生物多样性和可持续渔业管理经济

海洋生态系统是非常复杂的,而且海洋生物种类之间也是相互依存的。相应的如果一个物种消失就会对其它物种产生一种级联效应。鱼类科学家倡导一种基于生态系统的手段来进行渔业管理,以满足长期可持续发展的目标。本论文对种类之间相互依存的复杂关系和生物总量与生物表现型多样化之间的关系进行模拟建模。结果表明,如果不考虑生物多样性,平衡的储备量和捕捞或生产量水平就会被高估。相应的如果鱼类种类是不同的,建立在单一渔业资源管理上的渔业政策往往会过高的估计捕获潜能,结果导致过度捕捞和鱼类资源储量的崩溃。     

Optimal vessel size and output in the Australian northern prawn fishery: a restricted profit function approach*

Individual transferable quotas (ITQs) are to be introduced into Australia’s Northern Prawn fishery in the near future. Total allowable catches (TACs) are to be set with the objective of maximising economic efficiency in the fishery. Under ITQs, vessel owners have the ability to adjust their fishing activities to maximise profits and changes in fleet structure resulting from management changes need to be considered when determining TACs. A restricted profit function for the fishery was estimated to determine the optimal vessel characteristics and output levels as a guide to how the fleet may adjust under an ITQ system. Vessels were found to be currently close to their optimal size given average historic prices and current stock conditions. However, higher tiger prawn stocks are expected to result in the average size of vessels increasing, with rising fuel prices also likely to result in capital being substituted for fishing days. Optimal average vessel‐level catches of the main species are lower than current average vessel catches for a wide range of input and output prices. These changes in vessel characteristics and behaviour need to be incorporated in the derivation of the optimal TACs if economic efficiency objectives are to be achieved.     

Downside risk in reservoir management

Downside risk, which refers to deviations below a threshold, is often important in water management decisions, especially in areas with large and skewed variations in precipitation patterns. In this paper, we present a model for a reservoir manager who is downside risk averse and who performs a dynamic allocation of irrigation water, taking into account the negative effects of droughts on farm profits and different environmental constraints. We analyse the water stock, flows and agricultural profits for alternative environmental restrictions and thresholds for irrigation levels and find that stricter environmental constraints increase total water supply and carryover stock, while higher penalty thresholds lead to their overall decrease. Furthermore, increasing penalty thresholds leads to a higher emphasis on avoiding shortages, at the expense of lower average profits.     

“东海无鱼”应对措施探讨

近年来，东海近海渔业捕捞单位能耗渔获量减少，渔获物中经济鱼类的比重下降，整体营养级水平走低，并且渔获物低龄化、小型化趋势明显，这都说明渔业资源退化已经到了极其严重的地步，严重影响了渔民生计、渔区发展和社会稳定。这一问题的出现表面上看是捕捞过剩和环境污染造成的，但其深层次原因在于我国渔业管理制度不科学，需要进行反思，加强顶层设计，深入研究渔业管理制度和科学保护问题，按照堵疏结合的原则，加强管理和执法的同时，加大资源修复力度。     

从樟州渔村看我国渔业发展的几个问题

为深入基层了解渔区渔业情况,践行我部“接地气、察民情”实践活动要求,我们来到重点渔区浙江省舟山市樟州村,实地调研渔业发展和渔业管理工作。调研了解到,我国海洋渔业的可持续发展面临挑战,渔业安全生产尚存薄弱环节,渔业政策和管理措施的执行力需要加强。渔业的可持续发展,要下大力气调结构、转方式,建设现代渔业,同时要控制捕捞强度、养护渔业资源。要努力构建渔业安全生产长效机制,保障渔业生产安全。渔业政策和管理措施的有效执行,在于政策设计科学,可操作性强,宣传到位并得到理解支持,要重视执法能力的建设。     

广西现代渔业发展探析

广西是我国渔业主产省份之一,近年来广西渔业发展迅速,成效显著,但与现代渔业的要求相比,广西受整体经济发展水平偏低等因素的影响,在设施条件、产业布局与结构、市场体系、科技能力及远洋渔业等方面与其他渔业大省相比还存在一定差距。本文通过实地调研和渔业统计数据的对比分析,研究了广西渔业发展潜力和制约因素,提出广西要在充分认识当前渔业发展形势和分析自身优劣势的基础上,明确现代渔业发展的基本思路,"壮大优势、明确重点、培育新的增长点"应是广西现代渔业重点关注的几个方面。     

Optimal management of the New Zealand longfin eel (Anguilla dieffenbachii)*

Annual recruitment of the New Zealand longfin eel (Anguilla dieffenbachii) has decreased by 75 per cent since significant levels of commercial fishing began in the early 1970s. This motivates application of a multiple‐cohort bioeconomic model to a New Zealand longfin eel fishery to investigate its optimal management and ascertain the suitability of existing regulatory policy. The use of historical harvest to calculate total allowable catch is asserted to be unsustainable based on recovery dynamics. In addition, individual transferable quota systems are argued to be fundamentally flawed for the protection of longfin fisheries because of high‐grading, low‐surplus production and a current lack of effective stock‐assessment procedures. Area closure and the spatial definition of harvest rights are attractive alternatives given the territoriality of longfins and high larval spillover. The importance of unfished reserves is reinforced when significant uncertainties regarding population strength, harvest intensity and growth dynamics are considered. Restriction of exploitation to older cohorts in fished areas is demonstrated to maximise economic yield.     

我国渔港研究现状综述

渔港是渔民生产生活的重要场所,是渔船避风停泊的重要基地,在渔业生产管理、"平安渔业"建设、渔业水域环境保护以及渔区经济社会发展中发挥着重要作用。一直以来,学者们关于渔港建设等方面的探讨研究从未间断过,这些研究成果对于推进各地渔港建设和管理步伐,充分发挥渔港对渔区经济社会发展的辐射带动作用,促进渔业可持续健康发展有着不可忽视的作用。本文按时间分段对中国渔港研究现状进行了一次学术性梳理,指出我国渔港在20世纪70～80年代起步阶段、90年代发展阶段和21世纪以来的繁荣阶段的不同特点,以期对今后的渔港研究以及渔港建设起到一定的借鉴和促进意义。     

海洋捕捞作业影响因素判别及其作用机理

市场经济条件下,海洋捕捞主体生产行为的最优选择是其自身海洋捕捞作业技术水平、海洋捕捞物资性价比、海洋自然渔业资源存量、作业海域生态环境质量、作业海域自然气候条件、渔获物商品化程度和水产市场价格体系综合作用的结果。在其它因素相对不变的条件下,仅有反映水产市场价格体系变化的捕捞物资价格与渔获物价格的比值与海洋捕捞作业规模呈反向关系,其余六个变量均与海洋捕捞作业规模呈正向关系。     

战后日本渔业转型期的渔船管理

渔政的核心内容是渔场管理和渔船管理,特殊时期的渔政管理方法和策略具有重要的借鉴意义。二战后的日本的渔业一片破败,在美国占领军司令部的严厉控制以及国内经济全面崩溃的情况下,日本渔业能够迅速从复兴到发展,并能走出自成一体的渔业管理及渔船管理模式,引起普遍关注。本文从国际环境、国内民生、渔业资源状况等多角度,对战后特殊时期的日本渔业在渔场、渔船、渔政等方面进行考察,分析它在演变历程中的背景因素,探讨其渔船管理的特点,为我国相关渔政提供参考。     

国内海洋渔村建设研究文献综述与展望

渔村建设是推进农业现代化发展的主要任务之一,也是加快农渔村旅游发展的"助推器"。本文把海洋渔村作为研究重点,从近10年来国内海洋渔村建设研究主流方向入手,辅以国外成功案例对海洋渔村建设、模式和渔业经济产业结构进行了归纳综述,并对海洋渔村建设中存在的不足进行了评述,提出了海洋渔业和渔村建设的相关建议:(1)优先保护海岸和近海资源与生态环境;(2)创新农渔产业转型与升级;(3)规划先行与科学管理。结合目前研究新方向提出了美丽渔村建设体系框架,即从美丽渔村社区建设、产业结构、休闲渔业和基本原理研究视角出发,将渔村社区建设和产业结构有机整合,旨要在环境生态保护的前提下促进二者的绿色经济发展,并对未来海洋渔村建设研究进行了展望:(1)渔村建设概念亟需统一,研究体系亟需明确;(2)渔村建设与相关产业融合(协同发展)问题仍将是研究热点;(3)渔村建设需不断加强国际比较研究。     

我国北太平洋长鳍金枪鱼发展研究

本文分析了北太平洋长鳍金枪鱼的渔业现状和国际组织对该渔业资源的管理措施。目前,长鳍金枪鱼已经处于充分开发状态,2004年总渔获量已达到86073t,主要捕捞国家是日本、美国、中国台湾、加拿大等,主要捕捞渔具是延绳钓、曳绳钓等。在此基础上,本文分析了中国的渔业现状,并从政府支持、捕捞技术、渔场开发和渔业统计等方面提出了我国在北太平洋发展长鳍金枪鱼渔业的对策。     

印度洋金枪鱼渔业概况及中国金枪鱼船队发展对策分析

印度洋是世界上第二大金枪鱼产区,同时日益成为中国重要的金枪鱼作业渔场。基于印度洋金枪鱼委员会提供的数据,本文分析了印度洋金枪鱼渔业的发展概况及主捕鱼种的利用情况。同时,本文简要分析了中国金枪鱼船队在印度洋的发展概况,并对中国金枪鱼船队的发展前景作了简要探讨。加强渔业管理、完善渔业管理措施、加大研究投入等将是中国政府发展印度洋金枪鱼渔业的重要任务。     

价值链视角下福建省渔业经济效率与影响因素对比

目的 文章以福建省为研究区域，选取渔业价值链中最具代表性的“生产—加工”两阶段，对比分析经济效率及影响因素。方法 从价值链视角构建渔业“生产—加工”两阶段投入产出系统，讨论选定指标，基于SBM-Tobit模型测度效率和影响因素。结果 （1）福建省渔业“生产—加工”两阶段效率均较低，生产阶段效率远高于加工阶段效率。（2）福建省渔业生产阶段效率呈现“大分散、小集聚”的分布特征，沿海和西北地区较高，闽西南地区较低；加工业主要分布在沿海地区，效率普遍较低。（3）工业化和城镇化对渔业生产阶段效率主要起负作用，消费水平、渔业经济规模、集约化和捕捞强度对生产和加工阶段效率均起正作用，沿海和内陆地区的影响机理存在一定差异。结论 福建省渔业“生产—加工”两阶段效率均具有较大的提升空间，需重点提升加工阶段效率，以拉动渔业价值链整体效率提升。     

Valuing recreational fishing in Tasmania and assessment of response bias in contingent valuation*

We report results from contingent valuation studies in each of two Tasmanian fisheries that estimate the value of a day’s recreational fishing. Published studies estimating the economic value of recreational fishing in Australia and New Zealand are limited, although the economic and social benefits associated with this activity are sizable and the importance of understanding the behaviour of recreational fishers for the sustainable management of aquatic resources is well recognised. In our contingent valuation surveys, we use a double‐bounded version of the dichotomous choice question, which improves the statistical efficiency of the estimates relative to those based on a single dichotomous choice question. We test and control for response bias, in the form of anchoring and a shift effect, that may occur in data collected using a double‐bounded dichotomous choice (DBDC) elicitation format. We highlight the importance of identifying and correcting for response bias in DBDC models on a case‐by‐case basis. Our estimation results show that there is no significant difference in the willingness to pay for a day of recreational fishing across individuals who caught different number of fish in either fishery. This suggests that high and low catch fishers placed the same value on a day’s fishing.     

舟山水产品产量结构及渔业人力资源结构分析

水产品产量结构与人力资源结构是渔业产业转型升级路径研究的基础内容,本文通过因子分析法对2000-2013年舟山市水产品产量结构和渔业人力资源结构进行了分析。结果显示:水产品产量结构的综合得分总体趋势呈上升,第一公因子是捕捞因子,第二公因子是养殖因子;渔业人力资源结构的综合得分总体趋势呈下降,公因子是其他因子。建议调整舟山水产品产量结构,发展远洋渔业及海水养殖产业;人力资源结构调整应向水产品精深加工和贸易方面展开。     

A study of the impact of direct trade on Taiwan's fishery sector with special reference to the effect of China's WTO accession

After Taiwan became a member of the WTO in 2002, its tariff rates for fishery products decreased by an average of 35.5% from the level in 2001. Direct imports of fishery products from China would be allowed in 2004. These tariff reductions and the relaxation of import restrictions will have a strong effect on Taiwan's fishery sector. In this paper, we present an analysis of how fishery production, prices, input usage, and welfare distribution might react to trade liberalization. In addition to evaluating the overall impact of tariff reduction on Taiwan's fishery sector, we assess the effects of China's WTO accession on the Taiwanese market. We use a fishery sector equilibrium model in which 40 products and 68 fishing activities are identified. The model also includes an import–export subsector, a factor input subsector, and a supply–demand equilibrium condition to analyze the distributions of social welfare due to trade liberalization. Three simulations are conducted to investigate the impact of tariff reductions in 2004, 2 years after Taiwan has jointed the WTO. The results indicate that Taiwan's fishery sector will be adversely affected when it encounters the extremely low import prices of certain fishery products from China. The total production of the fishery sector and its value are predicted to decrease by 4.03% and 9.96%, respectively, in 2004. Aquaculture would suffer the heaviest loss with a 7.48% reduction in the production and a 19.23% reduction in its value. The demand for labor will decrease by 8.71%. The effect is most pronounced in aquaculture in which the demand for labor will go down by 11.40% and the wage rate will decline by 14.28%. To meet the challenge of globalization, the Taiwanese fishery industry will have to diversify, and improve its operational efficiency as well as production and distribution structures for a sustainable development.     

No‐take marine reserves and illegal fishing under imperfect enforcement

No‐take marine reserves have been increasingly advocated as an effective means of supporting marine ecosystems and conserving fisheries resources. A major problem that can hinder the effectiveness of no‐take reserves is the incidence of illegal fishing, which has created significant ecological and economic losses in global fisheries. We construct a bioeconomic model to explore the connection between the effects of no‐take reserves and illegal fishing activities in relation to the level of regulatory control of illegal activities in the reserve and fished areas. Our parameterised model shows that the effects of no‐take reserves on both the extent of illegal fishing and the fish biomass critically depend on illegal fishing regulations and the scale and patterns of fish dispersal. In a fishery where illegal fishing can only be partially controlled, increasing the size of the no‐take reserve may result in a lose‐lose situation in which the level of illegal fishing effort increases and the total biomass decreases. Our results further show that when the pattern of fish dispersal is density dependent, imposing a stricter control on illegal fishing in either reserves or fished areas increases the aggregate level of illegal fishing.     

我国沿海渔民转产转业问题的成因分析

我国沿海渔民转产转业的直接成因是因三大双边渔业协定的签订实施而导致的传统渔场压缩,但其共同的原因则是技术进步、环境污染及过度捕捞所引起的渔业资源衰竭,而造成渔业资源过度利用的深层原因则是海洋渔业资源的共有财产特性及海洋渔业的自由准人机制,其核心是产权问题.     

依靠法制和科学规范渔具许可制度——以底扒网、帆张网为例

本文针对江、浙两省渔业管理条例有关禁用渔具条款,以底扒网和帆张网为例,从法律和技术两个层面进行剖析,阐明作者观点:①法律体系层面,两渔具不应在《渔业法》规定"禁用渔具"类别内,两省渔业管理条例分别定性其为禁用渔具,不符合"下位法不得与上位法相低触"之立法原则;技术的自然属性层面,两渔具体现了客观的自然属性与人的主观能动性的综合,不失具独特的先进性。②相关禁用渔具法律条款之法律绩效无法实现的症结在管理层面,因此工作着力点应放在强化管理上。③建议对两省渔业管理条例中的有关禁用渔具条款启动"法律修改"程序,并同步实施与解禁渔具相配套的制度与体系构建,即根据幼鱼资源发生和时空分布等客观规律,积极引导捕捞生产,努力寻求利用资源与保护幼鱼之间的平衡。④基于配套法规之科技支撑体系难以短期解决现状,与解禁渔具配套法律体系只能分步构建和逐步完善,可先依据《渔业法》第三十条赋予权限,依法针对资源敏感区、幼鱼高发期实施探索性的临时禁渔规定,并可同时出台最小网目尺寸、幼鱼比例抽检等辅助性渔政管理规定等。