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931.
Seasonal variations of heavy metal contamination in river Gomti of Lucknow city region 总被引:2,自引:0,他引:2
Lohani MB Singh A Rupainwar DC Dhar DN 《Environmental monitoring and assessment》2008,147(1-3):253-263
The present study deals with the seasonal variations in the concentrations of heavy metals namely chromium, lead and mercury by using spectrophotometric methods. The water samples were collected at regular intervals from five selected sites of river Gomti in the pre-monsoon period (months of February-May) and the post monsoon period (months of October-January). The concentrations of chromium (VI) and mercury (II) were determined by using Genesys-10 UV-VIS Spectrophotometer while lead (II) concentrations were determined using Atomic Absorption Spectrophotometer, Perkin-Elmer 5000 model. The concentrations of all the three metals were found to be higher in the pre-monsoon period than in the post-monsoon period. The statistical analysis of the data was discussed in both the seasons in terms of mean, standard deviation and coefficient of variation. 相似文献
932.
Suitability assessment of groundwater for drinking, irrigation and industrial use in some North Indian villages 总被引:3,自引:0,他引:3
Haritash AK Kaushik CP Kaushik A Kansal A Yadav AK 《Environmental monitoring and assessment》2008,145(1-3):397-406
The study comprised suitability assessment of groundwater for drinking, irrigation, and industrial use. A total of 34 groundwater samples were collected from Rewari town and its perimeter from the land chiefly used for agriculture. Physico-chemical characterization of the samples revealed that groundwater from most of the sources was not fit for drinking owing to a high concentration of calcium, magnesium, hardness and fluoride. Suitability for irrigation, too, was low since most of the sources had high value of sodium adsorption ratio (SAR), residual sodium carbonate (RSC), soluble sodium percentage (SSP) and magnesium hazard which can render salinity and alkali hazard to soils on long term use in irrigation. No source of water was found to be suitable for industrial application since it had high concentration of calcium carbonate which can precipitate very easily. It was observed that sodium, sulphate, and chloride were the chief ions present in water and based on the abundance of ions and their correlation type, most of the groundwater samples are of sodium sulphate and/or sodium chloride type. The high concentration of the chemical constituents is attributed to the lithologic composition of the area. It was observed that the water of deep meteoric percolation type was of sodium sulphate type and the shallow of sodium chloride type. 相似文献
933.
Selvi VA Prajapati N Masto RE Ram LC Banerjee R Srivastava NK 《Environmental monitoring and assessment》2008,145(1-3):251-256
Enormous quantity of water is used for coal beneficiation and accordingly huge amount of effluents are being generated. In this study an attempt was made to evaluate the potential of this effluent water for irrigation. Water samples were collected from three different points (a) feeding point, (b) thickening point, and (c) outlet point of coal washery, and from Damodar River for monitoring the water quality. The samples were analyzed for various parameters and compared with prescribed standard, which revealed that the total suspended solids of thickening point and Damodar River were higher. A pot experiment with maize was conducted to study the suitability of this coal washery water for irrigation. Pots were irrigated with water from the three points of washery and Damodar River in two concentrations (100% and 50% dilution with distilled water); pure distilled water was used for control. There was 100% germination in all the treatments. The plant growth, chlorophyll content and soil quality parameters were significantly better in washery and Damodar River water treated pots. The Damodar River water and washery water from feeding and outlet point could be successfully used for irrigation. In general mixing with good quality water has shown better results. 相似文献
934.
Singh R Singh AP Singh MP Kumar A Varshney CK 《Environmental monitoring and assessment》2008,144(1-3):43-51
Isoprene is most dominant volatile organic compounds (VOC) emitted by many plants. In this study 40 common Indian plant species were examined for isoprene emission using dynamic flow through enclosure chamber technique. Isoprene emission rates of plants species were found to vary from undetectable to 69.5 microg g(-1) h(-1) (Madhuca latifolia). Besides, an attempt has been made to evaluate suitability of 80 common Indian plant species for planting programmes. Out of 80 species, 29 species were moderate to high emitters (10 to < or =25 microg g(-1) h(-1)), 12 species were low emitter emitters (1 to < or =10 microg g(-1) h(-1)) and remaining 39 species were found to be negligible or non emitters (<1 microg g(-1) h(-1)) of isoprene. About 50% plant species selected for planting programmes in India were found to be moderate to high emitters of isoprene. 相似文献
935.
Foran J. Brosnan T. Connor M. Delfino J. DePinto J. Dickson K. Humphrey H. Novotny V. Smith R. Sobsey M. Stehman S. 《Environmental monitoring and assessment》2000,62(2):147-167
The International Life SciencesInstitute (ILSI) Risk Science Institute (RSI) convenedan expert panel of scientists to developrecommendations for a comprehensive monitoring programfor the Croton and Catskill/Delaware watersheds, whichprovide drinking water to New York City's residents. This effort was conducted as part of efforts topreserve and enhance the quality of New York City'sreservoir system through a watershed protectionprogram. The panel developed recommendations for astrategic framework on which to construct a monitoringprogram. As part of this activity, the paneldetermined whether existing monitoring activities weredeficient and, where activities were deficient, thepanel developed recommendations for additionalinformation that should be collected.The panel recommended the development and use of anintegrated approach to watershed monitoring, whichdraws on modeling, risk-based planning and analysis,statistical sampling and design, and basic compliancemonitoring. The approach should be designed toprovide an assessment of natural and anthropogenicsources of stress to the system as well as anassessment of water quality trends in response tostresses acting in concert, both over the long termand over the five-year New York City Memorandum ofAgreement (MOA) assessment time frame. It should alsoprovide an assessment of the human health andenvironmental risks posed by a variety of stressors,and the impact of management actions implemented toameliorate stressors. 相似文献
936.
K. Bruce Jones Anne C. Neale Maliha S. Nash Kurt H. Riitters James D. Wickham Robert V. O'Neill Rick D. van Remortel 《Environmental monitoring and assessment》2000,63(1):159-174
Using a new set of landscape indicator data generated by the U.S.EPA, and a comprehensive breeding bird database from the National Breeding Bird Survey, we evaluated associations between breeding bird richness and landscape characteristics across the entire mid-Atlantic region of the United States. We evaluated how these relationships varied among different groupings (guilds) of birds based on functional, structural, and compositional aspects of individual species demographics. Forest edge was by far the most important landscape attribute affecting the richness of the lumped specialist and generalist guilds; specialist species richness was negatively associated with forest edge and generalist richness was positively associated with forest edge. Landscape variables (indicators) explained a greater proportion of specialist species richness than the generalist guild (46% and 31%, respectively). The lower value in generalists may reflect finer-scale distributions of open habitat that go undetected by the Landsat satellite, open habitats created by roads (the areas from which breeding bird data are obtained), and the lumping of a wide variety of species into the generalist category. A further breakdown of species into 16 guilds showed considerable variation in the response of breeding birds to landscape conditions; forest obligate species had the strongest association with landscape indicators measured in this study (55% of the total variation explained) and forest generalists and open ground nesters the lowest (17% of the total variation explained). The variable response of guild species richness to landscape pattern suggests that one must consider species' demographics when assessing the consequences of landscape change on breeding birds. 相似文献
937.
938.
The Vegetation of Wet Meadows in Relation to Their Land-use 总被引:5,自引:0,他引:5
Susan M. Galatowitsch Diane C. Whited Richard Lehtinen Jason Husveth Karen Schik 《Environmental monitoring and assessment》2000,60(2):121-144
Wetland biomonitoring approaches are needed to determine when changes in response to stressors are occurring and to predict the consequences of proposed land-use changes. These approaches require an understanding of shifts in biota that occur in response to land-use, data that are lacking for most kinds of wetlands. Changes in floristic composition corresponding to land-use differences at multiple scales (site to 2500 m radius) were characterized for 40 wet meadows associated with prairie glacial marshes in Minnesota (U.S.A.). In general, guild was more useful than species composition for indicating land-use impacts. Site impacts (stormwater, cultivation) and landscape disturbance (agriculture and urbanization, combined), coincide with a reduction in native graminoid and herbaceous perennial abundance (e.g., Carex lasiocarpa, Calamagrostis canadensis, Spartina pectinata). This vegetation is replaced with annuals (e.g, Bidens cernua, Polygonum pensylvanicum) in recently cultivated sites or introduced perennials (e.g., Phalaris arundinacea, Typha angustifolia) and floating aquatics (lemnids) in stormwater impacted wetlands. Ditches also reduce native perennial importance and increase perennials, but only when they are in highly impacted landscapes. 相似文献
939.
Balachandran KK Jayalakshmy KV Laluraj CM Nair M Joseph T Sheeba P 《Environmental monitoring and assessment》2008,139(1-3):217-226
The interaction effects of abiotic processes in the production of phytoplankton in a coastal marine region off Cochin are
evaluated using multiple regression models. The study shows that chlorophyll production is not limited by nutrients, but their
physiological regulations (responses to nutrients, pH, temperature and salinity) are mainly responsible for the increased
biological production. The model explaining 77% of variability for chlorophyll a production is indicative of preconditioning of the coastal waters. The phytoplankton production is found to be sensitive
to the environment, which varies seasonally. Further, the study suggests that supply of organic matter and grazing of zooplankton
(not included) would improve the model efficiency. Despite this, the good agreement in the computed and measured chlorophyll
a values shows that step-up multiple regression model is a useful tool to understand the influence of environmental variables
on the production of phytoplankton in these coastal waters. 相似文献
940.