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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

Systematics and biogeography of Mesobola brevianalis (Boulenger, 1908) (Teleostei: Cyprinidae)

Riddin, Megan Amy January 2015 (has links)
The accurate identification of fish species, their life stages and their products enables the correct management of fisheries, research and conservation of distinctive populations for long-term survival and sustainability. Mesobola brevianalis Boulenger, 1908, commonly known as the river sardine, is found in many river systems in southern Africa. Because it exhibits widely separated populations showing subtle differences, particularly in colour, it is thought that there may be cryptic species involved. Standard phylogenetic techniques using three genetic markers (mitochondrial COI, nuclear protein RAG1 and nuclear ribosomal 28S rRNA), enabled the building of phylogenetic networks for M. brevianalis and some outgroup species. Consistent patterns of relationship were seen with 28S supporting monophyly. COI and RAG1 suggested that populations that are currently identified as M. brevianalis in fact represent several species. There was sufficiently strong support for the evolutionary independence of the M. brevianalis populations from the Rovuma, Kunene and Orange River Systems to consider them as independent species. The independence of the genus Mesobola was brought into question because Engraulicypris sardella and Rastrineobola argentea were placed within it phylogenetically.Morphometric methods in the form of multivariate truss network analyses, were performed to locate morphological markers for populations. There was little to no variation among most of the populations synonymized under M. brevianalis. Furthermore, neither latitude nor longitude had an effect on the morphological characters that might be linked to functional evolution. A molecular clock analysis of COI data was used to calibrate a paleobiogeographical model which entailed a divergence of lineages starting from an easterly reigning Paleo-Congo Basin, via a hypothetical Paleo-Kalahari Lake that was fragmented by a series of uplifts and drying events beginning ~65 million years ago. Complete evidence supported the synonymisation of the genera Engraulicypris and Mesobola, the resurrection of the species name gariepinus for the Orange River Systempopulation, and the description of two new species: E. ngalala from the Rovuma River System and E. howesi from the Kunene River System.
2

A study of the population dynamics, production and potential yield of the sardine Limnothrissa Miodon (Boulenger) in Lake Kariba

Marshall, Brian Eric January 1987 (has links)
The limnology of Lake Kariba, especially those aspects that affect sardine biology, are described. The hydrological regime of the lake is seen as a major influence and may be one of the reasons why the fish are very much smaller in Kariba than they are in Lakes Tanganyika or Kivu. Growth was reassessed and there appeared to be a correlation between rates of growth and limnological parameters. In particular, the fish appeared to grow faster, but smaller, in the man-made lakes and this may be a consequence of food shortages brought about by their hydrological characteristics. Mortality rates were also much higher in Kariba and this tended to support the view that the lake is a relatively unsuitable habitat for the sardines. However, estimates of biomass, expressed in terms of lake volume, contradicted this as they were very similar in both Kariba and Tanganyika. The life history strategy of Limnothrissa in Kariba was therefore to reduce its size and increase its productivity in order to maintain the maximum possible biomass and its very high P/B̄ ratio was probably the means by which this was achieved. In terms of lake volume the predicted yields from the pelagic communities of Kariba and Tanganyika were very similar, equivalent to about 20 000 t annually for Kariba. This is close to the yield predicted by several empirical models and the fishery now appears to be entering a phase where increases in effort will not be matched by increased yields. The mechanisms for controlling effort in the fishery appear to be inadequate and particular concern was expressed about the lack of co-ordination between the Zimbabwean and Zambian fishery authorities in planning the development of this shared resource.
3

Analyse, Integration und webbasierte Visualisierung von Raster- und Vektor-Daten für Renaturierungsprojekte

Heinz, Elina 22 October 2021 (has links)
No description available.
4

On the calculation of pelagic fish shoal tonnage by nighttime aerial observation

Cram, David Lindsay January 1977 (has links)
Contains published articles. / Bibliography: pages 192-208.
5

Avaliação de condições de consumo da sardinha fresca, descongelada e processada, através de substâncias que reagem com o ácido tiobarbitúrico e do nitrogênio de bases voláteis totais / Evaluation of consumption conditions of fresh, defrosted and processed sardines through thiobarbituric acid reacting substances and total volatile base nitrogen

Pereira, Alvaro Augusto Feitosa 19 March 2004 (has links)
O presente trabalho foi motivado pelas condições de comercialização da sardinha verdadeira (Sardinella brasiliensis) fresca, descongelada e processada no município de São Paulo-SP, aparentemente não adequadas. Amostras de sardinhas foram analisadas usando como parâmetros os valores de substâncias que reagem com o ácido tiobarbitúrico (TBARS) e nitrogênio de bases voláteis totais (N-BVT). As amostras foram coletadas e analisadas em três momentos diferentes da cadeia produtiva: ao desembarque na CEAGESP (Companhia de Entrepostos e Armazens Gerais do Estado de São Paulo), durante a comercialização em feiras-livres antes da vigência do defeso da espécie e durante a comercialização em feiras-livres na vigência do defeso da espécie (dezembro a março). Para a sardinha desembarcada na CEAGESP, foram observados os seguintes valores médios ± desvio-padrão: TBARS= 0,18 ± 0,17 mg de aldeído malônico (AM)/ kg e N-BVT= 15,75 ± 2,39 mg/ 100 g. Para a sardinha comercializada em feira-livre antes do defeso, os valores registrados foram TBARS= 0,82 ±0,63 mg AM/ kg e N-BVT= 27,06 ± 2,18 mg/ 100g. Para a sardinha comercializada em feira-livre durante o defeso foram detectados TBARS= 7,14 ± 5,36 mg AM/ kg e N-BVT= 27,69 ± 2,80 mg/ 100 g . Os resultados mostraram haver, para os valores de TBARS, diferença estatisticamente significativa entre a sardinha desembarcada na CEAGESP e a comercializada em feira-livre antes do defeso, bem como entre estas e as comercializadas na vigência do defeso. Já para os valores de N-BVT foi notada diferença estatisticamente significativa entre a sardinha desembarcada na CEAGESP e as comercializadas em feira-livre, porém não houve diferença estatisticamente significativa entre as sardinhas comercializadas em feira-livre antes e durante a vigência do defeso. Na sardinha salmourada foram verificados valores médios de TBARS= 4,07 ± 1,22 mg AM/ kg e N-BVT= 44,32 ± 14,38 mg/ 100 g quando não-lavada; e TBARS= 1,25 ± 0,23 mg AM/ kg e N-BVT= 39,63 ± 4,00 mg/ 100 g quando lavada. Para a sardinha anchovada foram detectados os valores médios de TBARS= 3,71 ± 0,77 mg AM/ kg e N-BVT= 62,96 ± 9,33 mg/ 100 g. Foram ainda comparados valores de TBARS e lisina biodisponível, não se observando correlação significativa entre eles (R2= 0,1732). Apenas a sardinha fresca comercializada na CEAGESP apresentou condição aceitável de consumo. / This work was motivated by the observation of the apparently not adequate trade conditions of the fresh, defrosted and processed Brazilian sardine (Sardinella brasiliensis) in the city of São Paulo-SP. Sardine samples were analysed for thiobarbituric acid reacting substances (TBARS) and total volatile base nitrogen (TVB-N). The samples were collected and analysed at three different times in the production chain: on landing at CEAGESP (the Central Warehouse Company of the State of São Paulo), while on sale at the street markets before the species-catching prohibition and while on sale at the street markets during the species-catching prohibition period (December-March). The following results were observed for the sardine landed at CEAGESP (mean ± standard deviation): TBARS= 0.18 ± 0.17 mg malondialdehyde (MDA)/ kg and TVB-N= 15.75 ± 2.39 mg/ 100 g. For the sardines collected at the street markets before the prohibition period, the results were TBARS= 0.82 ± 0.63 mg MDA/ kg and TVB-N= 27.06 ± 2.18 mg/ 100 g. The values detected for the samples collected at the street markets during the prohibition period were TBARS= 7.14 ± 5.36 mg MDA/ kg and TVB-N= 27.69 ± 2.80 mg/ 100 g. The results show a statistically significant difference between the TBARS values for the samples collected at CEAGESP and the ones collected at the street markets before the prohibition period and between the latter and the ones collected at the street markets during the prohibition period. On the other hand, a statistically significant difference was noticed between the TVB-N values for the sardines collected at CEAGESP and the ones collected at the street markets, but there was not any statistically significant difference between the samples collected at the street markets before and during the prohibition period. In unwashed brined sardines the following values were recorded: TBARS= 4.07 ± 1.22 mg MDA/ kg and TVB-N= 44.32 ± 14.38 mg/ 100 g, while for the washed samples the results were TBARS= 1.25 ± 0.23 mg MDA/ kg and TVB-N= 39.63 ± 4.00 mg/ 100 g. For ripened sardine values of TBARS= 3.71 ± 0.77 mg MDA/ kg and TVB-N= 62.96 ± 9.33 mg/ 100 g were detected. TBARS values were also compared to available lysine and no significant correlation was found (R2= 0.1732). Only the fresh sardines landed at CEAGESP showed acceptable condition for consumption.
6

Avaliação de condições de consumo da sardinha fresca, descongelada e processada, através de substâncias que reagem com o ácido tiobarbitúrico e do nitrogênio de bases voláteis totais / Evaluation of consumption conditions of fresh, defrosted and processed sardines through thiobarbituric acid reacting substances and total volatile base nitrogen

Alvaro Augusto Feitosa Pereira 19 March 2004 (has links)
O presente trabalho foi motivado pelas condições de comercialização da sardinha verdadeira (Sardinella brasiliensis) fresca, descongelada e processada no município de São Paulo-SP, aparentemente não adequadas. Amostras de sardinhas foram analisadas usando como parâmetros os valores de substâncias que reagem com o ácido tiobarbitúrico (TBARS) e nitrogênio de bases voláteis totais (N-BVT). As amostras foram coletadas e analisadas em três momentos diferentes da cadeia produtiva: ao desembarque na CEAGESP (Companhia de Entrepostos e Armazens Gerais do Estado de São Paulo), durante a comercialização em feiras-livres antes da vigência do defeso da espécie e durante a comercialização em feiras-livres na vigência do defeso da espécie (dezembro a março). Para a sardinha desembarcada na CEAGESP, foram observados os seguintes valores médios ± desvio-padrão: TBARS= 0,18 ± 0,17 mg de aldeído malônico (AM)/ kg e N-BVT= 15,75 ± 2,39 mg/ 100 g. Para a sardinha comercializada em feira-livre antes do defeso, os valores registrados foram TBARS= 0,82 ±0,63 mg AM/ kg e N-BVT= 27,06 ± 2,18 mg/ 100g. Para a sardinha comercializada em feira-livre durante o defeso foram detectados TBARS= 7,14 ± 5,36 mg AM/ kg e N-BVT= 27,69 ± 2,80 mg/ 100 g . Os resultados mostraram haver, para os valores de TBARS, diferença estatisticamente significativa entre a sardinha desembarcada na CEAGESP e a comercializada em feira-livre antes do defeso, bem como entre estas e as comercializadas na vigência do defeso. Já para os valores de N-BVT foi notada diferença estatisticamente significativa entre a sardinha desembarcada na CEAGESP e as comercializadas em feira-livre, porém não houve diferença estatisticamente significativa entre as sardinhas comercializadas em feira-livre antes e durante a vigência do defeso. Na sardinha salmourada foram verificados valores médios de TBARS= 4,07 ± 1,22 mg AM/ kg e N-BVT= 44,32 ± 14,38 mg/ 100 g quando não-lavada; e TBARS= 1,25 ± 0,23 mg AM/ kg e N-BVT= 39,63 ± 4,00 mg/ 100 g quando lavada. Para a sardinha anchovada foram detectados os valores médios de TBARS= 3,71 ± 0,77 mg AM/ kg e N-BVT= 62,96 ± 9,33 mg/ 100 g. Foram ainda comparados valores de TBARS e lisina biodisponível, não se observando correlação significativa entre eles (R2= 0,1732). Apenas a sardinha fresca comercializada na CEAGESP apresentou condição aceitável de consumo. / This work was motivated by the observation of the apparently not adequate trade conditions of the fresh, defrosted and processed Brazilian sardine (Sardinella brasiliensis) in the city of São Paulo-SP. Sardine samples were analysed for thiobarbituric acid reacting substances (TBARS) and total volatile base nitrogen (TVB-N). The samples were collected and analysed at three different times in the production chain: on landing at CEAGESP (the Central Warehouse Company of the State of São Paulo), while on sale at the street markets before the species-catching prohibition and while on sale at the street markets during the species-catching prohibition period (December-March). The following results were observed for the sardine landed at CEAGESP (mean ± standard deviation): TBARS= 0.18 ± 0.17 mg malondialdehyde (MDA)/ kg and TVB-N= 15.75 ± 2.39 mg/ 100 g. For the sardines collected at the street markets before the prohibition period, the results were TBARS= 0.82 ± 0.63 mg MDA/ kg and TVB-N= 27.06 ± 2.18 mg/ 100 g. The values detected for the samples collected at the street markets during the prohibition period were TBARS= 7.14 ± 5.36 mg MDA/ kg and TVB-N= 27.69 ± 2.80 mg/ 100 g. The results show a statistically significant difference between the TBARS values for the samples collected at CEAGESP and the ones collected at the street markets before the prohibition period and between the latter and the ones collected at the street markets during the prohibition period. On the other hand, a statistically significant difference was noticed between the TVB-N values for the sardines collected at CEAGESP and the ones collected at the street markets, but there was not any statistically significant difference between the samples collected at the street markets before and during the prohibition period. In unwashed brined sardines the following values were recorded: TBARS= 4.07 ± 1.22 mg MDA/ kg and TVB-N= 44.32 ± 14.38 mg/ 100 g, while for the washed samples the results were TBARS= 1.25 ± 0.23 mg MDA/ kg and TVB-N= 39.63 ± 4.00 mg/ 100 g. For ripened sardine values of TBARS= 3.71 ± 0.77 mg MDA/ kg and TVB-N= 62.96 ± 9.33 mg/ 100 g were detected. TBARS values were also compared to available lysine and no significant correlation was found (R2= 0.1732). Only the fresh sardines landed at CEAGESP showed acceptable condition for consumption.
7

Qualitative analysis of sardine and anchovy oscillations and implications for the management of sardine and anchovy fisheries in Oman

Al-Jufaili, Saud M. 12 June 2002 (has links)
Sardines and anchovies are small pelagic fishes that support important commercial fisheries around the world. This project reviews the inverse cyclic behavior in the abundance of these two stocks, which is a striking feature in many regions. In addition, the project used qualitative loop analysis techniques to analyze the feasible sardine-anchovy model configurations that result in the inverse relationship between sardines and anchovies. A simple community model was examined that considers fishing, sardine and anchovy biomass, and food resources for the sardines and anchovies. First, the stability of these model configurations was investigated to determine the conditions that should be met to stabilize the unstable configurations. Second, the behavior of the feasible sardine-anchovy model configurations was examined when fishing was removed from the models. Finally, model configurations were identified that best represent the sardine-anchovy system in terms of predicting qualitative changes in the system variables. These best models define the crucial interactions between sardines and anchovies that require further studies. Based on the results of the literature review and the loop analysis a set of questions was developed and used in interviews with fishers in Oman to investigate whether the sardines and anchovies in Oman are inversely related. Based on the survey results and lessons learned from the literature review and loop analysis, recommendations were developed for further research and management of the fisheries in Oman for sardines and anchovies. In systems where the sardines and anchovies vary inversely in abundance refuge areas for the sardines and anchovies are very important for maintaining the two fish stocks and their cyclic behavior. The results from the loop analysis suggested that interactions between sardines and anchovies (e.g., competition and amensalism) are not important provided the two fish populations can regulate themselves by means of their refuge areas. The expansion and contraction of sardines and anchovies is a function of environment suitability and long-term shifts in the environmental regime. The study found no evidence that sardines and anchovies in Oman are inversely related. / Graduation date: 2003
8

Extraction de lipides en voie aqueuse par bioréacteur enzymatique combiné à l'ultrafiltration application à la valorisation de co-produits de poisson (Sardina pilchardus) /

Dumay, Justine Jaouen, Pascal. Bergé, Jean-Pascal Barnathan, Gilles. January 2006 (has links)
Thèse doctorat : Génie des procédés : Université de Nantes : 2006. / Bibliogr. p. 284-303. Index.
9

Shaping the shoreline : environment, society, and culture in Monterey, California /

Chiang, Connie Young. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 356-394).
10

Obtenção, caracterização e utilização de farinha de silagem de sardinha na formulação de rações para camarão / Obtaintion, characterization and use of sardine silage meal in shrimp feed formulation

Boelter, Juliana Ferreira 13 December 2010 (has links)
Made available in DSpace on 2015-04-17T14:49:45Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1312585 bytes, checksum: fbb9ae4e44e8f9ce58da93108370cbc4 (MD5) Previous issue date: 2010-12-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Carciniculture is a relevant economic activity, which grows each day worldwide. Currently, the most cultivated species in the world is Litopenaeus vannamei, because of its hardiness, adaptability and high growth in different environmental conditions, generating good levels of productivity, excellent meat quality and good market acceptance. The feeds are responsible for a considerable share of operacional costs of cultivation, and the protein source is the most expensive component. Fish meal is traditionally used, although its high cost and limited supply. Based on this, the search for ingredients to replace fish meal is becoming increasingly necessary. This study consisted in making a sardine waste silage meal, which was used to replace, in different proportions, the fish meal in feeds. The chemical composition of the six diets prepared and the control diet were determined, as well as their thermal, physical and microbiological stabilities. Juveniles of L. vannamei were fed for 40 days, and were evaluated in the biomass gain and survival rate. The ensiling process was fast, convenient and economical. The sardine silage meal showed good levels of protein, minerals and lipids. The formulated diets had superior physical stability compared with the commercial feed, and good thermal and microbiological stabilities. Good results in groth were observed from 60% replacement of fish meal by silage meal, and total replacement was the most effective in weight gain, and besides providing good results, use an inexpensive technique and removes from the environment potentially polluting waste. / A carcinicultura é uma atividade econômica relevante, que cresce a cada dia em âmbito mundial. Atualmente, a espécie mais cultivada no mundo é Litopenaeus vannamei, devido à sua rusticidade, alta capacidade de adaptação e crescimento em diferentes condições ambientais, gerando bons níveis de produtividade, excelente qualidade da carne e boa aceitação no mercado. As rações são responsáveis por uma parte considerável dos custos operacionais de cultivo, e a fonte protéica é o componente mais caro. Tradicionalmente é usada a farinha de peixe, que além do alto custo possui oferta limitada. Visto isso, a procura por ingredientes que substituam a farinha de peixe é cada vez mais necessária. Este estudo consistiu na fabricação de uma farinha de silagem de resíduos de sardinha, que foi utilizada para substituir, em diferentes proporções, a farinha de peixe em rações formuladas artesanalmente. A composição química das seis dietas elaboradas e da ração controle foram determinadas, assim como suas estabilidades térmica, física e microbiológica. Os juvenis de L. vannamei foram alimentados durante 40 dias, sendo avaliados o ganho de biomassa e a taxa de sobrevivência. O processo de ensilamento mostrou-se rápido, prático e econômico. A farinha de silagem de sardinha apresentou bons níveis de proteína, minerais e lipídios. As rações formuladas apresentaram estabilidade física superior às rações comercias, além de boa estabilidade térmica e microbiológica. Bons resultados em crescimento foram observados a partir de 60% de substituição de farinha de peixe por farinha de silagem, sendo a substituição total a mais eficiente em ganho de peso, mostrando-se vantajosa, pois além de proporcionar bons resultados, utiliza uma técnica pouco onerosa e retira do ambiente resíduos potencialmente poluidores.

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