青藏高原生态资产地域划分中的SOFM网络技术

针对目前地域划分中存在的问题,论文尝试以人工神经网络技术作为区划工作的理论支撑,构建了自组织特征映射SOFM网络,以青藏高原环境与生态系统资产作为待分客体,探索了新技术和方法在生态资产地域划分中的应用。结果表明,对于自然界中广泛存在的非线性问题,SOFM网络具有比聚类分析等线性分类器更强的适应性。应用SOFM网络在对待分客体生态资产进行类型划分的基础上,使用策略性循环尺度转换(SCS)范式对其进行了区域转换,最终完成了青藏高原范围内生态资产的地域划分。     

基于“径流-地类”参数的非点源氮磷负荷估算方法

东江作为广东省重要的饮用水源,其上游农业集水区非点源氮磷流失量备受关注.因此,本文以东江上游上莞河小流域为研究区,利用2011年的集水区水质监测数据,在平均浓度法及输出系数法的基础上,构建基于"径流-地类"参数的非点源氮磷负荷计算式,其径流、地类参数分别通过校正后的SCS模型和土地利用现状图获取,并分别对上莞河流域及流域各地类的非点源氮磷流失量进行估算.研究结果表明,汛期上莞河流域氮磷流失量主要来源于非点源污染,其非点源氮、磷流失量分别占氮、磷流失总量的97.32%、98.05%.坡度对流域非点源氮磷流失影响较小,地类是影响非点源氮磷输出的重要因素.构建的计算式能较好地估算非点源氮、磷负荷量,在次暴雨尺度非点源氮、磷输出量模拟精度分别为84.78%、81.06%.2011年度上莞河流域非点源氮、磷输出量分别为48923.4、7189.3 kg,耕地、居民地分别是非点源氮、磷输出的关键源区,其非点源氮、磷输出量分别占流域非点源氮、磷输出总量的84.20%、58.54%.     

垃圾填埋场室内模拟试验注水量确定方法及其应用

针对填埋场室内模拟试验往往忽略降雨径流和初损的问题,提出运用SCS模型确定室内模拟试验日注水量的方法,并将计算结果应用于成都长安填埋场室内模拟试验中.结果表明,采用SCS模型计算所得的日入渗量进行注水的模拟柱渗滤液产量和水质变化能够更准确的模拟填埋场实际情况.     

THE APPLICATION OF HYDROLOGIC MODELS TO SMALL WATERSHEDS HAVING MILD TOPOGRAPHY1

ABSTRACT: The application of hydrologic models to small watersheds of mild topography is not well documented. This study evaluates the applicability of hydrologic models described by Huggins and the Soil Conservation Service to small watersheds by comparing the simulated and actual hydrograph for both gaged and ungaged situations. The annual maximum rainfall events plus storms exceeding 2.5 inches from 25 years of rainfall and runoff data for two small watersheds were selected for the model evaluations. These storms had a variety of patterns and occurred on many different watershed conditions. Simulated and actual hydrographs were compared using a parameter which contained volume, peak, and shape factors. One-half of the selected storms were used to calibrate the models. For both models, there were no significant differences between the simulated and actual runoff volumes and peak runoff rates. Parameters obtained during the calibration process and relationships developed to estimate antecedent moisture and to modify tabulated runoff curve numbers were used to simulate the runoff hydrograph from the remaining storms. These remaining storms or test storms were simulated only once in order to imitate an ungaged situation. In general, both the Huggins and SCS model performed similarly on the test storms, but the level of model performance was lower than that for the calibration storms. For both models, the two-day antecedent rainfall was more important than the five-day in determining antecedent moisture and modifying tabulated curve numbers. The time of concentration which resulted in good hydrograph simulations was about three times larger than that estimated using published empirical relationships.     

聊城市城市地表径流污染负荷估算

基于ArcGIS软件,依据土地利用、土壤类型等遥感数据生成聊城市东昌府城区的土地利用图,统计不同土地利用类型的面积,将研究区域按不同功能分为居住区、交通区、工业区、绿化用地、公共建设用地和未利用土地,选择不同CN(Curve Number)值,采用SCS径流曲线模型计算2009年的径流深度和年径流量。结果表明:聊城市东昌府区2009年不同功能分区的降水径流深度分别为272.47 mm、465.00 mm、277.16 mm、30.68 mm、128.47 mm、167.51 mm,同时,根据研究区域内悬浮物(SS)、化学需氧量(COD)、总氮(TN)、总磷(TP)等污染物的平均浓度,估算得出它们的负荷量分别为8 558.8 t、2 415.32 t、201.29 t、10.08 t。     

东江流域1959-2009年气候变化及其对径流的影响

依据东江流域21个气象站1959-2009年逐年平均降雨、蒸发、日照、湿度及气温等气象要素序列,选择常用的线性倾向估计及非参数M．K等趋势分析方法,分析了东江流域近50年来气温、降水、蒸发、日照及湿度等气象要素的变化趋势。选择降雨和蒸发两个气候要素两两组合,构成未来气候变动的36种假想情景,运用改进的SCS月模型模拟计算了顺天流域年径流量的变化幅度。结果表明：在过去的50年间,流域降雨量呈不显著增长,而气温则为显著上升,其他气候要素如蒸发、日照及湿度等均呈不同程度减少趋势;关联度分析表明降雨在所有气象要素中与径流的关联度为最大,说明了在东江流域降雨是径流量变化的主要驱动因子;未来流域降雨增加,蒸发减少的气候情景模式下,径流量会有所增加,反之亦然;由降雨变化引起的流域月径流量的增幅较由蒸发变化引起的相应流量的增幅变化大。     

RUNOFF VOLUME ESTIMATION USING GIS TECHNIQUES1

ABSTRACT: Rainfall runoff of six watersheds was modeled via the Soil Conservation Service runoff curve number model in two ways: conventionally (manually) and via a geographic information system (GIS). Input data (elevation, soils, and landcover) were digital for the latter method. In contrast to previous studies, the GIS was ised for all phases of the modeling process, including watershed delineation and routing of runoff. A comparison between the two methods was consistent with results reported by others and indicates that the use of a GIS is an acceptable alternative to the conventional method for watersheds lacking relatively flat terrain. Given this limitation, the GIS method may prove advantageous over manual methods when study areas are large or numerous, runoff is modeled repetitively, alternative landcover scenarios are explored, or a digital database already exists for the study area.     

汶川地震灾区小流域洪水计算方法初探

汶川地震灾区小流域山洪不仅造成巨大损失,同时也是泥石流等灾害的激发因素,探寻一种准确且可操作的洪水峰值流量计算方法对防灾减灾具有重要意义。本文选择不同产流和汇流计算方法,组合成不同水文模型,进行小流域洪水过程计算,对模拟结果和参数选择进行对比,旨在探究最适合该地区的小流域水文计算方法。分别选择SCS曲线法、Green-Ampt入渗法、初损稳渗法进行坡面产流计算,应用SCS单位线法、Snyder单位线法和运动波方程进行坡面和沟道汇流计算,组合成5种小流域产汇流计算模型,利用6场洪水进行参数率定和结果验证。模拟结果对比分析,得出SCS曲线法是最适宜的产流模型,其与SCS单位线、运动波汇流计算方法组合而成的SCS和SKK模型,峰现时间的模拟误差最小,在0~25 min之间;洪峰流量模拟的相对误差较小,平均误差不超过4%;洪水总量模拟误差在10%左右。另外,这两种模型参数设置及确定较简单,更适合在数据稀缺的小流域中进行洪水模拟应用。研究可为汶川地震灾区小流域山洪和泥石流等灾害的流量估算提供方法和参数借鉴。     

深圳市光明新区城区径流污染负荷估算研究

针对深圳市光明新区城区径流,采用SCS径流曲线模型对其SS、COD、TN及TP等污染负荷进行了估算。结果表明,光明新区城区径流污染负荷中,SS、COD、TN、TP的污染负荷量分别为18527.8、11023.81、197.29和91.58 t,其中COD的排放负荷已超出其收纳水体茅洲河环境容量6.0倍,COD和SS的年输出系数值也明显高出同类城市,SS和COD为该地区降雨径流中的主要污染物。     

URBAN STORMWATER QUANTITY/QUALITY MODELING USING THE SCS METHOD AND EMPIRICAL EQUATIONS1

ABSTRACT: Runoff depth and pollutant loading (Biological Oxygen Demand [BOD₅], Total Suspended Solids [TSS], Total Kjeldahl Nitrogen [TKN] and lead [Pb]) computations of urban stormwater runoff from four small sites (i.e., 14.7–58.3 ac) in South Florida were performed using the Soil Conservation Service (SCS) hydrology method and empirical equations developed by the U.S. Environmental Protection Agency (EPA). Each site had different predominant land uses (i.e., low density residential, high density residential, highway and commercial). Quantity and quality data from 95 storm events at these sites were measured by the U.S. Geological Survey (USGS), and used for calibration of the methodology to derive appropriate input parameters. Calibrated input parameters were developed for each land use to test the applicability of the methodology in small sub-tropical urban watersheds, and to provide hydrologists with a way to select appropriate parameter values for planning studies. A total of 16 independent rainfall events were used for verification of the methodology. Comparisons of predicted versus measured data for both hydrographs and pollutant loadings were performed.