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681.
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
682.
Transportation system has contributed significantly to the development of human civilization; on the other hand it has an
enormous impact on the ambient air quality in several ways. In this paper the air and noise pollution at selected sites along
three sections of National Highway was monitored. Pakistan National Highway Authority has started a Highway Improvement
program for rehabilitations and maintenance of National highways to improve the traffic flows, and would ultimately improve
the air quality along highways. The ambient air quality and noise level was monitored at nine different locations along these
sections of highways to quantify the air pollution. The duration of monitoring at individual location was 72 h. The most of
the sampling points were near the urban or village population, schools or hospitals, in order to quantify the air pollution
at most affected locations along these roads. A database consisting of information regarding the source of emission, local
metrology and air quality may be created to assess the profile of air quality in the area. 相似文献
683.
Mayack DT 《Environmental monitoring and assessment》2012,184(4):2497-2516
Many non-linear processes link atmospheric emissions to the bioavailability of metals; consequently, the monitoring of metals
in ecosystem components is required to model their ecodynamics. American mink (Neovison vison) and river otter (Lontra canadensis) have the potential to serve as an upper-level-consumer component in monitoring metals bioavailability. However, the relationship
of bioaccumulated metals to various environmental factors has not been explored nor have the effects of demographic factors
been resolved. To address these limitations, mink and otter, collected throughout New York State during 1998–2002, were analyzed
for hepatic concentrations of total mercury (Hg), cadmium (Cd), and lead (Pb). Relationships were investigated between metals
concentrations and landscape-level factors (physiographic zone, hydrologic unit, and elevation) and demographic factors (gender
and age). Considerable variation in Hg and Cd concentrations was observed relative to both physiographic zone and hydrologic
unit for both species. In contrast with Hg, Cd concentration increased predictably with increasing elevation. Mercury concentrations
were greater, but for Cd less, in otter than mink. Lead concentrations showed little landscape heterogeneity and were independent
of elevation. Age-related bioaccumulation was evident for Hg and Cd, but not for Pb, in both species. Mercury and Cd concentrations
were greater in female than male mink; however, Pb concentrations were greater in males than females. Inverse relationships
of relative growth (weight/length) to metals concentrations explained gender differences in Hg and Cd in mink. For otter,
no gender-related differences in metals concentrations were apparent. The suitability of mink and otter for monitoring programs
is discussed. 相似文献
684.
Alam R Munna G Chowdhury MA Sarkar MS Ahmed M Rahman MT Jesmin F Toimoor MA 《Environmental monitoring and assessment》2012,184(1):573-580
In rural areas in Bangladesh, groundwater is the principal source of water supply. This underground water is available in
considerable amount in shallow aquifers. It is free from pathogenic microorganisms and hence water-borne diseases. In plain
lands, other than hilly areas, water supply to 97% rural population comes from tube-wells, which is regarded to be a phenomenal
achievement in preserving public health. Besides, a dependable water supply system all throughout the country is offset by
two factors: (a) high salinity in surface plus groundwater in coastal areas; (b) want of suitable groundwater aquifers in
hilly areas and the high cost of setting up tube-wells due to deep underground water table and stony layers. However, presence
of arsenic in underground water now poses a serious threat to the success once made in water supply by setting up of manually
operated tube-wells in the village areas—the achievement is now on the brink of total collapse. In about 61 districts out
of 64, presence of arsenic exceeds a quantity of 0.05 mg/1, a permissible limit as per Bangladeshi water quality standard.
Harvesting rainwater can be a pragmatic solution to this problem, which is common in many places in Sylhet especially in the
hilly areas on the north eastern part of the city. This can be an alternative source of drinking water because of availability
of rainwater from March to October. Heavy rain occurs from end of May till mid September, which is commonly known as the rainy
season. This paper focuses on the possibility of harvesting rainwater in rural communities and thickly populated urban areas
of Sylhet. It also demonstrates the scopes of harvesting rainwater using simple and low-cost technology. With setting up of
a carefully planned rainwater storage tank, a family can have all of its drinking water from rain. Planned use of rainwater
through rainwater harvesting in the roof catchments may fulfill the entire annual domestic water demand of a family in the
rural areas of Bangladesh. 相似文献
685.
Brázová T Hanzelová V Miklisová D Salgovičová D Turčeková L 《Environmental monitoring and assessment》2012,184(11):6553-6561
The distribution and concentrations of polychlorinated biphenyls (PCBs) were determined in fish species (European perch Perca fluviatilis, northern pike Esox lucius, pike perch Sander lucioperca, wels catfish Silirus glanus, common carp Cyprinus carpio, European eel Anguilla anguilla, freshwater bream Abramis brama, goldfish Carassius auratus, and roach Rutilus rutilus) in a heavily polluted water reservoir Zemplínska ?írava (Slovakia). The study performed at two different time points 5?years apart (2004 and 2009) revealed serious PCB contamination of fish muscle tissue and significant interspecies as well as tissue-specific differences in PCB uptake by fish. Total PCBs broadly correlated with the trophic position of individual fish species within a food chain (P?0.01). The concentrations were particularly high in predatory fish species, perch, pike, and pike perch (108.0, 90.1, and 113.0?mg?kg(-1) lipid wt, respectively), but comparable PCB values were also found in non-predatory detrivorous freshwater bream (128.0?mg?kg(-1) lipid wt). The lowest PCB values were surprisingly assessed in European eel (17.1?mg?kg(-1) lipid wt). Tissue analysis showed the highest storage capacity of the liver (hepatopancreas in cyprinids) with maximum concentrations recorded found in northern pike (214.0?mg?kg(-1) lipid wt) and freshwater bream (163.0?mg?kg(-1) lipid wt). Negative correlations, mostly not significant, between the total PCB concentrations and fish weight were observed (P?>?0.05). The study has shown that the kind of fish, its feeding habit, and specific conditions of the habitat are mutually interrelated factors that are responsible for significant variations in fish body burdens. A tendency to PCB biomagnification was also proved in some fish species of this water reservoir. 相似文献
686.
Groundwater recharge and available groundwater resources in Chithar River basin, Tamil Nadu, India spread over an area of 1,722 km2 have been estimated by considering various hydrological, geological, and hydrogeological parameters, such as rainfall infiltration, drainage, geomorphic units, land use, rock types, depth of weathered and fractured zones, nature of soil, water level fluctuation, saturated thickness of aquifer, and groundwater abstraction. The digital ground elevation models indicate that the regional slope of the basin is towards east. The Proterozoic (Post-Archaean) basement of the study area consists of quartzite, calc-granulite, crystalline limestone, charnockite, and biotite gneiss with or without garnet. Three major soil types were identified namely, black cotton, deep red, and red sandy soils. The rainfall intensity gradually decreases from west to east. Groundwater occurs under water table conditions in the weathered zone and fluctuates between 0 and 25 m. The water table gains maximum during January after northeast monsoon and attains low during October. Groundwater abstraction for domestic/stock and irrigational needs in Chithar River basin has been estimated as 148.84 MCM (million m3). Groundwater recharge due to monsoon rainfall infiltration has been estimated as 170.05 MCM based on the water level rise during monsoon period. It is also estimated as 173.9 MCM using rainfall infiltration factor. An amount of 53.8 MCM of water is contributed to groundwater from surface water bodies. Recharge of groundwater due to return flow from irrigation has been computed as 147.6 MCM. The static groundwater reserve in Chithar River basin is estimated as 466.66 MCM and the dynamic reserve is about 187.7 MCM. In the present scenario, the aquifer is under safe condition for extraction of groundwater for domestic and irrigation purposes. If the existing water bodies are maintained properly, the extraction rate can be increased in future about 10 % to 15 %. 相似文献
687.
Azadeh Taghinia Hejabi H. T. Basavarajappa 《Environmental monitoring and assessment》2013,185(2):1273-1283
Cu, Cr, Fe, Mn, Ni, Pb, and Zn in the sediments of the Kabini River, Karnataka, India was studied to determine the association of metal with various geochemical phases by sequential extraction. The variations of heavy metal concentration depend on the lithology of the river basin and partly on anthropogenic activities. The Kabini River sediments are dominated by Sargur supracrustals with amphibolites, gneisses, carbonates, and ultrabasic rocks weathering into gneissic and serpentine soils carrying a natural load of cationic heavy metals. The source of heavy metals in the Kabini riverbed sediments is normally envisaged as additional inputs from anthropogenic over and above natural and lithogenic sources. Geochemical study indicates the metals under study were present mostly in the least mobilizable fraction in the overlying water and it is concluded that heavy metals in these sediments are to a great extent derived from multisource anthropogenic inputs besides geochemical background contributions The results show that lead and chromium have higher potential for mobilization from the sediment due to higher concentration at the exchangeable ion and sulfide ion bounded, also Cu and Pb have the greatest percentage of carbonate fraction, it means that the study area received inputs from urban and industrial effluents. Association of the Fe with organic matter fraction can be explained by the high affinity of these elements for the humic substances. Further, Zn and Ni reveal a significant enrichment in sediment and it is due to release of industrial wastewater into the river. These trace metals are possible contaminants to enter into aquatic and food chain. 相似文献
688.
T. R. Gireeshkumar P. M. Deepulal N. Chandramohanakumar 《Environmental monitoring and assessment》2013,185(3):2535-2552
Sequential chemical extraction using chelating agents were used to study the P dynamics and its bioavailability along the surface sediments of the Cochin estuary (southwest coast of India). Sediments were analyzed for major P species (iron bound P, calcium bound P, acid soluble organic P, alkali soluble organic P and residual organic P), Fe, Ca, total carbon, organic carbon, total nitrogen and total sulfur contents. An abrupt increase in the concentration of dissolved inorganic P with increasing salinity was observed in the study region. Iron-bound P exhibited a distinct seasonal pattern with maximum values in the monsoon season when fresh water condition was prevailed in the estuary. As salinity increased, the percentage of iron-bound P decreased, while that of calcium-bound P and total sedimentary sulfur increased. C/P and N/P ratios were low which indicate that large amounts of organic matter enriched with P tend to accumulate in surface sediments. The high organic P contribution in the sedimentary P pool may indicate high organic matter load with incomplete mineralization, as well as comparatively greater percentage of humic substance and resistant organic compounds. Principal component analysis is employed to find the possible processes influencing the speciation of P in the study region and indicate the following processes: (1) the spatial and seasonal variations of calcium bound P and acid soluble organic P was mainly controlled by sediment texture and organic carbon content, (2) sediment redox conditions control the distribution of iron bound P and (3) the terrigenous input of organic P is a significant processes controlling total P content in surface sediments. The bioavailable P was very high in the surface sediments which on an average accounts for 59 % in the pre-monsoon, 65 % in the monsoon and 53 % in the post-monsoon seasons. The surface sediments act as a potential internal source of P in the Cochin estuary. 相似文献
689.
A. O. Oyeyiola C. M. Davidson K. O. Olayinka T. O. Oluseyi B. I. Alo 《Environmental monitoring and assessment》2013,185(3):2167-2177
Surface sediments collected from the Lagos Lagoon, Nigeria, and three adjoining rivers were analysed for their physicochemical properties and pseudo-total concentration of the potentially toxic metals (PTM) Cd, Cr, Cu, Pb and Zn. The concentration of the PTM varied seasonally and spatially. Odo-Iyaalaro was observed to be the most polluted river, with highest concentrations of 42.1 mg kg?1, 102 mg kg?1, 185 mg kg?1, 154 mg kg?1 and 1040 mg kg?1 of Cd, Cr, Cu, Pb and Zn, respectively, while Ibeshe River was the least contaminated, apart from a site affected by Cu from the textile industry. Some of the sediments were found to be above the consensus-based probable effect concentrations and Dutch sediment guideline for metals. Overall metal concentrations were similar to those reported for other tropical lagoon and estuarine systems affected by anthropogenic inputs as a result of rapid urbanisation. Due to the large number of samples, principal component analysis was used to examine relationships within the data set. Generally, sediments collected during the dry season were observed to have higher concentration of PTM than those collected during the rainy season. This means that PTM could accumulate over a prolonged period and then be released relatively rapidly, on an annual basis, into tropical lagoon systems. 相似文献
690.
The LUCAS topsoil database and derived information on the regional variability of cropland topsoil properties in the European Union 总被引:2,自引:0,他引:2
Gergely Tóth Arwyn Jones Luca Montanarella 《Environmental monitoring and assessment》2013,185(9):7409-7425
Approximately 20,000 topsoil samples were collected in 25 European Union (EU) Member States (EU-27 except Bulgaria and Romania) with the aim to produce the first coherent pan-European physical and chemical topsoil database, which can serve as baseline information for an EU wide harmonized soil monitoring. The soil sampling was undertaken within the frame of the Land Use/Land Cover Area Frame Survey (LUCAS), a project to monitor changes in the management and character of the land surface of the EU. Soil samples have been analysed for basic soil properties, including particle size distribution, pH, organic carbon, carbonates, NPK, cation exchange capacity (CEC) and multispectral signatures. Preliminary studies show the outstanding potential of the dataset for enhancing the knowledge base on soils in the EU. The current paper provides an introduction to the LUCAS Topsoil 2009 project and provides an example of data applicability for cropland assessment by highlighting initial results for regional and national comparisons. 相似文献