城市水环境治理运作机制构建与创新

中国实行改革开放以来，工业化和城市化推动了城市经济的快速增长，但城市水环境破坏严重。政府部门曾采取一些措施来改善水环境，但并未有效解决污染问题。由于城市水环境治理问题的重要性和紧迫性，国家科技部在武汉市汉阳区启动“水专项”寻求有效的治理模式。由于采用新的制度安排，注重科学技术与管理制度的结合，明显改善了汉阳地区的水环境。“武汉水专项”的试验显示出市场机制在城市水环境治理这类公益项目中同样是有效率的。构建更加有效的城市水环境治理运作机制既是必要的，也是可能的。构建城市水环境治理运作机制的核心是在确保水环境改善的公共目标的基础上，实现城市水环境治理投入的外部效应内部化，城市水环境治理可以成为具有广阔市场和丰厚盈利的现代服务业.     

Detection and visualization of storm hydrograph changes under urbanization: an impulse response approach

Urbanization often alters catchment storm responses, with a broad range of potentially significant environmental and engineering consequences. At a practical, site-specific management level, efficient and effective assessment and control of such downstream impacts requires a technical capability to rapidly identify development-induced storm hydrograph changes. The method should also speak specifically to alteration of internal watershed dynamics, require few resources to implement, and provide results that are intuitively accessible to all watershed stakeholders. In this short paper, we propose a potential method which might satisfy these criteria. Our emphasis lies upon the integration of existing concepts to provide tools for pragmatic, relatively low-cost environmental monitoring and management. The procedure involves calibration of rainfall-runoff time-series models in each of several successive time windows, which sample varying degrees of watershed urbanization. As implemented here, only precipitation and stream discharge or stage data are required. The readily generated unit impulse response functions of these time-series models might then provide a mathematically formal, yet visually based and intuitive, representation of changes in watershed storm response. Nominally, the empirical response functions capture such changes as soon as they occur, and the assessments of storm hydrograph alteration are independent of variability in meteorological forcing. We provide a preliminary example of how the technique may be applied using a low-order linear ARX model. The technique may offer a fresh perspective on such watershed management issues, and potentially also several advantages over existing approaches. Substantial further testing is required before attempting to apply the concept as a practical environmental management technique; some possible directions for additional work are suggested.     

Diffuse pollution loading from urban stormwater runoff in Daejeon city, Korea

In this paper, stormwater runoff from an urban watershed with combined sewer systems located in Daejeon metropolitan city, Korea, was characterized to measure the stormwater runoff discharge rates and pollutant concentrations. The observed averaged event mean concentrations (EMCs) of combined sewer overflows (CSO) were 536.1mg TSS/L, 467.7 mg TCODcr/L, 142.7 mg TBOD/L, 16.5mg TN/L, and 13.5mg TP/L. A detention basin was proposed to reduce CSO, and its essential design elements were discussed. The first flush significantly affected contaminant constituents in the descending order of suspended solid>organics>nutrients. Storage volumes for containing the first flush to improve water quality of the receiving stream can be estimated based on the total suspended solid loading. In this study, detention of the first flush equivalent to 5mm of precipitation could reduce CSO-induced diffuse pollution loading to a receiving water body by up to 80% of the total suspended solid loading.     

Nonstructural Urban Stormwater Quality Measures: Building a Knowledge Base to Improve Their Use

This article summarizes a research project that investigated the use, performance, cost, and evaluation of nonstructural measures to improve urban stormwater quality. A survey of urban stormwater managers from Australia, New Zealand, and the United States revealed a widespread trend of increasing use of nonstructural measures among leading stormwater management agencies, with at least 76% of 41 types of nonstructural measures being found to be increasing in use. Data gathered from the survey, an international literature review, and a multicriteria analysis highlighted four nonstructural measures of greatest potential value: mandatory town planning controls that promote the adoption of low-impact development principles and techniques; development of strategic urban stormwater management plans for a city, shire, or catchment; stormwater management measures and programs for construction/building sites; and stormwater management activities related to municipal maintenance operations such as maintenance of the stormwater drainage network and manual litter collections. Knowledge gained on the use and performance of nonstructural measures from the survey, literature review, and three trial evaluation projects was used to develop tailored monitoring and evaluation guidelines for these types of measure. These guidelines incorporate a new evaluation framework based on seven alternative styles of evaluation that range from simply monitoring whether a nonstructural measure has been fully implemented to monitoring its impact on waterway health. This research helps to build the stormwater management industry’s knowledge base concerning nonstructural measures and provides a practical tool to address common impediments associated with monitoring and evaluating the performance and cost of these measures.     

长三角城市群高质量绿色发展的均衡性特征及障碍因素

从绿色核心动力、环境基底、创新产业、发展绩效四个维度构建评价体系,运用CRITIC赋权、核密度估计、重心—标准差椭圆等方法,从均衡态、均衡度、均衡熵角度探讨长三角城市群高质量绿色发展的均衡状况,并分析其障碍因素。结果表明：（1）高质量绿色发展存在明显的空间差异,但未出现空间极化现象;总体格局呈西北—东南向,重心位于南北居中、东西偏东的位置。（2）高质量绿色发展总体水平较为均衡,但其中创新维度均衡度较低;城市内部均衡度存在明显的省域分化,沪苏浙城市明显优于安徽省内城市。均衡熵表明多数城市系统协调度有优势,具备一定发展潜力。（3）创新水平、环境质量、土地集约、现代产业等是高质量绿色发展普遍存在的障碍因素。坚持创新驱动,建设现代产业体系,加强国土空间治理是长三角城市群高质量绿色发展的紧迫任务。     

长三角城市群水—能源—粮食系统压力的演变特征及其影响机制

城镇化的推进加剧资源消耗,水—能源—粮食（Water-Energy-Food）作为核心资源,是保障区域可持续发展的关键。以长三角城市群为例,构建WEF系统压力指数,揭示1990—2018年间长三角城市群WEF系统压力的演变特征,探讨城镇化推进对WEF系统压力的影响机制。结果显示：2010年后,随着长三角一体化进程加快,WEF系统压力明显加大,其中粮食压力猛增、水资源压力稳定、能源压力有所下降,但能源供应仍存缺口。各省市WEF系统压力及其变化特征与资源禀赋、经济发展和城镇化进程相关。城市空间扩展、人口集中、经济发展和居民消费显著影响长三角城市群WEF系统压力。因此,WEF系统管理应立足不同要素演变特征,同时加强不同部门及区域的协同管理,共同促进长三角城市群的可持续发展。     

Variations in traffic-related polycyclic aromatic hydrocarbons in PM2.5 in Kanazawa, Japan, after the implementation of a new vehicle emission regulation

A three-year sampling campaign was conducted at a roadside air pollution monitoring station in the urban area of Kanazawa, Japan. Due to a new emission regulation, PAHs levels decreased over the sampling campaign, exhibiting values of 706 ± 413 pg/m³ in 2017, 559 ± 384 pg/m³ in 2018, and 473 ± 234 pg/m³ in 2019. In each year, similar seasonal variations in PAHs levels were observed, with higher levels observed in winter and lower levels in summer. Among the PAHs isomer ratios, we observed that the ratio of benzo[b]fluoranthene (BbF) and benzo[k]fluoranthene (BkF), [BbF]/([BbF] + [BkF]), and the ratio of indeno[1,2,3-cd]pyrene (IDP) and benzo[ghi]perylene (BgPe), [IDP]/([BgPe] + [IDP]), showed stability over the sampling campaign and were less affected by the new emission regulation, seasonal variations, and regional characteristics. When using the combined ratio ranges of 0.66 - 0.80 ([BbF]/([BbF] + [BkF]) and 0.26-0.49 ([IDP]/([BgPe] + [IDP]), traffic emissions were clearly distinguished from other PAHs emission sources. Principal component analysis (PCA) and positive matrix factorization (PMF) were also performed to further analyse the characteristics of traffic-related PAHs. Overall, this study affirmed the effectiveness of the new emission regulation in the reduction of PAHs emissions and provided a combined range for identifying PAHs traffic emission sources.     

深圳市的城市化及城市洪涝灾害

城市洪涝灾害是我国自然灾害中影响最严重的灾害之一,城市化作为我国经济发展的结果,使城市洪涝灾害损失日趋严重。本文针对我国城市化发展现状及趋势,在已有城市洪涝灾害研究成果的基础上,将城市水文学的概念应用于水力学模型之中,通过对深圳市洪涝灾害的数值模拟,初步探明了城市化对洪涝灾害的影响。     

Heavy Metal Contamination and Distribution in the Urban Environment of Guangzhou, SE China

Ever-increasing heavy metal accumulation in the urban environment of Guangzhou, the largest light industrial production base and one of the most rapidly developing cities in China, poses a serious threat to environment as well as to human health in the region. As a sink or source, urban deposits are good indicators of the level and extent of heavy metal accumulation in the surface environment. The aim of this preliminary study was to examine the distribution of heavy metal contamination in the urban environment of Guangzhou. It was based on a systematic sampling of road dusts and corresponding gully sediments along major roads running mainly through commercial and residential to industrial districts of the city. In addition to road dusts and gully sediments, ceiling dusts from the Pearl River Tunnel were also collected to characterize anthropogenic emissions dominated by traffic-related activities. In general, the level of Cd, Cu, Pb and Zn contaminations were more severe on the industrialized side of Guangzhou than on the western side where heavy traffic and industrial activities were limited. The primary determinants of the level of heavy metal contamination and the distribution of this contamination in the urban environment of Guangzhou were the site-specific conditions of its urban setting, particularly the types of industries, the nature of the traffic flow, sample residence times and variations in grain size of the particulate contaminants. This study highlights the complexity of the urban system and indicates that in just such a system individual urban components should be interlinked to assess the long-term environmental and health effects of heavy metal contamination. Among the heavy metals tested – Cd, Cu, Pb and Zn – the level of Zn contamination was the most severe and widespread, and thus requires immediate attention.     

城市社区环境污染来源及对策研究

本文研究了处在城市中心的四川师范学院在可持续发展中的环境生态问题。针对废水、废气、城市生活丧圾等问题提出了防止环境恶化建设美好生态园区的措施与对策。