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Effects of methyl mercuric chloride (MMC) on the blood parameters of Swiss mice (Mus musculus) were studied. The mice received an initial dose of MMC (24 mg kg(-1) body wt) as intraperitoneal injection followed by a second similar dose on the 14th day of the first dose administration. Significant (p < or = 0.001) decreases in haemoglobin content, red blood cell (RBC) count and haematocrit value were observed in the MMC injected mice when compared to the control mice. The effect of the second dose was severe, after which no significant recovery in the values of these parameters was observed. The result also showed a high degree of mercury accumulation in the blood of the MMC exposed mice. Interesting features were marked in the erythrocyte morphology of the exposed mice. An initial shrinkage followed by swelling of the cells was observed after each injection. The outline of the exposed cells was irregular with beak like or small finger like projections. Rupturing and disintegration of the erythrocyte membrane, leading to erythrolysis, were also noticed. 相似文献
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Singh R Joshi PK Kumar M Dash PP Joshi BD 《Environmental monitoring and assessment》2009,155(1-4):555-567
Geospatial tools supported by ancillary geo-database and extensive fieldwork regarding the distribution of tiger and its prey in Anchankmar Wildlife Sanctuary (AMWLS) were used to build a tiger habitat suitability model. This consists of a quantitative geographical information system (GIS) based approach using field parameters and spatial thematic information. The estimates of tiger sightings, its prey sighting and predicted distribution with the assistance of contextual environmental data including terrain, road network, settlement and drainage surfaces were used to develop the model. Eight variables in the dataset viz., forest cover type, forest cover density, slope, aspect, altitude, and distance from road, settlement and drainage were seen as suitable proxies and were used as independent variables in the analysis. Principal component analysis and binomial multiple logistic regression were used for statistical treatments of collected habitat parameters from field and independent variables respectively. The assessment showed a strong expert agreement between the predicted and observed suitable areas. A combination of the generated information and published literature was also used while building a habitat suitability map for the tiger. The modeling approach has taken the habitat preference parameters of the tiger and potential distribution of prey species into account. For assessing the potential distribution of prey species, independent suitability models were developed and validated with the ground truth. It is envisaged that inclusion of the prey distribution probability strengthens the model when a key species is under question. The results of the analysis indicate that tiger occur throughout the sanctuary. The results have been found to be an important input as baseline information for population modeling and natural resource management in the wildlife sanctuary. The development and application of similar models can help in better management of the protected areas of national interest. 相似文献
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Joshi PK Kumar M Paliwal A Midha N Dash PP 《Environmental monitoring and assessment》2009,149(1-4):371-376
The main focus of the paper is to assess the land use/ land cover (LULC) change in northern Chhattisgarh due to industrialization using remote sensing and Geographical Information System (GIS). The impact was assessed using an information extraction method applied to temporal satellite data (LANDSAT and IRS scenes) in GIS domain. For assessing the impact on natural resources, the classification scheme was restricted to (1) Forest patches ((a) completely cleared, (b) partially cleared, (c) least affected), (2) Non-Forest ((d) completely changed, (e) least changed), (3) Industrial/Mining area, and (4) River. Over the three decades 22.22% of forests have been completely cleared and converted to industrial setup. Another 25% is completely cleared and 10% is degraded. Around 4% of agricultural area is totally affected due to industrial activity. Random assessment of plant distribution (Trees, Shrubs and Herbs) indicates significant changes in the herb distribution directly related to distance gradient form the industrial/mining setup. Visual recording, socio-economic survey and satellite data also helped in delineation of extent of environmental pollution in forest and non-forest areas. The paper presents methodology for the environmental impact assessment. 相似文献
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Indicator and probability kriging methods for delineating Cu, Fe, and Mn contamination in groundwater of Najafgarh Block, Delhi, India 总被引:1,自引:0,他引:1
Partha Pratim Adhikary Ch. Jyotiprava Dash Renukabala Bej H. Chandrasekharan 《Environmental monitoring and assessment》2011,176(1-4):663-676
Two non-parametric kriging methods such as indicator kriging and probability kriging were compared and used to estimate the probability of concentrations of Cu, Fe, and Mn higher than a threshold value in groundwater. In indicator kriging, experimental semivariogram values were fitted well in spherical model for Fe and Mn. Exponential model was found to be best for all the metals in probability kriging and for Cu in indicator kriging. The probability maps of all the metals exhibited an increasing risk of pollution over the entire study area. Probability kriging estimator incorporates the information about order relations which the indicator kriging does not, has improved the accuracy of estimating the probability of metal concentrations in groundwater being higher than a threshold value. Evaluation of these two spatial interpolation methods through mean error (ME), mean square error (MSE), kriged reduced mean error (KRME), and kriged reduced mean square error (KRMSE) showed 3.52% better performance of probability kriging over indicator kriging. The combined result of these two kriging method indicated that on an average 26.34%, 65.36%, and 99.55% area for Cu, Fe, and Mn, respectively, are coming under the risk zone with probability of exceedance from a cutoff value is 0.6 or more. The groundwater quality map pictorially represents groundwater zones as ??desirable?? or ??undesirable?? for drinking. Thus the geostatistical approach is very much helpful for the planners and decision makers to devise policy guidelines for efficient management of the groundwater resources so as to enhance groundwater recharge and minimize the pollution level. 相似文献
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Dash Devi Prasad Dash Aruna Kumar Sethi Narayan 《Environmental science and pollution research international》2022,29(21):31252-31269
Environmental Science and Pollution Research - Overutilized hydro-energy production through non-sustainable mode is detrimental for both the economy and the environment. Intermittent consumption of... 相似文献
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东北三省农田生态系统碳排放时空分异特征及驱动因素研究 总被引:4,自引:0,他引:4
根据2000—2014年东北三省碳排放的相关数据,结合空间探索性分析及地理加权回归等模型方法,对研究区农田生态系统碳排放量的空间集聚性、差异性及其重要驱动因素进行研究.结果表明:东北三省农田生态系统碳排放量存在比较显著的全局空间正相关,自相关性在整体上表现出逐渐增强的趋势,到2014年全局Moran's I指数达到最高值0.3395.在局部空间相关关系上,东北三省农田生态系统碳排放量的高-高区域集中在黑龙江省和吉林省,低-低地区主要集中在辽宁省,表现出不平衡的发展格局.人均GDP对农田生态系统碳排放有负效应,总人口数对农田生态系统碳排放的影响从正效应转变为负效应,化肥施用对农田生态系统碳排放影响程度的空间分布格局发生了较大变化,代表生产技术水平和能源消耗的农业化肥施用量和农业机械总动力因素对农田生态系统碳排放的影响较大,东北三省农田生态系统碳排放和农业机械总动力相关程度有逐渐趋同的趋势. 相似文献
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Dash K Saha K Pandey AK Jain AK Mukherjee A 《Journal of environmental biology / Academy of Environmental Biology, India》2003,24(3):265-269
Light microscopic and ultra-structural studies of the lymphoid tissues such as blood immunocytes, spleen and pronephros of the freshwater catfish, Clarias batrachus, were carried out. The peripheral blood showed nucleated erythrocytes, total leucocytic count (TLC) more than that observed in mammalian blood and leucocytes with morphological appearance similar to the mammalian white blood cells (WBCs). The spleen and pronephros showed presence of numerous lymphocytes, monocytes and nucleated red blood cells (RBCs) along with hemosiderin-containing macrophages. The morphology of lymphoid organs of the catfish has been discussed in light of the evolution of the immune system in this class of vertebrates. 相似文献
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Summary A comparative study of Survey of India topo-maps of 1929 and land satellite imageries in False Colour Combination (FCC) of
1975 indicates a loss of 43% and 46% of the reserved forest around Sambalpur and Jharsuguda respectively, besides other forest
types in a radius of twenty miles. Deforestation is found to be an accelerating process where the rate of loss is estimated
to be more during 1970–75 and 1960–70 in comparison to 1950–60 from a semilogarithmic trend curve between 1929 and 1975. This
curve also fits to a hypothesis that the rate of deforestation is faster after 1950 (after developmental plan periods came
into force).
An analysis of the climatic data indicates a decrease in rainfall and number of rainy days, and morning relative humidity.
The mean minimum and maximum temperature, evening relative humidity and atmospheric pressure show increasing trends.
Relationships between forest loss and climatic parameters are significant for morning relative humidity, rainy days, maximum
temperature and atmospheric pressure.
Considering the loss of storage capacity of the Hirakud reservoir due to severe deforestation in the catchment area, suggestions
are given for natural forest preservation.
Arttabandhu Mishra graduated in Science (Zoology Honours) and Education from Utkal University; postgraduated from Berhampur
University, India. At present he is a Lecturer in School of Life Sciences, Sambalpur University and Secretary of Orissa Environmental
Consciousness Society. His fields of interests are Productivity and Energetics of Forest Ecosystems, Environmental Education
and Community Education. He has published seven papers on the above fields and a number bf popular articles. He tries to use
folk literature as media to carry scientific messages.
Madhab C. Dash, obtained his B.Sc. (Hens), M.Sc. from Utkal University, India and Ph.D. from University of Calgary, Canada.
At present he is Professor and Head, School of Life Sciences, Sambalpur University, a fellow of the Zoological Society of
India, the National Institute of Ecology and the National Academy of Sciences, India. His major areas of research and writing
are on the functional role of soil organisms in the decomposer subsystem of ecosystems, He has published seventy-five papers
on taxonomy, biology, population ecology, metabolic functions, energy flow modelling, role in soft fertility and waste conditioning
ability of Oligochaetes, nematodes, protozoa and soil microorganisms. Professor Dash has contributed specialised chapters
in major treaties published by Cambridge University Press, UK; John Wiley and Sons, USA; and Academic Press, New York, USA. 相似文献