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591.
Impact of intensive agricultural practices on drinking water quality in the EVROS Region (NE GREECE) by GIS analysis 总被引:1,自引:0,他引:1
Chemical fertilizers are used extensively in modern agriculture, in order to improve yield and productivity of agricultural products. However, nutrient leaching from agricultural soil into groundwater resources poses a major environmental and public health concern. The Evros region is one of the largest agricultural areas in Northern Greece, extending over 1.5 million acres of cultivated land. Many of its drinking water resources are of groundwater origin and lie within agricultural areas. In order to assess the impact of agricultural fertilizers on drinking water quality in this region, tap-water samples from 64 different locations were collected and analyzed for the presence of nitrates [Formula: see text], nitrites [Formula: see text], ammonium [Formula: see text], sulfate [Formula: see text] and phosphate [Formula: see text]. These chemicals were selected based on the information that ammonium nitrate, ammonium sulfate and inorganic phosphate were the primary fertilizers used in local crop production. [Formula: see text], [Formula: see text] and [Formula: see text] levels exceeding accepted values were recorded in 6.25, 4.70 and 9.38% of all sampling points, respectively. [Formula: see text] and [Formula: see text] concentrations, on the other hand, were inside the permitted range. The data generated were introduced into a geographic information system (GIS) program for computer analysis and projection maps representing afflicted areas were created. Our results indicate a profound geographic correlation in the surface distribution of primary contaminants in areas of intensified agricultural production. Thus, drinking water pollution in these areas can be attributed to excessive fertilizer use from agricultural sources. 相似文献
592.
Plaisance H Desmettres P Leonardis T Pennequin-Cardinal A Locoge N Galloo JC 《Journal of environmental monitoring : JEM》2008,10(4):517-526
This study examined the performances of a thermal desorbable radial diffusive sampler for the weekly measurement of eight glycol ethers in indoor air and described the results of an application of this method carried out as part of HABIT'AIR Nord - Pas de Calais program for the air monitoring of these compounds in sixty homes located in northern France. The target compounds were the four glycol ethers banned from sale to the public in France since the 1990s (i.e. 2-methoxy ethanol, 2-ethoxy ethanol and their acetates) and four other glycol ethers derivatives of which the use have increased considerably (i.e. 1-methoxy-2-propanol, 2-butoxy ethanol and their acetates).A test program was carried out with the aim of validating the passive sampling method. It allowed the estimation of all the parameters of a method for each compound (calibration, analytical precision, desorption efficiency, sampling rate in standard conditions, detection limit and stability of sample before and after exposure), the examination of the influence of environmental factors on the sampling rate by some exposure chamber experiments and the assessment of the uncertainty of the measurements.The results of this evaluation demonstrated that the method has turned out to be suitable for six out of eight glycol ethers tested. The effect of the environmental factors on the sampling rates was the main source of measurement uncertainty. The measurements done in sixty homes revealed a relative abundance of 1-methoxy-2-propanol that was found in more than two thirds of homes at concentration levels of 4.5 microg m(-3) on average (a maximum value of 28 microg m(-3)). 1-methoxy-2-propanol acetate and 2-butoxy ethanol were also detected, but less frequently (in 19% of homes) and with the concentrations below 12 microg m(-3). The highest levels of these glycol ethers appear to be in relation to the emissions occurring at the time of cleaning tasks. 相似文献
593.
Rutter AP Schauer JJ Lough GC Snyder DC Kolb CJ Von Klooster S Rudolf T Manolopoulos H Olson ML 《Journal of environmental monitoring : JEM》2008,10(1):102-108
Gaseous elemental mercury (GEM), particulate mercury (PHg) and reactive gaseous mercury (RGM) were measured every other hour at a rural location in south central Wisconsin (Devil's Lake State Park, WI, USA) between April 2003 and March 2004, and at a predominantly downwind urban site in southeastern Wisconsin (Milwaukee, WI, USA) between June 2004 and May 2005. Annual averages of GEM, PHg, and RGM at the urban site were statistically higher than those measured at the rural site. Pollution roses of GEM and reactive mercury (RM; sum of PHg and RGM) at the rural and urban sites revealed the influences of point source emissions in surrounding counties that were consistent with the US EPA 1999 National Emission Inventory and the 2003-2005 US EPA Toxics Release Inventory. Source-receptor relationships at both sites were studied by quantifying the impacts of point sources on mercury concentrations. Time series of GEM, PHg, and RGM concentrations were sorted into two categories; time periods dominated by impacts from point sources, and time periods dominated by mercury from non-point sources. The analysis revealed average point source contributions to GEM, PHg, and RGM concentration measurements to be significant over the year long studies. At the rural site, contributions to annual average concentrations were: GEM (2%; 0.04 ng m(-3)); and, RM (48%; 5.7 pg m(-3)). At the urban site, contributions to annual average concentrations were: GEM (33%; 0.81 ng m(-3)); and, RM (64%; 13.8 pg m(-3)). 相似文献
594.
Tucker SP 《Journal of environmental monitoring : JEM》2008,10(11):1337-1349
Three sampling and analytical methods have been developed and evaluated for ortho-phthalaldehyde (OPA): (1) an HPLC-UV method for OPA in air, (2) a fluorimetric method for OPA on surfaces, and (3) a colorimetric method for OPA on surfaces. (1) The air sampler contains 350 mg of silica gel coated with 1 mg of acidified 2,4-dinitrophenylhydrazine (DNPH). Air sampling may be conducted at 0.03 to 1.0 L min(-1) for periods up to 8 h. Samples were eluted with ethyl acetate, and the eluents were allowed to stand for 72 h. Analysis was by high performance liquid chromatography (HPLC) with a UV detector set at 369 nm. An unusual phenomenon was the observation that the stability of the sample on a sampler at 3 degrees C tends to decrease as the total quantity of OPA collected on the sampler decreases. Elution of the samples within 24 h of air sampling is required. The detection limit (LOD) is approximately 0.02 microg of OPA per sample. OPA on surfaces may be collected with strips cut from a sheet of polyvinyl alcohol (PVA wipe). (2) In the surface wipe method with analysis by fluorescence measurement, the strips of PVA wipe were placed into dimethyl sulfoxide. An aliquot was treated with aqueous N-acetyl-l-cysteine and ethylenediamine. Analysis was performed with a portable fluorometer (excitation and emission wavelengths = 365 nm and 438 nm, respectively). The LOD is 0.2 microg per sample. (3) In the surface wipe method with visual colorimetric detection, the strips of PVA wipe were placed into 30 : 70 acetonitrile : water. An aliquot was treated with N-(1-naphthyl)ethylenediamine in 0.1 m sulfuric acid. After color development, the LOD is approximately 48 microg per sample. These methods have been field tested in a hospital. 相似文献
595.
Laluraj CM Krishnan KP Thamban M Mohan R Naik SS D'Souza W Ravindra R Chaturvedi A 《Environmental monitoring and assessment》2009,149(1-4):377-383
The scanning electron microscopy-energy dispersive spectroscopic (SEM-EDS) study of selected samples from an ice core collected from Central Dronning Maud Land (CDML), East Antarctica, revealed several microparticles. They are mainly siliceous and carbonaceous particles and have distinct variations in their shape and composition. The morphology and major element chemistry of the particles suggest their origin from either volcanic eruptions or continental dust. The EDS analysis revealed that the volcanic particles are enriched in silica (average SiO2 62%), compared to the continental dust particle (average SiO2 56%). We found that the tephra relating to Agung (1963) and Karkatau (1883) volcanic eruptions, as recorded, in the ice core harbored microbial cells (both coocoid and rods). The occurrence of organic and inorganic particles which bear relation to volcanic eruption and continental dust implies significant environmental changes in the recent past. 相似文献
596.
Nagaraj P Aradhana N Shivakumar A Shrestha AK Gowda AK 《Environmental monitoring and assessment》2009,157(1-4):575-582
A simple and sensitive spectrophotometric method for the determination of chromium has been developed. The method is based on the diazotization of Dapsone in hydroxylamine hydrochloride medium and coupling with N-(1-Napthyl) Ethylene Diamine Dihydrochloride by electrophilic substitution to produce an intense pink azo-dye, which has absorption maximum at 540 nm. The Beer's law is obeyed from 0.02-1.0 microg mL(-1) and the molar absorptivity is 3.4854 L mol(-1) cm(-1). The Limits of quantification and Limit of detection of the proposed method are 0.0012 microg mL(-1) and 0.0039 microg mL(-1) respectively. The method has been successfully applied for the determination of chromium in water samples and the results were statistically evaluated with that of the reference method. 相似文献
597.
Volatile organic compounds (VOCs) analysis was carried out for the surface water of the Savitri river during the period of June 2005 to June 2007. BTEX compounds (Benzene, Toluene, Xylene & Ethyl benzene) were analyzed by using micro extraction technique (Purge & Trap). Concentrations of these BTEX compounds were ranging from 0.1 to 1.5 ppm during sampling period. Higher concentrations of BTEX were found at sampling location VI. Concentration of ethyl benzene was very low as compare to other compounds. However, the concentration of benzene was very high. Seasonal variations in conc. of BTEX compounds were observed and higher concentration was detected during the summer season. Salting-out effect had given higher quantification values. In PCA and PFA, the component loading for all the variables are positively correlated. Death of fishes was observed in the river that is indication of severe pollution problem. 相似文献
598.
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
599.
Deforestation is recognized as one of the most significant component in LULC and global changes scenario. It is imperative to assess its trend and the rates at which it is occurring. The changes will have long-lasting impact on regional climate and in turn on biodiversity. In North-East India, one of the recognized global biodiversity hotspots, approximately 30% of total forest cover is under pressure of rapid land use changes. This region harbors variety of rare and endemic species of flora and fauna. It also has a strong bearing on regional climatic conditions. Extensive shifting cultivation, compounded by increasing population pressure and demands for agriculture land are the prime drivers in addition to other proximate drivers of deforestation. It is therefore of prime concern to analyse forest cover changes in the region, assess rate of change and extent and to identify the areas, which show repetitive changes. We analyzed forest cover maps from six temporal datasets based on satellite data interpretation, converted to geospatial database since 1972 till 1999. The states of Meghalaya, Nagaland and Tripura show highest changes in forest cover. Arunachal Pradesh shows least dynamic areas and maintains a good forest cover owing to its topographical inaccessibility in some areas. The present study reports the forest cover changes in the region using geospatial analysis and analyse them to devise proper management strategies. 相似文献
600.
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