南汇东滩圈围工程对长江口河势影响的数值模拟分析

基于验证的MIKE21软件长江口二维潮流数值模型,计算和重点分析了南汇东滩促淤圈围工程对长江口南槽、北槽和横沙通道的影响。结果表明:南汇东滩促淤圈围工程束窄了南槽下段河道,较大幅度地减小了该段的潮流量;但南槽中段以下河段流速增加幅度较大,河槽将会刷深,河势将得到发展;江亚北槽将会得到发展,北槽中段泥沙淤积现象将会加剧;横沙通道涨落潮流量大幅减少,横沙通道涨落潮流量与南槽涨落潮流量存在非常高的相关性,这对横沙通道作为航道开发和利用会带来较为不利的影响。     

二维水质模型在武汉东湖引水工程中的应用

以"大东湖生态水网"工程的实施为契机,应用MIKE21软件对武汉东湖引水工程进行数值模拟.利用东湖2008年6月和7月实测的水深、TN和TP数据率定了模型参数(床底摩擦力和涡粘系数),并利用2010年7月实测数据建立水动力学模型和对流扩散模型,模拟了四种引水工况下模型运行35 d之后东湖水体中TN、TP浓度分布情况,并比较四种工况的模拟结果.结果表明:在设置两个引水口以及考虑风速影响的情况下,东湖水体中TN、TP浓度分布最均匀.对"大东湖生态水网"工程的实施具有一定的指导意义.     

Assessing hydrological model predictive uncertainty using stochastically generated geological models

In distributed and coupled surface water–groundwater modelling, the uncertainty from the geological structure is unaccounted for if only one deterministic geological model is used. In the present study, the geological structural uncertainty is represented by multiple, stochastically generated geological models, which are used to develop hydrological model ensembles for the Norsminde catchment in Denmark. The geological models have been constructed using two types of field data, airborne geophysical data and borehole well log data. The use of airborne geophysical data in constructing stochastic geological models and followed by the application of such models to assess hydrological simulation uncertainty for both surface water and groundwater have not been previously studied. The results show that the hydrological ensemble based on geophysical data has a lower level of simulation uncertainty, but the ensemble based on borehole data is able to encapsulate more observation points for stream discharge simulation. The groundwater simulations are in general more sensitive to the changes in the geological structure than the stream discharge simulations, and in the deeper groundwater layers, there are larger variations between simulations within an ensemble than in the upper layers. The relationship between hydrological prediction uncertainties measured as the spread within the hydrological ensembles and the spatial aggregation scale of simulation results has been analysed using a representative elementary scale concept. The results show a clear increase of prediction uncertainty as the spatial scale decreases. Copyright © 2015 John Wiley & Sons, Ltd.     

Impacts of environmental stressors on the water resources of intensively managed hydrologic systems

Watersheds are complex systems due to their surface and subsurface spatially connected water fluxes and biochemical processes that shape Earth's critical zone. In intensively managed landscapes, the implementation of watershed management practices (WMPs) regulate their short‐term responses, whereas climate variability controls the long‐term processes. Understanding their responses to anthropogenic and natural stressors requires a holistic approach that takes into account their multiscale spatio‐temporal linkages. The objective of this study was to simulate the impacts of spatially and temporally varying WMPs and projected climate changes on the surface and groundwater resources in the Upper Sangamon River Basin (USRB), a watershed in central Illinois greatly impacted by agricultural and industrial operations. The physically based hydrologic model MIKE‐SHE was used to simulate the hydrologic responses of the basin to different WMPs and climatic conditions. The simulation of a WMP was varied spatially across the basin to determine the spectrum of responses and critical conditions. In general, the wetlands and forested riparian buffer scenarios were found to cause a reduction in the average streamflow, whereas crop rotation had varied responses depending on the location of implementation and the climate condition assumed. Reductions of up to 30% in the average streamflow were found for the forested riparian buffer under the ESM 2M climate projections, whereas an increase of up to 13% with the crop rotation schemes under CM3 climate was predicted. The model results showed that the installation of tile drains across the USRB increased the water table depth (from ground level) by up to 56%, making crop production possible. Groundwater level in USRB appeared to be more sensitive to future climatic conditions than to WMP implementation. The impacts of WMPs are determined to depend on the climate conditions under which they are applied. Investigating individual and combined stressors' effects over the critical zone at a watershed scale can lead to a more comprehensive analysis of the risk and trade‐offs in every managerial decision that will enable an efficient use of resources.     

塔里木河中上游土地利用变化的径流响应

为了定量分析塔里木河中上游土地利用变化对径流的影响程度,基于塔里木河流域1980-2015年土地利用数据及相关水文系列资料,利用MIKE SHE分布式水文模型客观模拟评价了流域中上游土地利用变化下的水文响应过程。结果表明：MIKE SHE模型可以较好的模拟塔里木河流域中上游的日流量过程,在研究区具有良好的适用性;1980-2015年间流域土地利用变化导致流域地表日径流量减少了4.2 m³·s^-1。通过仿真模拟分析草地、林地、耕地三种土地利用情景,得到日均流量分别为147.56 m³·s^-1、141.80 m³·s^-1,144.72 m³·s^-1由此可见,该流域径流对不同土地利用类型的响应差异较大,产流量的总体趋势为草地>耕地>林地。研究成果对于流域土地利用格局的合理规划及极端水文事件的控制具有重要意义。     

Effect of potential evapotranspiration estimates on effective parameters and performance of the MIKE SHE-code applied to a medium-size catchment

The effect of the method of calculating a time series of crop potential evapotranspiration (ET_p) on both the model performance and the magnitude of the main effective parameters of a distributed hydrological model was assessed on the basis of an independent multi-calibration. The ET_p was estimated as a function of the reference evapotranspiration (ET_o) by means of a crop coefficient approach. Three methods for deriving ET_o estimates were used in modelling a medium size catchment in Belgium: (A) Food and Agriculture Organisation (FAO) FAO-24 standard approach; (B) FAO-24 approach but used with coefficients, for both the wind and the Stefan-Boltzmann equations, differing from the standard formulation; and (C) FAO-56 standard approach. For assessing the performance of the estimation approaches, the point scale ET_o outputs of the generation methods were compared to local point scale ET_o guidelines derived from previous research. The outputs of generation method B and of the generation method C showed a close agreement with the local point scale ET_o guidelines. Their effect (to a catchment scale) on the performance of the hydrological model also seemed to be comparable. The best model performance was obtained by using the higher ET_o data generated by method A. The research also revealed a significant dependency of some of the effective parameters on the different ET_p estimates; especially of those parameters related to the computation of the actual evapotranspiration (ET_act).     

Flood forecasting and analysis within the Ulus Basin, Turkey, using geographic information systems

Floods have been the most severe natural disasters in the West Black Sea Region of Turkey for many years; therefore Ulus Basin is selected as a study area for a thorough hydrologic flood analysis. The lack of embankments around the Ulus River and careless changes to the riverbed made by villagers, resulted in major flood events in the basin, causing significant damage in the area. In this study, the hydrodynamic characteristics of the basin and the riverbed are determined by calibrating the hydraulic module of the MIKE 11 modeling system with the observed 1991 flood. Then, for the 25-, 50- and 100-year floods the highest water levels in the river are forecasted by integration of the MIKE 11 hydrologic and hydraulic modules. Afterwards, inundation maps are obtained by using together the hydraulic and GIS modules of the MIKE 11 system.     

厦门港刘五店航道海域溢油扩散数值模拟

利用MIKE 21 HD模块建立了厦门湾二维水动力模型,经2008年最新实测资料,验证了模型的可靠性和适用性,模拟结果为厦门湾刘五店航道二维溢油模型的建立提供水动力基础数据.利用MIKE21 SA模块建立厦门湾刘五店航道二维溢油模型,应用"油粒子"模型模拟输移、风化和热量迁移等过程,对刘五店航道一期工程溢油泄露事故进行...