基于GIS的数字化水文过程模拟研究

在传统水文模型中，一般只能通过降水、蒸发、下渗、气温的输入模拟流量的变化，流域下垫面因素对径流的影响在径流模型中视为“灰箱”。地理信息系统技术的引入。把地面空间特性数字化。利用地形图。土壤分布图、土地利用图、土湿等资料模拟下垫面的地质地貌，把河道、流域的土壤植被等地理因素数字化应用到产汇流理论中。“灰箱”变为“白箱”。为流域研究提供了一种新的思维方法。     

我国燃油税改革效应模拟分析

经历了十几年的讨论,燃油税改革方案终于在2009年出台并实施,改革后燃油税究竟会对我国宏观经济及各部门产生怎样的影响,倍受关注.基于此背景,采用环境CGE模型对改革前后的两种不同燃油税税率进行了量化分析,总体研究得出：从长期发展来看,燃油税改革有利于我国经济结构调整,减少能源消耗和降低碳排放;短期内会增加企业生产成本,抑制宏观经济增长,其中交通运输业和石油加工业受到的冲击最大,应引起有关部门重视.     

城市环境水文问题分析

城市化对水环境污染是一个具有普遍性和严重性的问题.城市水环境污染分为点污染和面污染两类.本文针对城市降雨径流污染(城市面源污染)作了系统分析.其内容包括城市化对降雨径流的影响,城市面污染的积累和暴雨径流的冲刷,以及推求城市暴雨径流污染负荷过程的模拟途径.     

袋式除尘器气流组织的数值模拟分析

文章通过采用流体动力学CFD软件对袋式除尘器中单元模块的除尘空间气流组织进行数值模拟分析，给出了不同位置的布袋不同高度上的气流速度图，将模拟结果与实际工程运行情况进行对比，分析了其可靠性，为袋式除尘器的改进和设计提供了理论依据。     

离心风机数值模拟及气动噪声分析

文章提出了一种基于关键噪声源抗压强度转变层次对离心风机开展降噪的简单方法,根据对离心风机气动式噪声造成原因和散播原理的研究,为离心风机气动式噪声的调节过程及预测分析提供了参考。     

室内模拟麦秆还田引水整地期间水质变化分析

秸秆还田是秸秆综合利用的主要方式,源头上抑制了秸秆焚烧,有效降低了对大气的污染.还田秸秆在微生物降解下释放有机物、氮、磷等至水中,秸秆还田水对地表水环境质量构成潜在威胁.通过室内浸泡麦秆还田土,模拟麦秆还田引水整地,监测5d内水样7项指标,分析水质各指标变化规律,综合讨论了各指标不同变化规律背后的原因,针对降低秸秆还田...     

基于声学模拟分析的大型火电厂降噪技术应用

通常情况下,电厂厂界噪声超标并非是由于单一的某个设备设施导致的,而是多种声源叠加贡献所致,简单的技术方法很难筛选出哪些噪声源是起主要超标贡献作用的,因而需要对全厂噪声源进行系统性的采集监测,借助声学仿真软件进行全厂噪声模拟分析,分析出每个厂界监测点的噪声来源,进而采取合理、有针对性地噪声治理措施。     

成都市可持续发展测度与分析

生态足迹是一种定量测量人类对自然利用程度的方法，已经被广泛应用于定量测度区域或城市的可持续发展。成都地处我国西部，是西部大开发的战略高地和“桥头堡”，对西部地区的发展起着示范、先导、辐射和带动作用。采用生态足迹理论和计算模型对成都市各类土地面积进行量化，具体计算出成都市的生态承载力、供需结构。计算结果表明，2003年其人均生态足迹超过了它的人均生态承载力，生态经济系统存在生态赤字，必须采取措施提高生态承载力，减少生态压力，探讨可持续发展的道路。     

大电流负载引起模拟开关异常现象的机理分析

模拟开关作为对模拟信号进行指定路径传输和控制的单片集成电路,其在整机集成系统的信号采集、过程控制等功能实现中起着不可或缺的作用.传统模拟开关在产品的设计及应用过程当中通常都认为负载电流较小,文章运用实际案例,对大电流负载引起模拟开关器件使用异常现象进行了机理分析与定位,提出了可有效解决该异常现象的可行措施.     

成都市径流污染的概念性模型

概念性模型是根据城市径流形成过程及对水体影响变化的物理机理建立的一套数学模型，模型及参数均有明确的物理意义。本文用概念性模型求出了成都市街道地表物的累积量，降雨径流污染负荷量，并模拟了污染物对受纳水体的影响。     

Effects of Impervious Area and BMP Implementation and Design on Storm Runoff and Water Quality in Eight Small Watersheds

The effects of increases in effective impervious area (EIA) and the implementation of water quality protection designed detention pond best management practices (BMPs) on storm runoff and stormwater quality were assessed in Gwinnett County, Georgia, for the period 2001‐2008. Trends among eight small watersheds were compared, using a time trend study design. Significant trends were detected in three storm hydrologic metrics and in five water quality constituents that were adjusted for variability in storm characteristics and climate. Trends in EIA ranged from 0.10 to 1.35, and changes in EIA treated by BMPs ranged from 0.19 to 1.32; both expressed in units of percentage of drainage area per year. Trend relations indicated that for every 1% increase in watershed EIA, about 2.6, 1.1, and 1.5% increases in EIA treated by BMPs would be required to counteract the effects of EIA added to the watersheds on peak streamflow, stormwater yield, and storm streamflow runoff, respectively. Relations between trends in EIA, BMP implementation, and water quality were counterintuitive. This may be the result of (1) changes in constituent inputs in the watersheds, especially downstream of areas treated by BMPs; (2) BMPs may have increased the duration of stormflow that results in downstream channel erosion; and/or (3) spurious relationships between increases in EIA, BMP implementation, and constituent inputs with development rates.     

Reduction of Urban Runoff Through Economic Incentives: Boulder,Colorado1

ABSTRACT: The problems of increased surface runoff which follow in step with urbanization can be conceptualized in terms of environmental economics. The private transformation of land from a permeable to an impermeable surface imposes the externality of increased surface runoff upon society as a whole and especially on those downstream. The city of Boulder, Colorado, has enacted an ordinance which attempts to internalize some of these external costs and at the same time decrease surface runoff from the urban environment.     

Stream and Retention Pond Thermal Response to Heated Summer Runoff From Urban Impervious Surfaces1

Abstract: Runoff from parking lots during summer storms injects surges of hot water into receiving water bodies. We present temperature data collected near urban storm sewer outfalls in Blacksburg, Virginia, using arrays of sensors in a stream and a stormwater pond. Surges occurred roughly a dozen times per month, ranging up to 8.1°C with average duration 2 h in the stream and up to 11.2°C with average duration 7 h in the pond. Surges were larger in the pond due to a larger contributing watershed, no dilution by upstream water, and cool background temperatures near the outfall. Surges began abruptly, warming at rates averaging 0.2°C/min for periods of 5‐20 min. Surges dissipated as they propagated into the water bodies, travelling further in the stream (>19 m) than the pond (～10 m) consistent with greater advection in the stream. Surges were largest and most frequent in the afternoon but occurred at all times of day and night. Stream surges exhibited two phases: an early high‐temperature low‐volume input from the storm sewer and a later low‐temperature high‐volume input from upstream. Surges at the pond did not exhibit two phases, consistent with inputs only from storm sewers. Surges are likely common in urban areas, and may cumulatively have consequences for aquatic organisms, biogeochemical process rates, and even human health. Such effects may be compounded by urban heat islands and climate change, so prevention or mitigation should be considered.     

Runoff Simulation of the Headwaters of the Yellow River Using The SWAT Model With Three Snowmelt Algorithms1

Abstract: The Soil and Water Assessment Tool (SWAT) model combined with different snowmelt algorithms was evaluated for runoff simulation of an 114,345 km² mountainous river basin (the headwaters of the Yellow River), where snowmelt is a significant process. The three snowmelt algorithms incorporated into SWAT were as follows: (1) the temperature‐index, (2) the temperature‐index plus elevation band, and (3) the energy budget based SNOW17. The SNOW17 is more complex than the temperature‐based snowmelt algorithms, and requires more detailed meteorological and topographical inputs. In order to apply the SNOW17 in the SWAT framework, SWAT was modified to operate at the pixel scale rather than the normal Hydrologic Response Unit scale. The three snowmelt algorithms were evaluated under two parameter scenarios, the default and the calibrated parameters scenarios. Under the default parameters scenario, the parameter values were determined based on a review of the current literature. The purpose of this type of evaluation was to assess the applicability of SWAT in ungauged basins, where there is little observed data available for calibration. Under the calibrated parameters scenario, the parameters were calibrated using an automatic calibration program, the Shuffled Complex Evolution (SCE‐UA). The purpose of this type of evaluation was to assess the applicability of SWAT in gauged basins. Two time periods (1975‐1985 and 1986‐1990) of monthly runoff data were used in this study to evaluate the performance of SWAT with different snowmelt algorithms. Under the default parameters scenario, the SWAT model with complex energy budget based SNOW17 performed the best for both time periods. Under the calibrated parameters scenario, the parameters were calibrated using monthly runoff from 1975‐1985 and validated using monthly runoff from 1986‐1990. After parameter calibration, the performance of SWAT with the three snowmelt algorithms was improved from the default parameters scenario. Further, the SWAT model with temperature‐index plus elevation band performed as well as the SWAT model with SNOW17. The SWAT model with temperature‐index algorithm performed the poorest for both time periods under both scenarios. Therefore, it is suggested that the SNOW17 model be used for modeling ungauged basins; however, for gauged basins, the SNOW17 and simple temperature‐index plus elevation band models could provide almost equally good runoff simulation results.     

Incorporating Variable Source Area Hydrology into a Spatially Distributed Direct Runoff Model1

Buchanan, Brian, Zachary M. Easton, Rebecca Schneider, and M. Todd Walter, 2011. Incorporating Variable Source Area Hydrology Into a Spatially Distributed Direct Runoff Model. Journal of the American Water Resources Association (JAWRA) 48(1): 43‐60. DOI: 10.1111/j.1752‐1688.2011.00594.x Abstract: Few hydrologic models simulate both variable source area (VSA) hydrology, and runoff‐routing at high enough spatial resolutions to capture fine‐scale hydrologic pathways connecting VSA to the stream network. This paper describes a geographic information system‐based operational model that simulates the spatio‐temporal dynamics of VSA runoff generation and distributed runoff‐routing, including through complex artificial drainage networks. The model combines the Natural Resource Conservation Service’s Curve Number (CN) equation for estimating storm runoff with the topographic index concept for predicting the locations of VSA and a runoff‐routing algorithm into a new spatially distributed direct hydrograph (SDDH) model (SDDH‐VSA). Using a small agricultural watershed in central New York, SDDH‐VSA results were compared to those from a SDDH model using the traditional land use assumptions for the CN (SDDH‐CN). The SDDH‐VSA model generally agreed better with observed discharge than the SDDH‐CN model (average, Nash‐Sutcliffe efficiency of 0.69 vs. 0.58, respectively) and resulted in more realistic spatial patterns of runoff‐generating areas. The SDDH approach did not correctly capture the timing of runoff from small storms in dry periods. Despite this type of limitation, SDDH‐VSA extends the applicability of the SDDH technique to VSA conditions, providing a basis for new tools to help identify critical management areas and assess water quality risks due to landscape alterations.     

三峡库区中小城镇城市降雨径流污染特征及现状研究

本研究采用从微观到宏观，在库区沿岸城镇诸多相关因素相似前提下，选择涪陵市为典型试验区；从水文因素，街道地表物累积冲刷规律研究着手，建立累积、冲刷计算模式，计算出涪陵市年降雨径流污染负荷和库区污染荷载因子，同时选择具有代表性的集水闭合小区进行水质、水量同步观测试验进行验证；确定外推因子，计算三峡库区城市降雨径流年冲刷入长江的总固体，ＳＳ，ＢＯＤ５，ＣＯＤ，Ｔ－Ｎ，Ｔ－Ｐ３量分别为５３９６８吨，３８０     

Migration Pathways and Remediation of Urban Runoff for PAH Control

The migration pathways for polyaromatic hydrocarbons (PAH) and the associated active attenuating mechanisms within the urban environment are examined. The interest in developing an improved understanding of PAH migration/attenuation is focused toward quantification of the cost-effectiveness of urban runoff control strategies for mitigation of PAH inputs to receiving water bodies.A case study application to the City of Sault Ste Marie demonstrates that snow removal from sub-basins with the largest deposition rates, and relatively small wet and/or dry stormwater management ponds, are the most cost-effective remediation strategies.     

Mechanistic Simulation of Tree Effects in an Urban Water Balance Model1

Abstract: A semidistributed, physical‐based Urban Forest Effects – Hydrology (UFORE‐Hydro) model was created to simulate and study tree effects on urban hydrology and guide management of urban runoff at the catchment scale. The model simulates hydrological processes of precipitation, interception, evaporation, infiltration, and runoff using data inputs of weather, elevation, and land cover along with nine channel, soil, and vegetation parameters. Weather data are pre‐processed by UFORE using Penman‐Monteith equations to provide potential evaporation terms for open water and vegetation. Canopy interception algorithms modified established routines to better account for variable density urban trees, short vegetation, and seasonal growth phenology. Actual evaporation algorithms allocate potential energy between leaf surface storage and transpiration from soil storage. Infiltration algorithms use a variable rain rate Green‐Ampt formulation and handle both infiltration excess and saturation excess ponding and runoff. Stream discharge is the sum of surface runoff and TOPMODEL‐based subsurface flow equations. Automated calibration routines that use observed discharge has been coupled to the model. Once calibrated, the model can examine how alternative tree management schemes impact urban runoff. UFORE‐Hydro model testing in the urban Dead Run catchment of Baltimore, Maryland, illustrated how trees significantly reduce runoff for low intensity and short duration precipitation events.