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Clay‐settling areas (CSAs) are one of the most conspicuous and development‐limiting landforms remaining after phosphate mining. Many questions are asked by the mining and regulatory communities with regard to the correct modelling (predictive) methods and assumptions that should be used to yield viable hydrologic post‐reclamation landforms within CSAs. Questions as to the correct methodology to use in modelling/predicting long‐term CSA hydrologic performance have historically been difficult to answer because the data and analysis to support popular hypotheses did not exist. The goal of this paper was to substantially improve the data, analysis and predictive methodology necessary to return CSAs to viable hydrologic units, and moreover, to develop better understanding of the hydrology of CSAs and their ability to support wetlands. The study site is located at the Fort Meade Mine in Polk County, Florida. In this paper, continuous model simulation and calibration of study site were conducted for the hydrologic model, Hydrological Simulation Program – FORTRAN, which was generally selected on the basis of its popularity in predicting the hydrologic behaviour of CSAs. The objective of this study was to simulate streamflow discharges and stage to estimate runoff response from these areas on the basis of the observed rainfall within the CSA. A set of global hydrologic parameters was selected and tested during the calibration by the parameter estimation software PEST. A comparison of the simulated and observed flow data indicates that the model calibration adequately reproduces the hydrologic response of the CSAs. The estimated parameters can be used as references for future application of the model. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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River water temperature is a common target of water quality models at the watershed scale, owing to its principal role in shaping biogeochemical processes and in stream ecology. Usually, models include physically‐based, deterministic formulations to calculate water temperatures from detailed meteorological information, which usually comes from meteorological stations located far from the river reaches. However, alternative empirical approaches have been proposed, that usually depend on air temperature as master variable. This study explored the performance of a semidistributed water quality application modelling river water temperature in a Mediterranean watershed, using three different approaches. First, a deterministic approach was used accounting for the different heat exchange components usually considered in water temperature models. Second, an empirical approximation was applied using the equilibrium temperature concept, assuming a linear relationship with air temperature. And third, a hybrid approach was constructed, in which the temperature equilibrium concept and the deterministic approach were combined. Results showed that the hybrid approach gave the best results, followed by the empirical approximation. The deterministic formulation gave the worst results. The hybrid approach not only fitted daily river water temperatures, but also adequately modelled the daily temperature range (maximum–minimum daily temperature). Other river water features directly dependent on water temperature, such as river intrusion depth in lentic systems (i.e. the depth at which the river inflow plunges to equilibrate density differences with lake water), were also correctly modelled even at hourly time steps. However, results for the different heat fluxes between river and atmosphere were very unrealistic. Although direct evidence of discrepancies between meteorological drivers measured at the meteorological stations and the actual river microclimate was not found, the use of models including empirical or hybrid formulations depending mainly on air temperature is recommended if only meteorological data from locations far from the river reaches are available. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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The temporal‐spatial resolution of input data‐induced uncertainty in a watershed‐based water quality model, Hydrologic Simulation Program‐FORTRAN (HSPF), is investigated in this study. The temporal resolution‐induced uncertainty is described using the coefficient of variation (CV). The CV is found to decrease with decreasing temporal resolution and follow a log‐normal relation with time interval for temperature data while it exhibits a power‐law relation for rainfall data. The temporal‐scale uncertainties in the temperature and rainfall data follow a general extreme value distribution and a Weibull distribution, respectively. The Nash‐Sutcliffe coefficient (NSC) is employed to represent the spatial resolution induced uncertainty. The spatial resolution uncertainty in the dissolved oxygen and nitrate‐nitrogen concentrations simulated using HSPF is observed to follow a general extreme value distribution and a log‐normal distribution, respectively. The probability density functions (PDF) provide new insights into the effect of temporal‐scale and spatial resolution of input data on uncertainties involved in watershed modelling and total maximum daily load calculations. This study exhibits non‐symmetric distributions of uncertainty in water quality modelling, which simplify weather and water quality monitoring and reducing the cost involved in flow and water quality monitoring. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Landslides generate enormous volumes of sediment in mountainous watersheds; however, quantifying the downstream transport of landslide‐derived sediment remains a challenge. Landslide erosion and sediment delivery to the Shihmen Reservoir watershed in Taiwan was estimated using empirical landslide frequency–area and volume–area relationships, empirical landslide runout models, and the Hydrological Simulation Program‐ FORTRAN (HSPF). Landslide erosion rates ranged from 0.4 mm yr‐1 to 2.2 mm yr‐1 during the period 1986–2003, but increased to 7.9 mm yr‐1 following Typhoon Aere in 2004. The percentage of landslide sediment delivered to streams decreased from 78% during the period 1986–1997 to 55% in 2004. Although the delivery ratio was lower, the volume of landslide sediment delivered to streams was 2.81 × 106 Mg yr‐1 in 1986–1997 and 8.60 × 106 Mg yr‐1 in 2004. Model simulations indicate that only a small proportion of the landslide material was delivered downstream. An average of 13% of the landslide material delivered to rivers was moved downstream during the period 1986–1997. In 2004, the period including Typhoon Aere, the annual fluvial sediment yield accounted for approximately 23% of the landslide material delivered to streams. In general, the transfer of sediment in the fluvial system in the Shihmen Reservoir watershed is dominantly transport limited. The imbalance between sediment supply and transport capacity has resulted in a considerable quantity of landslide material remaining in the upper‐stream regions of the watershed. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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参数率定是水文模型构建与应用的重要基础。在多目标水文校准中,不同目标函数的权重设置直接影响校准的结果,如何确定不同目标函数的权重是水文校准的关键问题。选择典型半分布式水文模型HSPF(Hydrological Simulation Program-Fortran),基于PEST多目标校准模型,以牛栏江上游流域为研究对象,研究目标函数权重对HSPF水文模拟拟合优度的影响,为HSPF模型参数自动率定提供指导与借鉴。结果表明:(1)当PEST-HSPF水文校准的单目标函数权重(日流量、月流量、超流天数)上升时,模型的纳什系数和相对偏差呈现非线性变化特征,不规则波动幅度较大;(2)3个目标函数的权重在1~10量级内模型能够获得较高的预测能力和较低的误差,模型的纳什系数平均可达到0.8以上,相对偏差在10%以内;(3)超流量天数权重设置对模型的预测能力变化影响较大,日流量天数权重对相对偏差的波动影响较大,当超流天数的相对权重在1~1 000范围内变化时,模型纳什系数在0.02~0.86之间波动剧烈,当日流量相对权重值超过30时,相对偏差变化明显。 相似文献
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Cross-Media Models of the Chesapeake Bay Watershed and Airshed 总被引：1，自引：0，他引：1
Linker Lewis C. Shenk Gary W. Dennis Robin L. Sweeney Jeffery S. 《Water Quality and Ecosystems Modeling》2000,1(1-4):91-122
A continuous, deterministic watershed model of the Chesapeake Bay watershed, linked to an atmospheric deposition model is used to examine nutrient loads to the Chesapeake Bay under different management scenarios. The Hydrologic Simulation Program - Fortran, Version 11 simulation code is used at an hourly time-step for ten years of simulation in the watershed. The Regional Acid Deposition Model simulates management options in reducing atmospheric deposition of nitrogen. Nutrient loads are summed over daily periods and used for loading a simulation of the Chesapeake estuary employing the Chesapeake Bay Estuary Model Package. Averaged over the ten-year simulation, loads are compared for scenarios under 1985 conditions, forecasted conditions in the year 2000, and estimated conditions under a limit of technology scenario. Limit of technology loads are a 50%, 64%, and 42% reduction from the 1985 loads in total nitrogen, total phosphorus, and total suspended solids, respectively. Urban loads, which include point source, on-site wastewater disposal systems, combined sewer overflows, and nonpoint source loads have the highest flux of nutrient loads to the Chesapeake, followed by crop land uses.on assignment from NOAA Air Resources Laboratory 相似文献
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气候变化和人类活动对信江流域径流影响模拟 总被引：1，自引：0，他引：1
以1960―1990年为基准期、1991―2005年为影响期,使用HSPF（Hydrological Simulation Program-Fortran）水文模型定量分析了影响期气候变化和人类活动对信江流域径流的影响及其各自的贡献率。结果表明：1）相对于1960―1990年,1991―1995、1996―2000年的年平均径流深分别增加了271.9和246.3 mm,2001―2005年的年平均径流深减少64.1 mm。其中,气候变化对径流的影响分量在65.6%~88.0%之间,人类活动对径流的影响分量在12.0%~34.4%之间。2）人类活动对极值流量有影响。在影响期,年最大7 d平均流量和最大15 d平均流量模拟值大于对应的实测极值流量。3）在气候变化因子中,流域降水量的增加,是引起20世纪90年代信江流域径流显著增大的主要原因,其次是蒸发量的下降;人类活动包括植树造林、城市化以及水利工程修建,是影响流域径流变化的次要原因。 相似文献
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降雨变化对东江流域径流的影响模拟分析 总被引：2，自引：1，他引：1
降雨变化对流域水文过程的影响是地理与环境科学领域关注的热点。应用流域水文模型HSPF建立了东江流域的径流模拟模型,并结合日降雨随机模拟模型,分析了降雨的长期变化对流域径流的影响。结果表明,降雨对东江流域的径流影响显著,径流量随降雨量均值与降雨量变差系数的增减而增减;相同的降雨量均值变化幅度条件下,径流增减的变化幅度相近;降雨量变差系数增加对径流的影响大于降雨量变差系数减小的影响,降雨强度的变化是影响径流量的重要因素,降雨量变化剧烈时,产生的径流更多;在同等的变化幅度内,降雨量均值变化对径流量的影响大于降雨量变差系数;由降雨情景变化引起的月径流的变化在6~8月最为明显。 相似文献
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流域非点源污染模拟研究--以滇池流域为例 总被引：18，自引：2，他引：16
流域的水质管理是一个多步骤的过程,数学模型以其定量计算和动态操作在流域管理中起着重要作用。本文利用美国EPA开发的HSPF(HydrologicalSimulationProgramFortran)模型,选取云南滇池流域作为案例,给出非点源污染模型流域水文水质的模拟过程。首先在子流域划分的基础上,完成数据库的建立。参数估值主要依据流域性质、先前经验值、其他模拟研究和文献中的取值。参数优化、模型校正和模拟验证是采用流域河流出口流量和污染物浓度值完成。最后用校正后的模型计算了滇池流域河流入湖流量及各子流域污染总负荷量与非点源污染负荷量。 相似文献