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1.
城市道路典型绿带结构对总悬浮颗粒物的净化效应   总被引:1,自引:0,他引:1  
机动车道和非机动车道之间的隔离绿化带(简称机非隔离绿化带)对由机动车辆造成的空气总悬浮颗粒物(TSP)有较显著的净化效应。以典型结构类型的机非隔离绿化带为研究对象,通过布点采样测定空气中TSP浓度,定量地研究了道路绿化带对TSP的净化效益。同时,用郁闭度和疏透度表征了道路绿化带的配置情况,并研究其与TSP净化效率的相关性;采用灰色关联分析方法,初步探讨了TSP净化效率与温度、相对湿度、风速的相关性。结果表明:主干道机非隔离绿化带的最优结构是乔灌结构、次干道最优结构是乔灌草结构、支路3种结构类型的道路绿化带对TSP净化效率差异不明显;绿化带疏透度在10%~20%时,郁闭度在75%~90%,绿化带对TSP净化效率较高;相对湿度对TSP净化效率的影响较风速和温度大  相似文献   

2.
Material prepared for Connecticut's 1979 State Implementation Plan (SIP) submittal indicates that transportation related sources contribute more than half of total suspended particulates (TSP) emissions. The SIP's conclusions are strikingly different from earlier estimates of TSP attributable to the transportation sector. The conclusions mandate additional measurements and analyses to document source contributions. Of greater importance is the development of TSP control measures because Connecticut's ability to maintain an adequate transportation system and to accommodate stationary source, commercial and industrial growth are affected. Possible control measures must consider control of exhaust emissions, a source control program, and control of reentrained road dust having characteristics of a fugitive emissions control program. Current programs are discussed and analyzed where sufficient data exists. Technical methodology and administrative responsibilities are discussed. Insights of future program needs are presented.  相似文献   

3.
重庆市汞污染的观测研究   总被引:1,自引:0,他引:1  
为研究重庆市区汞污染状况,2004年9~11月,同步观测了重庆市近郊铁山坪小流域(TSP)和观音桥(GYQ)两个区域的全沉降、穿透水、地表径流和土壤中的总汞含量,估算了小流域中汞的输入输出通量,分析了城区和郊区的大气汞沉降和分布特征。结果表明,重庆已在一定程度上受到汞污染。在TSP,湿沉降是汞输入的主要方式,也就是说,在TSP,细颗粒是大气汞的主要来源,表层土则是大气汞的一个主要的汇。GYQ区域的汞污染比TSP相对严重。在GYQ,除了湿沉降以外,干沉降是汞来源的重要形式,表明在GYQ,粗颗粒可能对大气汞有很大的贡献。因此,本地源的排放对城区的影响比对郊区的影响大,尤其是城区火电站附近的土壤样品比郊区土壤的汞含量高很多,说明火电站是大气汞的重要来源之一。  相似文献   

4.
Estimates of source contribution are important for setting more realistic air quality standards for total suspended particles (TSP). Soil dust contributes a major fraction of the atmospheric particulate load in India during the dry months. Chemical element balance (CEB) analysis shows that nearly 50% to 60% of the TSP in Bombay during winter months are of crustal origin. Wind-raised dust from parched earth surface and traffic dust from badly maintained roads are the probable causes of the observed higher contribution of soil dust.  相似文献   

5.
Samples of atmospheric particulate matter obtained from representative areas of the city of Baghdad were collected on glass fiber filters using a high-volume sampler. Atomic absorption techniques were used to analyze the total suspended particulates (TSP) for the following trace metals; Fe, Cu, Zn, Pb, Mn, Cr, Cd, Co, and Hg. Sulfates were measured by turbidemetric method. Ion-selective electrodes was used for chloride analysis. It is concluded that the major components of TSP in the ambient air of Baghdad consist of mineral dust. Pb and Cd gave high enrichment factor values, which implies enrichment of these two metals from anthropogenic sources. High enrichment factors were also obtained for Zn and Cu. It is also concluded that in this arid area, the black smoke reflectance method is not suitable for measuring total suspended matter gravimetrically.  相似文献   

6.
城市影响区格局分析的定量方法——以江西省为例   总被引:2,自引:0,他引:2  
城市及其影响范围划分方法的研究一直是学界的热点,要实现方法上的简易性和结果上的精确性难度较大,Arcgis强大的空间分析功能成功解决了这一难题。在Arcgis和1〖DK1〗∶250000 基础地理数据、江西省1997和2007年交通路网数据的支持下,分别应用最短时间距离和场强模型对江西省城市时间影响范围和腹地影响范围进行了划分。结果表明:最短时间距离针对同等级城市影响范围划分具有合理性,考虑城市质量的场强模型则适合于对不同等级城市的腹地影响范围划分;江西省交通条件总体得到改善;交通对城市腹地范围演变作用显著;交通建设的边际效用明显,改善交通落后地区的路网比改善交通相对发达地区的路网获益更大,也更有利于实现区际公平;部分城市行政区划极不规则,与城市腹地范围相差悬殊,省管县模式将有助于此问题的解决。  相似文献   

7.
基于TM遥感影像、城市规划图等数据,利用logistic CA模型,模拟了2005~2010年天津市滨海新区城市形态演化,经过模拟面积和Lee Sallle指数两个指标的精度评价后,定量分析了新版总规实施后城市形态演化的驱动力。实证研究表明:滨海新区城市形态扩展迅速,驱动力大小依次是自然环境、经济发展、交通带动、城市规划引导;其中交通驱动力中,影响最强烈的依次是火车站、城市的道路、高速出入口、县乡道、航道、省道。因此提出:城市规划必须顺应城市形态发展的规律,把握好可控的关键驱动力,科学预测城市形态发展和提出城市规划方案,做到积极有效的引导城市形态发展  相似文献   

8.
Particulate air pollution in Lanzhou China   总被引:4,自引:0,他引:4  
Chu PC  Chen Y  Lu S  Li Z  Lu Y 《Environment international》2008,34(5):698-713
Concentrations of total suspended particles (TSP) and PM(10) in Lanzhou China have been kept high for the past two decades. Data collected during the intensive observational period from October 1999 to April 2001 show high TSP and PM(10) concentrations. Starting from November, the PM(10) pollution intensifies, and reaches mid to high alert level of air pollution, continues until April next year, and is at low alert level in the summer. In the winter and spring, the TSP concentration is 2-10 times higher than the third-level criterion of air quality (severe pollution). Effects of intrinsic factors (sources of pollution) and remote preconditions (propagation of dust storms) for severe PM(10) and TSP pollution in Lanzhou are analyzed.  相似文献   

9.
基于1995~2010武汉城市圈城乡路网空间数据,综合运用复杂网络理论、动力系统理论及现代控制理论等多学科的方法和理论,采取随机故障和蓄意侵略两种攻击策略及多种评价指标,通过建立动力学演化模型并进行模拟仿真,揭示武汉城市圈城乡道路网的空间稳定性:(1)因分布相对均匀,节点连接随机多样,在面临随机攻击时,武汉城市圈城乡路网体现出“类随机性”,抗攻击能力强;(2)高度节点、高介数节点失效时,引致的城乡路网效率和结构变化程度不一,高介数节点失效往往更容易导致路网破碎和效率降低(形成众多子图);(3)桥梁和高速成为整个圈域城乡路网的关键边,不同桥梁或高速路段相对网络稳定性的重要程度不一样:圈域中心城区的大桥和二桥、南北向的京港澳、大广高速成为整个城乡路网的关键路径  相似文献   

10.
Tehran metropolitan region (TMR) has experienced rapid urbanization in the last few decades. This accelerating urbanization trend mainly arising from high natural population growth and rural–urban migration along with rapid socioeconomic changes formed unplanned and uncontrolled urban expansion in peri-urban areas and resulted in degrading environmental quality and considerable changes in the urban landscapes of the TMR. Thus, the main objective of this research is to model spatial pattern of urban growth in eastern corridor of TMR using GIS-based SLEUTH model and the prediction of future developments of the region from 2014 to 2060. The SLEUTH is one of the most powerful models for urban growth modeling. This model analyzes the spatial pattern of urban growth based on historical data obtained from satellite images of 1987, 2003, 2011, and 2014. The results indicate that the most important factors affecting the urban growth are slope resistance and road gravity. The slope resistance is the highest coefficients value, which illustrates the limiting influence of the slopes on general trend of urban growth in eastern corridor of the TMR. The road gravity stands in second place where it displaces orientation of linear form of outlying pattern alongside the transportation network; it represents that the main pattern of urban growth in peri-urban areas of the region have a linear nature and edge expansion due to slope resistance and road-influenced growth, while spread, diffusion, and breed coefficients display low probability of new spreading center and spontaneous growth in the study area. In addition, the prediction of urban growth for 2020–2060 revealed that urban expansion which was 41,500 ha in 2014 will increase to 179,400 ha in 2060 with noticeable growth rate of 145.6 %. Comparing study area and other researches indicate that the urban growth happens in high rate in eastern corridor. One of the main reasons of this growth goes back to the formation of the second homes for residents of Tehran metropolitan city.  相似文献   

11.
城市的扩张与道路交通的发展是相辅相成的。道路建设造成了城市景观的破碎化,使城市景观呈现不同的空间格局和空间异质性特征,并且这种空间异质性随着时间的变化而发生改变。在RS和GIS技术的支持下,利用1989、1999和2008年的Landsat TM/ETM+数据,以南京市为例对道路交通网络与城市土地利用之间关系进行了不同层次和尺度的空间分析。结果表明:1989~2008年近20 a来,南京市城市空间形态扩展迅速,建设用地面积从1989年的1003 km2增加到2008年的6847 km2;在不同时期,南京市城市化过程表现出不同的道路交通网络结构和城市空间扩展模式;由道路交通建设造成的局部区域的景观破碎度在一定程度上能够反映周边区域的土地利用强度;土地利用强度和由道路交通建设造成的景观破碎度均表现出显著的空间自相关性,随时间推移,这种特征愈加明显,并且二者在表征城市空间拓展方面具有较高的耦合度;受其他辐射中心的作用,交通干线周边地区土地利用强度并未表现出距离指数衰减效应  相似文献   

12.
以浙江省69个县域行政单元为研究对象,根据城乡关联内涵及特点,构建综合评价指标体系,运用主成分分析法和探索性空间数据分析方法,定量测度浙江省2001~2011年县域城乡关联性,并分析城乡关联时空演变特征及空间关联状态。研究表明:(1)各县域城乡关联综合得分均出现不同程度的增长,表明区域城乡经济社会统筹得到优化;(2)城乡关联空间存在差异,东部沿海平原县域城乡关联性普遍高于西部低山丘陵县域,地级市辖区城乡关联性明显高于各县(县级市);(3)城乡关联表现出较强的空间集聚特性,城乡关联较强的县域主要分布于长三角环杭州湾地区,城乡关联较弱的县域则集中分布于浙西南低山丘陵区域。在此基础上,提出经济水平发展、交通设施改善、要素联系强化、政策制度优化等4因素为浙江省城乡关联演变的主要动力机制  相似文献   

13.
Measurements and analysis of criteria pollutants in New Delhi, India   总被引:2,自引:0,他引:2  
Ambient concentrations of carbon monoxide (CO), nitrogen oxides (NOx), sulfur dioxide (SO2), and total suspended particulates (TSP) were measured from January 1997 to November 1998 in the center of downtown [the Income Tax Office (ITO) located on B.S.G. Marg] New Delhi, India. The data consist of 24-h averages of SO2, NOx, and TSP as well as 8 and 24-h averages of CO. The measurements were made in an effort to characterize air pollution in the urban environment of New Delhi and assist in the development of an air quality index. The yearly average CO, NOx, SO2, and TSP concentrations for 1997 and 1998 were found to be 4810+/-2287 and 5772+/-2116 microg/m3, 83+/-35 and 64+/-22 microg/m3, 20+/-8 and 23+/-7 microg/m3, and 409+/-110 and 365+/-100 microg/m3, respectively. In general, the maximum CO, SO2, NOx, and TSP values occurred during the winter with minimum values occurring during the summer, which can be attributed to a combination of meteorological conditions and photochemical activity in the region. The ratio of CO/NOx (approximately 50) indicates that mobile sources are the predominant contributors for these two compounds in the urban air pollution problem in New Delhi. The ratio of SO2/NOx (approximately 0.6) indicates that point sources are contributing to SO2 pollution in the city. The averaged background CO concentrations in New Delhi were also calculated (approximately 1939 microg/m3) which exceed those for Eastern USA (approximately 500 microg/m3). Further, all measured concentrations exceeded the US National Ambient Air Quality Standards (NAAQS) except for SO2. TSP was identified as exceeding the standard on the most frequent basis.  相似文献   

14.
Polychlorinated biphenyls (PCBs) bound to total suspended particles (TSP) were determined in the area of Eordea basin, NW Greece, where intensive coal burning for electricity production takes place. The concentrations of PCBs exhibited high variability although within the range reported for urban industrialized areas. The presence of PCBs in fly ash generated from coal burning as well as in particulate emissions from vehicles, domestic heating, burning of refuses and biomass was also examined. The particles emitted from vehicles and central heating exhibited the higher content of PCBs, whereas fly ash the lower. The pattern of PCBs in TSP as well as in particulate emissions was discussed.  相似文献   

15.
交通道路对区域土地利用变化的影响研究进展   总被引:1,自引:0,他引:1  
交通运输业是国民经济的重要组成部分,但科学评价交通道路对区域土地利用变化的影响尚未受到足够重视。为此,通过搜集大量文献,归纳了高速公路、普通公路、城市轨道交通、铁路等交通道路对区域土地利用变化的影响。研究表明,目前的研究方向主要集中在交通道路对于区域土地利用类型和景观格局的影响上。研究发现,交通道路可以通过改变交通可达性,影响周边区域土地利用变化,其影响程度与道路等级、与道路距离、原有土地利用类型等有着密切关系。相比较于开放型道路,封闭型交通道路如高速公路、城市轨道交通、铁路等,其对于周边区域土地利用变化的影响主要通过出入口、站点等实现,并在“点”状影响的基础上形成“轴”状影响;在研究方法上,国外学者侧重模型分析,国内学者侧重宏观分析,缓冲区分析等方法是目前普遍使用的方法,但在严谨性上有待改进。最后在特殊节点、特殊地域、改进方法、建立模型等方面对未来的研究进行了展望。 关键词: 交通;土地利用;变化;影响  相似文献   

16.
Hourly concentrations of TSP, PM(10), PM(2.5) near the surface at Seoul city were examined from March 20 to March 25, 2001 (duststorm event) in order to investigate the effect of a duststorm generated in China on the local aerosol concentration in Korea, The ratios of fine to coarse particles such as TSP to PM(10), TSP to PM(2.5) and PM(10)-PM(2.5) to PM(2.5) showed that a great amount of dust transported from the origin of the duststorm was remarkable with a maximum ratio of 9.77 between TSP and PM(2.5). Back trajectories every 6 h showed the movement of dust particles in the lower atmosphere near 500 m to 1500 m (atmospheric boundary layer), which implied transport from Baotou in inner Mongolia of northern China to the direction of Seoul city in Korea and then the back trajectories passed near the southern border of Mongolia and Baotou through Zengzhou in the midlevels (3000 m) and low levels (500 m) of China, finally reaching Seoul city. So, the TSP concentration at Seoul city was partially influenced by the duststorm, under the prevailing westerly wind and the transported aerosols could influence high concentrations of pollutants of TSP, PM(10) and PM(2.5) in Seoul. The sudden high concentrations of TSP and PM(10) were found for a few hours, especially at 1500 to 1800 LST, March 22. At 1200 LST, before the passage of a cold front through the Korean peninsula, the convective boundary layer (CBL) near Seoul was not shallow, but at 1500 LST, under the frontal passage, the CBL was remarkably thinner (less than 300 m), due to the compression of the boundary layer by the intrusion of cold air. This resulted in the increase of the TSP concentration, even though the mixed layer above maintained almost the same depth. At 1800 LST shortly after the frontal passage, that is, near sunset, the nocturnal cooling of the ground caused air parcels to cool, thereby enhancing the shallower nocturnal surface inversion layer and producing the maximum concentration of TSP of 1388 microg/m(3) near Seoul city.  相似文献   

17.
我国正处于公路交通飞速发展的历史阶段,公路建设在促进社会经济发展的同时也带来了显著的生态环境问题。由于目前建设项目环境影响评价的局限性日益突出,环评法以及相继出台的部门规章都要求从战略层次科学评估交通规划造成的潜在环境影响,促使交通战略的决策过程充分考虑环境因素。然而,我国交通战略环境评价起步较晚并较多关注于内容框架的研究,因此从宏观层面上对公路网规划的环境评价方法还有待完善和深入研究。以融合国际经验的湖北省骨架公路网规划战略环境评价为例,从规划分析、现状调查、指标体系、影响预测、制度分析和公众参与等方面,详细分析了我国公路网规划环境影响评价的技术路线确定、评价要点识别以及评价方法选取等内容,并从层次性和介入时机等方面讨论了我国交通战略环境评价存在的不足,为完善交通规划战略环境评价提供参考  相似文献   

18.
道路拥堵与城市雾霾是机动车行驶带来的两个负溢出效应,大量文献揭示了城市机动车行驶对二者带来的影响,却鲜有文献关注道路拥堵程度与雾霾污染之间的内在联系。这其中的缘由在于,一则道路拥堵程度与雾霾污染之间互为因果,同时有共同的影响因素,由此带来的内生性难题难以有效解决;其次,采用统一标准来测度不同城市道路拥堵程度的数据难以获得。为此利用高德地图(Amap)根据机动车定位导航系统提供的城市拥堵延时的大数据,来捕获各省会城市每日道路交通的拥堵程度,同时运用各城市每日的燃油销售价格、国际市场原油价格以及上一周同一工作日道路的拥堵程度作为工具变量,通过两阶段最小二乘法(2SLS)估计道路拥堵程度对城市雾霾污染的影响。回归结果表明:①以城市燃油价格作为工具变量时,道路拥堵程度每增加1%,会导致省会城市PM2.5、PM10分别增加6.5%和6.7%;②以国际原油价格、上一周同一个工作日拥堵程度作为工具变量,以及改用GMM方法进行估计时,基准回归的结论仍然稳健,城市的治堵举措与治霾举措能够相互协同;③进一步以省会城市新增轨道交通来实现治堵和治霾的例子表明,发展轨道交通来实现治堵与治霾的协同效应,要以有效治堵作为前提,否则减排治霾的协同效果无法实现。  相似文献   

19.
中国城市化进程中的城市道路交通碳排放研究   总被引:7,自引:0,他引:7  
探讨了中国城市化、经济发展、技术进步等与城市道路交通碳排放之间的长期均衡关系与动态作用机制,并对中国城市道路交通碳排放进行了预测和情景分析。结果表明:①城市化率、交通能源强度、城市居民消费水平和人均GDP对城市道路交通碳排放的长期均衡弹性分别为0.93、0.73、0.68、0.44;②城市道路交通碳排放的最大贡献者在中短期内是交通能源强度,长期内是城市化率;③人均GDP增长率的提高,短期内会促使城市道路交通碳排放增长率提高,而长期又有助于使之降低;④中国城市道路交通碳排放持续增长的趋势在相当长时期内不可避免;⑤不同的发展理念和政策与技术的组合,可以使城市道路交通碳排放发生重大变化。基于研究,提出了中国城市道路交通碳减排的政策取向。  相似文献   

20.
资源短缺背景下长江三角洲城市发展研究   总被引:2,自引:0,他引:2  
资源短缺是中国城市发展中的根本性制约因素,城市发展的速度及方式应与生态环境相协调,实现对短缺资源的集约使用,文章分析了城市短缺资源的若干属性及其相应的制约化要求,并以长江三解洲为具体分析案例,探讨了资源短缺条件下城市发展的各方面抉择,对中国城市、区域发展,城乡协调具有普遍性意义。城市发展的短缺资源具有不可替代性、广需性、地区性、派生性、组合作用的复杂性等特征。在资源短缺的现实背景中,长江三解洲的城市发展速度、发展方向都应考虑与短缺资源的永续使用相匹配;城市化应在考虑地方经济、社会与资源环境的组合特征中,寻求切合实际的道路;在城市与区域空间发展形态上必须针对环境超负荷的现实,选择城镇群体空间开敞而个体空间相对紧凑的发展模式,实现城乡区域的协调发展。  相似文献   

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