess the feasibility of mapping populations of P. australis in linear wetlands and (2) to quantify and explain recent invasion patterns of P. australis in two periurban areas of southern Quebec. An accuracy assessment demonstrated the reliability of aerial photographs to map populations in linear habitats. The intrinsic growth rate observed is high compared to those reported in natural wetlands. Spatial analysis revealed that colonization events are not constrained by the network's configuration. Logistic regressions confirmed the effect of road corridors on the spread of P. australis.
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Abeysinghe, Tharindu Hasantha. "Mapping Invasive Phragmites australis in the Old Woman Creek Estuary Using Remote Sensing." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1546430964233226.
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Poznik, Jenica. "Comparison of swamp forest and Phragmites Australis communities at Mentor Marsh, Mentor, Ohio." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1407489569.
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Tarr, Jason Alec. "An evaluation of the Phragmites australis reed use by communities neighbouring the Tembe Elephant Park, Maputaland, KwaZulu-Natal, South Africa." Diss., Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-03302007-162647.
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Correia, Carolina Mourão. "Fitorremediação de águas contaminadas com fármacos." Master's thesis, Universidade de Évora, 2010. http://hdl.handle.net/10174/16262.
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A presença de compostos farmacêuticos e seus metabolitos no ambiente aquático tornou-se nos últimos anos num problema ambiental emergente. Em particular, uma especial atenção tem vindo a ser dada aos antibióticos dada a sua ecotoxicidade e devido ao problema específico de desenvolvimento de estirpes bacterianas resistentes à sua acção. A baixa eficiência das ETARs na remoção da maior parte deste tipo de poluentes é uma das principais razões para a contaminação dos recursos hídricos e, portanto, é necessário o desenvolvimento de novos processos de tratamento que sejam eficientes na remoção de fármacos, mas se mantenham a níveis de custo aceitáveis. A utilização de leitos construídos de macrófitas (LCMs) tem surgido nas últimas décadas como um sistema de tratamento de efluentes líquidos de baixo custo e com elevadas eficiências na remoção de diversos poluentes orgânicos xenobióticos, incluindo alguns fármacos. Este trabalho teve como objectivo principal avaliar a eficiência de remoção de um antibiótico, a oxitetraciclina, por um microcosmos de LCM utilizando LECA 2/4 como matriz de suporte e plantado com Phragmites australis. Preliminarmente foi avaliada a capacidade de adsorção da oxitetraciclina pelo material LECA, a diversas concentrações iniciais, em água e num efluente recolhido após um tratamento secundário. A LECA mostrou elevada capacidade de remoção da oxitetraciclina, quer em água quer em efluente, embora neste último meio se tenha verificado uma ligeira diminuição na eficiência de remoção (4 a 8 %). A quantidade de oxitetraciclina adsorvida relacionou-se de uma forma linear com a quantidade inicial, tendo a LECA demonstrado estar ainda distante da saturação da sua capacidade de adsorção aos níveis de concentração testados (1.5 a 36 mg L-1). Posteriormente foi avaliada a eficiência de remoção de oxitetraciclina alcançada pelo microcosmos de LCM, a qual se verificou ter sido muito elevada (> 99 %) podendo a maior parte da eficiência ser atribuída à matriz de suporte através de fenómenos de adsorção. No entanto, comparando as remoções alcançadas em leitos plantados e não-plantados verificou-se que as plantas permitiram acelerar significativamente o processo de remoção. A cinética de remoção caracterizou-se por um passo inicial rápido, em que nas primeiras 6 h foi removida cerca de 88 % da quantidade inicial de oxitetraciclina nos leitos plantados e 67 % nos leitos não plantados, e por um passo subsequente mais lento, com a quase total remoção do fármaco, tendo as concentrações de equilíbrio sido alcançadas ao fim de 120 h nos leitos plantados e 144 h nos leitos não plantados. O facto de não se ter detectado oxitetraciclina em tecidos de folhas das plantas usadas nos ensaios sugere que o fármaco não é absorvido pelas plantas, ou, sendo absorvido, não é translocado para a parte aérea ou, então, sofre uma rápida metabolização/transformação (num período inferior a 48 h). Mesmo considerando a hipótese de não ser absorvido pelas plantas, é claro, pelos resultados, que estas têm um efeito positivo na sua remoção, podendo a influência das plantas dever-se a um estímulo do desenvolvimento dos microrganismos que se verificou serem capazes de biodegradar a oxitetraciclina e/ou à libertação de exsudados pelas raízes que poderão catalisar enzimaticamente a degradação deste antibiótico. Os resultados deste estudo apontam para a potencial utilização dos LCMs, tendo LECA como matriz de suporte e plantados com Phragmites australis, para a remoção de oxitetraciclina de efluentes contaminados com este antibiótico; ABSTRACT: The occurrence of pharmaceutical compounds and their metabolites in the aquatic environment has become an emergent environmental problem over the last years. A special attention is being given to antibiotics in particular, considering its ecotoxicity and the specific problem of the development of antibiotic resistant strains of bacteria. One of the main reasons for the contamination of water resources with pharmaceuticals is the low efficiency of wastewater treatment plants in removing most of these pollutants. Therefore, the development of efficient and cost-effective wastewater treatment processes is necessary to deal with this type of pollutants. The constructed wetlands systems (CWS) have become, over the last decades, a low cost and low maintenance wastewater treatment alternative which has already shown high efficiencies in the removal of several organic xenobiotic compounds, including some pharmaceuticals. The main objective of this work was to evaluate the removal efficiency of an antibiotic, oxytetracycline, by a microcosm of a CWS using LECA 2/4 as the support matrix and planted with Phragmites australis. In preliminary studies, the adsorption capacity of oxytetracycline by LECA was evaluated for several initial concentrations of oxytetracycline, in water and in a wastewater that was collected after secondary treatment. LECA has shown a high capacity for the removal of oxytetracycline, both in water and in wastewater, although some slight decrease in the removal efficiency (4 to 8 %) has been observed in latter. The adsorbed amounts of oxytetracycline presented a linear relationship with the initial amounts which showed that the adsorption capacity of LECA was still far from saturation at the concentration levels tested (1 – 36 mg L-1). Following, assays were conducted in order to evaluate the oxytetracycline removal efficiency by the CWS microcosms. Results have shown high removal efficiencies (> 99 %) which could be attributed mostly due to adsorption processes occurring at the support matrix. Nevertheless, by comparing the removals attained in planted beds with those obtained by unplanted beds, it could be observed that the presence of plants led to a significant acceleration of the removal process. The removal kinetics was characterized by a fast initial step that was responsible, during the first 6 h, for the removal of about 88 % of the initial amounts of oxytetracycline in the planted beds and 67 % in the unplanted beds. A subsequent slower step allowed for the additional removal of almost all remaining pharmaceutical, and the equilibrium concentrations were attained after 120 h and 144 h in the planted and unplanted beds respectively. The fact that no detectable amounts of oxytetracycline were found in leaf tissues of the plants used in the assays suggests that either the pharmaceutical is not taken up by the plants or, if it is, it is not translocated to aerial parts or it is quickly metabolized/transformed (within a period shorter than 48 h). Even considering the hypothesis that oxytetracycline is not taken up by the plants, it is quite clear that, considering the results obtained, plants have a positive effect in its removal. This contribution may consist of a stimulus for the development of microorganisms that were shown to be able to biodegrade oxytetracycline and/or the release of exudates that may enzymatically catalyze the degradation of this antibiotic. The results of this study point out the potential for the use of CWS, with LECA as support matrix and planted with Phragmites australis, for the removal of oxytetracycline from contaminated wastewaters.
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Parks, LuElla Marie. "A comparison of Nebo Hill and Sedalia points." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/6254.
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Thesis (M.A.) University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 28, 2007) Includes bibliographical references.
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Ma, Ying. "Monitoring of heavy metals in the Bottelary River using Typha capensis and Phragmites australis." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
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The aim of this study was to use plants to determine the degree of heavy metal contamination in water and sediments in order to effectively monitor and provide possible recommendation to improve the water quality in the aquatic ecosystem of the Bottelary River.
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Boar, R. R. "Aspects of the ecology of the common reed, Phragmites australis in the Norfolk Broadland." Thesis, University of East Anglia, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380975.
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ABRANTES, Lorena Lemes Martins. "Tratamento de esgoto sanitário em sistemas alagados construídos utilizando Typha angustifolia e Phragmites australis." Universidade Federal de Goiás, 2009. http://repositorio.bc.ufg.br/tede/handle/tde/624.
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Previous issue date: 2009-08-28This study aimed to assess the efficiency of two vegetal species in the treatment of the sanitary sewer, in constructed wetlands system. Specifically, it aimed to evaluate the efficiency of the species Typha angustifolia (narrow-leaf cattail) and Phragmites australis (common reed), in their possible combinations, in the treatment of the sanitary sewer, in a constructed wetlands system, of vertical subsuperficial flux, with two flux directions (ascendant and descendant), related to the attributes: organic material, apparent color, ammonium nitrogen, phosphate, turbidity, chlorides, hardness, electrical conductivity, solids and thermotolerant coliforms. The experiment was conducted in the Researching Station in Sewer Treatment with Plants RSSTP (UFG), located in the Sewer Treatment Station (STS) Samambaia, in Goiânia, Goiás State, Brazil. The experimental unit has twenty four modules, grouped sequences of two modules (initial and final modules). Raw sewage which comes from the initial part of the ETE facultative pond was pumped into the deep of the treatment initial modules, filled up with substrate layers (in the deep filled up with rocks category number 3, followed by rocks category number 1, washed sand, and again rocks category number 1) and planted with cattail or reed. After going up by the vegetated substrate (ascendant vertical flux) the sewer was drained and conducted to the final treatment modules equally filled up and vegetated with one of the species, although being applied in the surface and drained by the deep (vertical descendant flux). The tax of sewer application was of 80 L.m-2dia-1, corresponding to a treatment area of 2 m2 per inhabitant. A year after the system implementation, during the period of 6 months, sewer samples were collected after passing through the flux sequences, each one with the combination of the two vegetal species, for the evaluation of the sewer attributes and calculation of the efficiency in the treatment. The results were analyzed by the Statistical Analysis System (SAS program), being used the tests F and the Tukey Kramer, considering 5% of probability. There were no meaningful differences in the efficiency of the treatments in the removal of the attributes: biochemical oxygen demand, chemical oxygen demand, ammonium nitrogen, phosphate, thermotolerant coliforms, chlorides, hardness, dissolved total solids and volatile total solids. The cattail was more efficient in the apparent color removal and turbidity. The reed presented more efficiency in the total solids removal. The position of the plant in the module sequence did not influence the apparent color and turbidity removals. The reed in the final module increased the removal of the attributes total solids and fixed total solids. It´s possible to verify that the technology of sewer treatment by using plants is efficient, since the species cattail and reed in the adopted system, provided results with removals higher 60% for the of the attributes: biochemical oxygen demand, chemical oxygen demand, apparent color, ammonium nitrogen, phosphate, thermotolerant coliforms and turbidity.
O presente estudo teve como objetivo avaliar a eficiência de duas espécies vegetais no tratamento do esgoto sanitário, em um sistema de alagados construídos. Especificamente, objetivou-se avaliar a eficiência das espécies Typha angustifolia (Taboa) e Phragmites australis (Caniço), em suas combinações possíveis, no tratamento de esgoto sanitário, em um sistema de alagados construídos, de fluxo subsuperficial vertical, com dois sentidos de fluxo (ascendente e descendente), concernente aos atributos: matéria orgânica, cor aparente, nitrogênio amoniacal, fosfato, turbidez, cloretos, dureza, condutividade elétrica, sólidos e coliformes termotolerantes. O experimento foi conduzido na Estação de Pesquisas em Tratamento de Esgotos com Plantas Eptep (UFG), localizada na Estação de Tratamento de Esgotos (ETE) Samambaia, em Goiânia, GO. A unidade experimental possui vinte quatro módulos, agrupados em sequências de dois módulos (módulos iniciais e finais). Esgoto sanitário bruto proveniente da parte inicial da lagoa facultativa da ETE foi bombeado no fundo de módulos iniciais de tratamento preenchidos com camadas sobrepostas de substrato (no fundo com brita número 3, na sequência brita número 1, areia lavada e novamente brita número 1) e plantados com taboa ou caniço. Após subir pelo substrato vegetado (fluxo vertical ascendente) o esgoto era drenado e conduzido aos módulos finais de tratamento, igualmente preenchidos e vegetados com uma das espécies, todavia sendo aplicado na superfície e drenado pelo fundo (fluxo vertical descendente). A taxa de aplicação de esgoto foi de 80 L.m-2dia-1, correspondendo a uma área de estação de tratamento de 2 m2 por habitante. Um ano após a implantação do sistema, por um período de seis meses, amostras do esgoto foram coletadas após passar pelas sequências de fluxo, cada uma com uma combinação das duas espécies vegetais, para avaliação dos teores de atributos do esgoto e cálculo da eficiência do tratamento. Os resultados foram analisados pelo programa Statistical Analysis System (SAS), realizando-se os testes F e de Tukey Kramer, a 5% de probabilidade. Não houve diferença significativa entre as eficiências dos tratamentos na remoção dos atributos: demanda bioquímica de oxigênio, demanda química de oxigênio, nitrogênio amoniacal, fosfatos, coliformes termotolerantes, cloretos, dureza, sólidos totais dissolvidos e sólidos totais voláteis. A taboa foi mais eficiente na remoção da cor aparente e da turbidez. Já o caniço apresentou uma eficiência maior na remoção de sólidos totais. A posição da planta na sequência de módulos não influenciou na remoção da cor aparente e da turbidez. O caniço no módulo final influenciou positivamente na remoção dos atributos sólidos totais e sólidos totais fixos. Verifica-se que a tecnologia de tratamento de esgoto por plantas é eficiente, uma vez que as espécies taboa e caniço no sistema de fluxo subsuperficial vertical ora adotado proporcionaram resultados com remoções superiores a 60% para os atributos demanda bioquímica de oxigênio, demanda química de oxigênio, cor aparente, nitrogênio amoniacal, fosfatos, coliformes termotolerantes e turbidez.
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Chu, Wing Kei. "Accumulation and transformation of DDT and PCBs by Phragmites australis and Oryza sativa L." HKBU Institutional Repository, 2004. http://repository.hkbu.edu.hk/etd_ra/530.
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Campana, Michael Leadbeater. "The Effect of Phragmites australis Invasion on Community Processes in a Tidal Freshwater Marsh." W&M ScholarWorks, 1998. https://scholarworks.wm.edu/etd/1539617970.
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Lelong, Benjamin. "La dissémination du roseau commun (Phragmites australis) dans le paysage québécois : une analyse spatio-temporelle." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25735/25735.pdf.
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Guo, Lin. "Bioremediation of Acid Mine Drainage Contaminated Soil by Phragmites australis and Rhizosphere Bacteria." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1403637340.
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White, Sean D. "Internal pressurisation and convective flow in two species of emergent macrophyte; Typha domingensis and Phragmites australis /." Title page, contents and summary only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09phw5877.pdf.
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Fennell, Jeremy Daniel. "Phragmites Australis Patch Characteristics in Relation to Watershed Landcover Patterns on the Eastern Shore of Virginia." VCU Scholars Compass, 2007. http://scholarscompass.vcu.edu/etd_retro/21.
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Phragmites australis is a perennial grass presently invading many intertidal and freshwater wetlands throughout much of the Atlantic Coast of North America. The spread of Phragmites into coastal wetlands is in part determined by available freshwater and nutrients, especially nitrogen, within the watershed where Phragmites populations occur. The Eastern Shore of Virginia is an intensive agricultural area, and watershed landcover may play a major role in Phragmites invasion. Forty-five Phragmites patches were sampled in eight VA Eastern Shore mainland watersheds and on a barrier island. Regardless of watershed landcover characteristics, there was little variation in Phragmites australis patch characteristics along the oceanside of the entire Eastern Shore of Virginia. Phragmites is a generalist with broad environmental tolerances. Thus, successful management and eradication plans may have broad scale application for this invasive grass.
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Gilson, Eoin. "Biogas production potential and cost-benefit analysis of harvesting wetland plants (Phragmites australis and Glyceria maxima)." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-34424.
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Biogas production from energy crops grown on arable land often competes with food and feed production. Wetland plants offer an alternative source of biomass as well as offering a number of environmental benefits such as nutrient removal from wastewaters, carbon sequestration and reducing the use of mineral fertilizer. The aim of this study is to investigate the effect of harvest time on biogas production of Phragmites australis and Glyceria maxima and to perform a cost-benefit analysis of using these wetland plants as a substrate for biogas production. The results of the batch experiment show that the overall biogas production and specific methane yields of biomass harvested in June was higher than biomass harvested in September due the increased lignocellulosic nature of the more mature September plant. The cost-benefit showed that in Sweden it is not currently profitable to solely use wetland plants for biogas production. For both species the highest costs were seen in the June harvested biomass, this was due to the much higher fresh weight and increased transportation costs. For both species the highest revenues generated were the June harvested biomass, this was due to the higher specific methane yields. It was found that the harvest time that was closest to profitability from both species was the June harvest for Phragmites australis. Although the costs were higher for harvesting in June, this was outweighed by the higher amount of electricity produced for this scenario. If transportation distance was to be increased it could result in September being the favourable harvest time. Therefore, individual circumstances of the farmers could decide which is the optimal harvest time. Although solely using wetland plants for biogas production is not currently profitable, co-digestion and pre-treatment are options to investigate that could change this. Also if a greater financial value is put on the socioeconomic benefits such as increased biodiversity, aesthetic value and global warming mitigation it may be financially viable in the future.
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Krumscheid-Plunkert, Priska. "Experimentelle Untersuchungen zur Nährstoffabhängigkeit des Schilfrohrs (Phragmites australis (Cav.) Trin. ex Steud.) : Implikationen für Röhricht-Sanierungsstrategien /." Konstanz : Hartung-Gorre, 1992. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=002946370&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Long, Arin Lexine. "Distribution and Drivers of a Widespread, Invasive Wetland Grass, Phragmites australis, in Great Salt Lake Wetlands." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/3869.
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Non-native invasive plant species can often have negative effects on native ecosystems, such as altered nutrient cycling, decreased habitat for wildlife, and outcompeting native plants. Around the Great Salt Lake (GSL), Utah, the invasive wetland grass Phragmites australis has become abundant in wetlands around the lake. Phragmites is replacing many native wetland plants provide important waterfowl habitat around the GSL. For successful management of Phragmites in GSL wetlands, it is important to know the current distribution of Phragmites, as well as areas that might be vulnerable to future invasion by Phragmites. To do this, we used multispectral aerial imagery to map the current distribution of Phragmites. We then created a model that statistically related the Phragmites distribution data to a suite of environmental predictor variables such as salinity, proximity to nutrient sources, or proximity to roads. Results from our model suggest that Phragmites is more likely to be found in wetland areas close to point sources of pollution, with lower elevations with prolonged inundation, and with moderate salinities. We used these results to identify areas around GSL that might be vulnerable to future invasion. Results from our study will assist wetlands managers in prioritizing areas for Phragmites monitoring and control by closely monitoring areas of prime Phragmites habitat.
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PIETRANGELO, Laura. "Analysis and characterization of microbial biofilm associated with the roots of Phragmites australis and Typha latifolia." Doctoral thesis, Università degli studi del Molise, 2018. http://hdl.handle.net/11695/84159.
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Phragmites australis e Typha latifolia sono due macrofite comunemente presenti nelle zone umide naturali e artificiali. Le radici di queste piante stabiliscono interazioni con una vasta gamma di microrganismi, denominati collettivamente “microbiota”. Queste interazioni contribuiscono al processo naturale di fitodepurazione, per cui le sostanze inquinanti sono rimosse dai corpi idrici contaminati attraverso le piante. Lo strato più esterno del corpus radicale, il rizoplano, dove i microrganismi formano aggregati specializzati designati come biofilm, è un punto caldo per queste interazioni. Studi precedenti suggeriscono che i membri del microbiota biofilm-formanti svolgono un ruolo cruciale nel processo di fitodepurazione. Tuttavia, la composizione e le dinamiche di reclutamento del microbiota di Phragmites e Typha restano poco chiare. Abbiamo quindi deciso di indagare la composizione e le capacità funzionali del microbiota batterico che colonizza l'interfaccia radice-suolo di P. australis e T. latifolia. Utilizzando l'approccio di sequenziamento Illumina MiSeq del gene 16S del rRNA abbiamo dimostrato che, malgrado una composizione differente dell'inoculo iniziale del bacino, il microbiota associato alla rizosfera e al rizoplano di P. australis e di T. latifolia tende a convergere verso una comune composizione tassonomica dominata dai membri dei phyla Acidobacteria, Actinobacteria, Firmicutes, Proteobacteria e Planctomycetes. Queste differenze sono state rispecchiate dalla diversificazione strutturale del microbiota ai livelli tassonomici più bassi. Ciò indica l'esistenza di un processo di selezione che agisce all'interfaccia radice-suolo di queste piante acquatiche e ricorda quello osservato per le piante terrestri. La grandezza di questo processo di selezione è massima al livello del rizoplano, dove abbiamo identificato diversi taxa batterici arricchiti e discriminati fra i comparti rizoplano e rizosfera attraverso meccanismi specie-dipendenti ed –indipendenti. Questo ci ha portato a ipotizzare che la diversificazione strutturale della comunità del rizoplano sia collegata a specifiche capacità metaboliche del microbiota. Abbiamo testato questa ipotesi integrando l'analisi di sequenziamento con un approccio a due fronti. In primo luogo, abbiamo dedotto il potenziale funzionale di queste comunità attraverso un approccio predittivo metagenomico utilizzando il software PICRUSt e abbiamo scoperto che i trasportatori e i geni codificanti per i fattori di trascrizione sono una caratteristica distintiva delle comunità arricchite nel rizoplano. Parallelamente, abbiamo usato la Microscopia Elettronica a Scansione, l'isolamento batterico e l’analisi biochimica per dimostrare che i batteri arricchiti nel rizoplano hanno una predilezione per i membri formatori di biofilm. Nell’insieme i nostri dati apriranno il campo verso lo sfruttamento razionale delle interazioni pianta-microbiota ai fini della fitodepurazione.Phragmites australis and Typha latifolia are two macrophytes commonly present in natural and artificial wetlands. Roots of these plants engage in interactions with a broad range of microorganisms, collectively referred to as the microbiota. These interactions contribute to the natural process of phytodepuration, whereby pollutants are removed from contaminated water bodies through plants. The outermost layer of the root corpus, the rhizoplane, is a hot-spot for these interactions where microorganisms establish specialized aggregates designated biofilm. Earlier studies suggest that biofilm-forming members of the microbiota play a crucial role in the process of phytodepuration. However, the composition and recruitment cues of the Phragmites and Typha microbiota remain poorly understood. We therefore decided to investigate the composition and functional capacities of the bacterial microbiota thriving at the P. australis and T. latifolia root-soil interface. By using 16S rRNA gene Illumina MiSeq sequencing approach we demonstrated that, despite a different composition of the initial basin inoculum, the microbiota associated with the rhizosphere and rhizoplane of P. australis and T. latifolia tend to converge towards a common taxonomic composition dominated by members of the phyla Acidobacteria, Actinobacteria, Firmicutes, Proteobacteria and Planctomycetes. These differences were mirrored by a structural diversification of the microbiota at lower taxonomic ranks. This indicates the existence of a selecting process acting at the root-soil interface of these aquatic plants reminiscent of the one observed for land plants. The magnitude of this selection process is maximum at the level of the rhizoplane, where we identified different bacterial taxa enriched in and discriminating between rhizoplane and rhizosphere fractions in a species-dependent and –independent ways. This led us to hypothesize that the structural diversification of the rhizoplane community underpins specific metabolic capabilities of the microbiota. We tested this hypothesis by complementing the sequencing survey with a two-pronged approach. First, we inferred the functional potential of these communities through a predictive metagenomics approach using the software PICRUSt and we found that transporters and transcription factors-encoding genes are a distinctive feature of the rhizoplane-enriched communities. In parallel, we used Scanning Electronic Microscopy, bacterial isolation and a biochemical assay to demonstrate that rhizoplane-enriched bacteria have a bias for biofilm-forming members. Together, our data will set the stage towards the rational exploitation of plant-microbiota interactions for phytodepuration.
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Back, Christina L. "Effects of Common Reed (Phragmites australis) Invasion and Glyphosate and Imazapyr Herbicide Application on Gastropod and Epiphyton Communities in Sheldon Marsh Nature Reserve." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275331237.
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Kennedy, Emmalisa. "Effects of control of the invasive plant, Phragmites australis, on microbes and invertebrates in detritus." [Kent, Ohio] : Kent State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1216395163.
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Thesis (M.S.)--Kent State University, 2008.Title from PDF t.p. (viewed Oct. 27, 2009). Advisor: Laura Leff. Keywords: Phragmites australis; Scirpus cyperinus; glyphosate; microbes; ergosterol; invertebrates. Includes bibliographical references (p. 47-59).
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Packett, Carmen Rebekah. "Effects of Salinity and Nitrogen on the Distribution and Growth of Phragmites australis along the Rappahannock River." W&M ScholarWorks, 2005. https://scholarworks.wm.edu/etd/1539626837.
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Wahl, Edman Daniel. "Fytoremediering med Salix sp och bladvass (P. australis) : - Reduktion av tungmetaller och användning som biobränsle." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210923.
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Förorenad mark är ett stort och ofta påkostat problem i Sverige och världen. Ofta används konventionella metoder som schaktningsarbete för att åtgärda områdena, men orsakar även höga kostnader och en signifikant inverkan på miljön. I och med dessa problem har fytoremediering, dvs. växters förmåga att åtgärda förorenad mark, som åtgärdsmetod blivit allt mer populär de senaste åren. I denna studie undersöktes bladvass (Phragmites australis) och Salix sp för potentiell upptagningsförmåga av tungmetaller genom att analysera tungmetallminskningen i jorden. Växterna undersöktes i syfte att användas inom fytoremediering, samt som potentiell biobränslekälla. I projektet utfördes en fältstudie vid Ekeby avloppsreningsverk i Eskilstuna. Tre provpunkter på området valdes ut baserat på tidigare miljötekniska undersökningar av Norconsult AB. Jordmaterial förorenat med tungmetaller och lokala populationer av Salix sp och bladvass samlades in för analys i ett krukexperiment i vilket skillnader i metallhalter i jorden före och efter odling undersöktes. Totalt odlades 3 Salix sp-och 3 bladvass-skott i jordmaterial från varje provpunkt i växthus vid Stockholms Universitet. Jordmaterial från varje provpunkt användes som kontrollprov och fick stå i samma växthus under krukexperimentet. De insamlade växterna odlades i den förorenade jorden under 80 dagar och vattnades regelbundet med destillerat vatten. Efter tillväxtperioden visade resultatet inte på några signifikanta skillnader mot kontrolljorden. Orsaken antas bero på den relativt korta odlingsperioden, det låga antalet växtindivider som användes och antalet analyser som genomfördes. Åtgärdspotentialen för de lokala Salix sp- och bladvassväxterna skulle sannolikt kunna bestämmas på ett bättre sätt genom analyser avseende metallhalt i skördad växtbiomassa. Salix och bladvass används som biobränsle i Sverige, men kvalité, hantering och värmeverkens praktiska begränsningar påverkar avkastningen och det avfall som måste tas om hand. För att utvärdera ekonomiska och miljömässiga vinster genom implementering av fytoremediering på förorenad mark bör vidare studier genomföras för att utvärdera när under säsongen växterna bör skördas för största upptag av föroreningar med hänsyn till växterna som konkurrenskraftigt biomaterial. Fytoremediering har påvisats fungera genom flera studier, men en tydlig organisation och kunskap om vilka miljötekniska egenskaper som gäller för det lokala området är väsentlig för att implementera denna åtgärdsmetod med gott resultat.Contaminated land is a big issue in Sweden and worldwide. Conventional methods like excavation are commonly used to remediate polluted areas, but also cause elevated costs and a significant environmental impact. The interest in phytormemediation, which is the ability of plants to remediate contaminated land, as it has become more popular during recent years. Common reed (Phragmites australis) and Salix sp. were tested in this study to assess the potential for heavy metal uptake by analysis of heavy metal reduction in the soil. The plants were assessed with the purpose to be used within phytoremediation as well as potential source for biofuel. A field study was included in this project at Ekeby wastewater treatment plant in Eskilstuna, Sweden. Three sample points were chosen based on previous environmental studies conducted by Norconsult AB. Soil material contaminated with metals and local populations of Salix sp and common reed were collected for analysis in a pot experiment were differences in metal content in the soil before and after cultivation were investigated. In total 3 shoots of Salix sp and 3 shoots of common reed were cultivated in soil material from each sample point in a greenhouse at Stockholm University. Soil material from each sample point were used as control and were placed in the same greenhouse during the pot experiment. The sampled plants were grown in contaminated soil material for 80 days and regularly irrigated with distilled water. The soil material was analyzed with respect to metals before and after cultivation of the local plants. After the growth period the results did not show any significant differences in the metal content of the soil compared to the control pot. It is assumed that the cause is due to the relatively short cultivation period, the low number of individual plants used and the number of analyzes performed. The remediation potential for the local plants of Salix sp and common reed could probably be determined in a more suitable way though analysis of metals from the harvested plant material. Salix and common reed are used as biofuel in Sweden, but quality, management and practical limitations affect the yield and the waste that has to be taken care of. Further studies should be carried out to evaluate economic and environmental benefits through implementation of phytoremediation on contaminated land to assess when during the season the plants should be harvested to accumulate the greatest level of contaminants with consideration to the plants as a competitive bio-material. Phytoremediation works and has been demonstrated through several studies. However, a clear organization and knowledge of the local environmental characteristics of the contaminated site are vital features to implement this measure with a good result.