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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Diversidade morfológica de Collembola em sistemas de uso do solo no leste de Santa Catarina / Collembola morphological diversity in land-use systems in the Eastern region of Santa Catarina

Santos, Marcielli Aparecida Borges dos 23 February 2017 (has links)
Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-03-08T14:49:04Z No. of bitstreams: 1 PGCS17MA163.pdf: 2398294 bytes, checksum: 7b3bc412b8dffb1fe76e721e42fd8595 (MD5) / Made available in DSpace on 2018-03-08T14:49:04Z (GMT). No. of bitstreams: 1 PGCS17MA163.pdf: 2398294 bytes, checksum: 7b3bc412b8dffb1fe76e721e42fd8595 (MD5) Previous issue date: 2017-02-23 / Capes / The springtails (Collembola) are edaphic organisms with enormous morphological diversity and are affected by physical, chemical and biological soil properties. The aim of this study was to evaluate if the land-use influences the morphological diversity of springtails and to relate with the occurrence of these physical, chemical and microbiological soil attributes. Samples were collected in the eastern region of Santa Catarina, Brazil, involving three municipalities: Joinville, Blumenau and Timbó in the land-use systems (LUS) of native forest (NF), Eucalyptus plantation (EP), pasture (PA), integrated crop-livestock (ICL) and no-tillage crops (NT). The soil samples for determination of the edaphic attributes and the installation of Pitfall traps were carried in winter and summer, in the same points, from a sample grid of 3×3 points. The springtails captured were counted and morphotyped, observing characteristics such as: presence or absence of ocelli and fur, pigmentation, antenna length and furcula. For each one of these characteristics a score was assigned and by summing these values the morphotype and its adaptation to the soil were defined. The data were analyzed using abundance, Shannon-Wiener diversity index (H'), Pielou uniformity index (J), morphotypes richness and Margalef index, and modified Soil Biological Quality Index (QBS). Abundance was submitted to principal component analysis (PCA) to verify the relationship between morphotypes and LUS, using edaphic attributes as explicative environmental variables. The richness of springtails morphotypes was higher in NF and ICL, while the abundance was higher in ICL and PA in winter. The H' e Margalef indexes were higher in winter in the LUS where the intensity of use is lower (NF). In the summer, only H' differed significantly between LUS and was higher in NF. In all systems, the QBS index was higher in the summer season, with the exception of PA. The PCA showed a distinction between the seasons and the LUS, in which the occurrence of morphotypes was more related to microbiological attributes in the winter: microbial biomass carbon, microbial respiration and metabolic quotient; and chemical: potential acidity, organic matter and magnesium/potassium ratio. While in the summer, the morphotypes were explained by physical attributes: total porosity, biopores, soil moisture and macroporosity; and soil chemistry: organic matter and carbon/nitrogen ratio. The morphological diversity of springtails was influenced by conditions found in each LUS, showing sensitivity to changes in land-use, and thus can be considered a good tool for evaluation the biological quality of soil / Os colêmbolos (Collembola) são organismos edáficos com enorme diversidade morfológica e são influenciados pelas propriedades físicas, químicas e biológicas do solo. O objetivo deste estudo foi avaliar se o uso do solo influencia na diversidade morfológica de colêmbolos e relacionar a ocorrência destes com atributos físicos, químicos e microbiológicos do solo. Foram coletadas amostras na região do Leste Catarinense, envolvendo três municípios: Joinville, Blumenau e Timbó nos sistemas de usos do solo (SUS) de floresta nativa (FN), reflorestamento de eucalipto (RE), pastagem perene (PA), integração lavoura-pecuária (ILP) e plantio direto (PD). As coletas de solo para determinação dos atributos edáficos e a instalação de armadilhas de solo (Pitfall traps) foram realizadas no inverno e verão, nos mesmos pontos, em grade amostral de 3×3 pontos. Os colêmbolos capturados foram contados e morfotipados, observando características como: presença ou ausência de ocelos e pelos, pigmentação, comprimento de antenas e tamanho de fúrcula. Para cada uma destas características se atribuiu uma pontuação e por meio da soma desses valores definiu-se o morfotipo e a sua adaptação ao solo. Os dados foram analisados por meio da abundância, diversidade de Shannon-Wiener (H’), uniformidade de Pielou (J), riqueza de morfotipos e de Margalef, e Índice de Qualidade Biológica do Solo (QBS) modificado. A abundância foi submetida à análise de componentes principais (ACP) para verificar a relação entre os morfotipos e os SUS, usando os atributos edáficos como variáveis ambientais explicativas. A riqueza de morfotipos de colêmbolos foi mais elevada em FN e ILP, enquanto a abundância de colêmbolos foi maior em ILP e PA, no inverno. Os índices H’ e Margalef foram maiores no inverno no SUS em que a intensidade de uso é menor (FN). No verão, somente H’ diferiu significativamente entre os SUS e foi maior em FN. Em todos os SUS estudados o índice QBS foi mais elevado na época do verão, com exceção da PA. A ACP mostrou distinção entre as épocas e os SUS. No inverno a ocorrência de morfotipos esteve mais relacionada aos atributos microbiológicos: carbono da biomassa microbiana, respiração microbiana e quociente metabólico; e químicos: acidez potencial, matéria orgânica e relação magnésio/potássio. Enquanto no verão, a ocorrência dos morfotipos foi mais explicada pelos atributos físicos: porosidade total, bioporos, umidade e macroporosidade; e químicos do solo: matéria orgânica e relação carbono/nitrogênio. A diversidade morfológica de colêmbolos foi influenciada pelas condições encontradas em cada SUS, mostrando sensibilidade às alterações no uso do solo, e desta forma, pode ser considerada uma boa ferramenta para avaliação da qualidade biológica do solo
2

Atributos químicos, físicos e biológicos de um Neossolo Quartzarênico sob sistemas agroflorestais biodiversos / Chemical, physical and biological attributes of a Neossolo Quartzarênico under biodiversal agroflorestatic systems

Leite, Dryela Ribeiro 11 September 2017 (has links)
Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2017-11-30T12:41:43Z No. of bitstreams: 2 Dissertação - Dryela Ribeiro Leite - 2017.pdf: 1923476 bytes, checksum: 119a7b686f9594584f016a595e9bae6b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-11-30T13:00:22Z (GMT) No. of bitstreams: 2 Dissertação - Dryela Ribeiro Leite - 2017.pdf: 1923476 bytes, checksum: 119a7b686f9594584f016a595e9bae6b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-11-30T13:00:22Z (GMT). No. of bitstreams: 2 Dissertação - Dryela Ribeiro Leite - 2017.pdf: 1923476 bytes, checksum: 119a7b686f9594584f016a595e9bae6b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-09-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The sustainability of the productive capacity of a soil is due to the type of land use and management system, which makes it necessary to adopt practices and technologies that aim at the continuity of the exploitation of its resources in a rational and long term way. The objective of this work was to evaluate the soil attributes of a Neossolo Quartzarênico and its ability to sequester carbon under biodiverse systems for two consecutive years. Chemical, physical and biological attributes and carbon sequestration capacity of six different soil use systems were evaluated: four Agroforestry Systems, a consolidated no - tillage system and a native forest area in good conservation status. Soil samples were collected at depths of 0-5 cm, 5-15 cm, 15-30 cm and 30-50 cm for the chemical, physical and carbon analyzes in the soil and at depth of 0-10 cm for the microbiological analyzes. Data were submitted to analysis of variance and the Scott-Knott 5% mean test, and as a complementary analysis we used the multivariate canonical analysis technique and the Tocher grouping method. The SAF4 system was the system that presented the most promising as the characteristics evaluated. The management of this system favored soil fertility even though it was extremely sandy and did not compromise soil structure, provided greater efficiency of microbial biomass, increased nutrient cycling, organic matter production, humification and carbon storage capacity. the system that presented the best results for the physical characteristics of the soil evaluated. / A sustentabilidade da capacidade produtiva de um solo é decorrente do tipo de sistema de uso e manejo da terra, o que torna necessário a adoção de práticas e tecnologias que visem a continuidade da exploração de seus recursos de maneira racional e a longo prazo. Este trabalho objetivou avaliar os atributos do solo de um Neossolo quartzarênico e sua capacidade de sequestrar carbono sob sistemas biodiversos por dois anos consecutivos. Foram avaliados atributos químicos, físicos, biológicos e a capacidade de sequestro de carbono de seis diferentes sistemas de uso do solo: quatro Sistemas Agroflorestais, um sistema de plantio direto consolidado e uma área de floresta nativa em bom estado de conservação. As amostras de solo foram coletadas nas profundidades de 0-5 cm, 5-15 cm, 15-30 cm e 30-50cm para as análises química, física e carbono no solo e na profundidade de 0-10cm para as análises microbiológicas. Os dados foram submetidos à análise de variância e ao teste de média Scott-Knott a 5%, e como análise complementar foi utilizada a técnica multivariada de análise canônica e o método de agrupamento de Tocher. O SAF4 foi o sistema que se apresentou mais promissor quanto as características avaliadas. O manejo desse sistema favoreceu a fertilidade do solo mesmo esse sendo extremamente arenoso e não comprometeu a estrutura do solo, proporcionou uma maior eficiência da biomassa microbiana, maior ciclagem de nutrientes, produção de matéria orgânica, humificação e capacidade de estocagem de carbono, sendo ainda o sistema que apresentou os melhores resultados para as características físicas do solo avaliadas.
3

Ny tid över tegarna : Nyodling och skifte i Torstuna härad 1750-1914

Lundqvist, Maja January 2017 (has links)
The purpose of this thesis is to elucidate the importance of the enclosure movement for the agricultural development in the area of Mälardalen, Sweden. This is done through a case study of Torstuna härad between the years 1750-1914 by sampling five points in time. By studying the long term development of land reclamation and its correlation with meadow acreage, crop rotation and animal stock the thesis argues that the the radical enclosures in the 1850’s was a course of action to regain opportunities for agricultural expansion. The most intense period of land reclamation was after the implementation of radical enclosure which brought with it a change from communal land use to private ownership. Private property rights meant a new set of advantages for the individual farmer to plan and invest and balance the arable and the meadow.
4

Systems assessment of biofuels: Modelling of future cost and greenhouse gas abatement competitiveness between biofuels for transport on the case of Germany

Millinger, Markus 20 February 2019 (has links)
Biofuels are a renewable alternative for reducing the climate impact of transport. Due to the versatility of biomass and complexity of economics and impacts, biofuels are part of a complex system, which is here analysed from a systems perspective. Several models are developed in order to assess the competitiveness of various crop based biofuel options as part of a system, using different economic and environmental functional units. The scope is set to Germany until 2050. The capital and feedstock costs were revised to higher levels compared to common assumptions. The different functional units result in different merit orders for the biofuel options. Currently used biofuels, rape seed based biodiesel and starch crop based bioethanol, were found not to be competitive when considering differentiated and increasing feedstock costs. Advanced liquid fuels were only competitive at extreme assumptions, contrary to common expectations. Instead, sugar beet based ethanol dominated for most of the time span when comparing energetic cost, whereas Synthetic Natural Gas (SNG) was competitive on a greenhouse gas abatement (GHG) cost basis, especially at a rapid decarbonisation of the power mix. With a land use GHG abatement functional unit, silage maize based biomethane was the best, with SNG converging only at very high renewables shares of the background systems. Switching from current practise to higher yielding biofuel options can treble the abatement per land area for the present day, and potentially increase it by a factor five in the future. A focus on GHG abatement per area of arable land results in the land passenger transport sector to be of the highest priority due to the suitability of higher yielding biofuel options, followed by land goods transport, shipping and finally aviation. If gaseous fuels are not possible to introduce on a large scale, sectors where liquefied gaseous fuels are suitable become the priority, i.e. goods transport and shipping. The current practise of applying admixture quotas to sub-sectors of land transport renders a significantly lower climate benefit compared to an overall optimal usage, and a large societal transition is required before aviation biofuels become the climate optimal biomass usage. The direct importance of land use has thus far not received enough attention in terms of the economics of biofuels from dedicated crops, as well as for the greenhouse gas emissions policy. Biofuels produced from arable land can provide a strong GHG benefit if an expansion of arable land is hindered through redirecting land use, which requires a holistic policy approach.:Abstract ix Acknowledgments xi List of Publications xiii List of Acronyms xv I Introductory chapters 1 1 Background 3 1.1 Biofuels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2 Technological Change and Modelling . . . . . . . . . . . . . . . . . . . . . . 6 1.3 Aim and objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2 Methodology 9 2.1 Systems modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.2 Model description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3 Results and discussion 17 3.1 Biofuel techno-economic potential and competitiveness . . . . . . . . . . . . 17 3.2 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.2.1 Resource base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.2.2 Biomass climate benefit in other sectors . . . . . . . . . . . . . . . . 20 3.2.3 Other renewable fuel options . . . . . . . . . . . . . . . . . . . . . . 21 3.2.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.2.5 Applicability of results to other regions . . . . . . . . . . . . . . . . 22 4 Conclusions 25 4.1 Future research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Bibliography 29 Contribution to Appended Papers 33 Curriculum Vitae 35 CONTENTS II Appended papers 37 1 Competitiveness of advanced and conventional biofuels: Results from least-cost modelling of biofuel competition in Germany 39 2 Biomass price developments inhibit biofuel investments and research in Germany: The crucial future role of high yields 51 3 Relative greenhouse gas abatement cost competitiveness of biofuels in Germany 63 4 Climate optimal deployment of biofuels from crops in Germany 85 / Biokraftstoffe sind eine erneuerbare Alternative zur Verringerung der Klimaauswirkungen des Verkehrs. Aufgrund der Vielseitigkeit der Biomasse und der Komplexität der Ökonomie und der Auswirkungen sind Biokraftstoffe Teil eines komplexen Systems, das hier aus einer Systemperspektive analysiert wird. Es werden mehrere Modelle entwickelt, um die Wettbewerbsfähigkeit verschiedener biogener Biokraftstoffoptionen als Teil eines Systems unter Verwendung verschiedener wirtschaftlicher und ökologischer Funktionseinheiten zu bewerten. Der Umfang ist auf Deutschland bis 2050 festgelegt. Die Kapital- und Rohstoffkosten wurden im Vergleich zu herkömmlichen Annahmen auf ein höheres Niveau angepasst. Die verschiedenen Funktionseinheiten führen zu unterschiedlichen Merit Order für die Biokraftstoffoptionen. Die derzeit verwendeten Biokraftstoffe, Raps-Saatgut-Biodiesel und Stärkepflanzen-Bioethanol, erwiesen sich als nicht wettbewerbsfähig, wenn man differenzierte und steigende Rohstoffkosten in Betracht zieht. Fortschrittliche flüssige Kraftstoffe waren nur unter extremen Annahmen wettbewerbsfähig, entgegen den üblichen Erwartungen. Stattdessen dominierte Ethanol auf Zuckerrübenbasis für einen Großteil der Zeitspanne beim Vergleich der Energiekosten, während synthetisches Erdgas (SNG) auf der Basis der Treibhausgasvermeidungskosten wettbewerbsfähig war, insbesondere bei einer schnellen Dekarbonisierung des Strommixes. Mit einer Funktionseinheit zur Reduzierung der Treibhausgasemissionen war Silagemais-basiertes Biomethan die beste Option, wobei SNG bei sehr hohen Anteilen an erneuerbaren Energien der Hintergrundsysteme konvergierte. Der Wechsel von der derzeitigen Praxis zu ertragreicheren Biokraftstoffoptionen kann die Verringerung pro Landfläche für die Gegenwart verdreifachen und in Zukunft möglicherweise um den Faktor fünf erhöhen. Die Fokussierung auf die Reduzierung von Treibhausgasen pro Ackerfläche führt dazu, dass der Landpersonenverkehr aufgrund der Eignung ertragreicherer Biokraftstoffoptionen, gefolgt von Landverkehr, Schifffahrt und schließlich Luftfahrt, höchste Priorität genießt. Wenn es nicht möglich ist, gasförmige Kraftstoffe in großem Maßstab einzuführen, werden Sektoren, in denen verflüssigte gasförmige Kraftstoffe geeignet sind, zur Priorität, d.h. Güterverkehr und Schifffahrt. Die aktuelle Praxis der Anwendung von Beimischungsquoten für Teilbereiche des Landverkehrs führt zu einem deutlich geringeren Klimanutzen im Vergleich zu einer insgesamt optimalen Nutzung, und es ist ein großer gesellschaftlicher Wandel erforderlich, bevor Biokraftstoffe aus der Luftfahrt zur klimaoptimalen Biomassenutzung werden. Die direkte Bedeutung der Landnutzung hat bisher nicht genügend Beachtung gefunden, sowohl in Bezug auf die Wirtschaftlichkeit von Biokraftstoffen aus Sonderkulturen als auch in Bezug auf die Treibhausgasemissionen. Biokraftstoffe, die von Anbaubiomasse hergestellt werden, können einen starken Treibhausgasvorteil bieten, wenn eine Ausweitung der Ackerfläche durch eine Neuausrichtung der Landnutzung behindert wird, was einen ganzheitlichen politischen Ansatz erfordert.:Abstract ix Acknowledgments xi List of Publications xiii List of Acronyms xv I Introductory chapters 1 1 Background 3 1.1 Biofuels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2 Technological Change and Modelling . . . . . . . . . . . . . . . . . . . . . . 6 1.3 Aim and objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2 Methodology 9 2.1 Systems modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.2 Model description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3 Results and discussion 17 3.1 Biofuel techno-economic potential and competitiveness . . . . . . . . . . . . 17 3.2 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.2.1 Resource base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.2.2 Biomass climate benefit in other sectors . . . . . . . . . . . . . . . . 20 3.2.3 Other renewable fuel options . . . . . . . . . . . . . . . . . . . . . . 21 3.2.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.2.5 Applicability of results to other regions . . . . . . . . . . . . . . . . 22 4 Conclusions 25 4.1 Future research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Bibliography 29 Contribution to Appended Papers 33 Curriculum Vitae 35 CONTENTS II Appended papers 37 1 Competitiveness of advanced and conventional biofuels: Results from least-cost modelling of biofuel competition in Germany 39 2 Biomass price developments inhibit biofuel investments and research in Germany: The crucial future role of high yields 51 3 Relative greenhouse gas abatement cost competitiveness of biofuels in Germany 63 4 Climate optimal deployment of biofuels from crops in Germany 85
5

Nutrient dynamics and their control in land use systems of forest margins in Central Sulawesi, Indonesia / Die Nährstoffdynamik und ihre Steuerung in Landnutzungssystemen der Waldrandgebiete Zentralsulawesis in Indonesien

Dechert, Georg 06 November 2003 (has links)
No description available.
6

Argumente und Möglichkeiten für eine Quantifizierung und ein Monitoring der differenzierten Landnutzung

Walz, Ulrich, Jaeger, Jochen A.G., Haber, Wolfgang 04 May 2023 (has links)
The concept of differentiated land use was formulated already 50 years ago to preserve biodiversity and to maintain or restore the necessary landscape structure. Although it has been anchored in the Federal Nature Conservation Act, there is still no monitoring of its implementation, although the German Advisory Council on the Environment has been calling for this for 25 years. The paper argues that the technical prerequisites for monitoring the differentiated land use are ready today and discusses the conceptual steps necessary. It identifies several dimensions and proposes corresponding indicators of landscape structure, in particular the degree of diversification and the mixing of intensive land uses, the distribution of the size of intensively used areas, the proportion of semi-natural areas (at least 10 %) and the interconnected arrangement of semi-natural areas. Furthermore, the paper discusses suitable reference units and existing data. Finally, we identify remaining gaps in the data basis and discuss the question of defining target values. / Das Konzept der differenzierten Landnutzung wurde bereits vor 50 Jahren formuliert, um Biodiversität zu erhalten und die dazu erforderliche Landschaftsstruktur zu bewahren oder wiederherzustellen. Es ist zwar im Bundesnaturschutzgesetz verankert worden, aber es fehlt noch immer ein Monitoring seiner Umsetzung, obwohl der Sachverständigenrat für Umweltfragen dies seit 25 Jahren als notwendig einfordert. Der Beitrag argumentiert, dass die technischen Voraussetzungen für ein Monitoring der differenzierten Landnutzung heute bereitstehen, und diskutiert die dafür nötigen konzeptuellen Schritte. Es werden verschiedene Dimensionen bestimmt und entsprechende Indikatoren der Landschaftsstruktur vorgeschlagen, insbesondere zum Grad der Diversifizierung und der Durchmischung der intensiven Landnutzungen, zur Schlaggrößenverteilung intensiv genutzter Flächen, zum Flächenanteil naturnaher Flächen (mindestens 10 %) und zur vernetzten Anordnung der naturnahen Flächen. Des Weiteren diskutiert der Aufsatz geeignete Bezugseinheiten und vorhandene Daten. Abschließend werden verbleibende Lücken in den Datengrundlagen identifiziert und die Frage der Definition von Zielwerten erörtert.

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