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11.
Assessment of the impact of landfill on groundwater quality: A case study of the Pirana site in western India 总被引:1,自引:0,他引:1
Singh UK Kumar M Chauhan R Jha PK Ramanathan A Subramanian V 《Environmental monitoring and assessment》2008,141(1-3):309-321
In present study focus has been given on estimating quality and toxicity of waste with respect to heavy metals and its impact
on groundwater quality, using statistical and empirical relationships between different hydrochemical data, so that easy monitoring
may be possible which in turn help the sustainable management of landfill site and municipal solid waste. Samples of solid
waste, leachate and groundwater were analyzed to evaluate the impact of leachates on groundwater through the comparison of
their hydrochemical nature. Results suggest the existence of an empirical relationship between some specific indicator parameters
like heavy metals of all three above mentioned sample type. Further, K/Mg ratio also indicates three groundwater samples heavily
impacted from leachate contamination. A good number of samples are also showing higher values for and Pb than that of World Health Organization (WHO) drinking water regulation. Predominance of Fe and Zn in both groundwater
and solid waste samples may be due to metal plating industries in the area. Factor analysis is used as a tool to explain observed
relation between numerous variables in term of simpler relation, which may help to deduce the strength of relation. Positive
loading of most of the factors for heavy metal clearly shows landfill impact on ground water quality especially along the
hydraulic gradient. Cluster analysis, further substantiates the impact of landfill. Two major groups of samples obtained from
cluster analysis suggest that one group comprises samples that are severely under the influence of landfill and contaminated
leachates along the groundwater flow direction while other assorted with samples without having such influence. 相似文献
12.
Correspondence between spatial patterns in fish assemblages in ohio streams and aquatic ecoregions 总被引:5,自引:0,他引:5
David P. Larsen James M. Omernik Robert M. Hughes Christina M. Rohm Thomas R. Whittier Andrew J. Kinney Alisa L. Gallant Daniel R. Dudley 《Environmental management》1986,10(6):815-828
Land classification systems can be useful for assessing aquatic ecosystems if relationships among them exist. Because the character of an aquatic ecosystem depends to a large extent upon the character of the landscape it drains, spatial patterns in aquatic ecosystems should correspond to patterns in the landscape. To test this hypothesis, the US state of Ohio was divided into four aquatic ecoregions based on an analysis of spatial patterns in the combination of land-surface form, land use, potential natural vegetation, and soil parent material. During the period July–October 1983, fish assemblages were sampled in 46 streams that were representative of the ecoregions, and that had watersheds relatively undisturbed by human activities. Spatial patterns of the fish assemblages were examined relative to the ecoregions; distinct regional differences were identified. The assemblages differed most between the Huron/Erie Lake Plain region and the Western Allegheny Plateau region; assemblages in the Eastern Corn Belt Plains and the Erie/Ontario Lake Plain-Interior Plateau regions were intermediate. This pattern also reflects the gradient in landscape character as one moves from the northwest to the southeast of Ohio. 相似文献
13.
María J. Darias Harry M. Murray Jeffrey W. Gallant Susan E. Douglas Manuel Yúfera Gonzalo Martínez-Rodríguez 《Marine Biology》2007,152(1):109-118
A restoration programme was introduced in the Mondego Estuary (Portugal) to recover seagrass beds of Zostera noltii endangered by eutrophication. A long-term survey of 10 years was used to assess the development of the processes involved,
focusing one of the key species (Cyathura carinata, Isopoda). The mitigation measures implemented since 1998 (nutrient loading reduction, freshwater circulation improvement
and seagrass bed protection) enhanced water quality and seagrass recovery, thus preventing the development of macroalgal blooms.
C. carinata was resilient to the occurrence of floods and macroalgal blooms, although both events caused dispersion of individuals. This
isopod was not much influenced by the changes occurring in the estuary, showing an unalterable population structure during
the entire study period. After 1998, its density and biomass became more stable at an inner unvegetated sand flat area, where
this isopod was most abundant; its population slightly increased in a bare mud flat at the middle section of the estuary;
but it could not establish successfully in a downstream Z. noltii bed, contrarily to other common estuarine species. Apart from other unknown reasons, the disrupted balanced between trematodes
and their hosts, caused by the eutrophication processes, may have an important role in the discontinuity of C. carinata at the Z. noltii bed. If the intertidal areas become fully restored to the original seagrass coverage, high prevalence and intensity trematodes
may prevent this isopod and other crustaceans from recovering within the intervened areas, by enhancing host mortality and
recruitment failure. In order to avoid this kind of situation, it may be necessary to survey the levels of parasite infestation
within the target hosts and safeguard areas where crustaceans present healthy populations. 相似文献
14.
AL Heffernan K English LML Toms AM Calafat L Valentin-Blasini P Hobson S Broomhall RS Ware P Jagals PD Sly JF Mueller 《Environmental science and pollution research international》2016,23(23):23436-23448
A range of pesticides are available in Australia for use in agricultural and domestic settings to control pests, including organophosphate and pyrethroid insecticides, herbicides, and insect repellents, such as N,N-diethyl-meta-toluamide (DEET). The aim of this study was to provide a cost-effective preliminary assessment of background exposure to a range of pesticides among a convenience sample of Australian residents. De-identified urine specimens stratified by age and sex were obtained from a community-based pathology laboratory and pooled (n = 24 pools of 100 specimens). Concentrations of urinary pesticide biomarkers were quantified using solid-phase extraction coupled with isotope dilution high-performance liquid chromatography–tandem mass spectrometry. Geometric mean biomarker concentrations ranged from <0.1 to 36.8 ng/mL for organophosphate insecticides, <0.1 to 5.5 ng/mL for pyrethroid insecticides, and <0.1 to 8.51 ng/mL for all other biomarkers with the exception of the DEET metabolite 3-diethylcarbamoyl benzoic acid (4.23 to 850 ng/mL). We observed no association between age and concentration for most biomarkers measured but noted a “U-shaped” trend for five organophosphate metabolites, with the highest concentrations observed in the youngest and oldest age strata, perhaps related to age-specific differences in behavior or physiology. The fact that concentrations of specific and non-specific metabolites of the organophosphate insecticide chlorpyrifos were higher than reported in USA and Canada may relate to differences in registered applications among countries. Additional biomonitoring programs of the general population and focusing on vulnerable populations would improve the exposure assessment and the monitoring of temporal exposure trends as usage patterns of pesticide products in Australia change over time. 相似文献
15.
Two honey samples are taken from two parts of the same honeycomb: one that contacts to the surface of the wire and the other
taken from the surface that does not contact the wires. Heavy metal contents of these two samples were determined by inductively
coupled plasma atomic emission spectrometry). The Mo, Cd, Cr, Fe, Mn, Ni and Zn contents of the honey in contact with wire
is higher when compared to the other. Especially, Fe and Zn contents of honey in contact with wire is much higher than the
non-contact one. These values are, respectively, 190.21 and 112.76 ppm. Besides, Ni content of honey in contact with wire
is approximately 50% higher. 相似文献
16.
Persistence,variance and toxic levels of organochlorine pesticides in fluvial sediments and the role of black carbon in their retention 总被引:1,自引:0,他引:1
Musarrat Parween AL. Ramanathan P. S. Khillare N. J. Raju 《Environmental science and pollution research international》2014,21(10):6525-6546
The present study assesses the persistence and variation of organochlorine pesticides (OCPs) and their regulation by total organic carbon (TOC) and black carbon (BC) in freshwater sediment. Sediment samples from the Yamuna River, a major tributary of the Ganges (one of the most populated and intensively used rivers in Asia), had high levels of Σ20OCPs (21.41 to 139.95 ng g?1). β-Hexachlorocyclohexane (β-HCH) was the most predominant component. ΣHCH and Σdichloro-diphenyl-trichloroethane (DDT) constituted ~86 % of Σ20OCPs. Isomer ratios indicated fresh usage of lindane, DDT and technical-grade HCH. Toxicological comparison with freshwater sediment quality guidelines showed γ-HCH and DDT at high levels of concern. β-HCH, α-HCH, endrin, heptachlor epoxide, dichloro-diphenyl-dichloroethane (DDD), dichloro-diphenyl-dichloroethylene and chlordane were above some of the guideline levels. TOC and BC had mean concentrations of 1.37?±?0.51 % and 0.46?±?0.23 mg g?1, respectively. BC constituted 1.25 to 10.56 % of TOC. We observed low to moderate correlations of BC with isomers of HCH, p,p′-DDT and methoxychlor while of TOC with Σ20OCPs, γ-HCH, endosulfan sulfate and methoxychlor. Principal component analysis enabled correlating and clustering of various OCPs, BC and TOC. OCP distribution was related with pH, electrical conductivity, soil moisture and finer fractions of sediment. OCPs with similarity in properties that determine their interactions with carbonaceous components of sediment clustered together. A number of factors may, thus, be involved in the regulation of interactive forces between BC and OCPs. BC in this study may be more important than TOC in the retention of some OCPs into fluvial sediments, thereby reducing their bioavailability. The finding is probably the first of its kind to report and emphasises the role of BC in the persistence of OCPs in fluvial sediments. 相似文献
17.
Fahad AL Juhaimi Kashif Ghafoor Mehmet Musa Özcan 《Environmental monitoring and assessment》2014,186(4):2165-2170
The date (Phoenix dactylifera L.) fruits (Soukari, Soulag, Barhi, Khulas, Rozaiz, Soughi and Monaif) were evaluated with respect to some physical and chemical properties. While crude protein contents of fruits change between 1.51 % (Soulag) to 2.41 % (Soughi), crude fibre contents ranged between 1.91 % (Soukari) to 3.90 % (Barhi). Vitamin C contents of date samples changed between 971.82 mg/kg (Soughi) to 1,453.15 mg/kg (Barhi). Antioxidant activity of date fruits ranged from 80.07 IC50 (Soukari) to 81.21 IC50 (Soulag). The highest phenolic content was found in Khulas with a mean value of 198 mg GAE/100 g. Energy values of date fruits ranged from 3,725 kcal/kg (Soulag) to 3,870 kcal/kg (Soukari). Sucrose contents of date fruits changed between 1.02 % (Soulag) to 55.71 % (Soukari). Mineral contents of several date fruits were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Date samples contain potassium at a range between 7,468 mg/kg (Khulas) to 9,619 mg/kg (Soulag). Phosphorus contents of fruits were found between 1,848 mg/kg (Soulag) to 3,066 mg/kg (Rozaiz) and followed by magnesium and calcium. The highest Zn (9.33 mg/kg), Cu (4.27 mg/kg) and Mn (3.26 mg/kg) were found in Rozaiz, Soukari and Barhi samples, respectively. 相似文献
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19.
The United States has a highly varied landscape because of wide-ranging differences in combinations of climatic, geologic, edaphic, hydrologic, vegetative, and human management (land use) factors. Land uses are dynamic, with the types and rates of change dependent on a host of variables, including land accessibility, economic considerations, and the internal increase and movement of the human population. There is a convergence of evidence that ecoregions are very useful for organizing, interpreting, and reporting information about land-use dynamics. Ecoregion boundaries correspond well with patterns of land cover, urban settlement, agricultural variables, and resource-based industries. We implemented an ecoregion framework to document trends in contemporary land-cover and land-use dynamics over the conterminous United States from 1973 to 2000. Examples of results from six eastern ecoregions show that the relative abundance, grain of pattern, and human alteration of land-cover types organize well by ecoregion and that these characteristics of change, themselves, change through time. 相似文献