Externalities,Floating Population and Spatial Agglomeration

Abstract

With the further development of socialist market economy, the mobility of factor markets in China, especially the labor market, is strengthened. Externalities interacts with the agglomeration of productive factors. Under the framework of new economic geography, this article presents a theoretical model involving the endogenous population density affected by urban externalities. Results show that the population density is more concentrated around the center because the degree and extent of interaction between individuals intensifies when the distance from the center decreases. When there are several externalities resources, the aggregation of externalities changes the configuration of spatial factor allocation. These results fit well with the empirical facts about the decreasing density of floating population along the cities of Guangzhou, Dongguan and Shenzhen in Guangdong Province which is situated in the eastern coast of the Pearl River Delta. We find that under the impacts of externalities released from Hong Kong into the coast, floating population was more concentrated around Shenzhen and Dongguan, which are more adjacent to Hong Kong compared with Guangzhou City.     

经济发达城市人口承载力预测及其经济合理性评价——以无锡市区为例

在经济发达地区资源环境约束趋紧和经济发展转型背景下，开展人口规模预测研究对协调人口、资源、经济之间的关系具有积极意义。以无锡市区为例，核算土地资源人口承载力与不同时间阶段经济合理人口规模，分析土地资源人口承载量与经济合理人口规模之间的关系，解析未来人口发展趋势和影响因素。结果表明：无锡市区人口仍将稳步增加，外来人口仍将是常住人口增量的主体，但增速趋缓；2015、2020年经济合理人口分别约为404万和434万人，逐渐超出土地资源承载力所确定的402万人的合理人口规模；经济增长引起的就业人口的需求增长是导致人口总量增长的主要因素。未来需要通过产业结构调整、劳动生产率提升、公共服务设施完善等手段调控人口发展，以减轻资源环境压力和保障经济发展     

香港典型地质遗迹资源与地质公园建设

香港素以金融、商业贸易中心闻名于世界,但香港境内所发育的曲折有致的岩石海岸、幽远宁静的海滩、巍峨多姿的群山、造型奇异的岛礁,弥足珍贵的自然生态和地质遗迹资源却鲜为人知。本文在对香港地质概况进行简单介绍的基础上,对香港地质遗迹资源进行系统分类和对比分析,指出西贡万宜水库至果洲群岛方圆近150 km2范围内发育的十分典型、极具规模的六方柱状节理构造景观是世界上同类岩石中罕见的地质现象,其分布面积大,露头完整,具有稀缺性、独特性和典型性,最后对香港国家地质公园一个公园,两个园区,八个景区的空间结构及每个园区的主要地质遗迹资源进行了系统归纳总结。香港国家地质公园的建立很好的起到了保育地质多样性的首要目标,同时很好地推动了香港的地质教育和科普发展。     

生态公益林建设管理的环境经济政策分析--以广州市为例

根据环境经济学的外部性理论 ,生态公益林建设管理具有外部经济性。使生态公益林建设管理外部性内部化的主要手段是“调节市场”型的环境经济政策 ,即由政府向公众征收生态公益林建设管理费用 ,而“建立市场”型的环境经济政策———明晰生态公益林的产权、承包经营权 ,则是生态公益林建设管理外部性内部化和生态公益林有效管理的需要。广州市生态公益林建设管理中存在的建设管理资金不足、林地的使用权分散、对林农补偿的数量难以确定等问题 ,有待于上述两种环境经济政策来解决     

Floating Population Increase and Its Influence on the Urban Population Situation:A Case Study in Beijing

1 BACKGROUND OF FLOATING POPULATIONIN CHINAChina's urbanization process was influenced mainly bythe government interventions before the adoption of thesocial and economic reform started in 1978. Since thefoundation of the People's Republic of China, thegovernment had strictly controlled the internal migration,especially from rural to urban areas. The ability of thegovernment to make a strong impact on the migrationand urbanization was realized by the household registrationsyste…     

长江三角洲地区人口空间演变特征及动力机制

研究区域人口空间演变,可揭示区域人口空间分布的规律性,对于制定合理的人口发展政策,促进区域的可持续发展,均具有重要意义。根据1982、1990、2000年人口普查资料,结合长江三角洲地区各市历年统计年鉴,先对本地区的人口分布空间格局进行了分析,得出各地市人口数量差异巨大、人口密度北高南低、沿交通轴线人口集中分布的特点,然后对20世纪80年代以来人口分布的动态变化特征、规律做了较细致探讨,得出各地区人口增幅存在较大差异、人口密度增长总体放缓、人口分布先集中后分散、人口重心由东北向西南移动等演变特征。并结合影响区域人口空间分布的外部因子进行解释,认为经济因素、城市地位与功能、政策因素以及信息交通等因素是造成本区人口空间结构发生巨大变化的原因。     

Floating Population Increase and Its Influence on the Urban Population Situation: A Case Study in Beijing

Abstract

Floating population is a special population group in China resulting from the implementation of household registration system. This paper uses a set of floating population survey data, population censuses data and statistical data to analyze the increase and influence of floating population on the urban population situations in Beijing. It is found that Beijing has experienced a rapid increase of floating population since the 1990s and that the increase of this group has become the key factor of the current population expansion in the city. Its distribution in the urban regions intensified and extended the suburbanization process of the capital. In addition, the population structures of sex, age, education and employment in Beijing have changed to some extent due to the influx of floating population.     

Mutagenicity, genotoxicity and carcinogenic risk assessment of indoor dust from three major cities around the Pearl River Delta

The mutagenicity and genotoxicity of workplace dust including commercial office, secondary school, shopping mall, hospital, electronics factory and manufacturing plant in Hong Kong and settled house dust from Hong Kong, Shenzhen and Guangzhou were measured. Results indicated that indoor dust contained both frameshift and base pair substitution mutagens. Dust from manufacturing plant showed highest mutagenic potency on TA98±S9 and TA100±S9 activation, whereas, electronics factory showed highest genotoxicity with and without S9 activation. TA100 (-S9) mutagenic potency was significantly correlated with genotoxicity expressed as SOSIP (-S9) of workplace dust (r(2)=0.37, p<0.01). The total PAHs concentration of settled house dust from PRD ranged from 1.63 to 29.2μg/g. Linear regression analyses indicated that the PAHs likely accounted for about 45% of the TA98 with S9 mutagenic activity of workplace dust. TA98 (-S9) mutagenicity (r(2)=0.27, p<0.05) and SOSIP (-S9) of house dust (r(2)=0.41, p<0.01) were both significantly correlated with the number of inhabitants in the house. To achieve a more accurate cancer risk assessment, the oral bioaccessibility of B(a)A, Chry, B(b+k)F, B(a)P, D(ah)A and I(cd)P in different dust ranging from 1.3% to 17% was taken into account. Risk assessments indicated that about 26% of house dust samples resulted in unacceptable cancer risk (>1×10(-6)) for preschool children.     

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运用空间自相关的全域指标和局域指标，分析1990年和2000年上海市域及中心城区两个年份的人口密度的Moran's I和Getis's G值。结果表明：从市域的尺度上看，10年间，人口集聚增强，即城市高密度集聚、农村低密度集聚，中心城区及其内部出现的人口密度相对分散的趋势只是表现在城市内部，而市域内城市与农村之间的差异仍在不断扩大，表现为一种从农村向城市的向心型城市化过程，而且城市化还处于不断上升的阶段。从中心城区的尺度看，10年间，中心城区人口密度不断降低，城区核心人口绝对量持续减少，城区外缘绝对量持续增加，上海市城区具有明显的郊区化特点，空间上表现出一种离心型城市化的特点。研究结果的可借鉴性表明空间自相关的统计分析能更好地揭示出人口的分布模式、人口集聚及其变化的热点和内在机制，对于人口的合理布局方案、城市化政策制定等政府宏观决策具有意义。     

1982～2010年湖北省人口分布格局变迁及其影响因素

以人口普查数据为基础,采用空间分析技术,对1982~2010年湖北省人口分布的变迁及原因进行研究。结果表明:(1)湖北省人口分布具有显著的空间差异:区域尺度上,人口分布由东向西梯度递减,且梯度差异不断扩大;地市尺度上,武汉市始终是人口密度最高的地区,神农架、恩施、十堰、宜昌始终是人口密度最低的地区;县级尺度上,人口两极分化明显;省域尺度上,人口密度高值区长期呈三足鼎立的态势,人口重心始终位于几何中心以东,并不断向东迁移;(2)湖北省人口格局形成的原因是多方面的:自然地理差异是奠定湖北人口分布格局的决定因子;社会经济发展对湖北人口分布在自然基础上进行再塑造;区域发展战略对湖北人口分布的变迁起着重要导向作用;开发历史也在一定程度上影响了人口分布的布局。     

中国碳市场波动溢出效应研究

自2013年以来,中国已先后建立了七个区域性碳市场。研究中国碳市场之间的波动溢出效应,有助于发现在碳市场运行初期起价格引导作用的区域市场,为其它地区碳市场的发展和全国碳市场的建立提供建议。本文选择广东、湖北和深圳三个交易量最大的区域碳市场为样本,利用多元GARCH(1,1)-BEKK模型,检验其波动溢出效应。为了消除履约期的影响,本文根据履约期将样本划分为阶段一(2014年7月1日—2015年6月30日)和阶段二(2015年7月1日—2016年7月19日),分阶段进行了检验,并从市场有效性的视角解释了检验结果。波动溢出效应检验结果显示:在阶段一内,广东碳市场对湖北碳市场、湖北碳市场对深圳碳市场、深圳碳市场对广东碳市场分别存在单向的波动溢出效应;在阶段二内,只存在深圳碳市场对广东碳市场的单向波动溢出效应;在整个样本期内,只存在深圳碳市场对广东碳市场的单向波动溢出效应。基于方差比的市场有效性检验结果显示:无论是阶段一、阶段二或整个样本期,三个碳市场均没有达到弱式有效。本文进一步在多重分形检验的基础上,利用多重分形谱宽度,比较了三个碳市场的非有效性程度,结果显示:在阶段一、阶段二和整个样本期,三个碳市场有效性大小关系分别为:湖北广东深圳、深圳湖北广东、广东深圳湖北。可见,三个碳市场早期的波动溢出效应不完全符合市场有效性大小关系,而较晚期的波动溢出效应符合市场有效性大小关系,这证明了中国碳市场在阶段二相比阶段一更为成熟。本文最后对中国碳排放权交易市场的发展提出了政策建议。     

苏州市与温州市不同经济模式下流动人口的空间特征比较

我国正经历着一个巨大的人口流动潮，其主要流向是中西部向东部发达地区流动，农村地区向城镇密集的大中城市地区流动。发达地区的经济模式不尽相同。不同模式下地区流动人口的流向也存在着一定差异。分析比较不同发达地区的流动人口特征，对当地经济政策、产业定位、管理制度等方面均有着非常重要的指导作用。以发达地区流动人口的空间特征为研究目标，以最具代表性的“苏南模式”的苏州市和“温州模式”的温州市两个城市作为研究对象，比较总结两城市的流动人口空间特征与差异，可以看出：苏州市以人口流入为主，温州市流入流出人口数量持平；苏州市吸引外来人口的范围不如温州市广；苏州市城市中流动人口所占比例高过温州市。此外，还对不同经济模式下流动人口空间特征对地区经济发展产生的影响进行了总结，并且给出结论，以期能够对地区的经济发展起到一定的指导和促进作用。     

市场结构与环境污染外部性治理

本文运用产业组织理论分析环境污染所带来的福利影响,与传统经济理论形成鲜明的对照,为治理环境污染提供新的解决思路.虽然在大多数情况下完全竞争优于完全垄断,但是如果发生了市场失灵,对整个社会来说完全垄断就优于完全竞争.为此,本文针对不完全竞争市场结构的现实,进一步深入探讨环境污染外部性的福利效果,重新考察庇古税和科斯定理作用的约束条件.虽然我们依据完全竞争市场与负外部性会得到产生过多污染的结论,其解决方法是征收等于外部性的边际社会成本的税收,但这并不适用于不完全竞争市场,甚至是错误的.因此从负外部性角度看,我们发现不竞争市场结构可能产生高于或低于社会最优水平的产出和污染,虽然通过征税让企业负外部性内部化,竞争性市场的产量就是社会最优的水平,但这并不适合不完全竞争市场.因此,我们只有将市场势力、产权和庇古税有机结合起来,才能更现实地解决环境污染的负外部性问题,这对实现国民经济全面、协调与可持续发展具有非常重要的意义.     

Spatial correlation network and population mobility effect of regional haze pollution: empirical evidence from Pearl River Delta urban agglomeration in China

Based on relevant data from 2014 to 2018, we constructed a spatial network of haze pollution in the Pearl River Delta (PRD) region by using a modified gravity model, explored the network structure characteristics and influencing factors of urban agglomeration with the SNA and the QAP method, and discussed the population mobility effect brought by haze pollution. The results showed that the PRD region has spatial correlation in terms of haze pollution. Guangzhou was in the central position of the spatial network, yet Shenzhen and Foshan played a connecting role in the network. Economic development, urbanization, and environmental protection had significant positive impacts on the haze pollution spatial network. The results of the double-threshold regression showed that the city’s status in the haze pollution network represented by centrality had a positive impact on population mobility.

     

Vulnerability assessment of sea-level rise in Viti Levu, Fiji Islands

Fiji is expected to come under increasing pressure and risk from various threats resulting from climate change and sea-level rise (SLR). Fiji consists of 332 islands and thus has a predominant and large coastline. Viti Levu is the largest and most important of the islands, harboring Fiji’s capital city and most of the major towns concentrated around its coast. The objectives of this study were to evaluate the extent of possible sea-level rise using GIS, and to identify high-risk locations. Potential sea level rise was shown graphically as an output to determine where inundation or flooding would take place. This analysis allowed important areas facing risk to be highlighted for future action. Flooding/inundation can be classified into two kinds: ‘permanent inundation’, which is the result of sea-level rise with tide; and ‘temporary flooding’, also including occasional storm surge events. The inundated area was displayed under different projections and quantified. The results produced output maps showing the distribution of inundation/flooding around the island of Viti Levu as well as the extent of flooding. Six scenarios for sea-level rise were used (0.09, 0.18, 0.48, 0.50, 0.59, 0.88 m). Six scenarios for storm surge were used with return intervals of 1, 2, 5, 10, 25, 50 years. High risk and priority locations are identified as Fiji’s capital Suva, the major tourist center and arrival port of Nadi, and Fiji’s second city Lautoka. Future action, adaptation and response strategies in these identified locations must occur to reduce risk from climate change.     

Distribution of PBDEs in air particles from an electronic waste recycling site compared with Guangzhou and Hong Kong, South China

Air samples of total suspended particles (TSP, particles less than 30-60 microm), and particles with aerodynamic diameter smaller than 2.5 microm (PM(2.5)) were collected simultaneously at Guiyu (an electronic waste recycling site), three urban sites in Hong Kong and two urban sites in Guangzhou, South China from 16 August to 17 September 2004. Twenty-two PBDE congeners (BDE-3, -7, -15, -17, -28, -49, -71, -47, -66, -77, -100, -119, -99, -85, -126, -154, -153, -138, -156, -184, -183, -191) in TSP and PM(2.5) were measured. The results showed that the overall average concentrations of TSP and PM(2.5) collected at Guiyu were 124 and 62.1 microg m(-3), respectively. The monthly concentrations of the sum of 22 BDE congeners contained in TSP and PM(2.5) at Guiyu were 21.5 and 16.6 ng m(-3), with 74.5 and 84.3%, contributed by nine congeners (BDE-28, -47, -66, -100, -99, -154, -153, -183 and -191 respectively). This pattern was similar to Tsuen Wan site of Hong Kong. Two urban sites of Guangzhou had the same congener pattern, but were different from Yuen Long and Hok Tsui sites of Hong Kong. The results also showed that the amount of mono to penta brominated congeners, which are more toxic, accounted for 79.4-95.6% of Sigma(22)PBDEs from all sites. All congeners tested in Guiyu were up to 58-691 times higher than the other urban sites and more than 100 times higher than other studies reported elsewhere. The higher concentration in the air was due to heating or opening burning of electronic waste since PBDEs are formed when plastics containing brominated flame retardants are heated.     

Monitoring of emissions from selected trades and industries in Hong Kong

A survey on the concentration of organic and inorganic compounds emitted from various trades and industries in Hong Kong was performed to indicate the level of pollutants occuring in the factories, in the stacks and their dispersion into the environment. The results indicate that none of the organic or inorganic compounds present in the workplace exceed the TLV value for the factories during the visit in the two years period of study. However, the concentration of the chemistry compounds in the stack are found to be very high, with NH₃ and HCl exceeding the emission limits. As the dispersion of pollutants in a highly populated place like Hong Kong is an important concern, the effect of prominent stationary sources on the nearby population were investigated qualitatively to establish their contribution to the pollution level at the receptor site in addition to the background pollutant level. Due to the lack of input meteorological data and the highly complex topology around most sites amongst high-rise buildings in Hong Kong, it is difficult to use advanced computer model dealing with complex terrain. Instead, a simple impaction formula was tested for its applicability in Hong Kong. The results indicate an over estimation of the experimental value. Nevertheless, it could be used to provide a rough estimate of the upper limit of the pollutant concentration at given receptor sites. The feasibility of assessing the contribution or different stationary sources to the particulate collected at given receptor sites was studied and work is in progress to obtain a more comprehensive pollutant data inventory for the above assessment.     

粤深碳交易试点机制剖析及对国家碳市场建设的启示

广东和深圳是中国第一批碳交易试点地区,具有全国碳交易机制试验田的属性,研究粤深碳交易试点机制运行经验对全国碳市场建设有重要的借鉴意义。对广东和深圳碳交易机制的关键要素进行剖析与比较发现,两地碳交易机制在覆盖范围、配额总量、分配方案、MRV机制等方面有较大的不同。这些差异来源于两个方面:第一,碳交易机制的排放管理设计特点(覆盖范围、配额总量、分配方案、MRV机制)取决于地方的区位条件和政策目标。粤深经济规模和结构差异较大,由此导致两地碳交易机制的管理对象不同,管理对象的行业特征又决定了其他管理要素必然随之发生变化。第二,碳市场运行状态受碳排放管理要素的影响:当配额总量较紧、允许使用的碳抵消比例低、惩罚严苛时,碳市场交易相对活跃,更容易催生碳金融等衍生品市场。在对粤深碳交易机制的运行情况和特点进行深入分析后,得到如下启示:1配额有偿分配制度应循序渐进地实施,收紧配额总量是关键。应根据碳交易机制对不同行业竞争力的影响程度确定免费配额的比例;2分配给企业的配额量与节能考核目标衔接,保持相关环境管理政策的一致性,减少制度摩擦;3正确处理由产量变化和经济波动对配额分配带来的影响,保持配额分配标准的公平与统一;4稳定公众预期是促进碳交易机制正常运行的关键要素之一;5对未纳入碳交易机制的碳排放行为进行约束,有助于实现社会公平;6提高企业与第三方机构相关人员的专业技能水平,增强碳排放数据可靠性。     

长江中游城市群人口分布与城镇化格局及其演化特征

城市群日益成为我国人口集聚和城镇化发展的重要载体,2015年4月《长江中游城市群发展规划》的提出标志着长江中游城市群建设正式上升为国家发展战略。基于2014年长江中游城市群人口和城镇化格局现状分析,采用湘鄂赣3省第四、五、六次人口普查数据,分析了1990~2010年长江中游城市群人口与城镇化格局的空间变化。研究发现:(1)1990~2010年,长江中游城市群人口分布不均衡,武汉、长沙、南昌3大省会城市一直是人口的主要集中地,人口集聚水平不断提升,但城市群整体的人口集聚水平有所下降,人口分布的空间格局呈现出由单核心结构向多核心结构的发展趋势;(2)人口"镇"化是长江中游城市群城镇化发展的主要驱动力,城镇化水平经历了由以长江为界北高南低分布向沿长江、京九和浙赣沿线地区分布的发展过程,形成了多核心结构的城镇化格局;(3)对比人口分布与城镇化格局的演变过程,反映出人口集聚度对城镇化格局的形成有着重要影响,但区域城镇化同时受到经济发展水平、工业化水平、基础设施等多种因素影响,其格局变化更加复杂、显著。     

江苏省大气气溶胶光学厚度时空分布研究

气溶胶光学厚度（AOD）是气溶胶总含量的基本参数，可以用来反映大气污染程度。利用卫星遥感获取气溶胶光学厚度,可以弥补地面观测难以反映AOD空间分布和整体变化趋势的不足。以江苏省为例，利用2010年4~9月EOS TERRA MODIS数据，分别基于暗像元法（DDV法）和改进的暗像元法（V52法），反演研究区2010年夏半年/春夏两季气溶胶光学厚度，并结合地面观测数据验证两种反演算法结果精度，最后分析研究区AOD时空变化特征。研究结果表明：在研究区，两种算法反演结果在整体趋势上保持一致，研究区AOD均表现出与植被指数NDVI较为明显的负相关关系，但V52法反演精度要明显优于DDV法；研究区气溶胶光学厚度存在较明显的区域差异和季节变化，具体表现为苏南AOD明显高于苏中、苏北地区，而在春、夏两个不同季节上，不同区域变化趋势不同，苏南地区春季AOD高于夏季，而在苏北地区则刚好相反，夏季AOD要高于春季