Die Studie mit Fokus auf die Übernahme von Fischproduktion und konservierender Bodenbearbeitung (KB) in Sub-Sahara Afrika (SSA) verdeutlicht 1) die Komplexität von Übernahme- und Diffusionsprozessen landwirtschaftlicher Innovationen in SSA, vertieft 2) den Wissensstand zur Diffusion dieser zwei Innovationen und, leistet 3) einen Beitrag zur Entwicklung eines neuen methodischen Ansatzes für den Forschungsgegenstand. Neben der Darstellung der wesentlichen Konzepte und Literatur basieren die empirischen Daten auf semi-strukturierten Interviews, Fokusgruppendiskussionen, Teilnehmerbeobachtung und QAToCA, einem in der Studie entwickelten, partizipativen und expertenbasierten Bewertungsansatz. Die Ergebnisse zeigen, dass Fischzucht – speziell im Fall von Kamerun – eine attraktive Beschäftigung für mittelständische Landwirte ist. Zur weiteren Verbreitung dieser Innovation besteht jedoch Bedarf für 1) zielgerichtete Förderung mittelständischer Landwirte, 2) Verbesserung der Organisationsstruktur der Landwirte, 3) Stärkung des Beratungssystems, und 4) Verbesserung der Forschung für Jungfischaufzucht. Mit Anwendung von QAToCA für die Übernahme von KB zeigen die Ergebnisse i) hohes Übernahmepotential in Malawi, Sambia, Tansania, Kenia – aufgrund positiver institutioneller Faktoren, ii) geringes Übernahmepotential für Simbabwe – bezüglich der instabilen Marktlage, iii) geringes Übernahmepotential in Süd-Burkina Faso – aufgrund der Konkurrenz um Ernterückstände zwischen KB und Tierproduktion, und iv) hohes Übernahmepotential für Nord-Burkina Faso – was sich darauf zurückführen lässt, dass Alternativen zu KB nicht bestehen. Für eine anhaltende Übernahme landwirtschaftlicher Innovationen in SSA zeigt die Arbeit Handlungsbedarf auf für 1) Berücksichtigung des Bedarfs für neue Absatzmärkte, 2) Anpassung von Innovationen an bestehende Managementstrukturen von Betrieben und, 3) Entwicklung von fördernden politischen und institutionellen Rahmenbedingungen auf Dorf- und Regionalebene. / Focusing on adoption of Fish farming and Conservation Agriculture (CA) in sub-Saharan Africa (SSA), this study: 1) partly demonstrate that, the reality of adoption and diffusion of agricultural innovations in SSA is a more complex issue, 2) improve on the knowledge and understanding of diffusion for these two innovations in SSA and, 3) develop and contribute to a new methodological approach in this field of study. Apart from reviewing concepts and relevant literature, empirical data for this work was obtained by using semi structured interviews, focus group discussions and participant observation alongside a participatory expert-based assessment approach (QAToCA) - developed within this work. Results revealed that, Fish Farming especially for the case of Cameroon remains an attractive activity for medium-scale farmers. However for a sustained adoption of this innovation, there is need for 1) targeted support to medium-scale farmers, 2) improving organisational structures of farmers, 3) strengthening the fragile extension system, and, 4) improving research on fingerlings production. Following application of QAToCA in assessing CA adoption, results reveal i) high adoption potential for Malawi, Zambia, Tanzania, Kenya - explained by presence of positive institutional factors, ii) low adoption potential for Zimbabwe - attributed to unstable and less secured market conditions, iii) low adoption potential for Southern Burkina Faso - explained by strong competition of CA with livestock over residue, and iv) high adoption potential for northern Burkina Faso - explained by the fact that farmers have no alternative than to adopt CA. For long lasting adoption of agricultural innovations in SSA, this work calls for 1) addressing emerging needs for new input and output market outlets, 2) adapting innovations to existing management structures of adopting farms and, 3) developing a supportive political and institutional frame condition at village and regional levels.

Presence of coastal aquaculture activities in marine landscapes is growing. However, there is insufficient knowledge on the subsequent ecological interactions between these activities and marine fish communities. The overall aim of this thesis was to evaluate the direct and indirect ecological effects of aquaculture activities on marine fish communities in Scotland. A combination of empirical and modelling approaches was employed to collect evidence of how aquaculture activities affect marine fish communities at the individual, population and ecosystem levels around coastal sea cages. The two fish farms evaluated in this research provided the wild fish sampled near the sea cages with a habitat rich in food resources which is reflected in an overall better biological condition. Results of the stomach content analysis indicated that mackerel (Scomber scombrus), whiting (Merlangius merlangus) and saithe (Pollachius virens) sampled near sea cages consumed wasted feed which was also reflected in their modified FA profiles. The overall effects of the two fish farms were more pronounced in young whiting and saithe than in mixed aged mackerel sampled near the sea cages. The phase space modelling approach indicated that the overall potential for fish farms to act at the extremes as either population sources (a habitat that is rich in resources and leads to an overall improved fitness) or ecological traps (a habitat that appears to be rich in resources but is not and leads to an overall poor fitness) are higher for juvenile whiting than for mackerel. Based on the empirical evidence and literature the two fish farms are more likely to be a population source for wild fishes. Using an ecosystem modelling approach indicated that fish farming impacts the food web in a sea loch via nutrient loading. Mussel farming relies on the natural food resources and has the potential to affect the food web in a sea loch via competing with zooplankton for resources which can affect higher trophic levels. The presence of both activities can balance the overall impact in a sea loch as compared to the impact induced if each of these activities were present on their own. Both activities have the potential do induce direct and indirect effects on the wild fish and the entire sea loch system. The results of this PhD identified several gaps in data and thus could be used to improve future sampling designs. It is important to evaluate the cumulative effect of the presence of aquaculture activities in terms of nutrient loading and physical structure in the environment. Using a combination of empirical and modelling approaches is recommended to gain further insight into the ecological impacts of aquaculture activities on wild fish communities. Results of this PhD study could lead to more informed decisions in managing the coastal aquaculture activities. Establishing coastal fish farms as aquatic sanctuaries can be of an advantage to increase fish production and conserve species that are endangered provided that no commercial and recreational fishing is allowed nearby. It would be useful to have long term monitoring of the fish stocks around the cages and if there is any production at the regional level. Additionally, information on behaviour, migration patterns should be collected to understand the impacts of aquaculture activities on fish stocks. From an aquaculture perspective, ecologically engineered fish farms in addition to careful site selection in new aquaculture developments may improve nutrient loading into the ecosystem.

The main goals of this thesis are description of a quite complicated peled breeding topic in the Czech Republic, evaluation of inconsistent taxonomical data, biology and ecology of the Coregonus maraena and Coregonus peled. The approach to peled breeding is in detail evaluated recently as well as in the past. Methods of breeding, fishing out, fish tank breeding and fish transfer are addressed. The questionary survey among peled producers was used for critical evaluation of their experience. The factors that discourage producers from peled breeding (eutrophication, predation by cormorants or otter as well as technological difficulties) were stated. Due to these factors the peled production is limited despite the stabile market demand. The case study of peled production was realized. In the condition of huge fish stock (carp and grass carp) the main negative impacts were confirmed.

The aim of this work was to show on actual example the possibilities of financing projects in the education sphere.

Made available in DSpace on 2017-07-10T18:13:29Z (GMT). No. of bitstreams: 1 Juliana Mara Costa.pdf: 556873 bytes, checksum: b4d6f1321099600920caa72a0df212c3 (MD5) Previous issue date: 2012-07-09 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Nutrition has a fundamental importance for the success of fish farming, considering that it represents the majority costs of production. Considering that the fish absorb various nutrients in the water, although the amount of phosphorus absorbed is not sufficient for its proper development, having the need to supply it in diet. Therefore, the present work aimed to evaluate the performance, chemical composition and plasmatic phosphorus response of the different levels of phosphorus inclusion on goldfish (Carassius auratus) diets. Were used 200 fry with weight, standard and total initial length of 3,11±0,50g; 3,68±0,23cm and 5,11±0,31cm, respectively. The fish were distributed in a completely randomized design with five treatments and four replicates in 20 cages of 0,15 m3 of useful volume, made of mesh shade and installed in a circular tank. The experimental lasted for 8 months, being divided into three phases. The diets were formulated with 30% of crude protein and 2900 kcal.kg-1 of digestible energy, isoproteic and isocaloric, with 0,65, 0,80, 0,95, 1,10 e 1,25% of phosphorus concentration. The fed was realized four times a day until the fish apparent satiation. The physical and chemical water variables such as pH, electrical conductivity and dissolved oxygen were measured weekly and the temperature was monitored four times a day. At the end of the experiment, the fish were fasted for 24 h, to empty the gastrointestinal tract. After this procedure, were collected and anesthetized with solution of benzocaine (75 mg.L-1) during 15 minutes, and after that the fish were weighed and measured. Was carried out the collection of 1,0 mL of fish blood via caudal vein using disposable syringes containing EDTA (10%). For determination of phosphorus in the blood, the phosphomolybdate colorimetric method was used. It is concluded that, for the first phase, on experimental conditions, the best results of weight gain were obtained for the phosphorus inclusion levels of 0,95 and 1,10%, (P<0,05) does not influence this parameter in the other phases. For feed conversion, the best index was obtained for the phosphorus inclusion levels of 1,25%, when evaluated the complete experimental period. There was no difference in phosphorus concentration in the fish plasm. The highest value of mineral matter in the chemical composition of the animals was observed for 1,25% of phosphorus supplement (P<0,05). / A alimentação balanceada é de fundamental importância para o sucesso da piscicultura, tendo em vista que representa a maior parte dos custos de produção. Considerando que os peixes possuem a capacidade de absorver certos minerais presentes na água, a quantidade de fósforo absorvida não é suficiente para o adequado desenvolvimento dos animais, quando cultivados, havendo a necessidade de seu fornecimento pela dieta. Assim, este trabalho teve como objetivo avaliar a resposta em parâmetros zootécnicos, de composição bromatológica e de fósforo plasmático à inclusão de diferentes níveis de fósforo em dietas para kinguio (Carassius auratus). Foram utilizados 200 alevinos com peso, comprimento padrão e total inicial médio de 3,11±0,50g, 3,68±0,23cm e 5,11±0,31cm, respectivamente. Os indivíduos foram distribuídos em delineamento inteiramente casualizado, com cinco tratamentos e quatro repetições, em 20 tanques-rede de 0,15 m3 de volume útil cada, confeccionados em malha sombrite e instalados em um tanque circular de alvenaria. O período experimental teve duração de 8 meses, sendo subdividido em 3 fases, utilizando a mesma dieta mas com variação da temperatura. As dietas foram formuladas com 30% de proteína bruta e 2900 kcal.kg-1 de energia digestível, isoproteicas e isoenergéticas, com concentrações de: 0,65, 0,80, 0,95, 1,10 e 1,25% de fósforo. O arraçoamento foi realizado quatro vezes ao dia, ad libitum, até a saciedade aparente dos peixes. As variáveis físicas e químicas da água, pH, condutividade elétrica e oxigênio dissolvido, foram mensuradas semanalmente e a temperatura monitorada diariamente, quatro vezes ao dia. Ao final do experimento, os peixes foram mantidos em jejum por 24 h, para esvaziamento do trato gastrointestinal. Após este procedimento, foram coletados e anestesiados com solução de benzocaína (75 mg.L-1) durante 15 minutos e, posteriormente, pesados e medidos. Realizou-se a coleta de 1,0 mL sangue por peixe via punção da veia caudal utilizando-se seringas descartáveis contendo solução de EDTA (10%). Para determinação do fósforo no sangue, utilizou-se o método fosfomolibdato colorimétrico. Concluiu-se que, para a fase I, nas condições experimentais, obteve-se o melhor resultado para ganho em peso para os níveis de 0,95 e 1,10% de fósforo (P<0,05), não influenciando este parâmetro nas demais fases. Para conversão alimentar aparente, o melhor índice foi obtido para o nível de 1,25% de fósforo na dieta, quando avaliado o período experimental completo. Não houve diferença na concentração de fósforo plasmático dos peixes. O maior valor de matéria mineral na composição bromatológica dos animais foi verificado para 1,25% de suplementação de fósforo (P<0,05).

IN THE ENGLISH LANGUAGE The subject of my doctoral dissertation is an exploration of fishing rights as a collection of a wide range of legal norms regulating the behavior of the recipients only in the performance of fishing, but also in civil, administrative and criminal relations with the breeding and hunting fish related. Due to the current lack of scientific literature on this topic, the thesis also basic definition and status of the Czech Fishing rights in the legal system of the Czech Republic and important connections not only in relation to the institutions of environmental law, but also of civil and criminal law. Basic Institutes of fishing rights are always described as in historical context, as from the time of its inception developed, as well as in international comparisons of countries that their cultures are very close to us.

No description available.