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91	Estudo interdisciplinar em sedimentos lacustres da região sul do estado de São Paulo. Reconstrução da vegetação e do clima no Quaternário tardio / Interdisciplinary study of lacustrine sediments from Southeastern São Paulo state (Brazil). Late Quaternary vegetation and climate changes Passarini Junior, Jaime Rissi 28 August 2009 (has links) O estudo de um testemunho coletado às margens de uma lagoa situada em meio a vegetação de Mata Atlântica no Parque Estadual Turístico do Alto Ribeira, sul do estado de São Paulo, permitiu a reconstituição da história da vegetação local ao longo dos últimos 2500 anos. Para isso, foram realizadas análises elementares, isotópicas e palinológicas. Também a partir de material retirado deste testemunho procedeu-se a comparação entre dois protocolos de tratamento químico para análises palinológicas do Quaternário. Os protocolos utilizados seguiram as metodologias propostas por Faegri e Iversen, 1989 (Protocolo 2) e por Colinvaux et al., 1999 (Protocolo 1). Foi desenvolvido um método de comparação que envolveu a quantidade de palinomorfos e a quantidade de matéria orgânica amorfa encontrados em 450 pontos escolhidos aleatoriamente em lâminas de ambos os protocolos e também foram levados em consideração o tempo, a praticidade de aplicação em rotina laboratorial, os custos e as quantidades e tipos de resíduos para cada protocolo. Cinco amostras de sedimento foram utilizadas para comparação e o Protocolo 1 apresentou em média 10% menos matéria orgânica amorfa e quase três vezes mais palinomorfos que o Protocolo 2. Os resultados das análises isotópicas e da palinologia mostraram que a vegetação da área em estudo teve uma fisionomia florestal pelo menos desde os últimos 2550 anos. Os valores de \'delta\'13C, em torno de - 29%o, indicaram a presença de plantas C3 em todo o período estudado e registraram um enriquecimento isotópico (-24,9%o) entre aproximadamente 1650 e 1480 anos AP. A análise palinológica apontou para a ocorrência de um clima mais frio que o atual entre 2550 anos AP e 2000 anos AP, com aumento na freqüência de Araucaria e diminuição de Arecaceae. Também foi detectada a ocorrência de um período de clima mais quente e mais úmido entre aproximadamente 1000 anos AP e 680 anos AP, com desaparecimento de Araucaria e aumento de Arecaceae, Weinmannia e de pteridófitas. A maior umidade deste período também é apontada pelos valores de C/N que indicam aumento de influência terrestre no sedimento e pelo aumento de Botryococcus. Em todas as camadas foram encontradas partículas carbonizadas, indicando períodos de ocorrência de paleoincêndios e de abertura florestal provavelmente associados à presença humana na região / One sediment core collected at the margins of a lake surrounded by Atlantic rainforest vegetation at Parque Estadual do Alto Ribeira (PETAR), southern São Paulo state (Brazil), was analyzed, in order to reconstruct the history of the local vegetation over the last 2500 years. Elemental (Total Organic Carbon TOC and Total Organic Nitrogen), isotopic (C and N), pollen analysis and radiocarbon dating were integrated on this work. Also was made a comparison of two protocols for Quaternary pollen chemical treatment. The tested protocols were proposed by Faegri and Iversen, 1989 (Protocol 2) and by Colinvaux et al., 1999 (Protocol 1). The comparison methods developed in this study checked the protocols performance on the quantity of palinomorphs and of organic matter found in 450 random areas of microscope slides of each protocol. The time consuming, laboratory routine, costs and residue production by the protocols were considered for comparison. Five samples were used for comparison and the Protocol 1 showed an average of 10% less organic matter and more palinomorphs than Protocol 2. According to the isotopic and pollen results, the study area vegetation maintained as a forest for the last 2500 years BP. \'delta\'13C values of -29%o indicated the presence of C3 plants during all the sediment study and a isotopic enrichment (- 24,9%o) was observed between 1650 and 1480 yrs BP. Pollen analysis suggested the occurrence of colder climatic conditions between 2550 and 2000 yrs BP and a warmer and humid period was suggested between 1000 and 680 yrs BP. Charcoal particles were found since 2550 yrs BP indicating paleofire probably associated to the human activities Atlantic rainforest Carbon (C-12 C-13 C-14) and N isotopes Floresta Atlântica Late Quaternary Matéria orgânica sedimentar Palaeoenvironment Paleovegetação Pólen Pollen analysis protocol Quaternário tardio Sedimentary Organic Matter Stable isotopes (C N)
92	Des traits des graminées au fonctionnement de l'écosystème prairial : une approche de modélisation mécaniste Maire, Vincent 19 June 2009 (has links) (PDF) Dans un environnement fluctuant, le fonctionnement de l'écosystème prairial est régulé par la diversité des espèces végétales et leur dynamiqie propre. Comprendre les mécanismes fins par lesquels opère cette régulation et pouvoir simuler en retour le fonctionnement de l'écosystème sont des enjeux majeurs en agriculture (valorisation de la ressource fourragère) et en écologie ( gestion de la biodiversité). Dans ce cadre d'étude, nous avons développé, utilisé et évalué un modèle écophysiologique de diversité prairiale (GEMINI), qui simule de manière mécaniste la réponse des plantes à des contraintes climatiques et de gestion, et la dynamique des interactions entre les différentes espèces. Un dispositif expérimental situé à Theix a permis de paramétrer ce modèle grâce aux traits fonctionnels et de l'évaluer sur 13 espèces de graminées en culture pure et en mélange de six espèces, et sous deux conditions de fréquence de coupe et deux niveaux de fertilisation azotée. Nous avons montré que la complexité du modèle était nécessaire et suffisante pour prédire correctement la réponse individuelle de ces espèces dans ces différentes conditions. L'utilisation de ce modèle a également permis d'avancer les connaissances sur les différences de statégies végétales utilisées par les plantes pour les mécanismes d'acquisition et d'utilisation de l'azote minérale et d'acquisition du carbone atmosphérique pour la photosynthèse. Pour ces différents mécanismes nous avons montré des lois de compromis entre les différentes fonctions d'une plante et des lois de coordination entre les flux de carbone et d'azote au sein d'une plante. Grâce au modèle, nous avons montré que ces deux types de lois étaient essentiels pour le fonctionnement et la plasticité d'une plante. acquisition et utilisation de l'azote colimitation C :N écosystème prairial évaluation de modèle GEMINI graminées loi de compromis loi de coordination modélisation centrée sur l'individu paramétrage de modèle plasticité fonctionnelle photosynthèse foliaire stratégie végétale trait fonctionnel
93	Estudo interdisciplinar em sedimentos lacustres da região sul do estado de São Paulo. Reconstrução da vegetação e do clima no Quaternário tardio / Interdisciplinary study of lacustrine sediments from Southeastern São Paulo state (Brazil). Late Quaternary vegetation and climate changes Jaime Rissi Passarini Junior 28 August 2009 (has links) O estudo de um testemunho coletado às margens de uma lagoa situada em meio a vegetação de Mata Atlântica no Parque Estadual Turístico do Alto Ribeira, sul do estado de São Paulo, permitiu a reconstituição da história da vegetação local ao longo dos últimos 2500 anos. Para isso, foram realizadas análises elementares, isotópicas e palinológicas. Também a partir de material retirado deste testemunho procedeu-se a comparação entre dois protocolos de tratamento químico para análises palinológicas do Quaternário. Os protocolos utilizados seguiram as metodologias propostas por Faegri e Iversen, 1989 (Protocolo 2) e por Colinvaux et al., 1999 (Protocolo 1). Foi desenvolvido um método de comparação que envolveu a quantidade de palinomorfos e a quantidade de matéria orgânica amorfa encontrados em 450 pontos escolhidos aleatoriamente em lâminas de ambos os protocolos e também foram levados em consideração o tempo, a praticidade de aplicação em rotina laboratorial, os custos e as quantidades e tipos de resíduos para cada protocolo. Cinco amostras de sedimento foram utilizadas para comparação e o Protocolo 1 apresentou em média 10% menos matéria orgânica amorfa e quase três vezes mais palinomorfos que o Protocolo 2. Os resultados das análises isotópicas e da palinologia mostraram que a vegetação da área em estudo teve uma fisionomia florestal pelo menos desde os últimos 2550 anos. Os valores de \'delta\'13C, em torno de - 29%o, indicaram a presença de plantas C3 em todo o período estudado e registraram um enriquecimento isotópico (-24,9%o) entre aproximadamente 1650 e 1480 anos AP. A análise palinológica apontou para a ocorrência de um clima mais frio que o atual entre 2550 anos AP e 2000 anos AP, com aumento na freqüência de Araucaria e diminuição de Arecaceae. Também foi detectada a ocorrência de um período de clima mais quente e mais úmido entre aproximadamente 1000 anos AP e 680 anos AP, com desaparecimento de Araucaria e aumento de Arecaceae, Weinmannia e de pteridófitas. A maior umidade deste período também é apontada pelos valores de C/N que indicam aumento de influência terrestre no sedimento e pelo aumento de Botryococcus. Em todas as camadas foram encontradas partículas carbonizadas, indicando períodos de ocorrência de paleoincêndios e de abertura florestal provavelmente associados à presença humana na região / One sediment core collected at the margins of a lake surrounded by Atlantic rainforest vegetation at Parque Estadual do Alto Ribeira (PETAR), southern São Paulo state (Brazil), was analyzed, in order to reconstruct the history of the local vegetation over the last 2500 years. Elemental (Total Organic Carbon TOC and Total Organic Nitrogen), isotopic (C and N), pollen analysis and radiocarbon dating were integrated on this work. Also was made a comparison of two protocols for Quaternary pollen chemical treatment. The tested protocols were proposed by Faegri and Iversen, 1989 (Protocol 2) and by Colinvaux et al., 1999 (Protocol 1). The comparison methods developed in this study checked the protocols performance on the quantity of palinomorphs and of organic matter found in 450 random areas of microscope slides of each protocol. The time consuming, laboratory routine, costs and residue production by the protocols were considered for comparison. Five samples were used for comparison and the Protocol 1 showed an average of 10% less organic matter and more palinomorphs than Protocol 2. According to the isotopic and pollen results, the study area vegetation maintained as a forest for the last 2500 years BP. \'delta\'13C values of -29%o indicated the presence of C3 plants during all the sediment study and a isotopic enrichment (- 24,9%o) was observed between 1650 and 1480 yrs BP. Pollen analysis suggested the occurrence of colder climatic conditions between 2550 and 2000 yrs BP and a warmer and humid period was suggested between 1000 and 680 yrs BP. Charcoal particles were found since 2550 yrs BP indicating paleofire probably associated to the human activities Floresta Atlântica Matéria orgânica sedimentar Paleovegetação Pólen Quaternário tardio Atlantic rainforest Carbon (C-12 C-13 C-14) and N isotopes Late Quaternary Palaeoenvironment Pollen analysis protocol Sedimentary Organic Matter Stable isotopes (C N)
94	The Development of Marine Aquaponics Yu-Ting Chu (11777624) 01 December 2021 (has links) Integrated aquaponic food production systems are capable of producing more food on less land using less water than conventional food systems, and marine systems offer the potential of conserving freshwater resources. However, critical factors such as suitable species combinations, environmental conditions (salinity and pH), and nutrient management (animal to plant ratio, C/N ratio, and dietary crude protein) have not been fully understood for marine systems. There were four objectives in this project. The first objective was to evaluate the growth performance of potential comparable combination (whiteleg shrimp with three halophytic plants) for the development of marine aquaponics with BFT under different salinities. The second objective was to evaluate stocking densities and the C/N ratio on growth and production of whiteleg shrimp and three halophytes. The third objective was evaluation of varying concentrations of dietary crude protein in practical diets fed to shrimp raised in biofloc aquaponic saltwater systems. The fourth objective was to evaluate effects of pH levels and additional C on the growth and production of whiteleg shrimp and five plant species in marine aquaponics. Four conclusions were determined: 1) Regarding marine aquaponics, whiteleg shrimp and the three halophytes (Atriplex hortensis, Salsola komarovii, and Plantago coronopus) are suitable combinations for future development. According to the research results, shrimp performed better in a salinity of 15 and 20 ppt; yet, plants performed better in a salinity of 10 and 15 ppt. Therefore, a salinity of 15 ppt is suggested as the optimal saline condition for shrimp and the three halophytes in an indoor marine aquaponics system. In addition, inoculating probiotics do have the efficiency of stabilizing water quality, cultivating microbial community, and enhancing the health of shrimp and plants in the operation of aquaponics. 2) The stocking density ratio and C/N ratio exerted significant impacts on the performance of shrimp and plants in marine aquaponics. Shrimp performed better with the stocking density of 2:1 and 3:1, with no impact from the C/N ratio. Conversely, plants performed better with the stocking density of 3:1 and 5:1 with the C/N ratio at 15. Therefore, a stocking density ratio of 3:1 with a C/N ratio at 15 is suggested as the optimal condition for shrimp and the three halophytes in an indoor marine aquaponic food production system. Inoculating the water with biofloc and applying probiotics regularly can enhance the management of water quality and the health of shrimp and plants in aquaponics. 3) Among the findings of the study, shrimp growth was not affected by the protein content of the feed, suggesting that it is possible to use feeds with lower protein concentration when culturing shrimp in biofloc-based marine aquaponics. However, plants grew better in the treatments with higher protein content feed in the early and middle stages of production. Hence, for maximum production, providing a higher protein concentration feed (35 %) in the early stages of system start-up, and switching to a lower protein concentration feed (30 %) in the later stages of cultivation might be feasible. 4) The current study found no significant effects of pH or additional C on shrimp performance. In contrast, plants grew better in lower pH treatments, while additional C supplements improved the performance of plants grown in higher pH treatments and had similar results to the lower pH treatments. We suggest that RO water is not suitable source of water for shrimp-based marine aquaponics if ionic composition is not managed. The addition of C, however, led to improved growth and yields of most plants. Hence, adding C can be a promising approach in marine aquaponics to enhance the resistance to the abiotic stress of plants and improve their growth.<div> <br>The present study on marine aquaponics has produced important findings that will fill some knowledge gaps, provide management guidelines for production, and facilitate its development. <br></div> Sustainable Agricultural Development Aquaculture Fisheries Management Marine aquaponics Biofloc system Litopenaeus vannamei Halophytes Probiotics Water-pump-less system design Sustainable food production Shrimp to plant ratio C/N ratio Crude protein concentration pH conundrum
95	Absorción de nitrato en cultivo sin suelo. Estudio de las implicaciones agronómicas y fisiológicas como base para optimizar el manejo de la fertilización. Aplicación a un cultivo de rosas Roca Ferrerfábrega, María Dolores 25 November 2009 (has links) La integración de la técnica de cultivo sin suelo en el sistema invernadero permite optimizar tanto el ambiente de las raíces - responsables de los procesos de absorción de agua y elementos minerales disueltos en ella -, como los ajustes de sus aportes en función de la demanda de la planta a escala de minutos. En tiempos cortos, las demandas hídricas y de minerales (N-NO3-) son asincrónicas. Las tasas de absorción son variales, y los factores que le afectan son múltiples. La obtención de modelos de estimación de la demanda mineral (NO3) a escala horaria en función de parámetros fácilmente medibles en los sistemas de producción invernadero-CSS - como los climáticos - o estimables - como la demanda hídrica, es uno de los objetivos principales de este estudio, el cual se realiza sobre un cultivo-modelo, el rosal para flor cortada de producción continua, bajo condiciones comerciales de producción, las cuales han adoptado el cultivo sin suelo recirculante cuya mejora merece ser atendida. La absorción mineral depende de la energía procedente de la oxidación de los asimilados en las raíces que son traslocados desde la parte aérea fotosintética. Se ha considerado el manejo de la parte aérea adoptado por el cultivador, en el que se distinguen dos compartimientos, uno creado mediante el arqueado de tallos no comerciales, cuya función es la generación permanente de asimilados, y otro que son los tallos florales que cuando alcanzan su estado de madurez fotosintética, son recolectados. Se producen variaciones estacionales de las relaciones fuente/sumidero y de las fuerzas de sumidero entre la cosecha y las raíces, que afectan a la absorción mineral. / Roca Ferrerfábrega, MD. (2009). Absorción de nitrato en cultivo sin suelo. Estudio de las implicaciones agronómicas y fisiológicas como base para optimizar el manejo de la fertilización. Aplicación a un cultivo de rosas [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/6474 C/n Repartos Prácticas de manejo del cultivo Flor cortada Fertilización Cultivo sin suelo Absorción de nitrato Optimización Área foliar específica Demanda de la planta Temperatura Fuente/sumidero Radiación interceptada Modelos Rosa x hybrida BIOLOGIA VEGETAL FISIOLOGIA VEGETAL 310702 - Técnicas de cultivo 3107 - Horticultura 310703 - Floricultura 3103 - Agronomía
96	Frauen schreiben Krieg Pape, Marion 02 February 2007 (has links) Kein anderes Thema hat die nigerianische Literatur so dominiert wie der nigerianische Bürgerkrieg, in dessen Verarbeitung sich verstärkt auch Autorinnen einmischen. Die Dissertation evaluiert 34 Texte von 16 nigerianischen Autorinnen - 12 Romane und 22 Kurzgeschichten - und analysiert sie als Gesamtkorpus, in dem die Texte miteinander und mit der Männerliteratur einen Dialog um den Bürgerkrieg führen. Die Autorinnen wenden bei ihrem "war talk" literarische Strategien wie "re-reading" und "re-writing" an, das Neu-Lesen, Fort- und Umschreiben der Texte und Diskurse des "Zentrums", durch die nicht nur die Blindstellen eines von Männern dominierten literarischen Diskurses sichtbar werden, sondern durch die auch der Prozess des Aushandelns der Geschlechterverhältnisse sowie des Krieges selbst erfolgt, seiner Ursachen, Auslöser und Folgen. Die Autorinnen stellen den Krieg als "sexuelle Unordnung" dar, als Geschlechterkrieg. Die Untersuchung zeigt, dass bei der Verortung der Perspektive der Autorinnen neben Geschlecht, ethnischer Zugehörigkeit auch andere Faktoren, wie Alter, Race, Grad der Distanz oder Nähe etc. berücksichtigt werden müssen, um vorschnelle Festschreibungen zu vermeiden. Hierbei spielen die Paratexte eine wichtige Rolle, in denen die Autorinnen sich persönlich zum Krieg äußern. Die Arbeit bewegt sich an den Schnittstellen mehrerer Disziplinen: Literatur, Historiographie und Geschlechterstudien. In der Einleitung werden die theoretischen Prämissen im Kontext von Krieg, Geschlecht und literarischer Repäsentation behandelt. Das 1. Kapitel ist dem historischen Kontext des Bürgerkrieges, einschließlich der Rolle der Frauen darin gewidmet. Im 2. Kapitel geht es um die Darstellung des Krieges, des Selbst- und Feindbildes sowie der Zukunft. Das dritte Kapitel handelt von der Beziehung zwischen Bürger- und Geschlechterkrieg, vermittelt durch das Medium literarischer Text. Die Zusammenfassung der Ergebnisse und der Ausblick auf zukünftige Forschung erfolgt im Schlussteil. Der Anhang enthält ein vorläufiges Verzeichnis der gesamten Frauenliteratur über den nigerianischen Bürgerkrieg. / No other topic has dominated the Nigerian literature as much as the Nigerian Civil War and female authors increasingly interfere in its literary representation. The thesis evaluates 34 literary texts by 16 female Nigerian authors - 12 novels and 22 short stories - and analyses them as distinctive corpus whose individual texts are in a state of dialogue both with each other and with texts from male authors. The female authors use, in their "war talk", literary strategies like "re-reading" and "re-writing" of texts from the "Centre". On the one hand, these strategies enable them to make the blind spots of a male dominated literary discourse apparent/visible on the other hand, they facilitate the negotiation of gender relations and of the war itself, its causes, trigger points and consequences. The female authors represent war as "sexual disorder", as gender war. The study shows that in order to be able to locate an author''s perspective (and to avoid rash conclusions) it is essential to consider the different factors determining it - besides ethnicity and gender, also age, race, the grade of emotional involvement or distance etc. It is in this regard, where the paratexts play an important part, as in these authors express their personal views and comments on the war. The thesis is located at the interfaces of several disciplines: literary, historical and gender studies. The introduction deals with the theoretical backgrounds in the context of war, literary representation and gender. The first chapter is dedicated to the historical context of the Nigerian Civil War including the role of women. The second chapter looks at the paratexts, different representations of the war''s causes, the self-image, the enemy''s image and the future. The third chapter finally deals with the question how the relationship between Civil War and gender war is negotiated/conveyed through the medium of the literary texts. In the conclusion the results are summarized and prospects for future research are discussed. The appendix contains a preliminary bibliography of all literary texts on the Nigerian Civil War written by female authors. Krieg Geschlechterverhältnisse literarische Repräsentation nigerianischer Bürgerkrieg Geschlechterkrieg afrikanische Literatur Nigeria Biafra Igbo-Autorinnen Flora Nwapa C. N. Adichie Frauenkrieg A. Adimora-Ezeigbo Phanuel Egejuru Mabel Segun Eno Obong Anne Giwa-Amu Chinua Achebe Cyprian Ekwensi Paratexte Intertextualität Vergewaltigung Körper neue Frau Heldenbild Schuld Verantwortung Versöhnung Heimatfront sexuelle Unordnung Bipolarität C. O. Ogunyemi war gender war literary representation Nigerian civil war African literature Nigeria Biafra Igbo-authors Flora Nwapa C. N. Adichie Women''s war paratexts intertextuality A. Adimora-Ezeigbo Phanuel Egejuru Mabel Segun Eno Obong Anne Giwa-Amu Chinua Achebe Cyprian Ekwensi rape body Mammywater new woman hero healing reconciliation cross-dressing C. O. Ogunyemi wo/man palava MK 3100 MS 2850 ddc:800
97	Auswirkungen von Ökosystemmanipulationen auf Vorratsänderung und Freisetzung von C- und N- Verbindungen / Effects of ecosystem manipulations on stock change and flux of N- and C-compounds in soil Horváth, Balázs 28 July 2006 (has links) No description available. 500 Naturwissenschaften Forest Sciences and Forest Ecology 15N Markierung atmosphärische Stickstoff-Eintrag Boden C Boden Respiration Boden-Substrat Kontaktfläche C:N Verhältnisse Kohlenstoff Speicherung Kompostausbringung im Wald mikrobiologische Biomasse Mineralisation Nah Infrarot Spektroskopie Nitrat Versickerung N-Sättigung 15N tracing C sequestration C/N ratio carbonate content compost application microbial biomass mineralization N-deposition near infrared spectroscopy nitrate leaching nitrification N-saturation soil carbon soil respiration soil substrate contact area 48.32 Bodenkunde Bodenbewertung

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