Economic Modelling in Sustainability Science: Issues,Methodology, and Implications

Sustainability science is a new branch of human knowledge. It is necessary to model sustainability science based on a framework consisting of the interactions of society, ecology, the environment and the economy. This paper develops such a model, the SEEOSG model, containing the essential structural relationships that incorporate the environmental and economic conditions required for sustainability. The model is solved as a dynamic optimisation problem. This optimal growth model of ecology and economic growth enables us also to analyse the issues which are specific to sustainability science such as the ecologically sustainability and inter-generational equity implications of economic activities and policies. In the model results growth maximisation goals appear to be fraught with difficulties such as infeasibility and non-sustainability. The results also suggest also that an equilibrium ecological and economic system does not sustain over a very long period of time unless appropriate actions are taken. Readers should send thier comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

Climate change in Asia: issues and policy options

This article provides a brief review of some of the policy issues facing the Asian region with respect to climate change and its economic consequences. The environmental consequences of Asia's economic rise threaten the future growth of the region. Despite recent economic expansion, Asia will be one of the areas of the world most vulnerable to climate change. While Asia currently contributes moderately to greenhouse gas emissions, the potential for increases in emissions is significant. National and regional policy options, including abatement and adaptation, are examined as strategies for tackling the likely effects of climate change. This study recommends that national initiatives that have no 'regrets' properties be a priority area for further research so that they can be implemented as soon as possible. It is envisaged that in the short to medium term, identifiable no regrets policies can be a useful tool for reducing emissions and vulnerability to climate change in developing regions such as Asia.     

Health risks associated with heavy metals in the drinking water of Swat, northern Pakistan

The concentrations of heavy metals such as Cd, Cr, Cu, Mn, Ni, Pb and Zn were investigated in drinking water sources （surface and groundwater） collected from Swat valley, Khyber Pakhtunkhwa, Pakistan. The potential health risks of heavy metals to the local population and their possible source apportionment were also studied. Heavy metal concentrations were analysed using atomic absorption spectrometer and compared with permissible limits set by Pakistan Environmental Protection Agency and World Health Organization. The concentrations of Cd, Cr, Ni and Pb were higher than their respective permissible limits, while Cu, Mn and Zn concentrations were observed within their respective limits. Health risk indicators such as chronic daily intake （CDI） and health risk index （HRI） were calculated for adults and children separately. CDIs and HRIs of heavy metals were found in the order of Cr 〉 Mn 〉 Ni 〉 Zn 〉 Cd 〉 Cu 〉 Pb and Cd 〉 Ni 〉 Mn 〉 Cr 〉 Cu 〉 Pb 〉 Zn, respectively. HRIs of selected heavy metals in the drinking water were less than 1, indicating no health risk to the local people. Multivariate and univariate statistical analyses showed that geologic and anthropogenic activities were the possible sources of water contamination with heavy metals in the study area.     

Accumulation of Pb, Cu, and Zn in native plants growing on contaminated sites and their potential accumulation capacity in Heqing, Yunnan

Phytoremediation is one of the cost-effective and environmental friendly technologies used to remove contaminants from contaminated soils,which has been intensively studied during the last decade.Presently,few economical and effective remediation methods are available for the remediation of Pb contaminated sites.This study was conducted to assess the potential of 19 plants growing on contaminated sites in Pb mine area.Plants and associated soil samples were collected and analyzed for total metal concentrati...     

Hydrogeochemical assessment of carcinogenic and non-carcinogenic health risks of potentially toxic elements in aquifers of the Hindukush ranges,Pakistan: insights from groundwater pollution indexing,GIS-based,and multivariate statistical approaches

Environmental Science and Pollution Research - Globally, potentially toxic elements (PTEs) and bacterial contamination pose health hazards, persistency, and genotoxicity in the groundwater aquifer....     

Comparison of cellular and molecular cytotoxic mechanisms of Cochlodinium polykrikoides in isolated trout and rat hepatocytes

Harmful algal blooms produced by the marine ichthyotoxic dinoflagellate Cochlodinium polykrikoides are responsible for mass mortalities of wild and farmed fish globally. This study compared the cytotoxic mechanisms of C. polykrikoides total extract on both trout and rat liver hepatocytes. Trout hepatocytes were more sensitive than rat hepatocytes against C. polykrikoides extract. The effective concentration 50 after 3 hour incubation (EC50_3hr) concentrations found for C. polykrikoides extract in trout and rat hepatocytes (i.e., 50% membrane lysis in 3 hr) were Eq. 1 cell/ml and Eq. 240 cell/ml, respectively. C. polykrikoides extract exposure in both isolated trout and rat hepatocytes resulted in membrane lysis, reactive oxygen species formation, glutathione depletion, collapse of mitochondrial membrane potential, ATP depletion, increase in adenosine diphosphate (ADP)/adenosine triphosphate (ATP) ratio, cytochrome c release into the hepatocyte cytosol, and activation of caspases cascade. Trout hepatocyte toxicity was also associated with lysosomal membrane injury. Mitochondrial permeability transition in both trout and rat hepatocytes produced cytochrome c release from the mitochondrial intramembrane space into the cytosol. Thus, the cytochrome c release triggered activation of caspase-3 and apoptosis. Finally, data demonstrated that C. polykrikoides extract may induce more apoptotic phenotype in rat than trout hepatocytes, which in the latter favored predominantly necrotic mode of cell death.     

限制性片段长度多态性分析(ARDRA)方法对重金属污染土壤中细菌群落多样性的研究

限制性片段长度多态性分析(ARDRA)是用限制性内切酶消化扩增后的细菌16S rDNA,通过凝胶电泳分析微生物种群多样性的分子标记技术,该技术在微生物生态学领域有着广泛的应用.实验采用2种途径评价了这种方法应用于研究土壤中细菌种群多样性的可行性.通过对未污染土壤细菌16S rDNA的克隆,获得了经内切酶HaeⅢ消化的不同16S rDNA的ARDRA类型,并对测序的19个克隆子建立了系统发育树.此外,还对不同Cd和Pb污染水平的土壤微生物进行了群落水平上的ARDRA分析.结果表明,5 mg·kg-1 Cd和500 mg·kg-1 Pb污染对微生物群落组成有一定影响,但此范围内的重金属含量对微生物群落多样性没有相关性影响.     

Downward shortwave radiation estimation and spatial assessment on sites over complex terrain applying integrative approach of MTCLIM-XL,interpolation, RS and GIS

Downward shortwave radiation (DSR) is a highly variable solar source on spatiotemporal basis and essential for energy and agriculture systems, while its calculations are helpful in the environment-related studies, climatology, and monitoring fire risk. Statistical methods developed to extrapolate values of climatic variables and radiation could fail to generate reliable findings of DSR over a complex terrain without considering local topographic factors. In the present study, we proposed an integrative approach of MTCLIM-XL extrapolation with remote sensing (RS) and geographic information system (GIS) to estimate real-time DSR and its spatial potential over surfaces of contrasting elevated sites on a mountainous terrain of Quetta (Pakistan).Based on methodological approach, remote sensing data product of high-resolution DEM (SRTM 30m) was processed to extract topographic data, and meteorological data were obtained from a base site, Subsequently, MTCLIM-XL executed the simulation to calculate the daily-based DSR (W/m²).Spatial distribution of DSR was generated by applying deterministic interpolation with complementing quantification of Hillshade analysis for spatially obstructive surfaces, and resultant spatial hotspot-based potential was assessed on basis of specified threshold level (above 250 W/m² = 2 kW h/m²) over the specified area. We observed usable potential of DSR at target sites and its spatial distribution during the study period of 2015 to April 2016. Using EUMETSAT CMSAF data as a standard, the validation demonstrates agreeable results of low RMSE and high correlation coefficient values for selected sites, except some sites with relatively high elevations and irregular gradients. Analysis of solar zenith angle to evaluate its inverse relation with increment in DSR values shows agreeable high inverse relation, while the negative trend for only some sites features relatively high rugged topography. In conclusion, MTCLIM-XL with RS and GIS integration manifests as a reliable approach for estimation and spatial potential assessment-based exploration of DSR over complex terrain having no ground data, while prospectively it will complement to the environment-related studies on local to mesoscale.     

Use of constructed wetland for the removal of heavy metals from industrial wastewater

This study was conducted to investigate the effectiveness of a continuous free surface flow wetland for removal of heavy metals from industrial wastewater, in Gadoon Amazai Industrial Estate (GAIE), Swabi, Pakistan. Industrial wastewater samples were collected from the in-let, out-let and all cells of the constructed wetland (CW) and analyzed for heavy metals such as lead (Pb), cadmium (Cd), iron (Fe), nickel (Ni), chromium (Cr) and copper (Cu) using standard methods. Similarly, samples of aquatic macrophytes and sediments were also analyzed for selected heavy metals. Results indicate that the removal efficiencies of the CW for Pb, Cd, Fe, Ni, Cr, and Cu were 50%, 91.9%, 74.1%, 40.9%, 89%, and 48.3%, respectively. Furthermore, the performance of the CW was efficient enough to remove the heavy metals, particularly Cd, Fe, and Cu, from the industrial wastewater fed to it. However, it is suggested that the metal removal efficiency of the CW can be further enhanced by using proper management of vegetation and area expansion of the present CW.     

Treatment Technology Evaluation for Aqueous Metal and Cyanide Bearing Hazardous Wastes (F007)

As a result of recent developments In the area of hazardous waste management, the U.S. Environmental Protection Agency Is evaluating the performance of various technologies for the treatment and/or the destruction of certain wastes that are presently being disposed of In landfills and surface Impoundments. As a part of this program, the University of Cincinnati Is testing currently available treatment technologies that are applicable to metal- and cyanidebearing hazardous wastes at the U.S. EPA Test and Evaluation Facility In Cincinnati, Ohio. The following unit processes have been evaluated: alkaline chlorlnatlon, lime precipitation/ flocculation/settllng, multi-media filtration, anlon exchange, and cation exchange. Examination of several process configurations, utilizing the above-mentioned unit processes, did not produce any treatment train that could prevent codepositlon of cyanides and metals In the sludges when the feed stream contained mixed metals and complexed cyanides. It was also determined that special anion exchange resins are capable of removing the compiexed cyanides that are not destroyed by alkaline chlorlnatlon. Concentration of each of the metals in the final effluent from the cation exchange unit was less than 0.4 mg/L.