Simulation Modeling of Runoff,Groundwater Flow and Sediment Transport into Kastoria Lake,Greece

Kastoria Lake is located in northwestern Greece. The whole basin of the lake is about 253 km². For the computation of the surface water volume inflowing into the lake from the main streams of the sub-basins located around Kastoria Lake, a rainfall-runoff sub-model is used. A quasi-three-dimensional simulation model of the Kastoria basin aquifer is also realized, in order to estimate the groundwater contribution to the volumetric budget of the lake and the whole basin as well. For the computation of sediment load inflowing into the lake from the main streams of the sub-basins, the rainfall-runoff sub-model is combinedwith a soil erosion sub-model and a sediment transport sub-model for streams. A GIS was developed in the hydrologic basin with all data needed for parameter identification and model application. The data base was enriched by a series of on site measurements of water discharge made in all main streams for one whole hydrologic year. By means of the resulting mathematical sediment model, those sub-basins, which deliver most sediment load to the lake, are identified. On the basis of this identification, a series of control measures, for the reduction of sediment inflowing into the lake, at certain places of the above mentioned sub-basins is proposed.     

GIS支持下的凡河流域农业非点源污染物时空特征分析

为了解铁岭县凡河流域农业非点源污染现状,本文以铁岭县多年乡镇统计报表为基础,结合输出系数法及源强系数法分析了凡河流域2007-2009年四种农业非点源污染物排放量及其排放强度的时空分布特征。结果表明:(1)流域内农业非点源污染物排放总量呈持续上升趋势,总氮、总磷、化学需氧量及氨氮的平均排放量为3174.5、361.4、16624.5和3980.3t/a;(2)流域内主要污染物为化学需氧量,主要污染源为畜禽养殖;(3)污染物排放总量及强度空间上大致呈中、西部高,东部低的特点,李千户乡及铁岭市区为主要污染区域。为有效地控制凡河流域农业非点源污染,当地政府应把重点放在畜禽粪便及居民生活垃圾的处理方式上。     

分形油气藏非达西低速渗流时续流和表皮效应的影响

本文建立了分形油气藏非达西低速渗流时续流和表皮效应影响的数学模型，并对定解问题用拉普拉斯变换求解，拉氏空间的特解用格林函数表示，得到了解析解和渐近解。     

Field Application of the Multilinear Muskingum Discharge Routing Method

To implicitly model the nonlinear dynamics of flood wave propagation in rivers with floodplains, a multilinear discharge-hydrograph routing method based on time distribution scheme is proposed. The framework of this method is based on the variable parameter Muskingum-type routing method, which is used as the linear sub-model. The applicability limit and suitability of this flood routing method is verified using numerical experiments and field data, respectively.     

率水流域非点源污染分析及施肥措施模拟

率水流域周边农业用地施用的大量化肥为流域内非点源负荷主要来源之一,研究该流域内不同施肥措施对其下游千岛湖水体中氮磷污染控制具有重要意义。通过搭建率水流域SWAT模型,设置化肥减量,粪肥替代和深层施肥3种施肥情景,探究其对流域非点源污染输出的响应特征。结果表明:化肥减量50%可减少约9. 77%的总氮负荷和4. 42%的总磷负荷,粪肥替代化肥对于氮磷负荷的削减率较低,深层施肥的总氮负荷削减率远低于总磷,化肥减量和深层施肥联合措施可分别降低10. 11%和3. 38%的总氮、总磷负荷,即为流域内施肥措施的最佳方案,同时基于SWAT模型的施肥情景模拟对削减流域非点源污染具有参考意义。     

Assessment of point and non-point pollution associated with the power generation sector in South Africa.

Access to water and water availability remains a key factor in ensuring the sustainability of development in Southern Africa. The need for guidelines to improve management of this valuable resource, and to regulate pollutant discharge, is therefore of national interest. A new and growing threat to our natural water resources is non-point source (NPS) pollution. The important distinction between point pollution and NPS pollution is that the latter is difficult to identify and the entry point of contamination to resources is diffuse and not limited to a single location. NPS pollution associated with power generation includes, but is not limited to, atmospheric deposition resulting from emissions (air and water), leachate from coal storage piles and runoff from impervious areas which are covered with dust fallout from coal and ash handling operations. Emissions of primary concern are sulfur, nitrogen and mercury.     

多沙河流中石油类污染物迁移的一维数学模型Ⅰ.吸附模型

本文研究了黄土高原丘陵区域径流受石油类污染的两种过程和与之相对应的两种模型，根据石油类污染物污染过程特点和延河水文与径流特点及流域自然地理特征，建立了一维多沙河流中石油类污染物的吸附模型。模型中主要考虑了河流悬移质、推移质泥沙和底泥与石油类的相互作用以及河流的弥散作用对石油类迁移的影响。运用拉普拉斯变换得到了模型的解析解。由室内静态和动态试验，确定模型中各参数；并分析了几个主要参数变化对模拟结果的影响。运用实测资料对模型进行了验证，并根据延安环保局监测资料预测分析了两个典型的石油类污染源排污对水体的影响。预测结果表明：在15min内两污染源分别造成了600m和500m的石油类污染带。     

多污染源随机排污的水质影响分析方法及其应用

针对污水排放特征,将污染源分为连续排放型污染源和间隙排放型污染源。对连续排放型污染源,采用确定性方法定义污染源强;而对于间隙排放型污染源,运用不确定性理论,根据其排放污染源的随机统计特征,对污染源进行随机概化。将不确定性理论应用于多污染源随机排污对环境水体的水质影响分析,给出了基于不确定性理论的水质影响预测方法,建立了二维随机水质数学模型。并将该方法应用于某市水源地水质影响的随机分析,得到了在多污染源随机排放协同影响下水质浓度随机变化的统计特征。     

Modeling and Management of Urban Stormwater Runoff Quality: A Review

Nonpoint source (NPS) pollution from urban runoff has been established as a major cause of receiving water degradation. In an effort to control this problem, new regulations have been passed in the U.S.A. and federal, state, and local agencies are devising urban runoff management programs. This paper reviews recent regulations and studies related to urban stormwater runoff control and planning in the U.S.A.; discusses fundamentals of urban NPS pollution including transport processes and types and sources of pollutants; reviews current hydrologic and water quality mathematical models used in the U.S.A.; presents case studies in both modeling and management; and describes fundamentals of Best Management Practices (BMPs) in urban runoff control. Finally, it summarizes future research needs.     

THE FLOW ANALYSIS OF FLUIDS IN FRACTAL RESERVOIR WITH THE FRACTIONAL DERIVATIVE

1. INTRODUCTION Chang and Yortsos [1 ]presented the theoretical model for infinite fractal reservoir. Acuna et al. [ 2]explained the fractal characteristic of a naturally fractured geothermal field. Acuna [ 3] reviewed the theoretical background of fractal analysis. They alsodemonstrated the application of various diagnostic techniques for fractal pressure transient analysis as developed by Chang and Yortsos [1 ].Tong[4 ? 7]give the analytical solution of various cases for transient flow…     

非点源污染研究综述

与点源污染相比,非点源污染具有随机性、广泛性、滞后性等特点,其在机理研究和模型模拟上都更加复杂.本文首先对非点源污染的基本概念、特征及其对水环境的影响做了简要的介绍;然后分别从降雨径流、土壤侵蚀和非点源污染物迁移转化非点源污染发生的3个重要环节对其研究发展历史及现状进行了概述,并介绍了非点源污染研究与GIS和RS技术的...     

A Diagnostic Decision Support System for BMP Selection in Small Urban Watershed

Best Management Practices (BMPs) have become the most effective way to mitigate non-point source pollution (NPS) issues. Much attention has been paid to NPS in rural areas, where agricultural activities increase nutrients, toxics, and sediments in surface water. Stormwater from urban areas is also a major contributor to NPS pollution. For watersheds bearing various soil types and land uses, a single type of BMP cannot be the panacea to all stormwater problems. To solve these problems, a Diagnostic Decision Support System (DDSS) was developed in this research. The DDSS can identify and locate the most critical NPS areas (hotspots) within a watershed in high spatial resolution. The DDSS can provide a series of spatially distributed small-scale BMPs which are effective in treating the NPS and are suitable for the physical environment. The BMPs, varying in types and locations, are recommended at HRU (Hydrologic Response Unit) level. The DDSS was tested in Watts Branch, a small urban watershed of the Anacostia River in metropolitan Washington D.C., USA. The process-based hydrologic model, Soil and Water Assessment Tool (SWAT), was used to simulate watershed responses. The simulation results were then used by the DDSS for BMP recommendation. Hotspots of different NPS were successfully located and prescribed with spatially distributed BMPs. The DDSS serves as a useful tool to better understand urban watersheds and to make proper stormwater management plans.     

离散广义Nash汇流模型及其在河道洪水演算中的应用

基于广义Nash汇流理论,通过定义S曲线或滞蓄曲线,简化了广义Nash汇流计算公式,并推导得出了离散广义Nash汇流模型,将河道下断面出流过程表述为时段初、末入流量与当前时刻及之前若干时刻出流量的线性组合,权重系数由S曲线或滞蓄曲线得出。该模型物理概念明确,又有一定统计意义,结构简单,形式直观,便于在实际中推广应用,最后通过实例分析检验了模型的预报能力。     

多沙河流中石油类污染物迁移的一维数学模型(Ⅱ-解吸模型)

本文建立了一维河流石油类污染物“解吸为主”的动态水质模型。模型方程中考虑了河流悬移质、推移质泥沙和底泥与石油类之间发生的吸附\解吸的动态过程，以及河流弥散作用对石油类污染物在多沙河流中迁移的影响。模型还考虑了底泥解吸与泥沙解析在速率上的差别，使模型更加精确实用。运用拉普拉斯变换，求得了模型方程法的解析解。用室内烧杯试验的方法确定出了研究区域内的污染底泥解吸常数kdw；结合室内水槽动态试验，对解吸模型进行了验证。结果表明，该模型能够较好地描述一维多沙河流污染沉积物中石油类污染物的解吸过程。     

SWAT模型在流域LUCC水文效应研究中的应用

土地利用/覆被变化（LUCC）的水文效应是GLP研究的热点。分布式水文模型SWAT是目前被广泛应用于LUCC水文效应研究的水文模型之一。论文首先概述了SWAT模型的发展历程和最新版本SWAT 2005的功能,其次就模型在不同土地覆被条件下水文效应应用中的几个方面进行了总结和分析：流域径流模拟,区域水量平衡分析和非点源污染的模拟及其对BMP评价研究的贡献。最后,归纳探讨模型应用中存在的一些问题,通过合理的情境设计以及关键参数的实测等方法,可以实现模型在流域LUCC水文效应研究中的高效应用。     

Design and Application of an Adaptive Time Delay Model for Flow Routing in Prismatic Trapezoidal Geometry River Reach

Simplified flow routing model is favourably used for control-based application because it does not only present acceptable results but also is computationally inexpensive. Recently, the Time Delay model (TD) with two parameters, time constant and time delay has been developed in order to approximate the river flow in a very wide rectangular profile. This paper presents an advancement we thereafter call Adaptive Time Delay model (ATD) that expands the application scope of the TD Model by simulating the flow using a prismatic trapezoidal geometry. Firstly, the mathematical representation of the ATD model and the linearized Saint Venant model (SVE) are defined. Secondly, the transfer functions of the ATD model and the complex hydraulic model (SVE) are obtained by Laplace transformation. Finally, the Taylor expansion technique is used to find cumulants of the two transfer functions, and consequently equating the cumulants to derive time constant and time delay of the ATD model as functions of the complex hydraulic model parameters. By applying the fourth order Runge Kutta numerical scheme the flow rate and water level at downstream reach end are simulated. The innovation of this research is that both water stage and flow rate are derived through optimization. The performance of the ATD Model is also presented and compared to the TD Model in a case study. The extension of the time delay model does not only issue more accurate results but also introduces more outcomes like flow rate, and relation curves between time delay and time constant with discharge that might be useful in flood forecasting and other purposes in water resources operation.     

太湖地区农村面源污染控制技术与对策

通过对太湖地区农村面源污染主要特征的分析，初步估算了主要面源污染负荷的贡献率，提出了控制太湖地区农村面源污染的总体思路与设想，提供了农村生活污水、生活垃圾、农田氮、磷损失、村镇地表径流污染的控制技术，以及污染河道的生态修复技术。与此同时，还讨论了农村面源污染的管理对策、管理模式与相关政策法规等，可为农村面源污染的控制、农村生态与环境的改善提供借鉴。     

基于GIS和SWAT模型的清江流域面源污染模拟研究

 水体面源污染评价研究是一项复杂的工作,涉及面广和要求有较长时间序列的数据。面源污染模型很大程度上依赖于对于流域的特征描述的相关参数,因此提高输入模型参数的精度,有利于提升流域面源污染的径流、泥沙和营养物质的产出模拟效果。GIS和面源污染模型的有机结合是当前面源污染模拟研究最有效的方法。本研究建立了基于GIS的基础数据库,其中包括DEM、土壤类型、土地利用、气象数据以及农业耕作管理数据等。面源污染模拟的产生和形成具有很大的不确定性,这更加增加了监测和控制面源污染的难度。探索影响面源污染的主要因素,研究其不确定性对于提出和制定污染控制措施至关重要。本研究进行了清江流域面源污染的参数敏感性分析,根据观测数据对SWAT模型进行验证和率定,并利用SWAT模型进行模拟,揭示了清江流域面源污染的时空分布特征,确定了清江流域水土流失风险区。结果表明清江流域的面源污染主要发生在丰水期,不同的土地利用方式、农业耕作制度以及降水等是影响径流量和营养物质产生的主要因素。     

基于空间信息技术的新农村建设面源污染动态监控

面源污染的调控与治理是关系到新农村建设和社会可持续发展的重要问题。将 RS , GIS 和 GPS 技术引入农业面源污染研究领域,通过建立完善的农业面源污染监测系统,可以有效地实施对环境污染的动态监测,科学管理具有空间属性的各种农业环境面源污染信息。以空间信息技术为基础的监测信息系统能够为农业面源污染及农村环境治理提供可靠有效的辅助决策信息,并为政府及有关部门正确决策提供科学依据。     

SWAT模型及其应用研究

利用数学模型来模拟水文、泥沙、非点源污染过程是流域管理中对特定管理措施的效果进行评估的重要工具,也是研究环境变化条件下水资源管理的重要手段。SWAT（Soil and Water Assessment Tool）模型就是一个集成了遥感（RS）、地理信息系统（GIS）和数字高程模型（DEM）技术的目前国际流行的分布式水文模拟工具。该文介绍了SWAT模型的发展历程、原理及特点,概述了SWAT模型目前在径流模拟、非点源污染模拟与控制、气候变化对水文响应的影响、模型参数敏感性分析方面的进展情况,并对SWAT模型今后的应用和改进做了初步探讨。