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The use of macrophytes has been proposed recently as a suitable option for the phytostabilization or rhizofiltration of soils or waters contaminated by trace elements. As one of the most representative species of this type of plant, common reed (Phragmites australis (Cav.) Trin. ex Steud.) has shown tolerance to high concentrations of potentially hazardous elements, as is the case of arsenic. However, a deeper knowledge of how these plants deal with this toxicity, including their oxidative response, is needed for the optimum utilization of this species in phytoremediation procedures. In fact, little is known about how common reed plants react to As toxicity or the tolerance limits and accumulation potential of this species. In this work, common reed plants were exposed to a range of As(V) mass concentrations (0.5–10 mg L) in a hydroponic experiment, and the performance of the plants (growth, photosynthetic pigments, and oxidative stress related parameters) was evaluated and related to the major As species present in the different parts of the plants. The plants did not show any apparent symptom of toxicity and no significant effects were found for any of the different plant parameters analyzed. Arsenic was mostly accumulated as As(III) in the roots of the plants, and almost no translocation to the aerial part of the plants was observed for any of the As species analyzed. Common reed has shown a high capacity for As accumulation in its roots with no signs of toxicity, despite small nutrient imbalances. Thus, it can be considered to be a good candidate for use in the rhizofiltration and phytostabilization of As contaminated waters and soils, respectively.

Drastic changes in the water regime of trace elements (TEs) contaminated soils under semiarid conditions, from completely dry to flooding situations, may alter the solubility of the contaminants and, therefore, their potential mobility and availability to plants. Certain macrophyte species have shown a promising suitability for their use in the phytoremediation of TEs contaminated soils under fluctuating flooded–unflooded conditions, as a consequence of their high resistance and tolerance to contamination. Similarly, different water conditions occur during rice (Oryza sativa) cultivation, a species often used as a model plant for TEs toxicity studies. The aim of this work was to study the tolerance and oxidative response to TEs of common reed (Phragmites australis) and rice grown in contaminated mining soils, when exposed to different water saturation conditions. Both species (common reed and rice) were cultivated in three different contaminated soils from the Sierra Minera of La Unión-Cartagena (SE-Spain) under contrasting water saturation conditions (flooded and unflooded) in a pot experiment. Soil EC and elevated metal (mainly Cd and Zn) soluble concentrations conditioned the survival of the plants. Whereas, As accumulation in the aerial part of both species influenced the most oxidative stress homeostasis. Common reed showed to be a good candidate for its use in the phytostabilization of TEs contaminated soils under both flooded and unflooded conditions.

The climate on earth keeps getting warmer where heat waves, eutrophication, rising sea levels, extreme weather like flooding, droughts and wildfires are an expanding problem. The focus of this bachelor thesis is to determine the potential of mitigating eutrophication and while contributing to blue growth by harvesting and make use of reeds like Phragmites australis and Arundo donax. Reeds have the ability to quickly absorb nutrients from aquatic environments and there are opportunities to use them as a feedstock for producing biochar to be potentially used in areas such as soil improvement, fodder additive and carbon sequestration. Additionally, optimal biochar properties for the observed applications gets analysed. The thesis is based on a systematic literature review and an interview with Niclas Anvret at the non-profit organisation “Race for the Baltic”. Results show that biochar produced according to parameters such as heating rate, biomass species and especially, different temperatures, results in varied characteristics that change the biochar's adsorption abilities, nutrient retention, alkalinity, stability, surface area and porosity volume. The different applications of biochar are, however, not easily determined. This is because of the fact that certain biochar properties, that are prominent in entirely different pyrolysis conditions, could both be beneficial for the same application. Additionally, the different attributes sometimes influence each other which gives rise to unclear patterns affecting use potential. To overcome these issues, more research is needed to clarify the correlations between attributes of the biochar and to determine which characteristics of biochar are best suited for each application. In terms of how large-scale harvesting of reed could affect the ecosystem is also unclear, there is not enough research regarding the question to be able to draw clear conclusions. The reasoning behind this is that there are knowledge gaps, geographi, Klimatet på jorden blir allt varmare och värmeböljor, övergödning, stigande havsnivåer, extrema väder som översvämningar, torka och bränder är ett stigande problem. Syftet med denna kandidatuppsats är att undersöka potentialen att mildra eutrofiering och samtidigt bidra till blå tillväxt genom att skörda - och använda sig av vass som Phragmites australis och Arundo donax. Vass har en framträdande förmåga att absorbera näringsämnen. Det finns därför möjligheter att använda dem som råvara för att producera biokol som potentiellt kan användas i områden såsom jordförbättring, fodertillsatser och kolbindning. Utöver detta undersöks optimala egenskaper för biokol enligt de observerade applikationerna. Kandidatuppsatsen bygger på en systematisk litteraturstudie och en intervju med Niclas Anvret på den ideella organisationen ”Race for the Baltic”. Resultaten indikerar att biokol, producerad i pyrolys enligt parametrar som uppvärmningshastighet, biomassa och i synnerhet olika temperaturer, resulterar i varierande egenskaper som förändrar biokolets absorptionsförmåga, bibehållande av näring, alkalinitet, stabilitet, ytarea och porositetsvolym. De olika tillämpningarna av biokol är emellertid svåra att avgöra på grund av vissa biokolegenskaper. Dessa egenskaper är framträdande under helt olika pyrolysförhållanden men kan samtidigt vara fördelaktiga för samma typ av applikation. Dessutom påverkar de olika attributen ibland varandra vilket ger upphov till komplexa trender som påverkar användningspotentialen. För att kunna dra tydliga slutsatser behövs mer forskning för att klargöra sambandet mellan biokolens attribut och för att bestämma vilken samling egenskaper hos biokol som passar bäst för varje applikation. Hur storskalig skörd av vass kan påverka ekosystemet är fortfarande oklart. Det finns inte tillräckligt med forskning kring frågan för att kunna dra tydliga slutsatser. Detta beror på att det fin

The climate on earth keeps getting warmer where heat waves, eutrophication, rising sea levels, extreme weather like flooding, droughts and wildfires are an expanding problem. The focus of this bachelor thesis is to determine the potential of mitigating eutrophication and while contributing to blue growth by harvesting and make use of reeds like Phragmites australis and Arundo donax. Reeds have the ability to quickly absorb nutrients from aquatic environments and there are opportunities to use them as a feedstock for producing biochar to be potentially used in areas such as soil improvement, fodder additive and carbon sequestration. Additionally, optimal biochar properties for the observed applications gets analysed. The thesis is based on a systematic literature review and an interview with Niclas Anvret at the non-profit organisation “Race for the Baltic”. Results show that biochar produced according to parameters such as heating rate, biomass species and especially, different temperatures, results in varied characteristics that change the biochar's adsorption abilities, nutrient retention, alkalinity, stability, surface area and porosity volume. The different applications of biochar are, however, not easily determined. This is because of the fact that certain biochar properties, that are prominent in entirely different pyrolysis conditions, could both be beneficial for the same application. Additionally, the different attributes sometimes influence each other which gives rise to unclear patterns affecting use potential. To overcome these issues, more research is needed to clarify the correlations between attributes of the biochar and to determine which characteristics of biochar are best suited for each application. In terms of how large-scale harvesting of reed could affect the ecosystem is also unclear, there is not enough research regarding the question to be able to draw clear conclusions. The reasoning behind this is that there are knowledge gaps, geographi, Klimatet på jorden blir allt varmare och värmeböljor, övergödning, stigande havsnivåer, extrema väder som översvämningar, torka och bränder är ett stigande problem. Syftet med denna kandidatuppsats är att undersöka potentialen att mildra eutrofiering och samtidigt bidra till blå tillväxt genom att skörda - och använda sig av vass som Phragmites australis och Arundo donax. Vass har en framträdande förmåga att absorbera näringsämnen. Det finns därför möjligheter att använda dem som råvara för att producera biokol som potentiellt kan användas i områden såsom jordförbättring, fodertillsatser och kolbindning. Utöver detta undersöks optimala egenskaper för biokol enligt de observerade applikationerna. Kandidatuppsatsen bygger på en systematisk litteraturstudie och en intervju med Niclas Anvret på den ideella organisationen ”Race for the Baltic”. Resultaten indikerar att biokol, producerad i pyrolys enligt parametrar som uppvärmningshastighet, biomassa och i synnerhet olika temperaturer, resulterar i varierande egenskaper som förändrar biokolets absorptionsförmåga, bibehållande av näring, alkalinitet, stabilitet, ytarea och porositetsvolym. De olika tillämpningarna av biokol är emellertid svåra att avgöra på grund av vissa biokolegenskaper. Dessa egenskaper är framträdande under helt olika pyrolysförhållanden men kan samtidigt vara fördelaktiga för samma typ av applikation. Dessutom påverkar de olika attributen ibland varandra vilket ger upphov till komplexa trender som påverkar användningspotentialen. För att kunna dra tydliga slutsatser behövs mer forskning för att klargöra sambandet mellan biokolens attribut och för att bestämma vilken samling egenskaper hos biokol som passar bäst för varje applikation. Hur storskalig skörd av vass kan påverka ekosystemet är fortfarande oklart. Det finns inte tillräckligt med forskning kring frågan för att kunna dra tydliga slutsatser. Detta beror på att det fin

Eutrophication and climate change are major global problems. The sea weed Laminaria digitata and the reed Phragmites australis have the potential to absorb nutrients and CO2 during growth, as well as being a source of renewable energy in the form of biogas. The aim of this study was to evaluate Laminaria digitata and Phragmites australis concerning biogas production and nutrient recycling using a two-stage pilot scale process. The plant has a total volume of 430 L and consists of a hydrolysis bed and an up-flow anaerobic sludge blanket reactor (UASB). Two experiments were performed; one with Laminaria digitata as the sole substrate and one with a mixture of Laminaria digitata and Phragmites australis. Frozen substrates were placed in the hydrolysis bed and digestion was performed at 305 K during 70 days for Laminaria digitata and 100 days for the mixture of Laminaria digitata and Phragmites australis. The methane yield achieved was approximately 170 L kg−1 volatile substances (273.15 K, 101.3 kPa) in both experiments. These results suggest that Laminaria digitata can be efficiently digested in larger scale and has the potential to contribute to a future sustainable energy mix, considering its relatively high methane yield when anaerobically digested as the sole substrate. Digestion of Phragmites australis needs further development to make use of its full potential.

Eutrophication and climate change are major global problems. The sea weed Laminaria digitata and the reed Phragmites australis have the potential to absorb nutrients and CO2 during growth, as well as being a source of renewable energy in the form of biogas. The aim of this study was to evaluate Laminaria digitata and Phragmites australis concerning biogas production and nutrient recycling using a two-stage pilot scale process. The plant has a total volume of 430 L and consists of a hydrolysis bed and an up-flow anaerobic sludge blanket reactor (UASB). Two experiments were performed; one with Laminaria digitata as the sole substrate and one with a mixture of Laminaria digitata and Phragmites australis. Frozen substrates were placed in the hydrolysis bed and digestion was performed at 305 K during 70 days for Laminaria digitata and 100 days for the mixture of Laminaria digitata and Phragmites australis. The methane yield achieved was approximately 170 L kg−1 volatile substances (273.15 K, 101.3 kPa) in both experiments. These results suggest that Laminaria digitata can be efficiently digested in larger scale and has the potential to contribute to a future sustainable energy mix, considering its relatively high methane yield when anaerobically digested as the sole substrate. Digestion of Phragmites australis needs further development to make use of its full potential.

Eutrophication and climate change are major global problems. The sea weed Laminaria digitata and the reed Phragmites australis have the potential to absorb nutrients and CO2 during growth, as well as being a source of renewable energy in the form of biogas. The aim of this study was to evaluate Laminaria digitata and Phragmites australis concerning biogas production and nutrient recycling using a two-stage pilot scale process. The plant has a total volume of 430 L and consists of a hydrolysis bed and an up-flow anaerobic sludge blanket reactor (UASB). Two experiments were performed; one with Laminaria digitata as the sole substrate and one with a mixture of Laminaria digitata and Phragmites australis. Frozen substrates were placed in the hydrolysis bed and digestion was performed at 305 K during 70 days for Laminaria digitata and 100 days for the mixture of Laminaria digitata and Phragmites australis. The methane yield achieved was approximately 170 L kg−1 volatile substances (273.15 K, 101.3 kPa) in both experiments. These results suggest that Laminaria digitata can be efficiently digested in larger scale and has the potential to contribute to a future sustainable energy mix, considering its relatively high methane yield when anaerobically digested as the sole substrate. Digestion of Phragmites australis needs further development to make use of its full potential.

Eutrophication and climate change are major global problems. The sea weed Laminaria digitata and the reed Phragmites australis have the potential to absorb nutrients and CO2 during growth, as well as being a source of renewable energy in the form of biogas. The aim of this study was to evaluate Laminaria digitata and Phragmites australis concerning biogas production and nutrient recycling using a two-stage pilot scale process. The plant has a total volume of 430 L and consists of a hydrolysis bed and an up-flow anaerobic sludge blanket reactor (UASB). Two experiments were performed; one with Laminaria digitata as the sole substrate and one with a mixture of Laminaria digitata and Phragmites australis. Frozen substrates were placed in the hydrolysis bed and digestion was performed at 305 K during 70 days for Laminaria digitata and 100 days for the mixture of Laminaria digitata and Phragmites australis. The methane yield achieved was approximately 170 L kg−1 volatile substances (273.15 K, 101.3 kPa) in both experiments. These results suggest that Laminaria digitata can be efficiently digested in larger scale and has the potential to contribute to a future sustainable energy mix, considering its relatively high methane yield when anaerobically digested as the sole substrate. Digestion of Phragmites australis needs further development to make use of its full potential.

Eutrophication and climate change are major global problems. The sea weed Laminaria digitata and the reed Phragmites australis have the potential to absorb nutrients and CO2 during growth, as well as being a source of renewable energy in the form of biogas. The aim of this study was to evaluate Laminaria digitata and Phragmites australis concerning biogas production and nutrient recycling using a two-stage pilot scale process. The plant has a total volume of 430 L and consists of a hydrolysis bed and an up-flow anaerobic sludge blanket reactor (UASB). Two experiments were performed; one with Laminaria digitata as the sole substrate and one with a mixture of Laminaria digitata and Phragmites australis. Frozen substrates were placed in the hydrolysis bed and digestion was performed at 305 K during 70 days for Laminaria digitata and 100 days for the mixture of Laminaria digitata and Phragmites australis. The methane yield achieved was approximately 170 L kg−1 volatile substances (273.15 K, 101.3 kPa) in both experiments. These results suggest that Laminaria digitata can be efficiently digested in larger scale and has the potential to contribute to a future sustainable energy mix, considering its relatively high methane yield when anaerobically digested as the sole substrate. Digestion of Phragmites australis needs further development to make use of its full potential.

Evaluation of trace metal pollution in an environmentally complex context may require the use of a suite of indicators. Common reed, Phragmites australis, is a well-known biomonitor of sediment pollution. Here, we show its potential for also assessing air pollution. The plant panicles, holding silky hairs with high surface to volume ratio, are appropriate collectors of atmospheric contaminants, which perform independently from root bioconcentration. We applied the dual value of common reed as an indicator of trace metal pollution to the case of a chlor-alkali plant in the Ebro river bank (Spain). This factory had historically damped waste to the shallow Flix reservoir. Extensive common reed meadows are growing on the top of the waste, in a nearby nature reserve across the reservoir and a meander immediately downriver. Three replicated individuals from a total of 11 sites were sampled, and the trace metal content measured in the main plant compartments (roots, rhizomes, stems, leaves, and panicles). Panicles and roots showed a much larger concentration of trace metals than the other plant compartments. Levels of Hg, Cu, and Ni were markedly higher in panicles at the factory and nearby points of the reserve and lowered at the meander. In contrast, Cd, Zn, and Mn in roots increased from the factory to the meander downriver. We conclude that panicles show recent (less than a year) airborne pollution, whereas roots indicate the long-term transport of pollutants from the waste in the shoreline of the factory to downriver sedimentation hotspots, where they become more bioavailable than in the factory waste. The Hg spatial patterns in panicles agree with air measurements in later years, therefore, confirming the panicles suitability for assessing airborne pollution and, consequently, Phragmites as a potential dual biomonitor of air and sediments.

There is a growing interest about the possibility of exploiting the local biomass as an energy source. The main resource for biofuel production in Latvia is wood. Water plants, like common reed, growing in nearly all of the water reservoirs in Latvia, and all cultivate plants and residues of cereal crops, also can be good alternative for solid bio fuels production. The aim of this paper is to analyze possibilities to make composite fuels from these recourses. The study reveals research of ash content and highest burning heat value in different composite biomass fuels. It contains analysis of samples obtained from various local Latvian biomass types, i.e. reed, wood, flax spray, hay, hemp and peat, by combining them in different proportions. The study contains optimal combining proportions of different biomass types for composite fuel production basing on the ash content and burning heat in them. The results of the study show that the value of wood highest burning heat is higher than another biomass types like reed, peat, hay, hemp and flax spray. It means that combining of different biomass types with wood, will reduce the calorific value of composite biomass. Also, wood is a fuel with a low ash content, and admixture of various biomass types available in Latvia, as well as admixture of coal dust to the wood in composite duels, increases ash content in the respective fuels. In order to increase the burning heat and decrease ash content value to the optimal level and to diversify raw materials necessary for biomass fuel generating process, the authors analyze possibilities of using composite fuels by combining wood and coal dust.

There is a growing interest about the possibility of exploiting the local biomass as an energy source. The main resource for biofuel production in Latvia is wood. Water plants, like common reed, growing in nearly all of the water reservoirs in Latvia, and all cultivate plants and residues of cereal crops, also can be good alternative for solid bio fuels production. The aim of this paper is to analyze possibilities to make composite fuels from these recourses. The study reveals research of ash content and highest burning heat value in different composite biomass fuels. It contains analysis of samples obtained from various local Latvian biomass types, i.e. reed, wood, flax spray, hay, hemp and peat, by combining them in different proportions. The study contains optimal combining proportions of different biomass types for composite fuel production basing on the ash content and burning heat in them. The results of the study show that the value of wood highest burning heat is higher than another biomass types like reed, peat, hay, hemp and flax spray. It means that combining of different biomass types with wood, will reduce the calorific value of composite biomass. Also, wood is a fuel with a low ash content, and admixture of various biomass types available in Latvia, as well as admixture of coal dust to the wood in composite duels, increases ash content in the respective fuels. In order to increase the burning heat and decrease ash content value to the optimal level and to diversify raw materials necessary for biomass fuel generating process, the authors analyze possibilities of using composite fuels by combining wood and coal dust.

In Latvia the total renewable energy resource volume has not been fully evaluated. Reed exploitation for energy output has not been developed on a large scale. One of the factors for this is the lack of information about to reed resource spread and characteristics. Therefore, there arises the need for a united inventory system – the formation of a reed cadaster. The study contains information on basic principles of reed cadastre creation and research methodologies. The reed cadaster is a list of the reed researches which contains information about the reed areas in Latvia, the volume and locations, the legal status, possibilities for exploitation, as well as the biomass qualities, in each specific water reservoir. For each water reservoir, which is included in the reed cadaster, a certificate and chart have been produced. Information about the reed locations in each specific lake have been shown on the cadaster chart; the boundaries of the water reservoir, the boundaries of the reed plants and areas, the natural habitat protected area boundaries, the district boundaries, as well as the access roads. The data for reed characteristics and accessible volumes is compiled in the water reservoir cadaster passport. Development for reed exploitation in the conditions of Latvia is dependent on the location, accessible volumes and existing infrastructure. Reeds are a long term renewable energy resource, with the spread of reeds increasing every year.

The study reveals research of ash content in different composite biomass fuels. It contains analysis of samples obtained from various local Latvian biomass types, i.e. reed, wood, hemp, flax shives and peat, by combining them in different proportions. Ash is a by-product derived from combustion process consisting mostly of inorganic substances that are left after a fuel is burnt. High level of ash content in a fuel is undesirable because it causes problems in automation of biomass combustion process. Previous studies carried out by the author show that average ash content in reeds is 2%, which is a high index comparing with wood where ash content is approximately 0,5-1%. Thus, the high ash content in reeds my cause problems in reed combustion in solid fuel boilers. Besides, it is not possible to ensure permanent reed collection that would ensure continuous reed fuel generating process all year long. In order to reduce the ash content to the optimal level and to diversify raw materials necessary for biomass fuel generating process, the author suggests using composite fuels by combining different biomass types. The study contains optimal combining proportions of different biomass types for composite fuel production basing on the ash content in them.

In Latvia the total renewable energy resource volume has not been fully evaluated. Reed exploitation for energy output has not been developed on a large scale. One of the factors for this is the lack of information about to reed resource spread and characteristics. Therefore, there arises the need for a united inventory system – the formation of a reed cadaster. The study contains information on basic principles of reed cadastre creation and research methodologies. The reed cadaster is a list of the reed researches which contains information about the reed areas in Latvia, the volume and locations, the legal status, possibilities for exploitation, as well as the biomass qualities, in each specific water reservoir. For each water reservoir, which is included in the reed cadaster, a certificate and chart have been produced. Information about the reed locations in each specific lake have been shown on the cadaster chart; the boundaries of the water reservoir, the boundaries of the reed plants and areas, the natural habitat protected area boundaries, the district boundaries, as well as the access roads. The data for reed characteristics and accessible volumes is compiled in the water reservoir cadaster passport. Development for reed exploitation in the conditions of Latvia is dependent on the location, accessible volumes and existing infrastructure. Reeds are a long term renewable energy resource, with the spread of reeds increasing every year.

North American freshwater species are facing an extraordinarily high rate of extinction due to numerous anthropogenic influences. Pecos assiminea (Assiminea pecos) is an endangered, semi-aquatic snail endemic to two spring systems located in eastern New Mexico and west Texas. Basic biological information needed for effective monitoring and conservation is currently lacking for this species. My objectives were to determine the habitat use patterns, evaluate the effects of the removal of common reed (Phragmites australis) on habitat use, compare the relative effectiveness of two survey methodologies, and conduct an empirical study to assess the environmental and observer factors influencing the detection probability of Pecos assiminea, at Bitter Lake National Wildlife Refuge in New Mexico. Pecos assiminea sampling occurred during 2013-2015 (nsurveys = 11). Surveys were conducted at two locations, Sinkhole 31 and Bitter Creek using two methods, standard quadrats (n = 528) and weathered wooden tiles left on the substrate (n = 671). Snails were identified and counted, and a suite of habitat variables were collected at each sampling point. In addition, empty phantom springsnail (Pyrgulopsis texana) shells were used as a surrogate for Pecos assiminea to empirically assess detection probability. A total of 0-9 shells were placed in each quadrat (n = 12). Shells were placed in microhabitats where Pecos assiminea is typically found, and 10 observers with varying experience levels searched through the quadrats for 5 minutes each. The results from quadrat survey classification trees suggested that Pecos assiminea presence was associated with general features relating to moisture and temperature, however, the availability and quality of suitable Pecos assiminea habitat differed between Bitter Creek and Sinkhole 31. These differences seemed to be reflected by a larger population of Pecos assiminea at Sinkhole 31. The removal of common reed was expected to allow native vegetation

The study shows results of research on heavy metals concentration in biomass of common reed, hemp and Reed canary grass. The research of common reed was performed during winter period from 2010 until 2012 in 11 natural and artificial water bodies of Latvia. For the harvested biomass in the spring of 2009 and 2010, hemp and reed canary grass samples were investigated.For the collected common reed samples the heavy metal content (Cd, Pb, Cu, Ni, Fe) was established in the biomass. For the hemp and reed canary grass samples, Cd and Pb content were established in the biomass. On the basis of the findings of this research, the suitability of the plant biomass for energy production was analyzed.The heavy metal content in the common reed biomass is suitable for the requirements of solid biofuel. Common reed from all the reed beds of the Latgale (region of Latvia) can be collected in one place and used for the production of fuel. The removal of common reed will help to reduce the heavy metal content in the natural waters and sediment of the reed beds.In the hemp and reed canary grass samples the heavy metals were ascertained periodically. It was found that in some of the research samples they exceeded the MAC for fuel.

The paper shows the results obtained during the research of reed dynamics revealing that in Eastern Latvia 20 lakes and pisciculture farms are potentially important for the reed extraction. In 2008, the reed resources there covered a territory of approximately 2300 ha. The ortophoto images of potentially important water bodies made in 1997, 2005 and 2008 were analyzed using the computer program ArcMap. The reed growth develops differently in every water body, but in general the eutrophication of water bodies and the enlargement of reed-covered areas can be observed. The most rapidly the reed occupies new territories in pisciculture farms and shallow lakes. The analysis of reed resource dynamics show that reed-covered areas in this region are expanding every year. The main factors that influence the distribution of reed growths refer to human activities, climatic conditions, hydrological regime in water bodies and natural processes of eutrophication.

The study shows results of research on reed productivity and on factors influencing this productivity. The research was performed during winter period from 2010 until 2012 in 23 natural and artificial water bodies of Latvia. The author of this study analyzed indexes of reed growth productivity and found regularities that statistically significantly (p less then 0,05) explain changes of reed productivity in water bodies depending on individual reed growing conditions in each water body. It is established that the productivity of reed growth depends on the amount of nutrients in the water of water body and that this productivity rises if the total concentration of nitrogen and phosphorus in the water is increased. The reed productivity is lower in clearer water. This parameter may be used in order to evaluate the amount of extractable biomass. The coherence is characterized by statistically significant (p less then 0,05) regression equation.

The paper shows the results obtained during the research of reed dynamics revealing that in Eastern Latvia 20 lakes and pisciculture farms are potentially important for the reed extraction. In 2008, the reed resources there covered a territory of approximately 2300 ha. The ortophoto images of potentially important water bodies made in 1997, 2005 and 2008 were analyzed using the computer program ArcMap. The reed growth develops differently in every water body, but in general the eutrophication of water bodies and the enlargement of reed-covered areas can be observed. The most rapidly the reed occupies new territories in pisciculture farms and shallow lakes. The analysis of reed resource dynamics show that reed-covered areas in this region are expanding every year. The main factors that influence the distribution of reed growths refer to human activities, climatic conditions, hydrological regime in water bodies and natural processes of eutrophication.

Introduced Phragmites australis is rapidly spreading in North America, threatening wetland plant communities and endemic native genotypes (Phragmites australis americanus). Lack of successful long-term control resulted in initiation of biological control research. In the past, the program targeting introduced Phragmites has focused on several promising potential biological control agents with large impacts on P. australis. The purpose of this report is to: (1) identify potential agents for in-depth study; (2) outline and report initial testing procedures and results of host-specificity studies of identified agents; (3) assess possibilities to develop laboratory/greenhouse mass-rearing procedures; (4) outline approaches for long-term monitoring at pre-release sites; and (5) assess the extent of hybridization between native and introduced genotypes. All selected insect species are stem miners that overwinter as eggs, with larvae feeding in spring and early summer. Host specificity testing is being conducted in a Rhode Island quarantine facility and at the Center for Agricultural Bioscience International (CABI) in Switzerland. In addition, investigations continue on the impact of Phragmites populations on native fauna and flora as well as the economic and ecological effects of Phragmites invasion. Hybridization between native and introduced genotypes appears to be restricted to a single hybridization event in central New York State., The original document contains color images.

Doktorska disertacija je obuhvata ispitivanje metala i organskih jedinjenja u ekosistemu reke Tise. Istraţivanja su obavljena od septembra do novembra 2010. godine. Doktorska disertacija je omogućila definisanje: intenziteta antropogenog uticaja na savremene sedimente reke Tise kroz povišen sadrţaj teških metala; sastava organske supstance sedimenata reke Tise; razlika između organa riba u prosečnoj vrednosti koncentracije metala; razlika između ekosistemski različitih vrsta riba u prosečnoj vrednosti koncentracije metala; razlika između organa trske u prosečnoj vrednosti koncentracije metala. Na osnovu postavljenih zadataka i cilja istraţivanja došlo se do sledećih rezultata. Rezultati granulometrijskih ispitivanja pokazali su da uzorci iz pritoka i donjeg toka reke pripadaju peskovito-glinovitim alevritima, uzorci iz srednjeg toka – glinovito-peskovitim alevritima, a iz gornjeg toka nalaze se na prelazu između peskovitih i glinovitih alevrita. Prema trokomponentnom dijagramu halkofilni – litofilni – lantanoidi jasno je uočljivo pomeranje ispitivanih uzoraka ka roglju halkofilnih elemenata, čime se naglašava i ističe povišenje sadrţaja ovih mikroelemenata u odnosu na referentne uzorke iz bušotina za koje se sa sigurnošću zna da su bez ikakvih antropogenih uticaja. Sadrţaj ukupne i rastvorne organske materije je uniforman u svim uzorcima. Svi uzorci imaju skoro identičnu raspodelu n-alkana, sterana, tricikličnih i pentacikličnih terpana, što ukazuje na isto poreklo organske materije. Maksimum n-alkana na n-C27 ili na n-C29 sa dominacijom neparnih članova u opsegu n-C23 – n-C35 ukazuje na prisustvo nezrele nativne organske materije terestrijalnog porekla. Na osnovu prisustva terpana i sterana u alkanskim frakcijama sedimenata sa raspodelama biolipidnih i geolipidniih stabilnijih izomera kakve se mogu naći u nafti, moţe se zaključiti da je u ispitivanim uzorcima prisutna i organska supstanca naftnog tipa. Koncentracije metala u različitim organima ribe iz reke Tise ra, This PhD dissertation presents the analysis of the metals and organic compounds in the ecosystem of the Tisza River. The researches were conducted in the period from September to November 2010. The PhD dissertation provides defining of: anthropogenic impact on contemporary sediments through increased level of heavy metals concentration; the composition of the organic substance of the sediments of the Tisza River; the difference in the organs of fish with regard to bioaccumulation of metals; the difference in the fish species with regard to bioaccumulation of metals; the difference in the organs of a common reed with regard to bioaccumulation of metals. On the basis of the set aims and objectives of the research, the following results are obtained. The results of granulometric analyses show that the samples taken from the tributaries and the lower sections of the river belong to sandy-clay silt; the samples from the middle section of the river belong to clay-sandy silt, while those taken from the upper section of the river are on the classification borderline being between sandy and clay silt. According to the ternary diagram for chalcophile-lithophile-lanthanides, it is apparent that there is a shift of the analyzed samples towards the apex of the chalcophile elements. Defining the composition of the organic substance of sediments of the Tisza River and its origin both in terms of source and its autochthonous or allochthonous features, the presence of immature native organic matter of terrestrial origin is determined, as well as the presence of organic substances of petroleum type. Metals bioaccumulated in various organs of fish in different concentrations. A liver and gills are the most affected organs in terms of bioaccumulation. Also, metals bioaccumulate in different concentrations in different fish species. The analyzed elements have statistically significant higher bioaccumulation in carp than in bream, sterlet and pike. The accumulated metals in a common reed

Doktorska disertacija je obuhvata ispitivanje metala i organskih jedinjenja u ekosistemu reke Tise. Istraţivanja su obavljena od septembra do novembra 2010. godine. Doktorska disertacija je omogućila definisanje: intenziteta antropogenog uticaja na savremene sedimente reke Tise kroz povišen sadrţaj teških metala; sastava organske supstance sedimenata reke Tise; razlika između organa riba u prosečnoj vrednosti koncentracije metala; razlika između ekosistemski različitih vrsta riba u prosečnoj vrednosti koncentracije metala; razlika između organa trske u prosečnoj vrednosti koncentracije metala. Na osnovu postavljenih zadataka i cilja istraţivanja došlo se do sledećih rezultata. Rezultati granulometrijskih ispitivanja pokazali su da uzorci iz pritoka i donjeg toka reke pripadaju peskovito-glinovitim alevritima, uzorci iz srednjeg toka – glinovito-peskovitim alevritima, a iz gornjeg toka nalaze se na prelazu između peskovitih i glinovitih alevrita. Prema trokomponentnom dijagramu halkofilni – litofilni – lantanoidi jasno je uočljivo pomeranje ispitivanih uzoraka ka roglju halkofilnih elemenata, čime se naglašava i ističe povišenje sadrţaja ovih mikroelemenata u odnosu na referentne uzorke iz bušotina za koje se sa sigurnošću zna da su bez ikakvih antropogenih uticaja. Sadrţaj ukupne i rastvorne organske materije je uniforman u svim uzorcima. Svi uzorci imaju skoro identičnu raspodelu n-alkana, sterana, tricikličnih i pentacikličnih terpana, što ukazuje na isto poreklo organske materije. Maksimum n-alkana na n-C27 ili na n-C29 sa dominacijom neparnih članova u opsegu n-C23 – n-C35 ukazuje na prisustvo nezrele nativne organske materije terestrijalnog porekla. Na osnovu prisustva terpana i sterana u alkanskim frakcijama sedimenata sa raspodelama biolipidnih i geolipidniih stabilnijih izomera kakve se mogu naći u nafti, moţe se zaključiti da je u ispitivanim uzorcima prisutna i organska supstanca naftnog tipa. Koncentracije metala u različitim organima ribe iz reke Tise ra, This PhD dissertation presents the analysis of the metals and organic compounds in the ecosystem of the Tisza River. The researches were conducted in the period from September to November 2010. The PhD dissertation provides defining of: anthropogenic impact on contemporary sediments through increased level of heavy metals concentration; the composition of the organic substance of the sediments of the Tisza River; the difference in the organs of fish with regard to bioaccumulation of metals; the difference in the fish species with regard to bioaccumulation of metals; the difference in the organs of a common reed with regard to bioaccumulation of metals. On the basis of the set aims and objectives of the research, the following results are obtained. The results of granulometric analyses show that the samples taken from the tributaries and the lower sections of the river belong to sandy-clay silt; the samples from the middle section of the river belong to clay-sandy silt, while those taken from the upper section of the river are on the classification borderline being between sandy and clay silt. According to the ternary diagram for chalcophile-lithophile-lanthanides, it is apparent that there is a shift of the analyzed samples towards the apex of the chalcophile elements. Defining the composition of the organic substance of sediments of the Tisza River and its origin both in terms of source and its autochthonous or allochthonous features, the presence of immature native organic matter of terrestrial origin is determined, as well as the presence of organic substances of petroleum type. Metals bioaccumulated in various organs of fish in different concentrations. A liver and gills are the most affected organs in terms of bioaccumulation. Also, metals bioaccumulate in different concentrations in different fish species. The analyzed elements have statistically significant higher bioaccumulation in carp than in bream, sterlet and pike. The accumulated metals in a common reed

Eutrophication combined with climate change has caused ephemeral filamentous macroalgae to increase and drifts of seaweed cover large areas of some Baltic Sea sites during summer. In ongoing projects, these mass occurrences of drifting filamentous macroalgae are being harvested to mitigate eutrophication, with preliminary results indicating considerable nutrient reduction potential. In the present study, an energy assessment was made of biogas production from the retrieved biomass for a Baltic Sea pilot case. Use of different indicators revealed a positive energy balance. The energy requirements corresponded to about 30%-40% of the energy content in the end products. The net energy gain was 530-800 MJ primary energy per ton wet weight of algae for small-scale and large-scale scenarios, where 6 000 and 13 000 tonnes dwt were harvested, respectively. However, the exergy efficiency differed from the energy efficiency, emphasising the importance of taking energy quality into consideration when evaluating energy systems. An uncertainty analysis indicated parametric uncertainty of about 25%-40%, which we consider to be acceptable given the generally high sensitivity of the indicators to changes in input data, allocation method, and system design. Overall, our evaluation indicated that biogas production may be a viable handling strategy for retrieved biomass, while harvesting other types of macroalgae than red filamentous species considered here may render a better energy balance due to higher methane yields., QC 20140404

The Langenreichenbach ecotechnology research facility contains 15 individual pilot-scale treatment systems of eight different designs or operational variants. The designs differ in terms of flow direction, degree of media saturation, media type, loading regime, and aeration mechanism. Seven systems were constructed as planted and unplanted pairs, in order to elucidate the role of common reed (Phragmites australis) in these technologies. The facility is unique in the fact that it is located adjacent to the wastewater treatment plant for the nearby village, enabling all of the pilot-scale systems to receive the same wastewater. The construction of the Langenreichenbach research facility is placed within the overarching discipline of ecological engineering. An overview of the treatment wetland design spectrum (ranging from passive to highly intensified designs) is discussed and the specific designs implemented at Langenreichenbach are presented in detail, along with the internal sampling methods for both saturated and unsaturated systems.

Methodology and results of common reed reproductive characteristics investigation in water bodies with different level of radionuclide contamination are represented in the work. The aim of the work is to study peculiarities of response of higher aquatic plants, by the example of the common reed, on long-term ionizing radiation exposure at genetic, morphological and reproductive levels. The matter of research is a generative reproduction and growth processes of the common reed under conditions of ionizing radiation stress. The research was carried out with the use of laboratorial seeds cultivating method. Doses absorbed by plants were assessed with the help of methodology using dose conversion coefficients. The obtained research data about liability and abnormalities of common reed’s germs in water bodies with different level of radionuclide contamination testify about considerably high level of low doses long-term exposure efficiency for indexes of germination and germinating ability of seeds

Constructed wetlands are largely used for water treatment both in agricultural land and for treating water from municipal and industrial waste. These wetlands need to be managed in order to work properly. How to deal with the large amount of vegetation harvested in the wetlands has withdrawn a great concern. The application of using wetland biomass as the co-substrates in anaerobic digestion was studied in this project. Plant materials, mostly Phragmites australis (common reed) from three different wetlands were used as raw material to produce biogas. The methane production using reed material harvested from municipal wastewater, industrial wastewater and an agricultural wetland are 66, 106, 144 ml/g VS respectively, which were lower than the suggested number 180ml/g VS. The gas potential remains a lot to be improved such as harvesting at summer to reduce the lignin content and changing the co-digestion mixing level to adjust to the optimal C/N ratio. Chemical analyses were performed concerning the gas yield and the residue quality. The digested residues showed a low concentration of cadmium, providing a non-toxic possibility to be spread on farm land as fertilizers, and closing the nutrient circle from land into water and back to land again. Pretreatments in the biogas process are usually focusing on the reduction of the lignocellulosic content in the raw material. Assessment of costs and benefits is needed for using wetland reed in the biogas production and applying any pretreatment methods.

Constructed wetlands are largely used for water treatment both in agricultural land and for treating water from municipal and industrial waste. These wetlands need to be managed in order to work properly. How to deal with the large amount of vegetation harvested in the wetlands has withdrawn a great concern. The application of using wetland biomass as the co-substrates in anaerobic digestion was studied in this project. Plant materials, mostly Phragmites australis (common reed) from three different wetlands were used as raw material to produce biogas. The methane production using reed material harvested from municipal wastewater, industrial wastewater and an agricultural wetland are 66, 106, 144 ml/g VS respectively, which were lower than the suggested number 180ml/g VS. The gas potential remains a lot to be improved such as harvesting at summer to reduce the lignin content and changing the co-digestion mixing level to adjust to the optimal C/N ratio. Chemical analyses were performed concerning the gas yield and the residue quality. The digested residues showed a low concentration of cadmium, providing a non-toxic possibility to be spread on farm land as fertilizers, and closing the nutrient circle from land into water and back to land again. Pretreatments in the biogas process are usually focusing on the reduction of the lignocellulosic content in the raw material. Assessment of costs and benefits is needed for using wetland reed in the biogas production and applying any pretreatment methods.

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There is little information about the effect of wetland plants on N turnover and N gas emission (N2O, N2) in recently reflooded minerotrophic mires (fens). We carried out lab model experiments with two typical wetland plants, reed canary grass (Phalaris arundinacea L.) and common reed (Phragmites australis (Cav.) Trin. ex Steud.) on fen peat substrate using the 15N gas flux method. The reflooded fen peat substrate and the tested plants influenced the amount of gaseous N losses, its composition, and the way of its emission from the peat substrate to the atmosphere in a differentiated manner. Irrespective of plants the denitrification losses were between 49.9 to 74.5 % of the applied N. Whereas common reed narrowed the ratio between N2 and N2O up to 11:1, red canary grass caused a strong expansion of this ratio up to 343:1. The denitrification N gas liberation through the shoots of reed canary grass was not significant. In case of common reed approx. 20% of the fertiliser derived N2 and approx. 10% of the fertiliser derived N2O were exhaled by the plants.

There is little information about the effect of wetland plants on N turnover and N gas emission (N2O, N2) in recently reflooded minerotrophic mires (fens). We carried out lab model experiments with two typical wetland plants, reed canary grass (Phalaris arundinacea L.) and common reed (Phragmites australis (Cav.) Trin. ex Steud.) on fen peat substrate using the 15N gas flux method. The reflooded fen peat substrate and the tested plants influenced the amount of gaseous N losses, its composition, and the way of its emission from the peat substrate to the atmosphere in a differentiated manner. Irrespective of plants the denitrification losses were between 49.9 to 74.5 % of the applied N. Whereas common reed narrowed the ratio between N2 and N2O up to 11:1, red canary grass caused a strong expansion of this ratio up to 343:1. The denitrification N gas liberation through the shoots of reed canary grass was not significant. In case of common reed approx. 20% of the fertiliser derived N2 and approx. 10% of the fertiliser derived N2O were exhaled by the plants.

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The regularities of heavy metals (Fe, Cu, Zn, Cd, Pb) and arsenic accumulation in various types of aquatic vegetation have been studied, depending on the season and the levels of pollution of the Srepok River (Vietnam). It has been found that the concentrations of Fe, Cu, Zn, As, Cd and Pb in all studied areas of the river in the roots of water hyacinth and common reed were higher than those in the stems. It has been shown that the content of toxicants in plants varied widely, depending on the level of pollution in the adjacent area. The maximum concentrations of Cu, Zn and Pb were noted in the organs of the water hyacinth and reeds in the lands within the industrial areas, and the highest levels of As and Cd were noted up the stream, before the river entrance into the industrial area. The content of Fe in all areas remained stable. The difference in heavy metals’ concentrations in plants close to the banks in the provinces and in the middle of the river in most cases was not statistically significant. © 2018, Pharmainfo Publications. All rights reserved.