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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
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Collective actions of stakeholders are required for fulfilling the climate commitments of the Kyoto protocol. The insurance sector's global influence and societal impact is fairly well documented. The sector influences societies based on its interaction with stakeholders, on its products, business and political stance. As such, it is a critical actor in facilitating key climate change actions of mitigation and adaptation, and has already been recognized as a leading sector in terms of climate adaptation. The aim of this paper is to explore the role of non-life insurers in fulfilling the climate commitments of the Kyoto Protocol. This paper is based on a case study on Nordic non-life insurance companies. The study documents that Nordic insurers are responding to climate-related threats and opportunities in a strategic manner by reducing their own impacts, through their core activities, and by influencing others to act. Although Nordic insurers do not classify their actions into mitigation and adaptation, but classify them according to their core activities, they demonstrate through actions their role as potential allies for nations in fulfilling the Kyoto protocol climate commitments. The study also reveals that the commercial reality of the industry is not the same as the expected contribution to climate commitments, for instance as specified in international conventions and treaties and in the Intergovernmental Panel on Climate Change (IPCC) and industry reports. 相似文献
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PM_(2.5), formally defined as particulate matter with diameter less than 2.5 μm, is one of most harmful air pollutants threatening human health. Numerous epidemiological studies have shown that both short-term and long-term exposures to PM_(2.5) are strongly linked with respiratory diseases. In this study, various types of spatio-temporal data were collected and used to estimate the spatio-temporal variation of PM_(2.5) exposure in Beijing in 2014. The seasonal and daily variation of the population-weighted exposure level(PWEL) in 2014 was estimated and compared. The results show that the population exposure to ambient air pollution differs significantly in the four seasons, and the exposure levels in winter and spring are notably higher than the other seasons; the exposure level changes greatly from North to South, and each sub-district maintains similarity to neighboring sub-districts. 相似文献
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Is urban development an urban river killer? A case study of Yongding Diversion Channel in Beijing, China 总被引:1,自引:0,他引:1
Xi Wang Junqi Li Yingxia Li Zhenyao Shen Xuan Wang Zhifeng Yang Inchio Lou 《环境科学学报(英文版)》2014,26(6):1232-1237
The high population and concrete environment alter urban areas by changing temperature, rainfall runoff, and water resource utilization activities. This study was conducted to investigate the water quality features of the Yongding Diversion Channel in Beijing, China, and its relationship with rainfall and urban development. Monthly water quality data were obtained from April to October of 2004 at monitoring sites of Sanjiadian, Gaojing, Luodaozhuang, and Yuyuangtan. The monthly water quality grades from 2007 to 2011 were also investigated and compared with those of other rivers. Dissolved oxygen and pH showed greater decreases after one or two moderate rainfall events than several light rainfall events. The potassium permanganate index (CODMn), ammonia nitrogen (NH3-N) and total phosphorus (TP) increased more after several light rainfall events than after one or two moderate or heavy rainfall events. Pollutant concentrations (CODMn, NH3-N, TP) in downstream regions showed greater changes than those in upstream areas after heavy rainfall events. Intense human activities around the channel greatly influenced the water quality of the channel in rainy season because of runoff pollution; however, heavy rainfall had a strong dilution effect on the pollutant concentrations in rivers. Overall, urban development has obviously deteriorated the water quality of the Yongding Diversion Channel as indicated by an increase in the water quality index from 3.22 in 2008 to 4.55 in 2010. The Pearson correlation between monthly rainfall and water quality indices from 2007 to 2011 ranged from 0.1286 to 0.6968, generally becoming weaker as rainfall and rainfall runoff became more random and extreme. 相似文献
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Landscapepatternsandtheirevolutions10thesuburbanecotone──AcasestudyoftheeasternsuburbofBeijingYangJurong,ZhangHongmei,HuangYi... 相似文献
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Darja B. Žarković Žaklina N. Todorović Ljubinka V. Rajaković 《Journal of Cleaner Production》2011,19(6-7):764-774
In this study, the performance and the efficiency of physico-chemical effluent treatment in a paper mill was investigated, with the aim of evaluating the treatment rationality and running stability. The effluent treatment plant (ETP) uses alum as a coagulant and polyacrylamide as a flocculant in multi-stage water purification. Inadequate efficiency and some operational problems were observed and their occurrences were investigated. Several simple measures inside the mill and some technical measures can prevent or postpone expensive end-of-pipe treatment investments, such as biological treatment. Chemically enhanced primary treatment under optimal operating conditions can be a stand-alone technique for achieving high quality effluent. Furthermore, reductions in wastewater generation in combination with fiber and filler recovery provide environmental benefits as well as significant economic savings in production. The advantages of the cleaner production approach in existing treatment units compared to expensive biological end-of-pipe technologies are obvious. This study demonstrated that the examined mill could easily and cost-effectively change its water system toward strict discharge limits by continuing to use the existing treatment units. 相似文献
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Hettyey A Laurila A Herczeg G Jönsson KI Kovács T Merilä J 《Die Naturwissenschaften》2005,92(4):188-192
Interpopulation comparisons of variation in resource availability and in allocation patterns along altitudinal and latitudinal gradients allow insights into the mechanisms shaping the life history of animals. Patterns of between-population differences in female life history traits have been studied intensively across a wide range of taxa, but similar investigations in males have remained scarce. To study if testis weight—a measure of reproductive investment—varies on a geographical scale in anurans, we focussed on the variation in relative testis weight (RelTW) and asymmetry in 22 populations of the common frog Rana temporaria along a 1,600-km latitudinal transect across the Scandinavian peninsula. We found that RelTW decreased towards the north. Body mass and body length both had independent positive effects on testes mass. We found evidence for directional asymmetry (DA) in testis weight with the right testis being larger than the left. The level of DA in testis weight was not related to latitude, but both body mass and testes mass had independent positive effects on asymmetry. We discuss the northwards decrease in RelTW in terms of a decreased reproductive investment as a possible consequence of harsher environmental conditions, and perhaps also, weaker sexual selection in the north than in the south. 相似文献
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《环境科学学报》2012,32(4)
通过运用生态服务效能指数的概念,选择5种指标因子(吸收二氧化硫量、吸收热量、蒸腾水量、涵养水源量、滞尘降尘量)构建了淮安生态新城绿地系统生态服务效能评估模型,并运用全排列多边形图示指标法,针对“现状条件”、“概念规划”、“控制性详细规划”、“理想状态”4种情景下的绿地系统进行了生态服务效能评价与预测.结果表明,4种不同的土地利用方式下,绿地系统生态服务效能综合指数分别为0.24、0.56、0.70和0.89,生态服务效能逐步改善.研究结果进一步表明,在“概念规划”和“控制性详细规划”两种情景下,应使城市绿地系统面积大于1200hm^2,采用复合式绿地结构并调整林地与草地面积的比例达到7:3,同时应保证本地植物指数大于70%,研究结果可为生态城市建设提供一定的参考. 相似文献
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The inter-conversion of nitrogen and sulfur species between the gas and particulate phases and their interaction with alkaline species influences the acidity of the aerosols and surface snow. To better understand these processes, a short field campaign was undertaken in Ny-Ålesund, Svalbard, during 13th April 2012 to 24th April 2012. Air measurements were carried out through a particulate sampler equipped with denuders and filter packs for simultaneous collection of trace gases (HNO3, NO2, SO2 and reactive nitrogen compounds) and aerosols, with daily collection of snow samples. Ionic composition of the samples was analyzed using ion chromatography technique. The results suggested that nitrate-rich aerosols are formed when PAN (peroxy acetyl nitrate) disassociates to form NO2 and HNO3 which further hydrolyzes to form pNO3? (particulate nitrate). This resulted in a high contribution of pNO3? (62%) to the total nitrogen budget over the study area. The acidity of the aerosols and snow evaluated through cation/anion ratio (C/A) indicated alkaline conditions with C/A > 2. The bicarbonates/carbonates of Mg2 + played an important role in neutralization processes of surface snow while the role of NH3 was dominant in aerosol neutralization processes. Such neutralization processes can increase the aerosol hygroscopicity causing warming. Chloride depletion in the snow was significant as compared to the aerosols, indicating two important processes, scavenging of coarse sea salt by the snow and gaseous adsorption of SO2 on the snow surface. However, a more systematic and long term study is required for a better understanding of the neutralization processes and chemical inter-conversions. 相似文献
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《Environmental Science & Policy》2002,5(5):411-420
Scientific assessments play a crucial role in advising and shaping political decisions particularly in the environmental domain. Therefore, this and the accompanying paper (Part 2) present two case studies of international environmental assessments with a perspective on internal learning processes. When carried out over a longer period of time, scientific assessments provide an opportunity for learning from past experience and from other assessment experiences which gives them the opportunity to become more powerful institutions in the process of solving environmental problems and in advising political decision-making. The paper will investigate how the assessments at hand organised their learning processes and which factors might have been influential in these processes. To answer these questions, a conceptual framework will be developed drawing particularly on literature on organisational learning. This concept will be applied to two case studies on the Intergovernmental Panel on Climate Change (IPCC) and (Part 2) on the scientific assessments under the Convention on Long-Range Transboundary Air Pollution (LRTAP). Both cases are iterative processes with significant changes of the assessment institutions over time, but they differ in their basic structures and in their effectiveness with regard to political outcomes which allows for their comparison in order to draw general conclusions. 相似文献
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The chemical composition of acid rain and its impact on lake water chemistry in Chongqing,China,from 2000 to 2020 were studied in this study.The regional acid rain intensity is affected jointly by the acid gas emissions and the neutralization of alkaline substances.The pH of precipitation experienced three stages of fluctuating decline,continuous improvement,and a slight correction.Precipitation pH showed inflection points in 2010,mainly due to the total control actions of SO2and NO 相似文献
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A modified two-dimensional Eulerian air quality model was used to simulate both the gaseous and particulate pollutant concentrations during October 21-24, 2004 in the Pearl River Delta (PRD) region, China. The most significant improvement to the model is the added capability to predict the secondary organic aerosols (SOA) concentrations because of the inclusion of the SOA formation chemistry. The meteorological input data were prepared using the CALMET meteorological model. The concentrations of aerosol-bound species such as NO3^-, NH4^+, SO4^2-, and SOA were calculated in the fine particle size range (〈2.5 μm). The results of the two-dimensional model were compared to the measurements at the ground level during the PRD Intensive Monitoring Campaign (IMC). Overall, there were good agreements between the measured and modeled concentrations of inorganic aerosol components and O3. Both the measured and the modeled results indicated that the maximum hourly O3 concentrations exceeded the China National Air Quality Standard. The predicted 24-h average SOA concentrations were in reasonable agreement with those predicted by the method of minimum OC/EC ratio. 相似文献
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Compressed natural gas(CNG)is most appropriate an alternative of conventional fuel for automobiles.However,emissions of carbon-monoxide and methane from such vehicles adversely affect human health and environment.Consequently,to abate emissions from CNG vehicles,development of highly efficient and inexpensive catalysts is necessary.Thus,the present work attempts to scan the effects of precipitants(Na_2CO_3,KOH and urea)for nickel cobaltite(Ni Co_2O_4)catalysts prepared by co-precipitation from nitrate solutions and calcined in a lean CO-air mixture at 400°C.The catalysts were used for oxidation of a mixture of CO and CH_4(1:1).The catalysts were characterized by X-ray diffractometer,Brunauer–Emmett–Teller surface-area,X-ray photoelectron spectroscopy;temperature programmedreductionandScanningelectronmicroscopycoupledwith Energy-Dispersive X-Ray Spectroscopy.The Na_2CO_3was adjudged as the best precipitant for production of catalyst,which completely oxidized CO-CH_4mixture at the lowest temperature(T_(100)=350°C).Whereas,for catalyst prepared using urea,T_(100)=362°C.On the other hand the conversion of CO-CH_4mixture over the catalyst synthesized by KOH limited to 97%even beyond 400°C.Further,the effect of higher calcination temperatures of 500 and600°C was examined for the best catalyst.The total oxidation of the mixture was attained at higher temperatures of 375 and 410°C over catalysts calcined at 500 and 600°C respectively.Thus,the best precipitant established was Na_2CO_3and the optimum calcination temperature of 400°C was found to synthesize the Ni Co_2O_4catalyst for the best performance in CO-CH_4oxidation. 相似文献
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Air quality model can be an adequate tool for future air quality prediction, also atmospheric observations supporting and emission control strategies responders. The influence of emission control policy (emission reduction targets in the national "China’s 12th Five-Year Plan (2011-2015)") on the air quality in the near future over an important industrial city of China, Xuanwei in Yunnan Province, was studied by applying the AERMOD modeling system. First, our analysis demonstrated that the AERMOD modeling system could be used in the air quality simulation in the near future for SO2 and NOx under average meteorology but not for PM10. Second, after evaluating the simulation results in 2008 and 2015, ambient concentration of SO2, NOx and PM10 (only 2008) were all centered in the middle of simulation area where the emission sources concentrated, and it is probably because the air pollutions were source oriented. Last but not least, a better air quality condition will happen under the hypothesis that the average meteorological data can be used in near future simulation. However, there are still heavy polluted areas where ambient concentrations will exceed the air quality standard in near future. In spatial allocation, reduction effect of SO2 is more significant than NOx in 2015 as the contribution of SO2 from industry is more than NOx. These results inspired the regulatory applications of AERMOD modeling system in evaluating environmental pollutant control policy 相似文献
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A field survey was conducted in a contaminated industrial site of southern Beijing,China to investigate the contents and distribution of the organochlorine pesticides(α-,β-,γ-,δ-HCH,p,p-DDT,p,p-DDE,p,p-DDD and o,p-DDT) in the profiles of soil,and a health risk assessment was carried out with CalTOX multimedia exposure model.Results showed that mean concentrations of total hexachlorocyclohexane isomers(HCHs) and total dichlorodiphenyltrichloroethane isomers(DDXs) in soils were in the range of 13.20-148.71 mg... 相似文献
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Xiaoshun Li Futian Qu Dongmei Jiang Peixin Zhu 《Frontiers of Environmental Science & Engineering in China》2009,3(3):348-353
Power generation using straw biomass has quantifiable benefits from an economic, ecological, and sociological perspective
in China. The methods used to construct the assessment models of these integrated benefits were the revenue capitalization
approach and the discounted-cash-flow approach. The results indicated that a straw power plant with the capacity of 2.50×107W and burning 1.23×105 tons of cotton straw could annually supply 1.40×108 kWh of power. However, it would not be until six years later that these results could be measured. Over the long term, the
gross benefits could reach up to 4.63×108 Yuan. Therefore, the total benefits are expected to be 1.18 × 1012 Yuan if all available straw resources are used to generate power. The policy implication showed that the long-term integrated
benefits of power generation by straw biomass outweighed the short-term benefits. This is the main incentive to use straw
biomass for power generation in the future. 相似文献
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Evaluation of oasis ecosystem risk by reliability theory in an arid area: A case study in the Shiyang River Basin, China 总被引:2,自引:0,他引:2
Ecosystem risk is a new concept in understanding environmental problems. It is important to study and develop quantitative methods for regional ecosystem risk analysis. In this study, some new indicators and methods for measuring oasis ecosystem risk were established using reliability theory. These indicators are linked to water resource, which is the key restricting factor in arid area oasis ecosystems. They have clear meanings and can also be compared in different arid area oases. A case study in the Liangzhou oasis of the Shiyang River Basin in China shows how to calculate these ecosystem risk indicators. The results of the case study are as follows: the reliability indicator, risk indicator, stability indicator, and integrated loss indicator of the Liangzhou oasis are 0.686, 0.314, 0.743, and 0.301, respectively. This means that the reliability degree of the oasis's ecosystem safety is 68.6%; the degree of risk that it is unsafe is 31.4%; the stability degree is 74.3%; and 30.1% of the oasis's area is supported by over-exploiting underground water and damaging the lower reaches of the ecosystem. This result can be used as a guide in controlling and managing ecosystem risk in the research area. 相似文献