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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.
111

Espécies hortícolas alimentares da população caiçara do sertão de ubatumirim, litoral norte de são paulo: manejo e paisagem

Macedo, Gabriela Silva Santa Rosa [UNESP] 17 July 2014 (has links) (PDF)
Made available in DSpace on 2014-12-02T11:16:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-07-17Bitstream added on 2014-12-02T11:21:37Z : No. of bitstreams: 1 000791351.pdf: 7024955 bytes, checksum: b3dcc258f3f7c9123e489ba9e8e28b6d (MD5) / Neste trabalho pretende-se diagnosticar e analisar o manejo dos recursos vegetais hortícolas alimentares da agricultura tradicional da comunidade caiçara residente no interior e entorno do Parque Estadual da Serra do Mar (PESM)- Núcleo Picinguaba- situado no estado de São Paulo relacionando-os com a orientação e interferência na paisagem. Para tanto, busca-se, à luz da Etnoecologia Abrangente, por meio de ferramentas da Etnobotânica e da Antropologia, subsídio para a análise do modo de vida das populações considerando o uso e ocupação do solo assim como a inserção e importância de espécies alimentares, cultivadas e não-cultivadas, no dia-a-dia das pessoas. Foram obtidos dados em campo por meio da observação participante e com o uso de questionários e entrevistas estruturadas e semi-estruturadas. Utilizou-se o geopreocessamento a fim de se obter um mapa a partir de unidades de paisagem reconhecidas pelos agricultores correlacionando critérios êmicos de distinção da paisagem com aspectos fitossociológicos e de diversidade. Concluiu-se que o sistema de conhecimentos, crenças e sentimentos influenciam o manejo das espécies alimentares e das paisagens afetando diretamente a conservação e variabilidade de espécies de plantas e paisagens, ainda que haja pressão para substituições e impedimentos legais. A partir da argumentação de que é possível co-existir conservação de recursos naturais em locais onde habitam comunidades tradicionais tendo em vista seu modo de vida conservacionista, espera-se que este trabalho possa trazer contribuições para programas e políticas públicas de proteção às populações que têm sua cultura comprometida por restrições da legislação de uma UC e para conservação das espécies alimentares alvo do estudo / This paper aims to diagnose and analyze the management of food plants resources of traditional agriculture of caiçara community resident in and around the Serra do Mar State Park (PESM) - Picinguaba situated in the state of São Paulo relating them to management and interference in the landscape . To do that, we seek the light of Comprehensive Ethnoecology, through tools of ethnobotany and anthropology, allowing the analysis of the way of life of the people considering the use and occupation as well as the inclusion and importance of food species, cultivated and non-cultivated, day-to-day lives. Field data were obtained through participant observation and the use of questionnaires and structured and semi-structured interviews. We used the geoprocessing in order to obtain a map from landscape units recognized by farmers correlating emic criterion for distinguishing the landscape with phytosociological and diversity aspects. We can conclude that the system of knowledge, beliefs and feelings influence the management of food plants species and landscapes directly affecting the conservation and variability of plant species and landscapes, although there is pressure to substitutions and legal impediments. From the argument that it is possible to co -exist conservation of natural resources in places with traditional communities considering their conservationist way of life, it is expected that this work will bring contributions to public programs and policies to protect the people who have their culture compromised by restrictions in the laws of a Conservation Unit (UC) and to the conservation of targeted food plants of this study
112

Atributos físicos e químicos do solo sob cultivos de outono-inverno em sistema de semeadura direta /

Sereia, Rodrigo César, 1986. January 2014 (has links)
Orientador: Maria Helena Moraes / Coorientador: Gessí Ceccon / Banca: José Eduardo Corá / Banca: Sergio Lazaro de Lima / Resumo: Os atributos físicos e químicos do solo caminham lado a lado, e a ciência busca aprimorar o entendimento a respeito da interação dos mesmos, visando contemplar a sustentabilidade pela conservação do solo e de seus recursos naturais, utilizando o próprio sistema solo como uma ferramenta para redução das práticas antrópicas. O objetivo desse estudo foi avaliar os atributos físicos e químicos do solo submetido a diferentes cultivos de outono-inverno estabelecidos há cinco anos em sistema de semeadura direta e esclarecer qual a influência desses atributos na produtividade de grãos da soja. O experimento foi conduzido em Latossolo Vermelho distroférrico de textura argilosa. Foram estabelecidos quatro tratamentos de outono-inverno, Brachiaria ruziziensis (B), milho (M), milho consorciado com Brachiaria ruziziensis (M+B) e feijão caupi (C) e no verão foi cultivado soja. Foram realizadas coletas de solo, durante o período de florescimento da soja, para as análises física e química, foram retiradas também amostras de raízes da soja. Ao final do experimento foi realizada a colheita da soja para determinar a produtividade de grãos. Houve redução da macroporosidade e aumento da densidade do solo em B, comparado aos demais tratamentos, decorrente do pisoteio dos animais. O feijão caupi proporcionou maior retenção de água nas camadas abaixo de 0,10 m. Os maiores DMP e DMG foram encontratados em B, M, e M+B e os menores em C. O cultivo B apresentou maior percentagem da massa do solo distribuída em agregados >2,0 mm, em todas as camadas, enquanto que em C houve a menor proporção dos agregados maiores que 2,0 mm nas camadas abaixo de 0,10 m. M e M+B tiveram estabilidade de agregados intermediária entre B e C. Não houve diferença na resistência a penetração (RP) entre os tratamentos estudados, esta apenas variou com a profundidade e foi maior na segunda e terceira camadas ... / Abstract: The physical and chemical soil attributes go hand in hand, and science seeks to improve the understanding about the interaction of these, aiming to include sustainability through conservation of soil and its natural resources, using the own soil system as a tool to reduce anthropogenic practices. The aim of this study was to evaluate the physical and chemical soil properties under different crops in autumn-winter established five years ago in no-tillage system and clarify the influence of these attributes on the grain yield of soybean crop and its root growth. The experiment was conducted on an Oxisol clay texture. Four treatments autumn-winter, were established, Brachiaria ruziziensis (B), maize (M), maize intercropped with B. ruziziensis (M+B) and cowpea (C) and in summer was grown soybeans. Samplings were carried out during soybean flowering, for the analysis of physics and chemistry, were also taken samples of soybean roots. At the end of the experiment proceeded soybean harvest to determine grain yield. There was a decrease in the macroporosity and an increase in bulk density of the soil in the B treatment compared to the other treatments, due to the animal trampling. The cowpea provided greater water retention in the layers below 0,10 m, due to the smaller influence of roots of this crop and higher microporosity in the soil. The largest Mean Geometric Diameter (MGD) and Mean Weight Diameter (MWD) were observed in treatments B, M, and M+B and the lowest values in C. Treatment B had higher percentage of soil mass distributed in aggregates > 2,0 mm in all layers, while in treatment C there was the lowest aggregate stability (> 2,0 mm) in the layers below 0.10 m. M and M + B had intermediate stability of aggregates between treatments B and C. There was no difference in resistence to penetration (RP) between the treatments, this only varied with depth and was higher in the second and third layer ... / Mestre
113

Short- and Long-Term Influences of Education, Health Indicators, and Crime on Labor Market Outcomes : Five Essays in Empirical Labor Economics

Lång, Elisabeth January 2017 (has links)
The objective of this thesis is to improve the understanding of how several individual characteristics, namely education (years of schooling), health indicators (height, weight, smoking, alcohol consumption, and exercise), criminal behavior, and crime victimization, influence labor market outcomes in the short and long run. The first part of the thesis consists of three studies in which I adopt a within-twin-pair difference approach to analyze how education, health indicators, and earnings are associated with each other over the life cycle. The second part of the thesis includes two studies in which I use field experiments in order to test the employability of exoffenders and crime victims. The first essay, Learning for life?, describes an analysis of the education premium in earnings and health-related behaviors throughout adulthood among twins. The results show that the education premium in earnings, net of genetic inheritance, is rather small over the life cycle but increases with the level of education. The results also show that the education premium in health-related behaviors is mainly concentrated on smoking habits. The influences of education on earnings and health-related behaviors seem to work independently of each other, and there are no signs that health-related behaviors influence the education premium in earnings or vice versa. The second essay, Blowing up money?, details an analysis of the association between smoking and earnings in two different historical social contexts in Sweden: the 1970s and the 2000s. I also consider possible differences in this association in the short and long run as well as between the sexes. The results show that the earnings penalty for smoking is much stronger in the 2000s as compared to the 1970s (for both sexes) and that it is larger in the long run as compared to the short run (for men). The third essay, Two by two, inch by inch, describes an analysis of the height premium among Swedish twins. The results show that the height premium is relatively constant over the life cycle and that it is larger below median height for men and above median height for young women. The estimates are similar for monozygotic and dizygotic twins, indicating that environmentally and genetically induced height differences are similarly associated with earnings over the life cycle. The fourth essay, The employability of ex-offenders, published in IZA Journal of Labor Policy (2017), 6:6, details an analysis of whether male and female exoffenders are discriminated against when applying for jobs in the Swedish labor market. The results show that employers do discriminate against exoffenders but that the degree of discrimination varies across occupations. Discrimination against ex-offenders is pronounced in female-dominated and high-skilled occupations. The magnitude of discrimination against exoffenders does not vary by applicants’ sex. The fifth essay, Victimized twice?, describes an analysis of whether male and female crime victims are discriminated against when applying for jobs in the Swedish labor market. This study is the first to consider potential hiring discrimination against crime victims. The results show that employers do discriminate against crime victims. The discrimination varies with the sex of the crime victim and occupational characteristics and is concentrated among high-skilled jobs for female crime victims and among femaledominated jobs for male crime victims.
114

Non-phytotoxic concentration of nemarioc-AL and nemafric-BL phytonematides on green bean cultivar "Tahoe"

Chokoe, Francinah Mologadi January 2017 (has links)
Thesis ( M.Sc.(Horticulture)) -- University of Limpopo, 2017. / Refer to document / National Research Foundation of South Africa, and the Agricultural Research Council-Universities Collaboration Centre
115

Learning about marine cloud brightening: detectability of field experiments, benefits and risks of implementation

VIJAYAN NAIR, ASWATHY 12 April 2018 (has links)
The main objectives of the thesis are to learn about the detection of a hypothetical marine cloud brightening (MCB) field experiment and to assess the benefits and risks of an actual implementation using model simulations. The first aim of the thesis is to assess the detectability of MCB from the natural variability of clouds using satellite data. The analysis uses two approaches, i) an analytical method, assessing the radiative forcing by aerosol-cloud interactions for an idealised perturbation of the droplet concentration and ii) a stochastic method, including the radiative forcing and the cloud adjustment effects of perturbing the cloud droplet number concentration. One of the main findings of the study is that in the analytical method, detection of an MCB experiment in the North Pacific region requires longer duration, larger domain and larger intensity of the Nd perturbation than in the South Pacific and the South Atlantic regions. In the Stochastic method, larger domain size as well as longer duration are required for the detection of the hypothetical field experiments compared to the analytical method. We found that increasing the duration of the experiment and intensity of Nd perturbation has more influence in detectability than increasing the domain size. Secondly, we analyse the detection of MCB using ECHAM GCM simulations. Two methods are used for the analysis, i) a temporal method, using temporal reference of nine years for the analysis, and ii) a spatial method, where a surrounding unperturbed regions are used as a reference for the analysis. In the temporal method, the detectability of the MCB experiment over the North Pacific region is most difficult. Our calculations suggest that for an experiment to be cost effective, it is preferable to design an experiment of longer duration with smaller domain sizes as well as less intensity of perturbation of Nd. Finally, we investigate the effectiveness of MCB in alleviating the changes in the mean and extremes for surface air temperature and precipitation. We compare these results with another climate engineering technique, namely stratospheric aerosol injection. The study is based on an existing multi model simulation of three Earth system models. The main conclusion from the study is that the two solar radiation management techniques are rather effective in mitigating the climate change driven increases in the mean and extremes of temperature and precipitation according to the climate simulations. However, the potential to mitigate differs around the globe and seasonally. The strong increases in lower temperature extremes, especially in the Arctic, are not well dampened with the solar radiation management implementation.
116

Transgena träd i fältförsök : Trender, beslut och inställningar. Var har vi varit och vart är vi påväg?

Lycksell, Johanna January 2023 (has links)
With genetic engineering desirable characteristics can be introduced or enhanced in organisms. Furthermore, transgenic trees have shown promising results in greenhouse and field trials. Results on transgenic trees in field trials have been published but international and detailed compilations of what has been carried out are limited. To get an overview of the development of genetic engineering and genetically modified trees in the field, a meta-study has been carried out with information from public databases, books, and other publications. The study focused on transgenic trees in field experiments, excluding fruit trees. Traits that have been modified have been compiled. Furthermore, trends, patterns, and deviations were analyzed for the following parameters: tree species, characteristics and the years in which field trials were conducted or permitted. The countries included in this study were the EU (European Union), USA, and Brazil. Results indicate that different species of poplar and eucalyptus were the most studied tree species while resistance, growth and wood properties were the mainly investigated traits. When comparing the number of field trials that were started and got permission until 2000 and after 2001 respectively, there was an increasing trend in all study areas. However, significant results were demonstrated only for the USA. When comparing field trials until 2010 respectively after 2011, there was an increasing trend in the EU and Brazil, but not in the USA. The difference was only significant for the EU.
117

Thermogravimetry – a promising technique to assess the status of organic matter supply in agricultural soils

Tokarski, David 23 December 2020 (has links)
The aim of this thesis was the experimental evaluation of thermogravimetry (TG) to assess the status of organic matter supply in agricultural soils. TG is an innovative analytical method for recording thermal mass losses (TML) during heating of soil samples from room temperature to 950 °C. The determination of TML in 10 °C temperature increments (TG indicators) is a central method of TG data evaluation. There is a very close correlation between selected temperature ranges and classically determined soil properties (organic carbon, total nitrogen and clay content). The regression parameters of these relationships can be used to estimate soil properties and to assess the quality of SOM.:List of Tables VI List of Figures VII List of Abbreviations VIII Summary 10 Zusammenfassung 13 Chapter One – Synthesis: Thermogravimetry – a promising technique to assess the status of organic matter supply in agricultural soils 16 1 Introduction 16 1.1 Soils and agriculture 16 1.2 The Importance of soil organic matter (SOM) 17 1.3 Current challenges in the assessment of SOM as an indicator of soil quality 18 1.4 Main objectives 20 2 Methodological Approach 22 2.1 General approach 22 2.2 Experimental areas and soil description 22 2.3 Application of thermogravimetric analysis (TG) 28 2.4 Experimental design 29 2.4.1 SOC content determination using TML (chapter two and chapter five) 29 2.4.2 Detectability of thermal stabilities of organic amendments in soil samples using TML (chapter two) 30 2.4.3 Comparison between biological and thermal stability of SOM (chapter two and chapter three) 30 2.4.4 Linking thermogravimetric data with soil properties, thermal stability of SOM and SOC fractions (chapter four and chapter five) 31 3 Results and Discussion 32 3.1 Thermogravimetric-based fingerprint predictions of soil properties and soil organic matter stability (chapter two and chapter three) 32 3.2 Linking thermogravimetric indicators with functional SOC fractions to assess SOM quality (chapter four and chapter five) 35 4. Research needs and perspectives 37 5. Conclusion 40 References 40 Chapter Two: Contribution of organic amendments to soil organic matter detected by thermogravimetry 51 Chapter Three: Detectability of degradable organic matter in agricultural soils by thermogravimetry 52 Chapter Four: Linking soil organic matter thermal stability with contents of clay, bound water, organic carbon and nitrogen 53 Chapter Five: Linking thermogravimetric data with soil organic carbon fractions 54 Appendix 55 List of publications 55 Acknowledgments 56
118

Winter survival of bermudagrass (Cynodon sp.) as influenced by traffic, mineral nutrition, plastic covers, cultural treatments, overseeding and freezing in late-winter dormancy

Henry, Michael L. January 1985 (has links)
The most important problem in using bermudagrass (Cynodon sp.) for turf at the northern limit of its adaptation is winter survival. Bermudagrass used for athletic complexes is exposed to the additional problem of uncontrolled or excessive traffic. This research was conducted to determine the effects of: 1) traffic and mineral nutrition; 2) clear plastic covers and cultural treatments and; 3) overseeding and late winter freezing on bermudagrass winter survival. Four separate experiments were conducted on field cultured Midiron bermudagrass. Various regimes of traffic, N and K fertility, clear plastic covers, cultural treatments and growth regulators were utilized to determine their affect on bermudagrass winter survival. A laboratory freeze was used, in two experiments, on plant samples taken from the field. Following the freezing procedure, the samples were then grown in the greenhouse. From these experiments, it was found that traffic applied just as turf growth initiates in the spring was the most damaging. Potassium fertility had no effect on post dormancy growth. Nitrogen did improve post dormancy growth of bermudagrass exposed to a late winter laboratory freeze and when plastic covers were applied during winter dormancy. Plastic covers enhanced post dormancy growth and offset the detrimental effect of imposed traffic. 'Stayz Green' turf colorant did increase early post dormancy growth. While, the cultivation treatments using a vertical mower alone and with an aerifier reduced early green up. Flurprimidal reduced early post dormancy growth of bermudagrass; while, mefluidide had no detrimental effect. Both growth regulators reduced the growth of the overseeded ryegrass, and mefluidide enhanced the competitiveness of bermudagrass in the ryegrass canopy. / M.S.
119

Effect of treating corn stover with aqueous ammonia and urea on nutritional value

Obamehinti, Johnson Muftau 20 November 2012 (has links)
Experiments were conducted to study the effect of treatment of rectangular bales of corn stover with aqueous ammonia and urea solutions. The stacks were covered with polyethylene sheets for 129 d, after which they were uncovered, aerated and sampled for laboratory analyses. / Master of Science
120

Response of corn to high levels of CuSO₄ and ZnSO₄ applications

Winarko, Clementinus 14 November 2012 (has links)
Copper and Zn deficiencies of crop plants occur in various areas throughout the world. The sulfate forms of Cu and Zn are generally used to correct these micronutrient deficiencies. In agricultural practices, Cu and Zn are applied to soils not only as a fertilizer but also as manures, pesticides and waste materials such as sewage sludge. High levels of Cu and Zn application to agricultural soils are considered to pose a potential hazard to plants and animals. Research findings have not established Cu and Zn levels that either injure plants or increase Cu and Zn concentrations in edible plant portions to undesirably high levels. Published data on the fate of applied Cu and Zn indicate that there is little, if any, downward movement of these micronutrients in soils and that, with time, applied Cu and Zn revert to plant unavailable forms in soils. / Master of Science

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