长江上游干流春季禁渔前后三年渔获物结构和生物多样性分析

根据2000~2005年长江上游干流宜宾、巴南和万州3个江段三层流刺网的监测资料,分析了春禁前后3年渔获物结构和鱼类生物多样性的变化,对长江上游春禁效果进行了初步评价。春禁前后3年共监测到鱼类51种,隶属于3目18科（亚科）36属,以鲤科鱼类为主,占608%。春禁后,渔获物主要种类优势度有所下降,部分江段单位捕捞努力量渔获量表现出一定上升趋势,3个江段Margalef指数、Pielou指数和Wilhm改进指数有一定升高,表明种类丰富度有所提高,群落结构趋于复杂,春季禁渔有一定效果。春禁前后渔获物种类的波动,可能与这些种类种群数量少,难以采到有关;春禁后主要种类平均体长、体重仍表现出下降趋势,可能与过度捕捞及资源在短期内难以恢复有关。建议延长禁渔期、严格控制禁渔结束后的捕捞强度等措施来提高禁渔效果,并采取恢复江湖联系、保护重要渔业水域水质、实施水利工程生态调度等措施来配合春禁制度的实施。长江渔业资源的恢复和保护是一个长期而复杂的过程,对长江禁渔效果的准确评估还需要长期监测和深入研究。     

Rights and Conflicts in the Management of Fisheries in the Lower Songkhram River Basin,Northeast Thailand

A complex, pre-existing local property rights system, characterized by overlap and conflict, comprises the local basis for managing inland fisheries in communities of the Lower Songkhram River Basin (LSRB) of Northeastern Thailand. The components, conflicts and changes of the system are analyzed for fourteen communities, focusing on the auction system for barrages, an illegal and destructive, yet tolerated, fishery. These rights, adapted to gear type, seasonality, and habitat of the LSRB fisheries, are a critical social resource and proven management system that should be legitimized. Recommendations are made for both improving general inland fisheries policy and reforming the barrage fishery.     

渔港灰色聚类评估

渔港评估由于信息不完全，关系不明确，可视为一灰色系统。采用灰色聚类方法建立高、中、低3个白化权函数及聚类权系数，判断各个渔港所属灰类。渔港灰色聚类评估法是一种新的渔港等级评定方法，该方法所得渔港评估结果与实际情况基本一致，可供渔港管理部门进行渔港等级评估时参考。     

桑美台风风暴潮及其对张网作业影响的探讨

以2000年"桑美"台风风暴潮及此阶段张网作业的有关资料为依据,对风暴潮增水的形成机制、浙沪沿海风暴潮各阶段特征以及对张网作业的影响进行了探讨;对风暴潮增水在张网作业的积极作用与负面影响以及2000年八月半水张网作业丰收原因进行讨论.分析表明,在杭州湾滩浒岛附近海域,因风暴潮增水导致张网作业CPUE平均增幅为9.3%,最大增幅达23.5%.本文是一则风暴潮有利方面的报道,中国迄今尚属首次.     

Pikeperch (Sander lucioperca (L.)) in Decline: High Mortality of Three Populations in the Northern Baltic Sea

The development of three pikeperch (Sander lucioperca (L.)) populations in the northern Baltic Sea was monitored using standardized multimesh gillnets in 1995–2009. Declining trends in the abundances of pikeperch over 40 cm total length, low numbers of individuals older than 6 years, and high mortality rates were observed in all three populations. In the site with the largest commercial catches per unit area and a rapidly increased colony of great cormorants (Phalacrocorax carbo sinensis Blumenbach 1798), also the abundance of pikeperch below 40 cm total length and year-class strength showed declining trends. The adverse population level changes did not correlate with changes in water quality or eutrophication status. Together, the results suggest that in all study sites fisheries are harvesting a large proportion of the pikeperch soon after or even before reaching the maturity, and that predation from great cormorants may increase mortality of juveniles. Pikeperch is important not only for fisheries but also for ecosystem functioning, and our results point at the need for further management measures to ensure viable populations in the areas studied.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-013-0429-z) contains supplementary material, which is available to authorized users.     

Comanagement Practices Enhance Fisheries in Marine Protected Areas

Abstract:  Fishing activities worldwide have dramatically affected marine fish stocks and ecosystems. Marine protected areas (MPAs) with no-take zones may enhance fisheries, but empirical evidence of this is scant. We conducted a 4-year survey of fish catches around and within an MPA that was previously fully closed to fishing and then partially reopened under regulated comanaged fishing. In collaboration with the fishers and the MPA authority, we set the fishing effort and selected the gear to limit fishing impact on key fish predators, juvenile fish stage, and benthic communities and habitats. Within an adaptive comanagement framework, fishers agreed to reduce fishing effort if symptoms of overfishing were detected. We analyzed the temporal trends of catch per unit of effort (CPUE) of the whole species assemblages and CPUE of the four most valuable and frequent species observed inside the opened buffer zone and outside the MPA investigated. After the comanaged opening, CPUE first declined and then stabilized at levels more than twice that of catches obtained outside the MPA. Our results suggest that working closely with fishers can result in greater fisheries catches. Partial protection of coastal areas together with adaptive comanagement involving fishers, scientists, and managers can effectively achieve conservation and fishery management goals and benefit fishing communities and alleviate overfishing.     

渔业配额制度的起源、特点及展望

渔业配额制度是在渔业资源过度捕捞所导致的渔业危机和传统的投入控制管理失效的历史背景下,基于渔业资源生态特性而构建的一种产出控制的渔业管理模式。它是在总可捕量基础上发展起来的,并在冰岛、 新西兰等国家得以成功实施。该制度具有专属性、 可转让性、 激励性等外在法律特征。学者对于配额制度的法律特性持不同观点,认同其准物权的特性是主流观点。资源的生物特性以及制度的实质内涵告诉我们,无论是国际配额还是国内配额,制度要想取得实效,必须牢牢遵循不得超越总可捕量的共同义务这一要旨,通过落实有限准入、 加强监管等多种手段来保障这种共同义务的履行,才能实现资源的永续利用。     

Knowledge and Use of Biodiversity in Brazilian Hot Spots

Hot spots in Brazil include a variety of ecosystems, such as mangroves, forests, and the Brazilian savannah, locally called cerrado. Some of the rural populations in these hot spots are the caiçaras in SE Atlantic Forest coast, and the caboclos in the Amazon. In this study, we are concerned especially with the knowledge of caiçaras and caboclos, associated with practices that might have implications for management. Data were gathered through interviews with adults at the various communities studied, and through systematic observations, including samples of fishing trips and the mapping of fishing spots used in the Atlantic Forest coast. The use of resources from the surrounding vegetation includes collection of plants, cultivated fruit gardens, the swidden system, and a careful and managed extraction of fibres. Among animal resources, food taboos seem to be useful practices that might contribute to the maintenance of local natural resources. Potential management practices should be locally developed, such as the informal division of fishing spots in Atlantic Forest sites, and the maintenance of the diversity of cassava varieties in both the Atlantic Forest and Amazonian areas.     

Exploring corruption in fisheries

This paper explores corruption in global fisheries. While reducing corruption is critical for the effective management of the fisheries sector and the fulfilment of the UN's sustainable development goals (SDGs, and SDGs14 and 16 in particular), to do so, it is necessary to first have a systematic and comprehensive understanding of what corruption is and how it is manifested in the sector. There is literature on illegal, unregulated and unreported (IUU) fishing, but not much on corruption. The paper proposes an analytical framework and applies it with six revelatory cases to improve the conceptual clarity of corruption in fisheries. Specific corruption problems found in licensing, negotiating access agreements, lax enforcement, extortion, political corruption, money laundering and tax manipulation, human trafficking, etc. can therefore be better identified through this analysis, which lays a base for systematic responses to tackling corruption in fisheries and accordingly furthering the sustainable development of the sector.     

The Prestige oil spill and its economic impact on the Galician fishing sector

The sinking of the Prestige oil tanker on 18 November 2002 off the coast of Galicia, Spain, had important economic, environmental and social ramifications. The aim of this paper is to carry out an initial analysis of the costs related to a halt in fishing activities in Galicia between November 2002 and December 2003. This involves three different steps: an assessment of the cost of the preventative and palliative measures introduced by Spanish public administrations (compensation for affected fishermen and shellfish fisherman); an indirect evaluation of the implications of the disaster (via a study of data on production); and a direct appraisal of the economic impact of the event (reduction in income), using questionnaires completed by a representative sample of fishermen and shellfish fisherman. The results obtained from these three methods of estimating losses are compatible. By December 2003, losses to the Galician fishing sector stood at an estimated EUR 76 million.