共查询到18条相似文献，搜索用时 140 毫秒
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变化环境下洪涝灾害呈加剧趋势，探讨暴雨洪水响应机理成为了地理、水文等学科关注的重难点问题之一。本研究基于野外综合对比观测试验，探讨了不同土地利用/覆被下的土壤水响应特征及产汇流机制。结果表明：长三角地区长时间序列土壤含水率季节性变化较小，其变化幅度总体表现为表层和汛期较大，而深层和非汛期较小。杨梅林纵剖面土壤含水率从上到下呈现逐渐增加的趋势，而耕地和竹林趋势相反。从表层到深层，山坡地、城镇用地和荒地土壤含水率呈现反S型、W型和V型波动变化特征。试验流域洪水特征与总降雨量相关性较强，蓄满产流是该地区主要产流方式。城市化区域不透水面扩张，导致降雨下渗减少，径流系数增加，从而使得洪峰水位上升。 相似文献
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根据喀斯特流域多孔介质与裂隙水流特征,建立了达西流、裂隙渗流与槽蓄汇流演算相结合的混合汇流演算模式,实现了对分布式水文-植被-土壤模型(DHSVM)的改进。利用贵州普定喀斯特生态水文试验站陈旗小流域观测资料,对模型计算的流量过程及植被截流、蒸散发及土壤含水率时空分布进行验证。结果表明,模型能较好地模拟喀斯特流域陡涨、陡落的流量过程。同时,模型能模拟出土壤含水率、实际蒸散发与降雨、下垫面岩溶裂隙、植被覆盖的响应关系,对分析中国南方喀斯特地区下垫面变化条件下的生态水文效应具有重要意义。 相似文献
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快速城市化显著改变了城市下垫面空间特征,对地表产汇流过程产生了重要影响。综述城市下垫面空间特征对地表产汇流过程的影响研究进展,以下垫面空间特征对产汇流过程的影响为主线,聚焦不透水面和微地形两类空间特征,总结城市下垫面空间特征及其表征方法;从不透水率与不透水面空间变化、数值模拟与物理实验等方面,分别梳理不透水面和微地形等空间特征对地表产汇流过程的影响研究成果。展望未来城市下垫面空间特征对地表产汇流过程的影响研究重点和发展方向,主要包括影响机理解析、主控空间特征参数识别与敏感性分析、城市水文效应适应性应对等,以期为快速城市化下城市水文效应解析和城市洪涝灾害防治提供一定参考。 相似文献
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近年来的水利水电建设和土地开发利用等,已经明显地改变了我国许多流域的产汇流条件.因此迫切需要发展从暴雨资料来推求设计洪水的途径。现行的计算程序是先拟定一次符合设计标准的设计暴雨过程,再推求该暴雨所形成的洪水过程。它实质上是假定流域产汇流系统的输入项(暴雨过程 H(t))和输出项 相似文献
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我国南方岩溶流域和非岩溶流域下垫面条件和含水介质结构的差异造成了不同的产汇流过程及机制,进而导致不同释水时段径流组分的开发利用价值不同。为深入理解岩溶流域的产汇流机制并探索岩溶流域的水资源评价方法,文章对鄂西庙沟岩溶流域和高家坪非岩溶流域共31次洪水过程进行了流量衰减分析,对比分析了两个流域的标准衰减方程、典型次降雨的释水过程以及不同洪峰流量下的径流组分差异。结果表明:岩溶流域的释水过程快于非岩溶流域,其衰减系数比非岩溶流域大40％;两个流域的河流基流均来自裂隙介质释水,裂隙介质为流域的主要储水空间,但非岩溶流域的裂隙介质比例比岩溶流域高8.8％;随洪峰流量增加,两个流域的地表径流占比均呈对数形式增大,地下径流占比均呈对数形式减小;岩溶流域径流组分随洪峰流量变化比非岩溶流域更为敏感,其地表径流占比变幅为4％~40％,而非岩溶流域则始终小于10％。文章定量评价了管道和裂隙介质在流域中的导水及储水功能,在进一步刻画岩溶流域产汇流过程及机制方面进行了有益的探索,研究结果可为岩溶山区水资源评价和流域水文模型的改进提供科学依据。 相似文献
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柳林水文站是邢台市的1982年设立的小面积径流实验站,设站主要目的是收集流域内的暴雨洪水资料,探求产汇流关系参数在流域内随下垫面条件变化的规律。为了适时调整水文站网,对设站年限进行分析是十分必要的。分别采用产汇流参数检验法、抽样误差检验法、设计洪水和设计枯水检验法对柳林站的设站年限进行了分析。并在此基础上得出了综合结论。 相似文献
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目前,中国城区大多缺乏实测管道流量数据,给城市水文模型构建及精细化模拟带来了挑战。在北京亦庄经济开发核心区下垫面精细数字化的基础上,以典型点的最大径流深为验证要素,以实地踏勘为主、经验率定为辅,分别选取2012年"7·21"和2011年"6·23"两场典型大暴雨径流过程,完成了区域SWMM(Storm Water Management Model)模型的参数率定和验证;并就不同重现期设计暴雨下,不同典型用地子汇水区的产汇流响应特征及内涝交通拥堵风险进行了分析及评估。结果表明:随着重现期的增加,道路与交通设施用地对暴雨增幅的响应速率远高于公园绿地的响应速率,前者的内涝交通拥堵风险亦远高于后者;间接反映了不同下垫面条件造成产汇流响应的差异程度。相关成果可为区域城市洪涝管理与预警提供决策参考。 相似文献
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为探讨中国东部地区变化环境下水循环演变机制,通过水文站网加密观测、构建不同特征试验流域等方法,揭示了不同土地利用和不同城镇化水平下水文要素分布及响应规律。结果表明:①小流域内场次极端降雨局部差异较大,主要受到微地形和风向的影响。②鄞江镇试验流域水位涨幅和单位雨量水位涨幅均高于天然画龙溪试验流域,主要受到了流域大小和城镇化率等因素的影响。③城镇用地和耕地土壤水消退过程较快,林地退水过程相对较慢;浅层10cm、20cm和40cm土壤含水率对降雨滞后响应时间分别为0~0.25h、0.25~0.75h和0.5~0.75h,而深层(60cm和80cm)土壤含水率由于受到优势流的影响,响应较为复杂,响应时间变动范围较大。④小流域地下水对降雨的响应存在滞后性,响应时间为6.5~12h。 相似文献
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Watershed urbanization and changing flood behavior across the Los Angeles metropolitan region 总被引：3，自引：0，他引：3
This article examines the effects of watershed urbanization on stream flood behavior in the Los Angeles metropolitan region.
Stream gauge data, spatially distributed rainfall data, land use/land cover, and census population data were used to quantify
change in flood behavior and urbanization in multiple watersheds. Increase in flood discharge started at the very early stage
of the urbanization when the population density was relatively low but the rate of increase of flood discharge varied across
watersheds depending on the distribution of the imperviousness surface and flood mitigation practices. This spatial variability
in rainfall–runoff indices and the increasing flood risk across the metropolitan region has posed a challenge to the conventional
flood emergency management, which usually responds to flood damages rather than being concerned with the broader issues of
land use, land cover, and planning. This study pointed out that alternative land use planning and flood management practices
could be mitigating the urban flood implemented hazard. 相似文献
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Muhammad A. Al-Zahrani 《Arabian Journal of Geosciences》2018,11(9):208
In the past few decades, rapid urbanization has occurred in many regions of the Kingdom of Saudi Arabia due to increasing population and urban development. Additionally, the effects of global warming on rainfall characteristics have been observed. This rapid change in urbanization and climate change has cause significant changes in the nature of land surfaces and rainfall patterns, which affect the runoff process and the amount of surface runoff during floods. This study investigated the effect of urbanization and rainfall intensity for Hafr Al-Batin watershed located in Saudi Arabia. For this purpose, a hydrologic model, HEC-HMS, was adopted to simulate the flow of different rainfall intesities and urbanization levels. Simulated results showed that for a 100-year storm, a 24-h duration, and an urbanization level of 80%, the peak flow was 213% higher than the estimated current peak and the runoff volume was 112% higher than the current runoff volume. These results show a strong linear correlation between the level of urbanization and both peak discharge and runoff volume. Furthermore, the results indicate that for short return periods, the peak flow is more sensitive to the level of urbanization compared to long periods. 相似文献
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Yuyu Zhou Yeqiao Wang Arthur J. Gold Peter V. August Thomas B. Boving 《GeoJournal》2014,79(2):155-166
In this study, we investigated the relationship between watershed characteristics and hydrology using high spatial resolution impervious surface area (ISA), hydrologic simulations and spatial regression. We selected 20 watersheds at HUC 12 level with different degrees of urbanization and performed hydrologic simulation using a distributed object-oriented rainfall and runoff simulation model. We extracted the discharge per area and ratio of runoff to base flow from simulation results and used them as indicators of hydrology pattern. We derived percentage of ISA, distance from ISA to streams, and stream density as the watershed characteristics to evaluate the relationship with hydrology pattern in watersheds using ordinary least square, spatial error and spatial lag regression models. The comparison indicates that spatial lag regression model can achieve better performance for the evaluation of relationship between ratio of runoff to base flow and watershed characteristics, and that three models provide similar performance for the evaluation of relationship between discharge per area and watershed characteristics. The results from regression analyses demonstrate that ISA plays an important role in watershed hydrology. Ignorance of spatial dependence in analyses will likely cause inaccurate evaluation for relationship between ISA and watershed hydrology. The hydrologic model, regression methods and relationships between watershed characteristics and hydrology pattern provide important tools and information for decision makers to evaluate the effect of different scenarios in land management. 相似文献
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天山南坡黄水沟与清水河寒区流域极端水文事件对气候变化的响应 总被引：1，自引：0，他引：1
冰川、积雪和冻土变化产生的水文效应对下游水资源供给具有重要影响,近几十年来新疆区域洪水呈显著加重趋势,尤其是南疆区域洪水明显加剧. 以天山南坡黄水沟与清水河寒区流域为研究区域,通过分析水文站极端水文事件,结合流域上游山区巴伦台气象站资料,研究了高寒山地流域在气候变化背景下极端水文过程出现时间、年最大和最小径流的响应特征. 结果表明：1986年是水文过程的突变点,从1986年开始随着降水、气温的增加,河流径流量呈增加趋势;最大年径流出现时间从6月中下旬推迟到7月下旬;最大径流和最小径流与年径流量呈正相关关系,最大径流与夏季降水关系密切,而最小年径流与冬春季的气温关系密切. 随着1986年以来的气温升高,冻土退化产生的水文效应使冬季径流增加明显,也使年最小径流明显增大;1986年以来降水变化决定着年径流量增加,使年最大径流集中出现在夏季且量级增大. 总体来讲,20世纪80年代中期以后山区河流年极端洪峰量增大,洪水量增多,年际间变化幅度明显增大,从而对下游造成更严重的灾害. 因此,加强气候变化对寒区流域水资源和洪水灾害的影响评估,使科学技术在减灾方面发挥主导作用. 相似文献
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为实现中小流域降雨径流过程精细化模拟, 合理估算水文模型参数的空间分布具有重要意义。基于新版全球数字土壤制图系统(SoilGrids)构建栅格新安江模型(GXM)参数化方案, 对陕西省陈河流域2003—2012年16场洪水进行模拟, 与新安江模型计算结果进行对比, 开展基于洪水过程划分的自由水蓄水容量敏感性及空间分布特征量化分析。结果表明: GXM模拟的峰现时间误差水平降低约0.31 h, 洪峰和洪量模拟精度较高, 模型能够对土壤水饱和度等水文要素的动态空间分布进行较合理的模拟; 自由水蓄水容量参数对洪峰和涨洪过程的确定性系数以及涨洪段的洪量相对误差影响较大, 对退水过程影响小; 自由水蓄水容量在陈河流域河谷和山脊附近较大, 坡段中部较小。 相似文献
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Effects of land use change on flood characteristics in mountainous area of Daqinghe watershed, China 总被引：2，自引：0，他引：2
Land use has changed in the Daqinghe watershed during 1956–2005, and it has influenced the flood peak and volume. In order to reveal the effects of land use change on flood characteristics in Daqinghe watershed, we selected 2 sub-watersheds and used remote-sensed land use data of 1980 and 1996 to analyze changes in land use and also selected several combinations of similar rainfall events and the corresponding flood events to show how changes in land use affect floods. The forest and urban area increased and other types decreased, and flood peaks and volumes tended to decrease under similar rainfall events. To quantify the extent of change in land use affecting floods, a hydrological model incorporating the land use was established. The model combines infiltration excess and saturation excess runoff generation mechanism in each type of land use, and the simulation results agreed well with the measured flood processes in the two selected watersheds. Several floods of different return intervals were selected to be modeled under the 1980 and 1996 land use conditions. The results show that both flood peak and volume decreased under the 1996 land use condition in comparison with the 1980 land use condition in the two watersheds. Most of the flood peaks decreased <5 %, but the volume decreased to a greater extent. This result can be helpful in modifying design flood. 相似文献
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用BATS模型模拟径流的个例研究 总被引：3，自引：0，他引：3
为了解陆气间水热交换在径表成中的作用,本文采用ＢＡＴＳ模型模拟了淮河流域山区和平原在１９９１年汛期５０天的暴雨洪水过程,计算了径流,土壤温度和感热,通量,并用常规的汇流计算方法得到了流域出口断量过程线。 相似文献