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1.
José Antonio Grande María Luisa De La Torre María Santisteban Teresa Valente José Paulino Fernandez Eva Pérez-Ostalé 《水文科学杂志》2013,58(8):1503-1511
ABSTRACTThis paper presents hydrochemical data of an AMD stream, Poderosa Creek, in the Iberian Pyrite Belt, obtained between its source, in the Poderosa Mine portal, and its confluence with the Odiel River. The main objective is to establish potential interdependent relationships between sulphate and metal loads and the following physico-chemical variables: pH, electrical conductivity (EC), redox potential (EH) and dissolved oxygen (DO). All the parameters show an overall increasing tendency from the tunnel exit to the confluence at the Odiel River. The TDS and EC are two relevant exceptions. They behave similarly, showing a decreasing trend and a strong inflection that describes a minimum immediately after the discharging point. Spatial analysis combined with statistical tools reveal typical AMD processes and the respective physico-chemical implications. Inputs with distinctive hydrochemical signatures impose relevant modifications in the Poderosa Creek waters. This indicates low hydrochemical inertia and high vulnerability to external stimuli.
Editor D. Koutsoyiannis; Associate editor not assigned 相似文献
2.
AbstractThe aim of this study was to understand seasonal variations in the vertical structure of the water column, and to quantify the importance of the physical forces (solar radiation, wind and hydraulic retention time) that control mixing processes in a reservoir bordering the Pantanal floodplain. Samples were taken every three months in the reservoir centre, at four depths, for the measurement of nine physical and chemical water quality parameters. The reservoir presented a long stratification period with complete mixing in winter. The vertical structure showed that, during the stratification period, the upper layers of the reservoir are homogeneous and the physical and chemical composition only changes at greater depths. The wind acting over an extended period is the only factor that significantly influences the vertical structure in the reservoir, giving rise to mixing processes. Moreover, the position of the draw-off point in the upper layer of the reservoir, together with the reservoir depth, enhances vertical stability. 相似文献
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ABSTRACTWater temperature dynamics in a reservoir are affected by its bathymetry, climatic conditions and hydrological processes. Miyun Reservoir in China is a large and deep reservoir that experienced a large water level decline in 1999–2004 due to low rainfall and relatively high water supply to Beijing. To study changes of stratification characteristics in Miyun Reservoir from 1998 to 2011, the one-dimensional year-round lake model MINLAKE2010 was modified by adding a new selective withdraw module and a reservoir hydrological model. Simulation results under three scenarios demonstrated that the new MINLAKE2012 model accurately predicted daily water levels and temperature dynamics during the water level fluctuation period. The water level decline led to 7.6 and 3.8°C increases in the maximum and mean bottom temperatures and about 29 days reduction in the stratification days. These simulation results provide an insight into the thermal evolution of Miyun Reservoir during the planned future water filling process.
Editor D. Koutsoyiannis Associate editor M. Acreman 相似文献
5.
ABSTRACTIntegrated two-dimensional electrical resistivity imaging (ERI) and hydrochemical surveys were used to investigate the groundwater alluvial aquifer in Kuala Langat, Malaysia. The study in the Langat basin considered the thickness of the aquifer, the depth of the bedrock, the regions influenced by seawater intrusion, and the monitoring of water levels. The resistivity imaging results show that the upper layer consists of clay, while the second layer is an aquifer whose thickness varies mostly in the range of 10–30 m, and in some cases extends to 40 m. The bedrock depth varies from 30 to 65 m. The chemical analyses were carried out on groundwater samples from nine boreholes collected between 2008 and 2012. The analyses indicate that the total dissolved solids (TDS) exceed 1000 mg L-1 near the coastal area and are often less than 500 mg L-1 further inland. The ERI and hydrochemical analyses reveal that groundwater in the study area, especially towards the coast, is a mixture of brackish and fresh waters.
EDITOR D. Koutsoyiannis; ASSOCIATE EDITOR M.D. Fidelibus 相似文献
6.
ABSTRACTThis study describes the assessment of reservoir sedimentation of the Patratu Reservoir using Satellite Remote Sensing (SRS). The sedimentation assessment was carried out using satellite data and reservoir water level data from 2006 to 2012. Water spread area was analysed from satellite data. The Normalized Difference Water Index (NDWI) has been used to delineate open water features and to enhance the presence of water surface in satellite imagery of the Patratu Reservoir. Water spread area of the reservoir at a particular elevation on the date of the passing of the satellite was used to develop an elevation-area curve. For the present case, fluctuation of water level was found to vary from 387.096 to 406.152 m. The linear interpolation/extrapolation technique has been employed to assess the water spread area of Patratu Reservoir at different elevations. Further, these areas were used to compute the live storage capacity of the reservoir between two elevations by the Prismoidal formula. From the study, it was found that due to sedimentation, the live storage capacity of Patratu Reservoir has reduced from 101.95 to 89.96 hm3, thus showing capacity loss of 11.76% in a span of 44 years. To increase the live storage capacity of the reservoir it is proposed to adopt manual and mechanical digging combined with flushing for desilting of the deposited sediment.
EDITOR D. Koutsoyiannis ASSOCIATE EDITOR S. Kanae 相似文献
7.
《水文科学杂志》2013,58(3)
Abstract Abstract Groundwater in the Gaza Strip is the only source of water for domestic, agricultural and industrial uses. Extensive pumping has caused serious quantitative and qualitative problems in the aquifer. The hydrochemical facies are evaluated using the trilinear diagram for 200 water samples. Groundwater in the north and west is mostly characterized by Ca-Mg-HCO3 facies (alkaline water), and in the south and east by Na-Cl-SO4 facies (saline water). Sand dunes and rainfall are the major factors controlling the distribution of hydrochemical facies. The eastern edge of the sand dune belt is considered the barrier that separates the two major facies. Brackish water flowing from the east is mixed with rainwater which infiltrates through the sand dunes to the aquifer. Other factors, e.g. seawater intrusion and extensive pumping, play a minor role in the distribution of the hydrochemical facies. 相似文献
8.
G.E. Petts T.R. Foulger D.J. Gilvear J.D. Pratts M.C. Thomas 《Journal of Hydrology》1985,80(3-4):371-389
Data are presented to describe the at-a-station variations and downstream patterns of change, of flow and water quality during the passage of a controlled reservoir release along a short 10 km reach, immediatly below the dam. By removing the effects of runoff from diverse catchment sources, which characterise natural flow variations, reservoir releases are used to focus attention on the effects of channel characteristics. At each of four main sites, measurements were made at 4 min intervals for at least 4 h. The data illustrate the dominant effect of initial flow conditions, especially channel roughness, upon wave movement, suspended solids transport, and hydrochemical lags. Variations in the patterns of change appear to relate to spatially variable in-channel sources which can be particularly influential within such short study reaches. 相似文献
9.
Earthquake-induced variations in the composition of the water in the geothermal reservoir at Vulcano Island, Italy 总被引：1，自引：0，他引：1
During 1979–1989, variations were observed in the oxygen composition of the water contained in the geothermal reservoir at Vulcano Island, Italy.The reservoir water, that has a magmatic origin, showed an oxygen composition of +1.0±0.5‰ δ18O during periods without local tectonic earthquakes, and an oxygen composition of +3.4±0.5‰ δ18O after the highest-energy seismic activity that occurred recently near the island. A slight increase of the δ18O value in the reservoir water was also observed after a low-energy sequence of tectonic earthquakes that occurred at very shallow depth just beneath Vulcano Island. These 18O variations in the reservoir water are consistent with earthquake-induced increases in the contribution from high-temperature δ18O-rich magmatic condensate to the geothermal reservoir, and with subsequent decreases in the δ18O value due to 18O exchanges at the temporarily increased reservoir temperature during reactions between the highly reactive magmatic condensate and the local rocks.Only minor changes in the deuterium composition of the reservoir water occurred with time, as the δD value in the magmatic condensate released from the magma after major local earthquakes quickly approached the δD value of the water contained in the geothermal reservoir.Also the chloride concentration in the reservoir water appears to be linked to the contribution from the magmatic fluid. This chloride content seems not to have undergone major changes with time, as it may be buffered by temporary increases in the reservoir temperature up to values >300°C induced by major local earthquakes. This mechanism may possibly occur also in other magmatic–hydrothermal systems. 相似文献
10.
XU JIONGXIN 《水文科学杂志》2013,58(6):837-849
Abstract A study on the suspended sediment transportation downstream from the Danjiangkou Reservoir in China has shown that the dynamics of suspended sediment grain size are complicated. During the period when the reservoir was used for flood retention, the suspended sediment median size decreased gradually; after entering the period when the reservoir was used for water storage, the median size started to increase, reaching a maximum, and then decreased again. These variations correspond to different stages of channel adjustment. At the stage with dominant downcutting, most of the downstream reservoir sediment comes from bed downcutting, and thus the suspended sediment median size becomes coarser and coarser; at the succeeding stage with dominant channel widening, a majority of the suspended sediment comes from bank erosion, and so its median size becomes finer. This phenomenon can be regarded as a reflection of the complex response of channel adjustment in the characteristics of suspended sediment transportation downstream from a reservoir. 相似文献
11.
AbstractA semi-distributed hydrological model and reservoir optimization algorithm are used to evaluate the potential impacts of climate change on existing and proposed reservoirs in the Sonora River Basin, Mexico. Inter-annual climatic variability, a bimodal precipitation regime and climate change uncertainties present challenges to water resource management in the region. Hydrological assessments are conducted for three meteorological products during a historical period and a future climate change scenario. Historical (1990–2000) and future (2031–2040) projections were derived from a mesoscale model forced with boundary conditions from a general circulation model under a high emissions scenario. The results reveal significantly higher precipitation, reservoir inflows, elevations and releases in the future relative to historical simulations. Furthermore, hydrological seasonality might be altered with a shift toward earlier water supply during the North American monsoon. The proposed infrastructure would have a limited ability to ameliorate future conditions, with more benefits in a tributary with lower flood hazard. These projections of the impacts of climate change and its interaction with infrastructure should be of interest to water resources managers in arid and semi-arid regions.
Editor D. Koutsoyiannis 相似文献
12.
A. Longinelli B. Stenni L. Genoni O. Flora C. Defrancesco G. Pellegrini 《Journal of Hydrology》2008,360(1-4):103-116
Discontinuous measurements of the isotopic composition of surface water samples of the Garda lake carried out between 1998 and 2006 showed almost constant δ18O, δD and d-excess values through time. During 2006 and 2007 monthly vertical profiles of water samples were collected in the northernmost section of the lake, not far from the main inflow (Sarca river) to check whether there was any detectable influence from this inflowing river and whether there was a vertical isotopic stratification of the lake water. The isotopic measurement of water samples from the vertical profiles yielded isotopic values which were almost equal to those obtained from surface waters showing no detectable effect of the inflowing river water and no isotopic vertical stratification. The attempt to evaluate the evaporation rate of lake water by means of current models was totally unsuccessful. Despite the marked summer warming of the surface layer no isotopic fractionation related to evaporation processes could be detected. This anomalous behaviour may be related to the large amount of spring and summer precipitation characteristic of this area. The water balance of the lake calculated according to the amount of the inflowing water (Sarca river water plus rain water on the lake plus 20% of the precipitations on the whole catchment basin) and to the amount of outflowing water (Mincio river) showed a large imbalance, the river outflow alone resulting on average, during the last decade, at least double the inflow. To explain this imbalance of the lake, a large recharge by concealed groundwater is suggested: its isotopic composition should be quite close to the mean isotopic composition of precipitations over that area. This would be in agreement with the almost constant isotopic composition of both surface and deep waters and with the lack of vertical isotopic stratification. A few measurements of the tritium concentration carried out on lake water show values that are considerably higher than modern tritium values either in precipitation or in the Sarca river water: these results are in good agreement with the hypothesis of a recharge of the lake by deep aquifers. 相似文献
13.
ABSTRACTThe water balance dynamics and runoff components of a tropical forested catchment (46?km2) on the southwestern Pacific coast of Nicaragua were studied combining hydrometry, geological characterization and hydrochemical and isotopic tracers (three-component hydrograph separation). The climatic water balance was estimated for 2010/11, 2011/12 and 2012/13 with net values of 811?mm year-1, 782?mm year-1 and –447?mm year-1, respectively. Runoff components were studied at different spatial and temporal scales, demonstrating that different sources and temporal contributions are controlled by dominant landscape elements and antecedent rainfall. In forested sub-catchments, permeable soils, stratigraphy and steep slopes favour subsurface stormflow generation contributing 50% and 53% to total discharge. At catchment scale, landscape elements such as smooth slopes, wide valleys, deeper soils and water table allow groundwater recharge during rainfall events. Groundwater dominates the hydrograph (50% of total discharge) under dry prior conditions. However, low soil infiltration capacity generates a larger surface runoff component (42%) under wet prior conditions which dominates total discharge. Our results show that forested areas are important to reduce surface runoff and thus soil degradation, which is relevant for the design of water management plans.
Editor D. Koutsoyiannis Associate editor D. Gerten 相似文献
14.
Abstract Accurate estimation of groundwater recharge is essential for the proper management of aquifers. A study of water isotope (δ2H, δ18O) depth profiles was carried out to estimate groundwater recharge in the Densu River basin in Ghana, at three chosen observation sites that differ in their altitude, geology, climate and vegetation. Water isotopes and water contents were analysed with depth to determine water flow in the unsaturated zone. The measured data showed isotope enrichment in the pore water near the soil surface due to evaporation. Seasonal variations in the isotope signal of the pore water were also observed to a depth of 2.75 m. Below that depth, the seasonal variation of the isotope signal was attenuated due to diffusion/dispersion and low water flow velocities. Groundwater recharge rates were determined by numerical modelling of the unsaturated water flow and water isotope transport. Different groundwater recharge rates were computed at the three observation sites and were found to vary between 94 and 182 mm/year (± max. 7%). Further, the approximate peak-shift method was applied to give information about groundwater recharge rates. Although this simple method neglects variations in flow conditions and only considers advective transport, it yielded mean groundwater recharge rates of 110–250 mm/year (± max. 30%), which were in the same order of magnitude as computed numerical modelling values. Integrating these site-specific groundwater recharge rates to the whole catchment indicates that more water is potentially renewed than consumed nowadays. With increases in population and irrigation, more clean water is required, and knowledge about groundwater recharge rates – essential for improving the groundwater management in the Densu River basin – can be easily obtained by measuring water isotope depth profiles and applying a simple peak-shift approach. Citation Adomako, D., Maloszewski, P., Stumpp, C., Osae, S. & Akiti, T. T. (2010) Estimating groundwater recharge from water isotope (δ2H, δ18O) depth profiles in the Densu River basin, Ghana. Hydrol. Sci. J. 55(8), 1405–1416. 相似文献
15.
《水文科学杂志》2013,58(5)
Abstract Uninterrupted records of annual discharge from the Yangtze River to the sea (at Datong Hydrographical Station) began in the 1950s. This series shows no significant trend. However, at Hankou, a station upstream from Datong, annual discharges have been observed since 1865 almost without gaps. The annual discharges at Datong and Hankou were found to be closely correlated. Based on the regression equation, the missing annual discharges at Datong were estimated and a time series from 1865 to 2004 was established. Although the annual discharge has varied greatly, it shows a significant decreasing trend. The trendline revealed an 8.2% decrease from 1865 to 2004. The decrease in discharge was attributed to increases in water consumption and reservoir construction, while the interannual variations were related to climate variability. The decreasing trend in discharge is expected to continue in the coming decades due to human activities. This decreasing trend should be taken into account in the decision making on the South-to-North-Water Diversion projects. 相似文献
16.
AbstractOn the slopes of the embankment of the Al-Khod groundwater recharge–flood protection dam (Oman), a band of scrub vegetation community emerged after torrential rains and temporary filling of the dam reservoir. Species composition differs markedly on both sides of the embankment, with many exotics found on the reservoir side and more typical gravel-desert species on the outside. Hydro-ecologically, the vegetation is interpreted as the footprint of a temporary storage of water, which is a small-sized groundwater mound within the permeable shoulder of the levee. The levee, as an anthropogenic landform, induces a U-turn (gravitational slumping–lateral seepage–transpirational moisture ascent) topology of seepage. The Lembke method of successive variations of steady states is used in modelling the water table dynamics. In the early stage of the mound decay, outflow through a seepage face of the shoulder is modelled by the Barenblatt slumping parabola of the phreatic-zone part of the flow domain, which is perfectly matched with the Youngs exact solution for a purely horizontal flow through a porous wedge. At the stitching cross-section, the flow rates and saturated depths in the two zones coincide. The late stage of mound evolution is characterized by transpiration by the plant roots projected onto a shrinking free surface, with the Barenblatt and Youngs solutions conjugated but without the outcrop of the saturated mound on the levee slope. Ordinary differential equations for the sliding or descending locus of the intersection of the parabola and the triangle hypotenuse are integrated in a closed form or by the Runge-Kutta method. The dwindling saturated volume and the rate of drainage are obtained. They can be used in assessments of the hydro-ecological sustainability of slope-rooted shrubs (vegetation survival between rare rainfall episodes).
Editor D. Koutsoyiannis; Associate editor A. Porporato 相似文献
17.
《水文科学杂志》2013,58(4):857-867
Abstract Water abstraction for irrigation upstream of a reservoir and its impact on reservoir yield and reliability are studied. Water demand and availability are strongly related in semi-arid environments where the irrigation sector is responsible for a large part of consumptive water use. Variations in water abstractions for irrigation depend on irrigation requirements per hectare and the size of the irrigated area. The Orós Reservoir in semi-arid Northeast Brazil has been taken as a case study. The results show that water abstracttion for irrigation is of significant importance for reservoir yield and reliability. Yield—reliability simulations for the study area show that taking into account upstream water abstraction for a reservoir yield of 20.0 m3/s results in a water-scarcity probability of 10% on an annual basis (90% reliability). This is only 5% if up-stream abstraction for irrigation is ignored. This study shows that observed land-use changes in the study area do have a significant impact on reservoir yield reliability. The variability of upstream water abstraction was found to be of low importance for reservoir yield and reliability. 相似文献
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Abstract Poyang Lake is the largest freshwater lake in China, and plays a major role in flood mitigation, restoration and conservation of the ecological environment in the middle Yangtze River basin. Sediment load and streamflow variations in Poyang Lake basin are important for the scouring and deposition changes of this lake. However, these hydrological processes are heavily influenced by human activities, such as construction of water reservoirs, and land-use/land cover changes. By thorough analysis of long series of sediment and streamflow obtained from five major hydrological stations, we systematically investigated the spatial and temporal patterns of these hydrological processes and the hydrological responses to human activities using the Mann-Kendall trend test, the double cumulative mass curve and the linear regression method. The results show: (1) no significant change in streamflow followed by an increasing tendency after the 1990s that turns to be decreasing about 2000; and (2) a sharp increase of sediment load during the late 1960s and 1970s triggered by extensive deforestation (during the “Cultural Revolution” in China) followed by a tendency to decrease after the early 1980s. Construction of water reservoirs has greatly reduced the sediment load of the Poyang Lake basin, and this is particularly the case in the Ganjiang River, where the sediment load changes may be attributed to the trapping effects of the Wan'an Reservoir, the largest water reservoir within the Poyang Lake basin. There is no evidence to corroborate the influence of water reservoirs on the streamflow variations. It seems that the streamflow variations are subject mainly to precipitation changes, but this requires further analysis. The current study may be of scientific and practical benefit in the conservation and restoration of Poyang Lake, as a kind of wetland, and also in flood mitigation in the middle Yangtze River basin that is under the influence of human activities. Citation Zhang, Q., Sun, P., Jiang, T. & Chen, X.-H. (2011) Spatio-temporal patterns of hydrological processes and their hydrological responses to human activities in the Poyang Lake basin, China. Hydrol. Sci. J. 56(2), 305–318. 相似文献
19.
《水文科学杂志》2013,58(6)
Abstract Discharge measurements, precipitation observations and hydrochemical samples from catchments of the Callejon de Huaylas watershed draining the Cordillera Blanca to the Rio Santa, Peru, facilitate estimating the glacier meltwater contribution to streamflow over different spatial scales using water balance and end-member mixing computations. A monthly water balance of the Yanamarey Glacier catchment shows elevated annual discharge over December 2001–July 2004 compared to 1998–1999, with net glacier mass loss in all months. Glacial melt now accounts for an estimated 58% of annual mean discharge, 23% greater than 1998–1999. At Lake Querococha, below Yanamarey (3.4% glacierized), a hydrochemical end-member mixing model estimates that 50% of the streamflow is derived from the glacier catchment. Average concentrations from the Rio Santa leaving the Callejon de Huaylas (8% glacierized) are modelled as a mixture with 66% deriving from glacierized tributaries of the Cordillera Blanca as opposed to the non-glacierized Cordillera Negra end member. 相似文献
20.
Abstract On the basis of the degree of mineralization, the groundwater of Apan-Tochac sub-basin may be considered as fresh (TDS < 500 ppm). However, chlorination is necessary to make it fit for human consumption. Major ion analyses of over 235 water samples reveal a striking relationship between hydrochemical evolution and the groundwater flow system. A high content of total dissolved solids, and low values of the Ca:Mg ratio are present in wells located on the plain (discharge zone), whereas opposite conditions are associated with wells located in higher regions (recharge zone). Statistical data analysis using the method of principal components allowed to differentiation of two hydrochemical families: (a) low mineralization corresponding to the recharge zone, and (b) high mineralization corresponding to the discharge zone. Waters of the Ca + Mg + HCO3, and Na + Mg + HCO3 hydrochemical fades are present and the former is dominant. The water is slightly alkaline, having slight problems of salinity during the year owing mainly to Ca2+HCO3 ? and Na+Cl? salts. The hydrochemistry of the groundwater reflects the pattern of local groundwater flow for this sub-basin. 相似文献