37 resultados para 188-1166A
Resumo:
Eudiaptomus vulgaris Schmeil is the most abundant copepod in Lake Maggiore and forms also, in respect to other entomostraca, the most important element, through its average biomass and because it is fairly numerous throughout the year. Plankton samples collected in a systematic and quantitative way, gave the opportunity to study some aspects of the dynamics of the population of this copepod, in safety in view of the uncertainty which in this kind of study can ensue when samples are taken only at a single station - in consequence of the changes in size of population between different water masses. The results of the biometrical observations are of the population of Eudiaptomus vulgaris is presented.
Resumo:
Environmental studies of power plants have recently shifted their emphasis from examination of the effects of heated discharges to studies of the impacts of entire cooling systems. One of the major impacts arises when planktonic organisms are carried into and through a plant with the cooling water. Because of their relatively immobile, free-floating character, planktonic organisms are highly vulnerable to being "entrained" or passively drawn into the cooling water condenser systems of power plants. More than 70% of estuarine animals have planktonic eggs and larvae. The environmental impact of entrainment is related to the composition and abundance of affected organisms, the numbers of organisms in the adjacent waters, survival rates during entrainment as related to natural survival, the ecological roles of entrained organisms, and their reproductive strategies.
Resumo:
An examination is made of the organization and administration of fisheries training institutes in Nigeria, highlighting their inadequacies in achieving required goals. A systems approach to fisheries manpower training is described which is based on 4 principles: 1) wholeness; 2) systematization; 3) compatibility; and 4) optimization
Resumo:
The paper traces the history of the different documentation media used for information dissemination. Such early media are clay tablets, papyrus, and vellum or parchment codex. The invention of printing however revolutionized the information industry, enabling the production of books in multiple copies. Photography came into documentation mainly to preserve rare materials and those that easily deteriorate. This paper reports the efforts of National Institute for Freshwater Fisheries Research (NIFFR) and Kainji Lake Fisheries Promotion Project (KLFPPP), Nigeria, to develop an Object Oriented Database (OOD) using photographs. The photographs are stored in digitized form on commercial computers, using the program ACDSee 32 for classification, description and retrieval. Specifically the paper focuses on photographs in fisheries as visual communication and expression. Presently, the database contains photo documents about the following aspects of Kainji Lake fisheries: fishing gears and crafts, fish preservation methods
Resumo:
Norway’s sea fishery 1996 ranked 9th world wide. Preliminary data for 1996, as published in the Norwegean journal Fiskets Gang, show a further increase of the total catch by 114 000 tonnes, which now reached 2.63 million tonnes. The value of these landings were 8550 million nkr, up by 381 million nkr. The 5 most caught species were herring, cod, blue whiting and saithe. The 5 highest values, however, were obtained by cod, mackerel, herring, saithe and deepsea prawn. Considerable increases of prices were noted for jack mackerel (+142 %), mackerel (+133 %) and herring (+34 %).
Resumo:
Zweiter Abschnitt der 188. (70.) Reise des FFS "Anton Dohrn" vom 2.2. - 23.3.1976
Resumo:
Erster Abschnitt der 188. (70.) Reise des FFS "Anton Dohrn" vom 8.1. - 29.1.1976
Resumo:
Endoparasitic helminths were inventoried in 483 American plaice (Hippoglossoides platessoides) collected from the southern Gulf of St. Lawrence, NAFO (North Atlantic Fisheries Organization) division 4T, and Cape Breton Shelf (NAFO subdivision 4Vn) in September 2004 and May 2003, respectively. Forward stepwise discriminant function analysis (DFA) of the 4T samples indicated that abundances of the acanthocephalans Echinorhynchus gadi and Corynosoma strumosum were significant in the classification of plaice to western or eastern 4T. Cross validation yielded a correct classification rate of 79% overall, thereby supporting the findings of earlier mark-recapture studies which have indicated that 4T plaice comprise two discrete stocks: a western and an eastern stock. Further analyses including 4Vn samples, however, indicated that endoparasitic helminths may have little value as tags in the classification of plaice overwintering in Laurentian Channel waters of the Cabot Strait and Cape Breton Shelf, where mixing of 4T and 4Vn fish may occur.