993 resultados para Freshwater lake


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This study was aimed to analyze the annual reproductive cycle of the freshwater crab Paratelphusa spinigera (Wood Mason, 1871). P. spinigera breeds only once in a year; hence, it is a monovoltine species. Gonad maturation, changes in abdomen shape, size and female maturity index (FMI) marked the onset of sexual maturity of female P. spinigera. The occurrence of berried females marked the onset of breeding season. The fecundity of P. spinigera ranged from 533 to 1306 in number, with an average of 699.11 ± 217.38. The correlation of fecundity with carapace width and body weight was also found to be positively significant (r = 0. 780 and 0.933, respectively). The eggs were carried on the pleopods and nurtured for approximately 30-35 days, until the eggs hatch, showing perfect maternal care. The FMI values ranging between 0.70 and 0.80 represented immature stage of gonadal development. When the FMI ranged from 0.91 to 1.00, all stages of gonadal development, i.e. developing, maturing and mature stages were observed. The females with fully ripe ovary had FMI values greater than 1.00.

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A novel Gram-positive, motile, rod-shaped bacterium isolated from a saline soil in China was characterized by a polyphasic taxonomic approach. The strain, designated YC1(T), was halotolerant [tolerating up to 15 % (w/v) NaCl] and alkaliphilic (growing at

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It is a common knowledge that illegal fishing which includes use of wrong gears, explosives, excessive exploitation of choice stocks, enhancement and stocking of water body and pollution has devastating effects on the critical biomass of fish biodiversity and livelihood activities associated with fishing. Efforts worldwide to arrest these menace are significant because it has been found that illegal fishing has made fishing non sustainable, resulted in poor fishermen catches, and exacerbated the use of illegal gears in an effort to a must catch. Conflict between fisher folk and policies has continued to generate different strategies in the control of illegal fishing. Some of these strategies at regional and National levels include creation and implementation of fisheries laws, fishing edicts, code of conduct for responsible fisheries, policing of inland water bodies, capacity building and capability through training of fishermen, creating necessary awareness, arrest and punishment of offenders. There are also other initiative on conservation and management of freshwater ecosystems which have interrelation with illegal fishing. This paper examines efforts in promoting and boosting the fisheries of Lake Kainji, through creating necessary awareness, campaign visits, radio programmes, gear control, reward systems, integration and diversification of livelihood activities, community based management and policing. It further analyses what is working, problems, and prospect of fisheries laws, the need to integrate factors of political policies, other global initiative on water management for people and nature. Recommendations on strategies including protection of fishing grounds, establishment of catch data base, integration of other intervention as alternative source of income to enhance livelihood, reduce fishing pressure, and capacity building of fisher folks, development of rules and regulations that is community based are highlighted.