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1.
Radon measurements have been carried out in groundwater of Himachal Pradesh and Punjab states, India. Radon concentration values in potable water show a wide range of variation from source to source and from place to place. Generally, radon concentration values in thermal springs groundwater have been found to be higher than the values from other sources.  相似文献   

2.
It is well established that some areas of Himachal Pradesh (H.P.) state of India situated in the environs of the Himalayan mountains are relatively rich in uranium-bearing minerals. Some earlier studies by our group have indicated high levels of radon (>200 Bq m(-3)) in the dwellings. It is in this context that an indoor radon/thoron survey has been carried out in selected villages of four districts in the state of H.P. This survey has been conducted as a part of a national, coordinated project using twin chamber dosemeter cups designed by the Environmental Assessment Division (EAD), Department of Atomic Energy, Govt. of India. The track-etch technique is used for calibration of plastic detector LR-115 type-II which are employed for recording alpha tracks due to radon/thoron and their daughters. Year long radon/thoron data have been collected for seasonal correlations of indoor radon/thoron in the dwellings. The indoor radon levels have been found to vary from a minimum value of 17.4 Bq m(-3) to a maximum value of 140.3 Bq m(-3). The indoor thoron levels vary from a minimum value of 5.2 Bq m(-3) to a maximum value of 131.9 Bq m(-3). The year average dose rate for the local population varies from 0.03 microSv h(-1) to 0.83 microSv h(-1). The annual exposure dose to inhabitants in all the dwellings lies below the upper limit of 10 mSv given in ICRP-65.  相似文献   

3.
Water quality assessment of Lake Pandu Bodhan, Andhra Pradesh State, India   总被引:1,自引:0,他引:1  
A systematic investigation of variations in some nutrient levels at Pandu Lake from August 2002 to July 2004 was carried out. The untreated domestic wastes from various parts of Bodhan town are directly discharged into Pandu Lake leading to gross pollution. Therefore present investigation was under taken to assess the magnitude of sewage pollution by monitoring key water quality parameters dissolved oxygen, biological oxygen demand, alkalinity, calcium, nitrates and phosphates etc. Monthly water samples were collected from three different sampling stations. Low Dissolved oxygen and high biological oxygen demand, elevated Nitrates and Phosphates levels were found, which gives the information about conversion of this water body from oligotrophic to eutrophic nature. Phosphates were found to be in the range of 0.9 to 4.0 mg/L. Nitrates were found to be higher in Pandu Lake and their number is more in summer, and suitable explanation was given. Nitrates were found to be in range between 24.8mg/L to 71.2mg/L. Data on various chemical characteristics vary at different sites in different months in Pandu Lake. Some of the characteristics like Dissolved Oxygen, Biological Oxygen Demand, Nitrates, Phosphates and nutrient loading are contributing to eutrophication process in this lake and the lake seems to be eutrophic through out the year.  相似文献   

4.
The present study deals with the limnobiotic status of three selected lakes of Himachal Pradesh using physicochemical and biological parameters (especially phytoplankton and zooplankton) over a period of 2 years. One hundred forty-eight species belonging to nine groups of phytoplankton and 79 species belonging to five groups of zooplankton were identified from the lakes. Trophic level and the pollution status of the lakes were assessed upon the basis of Shannon diversity index (H′), species richness index (S), and physicochemical parameters. Plankton population size was correlated with biotic and abiotic parameters (pH, alkalinity, temperature, dissolved oxygen, transparency, phosphate, chloride, and nitrate). The present investigation revealed that the distribution of plankton species depended upon the physicochemical parameters of the environment. Based on water quality standards given by the Central Pollution Control Board, the water quality was between “A–B” at Prashar wetland, “C–D” at Kuntbhyog Lake, and “D–E” at Rewalsar Lake. The results from the present study indicated that the potential of planktons as bioindicators of trophic status is very high.  相似文献   

5.
Residues dynamics of Endosulfan (525.00 g a.i. ha(-1)), Imidacloprid seed treatment (21 g a.i. kg(-1)), Lambdacyhalothrin (75.00 g a.i. ha(-1)) and Spiromesifen (225.00 g a.i. ha(-1)) in nectar and pollen of mustard, Brassica juncea (L.) Czern. grown in Himachal Pradesh (India) were determined through bioassay (using Drosophila melanogaster Meig. as test organism) and GC (Gas chromatographic) and HPLC (High performance liquid chromatographic) methods. In general chromatographic methods were more sensitive for the determination of above given pesticides compared to bioassay method. Average recoveries in nectar samples varied between 82.85 and 88.90% by bioassay and 91.20 and 93.55% by chromatographic techniques. In pollen samples, recoveries varied between 81.44 and 86.44% by bioassay and 88.50 and 91.30% by chromatographic methods. Imidacloprid residues were neither found in nectar nor in pollen samples at the time of sampling i.e. 50% of flowering. The order of average half life of residues was: Lambdacyhalothrin (12.45 h) < Spiromesifen (19.99 h) < Endosulfan (27.49 h) for nectar and Spiromesifen (9.69 h) < Lambdacyhalothrin (12.44 h) < Endosulfan (17.84 h) for pollen samples. It was found that Imidcloprid seed treatment was practically harmless to honey bees, whereas a waiting period of 5 days must be observed on crops sprayed with these chemicals during blooms to avoid any accidental hazards to honey bees.  相似文献   

6.
Trace metals biogeochemistry of Kumaun Himalayan Lakes,Uttarakhand, India   总被引:1,自引:0,他引:1  
The increasing urbanization, along with tourism, has posed a major threat to the Kumaun Himalayan Lakes, Uttarakhand, India. The total metal concentration in the water, interstitial water, and sediments along with the metal fractionation studies were carried out to understand the remobilization of the trace metals from the sediments of the lakes. The high concentration of the metals in the water column of the lakes generally decreases with depth and the metals release from the sediment is mainly due to the prevalence of anoxic condition at the sediment–water interface and sediment column. The sediment shows that metals Fe and Cr are derived from detrital source, whereas Co, Ni, and Zn are derived mainly from the organic matter dissolution. The sparse correlation of the trace metals with Ti shows most of the metals have chiefly re-precipitated from the water column. The metals speciation studies also supports that metals experience a high rate of anoxic dissolution and their precipitation onto the sediments are determined by the sediment composition and organic matter content. The high concentration of manganese in the interstitial water in the lakes indicates dissolution of organic matter. The released manganese is adsorbed/precipitated as carbonate phase (Nainital Lake) and oxide pahse (in other lakes). The study shows that the trace metals are regenerated from the sediments due to oxyhydroxide dissolution and organic matter decomposition.  相似文献   

7.
Trace elements are essential for human health. However, excess concentrations of these elements cause health disorders. A study has been carried out in Visakhapatnam environs, Andhra Pradesh, India to ascertain the causes for the origin and distribution of iron content in the groundwaters. Fifty groundwater samples are collected and analyzed for iron. The content of iron ranges from 400 to 780 μg/l. A comparison of groundwater data with rock and soil chemistry suggests that the concentration of iron (400–530 μg/l) in the groundwaters is derived from the rocks and soils due to geogenic processes. This concentration is taken as a natural occurrence of iron in the groundwaters of the study area for assessing the causes for its next higher content (>530 μg/l). Relatively higher concentration of iron (540–550 μg/l) is observed at some well waters, where the wells are located nearby municipal wastewaters, while the very high concentration of iron (610–780 μg/l) is observed in the industrially polluted groundwater zones, indicating the impact of anthropogenic activities on the groundwater system. These activities mask the concentration of iron caused by geogenic origin. Hence, both the geogenic and anthropogenic activities degrade the groundwater quality. Drinking water standards indicate that the iron content in all the groundwater samples exceeds the permissible limit (300 μg/l) recommended for drinking purpose, causing the health disorders. Necessity of close monitoring of groundwater quality for assessing the impact of geogenic and anthropogenic sources with reference to land use/land cover activities is emphasized in the present study area to protect the groundwater resources from the pollution.  相似文献   

8.
Land use impact on soil quality in eastern Himalayan region of India   总被引:1,自引:0,他引:1  
Quantitative assessment of soil quality is required to determine the sustainability of land uses in terms of environmental quality and plant productivity. Our objective was to identify the most appropriate soil quality indicators and to evaluate the impact of six most prevalent land use types (natural forestland, cultivated lowland, cultivated upland terrace, shifting cultivation, plantation land, and grassland) on soil quality in eastern Himalayan region of India. We collected 120 soil samples (20 cm depth) and analyzed them for 29 physical, chemical, and biological soil attributes. For selection of soil quality indicators, principal component analysis (PCA) was performed on the measured attributes, which provided four principal components (PC) with eigenvalues >1 and explaining at least 5 % of the variance in dataset. The four PCs together explained 92.6 % of the total variance. Based on rotated factor loadings of soil attributes, selected indicators were: soil organic carbon (SOC) from PC-1, exchangeable Al from PC-2, silt content from PC-3, and available P and Mn from PC-4. Indicators were transformed into scores (linear scoring method) and soil quality index (SQI) was determined, on a scale of 0–1, using the weighting factors obtained from PCA. SQI rating was the highest for the least-disturbed sites, i.e., natural forestland (0.93) and grassland (0.87), and the lowest for the most intensively cultivated site, i.e., cultivated upland terrace (0.44). Ratings for the other land uses were shifting cultivation (0.60)?>?cultivated low land (0.57)?>?plantation land (0.54). Overall contribution (in percent) of the indicators in determination of SQI was in the order: SOC (58 %)?>?exch. Al (17.1 %)?>?available P (8.9 %)?>?available Mn (8.2 %)?>?silt content (7.8 %). Results of this study suggest SOC and exch. Al as the two most powerful indicators of soil quality in study area. Thus, organic C and soil acidity management holds the key to improve soil quality under many exploitatively cultivated land use systems in eastern Himalayan region of India.  相似文献   

9.
Carbon Sequestration Potential of Indian Forests   总被引:3,自引:0,他引:3  
The forestry sector can not only sustain its carbon but also has the potential to absorb carbon from the atmosphere. India has maintained approximately 64 Mha of forest cover for the last decade. The rate of afforestation in India is one of the highest among the tropical countries, currently estimated to be 2 Mha per annum. The annual productivity has increased from 0.7 m3 per hactare in 1985 to 1.37 m3 per hectare in 1995. Increase in annual productivity directly indicates an increase in forest biomass and hence higher carbon sequestration potential. The carbon pool for the Indian forests is estimated to be 2026.72 Mt for the year 1995. Estimates of annual carbon uptake increment suggest that our forests and plantations have been able to remove at least 0.125 Gt of CO2 from the atmosphere in the year 1995. Assuming that the present forest cover in India will sustain itself with a marginal annual increase by 0.5 Mha in area of plantations, we can expect our forests to continue to act as a net carbon sink in future.  相似文献   

10.
Total arsenic in four different growth forms of lichens growing on old monuments in the city of Mandav, Dhar district of Madhya Pradesh, India was analyzed. Among the different growth forms, foliose lichens were found to accumulate higher amounts of arsenic followed by leprose form. The squamulose and crustose form accumulates the lower concentration of arsenic and ranged between 0.46 ± 0.03 and 20.99 ± 0.58 μg g???1 dry weight, while the foliose and leprose lichens have ranges from 10.98–51.95 and 28.63–51.20 μg g???1 dry weight, respectively. The substrate having high arsenic ranges also exhibit higher ranges of arsenic on lichens growing on them. The cyanolichens exhibit higher concentration of arsenic than the green photobiont-containing squamulose form. The higher concentration of arsenic was found at site having past mining activities. LSD (1%) shows significant difference for As concentration in lichens thallus between the selected sites and species both.  相似文献   

11.
The groundwater quality assessment for the drinking and irrigation purpose is carried out in the Kandivalasa River Sub Basin covered with khondalitic suite (Garneti ferrous, Sillimanite, Gneiss) of rocks, near Cheepurupalli town of Vizianagaram district, Andhra Pradesh, India. The analysis for the groundwater quality for drinking has shown the slightly alkaline nature and high values of alkalinity in the study area. A very high concentration of total dissolved solids value is observed at one pocket where there has been contamination by many fertilizer industries located nearby the study area. The groundwater is highly affected by the nitrate. Higher fluoride values are obtained at few pockets. Most of the samples in the study area are categorized as very hard category. According to the Piper trilinear diagram, it can be observed that the carbonate hardness and secondary salinity have occupied at major part of study area. From the analysis of sodium adsorption ratio, salinity hazard, sodium percentage, residual sodium carbonate, and Kelly’s ratio, all the groundwater samples except at few locations fell under the category of good to excellent for irrigation. The prepared integrated groundwater quality maps for the drinking purpose and agricultural purposes are indicating that, by and large, the low-lying areas are having poor groundwater quality than the uplands for drinking as well as agricultural needs which means that the groundwater quality of the basin is following the topography.  相似文献   

12.
Arsenic in the soil and water of eastern districts of Uttar Pradesh (Ballia and Ghazipur) was estimated. Survey results revealed that arsenic in soil samples ranged from 5.40 to 15.43 parts per million (ppm). In water samples, it ranged from 43.75 to 620.75 parts per billion (ppb) which far exceeded the permissible limit of 10 ppb as recommended by the World Health Organization. Maximum concentration of arsenic in water was found in Haldi village of Ballia (620.75 ppb). However, mean arsenic concentration in water followed the order: Karkatpur (257.21 ppb) < Haldi (310.15 ppb) < Sohaon (346.94 ppb) < Dharmarpur (401.75 ppb). In case of soil, maximum arsenic was detected in soil of Sohaon (15.43 ppm). Mean arsenic levels in soils followed the order: Karkatpur (9.24 ppm) < Haldi (9.82 ppm) < Dharmarpur (11.32 ppm) < Sohaon (14.08 ppm). Arsenic levels were higher in soils collected from 15–30 cm depth than 0–15 cm from the soil surface.  相似文献   

13.
In view of their sensitivity and importance, an ecological-economic analysis of wetlands has been carried out for various Indian states. Subsequently, the ecological wealths of different zones (north, south, east and west) have been computed and compared. Amongst states, Karnataka (7896.5 million US dollars yr(-1)), Gujarat (7689.4 million US dollars yr(-1)) and Andhra Pradesh (7670.9 million US dollars yr(-1)) are found to be the richest, whereas Nagaland (3.1 million US dollars yr(-1)), Meghalaya (5.9 million US dollars yr(-1)) and Sikkim (15.9 million US dollars yr(-1)) turn out to be the poorest. Amongst different zones, Southern Zone turns out to be the richest and the Northern Zone poorest. A ratio called ANR [Artificial (A) Wetland Wealth to Natural (N) Wetland Wealth Ratio (R)] has also been devised, which is the ratio of the ecological-economic values of artificial and natural wetlands. In other words, this ratio indicates the level of environmental concern of a given region. ANR ratio is found to be the highest for Madhya Pradesh (564.1) and Karnataka (159.8) states.  相似文献   

14.
Groundwater chemistry has been studied to examine the associated hydrogeochemical processes operating for the development of salinity in the groundwater in parts of Guntur district, Andhra Pradesh, India. The study area is underlain by charnockites and granitic gneisses associated with schists of the Precambrian Eastern Ghats. Groundwater is the main resource for irrigation besides drinking. Chemical parameters, pH, EC, TDS, Ca2+, Mg2+, Na+, K+, , , Cl, , , F and SiO2, are taken into account. Groundwater is of brackish type. Na+−Cl facies dominates the groundwater. Examination of compositional relations and mineral saturation states shows that the ion exchange of Ca2+ for adsorbed Na+, evapotranspiration, dissolution of soil salts, dissolution of NaCl and CaSO4, and precipitation of CaCO3 are the dominant hydrogeochemical processes associated with the groundwater composition in the area. Evapotranspiration causes accumulation of salts in the soil/weathered zone. These salts reach the water table by leaching through infiltrating recharge water. A positive relation between depth to water table and TDS with season supports this inference. The effects of human activities, such as intensive and long-term irrigation, irrigation-return-flow, application of unlimited agricultural fertilizers and recycling of saline groundwater, act to further increase the salinity in the groundwater. Therefore, the groundwater quality increases towards the flow path, while the post-monsoon groundwater shows higher concentrations of TDS, Na+, Mg2+, Cl, , , F and SiO2 ions. The study could help to understand the hydrogeochemical characteristics of the aquifer system for taking effective management measures to mitigate the inferior groundwater quality for sustainable development.  相似文献   

15.
通过实地调查与查阅资料相结合,发现雷公山国家级自然保护区共有33种外来入侵植物,隶属18科31属,以菊科(7种)最多。入侵等级以低等级为主,入侵生活型主要是多年生草本,原产地以尚不明确为主,引入途径以无意传播占绝对优势。外来入侵植物在雷公山国家级自然保护区不同功能区都有分布,但差异不明显,实验区有15种、缓冲区有14种、核心区有13种。在不同的植被类型(草坡、灌木林、乔木林)中分布差异明显,分别为20、14、10种。根据重要值和外来入侵植物危害等级计算得出危害系数,鬼针草Bidens pilosa (73. 71)、牛膝菊Galinsoga parviflora(55. 76)、白车轴草Trifolium repens(51. 17)较高,但目前,以上3种外来入侵植物在该保护区处于可控阶段,没有发生大规模的入侵。  相似文献   

16.
There is a growing concern over the potential accumulation of heavy metals in soils owing to rapid industrial and urban development and increasing reliance on agrochemicals in the last several decades. These metals can infiltrate through the soil thereby causing groundwater pollution. Surface soil samples (5 to 15 cm) collected from southeastern part of Ranga Reddy district were analyzed for 14 heavy metals (As, Ba, Co, Cr, Cu, Mo, Ni, Pb, Rb, Sr, V, Y, Zn and Zr) using Philips PW 2440 X-ray fluorescence spectrometer. Results for heavy and trace elements are reported for the first time in soils for this region. The contamination of the soils was assessed on the basis of enrichment factor (EF), geoaccumulation index (I (geo)), contamination factor and degree of contamination. The results reveal that variations in heavy element concentrations in the soil analyzed have both geogenic and anthropogenic contribution, due to the long period of constant human activities in the study area. The concentration of the metals Ba, Rb, Sr, V, Y and Zr were interpreted to be mainly inherited from parent materials (rocks) and the As, Co, Cr, Cu, Mo, Ni, Pb and Zn concentrations show contribution from geogenic and anthropogenic sources. The major element variations in soils are determined by the composition of the parent material predominantly involving granites.  相似文献   

17.
Termite mounds are abundant components of Tummalapalle area of uranium mineralization of Cuddapah District of Andhra Pradesh, India. The systematic research has been carried out on the application of termite mound sampling to mineral exploration in this region. The distribution of chemical elements Cu, Pb, Zn, Ni, Co, Cr, Li, Rb, Sr, Ba, and U were studied both in termite soils and adjacent surface soils. Uranium accumulations were noticed in seven termite mounds ranging from 10 to 36 ppm. A biogeochemical parameter called “Biological Absorption Coefficient” of the termite mounds indicated the termite affected soils contained huge amounts of chemical elements than the adjacent soils.  相似文献   

18.
The groundwater of Nalgonda district is well known for its very high fluoride content for the past five decades. Many researchers have contributed their scientific knowledge to unravel causes for fluoride enrichment of groundwater. In the present paper, an attempt has been made to relate the high fluoride content in the groundwater to hydrogeochemical characterization of the water in a fracture hard rock terrain—the Wailpally watershed. Groundwater samples collected from all the major geomorphic units in pre- and post-monsoon seasons were analyzed for its major ion constituents such as Ca2?+?, Mg2?+?, Na?+?, K?+?, CO $_{3}^{-}$ , HCO $_{3}^{-}$ , Cl???, SO $_{4}^{-2}$ , NO $_{3}^{-}$ , and F???. The groundwaters in the watershed have the average fluoride content of 2.79 mg/l in pre-monsoon and 2.83 mg/l in post-monsoon. Fluoride concentration in groundwater does not show perceptible change neither with time nor in space. The ionic dominance pattern is in the order of Na?+? > Ca2?+??> Mg2?+??> K??? among cations and HCO $_{3}^{-}\:\,>$ Cl????> SO $_{4}^{-2} >$ NO $_{3}^{-} >$ F??? among anions in pre-monsoon. In post-monsoon, Mg replaces Ca2?+? and NO $_{3}^{-}$ takes the place of SO $_{4}^{-2}$ . The Modified Piper diagram reflect that the water belong to Ca?+?2–Mg?+?2–HCO $_{3}^{-}$ to Na?+?–HCO $_{3}^{-}$ facies. Negative chloralkali indices in both the seasons prove that ion exchange between Na?+? and K?+? in aquatic solution took place with Ca?+?2 and Mg?+?2 of host rock. The interpretation of plots for different major ions and molar ratios suggest that weathering of silicate rocks and water–rock interaction is responsible for major ion chemistry of groundwater in Wailpally watershed. Chemical characteristics and evolution of this fluoride-contaminated groundwater is akin to normal waters of other hard rock terrain; hence, it can be concluded that aquifer material play an important role in the contribution of fluoride in to the accompanying water. High fluoride content in groundwater can be attributed to the continuous water–rock interaction during the process of percolation with fluorite-bearing country rocks under arid, low precipitation, and high evapotranspiration conditions.  相似文献   

19.
Most precious and world famed Himalayan rivers like Ganga, Yamuna, and their tributaries are originated from Uttarakhand state of India. Over the years, increased industrial activities and urban growth along the rivers and lakes have resulted in increased load over the water bodies. In the present study, a comparison of characteristics of water quality with respect to heavy metals (Fe, Zn, Cu, and Pb) and their interrelationships with some physiological parameters during different seasons of year 2010 has been made in the water bodies flowing through the two geographical regions, namely Garhwal and Kumaon regions of the Himalayan State of India. All observed values of Pb, 02 observation of the Cu, and 59 observations of Fe are found exceed with the WHO standard for drinking water; 83 observations of Pb, 110 observations of Cu, and 59 observations of Fe are found exceed with the Bureau of Indian Standards. However, none of the observation of Zn is found exceeding with the standard limit. Cu shows the highest concentration 7.30 mg/l among all observations and also its higher concentration in Kumaon rivers. All the metals show negative correlation with dissolved oxygen and pH. Fe in river Yamuna system and Zn in Kumaon rivers show significant temporal variations at 90 % level of significance (LOS). However, no significant temporal difference of remaining metals is observed even at 95 % LOS. All metals except Fe in river Yamuna system show very significant variation in spatial distribution in different river systems at 95 % LOS.  相似文献   

20.
Tea is the most commonly consumed beverage in the world. Tea infusion is prepared by pouring boiling hot water over cured leaves of the Camellia sinensis plant. Such a beverage should be free from toxic chemicals. Studies on the monitoring of pesticide residues in tea of South India had been carried. Tea samples collected from different districts of South India were analysed for the residues of certain pesticide such as dicofol, ethion, quinalphos, hexaconazole, fenpropathrin, fenvalerate and propargite. These pesticides are commonly used for the control of pests and diseases in tea. The results of study indicated that among 468 samples examined, only one sample contained hexaconazole residue that exceeded the maximum residue limit (MRL). Though the residues of ethion, quinalphos, hexaconazole, dicofol, propargite and fenpropathrin were most commonly found, only one sample exceeded the MRL.  相似文献   

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