长江经济带物流业集聚的时空格局与影响因素研究

物流产业集聚对提高物流效率、发挥溢出效应具有重要作用,提高物流产业集聚水平是提升区域内竞争力的关键。基于2006—2015年长江经济带省际面板数据,研究了长江经济带物流集聚的时空格局及其影响因素。结果表明:(1)下游地区物流集聚水平呈下滑趋势,上游地区呈上升趋势,中游地区则具有空间锁定和路径依赖性,物流集聚水平相对平稳;(2)研究期间,长江经济带物流产业集聚的层次异质性得到弱化,但局域异质性凸显出来;(3)所选因素均对本地物流集聚产生了促进作用,其中工业增加值和社会消费水平对物流集聚的推动作用最大,而各因素对周边地区物流集聚主要起到负溢出效应,总体上"回流效应"大于"扩散效应"。     

长江经济带绿色城镇化效率评价及其影响因素——基于多维城镇化视角

本文引入资源和环境因素，以城镇化综合指数为期望产出，运用SBM方向性距离函数测算了2010-2020年长江经济带112个地级市（州）的绿色城镇化效率，并采用空间面板模型和地理探测器对绿色城镇化效率的影响因素进行实证分析。结果表明：长江经济带绿色城镇化效率整体水平不高，下游地区绿色城镇化效率高于上游和中游地区，资源消耗和环境污染是效率损失的主要来源；绿色城镇化效率表现出较为明显的热点-次热点-次冷点-冷点自东向西的带状分布格局，存在显著的空间正相关性。政府财政支出对绿色城镇化效率产生负向影响，外商直接投资和产业结构对提升绿色城镇化效率有显著的促进作用，且三者的影响具有地区差异性；市场力因素有利于绿色城镇化效率的提高。邻近城市间绿色城镇化效率的空间溢出效应明显，且空间溢出效应是长江经济带绿色城镇化效率空间差异的最主要因素，各因素的影响具有协同增强的作用。     

长江经济带经济高质量发展差异性机理及对策分析

基于驱动力—压力—状态—影响—响应(DPSIR)模型,建立经济高质量发展系统作用机理分析框架和概念模型,运用结构方程模型对长江经济带上、中、下游三大区域经济高质量发展路径和关键因素进行探索。结果表明:①长江经济带下游地区作用机理为"驱动力—压力—状态—影响—响应"单向链式作用路径,资源消耗强度、贫困差异和生态环境质量为最关键因素。②长江经济带中游地区为"驱动力—压力—状态"和"影响—响应"跳跃式作用路径,产业结构为最关键因素。③长江经济带上游地区为"状态—影响—响应"的中断式作用路径,生态资源、科技创新和城市化为最关键因素。     

长江经济带能源消费碳排放的多变量驱动因素研究——基于扩展STIRPAT模型

采用我国长江经济带1995—2016年省域面板数据,基于扩展STIRPAT模型定量分析了长江经济带能源消费碳排放各驱动因素的影响机理。研究结果表明:(1)城市化水平因素对我国东部地区具有负向抑制作用,而对中部和西部地区具有正向驱动作用。(2)碳排放与人均GDP因素之间存在着倒"U"型曲线关系,目前只有东部地区通过了碳排放拐点,中部地区接近拐点,而西部地区碳排放量在较长时期内将持续增长。(3)产业结构和能源强度因素对碳排放均产生显著影响,且对中部和西部地区的影响远远大于东部地区,创新水平对碳排放影响微弱。(4)外商直接投资与金融发展因素对碳排放具有负向抑制作用,贸易开放度和环境规制因素的影响较小。     

基于EBM模型的长江经济带工业用水效率时空差异及影响因素分析

工业化进程的加快使得工业水资源需求不断增加，工业废水排放量也越来越大，如何提高工业用水效率从而缓解水资源压力成为日益严峻的问题。本文选取工业用水量、工业就业人数、工业固定资本和工业废水治理费用作为投入指标，以工业增加值与工业废水排放量作为期望与非期望产出指标。首先利用EBM模型计算长江经济带2008—2017年工业用水效率，其次利用泰尔指数来分析工业用水效率的区域差距，最后利用面板Tobit模型来分析影响不同地区工业用水效率的驱动因素。结果显示，近年来长江经济带的工业用水效率呈波动下降趋势，不同地区效率差异明显；经济发展水平、工业化程度、技术水平、水资源禀赋和政府环境管制力度对长江经济带的工业用水效率都有一定影响，但存在地区差异。     

长江经济带能源生态足迹空间效应分析——基于区域分工视角

考虑到全国工业主体长江经济带的生态足迹赤字较大且产业间同质化现象严重的问题,将较少涉及的区域分工因素纳入到空间模型分析框架,以探究人均能源生态足迹影响因素的空间效应。结果表明:(1)虽然我国长江经济带各省市人均能源生态足迹呈逐年上升趋势,但能源足迹强度和产值变化状况表明长江经济带能源利用的集约度在增强;(2)长江经济带人均能源生态足迹呈空间正相关关系;(3)长江经济带区域分工对人均能源生态足迹具有抑制作用,而其他控制变量则具有促进作用,其中人均GDP对人均能源生态足迹增长的贡献度最高;(4)长江经济带城镇化率、人均GDP和单位规模以上工业企业拥有的有效专利数三方面均存在着正向溢出效应。     

长江经济带污水处理设施减排效率与影响因素研究

污水处理设施作为废水排放的处理终端,在区域水环境治理的过程中发挥关键作用。本文以长江经济带沿线1117座污水处理设施为样本,以单位污水处理能耗作为污水处理设施的投入变量,BOD5等污染物的削减率作为产出变量,在考虑各类污染物对环境造成的异质性影响下利用WSBM模型对污水处理设施的减排效率进行测度,并运用CLAD模型对影响污水处理设施减排效率的外部因素进行研究。结果表明:长江经济带污水处理设施综合减排效率较低且差异较大,设施单位污水处理能耗冗余率较高以及对总磷污染物减排效果不理想是制约其减排效率提高的重要因素;长江经济带污水处理设施的减排纯技术效率总体呈现"东高西低",以上海、湖南、云南三省份形成"三极"的空间分布特征,而设施减排规模效率则呈现出"中部高、东西低"的空间分布格局;设施减排效率外部影响因素的驱动效应差异明显,并据此提出了排水管网合理规划、推进新型城镇化建设等对策建议。     

长江经济带工业废气污染治理效率的时空演变及其影响因素研究

本文选取1998—2015年30个省份数据,采用超效率SBM模型测算全国、长江经济带工业废气污染治理效率;采用门槛效应模型研判长江经济带工业废气污染治理效率的影响因素.研究发现:1998—2015年长江经济带工业废气污染治理效率大于全国工业废气污染治理效率;长江经济带工业废气污染治理效率与全国工业废气污染治理效率的演变轨迹相似;长江经济带工业废气污染治理效率空间格局从"两极分化型"向"过渡型"演变;长江经济带沿线11省份工业废气污染治理效率与重工业占比呈负相关;当人均GDP较小时,长江经济带工业废气污染治理效率与工业化率、地方法规颁布件数、环境污染与破坏总次数呈负相关,与群众因污染来信数呈正相关;当人均GDP跨过门槛阈值拐点后,相关关系反之.为进一步推动长江经济带高质量发展,应加强中央与地方政府合作共促工业污染防控治理,推动重化工业绿色发展,加强媒体对废气污染的长期有效监督,推动建立科学有效的"三方共治"体系.     

基于环境效应的“丝绸之路经济带”全要素能源效率研究——基于中国段17个城市的实证分析

采用"多投入—多产出"的DEA模型,以环境生产函数和方向性距离函数为基础,将污染变量作为坏产出而引入生产函数,在传统生产技术的基础上构造出环境生产技术,对丝绸之路经济带(中国段)17个城市2000—2014年全要素能源效率、成分、影响因素进行测度与分析。研究表明:在环境约束下能源过度使用、废气过度排放导致丝绸之路经济带(中国段)各城市能源效率增长率和能源使用技术效率增长率降低。同时,因为忽视能源减排技术,导致能源使用技术进步增长率降低。因此,通过提高能源利用效率、强化节能减排技术利用、调整产业结构、抑制高能耗行业过快增长、加强丝路沿线城市技术交流与合作等举措有助于提高各城市的全要素能源效率,最终实现丝绸之路经济带的经济增长与能耗降低。     

环境规制对城市生态技术扩散效率的影响研究

生态技术扩散是长江经济带生态文明建设的必要环节，也是企业履行环保责任的有效措施。本文以长江经济带110个地级及以上城市为研究对象，采用非径向方向距离函数对城市工业企业生态技术扩散效率进行测算，分别从整体和区域异质性角度实证分析环境规制对城市工业企业生态技术扩散效率的影响及内在机理。结果表明：长江经济带城市环境规制与生态技术扩散效率存在倒“ U”形关系，环境规制对生态技术扩散效率还存在多重影响路径，外商直接投资和工业集聚在影响路径中分别起着中介作用，且外商直接投资和工业集聚的链式中介显著。在异质性分析中，发现环境规制、外商直接投资、工业集聚和生态技术扩散效率之间的关系因区域位置不同而存在差异性。为此，依据研究结论及环境规制实施现状提出相应的政策建议，实现长江经济带经济永续绿色发展目标。     

BIOLOGICAL INDICATORS AND BIOLOGICAL EFFECTS OF ESTUARINE/COASTAL POLLUTION1

ABSTRACT: Sustained interest in and concern about the health status of the aquatic environment has resulted in extensive research focused on (1) effects of pollution on survival, growth, and reproduction of resource species at all life stages; (2) diseases of fish and shellfish, as they may be related to pollution and as they may serve as indicators of environmental stress; and (3) contaminant body burdens in fish and shellfish - their effects on the aquatic animals and their potential effects on humans. Effects, lethal and sublethal, of pollutants on life history stages of fish and shellfish have been documented, as have impacts on local stocks in badly degraded habitats, but as yet there has been no adequate quantitative demonstration of effects on entire aquatic species - probably because of the difficulty in sorting out relative effects of the many environmental factors that influence abundance. Sublethal effects, especially those that result in disease, have been examined intensively, and some diseases and disease syndromes have been associated statistically with pollution. Other pollution indicators (biochemical, physiological, genetic, behavioral, and ecological) have also received some attention, as have body burdens of contaminants in aquatic species. Research, especially that conducted during the past decade, has done much to clarify the many pathways and toxic effects of contaminants on aquatic animals, and has also helped to identify mechanisms for survival of fish and shellfish in the presence of environmental changes caused by human activities.     

Definition Procedures Have Little Effect on Performance of Environmental Classifications of Streams and Rivers

Mapped environmental classifications are defined using various procedures, but there has been little evaluation of the differences in their ability to discriminate variation in independent ecological characteristics. We tested the performance of environmental classifications of the streams and rivers of France that had been defined from the same environmental data using geographic regionalization and numerical classification of individual river valley segments. Test data comprised invertebrate assemblages, water chemistry, and hydrological indexes obtained from sites throughout France. Classification performance was measured by analysis of similarity (ANOSIM). Geometric regions defined by a regular grid and without regard to environmental variables and a posteriori classifications based on clustering the test datasets defined lower and upper bounds of performance for a given number of classes. Differences in classification performances were generally small. The ANOSIM statistics for the a posteriori classifications were around twice that of all environmental classifications, including geometrically defined regions. The hydro-ecoregions performed slightly better for the invertebrate data and the network classification performed slightly better for the chemistry and hydrological data. Our results indicate that environmental classifications that are defined using different procedures can be comparable in terms of their ability to discriminate variation of ecological characteristics and that alleged differences in performance arising from different classification procedures can be small relative to unexplained variation. We conclude that definition procedures might have little effect on the performance of large-scale environmental classifications and decisions over which procedures to use should be based primarily on pragmatic considerations.     

Journalists' views of advertiser pressures on agricultural news

All major journalism ethical codes explicitly state that journalists should protect editorial copy from undue influence by outside sources. However, much of the previous research on agricultural information has concentrated on what information various media communicate (gatekeeping studies) or communication's role in increasing innovation adoption (diffusion studies). Few studies have concentrated specifically on organizational and structural constraints that might adversely affect agricultural journalists' ethical standards; those that have, focus largely on farm magazines. A study of newspaper reporters who cover agricultural news found that the most pressing ethical concern is the effect of advertiser (agri-business) pressure on editorial copy, and that their concerns in general parallel those of farm magazine writers and editors. The majority reported being in situations in which they might be exposed to advertiser pressure, including pressures to change or withhold editorial copy. Large minorities suggested that advertising pressures affect the overall environment in which agricultural journalists work, and more than one in ten said they allow advertiser pressures to influence editorial decisions. The newspaper reporters who cover agricultural beats showed slightly more resistance to advertiser pressure than did farm magazine editors in a parallel study.     

Effect of Light on Biodegradation of Estrone, 17β‐Estradiol,and 17α‐Ethinylestradiol in Stream Sediment

Biodegradation of [A‐ring ¹⁴C] Estrone (E1), 17β‐estradiol (E2), and 17α‐ethinylestradiol (EE2) to ¹⁴CO₂ was investigated under light and dark conditions in microcosms containing epilithon or sediment collected from Boulder Creek, Colorado. Mineralization of the estrogen A‐ring was observed in all sediment treatments, but not epilithon treatments. No difference in net mineralization between light and dark treatments was observed for ¹⁴C‐E2. Net mineralization of ¹⁴C‐E1 and ¹⁴C‐EE2 was enhanced in light treatments. Extents of ¹⁴CO₂ accumulation and rates of mineralization were significantly greater for E2 than E1 under dark conditions, but were comparable under light conditions. These results indicate substantial differences in the uptake and metabolism of E1 and E2 in the environment and suggest biorecalcitrance of E1 relative to E2 in light‐limited environments. The extent of ¹⁴CO₂ accumulation and rate of mineralization for EE2 in dark treatments were less than half of that observed for E2 and generally lower than for E1, consistent with previous reports of EE2 biorecalcitrance. However, ¹⁴CO₂ accumulation and rates of mineralization were comparable for EE2, E2, and E1 under light conditions. These results indicate photoactivation and/or phototransformation/photodegradation processes can substantially enhance heterotrophic biodegradation of estrogens in sunlit environments and may play an important role in estrogen transport and attenuation.     

Bioremediation of Soils by Plant–Microbe Systems

Abstract

Sustainable ecosystems can be designed to eliminate environmental toxins and reduce pathogen loads through the direct and indirect consequences of plant and microbial activities. We present an approach to the bioremediation of disturbed environments, focusing on petroleum hydrocarbon (PHC) contaminants. Treatment consists of incorporating a plant-based amendment to enhance ecosystem productivity and physiochemical degradation followed by the establishment of plants to serve as oxidizers and foundations for microbial communities. Promising amendments for widespread use are entire plants of the water fern Azolla and seed meal of Brassica napus (rapeseed). An inexpensive byproduct from the manufacture of biodiesel and lubricants, rapeseed meal is high in nitrogen (6% wt/wt), stimulates >100-fold increases in populations of resident Streptomyces species, and suppresses fungal infection of roots subsequently cultivated in the amended soil. Synergistic enzymatic and chemical activities of plant and microbial metabolism in root zones transform and degrade soil contaminants. Emphasis is given to mechanisms that enable PHC functionalization via reactive molecular species.     

Energetics and environmental costs of agriculture in a dry tropical region of India

The present article, based on a study of five village ecosystems, assesses the energy efficiency of rain-fed agriculture in a dry tropical environment and the impact of agricultural activity on the surrounding natural ecosystems. Agronomic yield is insufficient to meet the food requirement of the human population, hence 11.5%–49.7% of the required amount of food grains are imported from the market. Energy requirements of five studied agroecosystems are subsidized considerably by the surrounding forest in the form of fodder and firewood. Natural ecosystems supply about 80%–95% of fodder needs and 81%–100% of fuelwood needs. The output-input ratio of agriculture indicated that, on average, 4.1 units of energy are expended to obtain one unit of agronomic energy. Of this, 3.9 units are supplied by the natural ecosystem. In addition, 38% of the extracted firewood is marketed. The illegal felling and lopping of trees result in ever-increasing concentric circles of forest destruction around the villages and together with excessive grazing results in savannization. The forests can be conserved by encouraging fuelwood plantations (0.7 ha/ha cultivated land) and developing village pastures (1.6 ha/ha cultivated land) and reducing the livestock numbers. Agricultural production in the region can be stabilized by introducing improved dry farming techniques such as intercropping, planned rainwater management, and adequate use of fertilizers.     

WHAT DO WE MEAN BY “METROPOLITAN WATER MANAGEMENT INSTITUTIONS?”1

ABSTRACT The term “institution” and several variants are used frequently in the literature on metropolitan water management. The state-of-the art investigation on which this paper is based revealed that 1) many uses of the term do not include careful definitions; 2) many users of the term seemed unaware of the general, theoretical literature on the subject of institutions; 3) there was little consistency among uses, either in the practical literature dealing with water or in the conceptual literature dealing with theories of institutions or institutionalization; 4) some usages were without significant meaning; 5) in many cases the term was used as a kind of “black box” to account for behavioral, societal, or managerial factors; 6) the term was often used as a synonym for “organization”. This latter use is frequently found in federal reports, including National Water Commission studies, and is most unfortunate because it tends to slight significant social-psychological factors. A suggested definition is: “An institution is the structured result or outcome of a process by which values are articulated, arranged, and communicated, having continuity over time, and influencing behavior of persons who did not necessarily participate in formulating those values (norms).”     

Waste minimisation in practice

One of the major hindrances to waste minimisation on a construction site is the difficulty in establishing a methodology and using this methodology to benchmark future construction projects. This paper introduces SMARTWaste, a software tool that has been used to audit, reduce and target waste arisings on a construction site. This tool tries to link the construction process and the waste hierarchy. That is reducing waste on a construction site rather than landfilling it. Three applications of the SMARTWaste software will be discussed using case studies from three different types of construction. An evaluation of these case studies shows that, by implementing a waste minimisation scheme on-site, you can improve material recovery for reuse. Also, by using the waste arisings as a benchmark you can reduce your waste arisings on future sites. Application of SMARTWaste or a similar waste minimisation tool on a wider basis could reduce waste arisings and could result in a built environment that consumed less natural resources and energy, and also produced less pollution and waste. Such a built environment would be environmentally and socially more responsive and responsible.     

COMPARISON OF TRACE ELEMENT CONCENTRATIONS IN TISSUE OF COMMON CARP AND IMPLICATIONS FOR MONITORING1

Common carp (Cyprinus carpio) collected from four sites in the Red River of the North in 1994 were analyzed for arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), selenium (So), and zinc (Zn). Concentrations differed among liver, muscle, and whole body. Generally, trace element concentrations were the greatest in livers while concentrations in whole bodies were greater than those in muscle for Cd, Cu, Ni, Pb, and Zn, and concentrations in muscle were similar to whole body for As and Se. Concentrations of Cr were lower in liver than either muscle or whole body. Correlations between liver and whole body concentrations were stronger than those between liver and muscle concentrations, but the strongest correlations were between muscle and whole body concentrations. Examination of tissue concentrations by collection sites suggested that, for a general survey, the whole body may be the most effective matrix to analyze.     

Macroalgal Introductions by Hull Fouling on Recreational Vessels: Seaweeds and Sailors

Macroalgal invasions in coastal areas have been a growing concern during the past decade. The present study aimed to assess the role of hull fouling on recreational yachts as a vector for macroalgal introductions. Questionnaire and hull surveys were carried out in marinas in France and Spain. The questionnaires revealed that the majority of yacht owners are aware of seaweed introductions, usually undertake short range journeys, dry dock their boat at least once a year, and use antifouling paints. The hull survey showed that many in-service yachts were completely free of macroalgae. When present, fouling assemblages consisted mainly of one to two macroalgal species. The most commonly found species was the tolerant green seaweed Ulva flexuosa. Most of the other species found are also cosmopolitan and opportunistic. A few nonnative and potentially invasive Ceramiales (Rhodophyta) were found occasionally on in-service yachts. On the basis of the information gathered during interviews of yacht owners in the surveyed area, these occurrences are likely to be uncommon. However they can pose a significant risk of primary or secondary introductions of alien macroalgal species, especially in the light of the increase in yachting activities. With large numbers of recreational yachts and relatively rare occurrences of nonnative species on hulls, comprehensive screening programs do not seem justified or practical. The risks of transferring nonnative species may, however, be minimized by encouraging the behaviors that prevent fouling on hulls and by taking action against neglected boats before they can act as vectors.