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The nature of the animal taxa that are the most probable candidates for an intensive, commercial aquatic animal husbandry industry is considered. A characterization is presented of those biological criteria that lend the species the necessary physiological and genetic malleability to be adapted and molded into a domesticated race. The animal cultivated must be amenable to intensive management in high-density confinements such as those now being engineered for high-yield aquaculture. Atributes considered are discussed in the context of the various aquacultural ecosystems in which the specific biotype is expected to achieve satisfactory growth and survival. Correlative with bionomic criteria, economic requirements are posed and evaluated in an effort to define a socially and financially profitable agribusiness system. Investment requirements and operating costs are considered in terms of expected returns. However, since production alone is insufficient to sustain an enterprise — i.e. the product must be sold — production costs must be judged against market values. Therefore, ultimate use or consumer acceptance criteria are incorporated into the list of essential requirements for a candidate species for aquafarming. 相似文献
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Remedies for pseudoreplication 总被引：1，自引：0，他引：1
Pseudoreplication is the failure of a statistical analysis to properly incorporate the true structure of randomness present in the data. It has been well documented and studied in the ecological literature but has received little attention in the fisheries literature. Avoiding pseudoreplication in analyses of fisheries data can be difficult due to the complexity of the statistical procedures required. However, recent developments in statistical methodology are decreasing the extent to which pseudoreplication has to be tolerated. Seven examples are given here, beginning with simple design-based remedies and progressing to more challenging examples including the model-based remedies of mixed-effects modelling, generalized linear mixed models, state-space models, and geostatistics. 相似文献
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Coastal Social–Ecological Systems (SESs) are subject to several stresses, including climate change, that challenge fisheries and natural resource management. Fishers are front‐line observers of changes occurring both on the coast and in the sea and are among the first people to be affected by these changes. In this study, we perform a meta‐analysis of observations and adaptations to climate change by subsistence‐oriented coastal fishers extracted from a global review of peer‐reviewed and grey literature. Fishers' observations compiled from across the globe indicate increased temperatures and changes in weather patterns, as well as coastal erosion, sea level rise and shifts in species range and behaviours. Coastal areas offer a wide array of resources for diversifying livelihoods, but climate change is reducing these options. Specifically, climate change could reduce the resilience of fishers' communities, limiting options for diversification or forcing fishers to abandon their houses or villages. 相似文献
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E.W. Tollner Daniel Meyer Suyapa Triminio-Meyer Joseph J. Molnar 《Aquacultural Engineering》2008,39(2-3):122-126
The levee pond is by far the most popular pond type for fish production. The specific object of this study was to develop a tool enabling extension, nongovernmental organization (NGO) agents, contractors and engineers in developing countries for computing levee pond excavation costs. We developed a spreadsheet-based computational tool in English and Spanish on the Microsoft Excel® platform. Knowing the original land slope and desired pond volume, one may compute excavation amounts that provide an acceptable cut-fill estimates based on a comparison with AutoCAD Civil 3-d®. The model computes projected costs in user-selected currency. Guidelines are provided for establishing pond bottom elevations and achieving the desired water depth. The model is relevant for small to medium sized levee ponds customarily used in aquacultural production in developing countries. 相似文献
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The pH change in 40 ml of buffer caused by 20 g dry soil may be multiplied by 5600 to provide the lime requirement of mud in a fish pond. The buffer contains 10 g p-nitrophenol, 7.5 g boric acid, 37 g potassium chloride, and 5.25 g potassium hydroxide dissolved and diluted to 1000 ml with distilled water; the buffer pH is adjusted to 8.00. 相似文献
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海上安全生产工作事关重大，安全生产必须警钟长呜，常抓不懈，本文结合本职工作实际，在认真总结加强海上安全工作经验的基础上，分析现状，针对存在的问题，提出如何建立海洋安全生产长效机制的意见，供上级领导参考。 相似文献
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This paper addresses a little‐discussed relationship between wild capture and mariculture, when the latter involves grow‐out of small wild‐caught fish or invertebrates in captivity. Seafood generated in this way is typically considered to be a form of aquaculture because it is assumed that, for animals removed from the wild when natural mortality is still very high, the protection conferred by culture operations will improve survivorship and enhance production. This assumption does not necessarily, however, apply when animals are removed well past the time of early high mortality. As one example of the implications of an early life‐history phase (ELP) fishery supplying culture operations, a preliminary study was conducted on an ELP fishery supplying live reef fish, especially groupers, in Southeast Asia. Grouper culture depends on both hatchery‐produced and wild‐caught fish which are then grown out to market size. Following interest to develop grow‐out operations in Indonesia, a pilot study was conducted to determine the sizes and capture rates of species of interest to the live fish trade, and to determine the likely environmental footprint of an artificial shelter (gango) type of capture method. From the results of the 15‐month study, we drew inferences regarding the sustainability of this fishing method and requirements of space, fish and materials for a viable grow‐out operation. The results showed that gangos were unselective for either species or size. Only 1.4% of the total fish catch (by number) were target species, mainly the grouper Epinephelus coioides, and most were large (mean total length was 13.6 cm) enough to have bypassed the early high mortality phase. Moreover, there were large non‐target catches that included many food fish species too small to be useful in catches. Given the large number and area of gangos needed for a viable operation, and that many groupers captured could probably have survived to reproduce, the ecological footprint of this approach could be substantial. These results, and literature on other ELP fisheries, suggest that these may often need management, have important links to other capture fishery sectors, and require careful evaluation of potential costs and benefits before introduction or development. 相似文献
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本文以2种大型浮游动物和1种绿藻、2种铜绿微囊藻为研究对象,初步研究了浮游动物对藻类的摄食关系。实验结果表明当栅藻和无毒铜绿微囊藻CHAB109密度均为1.02×106cells/ml时,拟老年低额溞对二者的去除率分别为54.20%和6.45%,大型溞的则为49.77%和64.77%。同时,拟老年低额溞对栅藻和CHAB109混合藻液中的两种藻均有较好的去除效果,分别为60.65%和34.43%,高于对纯种藻的去除率。在遮光条件下浮游动物摄食量更大,对藻的去除效果更优。拟老年低额溞在锡箔遮光情况下,对初始藻细胞密度为3.023×105cells/ml的有毒微囊藻PCC7806去除率达到32.37%。7d日龄的浮游动物个体大,摄食量也大,有较好的去除效果,且随着添加浮游动物数量的增加,去除率也随着提高。高浓度的藻细胞对两种浮游动物存活率影响较低浓度大。浮游动物应用于藻类水华的控制,作用不容忽视,且若条件适宜,浮游动物也可较好的控制有毒蓝藻。当选用浮游动物控藻藻类水华时,需综合考量选用物种种类、大小、添加数量等因素。 相似文献