141 resultados para western ridge
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 results are presented of a study of milkfish fry occurrence in the Philippines, namely at Magaba and at Tubog. There were 2 peaks of fry occurrence in the latter, one in May and another in October, whereas only one peak occurred in the former in May. The possible influence on light intensity on the fry seasons is examined.
Resumo:
This study was done in Shahid Kiani Marine Aquaculture Development Center, Choebde, Abadan in order to evaluate the effects of Pediiococcus acidilactici, Lactococcus lactis and vitamin C on growth performance, survival, enzymatic activities and immune responses of L. vannamei during three months. Treatments were included control group, Pediiococcus and Lactococcus treatments which fed with diet containing 1×10P9P cfu gP_1P bacteria and vitamin C. At the end of the experiment, the growth factors, immune parameters, digestive enzymes, intestinal, histology of intestine, carcasses and microbial flora (bacterial total count and lactic acid count) were evaluated. The results indicated that administration of lactobacillus had significant effects on the growth factors as the highest weight, increase specific growth rate, relative growth rate, feed conversion ratio and protein efficiency in the shrimps received pediococcus and then Lactococcus (P<0.05). The best immune function was also observed in the shrimps fed by probiotics, so that proteins and hemoglobin̛ hemolymph, phenoloxidase activity and challenged with V. parahaemolyticus showed a statistical difference comparing to the control group and the group received vitamin C (P<0.05). Some digestive enzymes, in pediococcus treatment showed a significant increase when compared to other treatments (P<0.05). Significant changes in bacterial intestinal flora were observed in probiotic groups compared with control and vitamin C groups (P < 0.05). Histological results showed the positive effects of probiotics in the gut (P < 0.05). While these supplements cannot caused to significant impacts on the shrimp carcass composition (P ˃ 0.05). As a result pediococcus group had the best performance among treatments.
Resumo:
There is increasing awareness that integrating gender into development frameworks is critical for effective implementation of development strategies. In working to alleviate rural poverty, the CGIAR Research Program on Aquatic Agricultural Systems (AAS) recognizes that “business as usual” gender integration approaches will not deliver lasting and widespread improvements in agricultural productivity, poverty reduction and food security. In response, AAS operationalized a gender transformative approach. The approach is informed by conceptual frameworks that explicitly recognize the potent influence of social relations on creating and perpetuating gender inequalities. In this way, AAS aims to address the underlying causes of rural poverty and gender inequality in Zambia’s Barotse Floodplain, where people rely extensively on riverine and wetland ecosystems for food and livelihood security. A central question guiding the research program is “How do social norms and gendered power relations influence agricultural development outcomes?” The findings presented in this report provide insights that help answer this question. The report presents a review of literature relevant to livelihoods, ecosystem services, and gender and social relations in Zambia, with a specific focus on Western Province, where AAS is currently implemented. It also presents a synthesis of findings of a social and gender analysis conducted in 2013 in 10 focal communities situated in and around the Barotse Floodplain.
Resumo:
In May, 1971, Lake Mahega had pronounced mesothermy (40.W C at one metre). Solar heating of a bloom of baeteria and the blue-green alga, Synechococcus bacillaris Butch., probably caused the high temperature. A total ionic concentration gradient increasing from 192,600 mg 1itre-1 at the surface to 415,200 mg•litre- 1 at three metres stabilized the thermally inverted water. Nearly equal amounts of chloride and sulphate accounted for about 90% of the anionic composition. Sodium was the major cation. Crystals or the triple salt, northupite (Na2 CO3. MgCO3. NaCl) and of thenardite (Na2SO4) were mixed with the surface sediment. We believe it is possible that primary northupite depnsition is occurring. Lake Mahega is also the first mesothermic, sulphato-chloride lake reported for East Africa.
Resumo:
The small brachyuran family Raninidae Dana is represented in the Indo-West Pacific region by eight genera, with only some twenty species. One of the least known genera is Notopoides, which contains only a single species. This genus was first described by Henderson (1888) on the basis of material collected by H.M.S. "Challenger" from the Kei Islands, in the Banda sea off Indonesia. There have been no subsequent reports of this species in the ninety seven years since its original discovery. During the course of the study of the benthic fauna off the coast of East Africa, the Fisheries Research Vessel "Manihine" obtained five specimens of this rare species. These new records, collected during a short period of time, indicate that the species is probably not uncommon in this region, which also represents a great increase in its known geographical range. Specimens have been deposited in the collections of the National Museum, Nairobi, the Rijksmuseum van Natuurlijke Historie, Leiden, and the National Museum, Singapore: Catalogue numbers are crust. 1092 ; Crust. D. 28567; NMS. 1972.8.4.1, male of 35x26 respectively.