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121.
ABSTRACT

This case study was conducted in Himalayan watershed to understand traditional farming and socio-economic status of the people in Kumaon Himalaya, Uttarakhand, India. In spite of high literacy rate in this area, their livelihood security is reliant on traditional farming practices that include agroforestry beside forest produce. More than 85% farming is rainfed and managed in a traditional way. Land holding size owned by farmers in the area extended from 0.57 to 2.57 ha but majority of farmers (51–80%) had farms of size less than 0.50 ha. The study revealed that forests provided 73–79% of required energy from fuelwood and more than 81% fodder. Agroforestry, livestock (dairy and poultry/goat rearing) and labour employment are the major sources of income to the people in the watershed. The income of people was positively correlated with livestock rearing and traditional farming.  相似文献   
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Synthetic pyrethroids are the recent major class of broad spectrum, photostable, organic insecticides used in agricultural, domestic and veterinary applications and now account for more than 30% of global insecticide use. Cypermethrin is metabolized and eliminated significantly more slowly by fish than by mammals or birds, which may explain this compound's high toxicity in fish compared to other organisms. The present communication deals with histoanatomical alterations in the gonads of a local fresh water food fish, Channa punctatus exposed to 0.033 ppm (96 hr LC50 X 1/10) concentration of a synthetic pyrethroid, devicyprin (cypermethrin 25%) in aquatic medium of aged tap water for 15, 30 and 45 days respectively. In testis, exposure dependent histological damage has been observed in terms of vacuolization, condensation of spermatogonic cells, distortion of tubular epithelium, shrinkage of interstitial cells and general inflammatory responses. Longest exposure of 45 days has resulted in peculiar starry-sky appearance of the testicular tissue. Gross histo-anatomy of ovarian tissue reveals epithelial lesions, inflammatory responses, stromal hemorrhage, increased interstitium and shrinkage of yolk vesicles towards periphery These findings are quite suggestive of reproductive impairments leading to delayed gonadal maturity and adversely affecting processes of sperm production and ovulation and thus, the fish production.  相似文献   
124.
Compositional changes to air quality from coal mining are not only the most visible impact from these activities on the environment, they can also immediately affect the health of mine professionals and adjoining populations. The presence of gases and suspended solids emitted by mining activities affects the human respiratory system and decreases production in mines. This article summarizes a case study of several Northern Coalfields Limited (NCL) coal mines with an emphasis on particulate matter (PM) to report the status of air quality connected to coal production and overburden removal. The concentrations of sulfur dioxide (SO2), nitrogen oxides (NOx), and suspended particulate matter (SPM) reported in the literature are also summarized in table form to allow comparisons to the permissible standards set by the Indian Central Pollution Control Board (CPCB) and other standards used around the world. An up‐to‐date status of air quality at coal mines is compared for mines located in different parts of India. Subsequently, all coal mines were divided into different classes in regard to the severity of their emissions. These classes are, in increasing order of severity, green, yellow, red, and black. SPM measurements were tabulated in regard to concentration and composition. Our article concludes with the recommendation that an environmental impact assessment (EIA) to be conducted to better characterize changes in the environment from mining emissions to develop integrated mitigation measures and to identify additional parameters to define air quality at mines.  相似文献   
125.
Environmental Science and Pollution Research - Steel slag is a major industrial waste in steel industries, and its dissolution behavior in water needs to be characterized in the larger context of...  相似文献   
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Both Streptomyces species and mold species have previously been isolated from moisture-damaged building materials; however, an association between these two groups of microorganisms in indoor environments is not clear. In this study, we used a culture-independent method, PCR-denaturing gradient gel electrophoresis (PCR-DGGE), to investigate the composition of the Streptomyces community in house dust. Twenty-three dust samples each from two sets of homes categorized as high-mold and low-mold based on mold-specific quantitative PCR analysis were used in the study. Taxonomic identification of prominent bands was performed by cloning and sequencing. Associations between DGGE amplicon band intensities and home mold status were assessed using univariate analyses as well as multivariate recursive partitioning (decision trees) to test the predictive value of combinations of bands intensities. In the final classification tree, a combination of two bands was significantly associated with mold status of the home (p?=?0.001). The sequence corresponding to one of the bands in the final decision tree matched a group of Streptomyces species that included Streptomyces coelicolor and Streptomyces sampsonii, both of which have been isolated from moisture-damaged buildings previously. The closest match for the majority of sequences corresponding to a second band consisted of a group of Streptomyces species that included Streptomyces hygroscopicus, an important producer of antibiotics and immunosuppressors. Taken together, the study showed that DGGE can be a useful tool for identifying bacterial species that may be more prevalent in mold-damaged buildings.  相似文献   
128.
Environmentally safe disposal of end-of-life (EoL) or discarded mobile phone is a serious problem on account of their ever increasing number and toxic metals contents. In the present work, metal toxicity of mobile phone plastics, printed wire boards (PWBs) and batteries were assessed through dynamic batch leaching using Milli Q (MQ) water. Phone plastics failed Toxicity Characterization Leaching Procedure (TCLP) and Waste Extraction Test (WET) for Pb as the cumulative amount of Pb leached from plastics (5.33 mg/l) exceeded the regulatory limits (5.0 mg/l) used in characterizing a waste as hazardous. Similarly, the average cumulative amount (21.83 mg/l) of Ni leached from PWBs exceeded the regulatory limit of 20 mg/l and thus PWBs failed WET. Metals leached from batteries in small amounts (Cr: 0.40 mg/l and Ni: 0.15 mg/l). The presence of Fe in the batteries and its precipitation as oxides/hydroxides in the leaching solution hindered the leaching of other metals in MQ water. Both plastics and PWBs should be treated as hazardous waste and should not be disposed in open landfills. Further, MQ water leaching could provide good simulation of metals leaching from the mobile phones disposed at landfill sites.  相似文献   
129.
Environmental Science and Pollution Research - Regional averages of radon, thoron, and associated decay product concentration are reported to be higher than their respective global averages in...  相似文献   
130.
Established groundwater contaminants such as chlorinated solvents and hydrocarbons have impacted groundwater at hundreds of thousands of sites around the United States and have been responsible for multibillion dollar remediation expenditures. An important question is whether groundwater remediation for the emerging contaminant class comprised of per‐ and polyfluoroalkyl substances (PFAS) will be a smaller, similar, or a larger‐scale problem than the established groundwater contaminants. A two‐pronged approach was used to evaluate this question in this paper. First, nine quantitative scale‐of‐remediation metrics were used to compare PFAS to four established contaminants: chlorinated solvents, benzene, 1,4‐dioxane, and methyl tert‐butyl ether. These metrics reflected the prevalence of the contaminants in the U.S., attenuation potential, remediation difficulty, and research intensity. Second, several key challenges identified with PFAS remediation were evaluated to see similar situations (qualitative analogs) that have been addressed by the remediation field in the past. The results of the analysis show that four out of nine of the evaluated quantitative metrics (production, number of potential sites, detection frequency, required destruction/removal efficiency) indicate that the scale of PFAS groundwater remediation may be smaller compared to the current scale of remediation for conventional groundwater contaminants. One attenuation metric, median plume length, suggests that overall PFAS remediation could pose a greater challenge compared to hydrocarbon sites, but only slightly larger than chlorinated volatile organic compounds sites. The second attenuation metric, hydrophobic sorption, was not definitive regarding the potential scale of PFAS remediation. The final three metrics (regulatory criteria, in‐situ remediation capability, and research intensity) all indicate that PFAS remediation might end up being a larger scale problem than the established contaminants. An assessment of the evolution of groundwater remediation capabilities for established contaminants identified five qualitative analogs for key PFAS groundwater remediation issues: (a) low‐level detection analytical capabilities; (b) methods to assess the risk of complex chemical mixtures; (c) nonaqueous phase dissolution as an analog for partitioning, precursors, and back diffusion at PFAS sites; (d) predictions of long plume lengths for emerging contaminants; and (e) monitored natural attenuation protocols for other non‐degrading groundwater contaminants. Overall the evaluation of these five analogs provided some comfort that, while remediating the potential universe of PFAS sites will be extremely challenging, the groundwater community has relevant past experience that may prove useful. The quantitative metrics and the qualitative analogs suggest a different combination of remediation approaches may be needed to deal with PFAS sites and may include source control, natural attenuation, in‐situ sequestration, containment, and point‐of‐use treatment. However, as with many chlorinated solvent sites, while complete restoration of PFAS sites may be uncommon, it should be possible to prevent excessive exposure of PFAS to human and ecological receptors.  相似文献   
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