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911.
城市生态补偿能力衡量和应用   总被引:77,自引:1,他引:76  
城市生态补偿在城乡开发、城市规划等许多工作中具有重要的意义。为衡量城市生态补偿能力,本文提出了绿当量的概念,并以济南市为例,探讨了对二氧化碳、降尘和二氧化硫的生态补偿方法。根据实际情况,以街道办事处为单元评价济南市内现有绿地的生态补偿能力,并根据环境目标的要求,提出了各办事处需增加的公共绿地面积,为制定市区公共绿地配置规划提供了依据。计算结果表明,从总体上说,济南市现有的绿色植物可补偿济南市排放到大气中的二氧化碳的22.3%,二氧化硫的23.1%;其总吸尘能力略大于年排尘能力。绿当量概念和计算方法在济南市城区公共绿地配置规划中的成功应用,表明它可对其它城市绿地生态补偿能力的评价和城市环境规划的制定发挥指导和借鉴作用。  相似文献   
912.
A method involving high resolution gas chromatography combined with ion trap (HRGC-MS/MS) and negative chemical ionisation (NCI) was developed for the determination of nitrated or oxygenated polycyclic aromatic hydrocarbons (nitro-PAHs, oxy-PAHs) and other electrophilic substitutes in soil samples. Efficient clean-up was achieved by a combination of methods for the determination of PAHs in soil and nitro-PAHs in aerosol using solid phase extraction (SPE) and semipreparative high performance liquid chromatography (HPLC). In samples of surface soil from the city of Basle (Switzerland), nitro-PAHs (mainly 3-nitrofluoranthene and 1-nitropyrene) were found in concentrations between 30 and 800 ng/kg dry weight. Oxy-PAHs and parent PAHs revealed 102-104-fold higher levels. Nitro-PAHs which are up to 105 times more mutagenic seem to be less persistent in soil than the parent forms, although their entire mutagenic potential has to be estimated as being on the same order of magnitude. In urban air particulate matter, the amounts of nitro-PAHs (2–62 pg/m3) were 10–100 times lower than oxyPAHs and parent PAHs which were both found in a similar range. 3-nitrobenzanthrone, a recently described suspected human carcinogen has not yet been detected. Using multivariate statistical analysis, it was possible to elucidate similarities or special characteristics of substances in a given matrix reflecting their chemical properties or specific emission sources.  相似文献   
913.
国际通用卫生填埋技术规范的实践与探索   总被引:3,自引:1,他引:2  
深圳市下坪固体废弃物填埋场按九十年代国际通用的卫生填埋技术规范和标准设计建设 ,经几年的工程建设和垃圾填埋运行管理实践中 ,在人工水平防渗结构层的设计、渗滤液处理工艺、虫害控制、填埋区清污分流及分层压实覆盖技术等方面取得了重大的研究突破 ,探索出适合我国国情的现代化卫生填埋技术规范和运作管理模式 ,建成了我国第 1座城市生态填埋场。  相似文献   
914.
A study of the area, including Rosetta city and the estuary of the river Nile (Rosetta branch), has been carried out for assessment of the impact of sea level rise (slr). A geographic information system (GIS) has been built including layers of land use, topography, archeological sites, land cover and population. Analysis of data has been carried out to assess vulnerability of various land use and land cover classes to the impact of sea level rise.Because the area under study has geomorphic relief profiles just over the sea level, inundation of total land could reach 26% of total study area due to only half a meter rise in sea level. This lost area includes 32% of urban clusters mainly used for human shelter and contains 52% of present monuments, 25% of valuable high quality dense palm trees cultivation, 75% of beaches and 19% of lands suitable, 25% of valuable high quality dense palm trees cultivation, 75% of beaches and 19% of lands suitable for agricultural reclamation (although suffering from salt water intrusion and soil salinization). This is expected to cause a significant impact on the present population, economic activities, total regional revenue, and also on tourism. At 1.1 m sea level rise, 72% to total study area could be inundated. This area contains all beaches, half of the palm cultivation, 43% of total urban clusters, which includes 81% of the monumental sites and historic buildings.Other environmental problems such as solid waste management, sanitary disposal network, deteriorating conditions of some monumental structures, in addition to the sea level rise act negatively on the environmental quality of the urban community. Future plans for urban expansion in the area must be studied carefully in order to preserve valuable palm lands and maintain and protect monuments and historic sites which help the promotion of tourism. An environmental management program is essential for upgrading tourism, promoting urban development and protecting coastal lands.  相似文献   
915.
为深入分析城市景区夜游密集人群易发生踩踏事件的脆弱性成因问题,运用人—环境耦合系统全面分析人群脆弱性模型三因子:暴露性、敏感性和适应性.依据现行标准规范与调查问卷筛选脆弱性指标,在博弈思想组合主客观权重的基础上,构建组合赋权-云模型的脆弱性综合评价模型.以大雁塔休闲旅游景区为实例,运用云算法得到各层指标的评价云图,与标...  相似文献   
916.
Two-week average NO2 concentrations were measured in Amsterdam (NL), Huddersfield (UK) and Prague (CZ) at 80 sites in each study area, to assess small area spatial variation, using a tube type and a badge type passive sampler. The badges appeared to be less robust than the tubes. The lower detection limit for tubes and badges was 3.7 and 0.91 µg/m3, respectively for fortnightly measurements. Accuracy of the samplers was determined with reference methods (chemiluminescence). The mean ratio of the concentration measured by diffusion tube over that by the reference method was 1.16, 1.03 and 0.77 in Amsterdam, Huddersfield and Prague, respectively. Standardizing the badges for the results obtained in Amsterdam, the relative mean ratio of the concentration measured by the badges over that by the reference method was 0.95 and 0.58 in Huddersfield and Prague, respectively. NO2 concentrations measured by the two designs did not differ significantly. Mean NO2 concentrations were 36, 26 and 22 µg/m3 in Amsterdam, Huddersfield and Prague, respectively. The precision of duplicate tubes and badges was 8% and 11%, respectively. Both samplers are suitable for determining real variation in small area NO2 concentrations in the ranges which occurred. It is concluded that low-cost, simple NO2 passive samplers can provide reliable information about variation in NO2 concentrations within urban or rural areas on a small spatial scale. Based on its robustness and its precision, tubes were preferred over badges.  相似文献   
917.
为了遏制长沙市城市的无序扩张,促进土地节约集约、高效利用,保障生态空间质量,划定长沙市城市开发边界成为重要举措。基于居民活动空间扩展,选取人口密度、居民活动分布、基础设施布局等多源时空数据,通过量化居民活动空间扩展概率,并利用植被覆盖度构建生态约束强度,确定二者协调规则,作为CA模型的约束条件,进行城市建设用地模拟,划定城市开发边界。结果表明:划定的长沙市城市开发边界,结果与长沙市“十三五”规划的城市空间发展框架基本一致,对未来建设用地扩展方向预测合理,而且避免了侵占重要生态资源,达到了兼顾城市空间发展和生态资源保护的多重目的。  相似文献   
918.
为分析多因素耦合作用对城市燃气管道失效可能性的影响,构建了基于复杂网络的N-K模型;应用轨迹交叉理论分析管道失效可能性因素的耦合作用机理;基于N-K模型对2011—2014年所发生的1 127起城市燃气管道事故进行耦合分析,计算不同耦合方式发生的概率和耦合值。结果表明:多因素耦合过程中,参与耦合的因素越多,管道失效的概率越大,但耦合发生的频率却随耦合因素的增加逐渐减少;环境因素和人为因素参与耦合时,管道失效的概率较大。  相似文献   
919.
长株潭城市群是湖南省的核心增长极,是"资源节约型社会、环境友好型社会"社会建设综合配套改革试验区,但伴随高速的工业化发展和城市化进程,长株潭面临着严峻的资源约束和环境压力。文章从土地利用格局、经济社会发展、环境质量状况、主要污染物排放和资源能源利用等方面入手,综合分析了长株潭城市群的环境压力,主要体现在长株潭城市群城市化与土地需求的矛盾凸显,"摊大饼"的扩张模式带来生态风险;重工业和污染排放集聚,累积性污染突出;环境空气质量和地表水环境质量形势不容乐观;资源能源利用方式粗放等。结合城市群区域规划,提出了长株潭城市群在新型城镇化建设中应采取的生态环境保护措施建议。  相似文献   
920.
Fire regimes are needed for healthy forest ecosystems, but citizens who live parallel to public forests do not always understand or favour the mechanisms land managers use for fire prevention and preparation. One way that land managers and citizens may share concerns and overcome barriers is through effective communication, allowing both parties to adequately prepare for a wildfire event. While collaboration between land managers and citizens has been well studied, the research on communication between citizens and among land managers is less prevalent yet equally important. The lack of research on communication between these parties creates an incomplete picture of the spectrum of communication that takes place in preparation for a wildland fire event. This paper reviews the current literature on communication between and among citizens and land managers before a wildfire event.  相似文献   
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