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1.
This paper examines the perspectives of the implementation of a demand-oriented policy concerning residential water use, which covers almost 70% of urban water. Water demand, water pricing policy, as well as building capacity are examined and evaluated in order to investigate the current situation in urban water management in the city of Volos with reference to residential water use. The application of IWR-MAIN model in order to estimate future water needs and form different scenarios for sustainable water resources management together with a field survey in various water issues conducted in 966 citizens of the city of Volos justify the urgent need for the adoption of a demand driven policy.  相似文献   

2.
Analysis and Case Study of Duststorms in the Beijing Area   总被引:4,自引:0,他引:4  
Dust weather conditions with strong wind often occur in Beijing during spring. The number of duststorms in Beijing has declined since 1954. In the last two years, however, the number of duststorms in Beijing has increased drastically due to frequent cold air movements and the deteriorated ecological environment. The heaviest duststorm in the last decade in Beijing occurred on 6 April 2000. It was caused by the development of a high-level small trough along with strong northwest wind behind a large trough that moved eastward and developed a strong cold air system. A non-hydrostatic meso-scale numerical model (MM5) gave a good forecast to the duststorm's major features and movement. Simulated results showed that there was a strong vertical ascending motion with a strong positive vorticity center in mid and low level. The mesoscale structure's formation and development and movement were consistent with the passage and moving direction of the duststorm. At the same time, the trajectories of air particles during this duststorm event and another case (on 27 March 2000) were estimated and analyzed, which had the comparable results with the real situation and the trajectory monitored by meteorological satellite. The trajectories analysis could help us study the transport track and sand source to some extent.  相似文献   

3.
The design of efficient water allocation systems depends, among other factors, on economic issues and, above all, on a reliable estimate of the economic value of water. In this paper the hedonic price method is utilized to reveal the implicit value of irrigation water by analyzing agricultural land values in Chalkidiki, a typical rural area in Greece. The method was applied to a sample of both irrigated and nonirrigated properties and the value of irrigation water was estimated by disaggregating the total price of each parcel of land, obtained through a local survey. Results show that, apart from typical value attributes, the agricultural characteristics of the land, including irrigation water availability, have a significant influence on land prices.  相似文献   

4.
Alkaline tailings from a salt work and a soda plant have been pumped into the southernmost part of Traunsee at Ebensee for many decades. A survey in 1981 showed an accumulation of more than 3 × 106 m3 alkaline mud in the Bay of Ebensee and the existence of slumping structures and turbidites in the profundal zone of the lake. A new survey of the industrial tailings has been performed in 1999. Compared to the earlier survey, the accumulation in the Bay of Ebensee has grown to >4 × 106 m3, which suggests an average yearly input of 90 000 m3. Slumping structures and turbidites document the unstable situation of the tailings near the waste inlet. The lake area occasionally affected by the turbidity currents in the profundal zone has increased to 19%. Within the central profundal area these tailings reach <1 m in thickness.  相似文献   

5.
In this research, a novel thermosensitive nanosphere polymer (TNP) was synthesized by copolymerization of N-isopropylacrylamide with 3-allyloxy-1,2-propanediol for the removal of diazinon from water. The characterization of the synthesized adsorbent has been performed by Fourier transform infrared spectrometer, scanning electron microscopy and elemental analysis. Batch adsorption method was performed to investigate the influences of various parameters like pH, temperature and contact time on the adsorption of diazinon. The equilibrium adsorption data of diazinon by TNP was studied by Langmuir, Freundlich, Temkin and Redlich–Peterson model. According to equilibrium adsorption results, the Langmuir, Freundlich and Temkin constants were evaluated to be 0.912 (L/mg), 7.916 (mg/g) (L/mg)1/n and 2.494 respectively at pH 7 and room temperature. Based on Redlich–Peterson model analysis, the equilibrium data for the adsorption of diazinon was conformed well to the Langmuir isotherm model. This method was successfully applied for removal of diazinon from environmental samples. Moreover, in reusing of TNP, the sorption capacity was maintained without any significant change after 10 cycles of sorption–desorption process.  相似文献   

6.
7.
This study was carried out in 32 communities neighbouring four Ramsar wetlands in Northern Greece. In particular, it concerns the study of local residents' attitude regarding the ways of management and exploitation of the wetlands and their sociological features, using the opinion poll method (1600 questionnaires were distributed). The aim of this investigation is the evaluation of findings for planning of effective management and conservation policy of wetlands, incorporating the opinions of local residents. Further protection of the wetlands, awareness of local residents of the value of wetlands, tourism or agriculture development (in some cases), as well as more governmental support, became obvious results from this research.  相似文献   

8.
The consumption of bottled water in Italy began in the 1970s. Since then, this usage has grown considerably, also as a result of changes in habits. The environmental impact as a result of the water production chain is very significant; it would be considered, for example, the use of plastic bottles, the consumption of oil in the production of the bottles, the emission of air from the vehicles that transport the bottles, non-recycled plastic packaging, etc.In this study, considering the comparison between two situations, use of bottled water and use of water kiosk (WK), an environmental and economic impact evaluation has been done. The study considered the production of a WK in a town with 9000 inhabitants, which supplies controlled, still and sparkling water, with an organoleptic quality higher than tap water coming from the aqueduct. In particular, taking into consideration the environmental aspects, specific attention was paid both to CO2 emissions and PET bottle waste reduction. The economic impact evaluation was carried out from the consumer’s point of view. In order to provide a supply service that was economically sustainable, a calculation was done with the aim of determining a specific fee for the supplied water. Moreover, a comparison has been made between quality parameters achieved with the analysis of water from aqueducts with the limits established in the Italian legislation and the parameters of several Italian water brands.The study has the aim at considering the opportunity to follow a different people’s habits, closer to the concept of sustainability, reducing the environmental charge related to the realization, transport and consumption of plastic water bottles without significant reduction of the quality of the service and with convenient and interesting economic implications. In fact the results of the study show that the alternative of WKs is more efficient in economic and environmental terms respect to the use of bottled water.  相似文献   

9.
A 12-year record of water quality data for runoff from a spruce forested hillslope with podzolic soils shows the impacts of conifer harvesting and replanting in relation to nitrate generation and its influence on surface water acidification. With felling, nitrate increases from a background of 18 Eq/l to about 50 Eq/l after 1 to 2 years and then declines to background levels over the next 1 to 2 years and to lower concentrations thereafter. This change is mirrored by an acidification process as manifest by a change in Gran alkalinity, acid neutralization capacity (ANC) and aluminium concentrations as well as pH. For example, Gran alkalinity and ANC, which start at negative concentrations prior to felling (about –20 and –50 Eq/l, respectively), become more negative (–30 and –100 Eq/l, respectively) at high nitrate concentrations. Correspondingly, pH decreases from about 4.7 to 4.5 and aluminium concentrations increase from about 14 to 16 M. Subsequently, the acidification is reversed as nitrate concentrations decline and after five years post-felling the system has higher pH, Gran alkalinity and ANC together with lower aluminium concentrations than even before the felling took place (the post-felling values are about 4.9, -15 Eq/l, –20 Eq/l and 7 M/l, respectively).Other determinands show clear changes over time. For example, there is a marked increase in sodium and chloride prior to and around the time of felling (200 to 300 and 230 to 400 Eq/l, respectively), with a subsequent decline in concentration to pre-felling and to lower values of around 160 and 170 Eq/l, respectively, thereafter. This change is probably associated with abnormally high inputs of sea-salts from the atmosphere during the first quarter of the year of felling, and dilution thereafter, rather than a direct consequence of the felling activity itself: this change in sea salt loading has had an impact on stream acidity. Dissolved organic carbon and iron also change with concentrations increasing over time (60 to 200 and 1.0 to 1.5 M/l, respectively) and this mirrors a general pattern observed across the Plynlimon catchments irrespective of whether or not there has been felling activity.The implications of the findings are discussed in relations to environmental management and hydrochemical processes.  相似文献   

10.
针对以热电企业为核心的产业链构建在城市发展中遇到的问题,以YL工业园区为研究载体,基于耗散结构理论,建立了以热电企业为核心的循环经济产业链,并对产业链上、下游企业在结构、资源配置上进行了整合优化.通过YL工业园区的实证研究,对构建包含循环型生物医药、水泥建材、食品饮料加工、装备制造和纺织服装型的经济产业链提出了具体建议.  相似文献   

11.
Gelatin-Zr(IV) phosphate composite (GT/ZPC) was synthesized by sol–gel method. Different techniques viz. Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray powdered diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used for the characterisation of GT/ZPC composite ion exchanger. The ion exchange capacity (IEC) of GT/ZPC was observed to be better (1.04 meq g?1) than its inorganic counterpart (0.64 meq g?1). The pH studies revealed the monofunctional nature of GT/ZPC with one inflection point. The distribution studies showed that the GT/ZPC was highly selective for Cd2+ as compare to other metal ions. The environmental applicability of ion exchanger has been analysed for binary separations of metal ions using column method. Cd2+ was effectively removed from synthetic mixture of metal ions (Zn2+, Pb2+, Ni2+, Co2+ and Cu2+).  相似文献   

12.
Biodegradation of poly (ethyl glyoxylate) (PEtG), a functionalized polyacetal, was investigated over 6?month according to ASTM 5988-96 modified method and compared to micronized cellulose. More than 95?% of the polymer was converted into CO2 over that period attesting the biodegradability of PEtG. The degradation by-products toxicity and ecotoxicity were evaluated. Toxicity was checked using an innovant non-mammalian toxicological model using the nematode Caenorhabditis elegans. Ecotoxicity was performed using a plant growth test with cress (Lepidium Sativum), and barley (Hordeum vulgare). In all cases, results concluded on the harmlessness of PEtG and relative by-products.  相似文献   

13.
The practice of incorporating certain waste products into highway construction and repair materials (CRMs) has become more popular. These practices have prompted the National Academy of Science, National Cooperative Highway Research Program (NCHRP) to research the possible impacts of these CRMs on the quality of surface and ground waters. State department of transportations (DOTs) are currently experimenting with use of ground tire rubber ( crumb rubber) in bituminous construction and as a crack sealer. Crumb rubber asphalt concrete (CR-AC) leachates contain a mixture of organic and metallic contaminants. Benzothiazole and 2(3H)-benzothiazolone (organic compounds used in tire rubber manufacturing) and the metals mercury and aluminum were leached in potentially harmful concentrations (exceeding toxic concentrations for aquatic toxicity tests). CR-AC leachate exhibited moderate to high toxicity for algae ( Selenastrum capriconutum) and moderate toxicity for water fleas ( Daphnia magna). Benzothiazole was readily removed from CR-AC leachate by the environmental processes of soil sorption, volatilization, and biodegradation. Metals, which do not volatilize or photochemically or biologically degrade, were removed from the leachate by soil sorption. Contaminants from CR-AC leachates are thus degraded or retarded in their transport through nearby soils and ground waters.  相似文献   

14.
A new version (v1.7) of the Integrated Nitrogen in CAtchments model(INCA) was applied to the northern boreal Simojoki river basin (3160 km2) in Finland. The INCA model is a semi-distributed, dynamic nitrogen (N) process model which simulates N transport and processes in catchments. The INCA model was applied to model flow and seasonal inorganic N dynamics of the river Simojoki basin over the period 1994–1996, and validated for two more years. Both calibration and validation of the model were successful. The model was able to simulate annual dynamics of inorganic N concentrations in the river. The effects of forest management and atmospheric deposition on inorganic N fluxes to the sea in 2010 were studied. Three scenarios were applied for forestry practices and two for deposition. The effects of forest cutting scenarios and atmospheric deposition scenarios on inorganic N flux to the sea were small. The combination of the maximum technically possible reduction of N deposition and a decrease of 100% in forest cutting and peat mining areas decreased NO3 --N flux by 6.0% and NH4 +-N flux by 3.1%.  相似文献   

15.
酚焦油资源化技术研究(Ⅱ)--裂解产物的分离   总被引:2,自引:0,他引:2  
开发出一种精馏与钠盐法相结合的分离酚焦油裂解产物的新工艺,裂解产物经精馏,蒸出异丙苯等轻组分、苯酚馏分和共沸物。共沸物中加入氢氧化钠,分离出酚钠盐和苯乙酮。轻组分和酚钠盐均返回苯酚、丙酮生产装置。裂解产物中有用物质的收率为92.91%,苯乙酮的收率为82.38%,其纯度大于98%。  相似文献   

16.
Polyhydroxybutyrate is a type of biopolymer that can be produced from hydrolyzed polysaccharide materials and could eventually replace polypropylene and polyethylene, being biodegradable, biocompatible and produced from renewable carbon sources. However, polyhydroxybutyrate is not still competitive compared to petrochemical polymers due to their high production costs. The improvement of the production processes requires a search for new alternative raw materials, design of the pretreatment technique and improvement in the fermentation and separation steps. In addition, if the polyhydroxybutyrate production is coupled into a multiproduct biorefinery it could increase the economic and environmental availability of the process through energy and mass integration strategies. In this work alternatives of energy and mass integrations for the production of polyhydroxybutyrate into a biorefinery from residual banana (an agro-industrial waste) were analyzed. The results show that the energetic integration can reduce up to 30.6% the global energy requirements of the process and the mass integration allows a 35% in water savings. Thus, this work demonstrates that energy and mass integration in a biorefinery is a very important way for the optimal use of energy and water resources hence decreasing the production cost and the negative environmental impacts.  相似文献   

17.
Synthesis of sodium alginate-g-poly(acrylamide-co-N-methylacrylamide) [S-III], sodium alginate-g-poly(N-methylacrylamide-co-N,N-dimethylacrylamide) [S-II], sodium alginate-g-poly(acrylamide-co-N,N-dimethylacrylamide) [S-I]. Sodium alginate-g-poly(N,N-dimethylacrylamide) [SAG-g-PDMA] and sodium alginate-g-poly(acrylamide) [SAG-g-PAM] were prepared by solution polymerization technique using potassium peroxydisulfate as the initiator at 70?°C in water medium. The graft copolymers were characterized by FTIR and NMR (1H and 13C) spectroscopy, SEM and XRD studies. All the five graft copolymers were used to remove Pb(II) ions from the aqueous solution and also in flocculation studies of kaolin clay (1.0 wt%), silica (1.0 wt%) and iron ore slime (0.25 wt%) suspensions. A comparative studies of all the five graft copolymers were also made in both the two cases. The Pb(II) ion removal capacity of all the graft copolymers follows the order S-III?>?SAG-g-PAM?>?S-II?>?SAG-g-PDMA?>?S-I. But the flocculation performance of the graft copolymers follows the order S-II?>?S-I?>?S-III?>?SAG-g-PDMA?>?SAG-g-PAM. S-III was also used for the competitive metal ion removal with Hg(II), Cd(II), Cu(II) and Zn(II). Pb(II) adsorption of S-III (the best Pb(II) ion adsorber) follows pseudo second order rate equation and Langmuir adsorption isotherm.  相似文献   

18.
Industrialization and urbanization along the coastal population centers have brought great changes in the land cover and material fluxes from watersheds to receiving bays and estuaries. We have embarked a multiyear research project on “Watersheds Nutrient Loss and Eutrophication of Jiaozhou Bay” for the period of 2000 to 2004, funded by the Natural Science Foundation of China to examine human influence on the marine sector of ecosystem. Jiaozhou Bay, located in the southern part of Shandong Peninsula, was selected because of the existence of long-term hydrographic and meteorological records since the 1930s and recent observations on the marine ecological variables. We have made extensive and periodic measurements on the water movement, nutrients, phytoplankton, and microbe in water column and bottom sediments. Box and 3-dimensional hydrodynamic models were developed and utilized to understand the evolution of eutrophic status with time. It was found that primary productivity has suffered from silica depletion followed by phosphate, and the dominance of large phytoplankton has been replaced by small-size communities. These ecosystem changes were brought by the changes in the relative contribution among major pathways and concentrations, owing to the human activities in the watershed. Eight articles in this volume reported various aspects of the linkage between watershed human activities and ecosystem for the Jiaozhou Bay as the initial outcome of this project.  相似文献   

19.
Current cost estimates for the assessment and remediation of environmental contamination at facilities operated by the U.S. Department of Energy (DOE) are based largely on assumptions, with a resulting high level of uncertainty. Therefore, consistent and reliable methods for estimating the uncertainty inherent in the estimates are of vital importance. This article presents an approach and format for estimating contingency in DOE's Environmental Restoration Program. The method involves an analysis of risk factors having a potential to affect the cost of the major elements in the estimate. Application of the contingency analysis to a project site is included in the discussion.  相似文献   

20.
Traunsee, an oligotrophic Alpine lake, has suffered from inputsof industrial tailings (soda- and salt-mining industries) forseveral decades. The effects of the industrial sludges on thespatial distribution of the littoral and profundal invertebratefauna was investigated along three transects at five dates. Inthe littoral zone, no negative impacts were found. A distinctgradient in faunal composition and diversity was, however,observed along a profundal transect relative to the distance fromthe waste emission. Near the industrial input, the enhanced pH,the substrate instability, and the poor sediment quality forsubstrate- and deposit-feeders were the main factors that loweror prohibit colonization of the industrial sludges. Along atransitional zone between the waste emission and the deepestbasin, recolonization was delayed, but did occur as soon aslayers of a few mm natural sediment seal the sludge. Mobile,epibenthic organisms are the first to settle these areas, whereasrecolonization by tube-building oligochaetes and chironomidsrequires thicker sealings of the industrial sludges. Differencesin the abundance of benthic invertebrates at different profundalsites were not only related to the waste emission, but also tothe influence of the main tributary, the River Traun. Theenhanced availability of allochthonous organic matter wasprobably responsible for high densities of tubificids near theinlet in the South of Traunsee. Moreover, a higher proportion oftolerant oligochaete and ostracod species in the lower profundaloutside the influence of the industrial tailings was interpretedas reflecting the increased trophy of Traunsee in the 1970s,which forced sensitive species to shift to the upper profundalwhen the oxygen climate deteriorated.  相似文献   

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