949 resultados para Small Scale Industries


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This handbook provides detailed information for a wide range of legal instruments relevant to fisheries and fishworkers. It covers 114 legal instruments, categorized into the following seven themes: Theme I. Human Rights, Food Security, Women and Development. Theme II. Environment and Sustainable Development. Theme III. Oceans and Fisheries Management. Theme IV. Environmental Pollution Theme V. Fishing Vessels and Safety at Sea Theme VI. Labour Theme VII. Trade The handbook also includes the working of the instruments (decision-making bodies, monitoring and implementation agencies, periodicity of meetings, rules for participation in meetings of the decision-making bodies and implementation agencies for States and non-governmental organizations), regional instrument and agencies. Apart from being a ready reckoner to the instruments, it highlights the important sections of relevance to fisheries or small-scale fisheries and fishworkers. The companion CD-ROM provides the full texts of the instruments in a searchable database. The handbook will be useful for fishworker and non-governmental organizations, and also for researchers and others interested in fisheries issues.

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The Common Octopus, Octopus vulgaris, is an r-selected mollusk found off the coast of North Carolina that interests commercial fishermen because of its market value and the cost-effectiveness of unbaited pots that can catch it. This study sought to: 1) determine those gear and environmental factors that influenced catch rates of octopi, and 2) evaluate the feasibility of small-scale commercial operations for this species. Pots were fished from August 2010 through September 2011 set in strings over hard and sandy bottom in waters from 18 to 30 m deep in Onslow Bay, N.C. Three pot types were fished in each string; octopus pots with- and without lids, and conch pots. Proportional catch was modeled as a function of gear design and environmental factors (location, soak time, bottom type, and sea surface water temperature) using binomially distributed generalized linear models (GLM’s); parsimony of each GLM was assessed with Akaike Information Criteria (AIC). A total of 229 octopi were caught throughout the study. Pots with lids, pots without lids, and conch pots caught an average of 0.15, 0.17, and 0.11 octopi, respectively, with high variability in catch rates for each pot type. The GLM that best fit the data described proportional catch as a function of sea surface temperature, soak time, and station; greatest proportional catches occurred over short soak times, warmest temperatures, and less well known reef areas. Due to operating expenses (fuel, crew time, and maintenance), low catch rates of octopi, and high gear loss, a directed fishery for this species is not economically feasible at the catch rates found in this study. The model fitting to determine factors most influential on catch rates should help fishermen determine seasons and gear soak times that are likely to maximize catch rates. Potting for octopi may be commercially practical as a supplemental activity when targeting demersal fish species that are found in similar habitats and depth ranges in coastal waters off North Carolina.

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What Are ~umulat iveE ffects? Coastal managers now recognize that many of the most serious resource degradation problems have built up gradually as the combined outcome of numerous actions and choices which alone may have had relatively minor impacts. For example, alteration of essential habitat through wetland loss, degradation of water quality from nonpoint source pollution, and changes in salinity of estuarine waters from water diversion projects can be attributed to numerous small actions and choices. These incremental losses have broad spatial and temporal dimensions, resulting in the gradual alteration of structure and functioning of biophysical systems. In the environmental management field, the term "cumulative effects" is generally used to describe this phenomenon of changes in the environment that result from numerous, small-scale alterations.

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From the 1940s until 2003, portions of the island of Vieques, a municipality within the Commonwealth of Puerto Rico, were used by the US Navy as a base and training facility, resulting in development and zoning history that differ in comparison to other Caribbean islands. The majority of former Navy lands are now under the jurisdiction of the Department of the Interior’s Fish and Wildlife Service as a National Wildlife Refuge, while a smaller percentage of land was transferred to the Vieques municipality and the Puerto Rico Conservation Trust. An analysis of the distribution and status of the marine resources is timely in light of the recent land transfer, increases in development and tourism, and potential changes in marine zoning around the island. To meet this need, NOAA’s Biogeography Branch, in cooperation with the Office of Response and Restoration and other local and regional partners, conducted Part I of an ecological characterization to integrate historical data and research into a synthesis report. The overall objective of this report is to provide resource managers and residents a comprehensive characterization of the marine resources of Vieques to support research, monitoring, and management. For example, knowledge of the spatial distribution of physical features, habitats, and biological communities is necessary to make an informed decision of the establishment and placement of a marine protected area (MPA). The report is divided into chapters based on the physical environment (e.g., climate, geology, bathymetry), habitat types (e.g., reefs and hardbottom, seagrasses, mangroves) and major faunal groups (e.g. fish, turtles, birds). Each section includes five subsections: an overview, description of the relevant literature, methods of analysis, information on the distribution, status and trends of the particular resource, and a discussion of ecological linkages with other components of the Vieques marine ecosystem and surrounding environment. The physical environment of Vieques is similar to other islands within the Greater Antilles chain, with some distinctions. The warm, tropical climate of Vieques, mediated by the northeasterly trade winds, is characterized by a dry season (December-April) and a rainy season (May-November), the latter of which is characterized by the occasional passage of tropical cyclones. Compared to mainland Puerto Rico, Vieques is characterized by lower elevation, less annual precipitation, and higher average temperatures. The amount of annual precipitation also varies spatially within Vieques, with the western portion of the island receiving higher amounts of rainfall than further east. While the North Equatorial Current dominates the circulation pattern in the Greater Antilles region, small scale current patterns specific to Vieques are not as well characterized. These physical processes are important factors mitigating the distribution and composition of marine benthic habitats around Vieques. In general, the topography of Vieques is characterized by rolling hills. Mt. Pirata, the tallest point at 301 m, is located near the southwest coast. In the absence of island wide sedimentation measurements, information on land cover, slope, precipitation, and soil type were used to estimate relative erosion potential and sediment delivery for each watershed. While slope and precipitation amount are the primary driving factors controlling runoff, land use practices such as urban development, military activity, road construction, and agriculture can increase the delivery of pollution and sediments to coastal waters. Due to the recent land transfer, increased development and tourism is expected, which may result in changes in the input of sediments to the coastal environment.

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The Republic of Kiribati is a vast South Pacific island group with one of the largest exclusive economic zones (EEZs) in the world. Kiribati waters support a wealth of marine fisheries activities. These activities occur in oceanic, coastal and inshore environments and range from large, foreign, industrial-scale oceanic fishing operations to small-scale, domestic, inshore subsistence fisheries, aquaculture and recreational fisheries. Kiribati has developed a framework of domestic and international governance arrangements that are designed to sustainably manage its wealth of marine resources. The report provides background information for fisheries projects in Kiribati that aim to build food security, improve artisanal livelihoods and strengthen community engagement in fisheries governance. It provides information on the current status of Kiribati fishery resources (oceanic and coastal), their current governance and future challenges. Fish and fisher alike pay little heed to maritime boundaries and bureaucratic distinctions. This report covers both sides of the oceanic/coastal boundary because of the I-Kiribati communities’ interest in oceanic fisheries such as tuna and their heavy dependence on its fisheries resources for food security and economic development. The report focuses on two potential pilot sites for community-based fisheries management projects: North Tarawa and Butaritari.

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The small-scale fishery is a traditional activity and enrolled in social and cultural practices of the coastal communities and some places of the inland waters of Mozambique. Scope for development, major constraints in the small-scale fisheries and best practices are examined.

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采用位置指数、分异指数、结构复杂性指数、Shannon-Wiener多样性指数以及Ripley的K-方程,探讨了华南海岸英罗港红树植物木榄种群的分布格局、胸围和树高分异以及冠层结构方面的空间异质性。结果表明,多数木榄种群呈现随机分布,其个体胸围和树高的分异程度较低;而少数木榄种群呈现集群分布,其个体胸围和树高的分异程度明显。采用地理信息系统对木榄种群冠层和空隙斑块进行多种水平和垂直尺度的分析,冠层与空隙斑块之间的镶嵌格局因种群而异,这种格局可基于树冠投影用Shannon-Wiener多样性指数进行定量描述。冠层结构的空问异质性随空间尺度而变化,但这种变化在一定尺度范围内保持相对的稳定。这一尺度范围可作为木榄红树林更新或生态管理单位的参考尺度。 采用多重分形理论和方法对华南海岸北海红树林区红树植物白骨壤幼苗种群的分布格局进行了分析。结果表明,白骨壤幼苗种群的分布格局具有多标量和多重分形行为。随着q值由-2增加到4,Dq值介于1.078-1.997,f(a)值介于0.402-1.678,a(q)值介于0.909-2.480。多重分形的参数值与幼苗种群的集聚强度密切相关。差值(D。-D1)和[f(-1) –D]。是度量格局空间异质性程度的有效指数。海洋水文周期性规律、不同面积大小的裸地、树冠的阻拦作用等是制约白骨壤幼苗种群多重分形格局形成的主要因子。 采用地统计学理论和方法,对北京东灵山落叶松和胡桃楸针阔混交林下的克隆植物绢毛匍匐委陵菜分株种群的统计变量和土壤变量的空间格局进行了分析和比较。结果表明,绢毛匍匐委陵菜分株种群各器官生物量以及分株数和叶数的空间格局具有较高程度的异质性。总生物量以及茎、叶和根生物量的半方差函数曲线为指数模型,叶柄生物量、分株数和叶数的为球状模型,叶片生物量的为线性无基台值模型,而匍匐茎生物量的为纯块金效应模型。除叶片和匍匐茎的生物量外,其它器官生物量以及分株数和叶数由空间自相关引起的空间异质性.SHA主要表现在120-3 50cm的尺度范围内,SHA占总空间异质性的比例在50%以上。生境中,各种土壤变量的空间格局也具有较高程度的异质性。土壤含水量、NO3-、NH4+、有机质、全磷和PO4(3-)的半方差函数曲线为球状模型,而全氮、K+和pH的为指数模型。土壤变量由空间自相关引起的空间异质性SHA主要表现在8-lOOcm的尺度范围内,SHA占总空间异质性的比例在68%以上。绢毛匍匐委陵菜分株种群空间格局的自相关尺度显著大于其生境中土壤变量空间格局的自相关尺度,表明绢毛匍匐委陵菜通过匍匐茎相互联结的克隆分株种群对异质性土壤资源表现出较大的缓冲能力。绢毛匍匐委陵菜分株数的空间格局与土壤的含水量和全氮空间格局之间在几乎所有尺度上的相关性都不显著,但与其它土壤变量空间格局之间都存在不同程度的相关性,其中与NH4+、pH、PO4(3-)和全磷空间格局之间的相关性尺度范围较为明显和较大。通过分株数、叶数和生物量分配的可塑性变化,绢毛匍匐委陵菜分株种群的空间格局与土壤资源的空间格局之间产生相互联系,并随空间尺度的变化会发生改变。

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植物种间作用是决定物种分布、种群动态、群落演变和生态系统功能的重要因子。长期以来,相关研究集中在竞争作用上。然而自1990年代以来,易化作用逐渐受到重视,被认为是植物群落中物种共存的主要推动力,尤其是在极端和受到干扰的环境中。很多研究都揭示出植物对其他特定的物种产生直接或间接的正向的作用。护卫植物主要通过两种机制对临近的物种产生正向作用,即对恶劣的自然环境的改善和对高强度干扰的阻止和减轻。灌木在很多条件下能够成为护卫植物,影响种群的分布、群落的多样性和生态系统的功能。 中国西南部的青藏高原的牧场上,非生物的环境胁迫(比如生长季短暂、辐射强度大和极端温度等)和生物的干扰作用(比如过度放牧等)都很强。有文献表明,随着过度放牧现象的加重和草地的不断退化,灌木的分布有逐渐扩大的趋势。针对灌木对过度放牧草地上小尺度植被格局的影响,我们在若尔盖地区展开了以下两方面的研究。 为了研究不同种类灌木的影响,我们在若尔盖高原上选择了既具有恶劣的自然环境又遭受过度放牧压力的草地,对三种灌木内外的相同大小面积上小尺度范围内的植被进行调查。三种灌木分别是高山绣线菊、窄叶鲜卑花和金露梅,它们在形态结构、高度和可食性上都存在差异。在不考虑灌木种类的基础上,我们发现物种丰度、总盖度、开花的物种数和花序数都是灌木内部高于外部,而均匀度则恰好相反,是外部要高于内部,香农多样性指数内外没有明显的差异。金露梅灌丛中内外物种丰度和均匀度的差异要明显高于窄叶鲜卑花,但是总盖度、开花的物种数和花序数的差异不随着灌木种类的不同而有明显的差异。大多数的物种(占总物种数的47-85%)并没有因为灌木的存在而在内外出现的频数上表现出差异,而相当一部分物种(占总物种数的13-39%)在灌木外部的频率要高,仅仅有很少的物种(占总物种数的3-13%)因为灌木的存在而受益,内部的频数要高于外部。这种对某些物种的保护作用没有表现在群落水平上,即提高群落的物种丰富度和多样性,因为同时发生的灌木和其他植物的竞争作用也会限制以致排除冠层下面某些物种的存在。灌木的可食性和形态结构(比如盖度、高度、冠层的紧实度等)能对它们跟其他植物的相互之间净作用的类型和强度产生影响。不同的灌木能保护不同种类、不同数量的植物,表明易化作用是物种特异性的,跟护卫植物有关,也跟受益者有关。通过植被的排序,金露梅和高山绣线菊内外的植被得到了很明显的分离,而窄叶鲜卑花的则没有。总体上来说,灌木的存在确实能够通过提高出现或开花的频率,保护了某些对放牧比较敏感的物种,而且这种易化作用是物种特异性的。内外植被的差异在放牧压力最大的金露梅灌丛中最大,表明过度放牧导致的大尺度的植被状况对于小尺度上灌丛内外的植被的差异所起的作用比灌木种类的作用更大。 为了研究同种灌木不同的分布类型对植被格局的影响,选择金露梅作为目标灌木。金露梅是当地常见灌木,有的植株孤立存在,有的则是很多株联合形成比较大的斑块。我们选择金露梅形成的斑块中央、外沿金露梅植株内部、外围和孤立的金露梅植株内部、外部五个位置,并在小尺度上进行了植被调查和比较,发现金露梅的存在确实保护了一些物种,但是种类有限,反而是大部分的物种在外部的频数要高与内部;从群落水平来看,金露梅冠层下的植被从丰富度、多样性上来讲并没有超过外部,仅仅是具有更高的均匀度和同质性;生殖方面的结果也是类似的,而且大部分物种跟其分布呈现出基本类似的格局。金露梅斑块的存在和自然围栏的产生没有起到很明显的保护作用,并没有使得斑块中央植被的丰富度、多样性、均匀度提高,而仅仅是提高了植物的长势(表现为具有较高的总盖度等);在物种水平,没有发现什么特异种的存在,仅仅发现能够促进一些物种在内部的生长或开花,而且比例很低。在这种效应的影响下,斑块边缘的金露梅相对于孤立的金露梅而言,也没有表现出更好的保护植被的能力。几乎所有的群落水平的指标都仅仅是受到灌木内外这个因素的影响,而两种分布格局(即:在斑块边缘和孤立存在)的影响是微乎其微的。植被排序的结果也充分证明了这一点,灌木内外的植被被明显的分离开来,而不同灌木中相应位置的植被则是混杂在一起。并且在物种水平上,除了极个别的物种之外,绝大部分物种内外的差异是是一致的,没有受到灌木分布格局的影响。即使个别物种具有不同的格局,也没有证据表明是受到了斑块中央植被的影响而产生的。

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Three species of bacteria, 8 species of fungi and 3 species of VAM-fungi were isolated from the soil substrata supporting Avicennia marina which comprises the majority of mangrove vegetation along the Karachi coast. The species abundances for fungi and bacteria were greater at one site (Sandspit) supporting healthy mangrove growth with soil pH 7.8, EC 16.2mmhos/cm², TSS 2.57% and available phosphorus 0.008% than at the other site (Korangi creek) with stunted growth of mangrove where the soil samples showed pH 7.9, EC 18.8mmhos/cm², TSS 1.45% and available phosphorus 0.001%. Symbiotic association by vasicular-arbuscular mycorrhizal (VAM) fungi in the roots of mangrove plants was also observed on a small scale at Korangi creek where the substratum was undergoing microbial degradation.

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Sintered boron carbide is very hard, and can be an attractive material for wear-resistant components in critical applications. Previous studies of the erosion of less hard ceramics have shown that their wear resistance depends on the nature of the abrasive particles. Erosion tests were performed on a sintered boron carbide ceramic with silica, alumina and silicon carbide erodents. The different erodents caused different mechanisms of erosion, either by lateral cracking or small-scale chipping; the relative values of the hardness of the erodent and the target governed the operative mechanism. The small-scale chipping mechanism led to erosion rates typically an order of magnitude lower than the lateral fracture mechanism. The velocity exponents for erosion in the systems tested were similar to those seen in other work, except that measured with the 125 to 150 μm silica erodent. With this erodent the exponent was initially high, then decreased sharply with increasing velocity and became negative. It was proposed that this was due to deformation and fragmentation of the erodent particles. In the erosion testing of ceramics, the operative erosion mechanism is important. Care must be taken to ensure that the same mechanism is observed in laboratory testing as that which would be seen under service conditions, where the most common erodent is silica.

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This commodity and product identification research was undertaken in the context of the CGIAR Research Program on Aquatic Agricultural Systems (AAS). AAS seeks to reduce poverty and improve food security for the millions of small-scale fishers and farmers who depend on the world’s floodplains, deltas and coasts. The objective of this research is to strengthen the capacity of AAS to undertake value chain studies with high potential impact on smallholders. The capacity-building aspect of this research was focused on the process of commodity and product identification for value chain analysis. Its scope was limited to fish and other aquatic animals and products in the Tonle Sap area identified for AAS intervention. The result of the identification process was the selection of a number of commodities and products that were deemed to involve a high number of smallholders along the value chain and that have high market development potential.

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PD6493:1991 fracture assessment have been performed for a range of large-scale fracture mechanics tests conducted at TWI in the past. These tests cover several material groups, including pressure vessel steels, pipeline steels, stainless steels and aluminium alloys, including parent material and weldments. Ninety-two wide plate and pressure vessel tests have been assessed, following Levels 1, 2 and 3 PD6493:1991 procedures. In total, over 400 assessments have been performed, examining many features of the fracture assessment procedure including toughness input, proof testing, residual stress assumptions and stress state (tension, bending and biaxial). In all cases the large scale tests have been assessed as one would actual structures: i.e., based on lower bound toughness values obtained from small scale fracture toughness specimens.

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This report on the “Sub-regional Dialogue on Labour, Migration and Fisheries Management”, held at Chulalongkorn University, Bangkok, Thailand, from 11 to 13 December 2013, highlights the issue of migrant labour on board fishing vessels and the problems migrant workers face in their workaday lives. This report will be useful for students, researchers, activists and anyone else interested in matters related to fisheries and small-scale fishing communities.

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Cyclic loading of a plane strain mode I crack under small scale yielding is analyzed using discrete dislocation dynamics. The dislocations are all of edge character, and are modeled as line singularities in an elastic solid. At each stage of loading, superposition is used to represent the solution in terms of solutions for edge dislocations in a half-space and a non-singular complementary solution that enforces the boundary conditions, which is obtained from a linear elastic, finite element solution. The lattice resistance to dislocation motion, dislocation nucleation, dislocation interaction with obstacles and dislocation annihilation are incorporated into the formulation through a set of constitutive rules. An irreversible relation between the opening traction and the displacement jump across a cohesive surface ahead of the initial crack tip is also specified, which permits crack growth to emerge naturally. It is found that crack growth can occur under cyclic loading conditions even when the peak stress intensity factor is smaller than the stress intensity required for crack growth under monotonic loading conditions; however below a certain threshold value of ΔKI no crack growth was seen.

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Small scale yielding around a mode I crack is analysed using polycrystalline discrete dislocation plasticity. Plane strain analyses are carried out with the dislocations all of edge character and modelled as line singularities in a linear elastic material. The lattice resistance to dislocation motion, nucleation, interaction with obstacles and annihilation are incorporated through a set of constitutive rules. Grain boundaries are modelled as impenetrable to dislocations. The polycrystalline material is taken to consist of two types of square grains, one of which has a bcc-like orientation and the other an fcc-like orientation. For both orientations there are three active slip systems. Alternating rows, alternating columns and a checker-board-like arrangement of the grains is used to construct the polycrystalline materials. Consistent with the increasing yield strength of the polycrystalline material with decreasing grain size, the calculations predict a decrease in both the plastic zone size and the crack-tip opening displacement for a given applied mode I stress intensity factor. Furthermore, slip-band and kink-band formation is inhibited by all grain arrangements and, with decreasing grain size, the stress and strain distributions more closely resemble the HRR fields with the crack-tip opening approximately inversely proportional to the yield strength of the polycrystalline materials. The calculations predict a reduction in fracture toughness with decreasing grain size associated with the grain boundaries acting as effective barriers to dislocation motion.