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581.
Bulk deposition samples were collected in remote, rural village and urban areas of Beijing-Tianjin region, North China in spring, summer, fall and winter from 2007 to 2008. The annually averaged PAHs concentration and deposition flux were 11.81 ± 4.61 μg/g and 5.2 ± 3.89 μg/m2/day respectively. PHE and FLA had the highest deposition flux, accounting for 35.3% and 20.7% of total deposition flux, respectively. More exposure risk from deposition existed in the fall for the local inhabitants. In addition, the PAHs deposition flux in rural villages (3.91 μg/m2/day) and urban areas (8.28 μg/m2/day) was 3.8 and 9.1 times higher than in background area (0.82 μg/m2/day), respectively. This spatial variation of deposition fluxes of PAHs was related to the PAHs emission sources, local population density and air concentration of PAHs, and the PAHs emission sources alone can explain 36%, 49%, 21% and 30% of the spatial variation in spring, summer, fall and winter, respectively.  相似文献   
582.
浠ュ箍瑗垮钩鏋滃幙榫欎綍鐢熸€侀噸寤虹ず鑼冨尯鐨勭煶婕犲寲灞卞湴澶嶅悎鐢熸€佺郴缁熶负渚?渚濇嵁璇曢獙鐮旂┒鍙婁笓瀹跺挩璇㈢殑缁撴灉,鏋勫缓浜嗕竴涓熀浜庤嚜鐒跺瓙绯荤粺銆佺ぞ浼氬瓙绯荤粺銆佺粡娴庡瓙绯荤粺鐨勮瘎浠锋寚鏍囦綋绯?閲囩敤灞傛鍒嗘瀽娉曞鎸囨爣浣撶郴涓悇鎸囨爣鐨勬潈閲嶅€艰繘琛屼簡鍒嗘瀽,搴旂敤鎸囨暟璇勪环妯″瀷瀵圭煶婕犲寲灞卞湴澶嶅悎鐢熸€佺郴缁熻繘琛岀患鍚堣瘎浼?灞傛鍒嗘瀽缁撴灉琛ㄦ槑,妞嶈瑕嗙洊鐜囥€佷汉绫绘椿鍔ㄥ己搴︺€佺墿绉嶅鏍锋€с€佺墿璐ㄧ敓娲绘寚鏁般€佺煶婕犲寲绋嬪害銆佹按鍦熸祦澶辩▼搴︾瓑鎸囨爣鐨勬潈閲嶅€艰緝澶?鏄煶婕犲寲灞卞湴澶嶅悎鐢熸€佺郴缁熺殑閲嶈褰卞搷鍥犲瓙;鎸囨暟璇勪环妯″瀷鐨勮瘎浠风粨鏋滆〃鏄?鐭虫紶鍖栧北鍦板鍚堢敓鎬佺郴缁熺殑鎬讳綋璐ㄩ噺杈冨樊,浣嗛€氳繃鐢熸€佺ず鑼冨尯寤鸿,鏀瑰杽澶嶅悎鐢熸€佺郴缁熶腑鐨勬琚姸鍐?鏀瑰杽鍐滀笟鐢熶骇鏉′欢鍜屾帹骞垮厛杩涘啘涓氭妧鏈?鎻愰珮绯荤粺涓汉绫荤殑鐢熸椿姘村钩,鍙互浣垮鍚堢敓鎬佺郴缁熶腑绀句細銆佺粡娴庛€佺幆澧?涓瓙绯荤粺鐨勮浆杩愬姛鑳介€愭笎瓒嬩簬鍗忚皟,鎬讳綋璐ㄩ噺閫愭笎濂借浆.  相似文献   
583.
Ever since the concept of metabolism was extended from biological science by social scientists to analyze human systems, socio-economic metabolism has been extensively applied to explore resource consumption, asset accumulation, waste emissions, and complex processes of land use change in a socio-economic system. Current research in socio-economic metabolism and land use change has used accounting approaches for macroscopic comparisons of countries and regions. However, socio-economic metabolism has seldom been applied to the analysis of land use change. To simulate the spatial-temporal dynamics of socio-economic metabolism and land use change, this study adopts a spatial system modeling method to develop a Socio-Economic Metabolism and Land Use Change (SEMLUC) model for the Taipei Metropolitan Region. The simulation results illustrate that the Taipei Metropolitan Region is highly dependent on inflows of non-renewable energy and exhibits a spatial hierarchy of non-renewable energy consumption centering on Taipei's Main station. Additionally, urban assets provide feedback to natural and agricultural systems to extract additional resource inflows which, driven by the maximum power principle, accelerate the convergence of energy flows toward urban assets. Accumulating urban assets also facilitates inflows of non-renewable material to nearby cells thereby enhancing land use conversion to urban areas. This work also demonstrates the capability of ArcGIS software in simulating socio-economic metabolism and land use change in an urban system.  相似文献   
584.
根据长江口洋山海域表层沉积物监测资料,利用变异系数法和富积系数法,对表层沉积物中重金属的空间波动程度及富积程度进行了分析,并采用Hakanson潜在生态危害指数法对其潜在生态危害程度进行了评价。结果表明:在表层沉积物所监测的重金属中,Pb元素的空间波动程度最高,其它重金属元素的空间波动程度较低,各重金属空间波动程度的顺序依次为Pb>Cd>Hg>Cu>Cr>As>Zn;沉积物中Cu元素的富积程度最高,Pb元素次之,其它重金属元素的富积程度较低,各重金属富积程度的顺序依次为Cu>Pb>Zn>As>Cr>Cd>Hg。潜在生态危害评价结果显示:洋山海域表层沉积物中的重金属对海洋生态系统的潜在生态危害较轻微,均属于轻微潜在生态危害程度,其轻微潜在生态危害程度顺序为Cu>As>Hg>Pb>Cd>Cr>Zn。  相似文献   
585.
The Venetian plain is a densely populated area and one of the most economically competitive regions in Europe. Therefore, a sustainable management of the water resources has to be accomplished to preserve both the social and economic value of this area and the regional environment in accordance with the European water policy directives. This paper presents the analysis of hydrologic and hydrogeological water balances of the high alluvial plain (approximately 790 km2) highlighting some important peculiarities that could be crucial for the local water policy. By focusing on the importance of different water budget components, the obtained results indicate in the irrigation the most relevant component of the aquifer recharge. Thus, the irrigation management policy of the Land Reclamation Consortia strongly influences aquifer recharge. Moreover, future scenarios (2071–2100) for the high Venetian plain are performed taking into account the changes of climate and irrigation policy. The inflow of the aquifer suffers a decrease ranging from 18% in the scenario influenced by climate change to 28% in the scenario affected by both the variations. In particular, the irrigation recharge shows the highest reduction due to both an increase in evaporation, owing to an increase in the surface temperature, or the irrigation methods. Therefore, the irrigation management policy adopted by the Land Reclamation Consortia is a fundamental concern. Changes from surface irrigation to spray or drip irrigation could strongly affect the aquifer recharge. The classical technique of surface irrigation is very useful in terms of aquifer recharge in comparison with drip or spray irrigation. However, it also requires a huge volume of water compared with the minimum desirable streamflow of a river and its management policy. Currently in Italy, the transition from conventional irrigation systems to water saving techniques is favored by the Land Reclamation Consortia in response to European and Italian directives. However, the possible reduction of the aquifer recharge could influence the actual social and economic condition of the Venetian plain because the human and industrial water needs are mostly dependent by groundwater exploitation. Therefore, water saving activities should be accompanied by appropriate corrective actions to reduce the environmental and social impact due to the decrease in aquifer recharge.  相似文献   
586.
三峡大坝附近地区有发展反季节蔬菜生产的小气候环境,有比较丰富的可开垦利用的土地资源,具有广阔的市场。秭归县因地制宜地建设“河谷平坝保护地蔬菜基地”:和“高山反季节蔬菜基地”两大类型反季节蔬菜生产基地,极大地丰富了三峡工程建设区的副食品供应,增加了库区移民的经济收入,取得了很好的经济效益,很大的社会影响和良好的生态效应。  相似文献   
587.
2013年4月~2014年1月在天津滨海新区泰达学院分季节采集23对大气样品(气相+颗粒相).分析了样品中84种多氯联苯(PCBs)异构体,结果表明,总浓度为71.08~567.36pg/m3(均值307.18pg/m3);春、夏、秋、冬四个季节的PCBs浓度分别为275.19,372.55,259.96,281.81pg/m3,季节规律不明显,冬季浓度偏高,可能是由工业源排放的PCBs和冬季较高的大气颗粒物浓度造成;气相多氯联苯占总浓度的77.47%,且季节差异明显,夏季(92.44%)>秋季(85.16%)>春季(80.61%)>冬季(42.70%);Clausius-Clapeyron (C.C)方程斜率为-5302,表明气相PCBs对温度依赖程度很大,其受到了当地工业源的影响;log KP与log PL0和log KOA的斜率分别为-0.43和0.46,偏离了气粒分配平衡时对应的斜率-1和+1,表明滨海新区大气中多氯联苯受到了当地污染源排放的强烈影响,所以没有达到平衡状态.  相似文献   
588.
天津市各区县PM2.5污染工业行业贡献构成分析   总被引:1,自引:0,他引:1  
应用MM5/CMAQ模型,选取1月和7月作为冬、夏两季的典型代表月份,采用源开关法,将天津市工业源分为8大类,模拟分析不同季节下,各类源对天津市各区县的PM2.5污染贡献.结果表明,热力供应是各区县冬季PM2.5污染的首要贡献源,贡献比例约为50%以上,而石油加工和化工制造是夏季各区县PM2.5污染贡献的一个重要来源,贡献比例从冬季的7%上升到夏季的23%;在冬夏两季,黑色金属冶炼和水泥制造是构成天津市PM2.5污染的重要来源,合计分别约占工业污染贡献比重的30%和65%;此外,除蓟县外,电力生产在冬夏两季均不是各区县PM2.5的主要贡献来源.从具体区县看,水泥制造对河北、北辰、红桥等区县有较大影响,化工制造对宁河及滨海新区有较大影响,电力生产则对蓟县有较大影响.  相似文献   
589.
天津PM10和NO2输送路径及潜在源区研究   总被引:2,自引:0,他引:2  
王郭臣  王珏  信玉洁  陈莉 《中国环境科学》2014,34(12):3009-3016
利用HYSPLIT模型和全球资料同化系统(GDAS)气象数据,用聚类方法对2012年12月~2013年11月期间抵达天津的逐日72h气流后向轨迹按不同的季节进行归类.并利用相应的PM10和NO2浓度日监测数据,分析了不同季节气流轨迹对天津污染物浓度的影响.运用潜在源贡献(PSCF)因子分析法和浓度权重轨迹(CWT)分析法分别模拟了不同季节PM10和NO2潜在PSCF和CWT.结果表明,不同方向气流轨迹对天津PM10和NO2潜在源区分布的影响存在显著差异.天津PM10和NO2日均浓度最高值对应的气流轨迹均集中在冬、春和秋季等来自内陆的西北气流;夏季影响天津的气流轨迹主要来自西北和东南方向,对天津PM10和NO2的日均浓度贡献较小.天津PM10和NO2的PSCF与CWT分布特征类似,最高值主要集中在天津本地以及邻近的河北省和山东省,是天津这两种污染物主要潜在源区.  相似文献   
590.
天津市开展初始碳核查旨在通过碳排放交易市场来控制当地的二氧化碳排放量,促进当地绿色低碳发展。以天津市燃煤型热电企业为初始碳核查对象,结合实际核查过程中遇到的"指南外"情况,探索一套适合于此类企业的碳核查方法,来准确核算其真实碳排放数据,为天津市碳排放交易市场及企业碳排放权配额分配的顺利开展奠定基础。  相似文献   
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