Thèses : « A. donax »

1

Pereira, Fernanda Carina Gonçalves. « Gestão de cana (Arundo donax) em zonas ribeirinhas do Algarve ». Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/3909.

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Fatunwase, Akintayo. « Simple Pretreatment of Arundo Donax and Enzymatic Hydrolysis of Cellulosic Materials ». Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/163.

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Arundo donax (Giant reed Plant) contains high level of cellulose, hemicellulose and lignin. It is used as a second generation method for the production of ethanol from lignocellulosic biomasses. Cellulose molecules comprised an unbranched polymer of 1,000 to 1,000,000 D-glucose linking units coupled with beta-1, 4 glycosidic bonds. Microorganism present in beta 1-4 gluconase breaks down the glucosidic linkage in the Microcrystalline structure of the cellulose to cellobiose molecules (a glucose dimer have a beta-1, 4 bond). The cellobiose is subsequently broken down into glucose molecules by an enzyme called beta-glucosidase. The scope of this work entails hydrolysis conversion of cellulose to glucose and other value added products using enzymatic (Cellulase)

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Owoyomi, Olumuyiwa A. « Eradication of the giant reed (arundo donax) : an evaluation of different methodologies ». Scholarly Commons, 2009. https://scholarlycommons.pacific.edu/uop_etds/714.

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The invasion of riparian habitats by the exotic plant, Arundo donax L., commonly known as the giant reed is one of the greatest threats to ecosystems in Central and Southern California. There have been several efforts to eradicate this plant with varying control methods. This study evaluated some previously known techniques of controlling the giant reed in addition to some novel methodologies to determine the most effective approach. The study site is a section of the Lower Calaveras River that transects University of the Pacific's campus and is a prime example of the devastation caused by the giant reed. The project site was cut and cleared over a period of eight months and divided into fourteen plots. Seven different techniques including a control were selected and each treatment was randomly applied to two plots. The methods chosen were: "cut, resprout and spray", "cut-stem, spray", "chip and compost", "chip and tarp", "compost" and "compost and tarp". The response variables were the "mean regrowth height", "mean circumference of stalks" and the "number of resprouted stalks". A repeated measures ANOVA was used to analyze the response variables. The "compost and tarp" method had the lowest number of resprouted stalks and was also significantly different from the control treatment. None of the other techniques were significantly different from the control but the "compost" method showed some promise. Based on this study, the "compost and tarp" technique is the most effective treatment. The data collection for this study was limited and future experiments should be conducted on a longer time scale to assess the effectiveness of these methods. Further research should also be conducted to evaluate the effectiveness of various biotic factors on the growth of A. donax, which could enhance the efficacy of methodologies currently used to control this introduced invasive plant.

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Lemões, Juliana Silva. « Produção de etanol de segunda geração a partir de arundo donax L ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/179650.

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A crescente demanda energética traz a necessidade de desenvolvimento de novos combustíveis renováveis, visando à menor emissão de partículas e poluentes ao meio ambiente e a substituição dos derivados de petróleo. Atualmente, pesquisas com a utilização de biomassa lignocelulósica vêm sendo desenvolvidas com o objetivo de tornar o processo de produção de etanol de segunda geração economicamente viável. O arundo (Arundo donax L.) é uma gramínea de crescimento rápido, alto rendimento de biomassa e pode ser cultivada em áreas marginais, que em função de características de cultivo, crescimento e produtividade apresenta potencial para produção de etanol de segunda geração. O presente trabalho teve como objetivo estabelecer as melhores condições de pré-tratamento, hidrólise e fermentação da biomassa de Arundo donax L. visando à produção de etanol. Três pré-tratamentos foram testados: pré-tratamento ácido, pré-tratamento ácido seguido de pré-tratamento alcalino e pré-tratamento alcalino. Foram avaliadas variáveis de cada pré-tratamento utilizando planejamento composto central rotacional através da metodologia de superfície de resposta Após a otimização das condições de pré-tratamento, foram avaliadas as variáveis carga enzimática e relação sólido:líquido nos rendimentos de glicose e xilose na hidrólise enzimática. Por fim, foram avaliadas condições de fermentação dos hidrolisados obtidos na hidrólise enzimática e fermentação e hidrólise simultâneas da biomassa pré-tratada. No pré-tratamento da biomassa as concentrações de glicose e xilose liberadas na hidrólise enzimática da biomassa pré-tratada, apenas com ácido sulfúrico, variaram de 6,2 a 19,1 g L-1 e 1,8 a 3,1 g L-1, respectivamente. A adição de pré-tratamento alcalino possibilitou aumento significativo da concentração de açúcares liberados. O uso apenas de pré-tratamento alcalino resultou em concentrações de glicose e xilose que não diferiram estatisticamente dos obtidos com pré-tratamento em duas etapas. As concentrações de 5-hidroximetilfurfural e furfural não diferiram significativamente entre os pré-tratamentos testados. Na hidrólise enzimática apenas a relação sólido:líquido apresentou efeito significativo nas concentrações de glicose e xilose. Os rendimentos de etanol obtidos pelo processo de sacarificação e fermentação simultâneas foram superiores aos obtidos quando a hidrólise e fermentação foram conduzidas em etapas separadas. Os maiores rendimentos de etanol foram obtidos com carga de sólidos de 200 g L-1, e 25 FPU g-1 na etapa de pré-hidrólise.
The growing energy demand brings the need for development of new renewable fuels, aiming to reduceemission of particles and pollutants into the environment as well as substitution of petroleum products. Nowadays, researches using lignocellulosic biomass have been developed with the objective of making the production process of second generation ethanol economically viable. Arundo donax L., is a perennial grass presenting high biomass production and ability of growing in different environments, which due to the cultivation characteristics, growth and productivity presents potential as raw material for production of second generation ethanol. The present work envisages to establish the best pre-treatment hydrolysis and fermentation conditions for the biomass of Arundo donax L. aiming to ethanol production. Three pretreatments were tested: acid pretreatment, acid pretreatment followed by alkaline pretreatment and alkaline pretreatment. Variables of each pretreatment were evaluated using central rotational composite design through response surface methodology.After optimization of the pretreatment conditions, the influence of enzymatic loading and solid-to-liquid ratio variables in the glucose and xylose yields by the enzymatic hydrolysis were evaluated. Finally, the fermentation conditions of the hydrolysates obtained in the enzymatic hydrolysis and simultaneous fermentation and hydrolysis of the pretreated biomass were evaluated The amounts of glucose and xylose released by enzymatic hydrolysis of the Arundo biomass obtained from acid pretreatment ranged from 6.2 to 19.1 g/L and 1.8 to 3.1 g/L, respectively. The addition of an alkaline pretreatment led to a higher yield from the enzymatic hydrolysis with the average glucose concentration 3.5 times that obtained after biomass hydrolysis with an acid pretreatment exclusively. The use of an alkaline pretreatment alone resulted in glucose and xylose concentrations similar to those obtained in the two-step pretreatment: acid pretreatment followed by alkaline pretreatment. There was no significant difference in 5-hydroxymethylfurfural, furfural or acetic acid concentration among the pretreatments. In the enzymatic hydrolysis, only a solid-to- liquid ratio showed a significant effect on glucose and xylose concentrations. The ethanol yields obtained by the simultaneous hydrolysis and fermentation process are higher than those obtained when the hydrolysis and fermentation were conducted in separate steps. The highest ethanol yields were obtained with solids loading of 200 g L-1, and 25 FPU g-1 in the prehydrolysis step.

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Carstensen, Daniel [Verfasser]. « Environmentally induced responses of Donax obesulus and Mesodesma donacium (Bivalvia) inhabiting the Humboldt Current System = Umweltinduzierte Resonanz von Donax obesulus und Mesodesma donacium (Bivalvia) aus dem Humboldt Auftriebssystem / Daniel Carstensen ». Bremerhaven : AWI, Alfred-Wegener-Institut für Polar- und Meeresforschung, 2010. http://d-nb.info/1010224115/34.

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Fatunwase, Akintayo. « Simple Pretreatment of Arundo Donax and Enzymatic Conversion of Cellulosic Materials to Glucose ». Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/1.

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Arundodonax (Giant reed Plant) contains cellulose, hemicellulose and lignin and considered as a biomass resources for biofuels. Cellulose is a polymer of several d-glucose linked units coupled with beta-1, 4 glycosidic bonds. The lignin must be broken down to obtain cellulose.Brown and white rot fungusbreak down lignin through a fenton mechanism using hydroxyl radicals. Current work explores degradation of cellulose byisolating microbial communities followed by inoculating 1% carboxymethyl cellulose (CMC) or arundodonax in nutrient media. The microbes demonstrate long-term viability using CMS or arundodonax the sole carbon source.Pretreatment with microbes result in enhanced enzymatic hydrolysis at 50 °C using commercial cellulase over time. The simple dinitrosalicylic acid assay method quantifies glucose, the main product of enzymatic hydrolysis.

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Macias, Raymond A. « Ovipositional cues for a galling wasp, Tetramesa romana, on giant reed (Arundo donax) ». Thesis, California State University, Long Beach, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10254696.

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Arundo donax is a rhizomatous perennial grass that invades riparian habitats and replaces native riparian vegetation. The galling wasp, Tetramesa romana (Hymenoptera: Eurytomidae), was selected for evaluation as a biocontrol agent of A. donax in 2009. However, knowledge is scarce on which factors influence host selection and oviposition in T. romana. Through my observations I documented distinct behavioral steps preceding emergence leading to oviposition in T. romana, and elicited an investigatory response in T. romana from plant volatiles extracted from A. donax. My results indicated that T. romana does use a chemical cue as a factor in host selection, but it is likely not the result of a species-specific constituent. Evidence from my study revealed that T. romana may use a physical cue in selecting a host as well. T. romana preferred round glass rods over flat glass slides, indicating that shape is an important factor in host acceptance.

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Poli, Michele <1987&gt. « Genomic Resources Development and Functional Characterization of Arundo Donax L. under Stress Conditions ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amsdottorato.unibo.it/8091/1/Poli_Michele_tesi.pdf.

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Global warming is becoming a major threat for human and wildlife on Earth and scientists agree in considering anthropogenic greenhouse gasses emission as the main factor contributing to atmosphere and sea temperature increase. Arundo donax L. is the most promising species for second generation biofuel production in Mediterranean areas but up to now little was known about its genetics. In this study, we first explored the whole transcriptome of young shoot of Arundo donax under simulated drought stress through NGS technology. This allowed us to understand the general molecular mechanisms of early plant responses to osmotic stimulus. Through comparative analyses with major Poaceae species, we identified a set of 53 orthologs that can be considered as a core of evolutionary conserved genes important to mediate water stress responses in the family. Leveraging on the availability of this transcriptome, we developed a set of of reliable reference genes with high stability across different stress and/or tissues, to enable further functional studies in this species. We selected a candidate, named AdDWD1, that have the potential to play an important role in stress response by targeted protein degradation. Our results indicate that AdDWD1 is upregulated under osmotic and salt response in A. donax and its overexpression in Arabidopsis brought to a significant decrease in germination under salt and a growth retardation in ABA-containing media. Overexpression of AdDWD1 caused downregulation of DREB2A and SOS3, while it did not affect other stress-related genes, pinpointing a possible pathway-specific regulatory role of the gene. Taken together, these results suggest a strong relation of AdDWD1 with salt and osmotic stress response and an important role in the signalling pathway during early stress stages.

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Corno, L. « ARUNDO DONAX L. (GIANT CANE) AS A FEEDSTOCK FOR BIOENERGY AND GREEN CHEMISTRY ». Doctoral thesis, Università degli Studi di Milano, 2016. http://hdl.handle.net/2434/347217.

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Arundo donax L. or giant cane is a second-generation energy crop that could be used as a feedstock for bioenergy, i.e. biogas, bioethanol, combustion, and in green chemistry as raw material for several industrial sectors. The genetic characterization of A. donax plants revealed that, because of its asexual reproduction, low genetic variability could be detected between plants; the studies on the inflorescences also confirmed the agamic reproduction of the plant. Nevertheless, it could be speculated that some genetic characteristics could be hereditable and a selection of clones could be carried out. The clonal selection showed to be a crucial factor also for the choice of the propagation techniques and their final costs. A. donax biomass conservation by ensilage was possible without using inoculum. The preservation of giant cane could be performed by the two most used silage techniques, trench and silo-bag; the silo-bag technique was more efficient in preserving the biogas potential than trench one. The potential biogas production of A. donax silage in comparison to corn silage was tested by simulation of real-scale anaerobic digestion plant with lab-scale trials. The A. donax biogas production was lower than the one obtained with corn due to the chemical characteristics of biomass and the absence of starch but, thanks to the higher biomass yields, achievable biomethane and electric energy referred to the cultivated surface area were much higher than corn and other traditional energy crops.

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Herrmann, Marko [Verfasser]. « Population dynamics of the surf clams Donax hanleyanus and Mesodesma mactroides from open-Atlantic beaches off Argentina = Populationsdynamik der Brandungsmuscheln Donax hanleyanus und Mesodesma mactroides an offenen Atlantikstränden Argentiniens / Marko Herrmann ». Bremerhaven : AWI, Alfred-Wegener-Institut für Polar- und Meeresforschung, 2009. http://d-nb.info/1010138901/34.

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Lino, Villanueva Gladys Liliana. « Arundo donax L. como gramínea perenne para la producción de biomasa en ambiente Mediterráneo ». Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/398126.

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En los últimos años, es evidente la preocupación mundial sobre las emisiones de gases del efecto invernadero, especialmente CO2. Una de las principales acciones contaminantes es la quema de combustibles fósiles. Paradójicamente la economía mundial depende (directa e indirectamente) en gran medida de la energía derivada de estos combustibles, principalmente petróleo, carbón y gas natural (en medida progresiva). Los combustibles fósiles son finitos, aunque aún tenemos un margen de algunos años para agotarlos. Según los expertos, estamos entrando a una nueva era, que deja de lado los combustibles fósiles y en cambio, usa otras fuentes de energía alternativa, como por ejemplo: la biomasa para la producción de biocombustibles (segunda generación), la energía proveniente del sol y la energía obtenida con la fuerza del aire. Estas fuentes deben usarse en conjunto, no son excluyentes. Una de las decisiones más importantes de la reunión de la COP 21 en París, fue el acuerdo de la disminución progresiva de combustibles fósiles, dado que contaminan altamente el ambiente al liberar grandes cantidades de CO2. Los países industrializados, ya cuentan con algunas investigaciones de años atrás para emplear estas fuentes alternativas. En Europa y EEUU, en cuatro años, se debe incrementar el uso los biocombustibles 10 al 20 %. Por tanto, hacer uso de biomasa para la producción de biocombustibles es de principal interés. En el presente estudio, se trabajó con Arundo donax L., como cultivo energético para evaluar su rendimiento bajo estrés hídrico, a nivel fisiológico, bioquímico y molecular. Los resultados nos indican que A. donax tuvo un buen rendimiento a nivel de producción de biomasa, los parámetros fisiológicos no se ven excesivamente afectados, además que tienen un buena eficiencia en el uso del agua. Los resultados moleculares no proporcionaron mucha información en cuanto a genes de tolerancia a la sequía, sin embargo son resultados valiosos para las futuras investigaciones. Por tanto se puede recomendar a A. donax como un buen candidato a cultivo energético en el ambiente Mediterráneo.
In recent years, global concern about emissions of greenhouse gases, especially CO2, is evident. One of the main pollutants actions is the burning of fossil fuels. Paradoxically, the world economy depends (directly and indirectly) largely on the energy derived from these fuels, mainly oil, coal and natural gas (in progressive measure). Fossil fuels are finite, although we still have a margin of a few years to exhaust them. According to the experts, we are entering to a new era, leaving aside the fossil fuels and instead, uses other alternative energy sources, such as: biomass for the production of biofuels (second generation), energy from the sun and the energy obtained with the air force. These sources must be used together, they are not mutually exclusive. One of the most important decisions of the COP 21 meeting in Paris was the agreement of the progressive decrease in fossil fuels; because of highly pollute the environment by releasing large amounts of CO2. Industrialized countries have already some research done years ago to use these alternative sources. In Europe and the USA, in four years, the use of biofuels should be increased from 10 to 20%. Therefore, make use of biomass for the production of biofuels is a main interest. In the present study, we worked with Arundo donax L., as an energy crop to evaluate their performance under drought stress, physiological, biochemical and molecular level. The results indicate that A. donax is a good performance at the level of biomass production; the physiological parameters are not unduly affected; besides they have a good water use efficiency. The molecular results did not provide much information about genes of drought tolerance; however, results are valuable for future research. Therefore, A. donax can be recommended as a good candidate for energy crop in the Mediterranean environment.

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Guthrie, Gené. « Impacts of the invasive reed Arundo donax on biodiversity at the community-ecosystem level ». Thesis, University of the Western Cape, 2007. http://hdl.handle.net/11394/2313.

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Magister Scientiae - MSc (Biodiversity and Conservation Biology)
Arundo donax is an invasive species that mostly impacts on sensitive riparian ecosystems. Arundo is also invasive in South Africa, though less is known about its ecology, biology, and impacts. Since California and the Western Cape of South AFrica have similar Mediterranean-type climates, we could assume that the impacts of Arundo on ecosystems in California are likely to be similar in the Western Cape, and that control methods used could be extrapolated for use in South Africa. This thesis attempted to determine what impact Arundo has on biodiversity at the community-ecosystem level.
South Africa

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Xu, Jia. « Characterization of Isoprene Synthase from Arundo donax L. in Relation to Abiotic Stress Tolerance ». Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3421964.

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Isoprene (2-methyl-1,3-butadiene, C5H8) is a five carbon volatile hydrocarbon compound, which is synthesized through methylerythritol phosphate (MEP) pathway in the chloroplasts of many plant species. Isoprene has been suggested to enhance plants tolerance to stressful conditions because its emission could be stimulated when leaves are subjected to or recovering from environmental stresses. Physiological function(s) of isoprene emission has been studied for a long time, and previous studies well documented that isoprene emission can enhance plant thermotolerance and oxidative stress resistance; however, whether isoprene emission may increase plant tolerance to drought stress is less studied, and the molecular mechanisms of isoprene emitting plants in response to drought-related stress have never been investigated before. In this study, we characterized the physiological function of the first IspS gene (AdoIspS) from a monocot species, Arundo donax L., in response to different abiotic stresses. First of all, Phenotypic differences under normal growth condition between AdoIspS transgenic and Col-0 wild type plants were observed as follows: earlier flowering time, tendency to higher leaf biomass even though no significant difference, and a higher seed production derived from higher numbers of branching in AdoIspS transgenic plants. The results suggested that isoprene emission may provide a selective advantage to plants by enhancing plant growth rate. In order to investigate the protective function of isoprene emission in response to abiotic stresses, first, the enhanced thermotolerance was tested by analyzing the survival ability between AdoIspS transgenic plants and Col-0. The results indicate that after recovering from the heat shock, AdoIspS transgenic plants exhibited a higher survival rate, chlorophyll content and fresh weight at different developmental stages, which revealed that the transformation of AdoIspS gene isolated from a monocot species can provide similar thermotolerance to isoprene non-emitter as IspSs from dicots. Second, we investigated AdoIspS transgenic plants sensitivity to exogenous abscisic acid (ABA). AdoIspS transgenic plants showed a decreased sensitivity to exogenous ABA application at both germination and seedling stages. qPCR results indicate that under the treatment of ABA on root part, the regulation of ABA-induced genes and ABA biosynthesis genes in root is not affected by the presence of AdoIspS; however, in AdoIspS transgenic leaves, ABA-response mark genes are up-regulated and ABA biosynthesis genes are down-regulated, which supports the idea that isoprene emission may reduce ABA biosynthesis and accumulation in leaves. Therefore, the growth inhibition from exogenous ABA treatment decreased in AdoIspS transgenic plants. To elucidate whether and how the dehydration tolerance was altered or not in later developmental stage of AdoIspS transgenic plants, AdoIspS transgenic Arabidopsis lines were further applied in dehydration stress studies. The results of water loss test and stomatal aperture assay consistently demonstrated that isoprene-emitting plants may have a reduced requirement for ABA to tolerant dehydration stress. Additionally, the survival rate, lipid peroxidation test and dehydration-related gene expression were measured to analyze AdoIspS transgenic plant tolerance to dehydration stress at the whole-plant level, and the results indicate that the better dehydration tolerance displayed in AdoIspS transgenic lines maybe due to the reduced ROS accumulation in isoprene-emitting leaves. These findings suggested that AdoIspS gene plays an important role in plant's tolerance to abiotic stress conditions. Understanding the regulatory mechanisms of AdoIspS gene in response to abiotic stresses could help us find out why isoprene-emitting plants cope better with transient stress events in nature.
Isoprene (2-methyl-1,3-butadiene, C5H8) è un idrocarburo volatile con cinque atomi di carbonio, sintetizzato dalla via metabolica del MEP (metileritritolo fosfato) nei cloroplasti di varie specie di piante. È stato suggerito che l’isoprene possa aumentare la tolleranza delle piante alle condizioni di stress, perché la sua emissione potrebbe essere stimolata quando le foglie sono sottoposte a stress ambientali o ricuperano da essi. Le funzioni fisiologiche dell’emissione di isoprene sono state studiate per lungo tempo. Le ricerche precedenti hanno ben documentano che l’emissione di isoprene può aumentare la tolleranza termica o la resistenza allo stress ossidativo delle piante, ma è meno chiaro se l’emissione di isoprene può aumentare la tolleranza allo stress idrico, e i meccanismi molecolari delle piante che emettono isoprene in relazione alla siccità non sono mai stati investigati prima. Nel presente lavoro, abbiamo caratterizzato la funzione fisiologica del primo gene IspS (AdoIspS) di una specie di monocotiledone, Arundo donax L., in relazione a differenti stress abiotici, tramite overespressione in Arabidopsis thaliana. Le piante transgeniche hanno mostrato una maggiore produzione di semi rispetto a quelle non trasformate. Dopo aver confrontato il tempo di fioritura, la biomassa fogliare e la morfologia delle piante tra tipo selvatico (WT) Col-0 e linee IspS, i risultati suggeriscono che l’emissione di isoprene potrebbe fornire un vantaggio selettivo alle piante attraverso l’aumento del tasso di crescita delle piante. Per investigare la funzione protettiva dell’emissione di isoprene in relazione a stress abiotici, in primo luogo, è stata esaminata la tolleranza termica tramite l’analisi comparativa dell’abilità di sopravvivenza tra piante IspS e Col-0. I risultati indicano che, dopo aver recuperato dallo shock termico, le piante IspS hanno mostrato un più elevato tasso di sopravvivenza, contenuto di clorofilla e peso fresco in diverse fasi di sviluppo. Questo ha rivelato che la trasformazione del gene IspS, isolato da una specie di monocotiledoni, può conferire tolleranza termica a una specie che non emette isoprene, analogamente alle IspSs da dicotiledoni. In secondo luogo, abbiamo investigato la sensibilità delle piante IspS alla somministrazione di acido abscissico esogeno (ABA), in quanto l’ABA è una molecola-chiave nella protezione delle piante sotto stress idrico, ed è prodotto a valle della via biosintetica del MEP. Le piante IspS hanno mostrato una ridotta sensibilità all’applicazione esogena di ABA sia in fase di germinazione sia in fase di semina. I risultati di qPCR indicano che, con il trattamento di ABA alla parte ipogea della pianta, la regolazione dei geni indotti da ABA e dei geni di biosintesi dell’ABA in radice non è influenzata dalla presenza di IspS. Tuttavia, nelle foglie transgeniche per IspS, l’espressione dei geni reattivi all’ABA viene indotta, mentre quella dei geni di biosintesi dell’ABA è repressa. Questi risultati supportano l’idea che l’emissione di isoprene potrebbe essere implicata nella biosintesi e accumulo fogliare di ABA. Pertanto, la presenza di IspS potrebbe influire/alterare ulteriormente il meccanismo della tolleranza alla siccità delle piante che non emettono isoprene, mediando i meccanismi dipendenti dall'ABA di protezione contro lo stress idrico. Per verificare se ed in caso come la trasformazione di IspS altera la tolleranza alla disidratazione delle piante, nell’ultima parte del lavoro, le linee di Arabidopsis transgeniche per IspS sono state utilizzate nello studio di stress conseguente alla disidratazione. I risultati del test di perdita di acqua e l’analisi dell’apertura stomatica confermano che, le piante che emettono isoprene potrebbero richiedere una quantità minore di ABA per tollerare lo stress causato da disidratazione. Inoltre, il tasso di sopravvivenza, come anche il test di perossidazione dei lipidi e l’espressione dei geni relativi alla disidratazione sono stati misurati per analizzare l’aumentata tolleranza alla disidratazione delle linee IspS a livello di intera pianta. I risultati indicano che la migliore tolleranza alla disidratazione mostrata in piante transgeniche per IspS forse risulta dal ridotto accumulo di specie reattive dell’ossigeno (ROS) in foglie che mettono isoprene. Queste scoperte suggeriscono che il gene IspS ha un ruolo importante nella tolleranza delle piante a condizioni di stress abiotico. Comprendere i meccanismi regolatori del gene IspS in risposta allo stress abiotico potrebbe aiutarci a scoprire perché le piante che emettono isoprene superano meglio gli eventi di stress transitorio in natura.

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Smith, Rachel. « Agronomy of the energy crops Miscanthus x giganteus, Arundo donax and Phalaris arundinacea in Wales ». Thesis, Cardiff University, 2008. http://orca.cf.ac.uk/54496/.

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For this study, the energy crops Miscanthus x giganteus, Arundo donax and Phalaris arundinacea were planted at sites across Wales. Non-destructive methods of estimating crop yields were developed the most significant relationship for Miscanthus was between mean shoot height and mean shoot dry weight, whereas for Arundo it was between mean shoot volume and mean shoot dry weight although these estimates were over-estimates of actual crop yield when scaled up to field size. Yield estimates were obtained from destructive sampling for Phalaris and these were shown to be under estimates of whole crop yield. Crop growth data were compared in relation to soil type, soil chemistry and climatic conditions. Soil clay content and soil preparation were identified as of utmost importance to Miscanthus and Arundo success, but had no effect on Phalaris crops. Both Arundo and Miscanthus showed sensitivity to air temperatures during the growing season. Delaying harvest of both crops produced material with decreased moisture and mineral content, although results were not significant in all cases. The nitrogen, phosphorus and potassium content of leaves were higher than that in the cane, and harvest following leaf abscission was recommended. Arundo did not senesce completely during the winter period, and produced harvested material with higher mineral content than Miscanthus. Both crops required further drying to meet moisture content requirements for combustion crops. Phalaris was the only crop to meet moisture content and mineral content threshold levels, although the results were not consistent across sites. Leaf chlorophyll content was significantly correlated to above ground plant mineral content. Organic and inorganic fertilisers were applied to the three crops, and produced no response in Phalaris. Both Miscanthus and Arundo increased growth in response to high phosphorus levels, and generally in response to high fertiliser applications. At recommended application rates cattle manure showed most effect.

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Bandeira, Filipa de Sousa. « Otimização da produção de xilitol por estirpes de Debaryomyces hansenii em hidrolisado de Arundo donax ». Master's thesis, ISA/UTL, 2012. http://hdl.handle.net/10400.5/5302.

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Mestrado em Engenharia Alimentar - Processamento de Alimentos - Instituto Superior de Agronomia
Arundo donax L. is a Mediterranean energy crop with a high potential for the production of bioenergy and added-value products. Nevertheless, its exploration within a biorefinery framework still requires further developments. This work aims to contribute for the development of a strategy to upgrade its hemicellulose fraction, by means of xylitol bioproduction. The raw material was milled and the influence of particle size on acid hydrolysis was studied. The composition of the hydrolysates and residual solids obtained did not differ significantly for the different fractions tested (< 2 mm). Three Debaryomyces hansenii strains were compared in chemically defined medium (CDM), and their tolerance and acclimatization were studied using non-detoxified hydrolysate-based medium (HM). Strain CCMI 941 presented the highest xylose consumption rate (0.26 g·L-1·h-1) in CDM and the best tolerance to the HM. For this reason, this strain was selected for the optimization of the xylitol bioprocess. The best results for xylitol yield and productivity in overall process (0.77 g·g-1 and 0.09 g·L-1·h-1, respectively) were obtained under semi-aerobic conditions, using a twofold concentrated, not supplemented, non-detoxified hydrolyzate and an inoculum with a single step of acclimatization under full aerobic conditions. This yield is one of the highest reported in literature for this strain

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Maxfield, Jason Charles. « Agricultural Management Decisions Impact Isoprene Emission and Physiology of Arundo donax, an Emerging Bioenergy Crop ». PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1642.

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Arundo donax (Giant Reed) is quickly being developed as a rapidly-growing, robust, and highly productive bioenergy crop, with large scale cultivation of this species planned for the Columbia River basin of the Pacific Northwest (USA). Despite its potential as a next generation biomass crop, relatively few studies have examined the physiological performance of A. donax under agricultural conditions. Unlike traditional crops, A. donax is known to be a high-emitter of the volatile compound isoprene, which may significantly impact regional air quality, but it has not been widely cultivated in North America and little is known about how this species will perform in the Pacific Northwest. Over two field seasons, we measured isoprene fluxes from A. donax plants in both greenhouse conditions and in an agricultural field setting under a variety of conditions and fertilizer treatments. We also measured several other attributes of A. donax productivity and leaf physiology including chlorophyll content, photosynthesis rate, stomatal conductance, specific leaf mass, water use efficiency and gas exchange. We found that A. donax physiologically performs well under cultivation in the Columbia River basin, but that it also emits isoprene at significantly higher rates than previous reports indicate. We also found that both isoprene emission and leaf physiology were highly affected by agricultural management decisions, including nitrogen and irrigation management. Our findings indicate that crop management strategies can be developed that simultaneously seek to minimize isoprene emission while maximizing biomass production in this newly emerging bioenergy crop.

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Coppolino, Francesco Saverio. « Prove di caratterizzazione meccanica della canna comune (Arundo Donax) in prospettiva di un uso strutturale sostenibile ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20173/.

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L’obiettivo di questa tesi è porre le basi dell’utilizzo dell’Arundo Donax in campo strutturale estendendo la conoscenza del suo comportamento meccanico attraverso una completa caratterizzazione meccanica. La canna comune vanta delle caratteristiche meccaniche molto simili a quelle di diverse specie di Bambù, materiale ampiamente utilizzato nei paesi dell’Asia orientale e dell’America Latina, dove è inserito nelle normative che ne regolarizzano l’utilizzo ai fini strutturali. La principale norma di riferimento per il bambù è la ISO 22157 (2019), che descrive le procedure di prova da seguire in laboratorio per una corretta caratterizzazione meccanica del materiale. La sopracitata norma è stata di riferimento nella definizione delle diverse prove eseguite sull’Arundo Donax, ma le esigue dimensioni dei campioni, se paragonate a quelle del bambù, hanno portato al progetto di nuove metodologie di prova, studiate “su misura” per ottenere una corretta caratterizzazione del materiale. La modalità di prova a compressione assiale non presenta particolari differenze da quanto indicato nella ISO 22157; lo studio si è quindi incentrato sulle possibili soluzioni da adottare nell’esecuzione dei test a trazione, a taglio e a compressione trasversale, prove che anche per il bambù presentano una significativa dispersione dei risultati e sono in continuo aggiornamento dal punto di vista normativo. Le ridotte dimensioni della sezione comportano diverse difficoltà nel monitoraggio della prova con tecniche di misurazione standard. Si utilizza la DIC, una tecnica di monitoraggio contactless in grado di costruire dei campi vettoriali di deformazione della superfice del campione; tale tecnica di acquisizione permette di cogliere al meglio il comportamento di un materiale fortemente anisotropo come l’Arundo Donax, le cui proprietà meccaniche sono dipendenti dalla direzione di applicazione del carico e le cui caratteristiche di rigidezza variano sullo spessore e lungo lo sviluppo del culmo.

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Lawton, Clare Elizabeth. « A study of variation in the quality of oboe reeds made from Arundo donax L. (Gramieae) ». Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297428.

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Simões, Kenya Carla Cardoso. « Ocorrência e caracterização da espécie invasora Arundo donax L. (CANA-DO-REINO) no Distrito Federal, Brasil ». reponame:Repositório Institucional da UnB, 2013. http://repositorio.unb.br/handle/10482/13791.

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Dissertação (mestrado)—Universidade de Brasília, Departamento de Ecologia, Programa de Pós-Graduação em Ecologia, 2013.
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A degradação do solo e dos ecossistemas nativos e a dispersão de espécies exóticas são as maiores e mais amplas ameaças à biodiversidade do Cerrado. Arundo donax L. (CANA DO REINO) é uma espécie invasora vigorosa que se estabeleceu e espalhou em habitats ripários com clima quente. Uma vez estabilizada, essa espécie se espalha rapidamente, substituindo a vegetação nativa, causando vários impactos no ecossistema. O estudo aqui apresentado tem por objetivo determinar a ocorrência e caracterizar a espécie invasora Arundo donax L. (CANA-DO-REINO) no Distrito Federal, Brasil. Através do mapeamento das populações, observou-se que a maior concentração da espécie está localizada na região central do Distrito Federal e que a presença dessa espécie está relacionada a áreas antropizadas, tais como: rodovias, aterros, depósitos de entulhos (bota-fora) e locais em obras. Após a análise de sementes coletadas no Distrito Federal, não foi encontrada nenhuma espigueta cheia, o que corrobora os trabalhos realizados nos Estados Unidos. E não foi encontrada, com a utilização do marcador molecular do üpo RAPD. uma variabilidade genética entre os indivíduos coletados. Arumdo donax apresentou, no Distrito Federal, uma média de crescimento de 0,01(m.dia-'1), ± 0.01(m.dia'!). A partir de uma análise de regressão observou-se um aumento no peso seco total do indivíduo com o aumento da altura do mesmo, porém esse aumento tende a não ser linear (R2 = 0.8784). Com relação a produção de biomassa. essa variou nos pontos estudados de 0,75kg/m2 a 4.47kg/m2. O estudo ecológico aqui apresentado é pioneiro, pois a maioria dos estudos realizados para essa espécie é dos Estados Unidos e Europa, sendo no Brasil tais estudos inexistentes. ______________________________________________________________________________________ ABSTRACT
Degradation of the soil and of native ecosystems and dispersal of exotic specie are the greatest threats to the biodiversity in the Cerrado. Arundo donax L. is a vigorous invasive species that has established and spread in riparian habitats in warm climates. Once stabilized, this species spreads rapidly, replacing native vegetation, causing various impacts on the ecosystem. The objectives of this study were to determime the occurrence and characterize the invasive species Arundo donax L. (Giant reed) in the Federal District, Brazil. Through mapping its occurrence, we found higher concentrations of the species is in the central region of the Federal District and that the presence of this species was related to disturbed areas, such as highways, landfills, and deposits of construction debris. No viable seeds were found in analysis of panicles collected in several locations in the Federal District, a result similar to studies done m the United States. An analysis of genetic variability using RADP molecular markers did not find any variability in the samples analyzed. In the Federal District Arundo donax presented an average growth of 0.0l (mdia-1) and a standard deviation of 0.0(mdia-1). A regression analysis showed an increase in total dry weight of the individual with increase in height (R2=0.8784). but this mcrease was not linear. In regard to biomass production, this pomts studied ranged from 0.75 kg/m2 to 4.47 kg/m2. The study presented here is pioneer, since most of the studies on this species are from the United States and Europe.

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Zanetti, Gilberto Dolejal. « Lectina dos rizomas de Arundo Donax L. : purificação,caracterização, propriedades,imuno-histoquímica e separação das isoformas ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/10311.

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Algumas características como a falta de cristais de oxalato de cálcio, de estruturas secretoras e de tricomas, e a riqueza de fibras constituíndo estratos localizados imediatamente abaixo da epiderme e limitando o parênquima cortical, e formando bainhas vasculares, subsidia a autenticidade dos rizomas de Arundo donax. Além disto, os rizomas contem amido, cumarinas, alcalóides, flavonóides e saponinas não hemolíticas. Uma lectina (ADL) especifica para GlcNAc e seus derivados oligossacarídeos foi isolada e purificada dos rizomas de Arundo donax L. (Poaceae) por cromatografia de afinidade em matriz de estroma de coelhopoliacrilamida, resultando em uma purificação de 12,15 vezes, rendimento de 6,58% e recuperação de 80 % da atividade hemaglutinante. A lectina purificada é heterotrimérica com massa molecular aproximada de 32.900 estimada por gel de filtração e de 33.000 obtida por SDS-PAGE, em condições não desnaturantes e não redutoras. A lectina purificada possui elevado conteúdo de Glu/Gln, Asp/Asn, Gly e Cys, mas não é glicosilada. ADL é relativamente estável ao calor e ao pH, e resistente à digestão por enzimas proteolíticas. Ela aglutina eritrócitos nativos de coelho, porco e em menor intensidade de rato e humanos A, B, AB e sua atividade hemaglutinante independe de cátions divalentes, mas é diminuída por agentes desnaturantes e redutores. A lectina de Arundo donax L. tem efeito citotóxico para células transformadas da linhagem HT-29, efeito inseticida para Dysdercus peruvianus e nematicida para Meloidogyne incognita. A ADL causou decréscimo na germinabilidade e retardo na germinabilidade dos diásporos de Lactuca sativa L. e também apresentou significativo efeito mitogênico e quimiotáxico. A ADL produziu sinais de toxicidade por via intraperitoneal em camundongos na dose de 300 mg/Kg e com a dose de 800 mg/Kg, 100 % dos camundongos foram a óbito, após 30 horas de sua administração. Sete isoformas da ADL foram separadas por PAGE preparativa. Das seis estudadas todas são heterotriméricas com massas moleculares relativas de suas cadeias polipeptídicas de aproximadamente 8,5, 18,9 e 13,1 kDa, totalizando 40,6 kDa. As isoformas demostraram ser estáveis face a vários fatores químicos e físico-químicos como a ADL, mas apresentaram desiguais intensidades na aglutinação de eritrócitos e inibição por carboidratos. A isoforma ADL-III é rica em resíduos de Glu/Gln, Gly, Asp/Asn e ainda Cys e as cadeias a e b possuem resíduos de triptofano na porção N-terminal. A ADL-III apresentou atividade mitogênica significativa. A ADL foi capaz de ligar-se in vitro a células transformadas das linhagens T-47D, HT-29 e T-24. Por técnicas imunohistoquímicas, a ADL foi detectada na parede celular das fibras e em algumas poucas células do parênquima cortical do rizoma.
Some characteristics like absence of calcium oxalate crystals, secretory structures and trychomes and the richness of fibers that form strata localized immediately under the epiderms and limiting the cortical parenchyma or forming bundle sheaths, subsidize the authenticity of these rhizomes. Besides the rhizomes contain amide, coumarins, alkaloids, flavonoids and nonhemolytic saponins. A lectin (ADL) specific to GlcNac and its oligosaccharides was isolated and purified from Arundo donax L. (Poaceae) rhizomes by affinity chromatography on rabbit stroma-polyacrilamide column. The lectin was purified 12.15 times, the yield of proteins was 6.58 % and the recovery of the hemagglutinating activity was 80 %. The purified lectin is heterotrimeric and has a molecular mass of 32,900 approximately estimated by gel filtration and of 33,000 by SDS-PAGE in non denaturating and non reducing conditions. The purified lectin is rich in Glu/Gln, Asp/Asn, Gly and Cys, but it is not glycosilated. ADL is relatively heat- and pHstable and it is resistent to disgestion by proteolytic enzymes. It agglutinates native rabbit, pig erythrocytes and with lower intensity rat and human A, B and AB erythrocytes, and its hemagglutinating activity is independent of divalent cations, but it is decreased by denaturating and reducing agents. Arundo donax L. lectin displays cytotoxic effect on Dysdercus peruvianus and nematicide activity againt Meloidogyne incognita. ADL decreases the germinability and delays the mean time for germinability of Lactuca sativa L. diasphores and also shows significant mitogenic and chemotactic effect. The lectin induce toxicity signals in mice by intraperitoneal injection with the dose of 300 mg/kg and 800 mg/kg caused 100 % death of the animals, 30 h after its administration. Seven isoforms of ADL were separated by preparative PAGE. The six isoforms studied are heterotrimeric, with polypeptide chains of molecular mass of 8.5, 13.1 and 18.9 kDa determined by mass spectroscophy and with 40.6 kDa of lectin molecular mass. The isoforms showed stability when subjected to the action of distinct chemical and physico-chemical factors as ADL showed. However, they exibited unequal intensity of erythrocyte agglutination and carbohydrate inhibition. ADL-III is rich in Glu/Gln, Gly and Asp/Asn and Cys residues, and its Nterminal a and b chains contain tryptophan residues. ADL-III showed significant mitogenic activity. ADL was able to bind to transformed cells from T-47D, HT-29 and T-24 lines in vitro. Immunohistochemical techniques allowed to localize ADL in the fiber cell walls and in some few cortical parenchyma cells of the rhizome.

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Howe, Catherine E. « A REVIEW OF THE REMOVAL OF ARUNDO DONAX FROM A RIPARIAN AREA WITHIN SAN TIMOTEO CANYON ». CSUSB ScholarWorks, 2014. https://scholarworks.lib.csusb.edu/etd/106.

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A site within San Timoteo Canyon was revisited, 13-14 years after treatment, to look at long-term effects of Arundo donax removal. The data obtained were used to determine whether A. donax had re-invaded, other non-native species had established the area, or if native species were able to grow in place of the removed A. donax. The previous removals included a combination of grinding large patches of A. donax and then foliar spraying, foliar spraying of uncut plants, and direct spraying of hand cut stems, depending upon the location and size of the plant. The effects of the A. donax removals within San Timoteo Canyon were analyzed in relation to new percent cover of the plant species, other more recent removals, and areas that did no experience removal procedures. The project included the use of data provided by the Inland Empire Resource Conservation District (IERCD) as well as the collection of data from randomized plots to generate plant species percent cover. Plant percent cover data analyzed for this paper had been collected from eight 15 by 15 foot randomly selected plots within an overall project site of 42.3 acres. Additional sites were used to investigate what can happen if A. donax is not removed from an area into which it has been introduced., the short-term effects of A. donax removal methods, and the role the ever-changing characteristics of riparian areas can play in their own restoration. These additional sites included aerial photographs supplied by IERCD of an ecologically similar area, a plot with a more recent A. donax removal date, as well as photographs and data of a site subject to natural recovery. Based on these comparisons it is concluded that the treatment methods used led to a lessened presence of A. donax, and that other invasive species did not grow in its place. Further, as the removal procedures within the project area occurred approximately 13 to 14 years prior, it can be concluded that there is no regrowth of A. donax and that many native species have been able to re-inhabit those areas previously infested by A. donax. The treatment methods used were successful without the need to continually disrupt the habitat and allowed for the habitat to recover naturally once the invasive species had been removed.

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Valli, Fabio <1984&gt. « Physical Mutagenesis in Giant Reed (Arundo Donax L.) and Phenotypic and Genomic Characterization of Mutagenized Clones ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amsdottorato.unibo.it/8196/1/Fabio%20Valli%20tesi%20dottorato.pdf.

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ABSTRACT Giant reed (Arundo donaxL.) is a C3 perennial, warm-season, rhizomatous grass of emerging interest for bioenergy and biomass-derivatives production, and for phytoremediation. We developed and applied a mutagenesis protocol based on γ-irradiation of in-vitro cell cultures from which regenerants were obtained. Based on a radio-sensitivity test, the irradiation dose reducing to 50% the number of regenerants per callus (RD50) was estimated at 35 Gy. A large mutagenic experiment was carried out by irradiating a total of 3,120 calli with approx. 1x, 1.5x and 2x RD50. A total of 1,004 regenerants from irradiated calli were hardened in pots and transplanted to the field. Approx. 10% of field grown clones showed remarkable morphological aberrations including dwarfism, altered tillering, abnormal inflorescence, leaf variegation and others, which were tested for stability over generations. Clone lethality reached 0.4%. Our results show for the first time that physical mutagenesis can efficiently induce new genetic and phenotypic variation of agronomic and prospective industrial value in giant reed. 100 clones of A. donax were chemically analyzed for several key chemical components of plant biomass including lignin, cellulose, hemicelluloses, non-structural carbohydrates, ash, and others. The complete chloroplast genome of A. donax is 139353 bp in length subdivide in two inverted repeat region (IRa and IRb) of 22,227 bp each separated by a small-single-copy-region of of 12,275 bp (SSC) and a large-single-copy-region of 82,124 bp (LSC). The genome includes 112 individual genes including 72 protein coding genes, 30 tRNA, 6 rRNA, 3 open reading frames and one pseudogene. FISH ang GISH analysis were performed on three species A. donax, A. plinii and P. australis in order to define the genetic structure of these species and the phylogenetic relationship existing among them.

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Oliveira, Giordano Bruno da Silva. « Potencial energético da espécie Arundo donax l. (cana-do-reino) de ocorrência natural no Distrito Federal - DF ». reponame:Repositório Institucional da UnB, 2014. http://repositorio.unb.br/handle/10482/16829.

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Dissertação (mestrado)–Universidade de Brasília, Faculdade de Tecnologia, Departamento de Pós-Graduação em Ciências Florestais, Tecnologia e Utilização dos Produtos Florestais, 2014
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No mundo há poucas tecnologias capazes de oferecer características de rendimento energético eficiente. Neste cenário, buscar novas fontes de energia, para complementar o setor energético, se torna bastante importante, pois os combustíveis fósseis possuem um ciclo fechado e estoque limitado. Assim, surgem as culturas energéticas que visam produzir biomassa como fonte produtora de energia sólida ou líquida. No Brasil, estas culturas, se baseiam no uso de eucalipto e capim elefante, porém, há outras fontes alternativas de biomassa eficientes. Entre elas, há a espécie Arundo donax L., com alta capacidade adaptativa para os diversos ambientes, alto índice de produção, alta eficiência energética, baixo custo de produção e exploração. Neste sentido, foi feito um estudo sobre o potencial energético da Arundo donax L., proveniente de ocorrência natural no Distrito Federal - DF, verificando seu potencial como fonte geradora de energia. Os colmos foram coletados no Distrito Federal, totalizando 753 indivíduos em 30 m² de área amostral. Os resultados mostraram altura média de 3,86 m com diâmetro de 2,03 cm, biomassa verde de 12,75 kg/m², com 6,64 kg/m² de massa seca. A variável altura apresentou alta correlação com a massa seca e por isso foi escolhida para dividir os colmos em quatro classes e três posições axiais, para estudo das características energéticas do material. Os resultados mostram que para a posição axial da base e classe de altura quatro (maior altura) dos colmos os teores de carbono fixo e o poder calorífico foram maiores. Mas com a densidade básica ocorre o contrário, ou seja, maiores valores para as posições de topo e a classe um (menor altura). Devido ao comportamento da densidade, as maiores densidades energéticas foram encontradas na posição axial de topo e nas classes de menor altura, um e dois. ______________________________________________________________________________ ABSTRACT
In the world, there are few technologies that can provide characteristics of efficient energy performance. In this scenario, seek for new sources of energy to supplement the energy sector, becomes quite important because fossil fuels have limited stock and a closed cycle. Thus, energy crops aimed at producing biomass as a source of producing solid or liquid energy arise. In Brazil, these cultures, are based on the use of eucalyptus and elephant grass; however, there are other effective alternative sources of biomass. Among them are the Arundo donax L. species with high adaptive capacity to different environments, high production rate, high-energy efficiency, low cost of production and operation. In this respect, a study on the energy potential of Arundo donax L. from naturally occurring in the Distrito Federal, checking its potential as power source was made. The stems were collected in the Distrito Federal, totaling 753 individuals in 30 m² sampling area. The results showed an average height of 3.86 m with a diameter of 2.03 cm, green biomass of 12.75 kg/m², with 6.64 kg/m² of dry mass. The variable height was highly correlated with dry mass and was therefore chosen to split the stems into four classes and three axial positions, to study the material energy characteristics. The results show that the axial position baseand the height fourclass (maximum height) of the stems, the fixed carbon content and calorific value were higher. However, with the basic density occurs the opposite, ie, higher values for the top positions and class one (lower height). Due to the behavior of the density, the higher energy densitieswere found in the axial position of the top and classes of smaller size, one and two.

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Sidella, Sarah. « Adaptability, Biomass Yield, and Phytoremediation of Arundo donax L. on marginal lands : salt, dry and lead-contaminated soils ». Doctoral thesis, Università di Catania, 2014. http://hdl.handle.net/10761/1605.

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Water shortage, especially during spring and summer seasons, is the main limiting factor the crop production (Araus et al, 2002; Passioura, 1977), moreover, in the Mediterranean area, inadequate irrigation practices may also exacerbate the problem of the soil salinity. The pollution of soils due to accumulation of heavy metals is a global problem that may involve the loss of agricultural areas: contaminated land is no longer suited to farming, and may be especially harmful to the entire ecosystem (Alloway, 1995). Plants tolerant to heavy metals, may be used to enhance sites unsuitable for biomass production, restoring the ecosystem services and providing valuable feedstocks to biorefineries, in a phytoremediation process. Among the perennial species for energy purpose, Arundo donax L. could be a suitable species for marginal lands including dry areas, salt and lead contaminated soil in the Mediterranean environment. On the basis of these premises the following research lines were carried out with the aim of assess the possibility of cultivate Arundo donax L. on dry, salt and lead contaminated marginal lands: - Line 1: Giant reed screening to salinity levels - Line 2: Response of Arundo donax L. clones at increasing levels of salinity and at different soil water content - Line 3: Phytoremediation of Arundo donax L. in lead-contaminated soils with different water levels of the soil - Line 4: Phytoremediation of different Arundo donax L. clones in lead-contaminated soils The effect of NaCl concentration in the soil induced by irrigation, influenced the morphology and physiology of the studied clones. The results showed that under conditions of salt and water stress all the physiological parameters were affected and plants growth, aboveground dry biomass yield were reduced. Giant reed was able to grow with irrigation water up to 12 dS m-1. However, if this parameter would be considered to classify a soil as marginal, it is clear that marginal land would be obtained marginal yields. Although the Arundo plants are not hyperaccumulators, high phytoextraction yields can be achieved in contaminated soils, due to a conjugation of phytotolerance and high yields. This allows us to consider that Arundo can be more efficient than certain hyperaccumulator plants but with very low yields. On the other hand, the viable growth of Arundo in contaminated soil and subsequent soil revegetation, ensures the long term stability of the surface, reducing the leachates, the amount of potentially toxic elements released into watercourses and groundwater and the development of a vegetative landscape or ecosystem in harmony with the surrounding environment.

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Undurraga, Montalba Nicole. « Fluctuación poblacional del áfido Melanaphis donacis (Passerini) (Hemiptera : aphididae) y su efecto sobre el rendimiento de Arundo donax (L.) ». Tesis, Universidad de Chile, 2014. http://repositorio.uchile.cl/handle/2250/149050.

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Tesis para optar al Título Profesional de Ingeniero Agrónomo y al Grado de Magíster en Ciencias Agropecuarias, Mención Sanidad Vegetal
El desarrollo de fuentes de energía renovable, particularmente de cultivos energéticos como la caña común, Arundo donax, hace necesario identificar las potenciales plagas asociadas y sus posibles consecuencias en la producción. El áfido Melanaphis donacis (Passerini), es el principal artrópodo que se ha visto asociado a esta especie en parcelas experimentales en la región Metropolitana. Con el objetivo de aportar información básica para un futuro desarrollo de este cultivo y diseñar estrategias de manejo adecuadas y oportunas, se estudió el cambio en abundancia durante un año (2013) de la población de este áfido. Los niveles poblacionales se midieron a través de colectas quincenales de áfidos sobre hojas, desde parcelas sin tratamientos insecticidas y de una población silvestre de A. donax, realizando un recuento directo, calculando la media del número de áfidos por hoja por día de muestreo. El áfido estuvo presente durante todo el año en plantas de A. donax cultivado, siendo especialmente abundante en primavera-verano, con un número promedio máximo de 243 individuos hoja-1, mientras que en las plantas silvestres sólo se llegó a un máximo de 147 áfidos hoja-1. Además, se observaron abundantes enemigos naturales, especialmente coccinélidos y sírfidos, los que podrían estar contribuyendo a mantener las poblaciones de áfidos bajo niveles dañinos.
The development of renewable energy, particularly energy based on crops such as the giant reed, Arundo donax, this make necessary to identify potential associated pests and their possible impact on their production. The aphid Melanaphis donacis (Passerini) is the main arthropod that has been associated with this specie in experimental plots in the Metropolitan region. In order to provide basic information for future development of this crop and design management strategies that are appropriate and suitable, the variation of population of this aphid was studied for one year (2013). Population levels were measured through fortnightly collections of leaves from wild plots of A. donax without insecticide treatments, counting and recording the average per leave and sampling day. The aphid was present throughout year long, being especially abundant in spring and summer, with a maxim average number 243 individuals per leaf, while in wild plants only reached to a maximum of 147 aphids per leaf. Also natural enemies that help to keep aphid populations under damaging levels were observed abundantly, especially ladybirds and hoverflies.

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Stenton-Dozey, Jeanette Mary Edgeworth. « Physiology and energetics of the sandy-beach bivalve Donax serra Röding with special reference to temperature and chlorine tolerance ». Doctoral thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/15894.

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Bibliography: pages 287-318.
This thesis examines the physiology and energetics of D. serra and considers physiological responses to elevated temperature and chlorine levels typical of sea water discharged from a nuclear power station.

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SIDOUMOU, ZEINABOU. « Qualite des eaux du littoral mauritanien : etude des metaux traces chez deux mollusques bivalves venus verrucosa et donax rugosus ». Nice, 1991. http://www.theses.fr/1991NICE4468.

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Le but de ce travail a ete de considerer l'impact de metaux traces essentiels (cu, fe, mn, zn) ou non essentiels (cd) sur deux mollusques bivalves de la cote mauritanienne. Les concentrations en metaux naturellement presents ont ete etudiees chez la praire venus verrucosa et le haricot de mer donax rugosus. Des variations spatiales ont ete observees chez les deux mollusques. Des differences de concentrations en metaux dues aux fluctuations ponderales ont ete trouvees suivant un cycle annuel. L'espece la plus grosse v. Verrucosa a les teneurs les plus faibles en metaux a l'exception du cadmium par rapport a d. Rugosus. Pour v. Verrucosa, les branchies concentrent les metaux par rapport a la praire in toto; pour d. Rugosus, la masse viscerale et les branchies accumulent le plus les metaux. Donax rugosus a ete choisi pour une experimentation en laboratoire de la toxicite et la bioaccumulation du cadmium. A la meme temperature d'experience, d. Rugosus s'est revele plus sensible en ete qu'en hiver, ceci peut etre lie a la condition physiologique des animaux. L'accumulation du cd par d. Rugosus est proportionnelle au temps de contact et a la concentration de ce metal dans le milieu. Elle est inhibee par la presence d'edta ou du zn. Cd est particulierement concentre par les branchies. Les experiences de decontamination montrent que ce metal a ete bien absorbe et non pas seulement absorbe. En conclusion, notre etude montre que les deux mollusques etudies sont de bons modeles pour mettre en evidence une pollution eventuelle du littoral mauritanien

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ROTUNNO, Silvia. « An integrated next generation sequencing approach to define and improve the productive efficiency of the energy crop Arundo donax ». Doctoral thesis, Università degli studi del Molise, 2022. https://hdl.handle.net/11695/114307.

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L’obiettivo 7 dell’Agenda 2030 per lo Sviluppo Sostenibile è assicurare energia sostenibile a prezzi accessibili, promuovendo lo sviluppo tecnologico e l’innovazione. Nel 2019, il report prodotto dalla FOLU (The Food and Land Use Coalition) ha indicato la necessità di “focalizzarsi sulla bioenergia che non incrementa (o lo fa in maniera minima) la pressione sull’utilizzo del suolo”, usando colture energetiche che non competono con la produzione di cibo, con le foreste o con il recupero di terreni degradati. Inoltre, la direttiva EU 2018/2001 incoraggia gli Stati Membri a produrre ed utilizzare energia proveniente da fonti rinnovabili. Arundo donax L è una coltura bioenergetica molto promettente, che risponde ai requisiti di scarsa pressione sul suolo, in quanto capace di crescere su terreni marginali/degradati senza eccessive richieste di cura, ed è una coltura non alimentare. Tuttavia, la recalcitranza della biomassa lignocellulosica alla degradazione in zuccheri fermentabili rappresenta il suo principale limite nell’utilizzo per la produzione di energia. Il principale obiettivo di questa tesi è stato quello di investigare le risposte molecolari di A. donax a stress salino e/o eutrofizzazione, problemi principali dei terreni marginali, per capire se e quanto venga influenzata la produzione di lignina. Per fare ciò, è stata utilizzata una combinazione di approcci di Next Generation Sequencing, quali RNA-sequencing, smallRNA-sequencing and degradome-sequencing. I risultati ottenuti possono essere sintetizzati in tre punti. Primo, dall’analisi dei geni differenzialmente espressi e dall’analisi del contenuto di lignina e dell’attività delle perossidasi, viene suggerita una rimodulazione nella composizione della lignina, che sembra coinvolgere una diversa deposizione dei monomeri da cui è composta. Secondo, è stato creato per la prima volta e un catalogo di microRNA, conservati e nuovi, presenti in arundo. Infine, è stata individuata una lista di possibili target da utilizzare per approcci di miglioramento biotecnologico, sia per la tolleranza agli stress che per la resa in termini di biomassa, tramite la combinazione dei dati di degradome-, smallRNA- e RNA-sequencing. Nel loro insieme, tali risultati possono aiutare a comprendere i meccanismi regolativi trascrizionali e post-trascrizionali in arundo, nonostante la mancanza di un genoma di riferimento. Inoltre, approfondire la conoscenza sulla capacità dell’arundo di fronteggiare lo stress salino e il disequilibrio nutritivo, può essere di notevole aiuto nel promuovere l’utilizzo di tale pianta per progetti di riqualificazione di terreni marginali o abbandonati, aiutando a limitare la pressione sull’utilizzo del suolo e mitigare gli effetti del cambiamento climatico.
The mission of goal 7 of 2030 Agenda for Sustainable Development is ensuring sustainable energy at accessible price, promoting technological development and innovation. The 2019 Global report from The Food and Land Use Coalition (FOLU) claims the need to “focus on bioenergy that do not (or only minimally) increases the pression on land use”, cultivating energy crops that do not compete with food production, forest or degraded land restoration. Moreover, the last directive EU 2018/2001 encourages the Member States towards production and usage of energy from renewable sources. The bioenergy crop Arundo donax L is a promising crop that addresses the requisites of low pressure on soils, being able to grow on marginal/degraded land, needing low input, and being a non-edible crop. However, the recalcitrance of its lignocellulosic biomass to enzymatic degradation into fermentable sugars is the main limiting factor in energy production. The amount of lignocellulosic biomass is linked to the lignin deposition and is reported in the literature to be related to stress responses. Thus, the main aim of this thesis was investigating the molecular responses of A. donax to salt stress and/or eutrophication, which affects marginal land, in order to understand if and how lignin deposition is affected. A combination of different Next Generation Sequencing (NGS) approaches, such as RNA-sequencing, smallRNA-sequencing and degradome-sequencing, were applied. Results obtained could be summarized in three points. First, a remodulation of lignin composition, involving a different lignol monomers deposition, was suggested by differential gene expression and analysis on lignin content and peroxidases activity. Second, a catalogue of microRNAs, both conserved and novel, in arundo from direct NGS was built for the first time. Finally, a list of possible targets for biotechnological improvement for both stress tolerance and biomass yield was generated thanks to the analysis of degradome-sequencing data combined with smallRNAs- and RNA-sequencing data. Taken together, these results could help improve knowledge on transcriptional and post-transcriptional regulation mechanisms in arundo, despite the lack of a reference genome. Furthermore, deepening the knowledge on arundo ability to cope with salt stress and nutrients imbalance could help in using this plant for requalification of marginal and abandoned lands, helping to lighten the pressure on soil usage and mitigating climate change effects.

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PIGNA, GAIA. « DEVELOPING TOOLS FOR ACCELERATING THE DOMESTICATION OF TWO PROMISING BIOFUEL CROPS : ARUNDO DONAX (GIANT REED) AND PANICUM VIRGATUM (SWITCHGRASS) ». Doctoral thesis, Università degli Studi di Milano, 2016. http://hdl.handle.net/2434/460351.

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The need for energy and the unsustainability in the long term of fossil fuels encouraged the quest for more environmental-friendly energy sources. One alternative is exploiting plants to produce biofuels. The screening of many perennial grasses suggested Miscanthus (Miscanthus spp), Arundo (Arundo donax), and reed canary grass (Phalaris arundinacea) in Europe and switchgrass (Panicum virgatum) in both Europe and US as good candidates for bioenergy production. This thesis focuses on two of these plants: Arundo and switchgrass. Both plants already show a good agronomic performance, but they underwent little domestication, so there is room for their genetic improvement. On the contrary to switchgrass, breeding, genetic transformation and in vitro cultivation of Arundo are lagging behind for the sterility and the recalcitrance of this plant. We developed a method for in vitro cultivation of Arundo that is faster and more efficient than the one previously reported in literature. Calli are induced from stem segments on an MS-based medium containing 9 μM 2,4-D and then a suspension culture can be obtained using the same medium supplemented with 4.4 μM BAP, leading to a 5-fold increase in cell mass over 14 days. This medium was the best in terms of growth rate and final cell density among the four tested media. Protocols for protoplast isolation from suspension cultures and electroporation were also established, allowing a transformation Tools for improving biofuel crops 4 efficiency up to 3.3±1.5 %. The use of a novel vector with two distinct fluorescent protein reporters (GFP and RFP) driven, respectively, by the Cauliflower Mosaic Virus 35S and the ubi2 promoter of switchgrass, allowed a direct comparison of the strength of the two promoters in Arundo. The switchgrass ubi2 promoter provided a much higher expression compared with the 35S promoter. Lastly, as a further methodological advancement, we developed a method to cryopreserve mesophyll protoplast of switchgrass. Both vitrification and slow-freezing methods were tested. Slow freezing is more efficient than vitrification with a percent recovery of alive protoplast of 45.8% vs. 5.2%.

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Wong, Cheuk-Kee Edward, et 王卓基. « The ecology of exposed sandy beaches in Hong Kong with particular reference to Donax semigranosus and D. cuneatus (Bivalvia :Donacidae) ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1989. http://hub.hku.hk/bib/B31208952.

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Rüggeberg, Markus [Verfasser], et Thomas [Akademischer Betreuer] Speck. « The mechanical and structural design of tissue interfaces in the Mexican Fanpalm (Washingtonia robusta) and the Giant Reed (Arundo donax) ». Freiburg : Universität, 2009. http://d-nb.info/1241042918/34.

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Ramos, Romero Diego. « Producción de tableros de fibras sin adición de adhesivos a partir de arundo donax L. Y bagazo de Saccharum officinarum L ». Doctoral thesis, Universitat Rovira i Virgili, 2012. http://hdl.handle.net/10803/97205.

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En este trabajo se estudian los parámetros de obtención de tableros sin aporte de adhesivos, a partir de materiales lignocelulósicoscomo son la caña común (Arundodonax L.) y el bagazo de SaccharumofficinarumL. Los tableros propuestos aportan como ventaja el estar libres de emisiones de formaldehído y el no consumir recursos fósiles. Ambas propiedades son importantes en un mercado cada vez más exigente en aspectos medioambientales. En el caso del “ArundodonaxL” se ha partido de cañas silvestres de Tarragona. El bagazo de Saccharumofficinarum utilizado es el subproducto industrial de una destilería de la Isla de la Palma (Canarias). El material crudo ha sido pretratado realizando una “explosión de vapor” en un reactor “batch” a distintas condiciones de severidad. Este material explosionado se ha triturado y prensado en frío de dos formas (en seco y en húmedo). Posteriormente, los tableros prensados en frío y acondicionados a temperatura y HR constantes se han prensado en caliente a diferentes niveles de presión, temperatura y tiempo de prensado. En el proceso de producción a escala de laboratorio de los tableros, se han mejorado algunas de las fases seguidas como el prensado, introduciendo mallas de evacuación de vapor; y se han innovado otros, como la incorporación del prensado en frío y el tratamiento térmico final después de la conformación en caliente. Todo ello para mejorar la homogeneidad y obtener tableros de altas prestaciones mecánicas con estosmateriales. Se ha podido estudiar el efecto de los distintos factores que intervienen en la producción de tableros (Severidad del pretratamiento, temperatura de prensado, presión de prensado y tiempo de prensado), sobre las características físicas y mecánicas de estos tableros(Densidad, MOE, MOR, IB, TS y WA). Con ello se han obtenido las relaciones matemáticas que vinculan a estos factores de producción con las características físicas y mecánicas de los tableros. Puede ser muy importante para la industria el hecho de que los modelos ajustados definidos nos pueden permitir obtener tableros con características prefijadas. También se ha valorado la utilización de material integro explosionado y no lavado y, por tanto, sin ningún lixiviado ni residuo. Los tableros cumplen sobradamente los requerimientos de las norma EN para uso estructural, en todas las características físico-mecánicas estudiadas. Abreviaturas: HR Humedad relativa MOE Módulo de elasticidad en flexión o Módulo de Young MOR Módulo de rotura o Resistencia a la flexión IB Resistencia a la tracción perpendicular a las caras (Internal Bond) TS Hinchamiento WA Absorción de agua
This work studies the parameters for obtaining binderless fiberboards from lignocelullosic materials such as giant reed (Arundodonax L.) and sugar cane bagasse (Saccharumofficinarum L.) The suggested boards havethe advantage of being free from formaldehyde emissions and of not consuming fossil resources. Both properties are important in a market that is increasingly sensitivetowards environmental issues. Wild reeds from Tarragona were used as the base material to make Arundodonax Lfiberboards. The Saccharumoffinarumsugar cane bagasse was anindustrial byproduct obtained from a plantation on the island ofLa Palma in the Canary Islands (DestileríasAldea SL). The raw material was pre-treated by performing a “steam explosion” in a “batch” reactor. The exploded material was ground and cold-pressed in two ways (wet and dry). Subsequently, the cold-pressed boards, which had beenconditioned at a constant temperature and RH, were hot-pressed at different levels of pressure, temperature and press time. Some of the processes for producing boards on a laboratory-scale,such as pressing withsteam evacuation meshes, have been improved. Others processes were specifically developed in the laboratory, including the incorporation of cold-pressing and the final heat treatment after hot-forming. The aim of all this was to achieve high mechanical performance in boards made from these materials. Different factors involved in the production of the boards were studied (severity of pretreatment, pressing temperature, pressing pressure and pressing time) to determine how they affectthe physical and mechanical properties of these boards (density, MOE, MOR, IB, TS and WA). As a result, the mathematical relationships that link these production factors to the physical and mechanical properties of the boards were obtained. It is very significant for the industry that these adjusted models can produce boards with preset characteristics. The use of material that wascompletely exploded and unwashed and, therefore, without residue has also been studied. In terms of all the physical-mechanical characteristics studied,the boards fully comply with the requirements of the EN standards for structural use. Abbreviations RHRelativehumidity MOE Modulus of elasticity MOR Modulus of rupture IB Internal bond TS Thicknessswelling WA Water absorption

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Galimberti, Mariagrazia. « Investigation the use of oxygen and carbon isotopes and sclerochronology on Turbo sarmaticus and Donax serra for palaeoenvironment reconstruction at Pinnacle Point, South Africa ». Doctoral thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/10516.

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Includes bibliographical references (p. 241-272).
This thesis investigates the validity of oxygen isotope analysis for the gastropod Turbo sarmaticus (operculum and shell) and the bivalve Donax serra to reconstruct sea surface temperatures. These are the species most commonly retrieved from archaeological assemblages of the South Coast of South Africa. The material analysed for this thesis includes modern and archaeological shells from Pinnacle Point, Mossel Bay. Evidence of human occupation of coastal caves here dates as far back as 164 kya. Specimens analysed for this study date between 114 and 91 ky. Analysis of edge increments shows that all the archaeological specimens were collected in winter and/or in spring and autumn, pointing to seasonal exploitation; the first documentation of this kind of seasonal scheduling of activities in Middle Stone Age sites in South Africa.

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Magalhães, Luísa Virgínia de Sousa. « Inventory, dynamics and impact of the trematodes parasites in bivalves with high economic importance ». Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0174/document.

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Parmi les agents qui modulent la dynamique des populations, le parasitisme est important mais souvent négligé. Il est urgent non seulement d’inventorier les différentes espèces de parasites, mais aussi de comprendre la sensibilité des hôtes à l’infection (notamment des bivalves) et étudier les interactions entre les parasites et les autres facteurs environnementaux. Par conséquent, cette thèse avait comme objectif principal de caractériser et de quantifier les communautés de trématodes (les plus abondants et répandus des macroparasites de bivalves dans les eaux côtières) qui infectent Cerastoderma edule (coque) et Donax trunculus (telline), deux des bivalves les plus importants au Portugal et en France d’un point de vue écologique et économique.Dans un premier temps, la dynamique des populations de bivalves a été étudiée en tenant compte de la relation entre la température et la période de recrutement et des effets en retour du recrutement sur la biomasse adulte. Pour cela, une base de données a été analysée couvrant 17 ans d’observations mensuelles d’une population de coques dans une réserve nationale (Banc d’Arguin, Arcachon, France). Ces observations à long terme ont montré que la durabilité d’une population de coques dépend du succès du recrutement. Pour les coques, le succès du recrutement a été montré comme étant en partie, mais pas totalement, dépendant de la température. Ainsi, la durée de vie d’une cohorte pourrait être estimée plus tôt, grâce à des indices se produisant en amont du recrutement. Suite à ces résultats, le rôle du parasitisme dans la dynamique des populations de bivalves a été étudié.Premièrement, en raison de leur forte pathogénicité pour les bivalves, une attention particulière a été accordée aux parasites Bucephalus minimus et Bacciger bacciger qui utilisent C. edule et D. trunculus, respectivement, comme premier hôte intermédiaire (où se développe le stade parasitaire sporocyste). [...]Deuxièmement, cette étude s’est concentrée sur l’infection des bivalves par les métacercaires, c’est-à-dire lorsqu’ils servent de second hôte intermédiaire dans le cycle de vie du parasite. […]Enfin, la sensibilité des bivalves à l’infection parasitaire a été évaluée expérimentalement lorsqu’ils sont confrontés à des facteurs liés au changement climatique (salinité, température et pH) et à la contamination (arsenic). Les résultats ont montré que l’exposition de l’hôte à des conditions de stress liées à des scénarios de changement global peut modifier le succès de l’infection parasitaire et altérer les réponse biochimiques de l’hôte.Les résultats présentés dans cette thèse ont amélioré la connaissance des effets de différentes variables sur les bivalves, soulignant le rôle crucial du parasitisme. S’ils sont appliqués, ces nouveaux concepts peuvent promouvoir la gestion durable des bivalves, une ressource marine importante, en augmentant son potentiel de production et donc son potentiel économique
Among population dynamics drivers, parasitism is significant but often neglected. Beyond inventory of the various parasites, it is urgent to understand the susceptibility of hosts, namely bivalves, to infection, and to investigate the interaction among parasites and other environmental conditions.In this way, the present study aimed to characterize and quantify the trematode macroparasites, the most abundant and prevalent in coastal waters, infecting Cerastoderma edule and Donax trunculus, which are among the most ecologically important and economically explored bivalve species in Portugal and France.The first step was to study bivalve population dynamics, evaluating the relationship between temperature and recruitment timing and the reciprocal effects of recruitment on adult biomass. For this, a large database spanning 17 years of monthly observations of a cockle population inhabiting a national protected area (Banc d’Arguin, Arcachon, France) was analysed. Long-term observations showed that the sustainability of a cockle population is recruitment-success dependent. In cockles, recruitment success showed to be partly, but not only, dependent on temperature. Hence, the sustainability of a cohort could be set earlier, i.e. by processes happening before recruitment. Following this clue, the role of parasitism on the bivalve host population dynamics was explored.Firstly, due to high pathogenicity for bivalves, special attention was given to the parasites Bucephalus minimus and Bacciger bacciger which use C. edule and D. trunculus, respectively, as first intermediate hosts (where their sporocysts parasitic stage develops). […]Then, the study focused on metacercariae infection in its bivalve second intermediate host, a relationship that is usually reported as less deleterious. […]Lastly, the susceptibility of bivalves to parasites infection when challenged by climate change related factors (salinity, temperature and pH) and contamination (Arsenic) was experimentally assessed. Main results showed that hosts exposure to stressful conditions related to global change scenarios can modify the parasite infection success and induced host biochemical response alterations.The findings presented in this thesis improved the knowledge on the effects of different constraints on bivalves, highlighting the crucial role of parasitism. If applied, these new insights can promote the sustainable management of bivalves, such an important marine resource, with greater production and economic potential
Entre os agentes que modulam a dinâmica populacional, o parasitismo é significativo masmuitas vezes negligenciado. É urgente não só inventariar as várias espécies de parasitas, bem comocompreender a suscetibilidade dos hospedeiros à infeção (nomeadamente os bivalves) e investigar ainteração entre os parasitas e outras condições ambientais. Pelo que, esta tese teve como objetivoprincipal caracterizar e quantificar os macroparasitas trematodes (os mais abundantes e prevalentesem águas costeiras) que infetam Cerastoderma edule (berbigão) e Donax trunculus (conquilha), doisdos bivalves mais importantes em Portugal e França tanto do ponto de vista ecológico comoeconómico.Primeiramente, a dinâmica populacional dos bivalves foi estudada, tendo em conta a relaçãoentre a temperatura e o período de recrutamento e os efeitos recíprocos do recrutamento nabiomassa de adultos. Para isso, foi analisada uma base de dados abrangendo 17 anos deobservações mensais de uma população de berbigões que habitam uma área nacional protegida(Banc d’Arguin, Arcachon, França). Estas observações de longa duração mostraram que asustentabilidade de uma população de berbigão é dependente do sucesso do recrutamento. Emberbigões, o sucesso do recrutamento mostrou ser em parte, mas não totalmente, dependente datemperatura. Por esta razão, a sustentabilidade de uma coorte pode estar a ser estabelecida maiscedo, isto é, por processos que acontecem antes do recrutamento. Seguindo esta pista, o verdadeiropapel do parasitismo na dinâmica populacional dos bivalves foi mais explorado.De seguida e devido à elevada patogenicidade para os bivalves, foi dada especial atençãoaos parasitas Bucephalus minimus e Bacciger bacciger que usam C. edule e D. trunculus,respetivamente, como primeiros hospedeiros intermediários (onde o estádio parasítico esporocisto sedesenvolve). […].Depois, este estudo focou-se na infeção dos bivalves por metacercariae, ou seja, quandoservem de segundos hospedeiros intermediários no ciclo de vida do parasita. […]Por fim, foi experimentalmente avaliada a suscetibilidade dos bivalves à infeção por parasitasquando desafiados por fatores relacionados com as alterações climáticas (salinidade, temperatura epH) e contaminação (Arsénio). Os resultados mostraram que a exposição dos hospedeiros acondições de stress relacionadas com cenários de alterações globais podem modificar o sucesso dainfeção parasitária e induzir alterações na resposta bioquímica do hospedeiro.As descobertas apresentadas nesta tese melhoraram o conhecimento dos efeitos dediferentes variáveis nos bivalves, salientando o papel crucial do parasitismo. Se aplicados, estesnovos pontos de vista podem promover a gestão sustentável dos bivalves, um recurso marinho tãoimportante, aumentando o seu potencial de produção e económico

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JIKE, WUHE. « Utility of RNA-Seq and bioinformatics for gene discovery and evolutionary analyses in the Arundinoideae (Poaceae) ». Doctoral thesis, Università degli studi di Ferrara, 2019. http://hdl.handle.net/11392/2488068.

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Perennial grass species have been used as renewable resource to produce biofuel, and especially the Arundinoideae, one subfamily of Poaceae perennial grasses has attracted great research attention. Arundo donax L. (also known as the giant reed) is a perennial C3 grass with fast growth. It is considered as the next generation most promising bioenergy and phytoremediation crop in the Mediterranea area. Despite its importance and value, many fundamental aspects of its biology and the precise phylogenetic relationships with respect to other species of the Arundo genus still remain to be fully elucidated. In this PhD thesis I first applied, based on the reference transcriptome of Arundo donax, a computational step-by-step workflow for identifying a total of 141 miRNAs belonging to 14 families and a total of 462 high-confidence predicted targets in A. donax. Among the different miRNA families identified, MIR444 family was commonly expressed in four tissues (bud, culm, root and leaf) in A. donax, indicating it may be related to the high resistance to viruses of these species. Secondly, a total of 235 miRNAs belonging to 37 miRNA families and a total of 175 high-confidence putative targets were identified by using computational approaches in de novo assembly of several Arundo species leaf transcriptomes. Conserved miRNAs tend to regulate homologous targets at conserved target sites in different species. The in depth analysis of the leaf transcriptomes for all taxa of the Arundo genus and closely related outgroups yielded a total of 1,016,877 unigenes with average length ranging from 741 to 1065 bp. Phylogenomic reconstruction based on 150 one-to-one orthologous groups (OGs) showed that A. formosana was sister to the other members of the Arundo genus. The probabilistic models suggested that the ancestral haploid chromosome number of Arundo was thirty-six and revealed that demi-duplication was responsible for the evolutionary increase in chromosome numbers throughout the Arundo genus radiation. In addition, evolutionary analyses identified some genes under positive selection, suggesting their potential for future gene functional validation and improvement of the biomass species A. donax. Lastly, in silico identification and comparative analysis of lignin and cellulose biosynthesis gene families across the Arundinoideae (Poaceae) was carried out. A total of 741 CesA/Csl protein sequences and 1118 lignin biosynthesis proteins were identified from the de novo assemblies of Arundinoideae leaf transcriptomes. Phylogenetic analysis of CesA/Csl proteins showed that CesA/Csl genes classified into 8 clades. CSLA and CSLC subfamily is an independent lineage to other CesA/Csl genes family, indicating that they probably originated from a separate duplication event. Lignin biosynthetic gene were highly divergent between eudicots and monocots, indicating that these genes might have experienced expansion after species differentiation. Further, these gene families divided into different groups based on reference species, namely rice, Arabidopsis and Amborella, indicating that diverse functions might exist in these gene family. The cellulose and lignin biosynthesis genes identified in this study will be helpful for establishing mutagenesis-based reverse genetics and functional genomics approaches in A.donax. In summary, leveraging on the availability of the leaf transcriptomes for all taxa of the Arundo genus and closely related outgroups, and reference transcriptomes of Arundo donax, gene discovery and evolutionary analyses were carried out in this study. These results pave the road to further elucidate the biology and evolution of Arundo donax and other Arundo species. The dissection of the patterns of evolution in Arundo genus will support ongoing efforts to establish reverse genetics and functional genomics approaches in A. donax, thus contributing to provide promising candidate genes for the improvement of this biomass species.
Le Arundinoideae, una sottofamiglia di erbe perenni di Poaceae, ha attirato grande attenzione come risorsa rinnovabile per la produzione di biocarburanti. Arundo donax L. (canna gigante) è un erba perenne di tipo C3 a crescita rapida. È considerata la specie più promettente per produzione di bioenergia e fitodepurazione nella zona mediterranea. Nonostante la sua importanza e valore, molti aspetti fondamentali della sua biologia e le precise relazioni filogenetiche rispetto ad altre specie del genere Arundo restano ancora da chiarire. In questa tesi di dottorato ho dapprima applicato una pipeline computazionale per identificare un totale di 141 miRNA appartenenti a 14 famiglie e un totale di 462 geni target in A. donax. Tra le diverse famiglie di miRNA identificate, la famiglia MIR444 è comunemente espressa in quattro tessuti (gemma, fusto, radice e foglia) in A. donax, indicando che potrebbe essere correlata all'elevata resistenza ai virus di queste specie. In secondo luogo, un totale di 235 miRNA appartenenti a 37 famiglie di miRNA e un totale di 175 target putativi sono stati identificati utilizzando approcci computazionali tramite l'assemblaggio de novo di diversi trascrittomi fogliari di specie del genere Arundo. I miRNA conservati tendono a regolare obiettivi omologhi presso siti bersaglio conservati in diverse specie. L'analisi dei transcrittomi di foglia per tutti i taxa del genere Arundo e outgroup strettamente correlati ha prodotto un totale di 1.016.877 unigenes con una lunghezza media di 741-1065 bp. La ricostruzione filogenomica basata su 150 gruppi ortologhi uno-a-uno (OG) ha dimostrato che A. formosana è la specie sorella degli altri membri del genere Arundo. I modelli probabilistici suggeriscono che il numero aploide di cromosomi ancestrale di Arundo è di 36 e rivela che la semi-duplicazione è stata responsabile dell'aumento evolutivo dei numeri cromosomici in tutto il genere Arundo. Inoltre, le analisi evolutive hanno identificato alcuni geni soggetti a selezione positiva, suggerendo il loro potenziale per il miglioramento della specie da biomassa A. donax. Infine, è stata effettuata l'identificazione in silico e l'analisi comparativa delle famiglie di geni di biosintesi della lignina e della cellulosa nelle Arundinoideae (Poaceae). Un totale di 741 sequenze di proteine CesA / Csl e 1118 proteine di biosintesi della lignina sono state identificate dagli assemblaggi de novo dei trascrittomi di foglie di Arundinoideae. L'analisi filogenetica delle proteine CesA / Csl ha dimostrato che i geni CesA / Csl sono classificati in 8 cladi. Le sottofamiglie CSLA e CSLC sono una linea evolutiva indipendente rispetto ad altre famiglie di geni CesA / Csl, indicando che probabilmente hanno avuto origine da un evento di duplicazione separato. I geni biosintetici della lignina sono altamente divergenti tra eudicotiledoni e monocotiledoni, indicando che questi geni potrebbero essere andati incontro ad espansione dopo la differenziazione delle specieInoltre, queste famiglie di geni si dividono in diversi gruppi basati sulle specie di riferimento, indicando che potrebbero esistere diverse funzioni in questa famiglia di geni. I geni identificati in questo studio saranno utili per stabilire approcci di genomica funzionale e di genetica inversa basati sulla mutagenesi in A.donax. In sintesi, facendo leva sulla disponibilità dei trascrittomi fogliari per tutti i taxa del genere Arundo, in questo studio sono stati condotti sia la scoperta genica che l’analisi evolutiva in Arundinoidee. Questi risultati aprono la strada per chiarire ulteriormente la biologia e l'evoluzione di Arundo donax e di altre specie di Arundo. La dissezione dei modelli di evoluzione nel genere Arundo sosterrà gli sforzi in corso per metter a punto gli approcci di genetica inversa e genomica funzionale in A. donax, contribuendo così a fornire promettenti geni candidati per il miglioramento di questa specie da biomassa.

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Escrivá, Perales Julia. « Estudio de los bancos explotables de Donax trunculus y Chamelea gallina en el sector sur del Golfo de Valencia y factores ambientales que influyen en su abundancia ». Doctoral thesis, Universitat Politècnica de València, 2020. http://hdl.handle.net/10251/134365.

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[ES] Las playas arenosas son ambientes muy dinámicos e inestables que presentan una gran variedad de formas de vida y en algunas zonas una gran productividad. En el golfo de Valencia, encontramos dos especies de bivalvos con elevado interés comercial, como son Donax trunculus y Chamelea gallina, los cuales forman parte del mismo métier. Gandia es un área clave para la pesquería artesanal de ambas especies en el golfo de Valencia. No obstante, en la última década las capturas de ambas especies han sufrido una fuerte disminución, lo que condujo al cierre de la pesquería en junio de 2015. Por ello, el objetivo principal de la presente tesis fue analizar la pesquería del métier compuesto por D. trunculus y C. gallina en el área de trabajo de la Cofradía de Pescadores de Gandia, que abarca desde Tavernes de la Valldigna a Denia, hasta su cierre, la evolución de las poblaciones de D. trunculus tras el mismo, así como los factores ambientales que pudieron afectar a los bancos de ambas especies y del resto de organismos de la biocenosis del sublitoral de playas arenosas. En Gandia, las capturas, la flota pesquera y CPUE del métier estudiado, en el que domina D. trunculus, sufrieron una fuerte disminución durante el período 2004-2014, volviéndose más abrupta a partir de los años 2009 y 2010. Las capturas de D. trunculus disminuyeron de 100 000 kg en 2004 a 1600 kg en 2014, y de 21 000 en el 2007 a 800 en el 2014 para C. gallina. Además, esta pesquería presentó una marcada estacionalidad con incrementos de captura en primavera-verano y una mayor presión pesquera en las zonas ubicadas al sur del puerto de Gandia. Los parámetros de crecimiento de D. trunculus obtenidos mostraron algunas diferencias con los estudios de otras áreas geográficas, destacando que los valores obtenidos para la longitud asintótica y la constante de crecimiento en el año 2015 fueron más bajos que los obtenidos 25 años antes en la misma región. Además, la población de D. trunculus mostró una distribución diferencial de tamaños entre las profundidades y un período de reclutamiento en verano. La fauna bentónica mostró una clara zonación batimétrica definida fundamentalmente por el tamaño medio del sedimento y la cantidad de materia orgánica. Se encontró una comunidad dominada por un mayor tamaño de grano medio y menor contenido en materia orgánica, en la zona más somera y turbulenta, en la que dominó en biomasa el bivalvo D. trunculus. Y otra comunidad sujeta al mayor contenido de materia orgánica en el sedimento y un tamaño de grano más fino, presente a mayor profundidad, en la que los fondos son más estables, dominada por poliquetos depositívoros y en la que se desarrolla C. gallina. La macrofauna bentónica siguió una pauta temporal con máximos de abundancia en verano que no fue tan patente en D. trunculus y C. gallina debido a su explotación. Los valores de densidad y biomasa obtenidos dos años después del cierre, no solo mostraron que no había habido una recuperación de la población, sino también que la situación había empeorado. Por lo tanto, el cierre de la pesquería no tuvo el efecto deseado a corto plazo. La sobreexplotación que sufrieron los bancos de D. trunculus y C. gallina podría haber agravado los efectos adversos provocados por otros factores dificultando así la recuperación de las poblaciones. Finalmente, es importante destacar que las deficiencias en los planes de manejo de esta pesquería propiciaron la sobreexplotación y que el cierre de la pesquería ya colapsada no permitió su recuperación a corto plazo.
[CAT] Les platges arenoses són ambients molt dinàmics i inestables que presenten una gran varietat de formes de vida i en algunes zones una gran productivitat. En el golf de València, trobem dues espècies de bivalves amb elevat interès comercial, com són Donax trunculus i Chamelea gallina, els quals formen part del mateix métier. Gandia és una àrea clau per a la pesqueria artesanal de les dues espècies al golf de València. No obstant això, en l'última dècada les captures de les dues espècies han patit una forta disminució, el que va conduir al tancament de la pesqueria al juny de 2015. Per això, l'objectiu principal de la present tesi va ser analitzar la pesqueria del métier compost per D. trunculus i C. gallina a l'àrea de treball de la Confraria de Pescadors de Gandia, que va des de Tavernes de la Valldigna a Dénia, fins al seu tancament, l'evolució de les poblacions de D. trunculus després del mateix, així com els factors ambientals que van poder afectar els bancs d'ambdues espècies i de la resta d'organismes de la biocenosi del sublitoral de platges arenoses. A Gandia, les captures, la flota pesquera i CPUE del métier estudiat, en què domina D. trunculus, van patir una forta disminució durant el període 2004-2014, tornant-se més abrupta a partir dels anys 2009 i 2010. Les captures de D. trunculus van disminuir de 100 000 kg en 2004 a 1600 kg al 2014, i de 21 000 en 2007 a 800 al 2014 per a C. gallina. A més, aquesta pesqueria va presentar una marcada estacionalitat amb increments de captura en primavera-estiu i una major pressió pesquera a les zones situades al sud del port de Gandia. Els paràmetres de creixement de D. trunculus obtinguts van mostrar algunes diferències amb els estudis d'altres àrees geogràfiques, destacant que els valors obtinguts per a la longitud asimptòtica i la constant de creixement en l'any 2015 van ser més baixos que els obtinguts 25 anys abans a la mateixa regió. A més, la població de D. trunculus va mostrar una distribució diferencial de grandàries entre les profunditats i un període de reclutament a l'estiu. La fauna bentònica va mostrar una clara zonació batimètrica definida fonamentalment per la grandària mitja del sediment i la quantitat de matèria orgànica. Es va trobar una comunitat dominada per una major grandària de gra mitjà i menor contingut en matèria orgànica, a la zona més somera i turbulenta, en la que va dominar en biomassa el bivalve D. trunculus. I una altra comunitat subjecta al major contingut de matèria orgànica en el sediment i una mida de gra més fi, present a més profunditat, en la qual els fons són més estables, dominada per poliquets depositívoros i en la que es desenvolupa C. gallina. La macrofauna bentònica va seguir una pauta temporal amb màxims d'abundància a l'estiu que no va ser tan patent en D. trunculus i C. gallina a causa de la seva explotació. Els valors de densitat i biomassa obtinguts dos anys després del tancament, no només van mostrar que no hi havia hagut una recuperació de la població, sinó també que la situació havia empitjorat. Per tant, el tancament de la pesqueria no va tenir l'efecte desitjat a curt termini. La sobreexplotació que van patir els bancs de D. trunculus i C. gallina podria haver empitjorat els efectes adversos provocats per altres factors dificultant així la recuperació de les poblacions. Finalment, és important destacar que les deficiències en els plans de gestió d'aquesta pesqueria van propiciar la sobreexplotació i que el tancament de la pesquera ja col·lapsada no va permetre la seva recuperació a curt termini.
[EN] Sandy beaches are very dynamic and unstable environments that present a wide variety of life forms and in some areas high productivity. In the Gulf of Valencia, we can find two species of bivalves with high commercial interest, such as Donax trunculus and Chamelea gallina, which are part of the same métier. Gandia is a key area for the artisanal fishery of both species in the Gulf of Valencia. However, in the last decade the catches of both species have suffered a sharp decrease, which led to the closure of the fishery in June 2015. Therefore, the main objective of this thesis was to analyse the méterier composed by D. trunculus and C. gallina in the Gandia Fishermen's Guild work area, which covers from Tavernes de la Valldigna to Denia, until its closure, the evolution of the populations of D. trunculus after it, as well as the environmental factors which could affect the beds of both species and the rest of the sublittoral organisms of the sandy beach. In Gandia, the catches, the fishing fleet and CPUE of the studied métier, in which D. trunculus dominates, suffered a sharp decrease during the period 2004-2014, becoming more abrupt from 2009 and 2010. The catches of D. trunculus decreased from 100 000 kg in 2004 to 1600 kg in 2014, and for C. gallina from 21 000 in 2007 to 800 in 2014. In addition, this fishery showed a marked seasonality with catches and fishing effort peaks in spring-summer and greater fishing pressure in the areas located south of Gandia Port. The growth parameters of D. trunculus obtained showed some differences to other studies from different geographical areas, highlighting that the values obtained for asymptotic length and growth constant in 2015 were lower than those obtained 25 years earlier in the same region. In addition, the population of D. trunculus showed size differential distribution between depths and a period of recruitment in summer. The benthic fauna showed a clear bathymetric zonation explained primarily by the mean grain size of the sediment and the amount of organic matter. A community was found dominated by a larger mean grain size and lower organic matter content, in the shallowest and turbulent zone, in which the bivalve D. trunculus dominated in biomass. And another community related to the higher content of organic matter in the sediment and a finer grain size present in greater depth, in which the bottom is more stable, dominated by deposit feeder polychaetes and in which C. gallina develops. The macrobenthic fauna showed a temporary pattern with highs abundances in summer that was not so evident in D. trunculus and C. gallina due to its exploitation. The density and biomass values obtained two years after the closure, not only showed that there had not been a population recovery, but also that the situation had worsened. Therefore, the closure of the fishery had not had the desired effect in the short term. The overexploitation suffered in D. trunculus and C. gallina beds could have aggravated the adverse effects caused by other factors, thus hindering the recovery of populations. Finally, it is important to note that the deficiencies in the fishery's management plans led to overexploitation and that the closure of the already collapsed fishery did not allow its recovery in the short term.
Escrivá Perales, J. (2019). Estudio de los bancos explotables de Donax trunculus y Chamelea gallina en el sector sur del Golfo de Valencia y factores ambientales que influyen en su abundancia [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/134365
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Yamaç, S. S. « DEVELOPMENT AND EVALUATION OF A DETAILED, PROCESS-BASED CROP MODEL FOR GIANT REED ». Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/232863.

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The aim of the thesis is the development of a process-based model for the simulation of giant reed growth and productivity under a variety of climatic and management conditions. Arundo donax L. (giant reed) is a perennial C3 grass native to Asia and naturalized to the Mediterranean area. Being part of the second generation biofuel crop (i.e., non-food, cellulosic biomass feedstock for ethanol or combustion), Arundo d. is characterized by high yield potential with low requirements in terms of soil, fertilizers, and water. Therefore giant reed is attracting interest as an alternative energy source and dedicated research studies are continuously increasing. The re-implementation of the sugarcane (Saccharum officinarum L.) model Canegro (DSSAT v4.5) in a framework-independent component was starting point for the development of the Arundo donax L. model (i.e., Arungro). The Canegro component was effectively extended and adapted for giant reed because of several morphological and physiological features shared with sugarcane. The newly developed Arungro model was calibrated and evaluated by means of two dedicated field monitoring under a number of crop ages and management conditions. The model performed reasonably well especially for the estimation of the aboveground biomass. The investigation of the impact of climate change on Arundo donax L. production was carried out by applying the Arungro model in a case study area in the Po valley area. This was the first attempt in evaluating future non-feed and non-food crop productivity.

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Jakobi, Rainer. « Die Kunst der Exegese im Terenzkommentar des Donat / ». Berlin ; New York : W. de Gruyter, 1996. http://catalogue.bnf.fr/ark:/12148/cb369929477.

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Karlsson, Axel, et Pinthira Fagerström. « Blue Growth : Applications and properties of biochar made out of reed ». Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297368.

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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, geographical differences, different unit measuring and methodology. The potential for biochar in the coal market is high and the demand in Sweden has risen over the past couple of years. There is also interest in using biochar as a soil amendment, to make use of nutrient content as well as applying organic matter to soils to potentially achieve long-term carbon sequestration. However, the production cost of biochar out of reed is relatively expensive, and it cannot compete with coal or other fertilisers/soil amendments on the market, with feedstock management usually being the most expensive part of production. Lastly, there is currently no harvesting method that can measure the amount of reed that needs to be harvested to be able to produce biochar on a large scale.
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 finns kunskapsluckor, geografiska skillnader, olika måttenheter och metoder för de studier som gjorts inom detta område. Potentialen för biokol på kolmarknaden är hög och efterfrågan i Sverige har ökat de senaste åren. Det finns också intresse för att använda biokol för jordförbättring, dels för att använda näringsinnehållet men också för att applicera biokol i jorden för att potentiellt uppnå långvarig kolbindning. Dock är produktionskostnaden för biokol gjort på vass mycket kostsam och kan därför inte konkurrera med fossilt kol eller andra gödselmedel jordförändringar på marknaden. Detta beror främst på råvaruhanteringen som är den dyraste delen av produktionen. Slutligen finns det för närvarande ingen skördemetod som kan mäta den mängd vass som behöver skördas för att kunna producera biokol i stor skala.

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Pérez, Pérez Isabel. « Dona i jubilació ». Doctoral thesis, Universitat Rovira i Virgili, 2011. http://hdl.handle.net/10803/51756.

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La finalitat de la tesi rau en cercar coneixement sobre la transició de la jubilació de dones jubilades, i aportar aquest coneixement a la disciplina infermera per tal que els seus professionals puguin establir criteris i dissenyar programes de salut específics que millorin les cures infermeres que se’ls poden oferir, en aquesta etapa de la vida, des de l’Atenció Primària de Salut (APS). Es planteja com a objectiu descriure la jubilació de les dones que han participat en l’estudi, i per fer-ho des d’aquest horitzó d’una futura atenció infermera, calia analitzar el elements identificats que caracteritzen el seu procés a la llum de referents teòrics que, entre d’altres, contemplessin la perspectiva infermera, d’aquí que un dels punts importants del marc teòric hagi estat la Teoria de les Transicions de Meleis. L’estudi està acotat geogràficament a Catalunya, i en concret es circumscriu a la ciutat de Barcelona. S’ha seleccionat aquesta ciutat per la representativitat de les seves dades, ja que, segons l’anuari d’envelliment de Catalunya (2004), la taxa de sobreenvelliment al nostre país es concentra sobretot en els municipis de més de 500.000 habitants, i un total del 30% es localitzen només a la ciutat de Barcelona. La recerca s’aborda des del paradigma qualitatiu en estar orientat vers la comprensió i interpretació dels significats i accions des de la pròpia perspectiva de les dones jubilades. En el procés de recollida de les dades, la tècnica dels grups de discussió ha estat el nucli central del treball de camp. L’anàlisi de les dades s’ha realitzat mitjançant el procediment de l’Anàlisi de Contingut en la seva concepció més tradicional.
La finalidad de la tesis es obtener conocimiento sobre la transición de la jubilación de mujeres jubiladas, y aportar este conocimiento a la disciplina enfermera para que sus profesionales puedan establecer criterios y diseñar programas de salud específicos que mejoren los cuidados enfermeros que se les pueden ofrecer, en esta etapa de la vida, desde la Atención Primaria de Salud (APS). Se plantea como objetivo describir la jubilación de las mujeres que han participado en el estudio, y para hacerlo desde el horizonte de una futura atención enfermera, era necesario analizar los elementos identificados que caracterizan este proceso a la luz de referentes teóricos que, entre otros, contemplen la perspectiva enfermera, de aquí que uno de los puntos importantes del marco teórico haya sido la Teoría de las Transiciones de Meleis. El estudio está acotado geográficamente en Cataluña, y en concreto se circunscribe a la ciudad de Barcelona. Se ha seleccionado esta ciudad por la representatividad de sus datos, ya que, según el anuario de envejecimiento de Cataluña (2004), la tasa de sobre envejecimiento en nuestro país se concentra sobre todo en los municipios de más de 500.000 habitantes, y un total del 30% se localizan en la ciudad de Barcelona. La investigación se aborda desde el paradigma cualitativo al orientarse a la comprensión e interpretación de los significados y acciones desde la propia perspectiva de las mujeres jubiladas. En el proceso de recogida de los datos, la técnica de los grupos de discusión ha sido el núcleo central del trabajo de campo. El análisis de los datos se ha realizado mediante el procedimiento del Análisis de Contenido en su concepción más tradicional.

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David, Isabel. « Altenpflegezentrum Mühlheim an der Donau ». [S.l. : s.n.], 2005. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11730097.

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Donat, Johannes [Verfasser]. « Epilepsie - Szientometrische Analysen / Johannes Donat ». Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2009. http://d-nb.info/1023818086/34.

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Reschke, Stephan. « Biogeochemie der Schwebstofffracht der Donau und deren Einfluss auf das Sedimentationsgeschehen im nordwestlichen Schwarzen Meer ». [S.l. : s.n.], 1999. http://www.sub.uni-hamburg.de/disse/190/Disse.pdf.

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Priester, Maike [Verfasser], Donat [Akademischer Betreuer] Kögel et Anna [Akademischer Betreuer] Starzinski-Powitz. « Die Rolle von Stat3 in Gliomen / Maike Priester. Gutachter : Donat Kögel ; Anna Starzinski-Powitz. Betreuer : Donat Kögel ». Frankfurt am Main : Univ.-Bibliothek Frankfurt am Main, 2012. http://d-nb.info/1044772514/34.

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Cruz, Lanuzza Gama. « DONA FLOR : SABOR E ARTE ». Pontifícia Universidade Católica de Goiás, 2014. http://localhost:8080/tede/handle/tede/3239.

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Made available in DSpace on 2016-08-10T11:07:12Z (GMT). No. of bitstreams: 1 LANUZZA GAMA CRUZ.pdf: 752949 bytes, checksum: 4cc58f4600bd92cee83c5056980379dd (MD5) Previous issue date: 2014-09-26
This Master´s thesis has the objective to analyze the romance, Dona Flor e seus dois maridos, written by Jorge Amado and published in 1966.The analysis focus on character , and dream and hybridization, articulated concepts with carnivalization in literature, fruit of studies from Mikhail Bakhtin, Roberto DaMatta and Luis Alberto Warat between others, which contributes for the comprehension of "world upside down , focused on research of carnivalization elements in the work in question and represented in three characters: Vadinho, Dona Flor e Teodoro. The present universe in this work reveals a world that escapes the usual standards of morality imposed by the epoch system, the dictatorship.
Esta dissertação tem por objetivo analisar o romance, Dona Flor e seus dois maridos, escrito por Jorge Amado e publicado em 1966. A análise tem como suporte conceitual personagem, sonho e hibridização, conceitos articulados com a carnavalização da narrativa literária, fruto dos estudos de Mikhail Bakhtin, Roberto DaMatta, Affonso Romano de Sant Anna, Georges Bataille e Luis Alberto Warat e Luis Alberto Warat entre outros, que contribuem para a compreensão do mundo às avessas , centrado na pesquisa dos elementos carnavalizantes na obra em questão e representado por meio das personagens: Vadinho, Dona Flor, Teodoro e Dona Rozilda. O universo presente nesta obra em estudo revela um mundo que foge aos padrões habituais de moralidade, impostos pelo sistema da época, a ditadura.

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Hashemi, Seyed Mohammad Amin [Verfasser], Donat [Akademischer Betreuer] Kögel et Georg [Akademischer Betreuer] Auburger. « Molekulare Mechanismen der S100B-vermittelten Neuroprotektion / Seyed Mohammad Amin Hashemi. Gutachter : Donat Kögel ; Georg Auburger. Betreuer : Donat Kögel ». Frankfurt am Main : Univ.-Bibliothek Frankfurt am Main, 2013. http://d-nb.info/1043978402/34.

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Hashemi, Seyed Mohammad Amin [Verfasser], Donat Akademischer Betreuer] Kögel et Georg [Akademischer Betreuer] [Auburger. « Molekulare Mechanismen der S100B-vermittelten Neuroprotektion / Seyed Mohammad Amin Hashemi. Gutachter : Donat Kögel ; Georg Auburger. Betreuer : Donat Kögel ». Frankfurt am Main : Univ.-Bibliothek Frankfurt am Main, 2013. http://nbn-resolving.de/urn:nbn:de:hebis:30:3-316307.

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Cramer-Fürtig, Michael. « Landesherr und Landstände im Fürstentum Pfalz-Neuburg : Staatsbildung und Ständeorganisation in der ersten Hälfte des 16. Jahrhunderts / ». München : C.H. Beck'sche Verlagsbuchhandlung, 1995. http://catalogue.bnf.fr/ark:/12148/cb37037853f.

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Thies, Birgit. « Instationarität und räumliche Variabilität in Abflusszeitreihen aus Süddeutschland ». Bayreuth Bayreuth Center of Ecology and Environmental Research, 2009. http://d-nb.info/997454466/34.

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Weigt, Gabriele. « Erlebnispfad an der Jungen Donau längster Erlebnispfad am längsten Fluss Mitteleuropas / ». [S.l. : s.n.], 2004. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11244216.

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Thèses sur le sujet « A. donax »

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