931 resultados para Simonsen, Mario Henrique, 1935-1997 - Contribuições em economia
Resumo:
The demersal fish stock of Wadge Bank is one of the important fish resources for both Sri Lanka and India. Sivalingam and Medcof (1957) have given an account of its history, general features and relative productivity. According to records the total fishing effort on the bank had been fluctuating and very recently the number of boats operating on the bank has suddenly increased, and there is a possibility that still more will begin operating on the bank in the near future (Mendis, 1965). The increased fishing effort with the possibility of still further increase calls for proper management practices by those concerned, in order to obtain the maximum sustained yield from the demersal stock. For this purpose a detailed study of the past performance of the fishery is essential. With this in view all records of commercial operations up to 1960 are being analysed by the present author and are to be published in a series. This is the first paper in the series and gives a detailed analysis of the first commercial trawling operations from 1928 to 1935. Since there had been a major break of about 10 years between this and the present fishery this data is being analysed separately.
Resumo:
About 20% of Uganda territory is surface water from which 250,000m tons of fish is produced. In addition to fish exports which earned the country US$ 40m in 1996, fish provides 50% of protein diet of the 20m people translating into a per capita consumption of 12kg. It is estimated that fishery related activities employ at least one million people.The goal of FIRRI is to generate and transfer improved technologies and policy recommendations aimed at ensuring sustainable fish production and a healthy environment in which fish is produced.
Resumo:
Small pelagic fish species are mainly caught by gill nets operated by fibre reinforced plastic boats fitted with 8-25hp out board engines, traditional crafts fitted with 8-1hp out board engines and non mechanised traditional crafts. Around 28 to 55% of the small pelagic catch in the study area consisted of trenched sardine Amblygaster sirm during 1995-1997 period. Another 26-36% of the catch composed of other Sardinella species such as Sardinella gibbosa, S. albella, S. sindensis and S. longiceps. Engraulids such as Encrasicholina heteroloba, Stolephorus insularis and Stolephorus indicus and Thryssa spp formed around 3-5% of the catch. The major component of this fishery consisted of Clupeids and Engrauhds and over 65 species ranged between smaller Engraulids to incidental rock fish, sail fish, seer fish, sharks, skates and rays. Around 1.4 to 1.9% of the catch consisted of Chirocentrus dorab, Sphyraenaspp, Scomberomorus spp, Lepturcanthus sp and Megalaspis cordyla. Around 1-11% of the catch consisted of incidentally catches of sharks, rays, skates and sail fish. Another 1.6 to 6% of the catch consisted of Selar crumenophthalamus and Rastrelliger kanagurta. The best fishing season appeared to be from June to October in the west coast and August to December in the south coast. The major components of Amblygaster sirm, Sardinella albella and Sardinella gibbosa were caught within the size ranges of 10.0-22.5 cm, 11.0-13.0 cm and 11.0-15.0 cm respectively. However, smaller sized fish of above species of sizes between 6.9 cm to 9.7 cm total length were incidentally caught in the gill nets operated for small Engraulids with a stretched mesh size of 1.6cm. The overall catch rate for the major fish landing centre at Negombo indicated an increase from 38.5 kg/boat trip during 1984-1990 period to 49.5 kg/boat trip during 1995-1997 period. The catch rate for the dominant species Amblygaster sirm has decreased from 28.17 kg/boat trip during 1983-1990 period to 17.47 kg/boat trip during 1995-1997 period at Negombo. The paper also discusses the changing overall catch rates, change in species abundance and possible management consequences that should be considered.
Resumo:
The report covers the status of: the economic and ecological values of Lake Victoria; priority issues; the vision of the Fisheries Research Component; the objectives of the Fisheries Research Component under LVEMP to generate, package and disseminate scientific knowledge and build capacity.
Resumo:
采用蛋白电泳分析技术研究了来源于我国和越南的猕猴属5个种的蛋白多态性及其遗传分化关系。共分析遗传座位30个。在分析的19只恒河猴中,30个遗传座位有9个座位表现出多态性,多态座位百分比P=0.3,平均等位基因数A=1.4,平均杂合度H=0.1045。此结果表明,恒河猴的遗传多样性在蛋白质水平上是极为丰富的。另外,有10个座位在所分析的猕猴属的5个种中存在2个以上的等位基因,根据基因频率和遗传距离,采用PHYLIP3.5c软件包中的"CONTML"、"NEIGHBOR"和"FITCH",以每一物种作为分类单元,以小懒猴作为外群, 构建了系统树。所得到的3棵系统树均支持恒河猴和食蟹猴聚在一起,表明这两个物种的亲缘关系较为接近,属于一个种组。"ML"树和"FM"树的拓扑结构基本相同,支持将红面猴独立为一个种组,并显示同恒河猴和食蟹猴所聚的一支较为接近;熊猴和藏猴较为接近形成一个种组,聚在树的外部。“NJ”树则将红面猴和熊猴聚为一支,藏猴独立成一支聚在最外部。