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61.
兴城现代渔业园区可持续发展的几点建议   总被引:1,自引:0,他引:1  
孔维军 《水产科学》2006,25(11):593-594
几年来,在省、市海洋与渔业主管部门亲切关怀和正确领导下,兴城现代渔业园区的养殖面积由2002年的0.8×10 4 m 2发展到2005年的3.0×10 5m 2,园区的养殖场家达到80户,年产大菱鲆商品鱼2000 t以上,年产值达1.2亿元,实现利润0.5亿元,已成为辽宁省的大菱鲆养殖基地.但是,随着近两年养殖规模快速发展,井盐水供不应求、鱼苗供求矛盾等问题也逐渐显露出来,这势必将影响和阻碍园区的可持续发展.  相似文献   
62.
在分析了NOVELL网和MELSEC网的基础,提出一种MELSEC-NOVELL网关的硬件设计实现方法。  相似文献   
63.
Abstract  Socioeconomic characterisation of fishing activities in the Veracruz Reef System National Park was used to develop a management system which balances the community's livelihood, and the conservation needs of the protected area. A survey was applied to four sectors of the fishing community: the fishers, fishers' wives, retailers and local population. The survey determined their perceptions about: (1) fishing as a lifestyle; (2) economic alternatives; (3) perspectives about the future; (4) environment; and (5) knowledge of the National Park as a protected area. Fishers devoted an average of 27 years fishing, investing an average of 12 h per day giving a regular income of 15–20 US$. Most interviewed (60%) were full-time fishers, with fishing the only family income source. Fishers are predominately educated to primary school level (64%).The main problem faced by fishers and the communities were economic opportunities but 89% believed that mariculture could be an alternative income source. There was strong ecological awareness, with 75% aware of the decline in fisheries resource and 62% knowing about the role of protected areas. There was divided opinion about future perspectives. Inefficient organisation and communication between authorities and fishers were identified as obstacles to co-management. Discussion on alternative incomes and a proposal involve fishers in co-management initiatives are presented.  相似文献   
64.
日本是世界上最大的水产品消费国和进口国,其水产品流通体系具有很强的代表性、借鉴性,文章通过分析日本水产品流通渠道的形式和特征,结合中国现阶段水产品流通结构的比较,提出中国构建有效水产品流通渠道的建议。  相似文献   
65.
  • 1. In order to promote the establishment of the first marine protected area (MPA) in Taiwan, the conservation values of 12 reef sites in the Penghu Islands were evaluated. The results together with a 6‐year surveillance programme revealed that the Chinwan Inner Bay (CIB) possesses the best coral community in the Penghu Islands with the highest coral cover, high species diversity and habitat types, as well as a high conservation value.
  • 2. Utilization of biological resources and socio‐economic factors of CIB were investigated by intensive field surveys and a complete visit‐and‐poll survey respectively. Most of the fishing at CIB is for recreational purposes and is characterized by low investment, low harvest rates, high dependence on weather conditions, and self‐consumption.
  • 3. The socio‐economic data showed that there was basically no direct conflict of interests with local communities at two neighbouring villages, and most local residents indicated that they would support the MPA proposal.
  • 4. A blueprint for a CIB MPA based on the results of these biological and socio‐economic investigations is proposed. Environmental threats including anchor damage and the predation of Drupella snails need to be ameliorated and monitored through the implementation of appropriate management. The involvement of local communities is key to the success of this MPA and environmental education is recommended to promote public awareness.
Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
66.
渔业公共资源管理既是一个国际性难题,也是我国渔业现代化和市场经济进程中,必须面对和妥善解决的渔业公共资源问题.本文重点分析了当前我国渔业公共资源存在的冲突矛盾,揭示其内在共性特征,总结了福建省渔业公共资源管理的经验和管理模式,结合渔业公共资源管理现状,提出了进一步完善我国渔业公共资源管理的制度设计思路和体制机制设计的原则,研究了适应我国社会主义市场经济条件下的渔业公共资源管理思路.  相似文献   
67.
首先分析了集中供热热网系统能源浪费的表现和程度,进而提出了改造和完善的节能措施。  相似文献   
68.
渔业劳动力作为农业劳动力的重要组成部分,其转移的研究必然要以农业劳动力转移的研究为基础。文章回顾了我国渔业、农业剩余劳动力转移的研究,包括农业剩余劳动力的数量、劳动力转移的影响因素、解决劳动力转移的对策以及转移所带来的影响等。在此基础上归纳出两种类型的劳动力转移的特点;指出了现有研究存在的问题和今后进一步研究的方向。  相似文献   
69.
International comparison of virulence profiles of Pyrenophora teres f . teres (Ptt), the cause of barley net blotch, is seriously restricted by inconsistencies in differential testers used among researchers. This paper reports an attempt to develop an appropriate set of differentials to standardize characterization of Ptt populations globally. Fourteen barley genotypes (Canadian Lake Shore (CLS), Harbin, c-8755, c-20019, Manchurian, Tifang, CI 9825, CI 5791, CI 9819, Beecher, CI 9214, Skiff, Prior and Corvette) were selected from among genotypes previously used as Ptt differentials. Three cultivars (Pirkka, Haruna Nijo and Harrington) were included to identify a universally susceptible control. Genotypes were inoculated with approximately 1000 Ptt isolates from Russia, Europe, Australia and Canada. The mean reaction frequency of genotypes ranged from highly resistant (CI 9819, CI 5791, c-8755 and CI 9825) to highly susceptible (Harrington, Haruna Nijo and Pirkka). The best differential abilities were demonstrated by Harbin, CLS, c-20019, Manchurian and Prior. Application of cluster analyses identified genotypes with similar reaction patterns, which supported a reduction of genotypes in the set. When combined with an algorithm comparing the ability of individual genotypes to discriminate among Ptt isolates, a further reduction of genotypes was justified. A new, concise set of barley genotypes for differentiating virulences in Ptt was formulated. It is proposed that these genotypes be adopted as the standard, international differential set to characterize and identify the virulence properties of Ptt populations across environments. The new Ptt differential set consists of the genotypes c-8755, c-20019, CI 5791, CI 9825, CLS, Harbin, Prior, Skiff and Harrington.  相似文献   
70.
紫荆光合日进程及光响应   总被引:6,自引:1,他引:6  
自然条件下使用LCA-4型便携式光合测定系统研究了紫荆连体叶片的光合日变化及光响应。结果表明:(1)净光合速率的日进程曲线呈“双峰”型,胞间CO2浓度的日进程基本与净光合速率相反,中午胞间CO2浓度增高,表明净光合速率午间降低主要受非气孔限制因素的影响。暗呼吸速率日进程为单峰曲线,中午最高。气孔阻力的日变化曲线是单谷型,午间最低。(2)一天分时段光响应试验表明,饱和光强和表观量子效率上午最高,中午最低,下午有所上升。下午的光补偿点是上午的2倍,中午则是上午的近3倍。不同时段遮光都使得气孔阻力和胞间CO2浓度升高。  相似文献   
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