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91.
The present study was designed with an aim to observe the effect of increasing urbanization and traffic activity on the physiology of a foliose lichen, Phaeophyscia hispidula (Ach.) Essl., collected from 13 different localities, growing in their natural habitat, in Pauri and Srinagar, two cities in the Himalayas. Six parameters i.e., Chl. a, Chl. b, total pigment, chlorophyll degradation, carotenoid and total protein content, proved the most useful to assess air pollution, were measured. Chlorophyll content and protein content are an efficient parameter to measure the air quality of a region. The study indicates that P. hispidula is pollution tolerant (adaptation) and able to withstand local emissions from vehicle exhausts.  相似文献   
92.
Considerable research indicates that a wide range of socio-economic factors influence attitudes and perceptions about environmental hazards and risks, and that social trust in those who manage a hazard is strongly correlated to judgements about risks and benefits. We suggest that there are three steps that lead to environmental risk perceptions: acquisition of information, interpretation and synthesis of different pieces of information, and understanding of that information in light of previous knowledge, perceptions, or attitudes. In this study we presented 211 college students in the sciences and non-sciences with ecological and exposure information using text, tables and maps to examine the factors that affect information acquisition and interpretation concerning ecological issues at a fictitious hazardous waste site. Students were allowed about an hour to read the materials and answer questions. The percent of students answering each question correctly varied from 4 to 82%, indicating that some questions were extremely difficult to answer. We attributed these differences to variations in the number of places information was presented (in text, tables, maps, or a combination) and the complexity of the information (how many pieces of information were required to answer the question correctly). The correlation between the number of students answering each question correctly and these combined measures (frequency, complexity) was −0.72. Thus, although there were differences in accuracy concerning ecological information as presented in this study, the major differences were accounted for by how the information was presented, and how much information was required. This suggests that risk communicators should carefully determine which ecological information is critical for the target audience, and ensure that it is presented several times (in different forms). That a lower percentage of people correctly answered questions that required synthesizing several pieces of information suggests that this complexity should be reduced where possible, or that the pieces of information should be tied clearly to the conclusion. Self-declaration of effort and perceptions of safety of the site did not markedly influence the relationship between accuracy, difficulty of finding information, and complexity of information. Other possible confounding variables (i.e., science vs non-science major) only accounted for about 27% of the variation in student’s overall score on ecological questions; age, ethnicity, and gender did not enter as significant variables. We cannot manage environmental hazards with appropriate stakeholder input unless we understand how to present environmental information to achieve a full understanding. Protection of human health and the environment requires that people understand ecological and exposure information, particularly on buffer lands.  相似文献   
93.
India has reasons to be concerned about climate change. Over 650 million people depend on climate-sensitive sectors, such as rain-fed agriculture and forestry, for livelihood and over 973 million people are exposed to vector borne malarial parasites. Projection of climatic factors indicates a wider exposure to malaria for the Indian population in the future. If precautionary measures are not taken and development processes are not managed properly some developmental activities, such as hydro-electric dams and irrigation canal systems, may also exacerbate breeding grounds for malaria. This article integrates climate change and developmental variables in articulating a framework for integrated impact assessment and adaptation responses, with malaria incidence in India as a case study. The climate change variables include temperature, rainfall, humidity, extreme events, and other secondary variables. Development variables are income levels, institutional mechanisms to implement preventive measures, infrastructure development that could promote malarial breeding grounds, and other policies. The case study indicates that sustainable development variables may sometimes reduce the adverse impacts on the system due to climate change alone, while it may sometimes also exacerbate these impacts if the development variables are not managed well and therefore they produce a negative impact on the system. The study concludes that well crafted and well managed developmental policies could result in enhanced resilience of communities and systems, and lower health impacts due to climate change.  相似文献   
94.
Breast milk is the natural and optimal food for the infants. In addition to meeting the nutritional needs, breast milk provides numerous immunological, developmental, psychological, ecological and practical advantages. The levels of the DDT and HCH residues in human milk collected from remote rural part of Agra were analysed. Beta and gamma isomers of HCH accounts for the major residue of total HCH excreted in breast milk. Delta-HCH was not detected in the samples. 95% of the samples were found to be contaminated with DDT and its metabolites. DDD was found in 88% of the samples analyzed. The total concentration of DDT and HCH were found lower than the previous studies carried out in India. The study shows the decreasing levels of these organochlorine pesticides from the environment. Total concentration of total DDT is higher than total HCH.  相似文献   
95.
India has good reasons to be concerned about climate change as it could adversely affect the achievement of vital national development goals related to socio‐economic development, human welfare, health, energy availability and use, and infrastructure. The paper attempts to develop a framework for integrated impact assessment and adaptation responses, using a recently built railroad coastal infrastructure asset in India as an example. The framework links climate change variables — temperature, rainfall, sea level rise, extreme events, and other secondary variables — and sustainable development variables — technology, institutions, economic, and other policies. The study indicates that sustainable development variables generally reduce the adverse impacts on the system due to climate change alone, except when they are inadequately applied. The paper concludes that development is a vital variable for integrated impact assessment. Well crafted developmental policies could result in a less‐GHG intensive future, enhanced adaptive capacities of communities and systems, and lower impacts due to climate change.  相似文献   
96.
Studies were conducted on the spatial distribution of different stages of the mango stone weevil, Sternochetus mangiferae (Fabr.) at Hessaraghatta farm of the Indian Institute of Horticultural Research, Bangalore, during 1983. The values of various parameters of distribution showed that the eggs are distributed as a negative binomial (contagious) distribution, whereas larvae and adults follow a positive binomial (random) distribution. It is suggested that the change in distribution may be due to the lower population densities in larval and adult stages.  相似文献   
97.
Various options are applicable for the removal of water pollutants included reverse osmosis, ion exchange, coagulation, co-precipitation, catalytic reduction, herbal filtration, electrodialysis and adsorption. This paper deals with the sorption phenomena for the removal of pollutants from drinking water. Attempts have been made to use low cost sorbents developed by pretreatment/activation/impregnation with alkalis, acids, iron oxide, manganese dioxide, ferric chloride, alum, lime, aluminum salts with natural products/indigenous minerals viz. activated alumina, activated carbon, groundnut husk, saw dust, chemically coated sand, fly ash, zeolites, clay minerals and other plant products. Application of Freundich and Langmuir isotherms were used to assess the adsorption capacity. Equilibrium isotherms were determined at optimum temperature and pH to characterize the sorption process. Statistical parameters such as mass transfer coefficients, multiple regression analysis were applied to establish the mechanism. It is suggested that the characterization of suitable, and exhausted sorbent through the application of fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray fluorescence (XRF) is essential to establish its surface bonding. Scope for safety evaluation and risk assessment to human and biosphere may provide the guideline and predication to the regulatory agencies for its sustainable use and safe disposal The ecotoxicological assessment of the leachates and low cost removal technology are discussed in this paper.  相似文献   
98.
We compared the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in a small species of fish (Central stonerollers, Campostoma anomalum) collected from East Fork Poplar Creek (EFPC) and a reference site in eastern Tennessee. Stonerollers are minnows in the Cyprinidae family that serve as prey for many carnivores in aquatic systems. Fish were collected from East Fork Poplar Creek within the U.S. Department of Energy's Y-12 National Security Complex, part of the Oak Ridge Reservation, and from a reference stretch of the Little River in East Tennessee. Whole fish were homogenized for analysis. Concentrations of all metals (except arsenic) were significantly higher in stonerollers from EFPC compared to the reference site. Mercury levels in minnows from EFPC averaged 0.4 ppm (μg/g), four times higher than the average for fish in the U.S. in general. This was higher than levels in fish from the nearby Clinch River and higher than fillets of white bass (Morone chrysops) from the same creek. Most metal levels were inversely related to size and weight of the stonerollers, perhaps due to growth dilution.  相似文献   
99.
100.
This paper estimates the future greenhousegas (GHG) and local pollutant emissions forIndia under various scenarios. Thereference scenario assumes continuation ofthe current official policies of the Indiangovernment and forecasts of macro-economic,demographic and energy sector indicators.Other scenarios analyzed are the economicgrowth scenarios (high and low), carbonmitigation scenario, sulfur mitigationscenario and frozen (development) scenario.The main insight is that GHG and localpollutant emissions from India, althoughconnected, do not move in synchronizationin future and have a disjoint under variousscenarios. GHG emissions continue to risewhile local pollutant emissions decreaseafter some years. GHG emission mitigationtherefore would have to be pursued for itsown sake in India. National energy securityconcerns also favor this conclusion sincecoal is the abundant national resource whilemost of the natural gas has to be imported.The analysis of contributing factors tothis disjoint indicates that sulfurreduction in petroleum oil products andpenetration of flue gas desulfurisationtechnologies are the two main contributorsfor sulfur dioxide (SO2) mitigation.The reduction in particulate emissions ismainly due to enforcing electro-staticprecipitator efficiency norms in industrialunits, with cleaner fuels and vehicles alsocontributing substantially. These policytrends are already visible in India.Another insight is that high economicgrowth is better than lower growth tomitigate local pollution as lack ofinvestible resources limits investments incleaner environmental measures. Ouranalysis also validates the environmentalKuznets' curve for India as SO2emissions peak around per capita GDP ofUS$ 5,300–5,400 (PPP basis) under variouseconomic growth scenarios.  相似文献   
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