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Analysis of an aerobic membrane bioreactor with the application of event detection software and variable operational filtration modesLeow, Aaron S. January 2015 (has links)
No description available.
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First season effects of managed flooding on the invasive species Phalaris arundinacea L. and shoreline vegetation communities in an urban wetlandJenkins, Noah John 01 January 2005 (has links)
Recent management efforts in the Smith and Bybee Lakes Wildlife Area (SBL), a 700-ha preserve in north Portland, Oregon, have included using a water control structure to suppress invasive reed canarygrass (Phalaris arundinacea L.) by flooding during spring and early summer growth periods. For the first year of managed flooding, I sought to determine: (a) the extent and distribution of reed canarygrass at SBL; (b) the effectiveness of the change in water level at suppressing reed canarygrass; and ( c) the effects of the change in water level on other plant species.
I established 30 vegetation transects throughout SBL before completion of the water control structure. These transects were randomly distributed, placed perpendicularly to the shorelines of the wetlands, and had a cumulative length of 3.1 km. I measured vegetation on the transects in autumn 2003 and autumn 2004 using the line intercept method at 10-cm intervals. I surveyed the transects to generate elevation profiles, accurate to 0.15 cm, to determine depth and duration of flooding, which I correlated with vegetative changes. I also monitored inundation depth, growth, and phenological response of individual stands of reed canarygrass during the 2004 growing season.
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Historical eruptions of Lanzarote, Canary Islands : Inference of magma source and melt generation from olivine and its melt inclusions / Les éruptions historiques de Lanzarote, Iles Canaries : contribution des inclusions vitreuses à la compréhension de la formation des liquides primitives et leur sourcesGomez-Ulla Rubira, Alejandra 25 September 2018 (has links)
L’étude des basaltes des îles océaniques (OIB) révèle la complexité du manteau terrestre, dont la composition chimique est hautement variable. Décrypter l’implication des lithologies des roches sources et des processus à l’origine des OIB est complexe car les magmas sont transformés lors de leur ascension jusqu’à la surface. Ceci est particulièrement critique dans le cas des îles Canaries, où la lithosphère est considérée comme particulièrement épaisse (>110 km Fullea et al., 2015). Afin de mieux contraindre la composition chimique des magmas primitifs et les lithologies mantelliques plausiblement impliquées, deux éruptions historiques de l’île de Lanzarote, les éruptions de Timanfaya (1730-1736) et celles de 1824, ont été étudiées. En effet, ces deux éruptions offrent une opportunité unique d’étudier les mécanismes de génération des magmas et leurs compositions dans un contexte où le manteau est hétérogène. L’éruption de historique de Timanfaya (1730-1736) a émis des magmas qui ont évolué de basanites à basaltes alcalins, pour atteindre des compositions tholeitiques à la fin de l’éruption. La dernière éruption de l’île, en 1824, a produit des basanites extrêmement riches en volatils. L’hétérogénéité du manteau est démontrée à l’extrême à Lanzarote où une seule éruption présente une variation de compositions chimiques équivalente à la diversité de celles des OIB dans le monde. L’extrême hétérogénéité est systématique pour les compositions des roches totales et des téphras à l’échelle d’une éruption, mais est encore amplifiée à l’échelle du minéral et des inclusions magmatiques contenus dans un même échantillon de téphra.Les concentrations des éléments traces et leurs rapports dans l’olivine (e.g. Ni, Mn et Ca) sont de précieux marqueurs des lithologies mantelliques à l’origine des magmas. En effet, les rapports Ni x (FeO/MgO), corrigé du fractionnement, et Fe/Mn sont des indicateurs de lithologies avec ou sans olivines. Il est considéré qu’ils peuvent montrer, dans la plupart des cas, l’ajout d’un liquide magmatique dérivé d’une pyroxénite dans les magmas primaires. La mesure des compositions des éléments traces des olivines des éruptions de 1730-1736 et de 1824 montrent les implications variables de plusieurs lithologies mantelliques au cours du temps. Lors de la fusion d’une lithologie ne contenant pas d’olivines, comme la pyroxénite, de hautes teneurs en Ni et de faibles teneurs en Mn et Ca sont attendues. Les basanites de Lanzarote présentent les plus grandes variations géochimiques, couvrant le champ compositionnel des olivines des MORB et des OIB du monde entier, tandis que les produits plus tardifs, c’est-à-dire les basaltes alcalins et les tholéites, ont des teneurs typiques de liquides magmatiques dérivés de pyroxénites. Les teneurs en forstérite (Fo) des olivines diminuent systématiquement avec le temps durant l’éruption de 1730-1736 et la proportion de liquide primaire saturé en silice augmente dans les mélanges de magmas primitifs avec le temps. A la fin de l’éruption, les magmas tholéitiques cristallisent des olivines dont la teneur en Fo est faible, alors que les concentrations en Mn et Ca augmentent simultanément avec le rapport Ca/Al pour des rapports Fe/Mn et Ni x (FeO/MgO) relativement constants. Ces observations sont expliquées par une augmentation de la fusion par décompression à température légèrement plus faible. D’autre part, les basanites de l’éruption de 1824 possèdent les olivines ayant les teneurs en Fo les plus élevées, et des teneurs en éléments traces dépassant la variabilité des basanites de l’éruption de Timanfaya. Le fait que les basanites de Lanzarote contiennent des olivines dont les compositions en éléments traces recouvrant le champ des MORB et des liquides pyroxènitiques est expliqué par la fusion d’une source contenant des lithologies hétérogènes, induite par un flux de CO2, générant ainsi des magmas aux compositions diverses. (...) / The study of oceanic island basalts (OIB) reveals the complexity of the mantle, which composition is highly variable. Deciphering the source lithologies and processes involved in the OIB formation is challenging since the magmas are transformed on their way to the surface. This is especially critical at Canary Islands where the lithosphere is thought to be remarkably thick (>110 km Fullea et al., 2015). In order to better constrain the composition of primitive magmas and the plausible mantle lithologies involved, two historical eruptions recorded at Lanzarote island, Timanfaya 1730-1736 and 1824 eruptions have been investigated. Indeed, these two eruptions offer a unique opportunity to investigate the mechanisms of magma generation and composition in the context of mantle heterogeneity. The Timanfaya, 1730-1736 historical eruption emitted magmas that evolved from basanites through alkali basalts, finally reaching tholeiitic compositions at the end of the eruption. In 1824 the last eruption on the island produced extremely volatile-rich basanite. The heterogeneity of the mantle is demonstrated to the extreme in Lanzarote where a single eruption exhibits compositional variations similar to the span of the OIB worldwide. The extreme heterogeneity is systematic from whole rock lava and tephra at eruption scale but amplified at mineral and melt inclusion scale within a single tephra sample of the eruption.The use of trace element concentrations and ratios of olivine (e.g. Ni, Mn, and Ca) are valuable indicators of the mantle source lithology, namely, the fractionation-corrected Ni x (FeO/MgO) and Fe/Mn as probes of olivine absent or present lithologies, often taken as pyroxenite-derived component in mixtures of primary melts. The measured trace element concentrations in olivine from the 1730-1736 and 1824 eruptions reveal variable mantle lithologies involved in the magma generation with time. Higher Ni and lower Mn and Ca contents are expected when melting Ol-free source, such as pyroxenite lithologies. The basanites exhibit the largest variation covering the range of olivine in MORB and OIB worldwide whereas later produced alkali-basalts and tholeites have values typically expected from pyroxenite derived melts. The Fo content decreases systematically with time during the 1730-36 eruption and the proportion of silica-saturated primary melt increased in the parental magma mixture with time. At the end of the eruption, tholeiite magmas crystallized olivine with lower Fo content, whereas those concentrations of Mn and Ca increased together with Ca/Al at relatively uniform Ni x (FeO/MgO) and Fe/Mn, all of which is readily explained by increased decompression melting at slightly lower temperature. The basanite from the eruption that took place in 1824 has olivine with the highest Fo content and trace element variability expanding the range of the Timanfaya basanite. The fact that Lanzarote basanites contain olivine with trace element systematic spanning that of MORB and pyroxenite melt is explained by CO2-flux melting of a lithologically heterogeneous source, generating the diverse compositions. In addition, early reactive porous flow through the depleted oceanic lithosphere and equilibration with harzburgite restite caused Ni depletion of the earliest percolating pyroxenite melt from which olivine crystallized and probably leaving dunite channels. After the channel formation mantle nodules could be brought to the surface. The fact that olivine compositions and basanite magma were reproduced approximately a century later may reflect episodic carbonatic fluxing in the slowly uprising Canarian mantle plume. (...)
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Žolinių augalų panaudojimas kietajam biokurui / Herbal plants use for solid biofuelNavadvorskytė, Justina 04 February 2013 (has links)
Šio magistro baigiamojo darbo tikslas buvo ištirti trijų energetinių žolinių augalų biometrines bei energetines savybes ir jas palyginti tarpusavyje. Augalai buvo auginami lauko sąlygomis, kiekvieną augalą tręšiant skirtingomis mineralinio azoto normomis (N0 – kontrolė, N60 – 200 kg ha-1 ir N120 – 400 kg ha-1). Buvo tiriami pagrindiniai biometriniai rodikliai: augalų aukštis, augalų stiebų skaičius, sausoji biomasė, chlorofilo indeksas. Taip pat ištirtas pasirinktų augalų šilumingumas, peleningumas, pagrindiniai elementai (C, H, N, S, O) bei šalutiniai elementai (K, Ca, Mg, P, Al, Si, S), taip pat sunkieji metalai. Visų augalų energetinės savybės palygintos tarpusavyje. Vertinant gautus duomenis, tinkamiausi žoliniai augalai biokurui yra sida ir drambliažolė, kadangi jų peleningumas yra mažiausias. Tačiau nendrinio dryžučio, nors ir išsiskyrė didesniu peleningumu, šilumingumas buvo didžiausias. Cheminės sudėties analizės metu buvo nustatyta, jog papildomas tręšimas azotinėmis trąšomis įvairių elementų kiekiui augaluose didelės įtakos neturėjo, tačiau vertinant šalutinių elementų kiekį augaluose pastebėta tai, jog kai kurių cheminių elementų padidėjimą galėjo lemti ir augalų augimo vieta (atvira pieva, šalia žvyrkelio, šalia kelio, šalia dirbamo lauko ir pan.). / This master's thesis was to analyze three energy plant grass biometric and energy properties and to compare them with each other. Plants were grown in field, every plant fertilized with different rates of nitrogen (N0 - control, N60 - 200 kg ha-1 and N120 - 400 kg ha-1). It was investigated the main biometric parameters: plant height, plant stems, dry biomass and chlorophyll index. Also plants calorific value, ash content, the main elements (C, H, N, S, O) and minor elements (K, Ca, Mg, P, Al, Si, S) and heavy metals. Plant‘s energy properties were compared with each other. Evaluating the data, the optimum herbaceous plant for biofuels are sida and Miscanthus as their ash content is lowest. Reed canary grass calorific value was highest, but it stood higher ash content too. Chemical composition analysis showed that the additional nitrogen fertilization had no major impact of the various elements in plants, but by assessing the amount of elements in plants is noticeable that plant growth and position may impact some chemical elements increase (open meadow, near the gravel, next to the road, arable land, etc.).
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Žolinių augalų panaudojimas kietajam biokurui / Herbal plants use for solid biofuelNavadvorskytė, Justina 04 February 2013 (has links)
Šio magistro baigiamojo darbo tikslas buvo ištirti trijų energetinių žolinių augalų biometrines bei energetines savybes ir jas palyginti tarpusavyje. Augalai buvo auginami lauko sąlygomis, kiekvieną augalą tręšiant skirtingomis mineralinio azoto normomis (N0 – kontrolė, N60 – 200 kg ha-1 ir N120 – 400 kg ha-1). Buvo tiriami pagrindiniai biometriniai rodikliai: augalų aukštis, augalų stiebų skaičius, sausoji biomasė, chlorofilo indeksas. Taip pat ištirtas pasirinktų augalų šilumingumas, peleningumas, pagrindiniai elementai (C, H, N, S, O) bei šalutiniai elementai (K, Ca, Mg, P, Al, Si, S), taip pat sunkieji metalai. Visų augalų energetinės savybės palygintos tarpusavyje. Vertinant gautus duomenis, tinkamiausi žoliniai augalai biokurui yra sida ir drambliažolė, kadangi jų peleningumas yra mažiausias. Tačiau nendrinio dryžučio, nors ir išsiskyrė didesniu peleningumu, šilumingumas buvo didžiausias. Cheminės sudėties analizės metu buvo nustatyta, jog papildomas tręšimas azotinėmis trąšomis įvairių elementų kiekiui augaluose didelės įtakos neturėjo, tačiau vertinant šalutinių elementų kiekį augaluose pastebėta tai, jog kai kurių cheminių elementų padidėjimą galėjo lemti ir augalų augimo vieta (atvira pieva, šalia žvyrkelio, šalia kelio, šalia dirbamo lauko ir pan.). / This master's thesis was to analyze three energy plant grass biometric and energy properties and to compare them with each other. Plants were grown in field, every plant fertilized with different rates of nitrogen (N0 - control, N60 - 200 kg ha-1 and N120 - 400 kg ha-1). It was investigated the main biometric parameters: plant height, plant stems, dry biomass and chlorophyll index. Also plants calorific value, ash content, the main elements (C, H, N, S, O) and minor elements (K, Ca, Mg, P, Al, Si, S) and heavy metals. Plant‘s energy properties were compared with each other. Evaluating the data, the optimum herbaceous plant for biofuels are sida and Miscanthus as their ash content is lowest. Reed canary grass calorific value was highest, but it stood higher ash content too. Chemical composition analysis showed that the additional nitrogen fertilization had no major impact of the various elements in plants, but by assessing the amount of elements in plants is noticeable that plant growth and position may impact some chemical elements increase (open meadow, near the gravel, next to the road, arable land, etc.).
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Plasticité individuelle : influence du statut social et de l’ontogenèse chez le canari domestique, serinus canariaBouillet, Ophélie 20 December 2013 (has links)
Cette étude a demontré l’influence du statut social sur différentes caractéristiques individuelles telles que le chant, la personnalité ou les capacités cognitives chez le canari domestique commun, Serinus canaria. Celui-ci associé à la familiarité jouent un rôle non négligeable dans les stratégies de fourragement. Il est considéré comme étant un trait de personnalité. L’existence de syndromes comportementaux et l’influence de la photopériode sur les différents traits répétables de personnalité ont également été mis en évidence. L’ontogénèse des individus, à savoir les conditions acousiques de développement a une influence sur les profils comportementaux. Ces derniers semblent liés à la production vocale telle que le chant, ainsi qu’avec les capacités cognitives à savoir l’apprentissage d’une tâche de recherche alimentaire. Le statut social semble également avoir un impact sur la cognition chez les canaris domestiques communs. Néanmoins aucun résultat n’a pu mettre en évidence la relation entre les différentes caractéristiques individuelles et le rythme cardiaque.cette recherche en thèse s'inscrit dans un projet sous administration de l'université franco-allemande en partenariat (collège doctoral franco-allemand) avec l'institut max planck. elle tend à montrer l'influence du contexte social, du statut social et de l'ontogenèse sur une manifestation comportementale propre à l'individu à savoir son chant. notre modèle, le canari domestique commun mâle possède son propre répertoire de chants et de syllabes et cette étude vise à mettre en évidence les différences inter individuelles qui sont le jeu des tendances comportementales sous influence de l'environnement et sans influence de cet environnement. nous supposons qu'un individu subordonné évoluant dans un contexte pauvre aura une production vocale plus simple qu'un individu dominant ayant évolué dans un contexte complexe (production exprimée par le nombre de types syllabiques utilisés et par la longueur des chants dans différentes conditions). nous présumons que les conditions ontogénétiques qui mènent à des répertoires de tailles différentes influencent notablement les habiletés d'apprentissage du chant et la plasticité des adultes. / This study demonstrated the social status influence on different individual caracteristics as song, personality or cognition in common domesticated canaries, Serinus canaria. Social rank associated with familiarity have an important influence on forraging strategies. This one is considered as personnality trait. Behavioral syndromes and photoperiods influence on repeatable personnality trait were suggested. Individual ontogeny as development acoustic condition has an impact on behavioral syndromes. These ones seem to be linked to the vocal production as song, and to the cognition as food research task learning. The social status influence the cognition in canaries. Nevertheless, no relation between different individual caracteristics and the heart rate has to be démonstrated.
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Pěstování vybraných energetických plodin výnosové parametry / Growing of energy crops - yield parametersNĚMEC, Václav January 2014 (has links)
Thesis deals with renewables resources, potential of biomass and plants phytomass. We focused on the cultivation of selected energy crops, as perennial grasses Elymus elongatus (subsp. ponticus, cv. Szarvasi-1), reed canary grass, miscanthus sinensis and annual crops of maize and sorghum. The practical part is aimed to the establishment of small plot trials with a variety Szarvasi-1, reed canary grass and miscanthus. We described the methods of field experiment establishing with crop Szarvasi-1 of their treatment and harvest. The results of our own experiments we compared with the literature data. The last part deals with the economy of growing selected crops.
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Dietas e promotores de crescimento para passeriformes cativos. / Diets and Growth Promoters for captive passarinesOliveira, Michel Reis 14 December 2011 (has links)
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Previous issue date: 2011-12-14 / In order to assess growth promoters for Passaricultura two sequenced experiments were proposed: the first to find the most appropriate diet for nutrition of different species, establishing five treatments: T1 - Mixture of Grains, T2 - Extruded Feed, T3 - Commercial mash, T4 - Test and mash and Test mash with added grainwith added grains, tested in vitro, to microbiological safety and chemical quality through multiple samplings and tests in triplicate and in vivo for the maintenance and productivity of birds. The second aimed to test the effects of major antimicrobial available today, establishing five other treatments: T1 Control, T2 - sulfamethoxazole and trimethoprim, T3 - Sulfaquinoxaline and neomycin, T4 - Tylosin tartrate and Clopidol, and T5 - Clopidol tested in vivo for maintenance, productivity and sanitization of poultry , provided orally , added to the dry diet (diet), using the doses recommended by the manufacturers. In vivo tests, we used 50 females of polygamous Oryzoborus maximilliani (Weevil) and Serinus canarius (Canary), in equivalent proportions in each experiment (total 100 animals) with ten repetitions to five treatments, ad libitum treated,
then settling in a completely randomized design (CRD ) for the first experiment and Randomized block design (RBD) for the second experiment. Tukey test at 5 % significance level for multiple comparisons being used by SISVAR ® program for all variables of both experiments. Given the results of the first experiment , it was concluded that the use of dry feed grains to test without captive passerines is the most suitable for maintaining optimal conformation of birds and provide quality and food safety. In the second experiment treatments 4 and 5 were similar and with better results (p<0.5) in the control of coccidiosis and mycoplasmosis of birds in the other treatments, however the tartrate Tylosin and Clopidol ( T4 ) by itself treat drug combination, uses a lower dose of the same, assuming best value . / Com o objetivo de avaliar promotores de crescimento para a Passaricultura foram propostos dois experimentos sequenciados: o primeiro para encontrar a ração mais adequada para nutrição de diversas espécies, estabelecendo cinco tratamentos: T1 Mistura de Grãos, T2 Ração Extrusada, T3 Farelada Comercial, T4 Farelada Teste e T5 Farelada Teste com adição de grãos, testados tanto in vitro, para a segurança microbiológica e qualidade bromatológica, através de múltiplas amostragens e provas em triplicatas, quanto in vivo para a manutenção e produtividade das aves. O segundo objetivou testar os efeitos dos principais antimicrobianos disponíveis atualmente no mercado, estabelecendo outros cinco tratamentos: T1 - Controle, T2 Sulfametoxazol e Trimetoprima, T3 Sulfaquinoxalina e Neomicina, T4 Tartarato de Tilosina e Clopidol; e T5 Clopidol, testados in vivo para a manutenção, produtividade e sanitização das aves, fornecidos por via oral, adicionados a dieta seca (ração), utilizando-se as doses preconizadas pelos fabricantes. Os testes in vivo, utilizaram 50 fêmeas polígamas de Oryzoborus maximilliani (Bicudo) e Serinus canarius (Canário), em proporções equivalentes, em cada experimento (totalizando 100 animais) com dez repetições para cinco tratamentos, tratadas ad libidum, estabelecendo-se então, um delineamento inteiramente casualizado (DIC), para o primeiro experimento e um Delineamento em Blocos Casualizado (DBC) para o segundo experimento, sendo utilizado o teste de Tuckey a 5% de significância para as comparações múltiplas através do programa SISVAR®, para todas as variáveis de ambos experimentos. Em vista dos resultados do primeiro experimento, concluiu-se que a utilização da ração farelada teste sem grãos para passeriformes cativos é o mais indicado, por manter a conformação ideal das aves e proporcionar qualidade e segurança alimentar. No segundo experimento os tratamentos 4 e 5, mostraram-se semelhantes e com melhores resultados (p<0,5) no controle da coccidiose e micoplasmoses dos pássaros em relação aos demais tratamentos, entretanto o Tartarato de Tilosina e Clopidol (T4) por se tratar de associação de fármacos, utiliza uma dose menor dos mesmos, pressupondo melhor custo benefício.
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Crossing the Atlantic Ocean to look elsewhere – a humanitarian crisis on the Canary Islands 2020-2021Ba Palmqvist, Penda January 2021 (has links)
During 2020 and 2021, a migration crisis has been developing on the Canary Islands in Spain. Large numbers of African migrants have made the dangerous journey from West Africa to the Canary Islands, risking their lives on the Atlantic Sea. Humanitarian aid organizations, like the Spanish Red Cross, are working intensively to handle the humanitarian needs of the migrants on land and on sea. The purpose of this thesis is to analyze why the migration crisis on the Canary Islands occurs. The migrants originate from different African countries with different reasons why they choose to migrate. In some countries, there are ongoing wars and conflicts, like in Mali. In other countries, people migrate because of poverty, climate change and displacement to seek a better life. This thesis will answer why Senegalese people choose to migrate on this dangerous route on the Atlantic Sea. The study is based on interviews with three Senegalese migrants and two representatives of humanitarian aid organizations. The analysis has been made from different migration theories. It shows that an important reason why the Senegalese migrants choose to migrate is that it is no longer possible to make a living by fishing and provide for their families. This works as an important push factor to migrate. Another push factor is the lack of trust in the Senegalese government. An important pull factor are the success stories from migrants who have made the journey through the Canary Islands. According to the aspiration and capabilities theory, the aspirations to migrate increase when a country goes from being very poor to richer. This is because the knowledge about the surrounding world and the opportunities increase. The study shows that migrants are well aware of the risks when crossing the Atlantic Sea, but they choose the route because there are almost no legal ways for them to migrate.
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Invasive Reed Canary Grass (Phalaris arundinacea) and Carbon Sequestration in a Wetland ComplexBills, Jonathan S. 16 January 2009 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Terrestrial carbon sequestration is one of several proposed strategies to reduce the rate of carbon dioxide (CO2) accumulation in the atmosphere, but the impact of plant invasion on soil organic carbon (SOC) storage is unclear. The results of past studies are often confounded by differences in vegetation and environmental conditions. Reed canary grass (Phalaris arundinacea) is an herbaceous species that invades riparian fringes and wetlands throughout North America, including Beanblossom Bottoms – a wetland complex in south-central Indiana. Because of the prolific growth of P. arundinacea, it was hypothesized that significant alterations in SOC pools and dynamics would occur at invaded sites within the wetland complex. To test this hypothesis, study plots were established in areas colonized either by native herbaceous species or by P. arundinacea. Above and below-ground biomass were collected at the middle and end of the growing season and were analyzed for cellulose, lignin, acid detergent fiber, total phenolics, and organic carbon and nitrogen concentration. Soil samples were analyzed for SOC and nitrogen, bulk density, pH, and texture. The biomass of Scirpus cyperinus – a native wetland species was found to contain significantly (P < 0.05) more lignin (168 g kg-1 versus 98 g kg-1) and phenolics (19 g kg-1 versus 3 g kg-1), and had a higher C to N ratio (28 versus 20) than P. arundinacea biomass, suggesting greater recalcitrance of S. cyperinus tissues compared to P. arundinacea biomass. Results of a laboratory incubation study were consistent with the residue biochemistry data and showed that S. cyperinus biomass degraded at much slower rates than the biomass of P. arundinacea. However, measurements of SOC pools (0-30 cm) showed larger pools under P. arundinacea (25.5 Mg C ha-1) than under stands of S. cyperinus (21.8 Mg C ha-1). Likewise, SOC stocks under stands of mixed native vegetation were significantly (P < 0.05) smaller (18.8 Mg C ha-1) than in areas invaded by P. arundinacea. Biomass of the mixed native vegetation was also considered more recalcitrant than that of P. arundinacea based on residue biochemistry. Therefore, contrary to the study hypothesis, residue quality was not a good predictor of SOC stocks in the wetland soils. Thus, it appears that traditional laboratory assessments of biomass recalcitrance and decomposition do not accurately simulate the various biological interactions occurring in the field.
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