992 resultados para Proper


Relevância:

10.00% 10.00%

Publicador:

Resumo:

The mission of NOAA’s National Marine Sanctuary Program (NMSP) is to serve as the trustee for a system of marine protected areas, to conserve, protect, and enhance their biodiversity, ecological integrity, and cultural legacy while facilitating compatible uses. Since 1972, thirteen National Marine Sanctuaries, representing a wide variety of ocean environments, have been established, each with management goals tuned to their unique diversity. Extending from Cape Ann to Cape Cod across the mouth of Massachusetts Bay, Stellwagen Bank National Marine Sanctuary (NMS) encompasses 2,181 square kilometers of highly productive, diverse, and culturally unique Federal waters. As a result of its varied seafloor topography, oceanographic conditions, and high primary productivity, Stellwagen Bank NMS is utilized by diverse assemblages of seabirds, marine mammals, invertebrates, and fish species, as well as containing a number of maritime heritage resources. Furthermore, it is a region of cultural significance, highlighted by the recent discovery of several historic shipwrecks. Officially designated in 1992, Stellwagen Bank became the Nation’s twelfth National Marine Sanctuary in order to protect these and other unique biological, geological, oceanographic, and cultural features of the region. The Stellwagen Bank NMS is in the midst of its first management plan review since designation. The management plan review process, required by law, is designed to evaluate, enhance, and guide the development of future research efforts, education and outreach, and the management approaches used by Sanctuaries. Given the ecological and physical complexity of Stellwagen Bank NMS, burgeoning anthropogenic impacts to the region, and competing human and biological uses, the review process was challenged to assimilate and analyze the wealth of existing scientific knowledge in a framework which could enhance management decision-making. Unquestionably, the Gulf of Maine, Massachusetts Bay, and Stellwagen Bank-proper are extremely well studied systems, and in many regards, the scientific information available greatly exceeds that which is available for other Sanctuaries. However, the propensity of scientific information reinforces the need to utilize a comprehensive analytical approach to synthesize and explore linkages between disparate information on physical, biological, and chemical processes, while identifying topics needing further study. Given this requirement, a partnership was established between NOAA’s National Marine Sanctuary Program (NMSP) and the National Centers for Coastal Ocean Science (NCCOS) so as to leverage existing NOAA technical expertise to assist the Sanctuary in developing additional ecological assessment products which would benefit the management plan review process.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This study assessed the physico-chemical quality of River Ogun, Abeokuta, Ogun state, Southwestern Nigeria. Four locations were chosen spatially along the water course to reflect a consideration of all possible human activities that are capable of changing the quality of river water. The water samples were collected monthly for seven consecutive months (December 2011 – June 2012) at the four sampling stations. pH, air temperature (℃), water temperature (℃), conductivity (µs/cm) and total dissolved solids (mg/L) were conducted in-situ with the use of HANNA Combo pH and EC multi meter Hi 98129 and Mercury-in-glass thermometer while dissolved oxygen (mg/L), nitrate (mg/L), phosphate (mg/L), alkalinity (mg/L) and hardness (mg/L) were determined ex-situ using standard methods. Results showed that dissolved oxygen, hydrogen ion concentration, total hardness and nitrate were above the maximum permissible limit of National Administration for Food, Drugs and Control (NAFDAC), Standard Organization of Nigeria (SON), Federal Environmental Protection Agency (FEPA), United States Environmental Protection Agency (USEPA), European Union (EU) and World Health Organization (WHO) for drinking water during certain months of the study period. Results also showed that water temperature and conductivity were within the permissible limits of all the standards excluding FEPA. However, total dissolved solids and alkalinity were within the permissible limits of all the standards. Adejuwon and Adelakun, (2012) also reported similar findings on Rivers Lala, Yobo and Agodo in Ewekoro local government area of Ogun state, Nigeria. Since most of the parameters measured were above the maximum permissible limits of the national and international standards, it can be concluded that the water is unfit for domestic uses, drinking and aquacultural purposes and therefore needs to be treated if it is to be used at all. The low dissolved oxygen values for the first four months was too low i.e. < 5 mg/L. This is most likely as a result of the amount of effluents discharged into the river. To prevent mass extinction of aquatic organisms due to anoxic conditions, proper regulations should be implemented to reduce the organic load the river receives.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

顽拗性种子在分类上分布广泛。由于顽拗性种子贮藏特性极为特殊,对脱水和低温均十分敏感,易受损伤,所以种子寿命很短,因此在植物种质资源保存领域,顽拗性种子的保存一直被列为重点研究课题,至今仍难以找到顽拗性种子的适宜贮藏条件,或该类种子保存通行的方法,仅推测长期保存顽拗性种子种质资源最有前途的方式是超低温保存,顽拗性种子资源保存是一个世界性难题。 本文试图使用分子运动性预测顽拗性种子离体胚轴的适宜贮藏条件。选用壳斗科植物麻栎种子为实验材料。应用电子顺磁共振波谱仪和自旋标记技术,以硝基氧探针CP为标记物,检测到室温下麻栎种子离体胚轴脱水过程中分子运动性的变化。含水量0.7 g H2O/g DW至0.64 g H2O/g DW范围是细胞质粘度的转折区域,低于这个含水量区域,细胞质粘度骤然上升,推测这个区域是室温下保存离体胚轴的适宜含水量下限。 通过变温电子顺磁测定,找到离体胚轴含水量在0.43 g H2O/g DW至1.02 g H2O/g DW范围内,分子运动性的临界温度和玻璃态相变温度所在区间。根据分子运动性随温度变化规律,预测含水量为0.69 g H2O/g DW的麻栎种子离体胚轴适宜贮藏温度约为-50 ℃。 根据EPR实验结果,将胚轴脱水,并根据实验条件选择不同温度进行低温贮藏验证实验,应用颜色观测法和TTC存活力鉴定法,初步验证分子运动性理论可以应用在顽拗性种子离体胚轴的低温贮藏研究中。 本研究说明顽拗性种子资源的保存有可能通过离体胚轴的低温贮藏实现,用分子运动性预测低温贮藏的适宜条件,很可能为上述问题的解决提供了有效的技术参数。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The culture of Chanos chanos to marketable size within a three months period, is described. Procedures involved include phased manuring coupled with proper water management to keep up enhanced primary productivity. Results show that, under monoculture, with low-input technology it is possible to produce 3,000 kg fish per hectare per year.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The fishery resources of India are extensive. The demand for fish for domestic consumption will be at least 10 million by 2000 AD. With proper planning and management, fish production from inland, brackishwater and marine sources can be increased to 5 million tonnes, 1 million tonne and 4 million tonnes respectively. But the increase in the last 37 years is approximately equals 2.1 million tonnes over the base level of 1950. If the present trend is continued, the expected fish production will be approximately equals 6 million tonnes by 2000 AD, and hence, only approximately equals 60% of the domestic demand can be met.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Various problems associated with the quality of the fishery products like spoilage, discolouration, microbiological problems, etc., are outlined. The reasons and remedial measures are discussed. The importance of proper handling, processing and hygiene is stressed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Maharashtra stands third in fish production in India, with an estimated annual landings of 3.32 lakhs tonnes (1986-87). About 45% of the fishermen are directly involved in fishing. Mechanisation has boosted fish production resulting in gainful employment and higher incomes to fishermen. However, traditional fishermen along Thane creek and who entirely depend on fishing for their livelihood are comparatively poor due to their dependence on subsistence fishing and reduction of fish stock due to pollution of the creek. Conservation of the resources, proper monitoring of pollution and financial assistance and guidance will help the fishermen improve their living conditions.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

草地退化不仅仅是今天中国才发生的事情。历史上曾经发生“黑尘暴”的美国North Dakota州,现在仍然有62.7%土地被用作耕作,林地所占面积仅仅占1%。私有制和种植业较畜牧业的高的利润率,是该州种植业比重高于畜牧业的重要原因。草原保护项目(CRP)得到了美国政府财政的大力支持, 在North Dakota州采用了以草地恢复为主的措施。美国发达的教育体系带来的高流动率,使得North Dakota州自30年代后居住人口稳定在60-70万成为可能,从而避免了我国出现的草原地区不断增加的人口压力。由此可见:草地作为重要的自然资源,不可能完全保护起来;没有其他配套措施,私有制可能会带来新一轮垦殖;草地畜牧业仍然是畜牧业的重要组成部分,畜牧业发展需要结合种植业尤其需要与饲料生产相结合。 依据生态系统服务的理念,首次发展了生态系统服务指数(ESI),试图通过对生态系统服务功能的综合考虑,提出科学的适宜放牧率的评价方法。本文利用美国北达科他州立大学中部草原研究站17年长期放牧试验数据,选取植物多样性Shannon-Wiener指数、地上净初级生产力、土壤表层含水量和单位面积家畜增重等四个指标,通过对不同指标分别赋予不同的权重,计算不同管理目标下ESI及其稳定性,并对单目标管理与多目标管理进行了比较研究。结果表明,对于北美混合普列里(Prairie)草地,围封不利用或建立自然保护区,虽然生态系统比较稳定,但既不能有效的提高植物多样性、初级生产力和土壤水分含量等生态功能,又没有畜产品产出;而在重牧或极重牧处理下虽然获得了较大的畜产品生产,但导致了草地生态系统的退化和较大的系统不稳定性。因此,这两种管理方式在实践中都是不可取的。应用生态系统服务指数综合考虑,认为应该权衡各项生态功能和生产功能,此时轻牧或中牧是最适宜的。因此,ESI的建立避免了单项指标的评价偏差,使得适宜放牧率的确定更加合理。 利用前面构建的多目标权重评价体系,结合内蒙古草原生态系统定位站放牧试验样地的数据,探讨了锡林郭勒盟定位站附近的适宜放牧率为2.67羊/ha,低于单目标条件下的每公顷绵羊4羊/ha。同时在经济学和生态系统系统服务理论的基础上,依据谢高地等人(2001年)的研究,并提出了环境税和生态补偿的标准,分别是每公顷15元和90元。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The magnitude and disposition of the inland prawn fisheries resources of the country have been described. The lack of adequate knowledge of the capture fisheries resources has been pointed out and the necessity for an organised survey of the resources and research to formulate measures for their proper management emphasised. The existing methods of prawn farming in the country have been described and the need for research for maximising yields from culture fisheries of prawn has been highlighted. Measures for immediate development of prawn fisheries of the country have also been discussed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The proper matching of the pull exerted by a trawler and the size of trawl is important for maximizing the catching efficiency. The available pull is more dependent on the propeller and its working conditions than the installed engine power. The normal practice is to directly connect net size to the installed power in the boat by formulae without reference to the prope1ler dimensions or the available trawling pull and this is not adequate to find out the optimum combination. By the method outlined in this paper, the accurate calculation of trawling pull is possible by taking into account only the propeller diameter, pitch and r. p. m. The predictions by the method are compared for trawlers with powers between 30 and 60 hp and agreement is found to be within + 5%. The power absorbed by the propeller in trawling condition can also be calculated by this method for checking whether the engine is being overloaded.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Difficulties are very often encountered in selecting proper material for making stern bearings for fishing boats. Conventional materials such as white metal, bronze etc. wear out too fast also causing considerable wear to the propeller shaft. Lignum-vitae, a natural wood commonly used for this purpose, is not available on a commercial scale in our country. Results of trials carried out to find out suitable substitutes for lignum-vitae from among indigenous timbers are presented in this paper.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

India has a long coast line of about 4,800 km along which fish landing centers are scattered. Fish catches are showing an upward trend consequent on rapid mechanization of fishing crafts. Economic utilization of the landed fish is an essential prerequisite for the proper development of Indian fishing and fish processing industries.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A modified method for the preparation of laminated Bombay duck is presented. Investigation was carried out to find out an effective chemical to control the discoloration of dried laminated Bombay duck. Among various chemicals tried, NDGA and BHT were found to have considerably retarded the discoloration and extended the storage life of the product. Attempt was also made to suggest the optimum humidity level for the proper storage of the commercially dried fish. It was found that a level of about 65% R. H. provided maximum storage life to commercial product.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The paper gives an account of the types of blackening associated with canned prawn in brine and their control. It was found that blackening caused by iron sulphide could be controlled by maintaining proper titratable acidity of fill brine in cans. The paper also elaborates on the factors responsible for or governing this critical titratable acidity. In regard to copper sulphide blackening, control was found to be difficult by maintaining the acidity or by additives such as EDTA when the copper content in the material went above the critical level.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Tripura is a densely populated small state with meagre water resources. 47.51% of the population is constituted by socio-economically backward, illiterate, orthodox, tribal and scheduled castes. Some of them are nomad and a majority of the rest of the population is refugees from Bangladesh, but almost 100% is fish eater. Settlement of tribes in villages, provision of nutritious food and employment therefore calls for proper utilization of every resource they have. The State is poor in water resources but recently has created 21,636.23 ha of new water area. Tripura is rich in pig population, besides poultry birds. Paddy is the main crop cultivated in arable lands. An integration of livestock raising and land based agriculture with pisciculture practices around mini barrages will help in solving the problems to a great extent. The paper is an attempt to outline the prospects of integration of aquaculture with animal husbandry and land based crop culture in Tripura State.