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21.
Soil contamination from urban and industrial activity: example of the mining district of Linares (southern Spain) 总被引:1,自引:0,他引:1
J. Martínez J. F. Llamas E. de Miguel J. Rey M. C. Hidalgo 《Environmental Geology》2008,54(4):669-677
The Linares region (southern Spain) has been subjected to two important sources of pollution: the intensive mining works and
the urban-industrial activity. To obtain a geochemical characterisation of the soil, 31 trace elements were analysed and 669
soil samples were collected. By means of clustering analysis, we identified groups of elements and grid squares in which relations
could be established concerning soil lithology, urban and industrial activities and the degree of pollution impact; in addition,
we were able to characterise the geochemical background of the study area. The multivariate study led us to identify four
factors. Particularly important was factor 2, which represented the elements associated with mineral paragenesis (Cu, Pb,
As, Co, Mn, Zn, Sn, Ba). This factor also contains elements related with an urban-industrial activity, such as Pb, Cu, Zn,
As and Ba. Furthermore, we identified factor 4, associating Ni, V and Cr, and which is related to the use of fuels. 相似文献
22.
Zhou Haiyan Zhou Xun Chai Rui Yu Lan Liu Chunhui Li Liangping 《Environmental Geology》2008,53(7):1483-1489
Thermal groundwater occurs in bedrock aquifers consisting of the dolomite of the Wumishan Group of the Jixianin System and
the Cambrian carbonate in the Xiaotangshan geothermal field near the northern margin of the North China Plain, China. The
hot water in the geothermal field of basin-type discharges partly in the form of the Xiaotangshan hot spring under natural
conditions. The hot water has TDS of less than 600 mg/L and is of Na·Ca-HCO3 type. The geothermal water receives recharge from precipitation in the mountain area with elevation of about 500 m above
sea level to the north of the spring. Thermal groundwater flows slowly south and southeast through a deep circulation with
a residence time of 224 years estimated with the Ra–Rn method. The Xiaotangshan hot spring dried up in the middle of the 1980s
owing to the increasing withdrawal of the hot water in the geothermal field in the past decades. The water level of the geothermal
system still falls continually at an annual average rate of about 2 m, although water temperature changes very little, indicating
that the recharge of such a geothermal system of basin-type is limited. Over-exploitation has a dramatic impact on the geothermal
system, and reduction in exploitation and reinjection are required for the sustainable usage of the hot water. 相似文献
23.
Phosphorus transport in shallow groundwater in peri-urban Kampala, Uganda: results from field and laboratory measurements 总被引:1,自引:0,他引:1
To understand Phosphorus (P) sources and transport processes in the subsurface in Bwaise III Parish, Kampala, P attenuation
and adsorption capacities of soils were studied in situ and from laboratory measurements. Relationships between sorption parameters
and soil matrix properties, rates and mechanism of the adsorption process and soil P fractions were also investigated. P was
generally higher in the wet than the dry season, but for both seasons, the maximum was 5 mgP/l. P transport mechanisms appeared
to be a combination of adsorption, precipitation, leaching from the soil media and by colloids with the latter two playing
an important role in the wet season. The sorption process comprised two phases with the first stage rate constants being about
fourfold those of the second stage. The Langmuir isotherm described the sorption data well (R
2 ≥ 0.95) with the second soil layer exhibiting the highest sorption maximum (C
max) (average value 0.6 ± 0.17 mgP/gDW). The best prediction of C
max had organic carbon, Ca, available P and soil pH. Residual P consisting mostly of organics was the main fraction in all the
layers followed by inorganic HCl-P and NaOH-P in the top and middle layers, respectively. Loosely bound P (NH4Cl-P) was the least fraction (<0.4% of total P) in all layers indicating the high binding capacity of P by the soils. The
study results suggest that P dynamics is related to Ca, Fe and organic carbon content of the soils. 相似文献
24.
Response of groundwater chemistry to water deliveries in the lower reaches of Tarim River,Northwest China 总被引:2,自引:0,他引:2
Yongjin Chen Kefa Zhou Yaning Chen Weihong Li Jiazhen Liu Tao Wang 《Environmental Geology》2008,53(6):1365-1373
In this paper, we analysed the monitored data from nine groundwater-monitoring transects in the lower reaches of Tarim River
during the five times of stream water deliveries to the river transect where the stream flow ceased. The results showed that
the groundwater depth in the lower reaches of Tarim River rose from −9.30 m before the conveyances to −8.17 and −6.50 m after
the first and second conveyances, −5.81 and −6.00 m after the third and fourth the conveyance, and −4.73 m after the fifth.
The horizontal extent of groundwater recharge was gradually enlarged along both sides of the channel of conveyance, i.e.,
from 250 m in width after the first conveyance to 1,050 m away from the channel after the fourth delivery. With the rising
groundwater level, the concentrations of major anions Cl−, SO42− and cations Ca2+, Mg2+, Na+, as well as total dissolved solids (TDS) in groundwater underwent a significant change. The spatial variations in groundwater
chemistry indicated that the groundwater chemistry at the transect near Daxihaizi Reservoir changed earlier than that farther
from it. In the same transect, the chemical variations were earlier in the monitoring well close to watercourse than that
farther away from the stream. In general, the concentration of the major ions and TDS at each monitoring well increased remarkably
when the water delivery started, and decreased with the continued water delivery, and then increased once again at the end
of the study period. Hence, the whole study period may be divided into three stages: the initial stage, the intermediate stage
and the later stage. According to the three stages of groundwater chemistry reaction to water delivery and the relationships
between groundwater chemical properties and groundwater depths, we educe that under the situation of water delivery, the optimum
groundwater depth in the lower reaches of the Tarim River should be −5 m. 相似文献
25.
Thomas B. Boving Mark H. Stolt Janelle Augenstern Brian Brosnan 《Environmental Geology》2008,55(3):571-582
The control of polluted surface runoff and the assessment of possible impacts on groundwater is a concern at the local and
regional scale. On this background, a study investigates possible impacts of organic and inorganic pollutants (including bacteria)
originating from a permeable asphalt parking lot on the water quality immediately beneath it. The functioning of the permeable
pavement, including clogging and restricted vertical percolation, was also evaluated. Four nested sample ports (shallow and
deep) were installed below low- and high-traffic areas, including one port outside the parking lot. At least initially there
was a good hydraulic connection between the parking surface and the shallow sample ports. The presence of a geotextile layer
at the base of the parking lot structure, however, was identified in lab tests as one factor restricting vertical percolation
to the deeper ports. Clogging of the permeable surface was most pronounced in heavy traffic areas and below snow pile storage
areas. Corroborated by high electric conductivity and chloride measurements, sand brought in by cars during winter was the
principal cause for clogging. No bacteria or BOD were found in percolating water. Polycyclic aromatic hydrocarbons (PAH) were
present at concentrations near minimum detection limit. Nutrients (nitrate and phosphate) were being leached into the ground
via the permeable parking lot surface at annual flux rates of 0.45–0.84 g/m2/year. A multi-species tracer test demonstrated a retention capacity of the permeable parking lot structure of >90% for metals
and 27% for nutrients, respectively. 相似文献
26.
Regional distribution pattern of groundwater heavy metals resulting from agricultural activities 总被引:18,自引:0,他引:18
Contaminations of groundwater by heavy metals due to agricultural activities are growing recently. The objective of this study
was to evaluate and map regional patterns of heavy metals (Cd, Zn and Cu) in groundwater on a plain with high agricultural
activities. The study was conducted to investigate the concentration of heavy metals and distribution in groundwater in regions
of Shush Danial and Andimeshk aquifers in the southern part of Iran. Presently, groundwater is the only appropriate and widely
used source of drinking water for rural and urban communities in this region. The region covers an area of 1,100 km2 between the Dez and Karkhe rivers, which lead to the Persian Gulf. For this study, the region was divided into four sub-regions
A, B, C and D. Additionally, 168 groundwater samples were collected from 42 water wells during the earlier months of 2004.
The flame atomic absorption spectrometry (AAS-Flame) was used to measure the concentration of heavy metals in water samples
and the Surfer software was used for determination of the contour map of metal distribution. The results demonstrated that
in all of the samples, Cd and Zn concentrations were below the EPA MCLG and EPA secondary standard, respectively. However,
the Cu contents of 4.8 % of all samples were higher than EPA MCL. It is also indicated that the concentrations of metals were
more pronounced at the southern part of the studied region than at the others. The analysis of fertilizers applied for agricultural
activities at this region also indicated that a great majority of the above-mentioned heavy metals were discharged into the
environment. Absence of confining layers, proximity to land surface, excess agricultural activities in the southern part and
groundwater flow direction that is generally from the north to the southern parts in this area make the southern region of
the Shush plain especially vulnerable to pollution by heavy metals than by other contaminants. 相似文献
27.
David P. Bacon Nash’at N. Ahmad Thomas J. Dunn Michael C. Monteith Ananthakrishna Sarma 《Natural Hazards》2008,44(3):317-327
By definition, a crisis is a situation that requires assistance to be managed. Hence, response to a crisis involves the merging
of local and non-local emergency response personnel. In this situation, it is critical that each participant: (1) know the
roles and responsibilities of each of the other participants; (2) know the capabilities of each of the participants; and (3)
have a common basis for action. For many types of natural disasters, this entails having a common operational picture of the unfolding events, including detailed information on the weather, both current and forecasted, that may impact on either
the emergency itself or on response activities. The Consequences Assessment Tool Set (CATS) is a comprehensive package of
hazard prediction models and casualty and damage assessment tools that provides a linkage between a modeled or observed effect
and the attendant consequences for populations, infrastructure, and resources, and, hence, provides the common operational
picture for emergency response. The Operational Multiscale Environment model with Grid Adaptivity (OMEGA) is an atmospheric
simulation system that links the latest methods in computational fluid dynamics and high-resolution gridding technologies
with numerical weather prediction to provide specific weather analysis and forecast capability that can be merged into the
geographic information system framework of CATS. This paper documents the problem of emergency response as an end-to-end system
and presents the integrated CATS–OMEGA system as a prototype of such a system that has been used successfully in a number
of different situations. 相似文献
28.
中国滑坡预测预报研究综述 总被引:14,自引:1,他引:13
滑坡预测预报是有效预防滑坡灾害的重要途径之一,这方面的研究不仅受到广泛重视,且硕果累累。将中国滑坡预测预报的研究历史划分为四个阶段:① 经验判断——被动防灾避灾阶段;② 定性——半定量分析预测预报阶段;③ 理论方法探索——检验预测预报阶段;④ 理论方法深化——综合应用预测预报阶段。从监测(观测)方法、预测预报方法,以及研究特点等方面进行简要回顾,总结已有监测方法(手段)、预测预报理论、方法的研究现状,认为尚存在:① 监测方法(手段),包括仪器、设备的精度不足;② 预测预报方法综合性、实用性不强;③ 预测预报专门理论尚待完善等问题。在分析的基础上,提出自己的观点,并进行了发展趋势展望。 相似文献
29.
M. Mejías J. Garcia-Orellana J. L. Plata M. Marina E. Garcia-Solsona B. Ballesteros P. Masqué J. López C. Fernández-Arrojo 《Environmental Geology》2008,54(3):521-536
A methodology for the characterization of deep carbonate aquifers has been developed and applied to El Maestrazgo Jurassic
aquifer in Castellón, Spain. Characterization of these aquifer formations, located at more than 300 m deep, consisted of a
previous phase of compilation, analysis and synthesis of the existing information about the area, followed by a coordinated
combination of different speciality studies: geology, stratigraphy, structural analysis, hydrogeology, hydrochemistry, geophysics
and remote sensing. Geological studies included geological mapping, definition of stratigraphical units and facies and structural
analysis. The aim of the hydrogeology study was to define aquifer formations, recharge area, aquifer points inventory and
groundwater flow directions for the establishment of piezometric and water quality observation nets. Special techniques were
applied, like thermal infrared aerial images and the evaluation of submarine groundwater discharge by means of natural radium
isotopes. Hydrochemical techniques, including majority elements characterization and stable isotopes (18O, 2H and 3H) determination, allowed classifying hydrochemical facies and establishing a renewal pattern for water within the system.
Geophysics was useful in determining the aquifer geometry, the features of the basement and the petrophysical characteristics
of the geological formations. Preliminary results show an important tectonic complexity and the possibilities for groundwater
uses in the area of study. 相似文献
30.
乌鲁木齐河流域地下水水质监测网设计 总被引:1,自引:0,他引:1
文章运用地下水易污性编图及污染源分布图法进行了乌鲁木齐河流域地下水水质监测网设计。共设计了130监测孔,现有46个监测孔,另需要84个新的监测孔。按监测类型分为面源监测点22个,点源监测点87个,重点水源地与泉水监测点21个。按监测运行分长期监测点55个,流域普查监测点75个。普查监测点监测频率为1次/5年,长期监测点监测频率为1次/年。首期有针对性地在污染严重的柴窝堡新化厂排污区、乌鲁木齐河谷老排污区、米泉污灌区、米泉工业污染区、老龙河污染区取了25个污染水样测试分析,结果显示地下水已经受到严重污染。 相似文献