Fishing‐induced evolution of growth: concepts,mechanisms and the empirical evidence

The interest in fishing‐induced life‐history evolution has been growing in the last decade, in part because of the increasing number of studies suggesting evolutionary changes in life‐history traits, and the potential ecological and economic consequences these changes may have. Among the traits that could evolve in response to fishing, growth has lately received attention. However, critical reading of the literature on growth evolution in fish reveals conceptual confusion about the nature of ‘growth’ itself as an evolving trait, and about the different ways fishing can affect growth and size‐at‐age of fish, both on ecological and on evolutionary time‐scales. It is important to separate the advantages of being big and the costs of growing to a large size, particularly when studying life‐history evolution. In this review, we explore the selection pressures on growth and the resultant evolution of growth from a mechanistic viewpoint. We define important concepts and outline the processes that must be accounted for before observed phenotypic changes can be ascribed to growth evolution. When listing traits that could be traded‐off with growth rate, we group the mechanisms into those affecting resource acquisition and those governing resource allocation. We summarize potential effects of fishing on traits related to growth and discuss methods for detecting evolution of growth. We also challenge the prevailing expectation that fishing‐induced evolution should always lead to slower growth.     

Circuits of scrap: closed loop industrial ecosystems and the geography of US international recyclable material flows 1995–2005

The recycling of scrap material has been identified as an important strategy in the larger theory of industrial ecology. Industrial ecology argues that the traditional model of industrial activity needs to be transformed into a 'closed loop' industrial ecosystem where used materials (scrap) and by-products would substitute for virgin materials during production processes. The recycling of scrap material forms part of this larger effort to reduce the overall environmental impact of production and consumption. A key, but as yet, unresolved question in this process is the geographic scale (local, regional, national, global) at which loop closing should take place. This preliminary empirical research examines the export and import geography of the seven largest (by weight) US scrap commodities (iron and steel, paper, plastics, aluminium, copper, nickel and zinc) between 1995 and 2005 to ascertain the extent to which US scrap flows overseas and how that might affect our understanding of how material loops can close. Other than an integrated export and import relationship with Canada, the results suggest that there are two distinct circuits of scrap flows in the USA. The USA exports a substantial portion of the recyclable scrap generated each year to rapidly developing countries, while importing smaller quantities of scrap from the EU. With the major exception of exporting higher value iron and steel scrap to China, the US tends to export lower value scrap and import higher value scrap. In part this reflects imbalances in the supply and demand for scrap between the USA and the developing world, the lack of potentially available scrap and the absence of a robust recycling infrastructure in the developing world. Although such scrap circuits are probably not ideal, the use of US scrap in the developing world is both a realistic and preferable alternative in the short to medium term than virgin production.     

湘澳经贸合作的新机遇与新机制

湘澳合作是在CEPA及泛珠三角"9+2"框架下的区域合作,其在招商引资、会展、旅游、消费维权等合作方面取得了一些进展,但合作的广度和深度还不够,湖南没有充分利用好澳门的"平台"作用,自身的特色和优势没有得到充分体现.长株潭城市群被批准为两型社会试验区为湘澳合作提供了新的机遇,全球性的金融危机也为湘澳合作带来了新的挑战.通过对湘澳区域关系和合作机制的反思,认为湘澳合作应由政府推动的合作机制转变为市场引导和政府推动结合的新机制,并充分发挥民间组织的作用,以推动湘澳合作取得更大的进展.     

The end of shark finning? Impacts of declining catches and fin demand on coastal community livelihoods

For several decades, fishing sharks for their fins has provided important livelihoods for eastern Indonesian coastal communities that fish the Halmahera, Arafura and Timor Seas. Fishery and interview data collected in 2012-13 from three case studies on the islands of Seram, Aru and Rote were used to examine changes in shark fishers’ livelihoods over the preceding 20 years. While recent declines in catches and shark fin prices have had a substantial impact on fishers’ livelihoods, the fishery's low visibility in some areas of its geographic range and its political complexity in general have meant that government and international development agencies have largely been unaware of this impact. Many respondents remembered the Asian Financial Crisis in 1997-98 and the turn of the millennium as a time when sharks were still abundant and shark fin prices high, but were concerned about the on-going fall of shark fin prices since March 2012. High-value species, particularly guitarfish, hammerhead and sandbar sharks were most affected, losing up to 40% of their pre-2012 value. These changes, combined with the loss of fishing grounds, few attractive options for alternative income and restrictive debt relationships with shark fin bosses, have led some fishers to resort to high-risk activities such as blast fishing, illegal transboundary fishing, and people smuggling. This paper examines the multi-layered causes and consequences of fishers’ decision-making in response to adverse changes in their fishery, and explores options and obstacles to pursuing livelihoods that carry lower environmental, financial and personal risks.     

Global energy scenarios and their implications for future shipped trade

About half of the world's oil supply, a fifth of coal supply and a tenth of natural gas supply are traded by ship. Accordingly, any significant shift in the size and shape of the global energy system has important consequences for shipping, which underpins international trade and supports economic development. The Paris Agreement requires an acceleration of the drive towards energy system decarbonisation. Yet, the International Maritime Organisation's understanding of the future is more in line with the high-carbon scenarios analysed here. This paper is a first comprehensive and global assessment of implications of fundamental changes to global and regional energy systems for international shipping, under-researched in energy scenarios consistent with deep decarbonisation. It concludes that, despite uncertainties (particularly with negative emission technologies), fossil fuel trade by the middle of the century will almost certainly be significantly lower under low-carbon than under high-carbon scenarios, and (for oil and coal) lower than in 2012. As to bioenergy and captured carbon dioxide, while their supply is expected to increase during a low-carbon transition, worldwide shipped trade in these commodities will not necessarily grow, based on the analysis in this paper. In other words, if the low-carbon futures envisioned in the Paris Agreement materialise, energy-related shipping will likely decline (by a quarter for oil and by 50% for coal in the median < 2 °C scenarios by 2050), with significant ramifications for policies and regulation in the shipping sector and international trade.     

中国商品贸易结构不均衡性对地缘经济格局的影响

从国家对外经济联系中不同产业和产品结构的进出口贸易视角,考察中国^①（① 由于数据限制,本文研究区域为中国大陆地区,不包括港澳台地区。）地缘经济格局特征与影响。研究表明,中国商品贸易的总体态势是资源产品进口对富含能源国家的高依赖及工业制成品净出口对国际市场的强需求的不均衡特征;空间上则表现出国别、地区和方式较为单一且相对稳定,这可能会导致中国地缘经济与其他国家关联强度有一定的倾向性。集成资源产品进口和工业制成品进出口多指标显示,以工业制成品进出口为主的外向经济是影响中国当前地缘经济格局最主要的因素,而资源产品进口则次于工业制成品的作用,且石油和铁矿的作用高于天然气;在空间上形成了以重点经济发达国家与其外围周边国家为重点面域,联合重点能源国家为扩展的“面-点”地缘经济格局,中国进出口贸易地区大致形成了由近及远的多圈层结构,且关联度较低的国家镶嵌其中而表现出破碎化的特征。这一格局昭示未来一段时间中国地缘局势总体稳定,但受诸多不可控因素的影响,积极开辟和寻求多元化的地缘经济空间是有效应对对外经济联系突发事件的重要途径。     

中国八个地区的消费需求分析

本文应用经济学的消费需求分析模式,分析了我国８个代表地区的消费需求特性,并讨论了其对可持续发展的意义。     

当代世界技术贸易的地理格局初探

本文在论述当代国际技术贸易地理分布的基础上分析了当代国际技术贸易的流动特点,并探讨其成因,最后指出了当代国际技术贸易地理的主要研究领域。     

山东省对外贸易结构优化与FDI流入的互动机理——基于机电产业的经验分析

通过对山东省贸易结构与FDI流入间的关系进行的定性分析和以山东省1993-2004年为样本空间进行的实证检验模型表明,山东省外资流入与对外贸易结构优化间存在长期均衡的互动影响并存在相互作用机理.FDI流入会通过提升产业结构优化进程、改善产业分工地位和加快要素积累速度等促进贸易结构优化,贸易结构优化会引致外资产生利润空间追求效应、边际产业扩张效应和空间偏好效应而带来FDI增长,两者间的作用机理对山东省外资引导政策的制定具有一定的启示意义.     

基于山东半岛港口资源的农产品外贸物流空间及其优化

山东作为我国农业大省和强省,既有丰富的农业物源,又有突出的区位优势,基于港口资源的农产品物流统筹规划,将农产品外贸物流纳入山东区域物流的框架体系之中,提高农产品的附加值,加大农产品物流的增值服务功能,提升山东省农产品的国际竞争力.构建农产品产地物流、中转物流及港口物流供应链的集成化系统,以适应农业产业体系建立的国际化合作与竞争之要求,探索农产品外贸物流的空间布局及优化问题就成为我们目前亟待解决的关键课题之一.