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81.
The classical approach of assessing sustainability with respect to its three underlying pillars, ecological, economic, and social, is adopted in this paper, with an added emphasis on estimating the simultaneous effects of each pillar on the other two. The paper assesses the impact of policy-driven changes in cultivation practices in five districts in the south-western Indian state of Karnataka. A comparative statics analysis using a simultaneous equations model is developed to capture the stability of each pillar into the future and their concurrent interactive impacts and trade-offs. Ecological and economic impacts of policies favoring organic farming are estimated to be uniformly significant and positive in the study districts. However, the impact on socio-cultural criteria is subjective to the eco-regional context. Cost savings, through producing organic inputs on-farm, maximizes synchrony among the three pillars vis-à-vis sourcing these inputs from the market. With more reliance on organic inputs, better prospects are estimated for small and rain-fed farms compared to large and irrigated farms.  相似文献   
82.
A large variety of ornamental and decorative items are manufactured from bone waste by various unorganized sectors in India. An initial survey indicated that workers were exposed at various phases of final product. The subjects (12 industrial units) were tested for total suspended particulate matter (TSPM), particulate matter <10  $\upmu $ m (PM10), and particulate matter <2.5  $\upmu $ m (PM2.5). Prevalent levels of TSPM ranged between 2.90 and 5.89 mg m???3. Respirable fractions of occupational dust as PM10 and PM2.5 were found in the range of 0.30?C2.08 and 0.26?C0.50 mg m???3, respectively. Cytotoxicity study was conducted using hemolysis as a sensitive marker. In an in vitro study, rat RBCs were exposed to the concentration of 25?C1,000  $\upmu $ g/ml for 15?C120 min. A considerable variation was observed in the hemolytic activity of samples collected from different areas. At 500  $\upmu $ g/ml concentration, the hemolytic activity (12 h) was found to be in the range of 18?C25%. Due to limitation in sample mass of respirable fractions, only one concentration (100  $\upmu $ g/ml/2 h) was used for comparative study on hemolysis of RBCs caused by PM10 and PM2.5. Interestingly, the hemolytic activity was more at PM2.5 than PM10 and TSPM. These results suggest that the respirable particles are capable of reaching deep into the respiratory system. The finding is significant notably when there are no standards available in occupationally exposed populations. This is the first such study. Data could be of importance to policy makers and regulators.  相似文献   
83.
The Atlantic Slope Consortium (ASC) is a project designed to develop and test a set of indicators in coastal systems that are ecologically appropriate, economically reasonable, and relevant to society. The suite of indicators will produce integrated assessments of the condition, health and sustainability of aquatic ecosystems based on ecological and socioeconomic information compiled at the scale of estuarine segments and small watersheds. The research mandate of the ASC project is the following:
Using a universe of watersheds, covering a range of social choices, we ask two questions:
  • ? How “good” can the environment be, given those social choices?
  • ? What is the intellectual model of condition within those choices, i.e., what are the causes of condition and what are the steps for improvement?
As a basis for compiling ecological indicators, a watershed classification system was required for the experimental design. The goal was to develop approximately five categories of watersheds for each physiographic province, utilizing landscape and land use parameters that would be predictive of aquatic resource condition. All 14-digit Hydrologic Unit Code (HUC) watersheds in the Mid-Atlantic region would then be classified according to the regime. Five parameters were utilized for the classification: three land cover categories, consisting of forested, agricultural, and urban, median slope or median elevation, and total variance of land covers in 1-km-radius circles positioned on all stream convergence points in a specified 14-digit?HUC watershed. Cluster analysis utilizing these five parameters resulted in approximately five well-defined watershed classes per physiographic province. The distribution of all watersheds in the Mid-Atlantic region across these categories provides a unique report on the probable condition of watersheds in the region.  相似文献   
84.
Since the last few decades, terrestrial diversity is found to be under stress due to the contamination by various chemicals and gases of aquatic and agricultural media. The bioaccumulation of these compounds at certain concentrations in different tissues produces histopathological changes leading to behavioral changes in target animals. This study focused on terrestrial molluscan slug, Semperula maculata, against lethal concentrations of mercury chloride (HgCl2). Bioaccumulation of Hg was highest in ovotestis, while lowest in the molluscan penis. Histopathological changes were observed in the cellular arrangement of reproductive organs. Alterations in the penis and the dart gland included dilated unicellular, multicellular glands, and muscular dystrophy, dilated peripheral glandular cells, respectively; dilation being maximal in the prostate gland. Ovotestis showed depleted number of gametocytes. Vacoulized pre-vitellogenic oocytes with early vitellogenic oocytes were noted under light microscopy. Mercury produced toxicity on secretory functions and lowered the rate of reproduction in animals. Evidence indicates that Hg produced gamete degeneration, impacted reproductive capacity and survival of this species in the ecosystem.  相似文献   
85.
86.
Many environmental systems and infrastructure systems are monitored using a set of indicator values that assess several aspects of site condition. The values of different indicators often convey different comparative messages for the study sites. The comparability between sites is analyzed within the theory of partially-ordered sets and visualized with Hasse diagrams. This paper demonstrates that properties of partially-ordered sets and the conversion of indicator scores into a rank matrix provide a manager or decision-maker with valuable information that would be lost if the monitored indicator data were aggregated only into a single index. Stream stability assessment data from 49 bridge crossing sites in the United States are used to demonstrate these techniques in prioritization and identification of restoration and maintenance needs of stream channels at bridge crossings.  相似文献   
87.
We propose a novel tool for testing hypotheses concerning the adequacy of environmentally defined factors for local clustering of diseases, through the comparative evaluation of the significance of the most likely clusters detected under maps whose neighborhood structures were modified according to those factors. A multi-objective genetic algorithm scan statistic is employed for finding spatial clusters in a map divided in a finite number of regions, whose adjacency is defined by a graph structure. This cluster finder maximizes two objectives, the spatial scan statistic and the regularity of cluster shape. Instead of specifying locations for the possible clusters a priori, as is currently done for cluster finders based on focused algorithms, we alter the usual adjacency induced by the common geographical boundary between regions. In our approach, the connectivity between regions is reinforced or weakened, according to certain environmental features of interest associated with the map. We build various plausible scenarios, each time modifying the adjacency structure on specific geographic areas in the map, and run the multi-objective genetic algorithm for selecting the best cluster solutions for each one of the selected scenarios. The statistical significances of the most likely clusters are estimated through Monte Carlo simulations. The clusters with the lowest estimated p-values, along with their corresponding maps of enhanced environmental features, are displayed for comparative analysis. Therefore the probability of cluster detection is increased or decreased, according to changes made in the adjacency graph structure, related to the selection of environmental features. The eventual identification of the specific environmental conditions which induce the most significant clusters enables the practitioner to accept or reject different hypotheses concerning the relevance of geographical factors. Numerical simulation studies and an application for malaria clusters in Brazil are presented.  相似文献   
88.
人群感知是气候变化适应行为形成的重要信息基础,基于对中国北方草地草甸草原、典型草原、荒漠草原、草原化荒漠、沙地、农牧交错带等地区1292个牧户的问卷访谈,分2轮调查研究了不同草地类型地区牧民对气候变化的感知,与气候实值比较分析,并研究了牧民气候变化感知的偏差途径,结果表明:1980~2009年间研究区温度变化倾向率为0.63℃/10a(P0.05);温度较强的趋势性与牧民对其感知的分歧存在偏差,降水无明显变化与不同地区牧民感知明确的趋势性判断存在偏差;受草场变化等环境信息的传导是气候变化感知偏差形成的重要原因,其中,降水感知与环境感知之间具有较强的关系,存在明显的传导过程,而温度感知的传导性不明显;通过Probit模型分析显示,气候变化传导感知与否主要与牧户距离行政中心距离、户主年龄、教育背景、载畜水平、草畜资源等因素有关.  相似文献   
89.
Thermocatalytic degradation of high density polyethylene (HDPE) was carried out using acid activated fire clay catalyst in a semi batch reactor. Thermal pyrolysis was performed in the temperature range of 420–500 °C. The liquid and gaseous yields were increased with increase in temperature. The liquid yield was obtained 30.1 wt% with thermal pyrolysis at temperature of 450 °C, which increased to 41.4 wt% with catalytic pyrolysis using acid activated fire clay catalyst at 10 wt% of catalyst loading. The composition of liquid products obtained by thermal and catalytic pyrolysis was analyzed by gas chromatography-mass spectrometry and compounds identified for catalytic pyrolysis were mainly paraffins and olefins with carbon number range of C6–C18. The boiling point was found in the range of commercial fuels (gasoline, diesel) and the calorific value was calculated to be 42 MJ/kg.  相似文献   
90.
Mumbai, a highly populated city in India, has been selected for air quality mapping and assessment of health impact using monitored air quality data. Air quality monitoring networks in Mumbai are operated by National Environment Engineering Research Institute (NEERI), Maharashtra Pollution Control Board (MPCB), and Brihanmumbai Municipal Corporation (BMC). A monitoring station represents air quality at a particular location, while we need spatial variation for air quality management. Here, air quality monitored data of NEERI and BMC were spatially interpolated using various inbuilt interpolation techniques of ArcGIS. Inverse distance weighting (IDW), Kriging (spherical and Gaussian), and spline techniques have been applied for spatial interpolation for this study. The interpolated results of air pollutants sulfur dioxide (SO2), nitrogen dioxide (NO2) and suspended particulate matter (SPM) were compared with air quality data of MPCB in the same region. Comparison of results showed good agreement for predicted values using IDW and Kriging with observed data. Subsequently, health impact assessment of a ward was carried out based on total population of the ward and air quality monitored data within the ward. Finally, health cost within a ward was estimated on the basis of exposed population. This study helps to estimate the valuation of health damage due to air pollution.

Implications: Operating more air quality monitoring stations for measurement of air quality is highly resource intensive in terms of time and cost. The appropriate spatial interpolation techniques can be used to estimate concentration where air quality monitoring stations are not available. Further, health impact assessment for the population of the city and estimation of economic cost of health damage due to ambient air quality can help to make rational control strategies for environmental management. The total health cost for Mumbai city for the year 2012, with a population of 12.4 million, was estimated as USD8000 million.  相似文献   

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