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111.
This study investigates the energy–growth nexus for transition countries analysing Granger causality between GDP growth per capita and energy use per capita. For this purpose, 17 countries located at Central and Eastern Europe and Caucasian region are chosen and a panel dataset consisting of these countries for the available period of 1990–2011 is studied. In the study, Granger causality is investigated using bootstrapped panel causality approach proposed by Konya (Econ Modell 23(6):978–992, 2006). The approach gives consistent results in case of cross-sectional dependency and heterogeneity of slope coefficients between countries. Causality is examined for two scenarios: one with a trend and one without a trend. The results reveal that, in general, there is no causality running between energy consumption and economic growth, yet there is causality running from energy consumption to economic growth for some countries and sign of the relationship is always negative. Therefore, increases in energy consumption harm economic growth.  相似文献   
112.
Sustainable groundwater quality is a key global concern and has become a major issue of disquiets in most parts of the world including Bangladesh. Hence, the assessment of groundwater quality is an important study to ensure its sustainability for various uses. In this study, a combination of multivariate statistics, geographical information system (GIS) and geochemical approaches was employed to evaluate the groundwater quality and its sustainability in Joypurhat district of Bangladesh. The results showed that the groundwater samples are mainly Ca–Mg–HCO3 type. Principal component analysis (PCA) results revealed that geogenic sources (rock weathering and cation exchange) followed by anthropogenic activities (domestic sewage and agro-chemicals) were the major factors governing the groundwater quality of the study area. Furthermore, the results of PCA are validated using the cluster analysis and correlation matrix analysis. Based on the groundwater quality index (GWQI), it is found that all the groundwater samples belong to excellent to good water quality domains for human consumption, although iron, fluoride and iodide contaminated to the groundwater, which do not pose any significant health hazard according to World Health Organization’s and Bangladesh’s guideline values. The results of irrigation water quality index including sodium adsorption ratio (SAR), permeability index and sodium percentage (Na %) suggested that most of the groundwater samples are good quality water for agricultural uses. The spatial distribution of the measured values of GWQI, SAR, Fe (iron), EC (electrical conductivity) and TH (total hardness) were spatially mapped using the GIS tool in the study area.  相似文献   
113.
There is an increasing crisis of fresh water availability throughout the world. Sharing the available water resources in a sustainable manner among numerous stakeholders in the backdrop of this crisis is more challenging. Very often water conflicts are triggered out in this challenging scenario. These conflicts are sometimes reconciled with compacts on sharing. Water sharing compacts on both surface and aquifer resources are very common. Whether these compacts are founded on postulates of sustainability is the important question we want to investigate. Conflicts resurface when the sustainability of a compact is at stake. In this paper, we are reviewing three compacts on surface water sharing to understand their sustainability perspectives and how it has helped addressing conflicts. An introduction to various legal instruments promulgated aiming water conflict abatement is given first. Different types of water sharing agreements being signed in the current water management practice are also looked into. Theoretical background of sustainability analysis, both quantitative and qualitative, applicable in the case of water sharing models is then discussed. This is followed by specific case study analysis of three interstate water sharing agreements executed in basins of different agro-climatic regions across the world. It includes the Colorado basin (USA), Murray Darling basin (Australia) and the Parambikulam Aliyar Project (PAP) basins (India). Interstate water sharing agreement of these basins is critically examined and compared to comment on its sustainability perspective. The Murray Darling basin and its compact appear to be better in its overall considerations of sustainability. Compared to Colorado and Murray Darling, PAP requires major revisions in its sustainability context. E flows and stochastic modeling are the thrust areas of PAP that require major revision.  相似文献   
114.
In recent years, the science of foresight has been entered into planning activities by urban and regional planners and this science has impacted on planning activities. This study discusses spatial development in the south of Bushehr province using the foresight approach. The general aim of this research is to compile scenarios for the development of the mentioned study area which comprises the southern part of Bushehr province including four counties of Dayyer, Jam, Kangan and Asaluyeh. The main reason for selecting this region is their direct impressibility by major changes in the country’s oil and gas industry. This research has extremely made use of the Delphi and cross-impact analysis methods to develop foresight scenarios. Using the Delphi method, 30 initial factors were identified in the economic, political-security, linkages, science and technology, manufacturing, natural, social, infrastructural and residential issues and then the cross-impact matrix was used to investigate the impact of factors on each other. In the next step, the ranking of direct and indirect factors was determined by Micmac software and on this basis, the final refining in the selection of drivers was done. In the final stage, axes of future scenarios were presented and then the future scenarios were drawn. Results of this research indicate that two main drivers namely Iran’s international relations and energy resources are the main axes of scenarios. These two drivers have more uncertainty and higher importance than other factors and the results in four scenarios showing the possibility of each situation’s occurrence.  相似文献   
115.
The present study aims to analyse the influences of five meteorological parameters (temperature, wind speed, barometric pressure, rainfall, and solar radiations) on ground-level ozone (GLO) concentrations over the region of Ranchi Municipal Corporation (Jharkhand, India). The diurnal variation of GLO concentration and the meteorological parameters were analysed in each month to understand the associations. The results indicated that the correlation coefficients of GLO concentration with SR, AT, and DPT are found to be positive in each month and also statistically significant. But, the association between WS and GLO concentration was not uniform between the study days. Furthermore, the study also demonstrates an approach for identifying the hot spots that are having the higher level of GLO concentration. The hot spot maps were produced for each month to understand the shifting of the locations of hot spot locations. The results reveal that the hot spot locations are changes frequently in each case. Since the hot spot analysis was conducted with limited data, the presented hot spots are indicative and dependent on the meteorological conditions of the specific period and cannot be considered as a robust epidemiological study.  相似文献   
116.
117.
Malondialdehyde (MDA), a product of lipid peroxidation and biomarker of oxidative stress, is measured over the long term in spruce Picea abies needles under real conditions in three Czech mountain border areas. The trends presented collate the MDA content in spruce needles with ambient ozone, temperature and precipitation as casual, and defoliation as a subsequent factor for the period 1994-2006. We have found the overall decreasing trends in MDA and defoliation. The highest MDA and defoliation are recorded in the Jizerske, the lowest in the Krusne hory Mts. Out of the examined variables the MDA is predicted best by mean temperature in vegetation season, median of O3 concentrations and AOT40; these three variables account for 34% of MDA1 and 36% of MDA2 variability. Our hypothesis that higher ambient O3 exposure results in higher MDA contents in P. abies needles under real conditions has not been approved.  相似文献   
118.
Using the relative rate technique, rate constants for the gas-phase reactions of hydroxyl radicals with 2-chloroethyl methyl ether (k1), 2-chloroethyl ethyl ether (k2) and bis(2-chloroethyl) ether (k3) have been measured. Experiments were carried out at (298 ± 2) K and atmospheric pressure using synthetic air as bath gas. Using n-pentane and n-heptane as reference compounds, the following rate constants were derived: k1 = (5.2 ± 1.2) × 10?12, k2 = (8.3 ± 1.9) × 10?12 and k3 = (7.6 ± 1.9) × 10?12, in units of cm3 molecule?1 s?1. This is the first experimental determination of k2 and k3 under atmospheric pressure. The rate constants obtained are compared with previous literature data and the observed trends in the relative rates of reaction of hydroxyl radicals with the ethers studied are discussed. The atmospheric implications of the results are considered in terms of lifetimes and fates of the hydrochloroethers studied.  相似文献   
119.
120.
Due to hydrophobic and persistent properties, polycyclic aromatic hydrocarbons (PAHs) have a high capacity to accumulate in sediment. Sediment quality criteria, for the assessment of habitat quality and risk for aquatic life, include understanding the fate and effects of PAHs. In the context of European regulation (REACH and Water Framework Directive), the first objective was to assess the influence of sediment composition on the toxicity of two model PAHs, benzo[a]pyrene and fluoranthene using 10-day zebrafish embryo-larval assay. This procedure was undertaken with an artificial sediment in order to limit natural sediment variability. A suitable sediment composition might be then validated for zebrafish and proposed in a new OECD guideline for chemicals testing. Second, a comparative study of toxicity responses from this exposure protocol was then performed using another OECD species, the Japanese medaka. The potential toxicity of both PAHs was assessed through lethal (e.g., survival, hatching success) and sublethal endpoints (e.g., abnormalities, PMR, and EROD) measured at different developmental stages, adapted to the embryonic development time of both species. Regarding effects observed for both species, a suitable artificial sediment composition for PAH toxicity testing was set at 92.5 % dry weight (dw) silica of 0.2–0.5-mm grain size, 5 % dw kaolin clay without organic matter for zebrafish, and 2.5 % dw blond peat in more only for Japanese medaka. PAH bioavailability and toxicity were highly dependent on the fraction of organic matter in sediment and of the K ow coefficients of the tested compounds. The biological responses observed were also dependent of the species under consideration. Japanese medaka embryos appeared more robust than zebrafish embryos for understanding the toxicity of PAHs following a sediment contact test, due to the longer exposure duration and lower sensitivity of sediment physical properties.  相似文献   
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