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1.
Abstract

The detention storage in a drainage basin under the equilibrium condition is an important parameter in rainfall-runoff modelling. As this parameter is an efficient measure of the basin response to rainfall, it is commonly used as a basis of approximation of a complex basin by a simpler one. For flows on an overland plane, the equilibrium storage has also been used as a basis of determining the resistance coefficient of the overland surface. A formula is derived, based on the kinematic wave theory, for the equilibrium detention storage for a series of planes. For practical applications, the formula is further developed in terms of the Manning resistance coefficient. The derived formulae are all consistent with the published formulae for a single plane.  相似文献   

2.
The near-to-nature approach has been established as best practice for stormwater management. However, pollutant mobility within such systems and its impact on small receiving waters are partly unexplained. The study takes place in an urbanised headwater catchment in south-western Germany with an area of 0.4 km2. Runoff from roofs, roads, parking lots and gardens is collected in wells or trenches and stored in private and public dry detention basins. Accordingly, this study investigates pollutant input to a detention pond, removal efficiency and the associated effects on the receiving water.Grab samples with high temporal resolution of the receiving water (16 flood events with 315 samples and 41 baseflow samples), the three inflows of the detention basin and its outflow (four flood events with 64 samples) were taken. The outflow of the dry pond is recovered in the hydro- and chemographs of the receiving water. Runoff from roads with increased traffic volume caused the highest PAH inputs and runoff from the residential area showed the highest zinc concentrations, which partly infringe European Environmental Quality Standards. Yearly pollutant inputs (DOC, TSS, PAH, nutrients, metals) from the settlement into the tributary are reduced in the detention pond by up to 80%.  相似文献   

3.
Abstract

By sprinkling an experimental plot with different intensities of simulated rainfall starting with different initial conditions of soil moisture, the variations of infiltration capacity and consequently the response of the soil surface to runoff are evaluated. The following values are successively determined from experimental data: the mean depth of surface storage; the mean depth of detention and the parameters of a chosen infiltration formula.  相似文献   

4.
Abstract

Tile drainage influences infiltration and surface runoff and is thus an important factor in the erosion process. Tile drainage reduces surface runoff, but questions abound on its influence on sediment transport through its dense network and into the stream network. The impact of subsurface tiling on upland erosion rates in the Le Sueur River watershed, USA, was assessed using the Water Erosion Prediction Project (WEPP) model. Six different scenarios of tile drainage with varying drainage coefficient and management type (no till and autumn mulch-till) were evaluated. The mean annual surface runoff depth, soil loss rate and sediment delivery ratio (SDR) for croplands, based on a 30-year simulation for the watershed with untiled autumn mulch-till (Scenario 1), were estimated to be 83.5 mm, 0.27 kg/m2 and 86.7%, respectively; on no-till management systems (Scenario 4), the respective results were 72.3 mm, 0.06 kg/m2 and 88.2%. Tile drains reduced surface runoff, soil loss and SDR estimates for Scenario 1 by, on average, 14.5, 8.1 and 7.9%, respectively; and for Scenario 4 by an estimated 31.5, 22.1 and 20.2%, respectively. The impact of tile drains on surface runoff, soil loss and SDR was greater under the no-till management system than under the autumn mulch-till management system. Comparison of WEPP outputs with those of the Soil Water Assessment Tool (SWAT) showed differences between the two methods.

Editor Z.W. Kundzewicz

Citation Maalim, F.K. and Melesse. A.M., 2013. Modelling impacts of subsurface drainage on surface runoff and sediment yield in the Le Sueur Watershed in Minnesota, USA. Hydrological Sciences Journal, 58 (3), 570–586.  相似文献   

5.
《水文科学杂志》2013,58(4):665-671
Abstract

Analytical solutions of a routing problem for storm water flowing through a linear reservoir are presented for the assumption of trapezoidal-shaped inflow hydrograph. The maximum ponded (water) depth in the detention basin is chosen as a main design criterion. Calculations are carried out for a given rain recurrence interval but for various rain durations and sand filter surface areas to reach the maximum permitted ponded depth. A design example is also provided.  相似文献   

6.
Abstract

Mosul Dam is one of the biggest hydraulic structures in Iraq. Its storage capacity is 11.11 × 109 m3 at a maximum operation level of 330 m a.s.l. The dam became operational in 1986 and no survey has been conducted to determine its storage capacity and establish new operational curves since this date. A topographic map of scale 1:50 000 dated 1983 was converted into triangulated irregular network (TIN) format using the ArcGIS program to evaluate the operational curves. Then the reservoir was surveyed in 2011 to establish the reduction in its storage capacity and to develop new operational curves. The results indicated that the reduction in the storage capacity of the reservoir was 14.73%. This implies that the rate of sedimentation within the reservoir was 45.72 × 106 m3 year?1. These results indicate that most of the sediment was deposited within the upper zone of the reservoir where the River Tigris enters the reservoir.

Editor D. Koutsoyiannis

Citation Issa, E.I., Al-Ansari, N., and Knutsson, S., 2013. Sedimentation and new operational curves for Mosul Dam, Iraq. Hydrological Sciences Journal, 58 (7), 1456–1466.  相似文献   

7.
Surface infiltration and internal drainage properties of five soil types from arid drylands of South Africa were studied under double ring infiltrometer, rainfall simulation plots (1 m2) and instantaneous drainage plots (9 m2). Changes in soil water content during 40 minute rainfall simulation for a rainstorm with average intensity of 1.61 mm min?1 and 30 day drainage period were measured at various depths by 1.5 m long capacitance soil water measuring (DFM) probe. Different (P < 0.05) mean surface steady infiltration rate ranged from 0.05 to 4.47 mm min?1 and had a negative power relationship (R 2 = 0.65) with horizon clay plus fine silt content. Power regression (R 2 ≥ 86%) described rainstorm infiltration and obtained steady rates within an average time of 15 minutes. Mean total infiltrated soil water content was lowest (P < 0.05) from surface horizons with either 47.7% clay plus fine silt content or bulk density of 1.91 g cm?3 and exchangeable sodium of not less than 44 mg kg?1. Surface horizons with lower surface bulk density and total sand fraction of more than 72% had infiltrated depth and mean total infiltrated soil water content up to 40 cm deeper and 0.55 mm mm?1 greater, respectively. Drainage rate at drained upper limit calculated from the Wilcox drainage model (R 2 ≤ 0.97%) was 0.2 mm day?1 or less were from underlying horizons with either clay plus fine silt of 45% or soft calcium carbonate. Higher drainage rate with accumulative drainage amount greater than 60 mm were from soil profile horizons with clay plus fine silt content of less than 20% and above unity steady infiltration rates. Rainstorm infiltration and drainage rates was shown to depend on permeability and coarseness of the respective soil surface and subsurface horizons; a phenomenon critical for harnessing rain and flood water to recharge groundwater. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

8.
Abstract

Surface runoff and drainage were evaluated for southern Brazilian soils subjected to different rainfall intensities and management practices. Soils received up to four applications of simulated rainfall in sequences with one application per day. Seven lysimeters, each of 1 m3 volume, were used to measure drainage volume, with measurement of initial and final water content, times at which surface runoff and lysimeter drainage began, and the volume rates of flow. At the end of the second test, soils were subjected to two levels of disturbance (denoted by low and high soil movement) by opening furrows. These cultivation treatments altered the times at which lysimeter surface runoff and drainage were initiated, the rates of surface runoff, the final infiltration and internal drainage, and the components of the water balance throughout the series of trials. Mean times at which surface runoff was initiated in lysimeters subjected to greater soil disturbance were longer than those with little soil disturbance. Final infiltration rates were greater in lysimeters with little soil disturbance. It was also found that lysimeter surface runoff generation was influenced by the state of development of maize grown in the lysimeter.
Editor D. Koutsoyiannis; Associate editor G. Mahé  相似文献   

9.
A physically based snow-evolution modelling system (SnowModel) that includes four sub-models: MicroMet, EnBal, SnowPack, and SnowTran-3D, was used to simulate eight full-year evolutions of snow accumulation, distribution, sublimation, and surface melt from glaciers in the Zackenberg river drainage basin, in north-east Greenland. Meteorological observations from two meteorological stations were used as model inputs, and spatial snow depth observations, snow melt depletion curves from photographic time lapse, and a satellite image were used for model testing of snow and melt simulations, which differ from previous SnowModel tests methods used on Greenland glaciers. Modelled test-period-average end-of-winter snow water equivalent (SWE) depth for the depletion area differs by a maximum of 14 mm w.eq., or ∼6%, more than the observed, and modelled test-period-average snow cover extent differs by a maximum of 5%, or 0·8 km2, less than the observed. Furthermore, comparison with a satellite image indicated a 7% discrepancy between observed and modelled snow cover extent for the entire drainage basin. About 18% (31 mm w.eq.) of the solid precipitation was returned to the atmosphere by sublimation. Modelled mean annual snow melt and glacier ice melt for the glaciers in the Zackenberg river drainage basin from 1997 through 2005 (September–August) averaged 207 mm w.eq. year−1 and 1198 mm w.eq. year−1, respectively, yielding a total averaging 1405 mm w.eq. year−1. Total modelled mean annual surface melt varied from 960 mm w.eq. year−1 to 1989 mm w.eq. year−1. The surface-melt period started between mid-May and the beginning of June and lasted until mid-September. Annual calculated runoff averaged 1487 mm w.eq. year−1 (∼150 × 106 m3) (1997–2005) with variations from 1031 mm w.eq. year−1 to 2051 mm w.eq. year−1. The model simulated a total glacier recession averaging − 1347 mm w.eq. year−1 (∼136 × 106 m3) (1997–2005), which was almost equal to previous basin average hydrological water balance storage studies − 244 mm w.eq. year−1 (∼125 × 106 m3) (1997–2003). Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

10.
Abstract

Hydrological processes of the wetland complex in the Prairie Pothole Region (PPR) are difficult to model, partly due to a lack of wetland morphology data. We used Light Detection And Ranging (LiDAR) data sets to derive wetland features; we then modelled rainfall, snowfall, snowmelt, runoff, evaporation, the “fill-and-spill” mechanism, shallow groundwater loss, and the effect of wet and dry conditions. For large wetlands with a volume greater than thousands of cubic metres (e.g. about 3000 m3), the modelled water volume agreed fairly well with observations; however, it did not succeed for small wetlands (e.g. volume less than 450 m3). Despite the failure for small wetlands, the modelled water area of the wetland complex coincided well with interpretation of aerial photographs, showing a linear regression with R2 of around 0.80 and a mean average error of around 0.55 km2. The next step is to improve the water budget modelling for small wetlands.

Editor Z.W. Kundzewicz; Associate editor X. Chen

Citation Huang, S.L., Young, C., Abdul-Aziz, O.I., Dahal, D., Feng, M., and Liu, S.G., 2013. Simulating the water budget of a Prairie Potholes complex from LiDAR and hydrological models in North Dakota, USA. Hydrological Sciences Journal, 58 (7), 1434–1444.  相似文献   

11.
ABSTRACT

The 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   

12.
In this study,the detention rate of detention pond was defined to include both reduction and delay of peak flow.Flood routing experiments,with various combinations of inflow hydrographs and outlet devices in an in-site detention pond,were performed to examine the effectiveness of two analysis methods,namely the simplified method and the hydrological routing method;and to compare the detention rate of two types of outlet,namely the rectangular sharp-crested weir and the rectangular orifice.Comparison between...  相似文献   

13.
14.
Seasonal soil water dynamics were measured on a hillslope transect in the jarrah forest of southwest Western Australia over the period 1984-86 using mercury manometer tensiometers, gypsum blocks, and a neutron moisture meter. The soil water potential gradients indicated downward vertical drainage flux through winter and spring. There was generally a change to an upwards flux in early summer which was sustained through to autumn. A shallow ephemeral saturation zone was identified in and above a duricrust layer, lasting up to three days after heavy, late winter rainfall. The annual maximum to minimum unsaturated soil water storage on the hillslope was approximately 400 mm to 6 m depth and 480 mm to 15 m depth. This did not change significantly in years of substantially different winter rainfall. The magnitude of seasonal soil water storage was similar to other forested areas with deep soil profiles. The depth of observable infiltration was dependent on annual rainfall. This was consistent with the observation that groundwater levels responded to rainfall over the whole hillslope in wet years but only responded on the lower slopes in dry years. The average summer drying rate of the soil profile to 6 m depth of 3.5 mm day?1 was within the range of values reported for forests elsewhere. In late summer, following an extended drought period, the drying rate decreased downslope but increased midslope.  相似文献   

15.
ABSTRACT

Sir Charles Cotton (1964) has pointed out that in an earlier paper (Carlston, 1963) which related drainage density to hydrology, there was insufficient emphasis on the role of climate in its effect on drainage density. Re-examination of the relation of drainage density to base flow in the 15 basins originally described has revealed additional evidence that base flow is affected by precipitation or recharge (a climatic variable), while varying inversely with drainage density.

Within the climatic region studied in the earlier paper (the Humid Subtropical Climate of the eastern U. S.), no evidence could be found that amount or intensity of rainfall affected the intensity of flood runoff or the scale of drainage density. In comparison with other climates, however, such as the Marine West Coast Climate, it is possible that the less intense precipitation of a marine climate may result in lower runoff intensities and lower drainage densities, however the lower mean temperatures of such climates may develop soils of generally higher infiltration capacity which would produce lower drainage densities.

A progressive increase in aridity results in a decrease in soil and vegetal cover which greatly magnifies the range of drainage densities characteristic of semi-arid regions. In such regions, where the land sur-face has a good infiltration capacity rainfall sinks readily into the dry soil (although recharge to ground water may be negligible), and runoff is virtually zero, as is drainage density, Impermeable terranes devoid of vegetal and soil cover reject the rain, runoff is briefly total and drainage density may be greatly magnified, as in the South Dakota Badlands, where drainage density runs into the hundreds. Arid or Desert Climates should produce erosional landforms with generally high drainage densities, though not reaching the magnitudes of drainage density found in the semi-arid badlands where rainfall intensities are much higher.  相似文献   

16.
Abstract

Abstract Since the end of the 1950s, suspended matter measurements have been carried out in the streams and rivers of Cameroon. Despite the fact that these are often point measurements, they provide a framework for a global approach towards studying the regimes of suspended sediment transport in these rivers. The objective here is to assess the intensity of sediment transport and to determine the principal factors which influence it, according to the main climatic units. The influence of human activities is pointed out. It appears that steep slopes, population density, soil cultivation and cattle grazing are the essential factors. The sediment load in these rivers is increasing with latitude with 20–40 g m-3 at the Equator, 80–100 g m-3 in the transition zones and 150–160 g m-3 in the dry tropical zones. The choice of drainage basin size for the characterisation of the rate of effective erosion is indispensable. In fact, in large drainage basins (5 × 104 km2), there is an integration of heterogeneous geomorphological, phytogeographical, pedological and anthropogenic characteristics into average characteristics which do not show the influence of local conditions on sediment transport.  相似文献   

17.
Abstract

Groundwater of the Tertiary-Quaternary Formations in the Jeloula basin (Central Tunisia), together with rain and surface waters, were analysed to investigate the mineralization processes, the origin of the water and its recharge sources. The water samples present a large spatial variability of chemical facies which is related to their interaction with the geological formations. The main sources of the water mineralization are the dissolution of evaporitic and carbonate minerals and cation exchange reactions. Stable isotopes indicate that most groundwater samples originate from infiltration of modern precipitation. Surface water samples from small dam reservoirs show a 18O/2H enrichment, which is typical of water exposed to open-surface evaporation in a semi-arid region. Considerable data of 3H and 14C allow the qualitative identification of the present-day recharge that is probably supplied by infiltration of recent flood waters in the Wadi El Hamra valley, and by direct infiltration of meteoric water through the local carbonate outcrops.

Editor D. Koutsoyiannis; Associate editor S. Faye  相似文献   

18.
内陆水体是大气CO2收支估算的重要组成部分。农业流域分布着大量池塘景观水体,且具备蓄洪抗旱、消纳污染、水产养殖等多种功能。但是,农业流域不同功能的小型池塘CO2排放特征尚不清楚。本研究以极具农业流域代表性的烔炀河流域为研究对象,选取流域中用于水产养殖(养殖塘)、生活污水承纳(村塘)、农业灌溉(农塘)、蓄水(水塘)的4个功能不同的景观池塘,基于为期1年的野外实地观测,以明确农业流域小型池塘CO2排放特征。结果表明,不同功能池塘水体CO2排放差异显著,受养殖活动、生活污水输入和农田灌溉等人类活动影响,养殖塘((80.37±100.39) mmol/(m2·d))、村塘((48.69±65.89) mmol/(m2·d))和农塘((13.50±15.81) mmol/(m2·d))是大气CO2的热点排放源,其CO2排放通量分别是自然蓄水塘((4.52±23.26) mmol/(m2·d))的18、11和3倍。统计分析也表明,该流域池塘CO2排放变化总体上受溶解氧、营养盐等因素驱动。4个不同景观池塘CO2排放通量全年均值为(37.31±67.47) mmol/(m2·d),是不容忽视的CO2排放源,其中养殖塘和村塘具有较高的CO2排放潜力,在未来研究中需要重点关注。  相似文献   

19.
Abstract

A one-dimensional water quantity and quality mathematical model was developed to evaluate the effects of joint gate–pump operation in terms of water withdrawal for pollutant flushing. The study was carried out in dry seasons in the Foshan River channel, China. The results indicate that the input of freshwater into the upper and middle reaches of the Foshan River can improve the water quality of the lower reaches. However, the backwater effect due to water diversion in the middle reaches of the river can greatly offset the cleaning processes in the upper reaches of the Foshan River. The results indicate that water quality in the upper Foshan River (Jiebian) may degrade with an increase in the rate of water withdrawal from the middle river when the discharge pumped from the upper Foshan River is less than 10m3/s; optimal water quality improvement is obtained with discharge values of 30 and 20 m3/s, respectively, at the upper and middle reaches of the Foshan River.

Editor D. Koutsoyiannis

Citation Liu, C.-L., Jiang, T., Zhang, Q., Zhu, S. and Li, K., 2012. Modelling of water withdrawal for pollutant flushing in the tidal river network, Pearl River Delta, China. Hydrological Sciences Journal, 57 (3), 576–590.  相似文献   

20.
Abstract

The quantification of natural recharge rate is a prerequisite for efficient and sustainable groundwater resources management. Since groundwater is the only source of water supply in the West Bank, it is of utmost importance to estimate the rate of replenishment of the aquifers. The chloride mass-balance method was used to estimate recharge rates at different sites representing the three groundwater basins of the Mountain Aquifer in the West Bank. The recharge rate for the Eastern Basin was calculated as between 130.8 and 269.7 mm/year, with a total average replenishment volume of 290.3 × 106 m3/year. For the Northeastern Basin, the calculated recharge rate ranged between 95.2 and 269.7 mm/year, with a total average recharge volume of 138.5 × 106 m3/year. Finally, the recharge rate for the Western Basin was between 122.6 and 323.6 mm/year, with a total average recharge volume of 324.9 × 106 m3/year. The data reveal a replenishment potential within the estimated replenishment volumes of previous studies for the same area. Also, the range was between 15 and 50% of total rainfall, which is still within the range of previous studies. The geological structure and the climate conditions of the western slope were clearly play an important role in the increment of total volume. In some cases, such as the geological formations in the Northeastern Basin, the interaction between Eocene and Senonian chalk formations result in minimum recharge rates.

Citation Marei, A., Khayat, S., Weise, S., Ghannam, S., Sbaih, M. & Geyer, S. (2010) Estimating groundwater recharge using the chloride mass-balance method in the West Bank, Palestine. Hydrol. Sci. J. 55(5), 780–791.  相似文献   

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