各国水产品贸易的影响因素和中国的贸易潜力

运用扩展的三维引力模型考察了1990–2009年间122个国家的双边水产品贸易情况,对影响各国水产品贸易的主要因素进行了实证分析。在此基础上,对我国水产品出口和进口贸易潜力进行了测算,发现中国水产品贸易总体上表现为"贸易饱和",但对印度等市场存在"贸易不足"。最后就如何提升一国的潜在贸易量给出了具体建议。     

中亚五国自华进口贸易技术溢出及碳排放影响研究

梳理1992—2018年中亚五国碳排放变化过程,运用碳排放库兹涅茨曲线模拟人均碳排放与人均国内生产总值（GDP）的关系,基于中亚五国人均GDP、工业增加值、研发投入、自华进口中间品和资本品的技术溢出存量等指标,构建面板数据固定效应模型以探究碳排放影响机制。结果表明：（1） 中亚五国碳排放先降后升,各国碳排放的变化率波动较大,其中哈萨克斯坦碳排放占中亚五国碳排放比重最大。（2） 就人均碳排放与人均GDP拟合的碳排放库兹涅茨曲线关系而言,哈萨克斯坦和土库曼斯坦表现为倒N型,乌兹别克斯坦、塔吉克斯坦、吉尔吉斯斯坦和中亚五国表现为N型。（3） 中亚五国自华进口额呈现较快的增长趋势,其中自华进口的中间品和资本品合计约占自华进口总额的3.920%~10.976%,中亚五国整体及各国中间品技术溢出存量均明显大于资本品技术溢出存量。（4） 在影响中亚五国碳排放的诸多因素中,人均GDP和工业增加值占GDP比重的回归系数显著为正,人均GDP、工业增加值占GDP比重每上升1%,碳排放分别增加0.337%和0.343%,研发投入、交互项LnZJ_it×LnS_it（中间品技术溢出存量的自然对数×工业增加值占GDP比重的自然对数）的回归系数显著为负,研发投入每增加1%,碳排放可减少约0.432%,在降低因工业增加值占GDP比重上升导致的碳排放方面,中间品技术溢出存量的影响极小。     

Examining the Variability of Crossing Times for Canadian Trucks at the Three Major Canada–U.S. Border Crossings

Land borders connecting Canada and the United States are vital transportation facilities for the two countries. Truck crossing times at these facilities can have a significant impact on the performance of the economy. To date, knowledge about border crossing times has been limited due to lack of detailed data on the Canadian border. This article explores and models the patterns of crossing times at the three major land crossings connecting Canada to the United States: Ambassador Bridge, Blue Water Bridge, and Peace Bridge. The analysis is based on 387,775 border crossing truck trips that were generated between Canada and the United States over a course of twelve months. Seemingly unrelated regression (SUR) models are estimated to evaluate the seasonal and hourly crossing times of Canada- and U.S.-bound trips on each border crossing, controlling for traffic intensity in the models. The SUR modeling approach is chosen to control for potential cross-model correlations. The results suggest that crossing times at the border vary by season and hour of the day. Crossing times also vary by direction of traffic and by type of day (i.e., weekday vs. weekend). Traffic intensity has a significant influence on crossing times at two of the crossings but not the Blue Water Bridge. Finally, crossing times are more variable during the summer season and tend to be higher during the late evening hours and past midnight.     

CONTESTING PISCO: CHILE,PERU, AND THE POLITICS OF TRADE*

This article examines the geography of pisco, a South American brandy claimed as the national drink of both Peru and Chile. The historic tension between these two nations—based notably on the nineteenth‐century War of the Pacific—is used as a backdrop to understanding the cultural and political contestation over the “ownership” of this beverage. Although both countries see exportation of pisco as a means of agricultural development, much of the animosity of this trade dispute is couched in cultural and historical terms. International trade policies, including the use of geographical indications (labels of geographical origin) for the purposes of trademarking, and the physical geography that makes pisco production possible are discussed.     

中国与全球能源网络的互动逻辑与格局转变

当前中国正处于从油气时代向可再生能源时代转变的关键时期,中国能源需求结构和能源利用形式的变化决定了中国与全球能源的互动逻辑发生了深刻转变。为更好理解中国与全球的能源互动过程,本文探讨了全球能源互动的基本理论认知,并借助复杂网络、投入产出分析等技术方法分析了中国与全球能源互动格局及其变化。研究发现中国与全球能源互动的范围不断扩大,程度不断加深,从油气贸易到可再生能源贸易,从油气为主的投资到多元化能源品种的投资,从传统能源贸易到隐含能源贸易等方面,中国逐渐塑造了多元化的全球能源格局。主要结论为：① “多煤少油缺气”的能源生产结构和巨大的油气需求,决定了保障海外油气供应是中国与全球能源互动最直接的逻辑,互动区域主要集中在油气富集的国家和地区。② 随着可再生能源的发展,中国与全球能源互动逻辑从单纯的油气贸易转变为涉及可再生能源相关产品的贸易,凭借制造业优势,互动范围从油气富集的国家和地区拓展到全球拥有可再生能源发展和装机需求的国家,形成了覆盖全球主要国家和地区的可再生能源贸易新格局。③ 中国的海外能源投资目标从有限数量的东道国扩展到欧洲、东南亚等国家和地区,投资业务不仅局限在油气领域,也扩大到太阳能、风能和水能等可再生能源发电项目及电网等基础设施建设投资。④ 中国作为全球制造业大国和贸易大国,在全球化程度加深的背景下,部分能源隐含于全球生产网络和贸易网络中进行二次分配,中国与全球能源互动范围进一步拓展到与中国具有一般商品贸易关系的国家和地区,形成了全球“能源中枢”的功能。本文可为深刻认识中国与全球的能源互动关系,维护国家能源安全和参与全球能源经济治理提供理论视角与决策依据。     

Consumer involvement in fair trade and local food systems: delegation and empowerment regimes

Today, various types of fair trade systems propose new forms of relationships between producers and consumers. If several studies have provided accurate understandings of consumers’ motivations to buy fair trade products, the specific kinds of consumer involvement that are emphasized in those systems remain partly unknown. In France, controversies about the regulation and organization of fair trade with producers from Southern countries has led to broader debates about how consumers can best express their solidarity with producers. In these debates local food networks are often portrayed as good examples of fair trade and as having potential to redefine the role of the consumer in the marketplace (or in commercial relations). Based on examination of the type of mechanisms used to enrol consumers in local and fair trade networks, we have distinguished two main kinds of consumers’ involvement. The first one may be called “delegation” and is based on market mechanisms. The second one is called “empowerment” and is based on contractual mechanisms between consumers and producers and on the construction of collective choices. This latter kind of consumer involvement points out the capacity of alternative food networks to empower consumers in a more broadly political sense.

天津市水资源足迹趋势预测与动态调节

为解决区域水资源相对不足的问题,以天津市为例,从水足迹视角,根据其实际情况,综合运用自上而下和自下而上两种算法,从生产用水(第一产业、第二产业、第三产业)、生活用水、生态用水和污水排放等方面计算了2004—2009年水资源足迹情况,并运用精度较高的拟合函数对其未来几年水资源足迹量、人口数量分别进行了趋势预测,从而得到天津市人均水资源足迹处于下降趋势的结论,并针对这种趋势(2015年将降至617m3),建议从调整产业用水结构、转变虚拟水贸易策略、优化产品消费结构、提高三大产业污水排放达标率、建立水足迹定期监控和预警机制等方面进行动态调节。     

试谈排污交易削减非点源污染

主要介绍采用排污交易的方法削减非点源污染的实施方法、条件及其应用,重点讨论了太湖磷污染的削减对策,并进行了效益评估,认为排污交易是解决太湖富营养化问题的有效方法之一.     

北极航道的贸易替代效应与贸易互补效应分析

随着北极冰雪加速消融,北极航道在国际贸易运输中的关注度日益提升。文章采用理论模型进行分析,认为北极航道通过贸易替代效应与贸易互补效应对世界贸易格局产生影响。研究发现北极航道开通将：提升航道沿线各国间的贸易潜力,改变沿线国与非沿线国间部分贸易活动的流向;催生北极航道沿线国之间部分贸易活动的产生,改变北极航道沿线国之间部分贸易活动的流量。     

行政边界对城市群交界地区土地利用变化的影响——以通州—武清—廊坊地区为例

由于各地资源禀赋差异和各级政府之间的复杂关系,城市群交界地区不可避免地存在经济社会发展上的矛盾和不平衡。已有研究揭示了行政边界效应在省域、城市群等不同尺度均普遍存在,且在不同阶段影响土地利用变化的程度大小不一,但多将行政边界转化为虚拟变量而非空间地理要素,不足以理解中微观尺度各种因素之间的复杂相互作用。论文旨在利用1985—2020年的中国年度土地覆盖数据集,以区县为单元,运用质心迁移、核密度分析和Logistic回归方法,分析京津冀典型城市群交界地区“通州—武清—廊坊(通武廊)地区”不透水面(ISA)的扩张机理并测度行政边界效应的影响。结果显示：(1)不同行政区因资源禀赋和所处发展阶段的不同,城市用地扩张的速度和主要时期存在一定的差异;(2)由于要素的高度流动,地理邻近的行政区城市扩张驱动要素表现出一定的相似性;(3)在不同区域分工水平下,行政界线的边界效应对城市用地扩张的影响表现出一定差异性。通过“强—弱”管控提高通武廊地区各要素协调水平,减少行政边界对地方之间资源整合的负面影响,对于实现京津冀城市群协同发展具有重要作用。