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81.
The chemistry of heavy metals in sediments with respect to bio-availability and chemical reactivity is regulated by pH, texture, and organic matter contents of the sediments and specific binding form and coupled reactivity of the metals within. To focus on the metal distribution (Fe, Mn, Pb, Cd, Zn, Co, Cu, and Cr) and behavior in a fresh water aquifer system along with the ecological toxicity parameters, a four-step sequential extraction method was applied on 18 Eastern Ghats’ type sediments from fluorosis-hit Nayagarh district, India. Geo-accumulation index of metals in the sediments indicates that they are practically uncontaminated and/or less contaminated with and Fe, Mn, and Cu; contaminated to moderately contaminated with Pb, Zn, and Cr; and strongly contaminated with Cd. Rather, more than 80 % recovered Cd metal concentration in sediments constitute the labile fractions. Temporal clustering of metal fractions indicates transition metal fraction distribution claiming the sediment pH regulation. Similarly, base metal distribution accounts for organic carbon and soil conductivity due to their greater availability in exchangeable and sulfide fractions. Correlation analysis and factor analysis scores demonstrate lack of inter-relationship between transition group and base metal fractions. High fluoride concentration in ground water is associated with high sodium-bicarbonate-iron affinity with elevated pH values (i.e., >7.0) and high positive factor score with the total iron concentration in ground water.  相似文献   
82.
Seasonal and spatial phytoplankton distribution in relation to environmental factors was investigated in New Mangalore Port, a major port along the west coast of India. A well-mixed water column characterized the non-monsoon seasons, whereas it was weakly stratified during monsoon. Water quality index (TRIX) scores indicated good water quality except during pre-monsoon (inner zone surface) and monsoon (near bottom waters). Surface abundance of tychopelagic diatoms (Paralia sulcata, Melosira nummuloides, Cylindrotheca closterium, and Nitzschia sigma) was higher during non-monsoon seasons. Certain centric diatoms, e.g., Leptocylindrus danicus, P. sulcata, and Rhizosolenia imbricata, dominated during pre-monsoon (inner zone) and positively correlated with TRIX. High Skeletonema costatum and dinoflagellate abundance during the monsoon season coincided with high nutrient concentrations. Five potential toxic and fourteen harmful/bloom forming algal species were encountered at abundances below the level that can be considered as harmful to the ecosystem. In addition to a baseline database, this study highlights the potential use of certain diatom species as indicators of hydrography and water quality for monitoring dynamic coastal marine ecosystems.  相似文献   
83.
/ Environmental degradation in many hill forest regions of Asia, inhabited by indigenous/tribal communities is growing at an unprecedented rate. The case of Orissa State in eastern India is no exception. The government is of the view that the local population is responsible for forest degradation as they practice swidden cultivation and forest gathering indiscriminately to sustain their livelihoods. Based on economic merit alone, the government has undertaken some policy initiatives. Such initiatives that are meant to stop swidden cultivation have not been successful. This study recommends an integrated framework for developing a sustainable natural resource management practice for tribal communities. The framework has taken into consideration both economic and noneconomic factors in evaluating various alternatives. Furthermore, it has been applied to two tribal communities in Orissa (Juang and Saora). Based on an economic analysis comparing returns from swidden as well as wetland cultivation, it is observed that where forest degradation is not serious, wetland cultivation does not have a significant economic merit vis-à-vis swidden cultivation. However, in view of the long-term sustainability issue within ecological limits, swidden cultivation may be phased out in favor of wetland cultivation with an appropriate transition period. During this transition, government must adopt suitable policy initiatives to provide tribals tenurial rights to land, help financially in creating settled lands through terracing, introduce certain improved agroforestry techniques and train tribal people in other income-generating activities. Furthermore, all such interventions made by the government should have a strong sociocultural component in order to attract the tribal people to give up swidden cultivation.  相似文献   
84.
Soy meal, a co-product of the soy oil-based biodiesel industry, has up to 50 % protein content. The main aim of this work was to develop value-added application for soy meal. Soy meal was plasticized by glycerol and water, denatured by the addition of guanidine hydrochloride (GHCl), and then blended with poly (butylene adipate-co-terephthalate) (PBAT), petroleum based tough biodegradable polymer. Characterization by FTIR spectroscopy confirmed that soy meal was plasticized and denatured. The blends of PBAT/soy meal (SM), PBAT/plasticized soy meal and PBAT/GHCl modified plasticized soy meal (mPSM) were fabricated by industry prevalent extrusion and injection molding process. The developed bioblends were characterized by thermal and mechanical testing. One of the important outcomes of this research was that elongation of the bioblend was found to increase by 80 % after plasticization and denaturation of soy meal. Scanning electron microscope analysis showed that PBAT/mPSM blends have smoother surfaces and better internal structures than the other two.  相似文献   
85.
Unplanned industrialization and urbanization are causing health hazard mainly in developing countries. It is essential to assess the magnitude of future hazard in an industrial town. The geographical information system is a special type of tool evolved to analyse geographic data for efficient planning. In India large-scale industrialization started after independence. New industrial towns have been established and Durgapur in West Bengal is one of them. In this study an indigenously developed GIS package GRAM has been used to assess air quality in Durgapur town. Using GIS, interpolated maps have been prepared showing the distribution of five pollutants, i.e. carbon monoxide, total oxidant, nitrogen-oxide, sulfur-dioxide and suspended particulate matter. The maps have been used to find the pollutant standard index of the area. The final map shows that the PSI index is high and ranges between the unhealthy to very unhealthy category. This map has been combined with a present landuse pattern. There are three pockets of extremely poor air quality zones which generally match with industrial units. Areas around these units are the potential zones of health hazard. Large numbers of patients admitted in hospitals here suffer from obstructive diseases. Most of them belong to the working age group. This may indicate that the main work force is exposed to the health hazard due to industrial pollution.  相似文献   
86.
Using contingent valuation survey data for about 2700 households in rural Bangladesh, and applying a multinomial logit model, the paper estimates the value of arsenic-free drinking water to the rural people. The estimates indicate that the rural people in arsenic-affected areas of Bangladesh place a low value on arsenic-free drinking water. It is about 10-14 percent of the amount they are willing to pay for piped water and only about 0.2-0.3 percent of the average household income. The implication of the result is that robust but costly arsenic reduction technologies such as activated alumina technology may find little social acceptance, unless heavily subsidized.  相似文献   
87.
Environment, Development and Sustainability - Despite a large number of studies examining the relationship between corporate social responsibility disclosure (CSRD) and corporate financial...  相似文献   
88.
A significant variation in physicochemical properties of the Kalpakkam coastal waters, eastern part of India, was observed during the event of southwest to northeast monsoon transition. Increase in nitrate, total nitrogen, and silicate concentrations were noticed during post-transition period. Ammonia concentration was at peak during transition period as compared to pre- and post-transition periods. Hypo-saline condition (~23 psu) was observed during post-transition as the surface water salinity decreased by ~10 psu from the pre-transitional values. Turbidity, suspended particulate matter, phosphate and total phosphorous values decreased marginally, coinciding with northward to southward current reversal. A drastic decrease (eightfold) in chlorophyll-a concentration was observed in the coastal water during post-transition period.  相似文献   
89.
Chemical modification of soy protein with monomers such as maleic anhydride, glycidyl methacrylate and styrene was accomplished using reactive extrusion technology. Thermal and mechanical properties of the modified soy protein plastics were characterized with differential scanning calorimetry (DSC), a dynamic mechanical analyzer (DMA) and a United Testing System load frame. It was found that the denaturation temperature and the glass transition temperature of soy protein plastic changed. In addition, the tensile properties of modified soy protein plastic improved. Attenuated total reflection Fourier transform infrared (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) were used to characterize the structure of modified soy proteins. A suggestion of the interaction between soy protein and functional group in functional polymers is given. Through the in-situ interaction between the polymer and soy protein plastic, the mechanical properties of the soy protein plastic can be adjusted and controlled.  相似文献   
90.
Manufacturing of manganese (Mn) compounds, their industrial applications as well as mining overburden, has generated a potential environmental pollutant. Occupational exposure to elevated levels of Mn occurs during mining, welding, smelting and other industrial anthropogenic sources. Chronic and acute exposure of this metal pollutant leads to adverse consequences and is clinically categorized by various symptoms of neurotoxicity including cognitive, psychiatric symptoms, Parkinson's disease, extra pyramidal signs, manganism, dystonia, and motor system dysfunction. The aim of this review is to summarize the possible mechanism underlying Mn compounds-mediated neurotoxicity leading to neurodegenerative diseases. Our review endeavours to examine recent advances in research on Mn-related environmental pollution, Mn-induced poisoning, molecular mechanisms underlying Mn-induced neurotoxicity with case studies as well as current approaches employed for treatment and prevention of Mn exposure.  相似文献   
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