Greenhouse gas emissions along the rural-urban gradient

This paper investigates how land use relates to greenhouse gas emissions, using data sources that are readily available to municipal planners. It presents a causal framework linking settlement patterns to greenhouse gas emissions via landscape impacts (deforestation, carbon sequestration by soils and plants, urban heat island), infrastructure impacts (transportation-related emissions, waste management-related emissions, electric transmission and distribution losses) and buildings (residential, commercial). This is not a full accounting because it does not include impacts from industrial activities, agriculture and consumer behavior not related to land use, such as food consumption and air travel. Exploratory case studies of municipalities lying along a gradient of increasing population density suggest that per-capita carbon dioxide emissions vary widely, following an inverted ‘U’ shape, with post-war suburbs riding the pinnacle. Reflecting their central regional roles, municipalities with good jobs-to-housing ratios have higher per-capita emissions because they host both residential and commercial buildings. Buildings typically contribute more emissions than personal transportation. Vehicle-miles traveled per capita shrink most dramatically at very high population densities and where transit options exist. Changing land-use patterns is a political challenge because localism and outdated zoning ordinances subvert regional solutions. Technical fixes, especially green buildings, must be part of the solution.     

大型水电工程胁迫下川西高山地区土地整理模式——以甘孜州泸定县为例

探讨在大型水电工程相继修建的前提下的川西高山地区土地开发整理模式,做到有效增加耕地面积,提高土地利用效率,妥善安置移民。采取实证研究和规范研究相结合的方法进行研究。研究结果表明,川西高山地区土地整理模式可采用工程防护模式、开发未利用地模式、生物工程模式和土地平整模式等。川西高山地区土地整理必须突破水利设施、土壤改造和施工条件差等3项限制性因素,从土地整理的社会效益、经济效益和生态效益的综合体进行整体效益评价。     

广东沿海风暴潮灾害应急管理初探

广东沿海由于特殊的地理位置和气候条件,是风暴潮灾害的高发区。在分析广东沿海风暴潮灾害特点、广东省风暴潮灾害防御体系建设现状的基础上,总结了广东沿海风暴潮灾害应急管理中存在的问题,并提出了相应的对策和建议,可供工程技术人员和政府管理人员参考。     

全球视角下的企业ESG绩效驱动因素解析

企业是践行可持续理念、实现可持续发展目标的重要主体。企业需要在生产经营过程中统筹提升环境（E）、社会（S）、治理（G）三个维度的ESG绩效。基于外部压力和内部实力,本文预先设定了国家背景、行业属性、金融实力三种因素驱动企业改善ESG绩效的理论假设。为检验假设,本文使用多元线性回归和多层线性模型对来自55个国家、共计6139家上市公司样本进行实证研究。结果表明,即使在控制企业规模、风险管理和社会声誉的情况下,国家可持续发展水平、行业绿色发展水平、企业金融实力仍能显著提升企业ESG绩效。其中,国家和行业变量不仅直接促进了企业ESG绩效的提升,还在更高维度上通过调节CFP-ESG的关系间接促进企业ESG绩效的提升。本研究有助于企业更好地制定实施可持续发展战略,也能为投资者评估并筛选出ESG绩效优异的企业提供科学参考。     

长江三角洲全球城市区空间建构

在全球化背景下,全球城市区作为一种新的城市空间和功能组织形式,通过全球城市接入全球经济网络,在全球城市体系中发挥着越来越重要的作用。通过分析长江三角洲地区不断深入的全球化进程和不断加强的城镇一体化态势,提出长江三角洲地区是中国最有可能建设成为全球城市区的区域;进而从全球城市区的空间建构和功能组织的角度,提出通过提升上海全球城市功能,打造南京、杭州、苏州、宁波的次级全球城市职能,强化城市间的功能联系,构筑区域网络一体化支撑体系,构建“多中心层域式、网络状一体化”的长江三角洲全球城市区;并提出面向全球化和基于地方化的区域功能组织结构,打造若干全球化战略区以推进长江三角洲全球城市区建设。     

创新驱动我国省域绿色增长的空间效应

利用全局主成分分析法测度中国大陆地区30个省市自治区(不含西藏)2003～2016年的绿色增长水平,并构建空间面板杜宾模型,实证考察了知识创新、技术创新、制度创新、文化创新驱动省际绿色增长的空间效应.结果表明,知识创新对绿色增长水平产生显著的正向空间影响,直接效应为2.35×10-5,间接效应为3.75×10-5;本地...     

大型公共场所多源疏散的控制流模型研究

以现有的单源最快流控制算法为基础,考虑人员在大型公共场所中的实际分布状况,遵循最大限度利用各出口的原则,提出针对多源疏散的全局最优化算法。根据此算法可以得出各疏散源点经过各出口的疏散人员数量以及人员的行走路径、从源点出发和完成疏散的时刻。将算法应用于某百货公司的案例研究表明,在多源疏散的情况下,各源点依次按照单源最快流控制算法进行独立疏散,能够保证每个源点的最优疏散,但整体的疏散效率并非最优;而应用全局最优化算法进行疏散,可以充分利用疏散过程中不同出口的疏散时间差,取得减少整体疏散时间、提高疏散效率的效果。     

Atmospheric Change and the Diversity of Aquatic Invertebrates: Are We Missing the Boat?

The response of natural systems to atmospheric change may depend critically on species diversity and on the genetic diversity (variability) found within their respective populations. Yet, most surveys of aquatic invertebrates account for neither. This may be of particular concern for benthic populations in running waters because of the considerable variability and the fragmentary nature of these habitats (e.g. isolated watersheds). In such habitats, species with limited genetic variability and/or limited dispersal capabilities (genetically differentiated populations) may be unable to track rapid environmental change, and may be more susceptible to climatic perturbations. We present a conceptual framework to illustrate some of the potential problems of ignoring population genetics when considering the impacts of global atmospheric change. We then review a simple method to assess population genetic structure and we evaluate available data on the genetic structure of North American stream invertebrates. These data indicate that benthic taxa often consist of genetically differentiated local populations, or even previously unknown species. Accordingly, our limited knowledge of population structure among benthic invertebrates may result in the unwitting loss of genetic and/or species diversity. Enhanced taxonomic research incorporating molecular techniques is clearly warranted. Conservation strategies based on the preservation and remediation of a diversity of aquatic habitats are likely to be our best means of ensuring species and genetic diversity of invertebrate taxa.     

Optimisation of reduction of global CO2 emission based on a simple model of the carbon cycle

A simple model has been designed to describe the interaction of climate and biosphere. Carbon dioxide, understood as a major emitted gas, leads to a change of global climate. Economic interpretation of the model is based on the maximisation of the global CO₂ cumulative emissions. The two most important profiles of emission have been obtained: optimal and multi-exponential suboptimal profiles, each displaying different characteristics. This revised version was published online in July 2006 with corrections to the Cover Date.     

Regional analysis of global change impacts: Concepts, tools and first results

The paper introduces an approach for the analysis of global change impacts on river basins or regions. This approach is quite general and can be transferred to any region or river basin of interest on earth. The first application of the approach was in the Elbe river basin, with primary focus on the hydrologic model part and on the integration of crop growth and nitrogen dynamics. Finally, concepts for the integration of socio-economic aspects in the analysis are introduced.