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1.
多水塘系统是农业流域常见的小型水利工程,空间交错的沟塘结构导致其水文连通过程复杂多变,对流域营养盐截源控污影响显著。为强化多水塘系统水文连通对磷输移影响的认知,以多水塘系统及其水文连通的定义内涵为切入点,归纳了多水塘水文连通性评估方法;基于景观格局、水文过程和生物地球化学过程聚焦多水塘系统对磷输移的调控作用;阐明了水文连通变化通过驱动干湿交替对磷输移环境以及通过调节水分滞留时间对磷输移通量的影响。指出多水塘系统水文连通变化的驱动机制、沟塘滞留效率的尺度扩展、定量模拟和优化调控是未来多水塘系统环境效应研究的重要方向,以期为保障多水塘水质改善功能提供理论依据。  相似文献   

2.
Landslides are a main cause of human and economic losses worldwide. For this reason, landslide hazard assessment and the capacity to predict this phenomenon have been topics of great interest within the scientific community for the implementation of early warning systems. Although several models have been proposed to forecast shallow landslides triggered by rainfall, few models have incorporated geotechnical factors into a complete hydrological model of a basin that can simulate the storage and movement of rainwater through the soil profile. These basin and full hydrological models have adopted a physically based approach. This paper develops a conceptual and physically based model called open and distributed hydrological simulation and landslides—SHIA_Landslide (Simulación HIdrológica Abierta, or SHIA, in Spanish)—that is supported by geotechnical and hydrological features occurring on a basin-wide scale in tropical and mountainous terrains. SHIA_Landslide is an original and significant contribution that offers a new perspective with which to analyse shallow landslide processes by incorporating a comprehensive distributed hydrological tank model that includes water storage in the soil coupled with a classical analysis of infinite slope stability under saturated conditions. SHIA_Landslide can be distinguished by the following: (i) its capacity to capture surface topography and effects concerning the subsurface flow; (ii) its use of digital terrain model (DTM) to establish the relationships among cells, geomorphological parameters, slope angle, direction, etc.; (iii) its continuous simulation of rainfall data over long periods and event simulations of specific storms; (iv) its consideration of the effects of horizontal and vertical flow; and (vi) its inclusion of a hydrologically complete water process that allows for hydrological calibration. SHIA_Landslide can be combined with real-time rainfall data and implemented in early warning systems.  相似文献   

3.
4.
At the Midway, Utah, USA fish hatchery, a groundwater development program was conducted to help transition the facility from surface to groundwater in response to contamination by whirling disease, which is caused by a trout parasite. The unconfined aquifer system that provided the hatchery water became infected through the recharge of infected irrigation water obtained from the Provo River. Whirling disease was first discovered in Utah in 1991 at a private fish farm. Infected fish from the farm quickly infected many of Utah’s waterways and infected the hatchery in 2000. Because the parasite completes its life cycle in multiple organisms and can survive for decades in a variety of harsh environments, a comprehensive study of the hydrostratigraphy and hydrodynamics at the hatchery was critical in order to understand the hazard and avoid further contamination. Drilling revealed the presence of a shallow unconfined (surface to 10 m) and two deeper confined aquifer systems (~20–35 m and >40 m bgs). Confinement is related to tufa layers, detected both by drilling and reflection seismology. The tufa layers are associated with past discharge of the thermal system. Vertical leakage is apparent from upward hydraulic head gradients and incrementally increasing unconfined aquifer discharge into downstream on-site drainage canals. High-resolution seismic profiles reveal small-offset faults that provide pathways for upward flow. Analysis of water quality data demonstrates an inverted geochemical gradient in that apparent 14C ages, solute concentrations, and temperatures decrease with depth. The origin of the inverted geochemical gradient is related to mixing of upwelling thermal, high-TDS waters with cold, low-TDS systems several kilometers up-gradient from the hatchery. Thermal upwelling appears to be fault controlled. Up-gradient of the hatchery, near-surface groundwater mixes with a larger proportion of thermal groundwater than does deeper groundwater. As these mixed systems flow toward the hatchery, a major locus of groundwater discharge, they are segregated into confined and unconfined compartments. Our study requires integration of hydrological, geochemical, and geophysical strategies in order to understand a complex natural hazard and thus may serve as a model for other similarly complex hydrological environments.  相似文献   

5.
ArcTOP:TOPKAPI与GIS紧密连接的分布式水文模型系统   总被引:4,自引:0,他引:4  
刘志雨 《水文》2005,25(4):18-22
基于遥感(RS)和地理信息系统(GIS)的分布式水文模型已成为当前水文科学发展的前沿,地理信息建模系统是目前地理信息系统研究的热点问题之一。目前实现通用GIS空间分析功能与水文模型的集成主要有四种途径:水文模型嵌入CIS平台.GIS功能嵌入水文模型.水文模型和GIS的松散连接以及水文模型和CIS的紧密连接。本文提出的ArcTOP分布式水文模型系统,运用ArcViewGIS提供的宏语言,将以物理概念为基础的分布式水文模型TOPKAPI和CIS紧密连接,实现分布式水文模型和GIS的完全集成。  相似文献   

6.
The catastrophic flood of February 1986 in the polje of Cetinje, unrecorded in the 500-year long written history of the old Montenegrin capital, was an opportunity to examine some specific features of the complex hydrogeologic system. Above all, it is the incompatibility of the epikarst and endokarst systems of karst aquifers, collectors-conductors, and groundwater reservoirs that causes a hydrological environmental impact on the polje in extremely wet (autumnwinter) periods of the year. This year's flood has indicated that this epikarst system, generally dry most of the year, has a relatively large water-receiving capacity, and that the deeper endokarst system has all attributes of a karst aquifer, much variable transmissivity and low storage capacity.  相似文献   

7.
我国水文情报预报工作的主要成就及展望   总被引:2,自引:2,他引:0  
梁家志  乐嘉祥 《水文》1999,(5):20-23,26
新中国成立50年来,水文情报预报工作取得了成就,在水情信息采集和传输方面,全国已有水文报汛站8000余处,在25处重点防洪河段和150座大型水库上建立了水文自动测报系统,共计有遥测站近2000个,已有22个省(市,区)和7个流域管理机构的水情部门通过计算机广域网互传水情信息。在水文预报技术方面,开发研制了适合中国特色的许多水文模型。随着计算机的广泛应用,水利信息中心初步建立了水雨情信息服务系统,包  相似文献   

8.
Estimation of geohydrologic properties of fractured aquifers in hard crystalline and/or metamorphosed country rocks is a challenge due to the complex nature of secondary porosity that is caused by differential fracturing. Hydrologic potentiality of such aquifers may be assessed if the geological controls governing the spatial distribution of these fracture systems are computed using a software-based model. As an exemplar, the Precambrian metamorphics exposed in and around the Balarampur town of Purulia district, West Bengal (India) were studied to find out the spatial pattern and consistency of such fracture systems. Surfer and Statistica softwares were used to characterize these rock masses in terms of hydrological, structural and lithological domains. The technique is based on the use of hydraulically significant fracture properties to generate representative modal and coefficient of variance () of fracture datasets of each domain. The is interpreted to obtain the spatial variability of hydraulically significant fracture properties that, in turn, define and identify the corresponding hydrolithostructural domains. The groundwater flow estimated from such a technique is verified with the routine hydrological studies to validate the procedure. It is suggested that the hydrolithostructural domain approach is a useful alternative for evaluation of fracture properties and aquifer potentiality, and development of a regional groundwater model thereof.  相似文献   

9.
黄淮海湿地系统分类体系构建   总被引:2,自引:0,他引:2  
黄淮海平原是3条大河在时空演化过程中形成的,其内形成了复杂多样的湿地系统和类型.由于受强烈的人类活动影响,湿地系统演变的自然规律特性逐渐消失,明显受到人为调控下的水文情势制约,并在空间分布上也是持续萎缩,湿地系统的整体性联系被明显打破,景观破碎化、退化严重.构建一个符合现存湿地情形、宜于湿地管理的分类体系,对于保护和管理好湿地,发挥其功能具有重要意义.在湿地系统分类中,就人工湿地的划分,突出了其服务功能性质,有利于人工湿地的归类管理.  相似文献   

10.
可持续水资源系统管理研究与展望   总被引:39,自引:1,他引:39       下载免费PDF全文
夏军 《水科学进展》1997,8(4):370-376
依据近些年国际水文水资源学术会议及交流等信息,综述近年来社会可持续发展对水资源系统管理提出的新的挑战及国际上可持续水资源系统管理研究的若干特点等问题,提出了几点认识和建议。  相似文献   

11.
Over a period of three hydrological years during which precipitation was highly variable, measurements of discharge, electrical conductivity, temperature and chemical components of the water at the Cañamero spring (southern Spain) were taken in order to characterise the hydrogeological functioning of the karst aquifer that it drains. The results obtained from analysis of the frequency distribution of electrical conductivity data revealed histograms with a plurimodal morphology (up to 5 modes) and a range of variation that increased with greater pluviometry during the study period. The discharge from this spring increased sharply a few days after major rainfall episodes and, when the discharge reached a value of approximately 3.73 m3/s, an overflow spring started to function. During high-water periods, there were sudden and large falls in EC, temperature and all the chemical components dissolved in the water. This high variability reflects the predominance of groundwater flow through karst drains, a typical feature of conduit flow systems. The considerable hydrochemical heterogeneity observed is caused by the mobilisation of important volumes of recharge waters from shallow areas of the aquifer (soil, epikarst) towards the discharge point, with greater participation of the unsaturated zone during high-water conditions, and a more active role played by the saturated zone during low-water conditions. In karst systems such as the one drained by the Cañamero spring, it is important to monitor several responses (hydrodynamic, hydrothermal, hydrochemical, etc.), with an appropriate sampling frequency and under different hydrometeorological conditions, in order to achieve an adequate hydrological characterisation. This is fundamental for planning, management and protection of groundwater in karst aquifers.  相似文献   

12.
变化环境下渭河流域水文干旱演变特征剖析   总被引:4,自引:0,他引:4       下载免费PDF全文
环境变化影响区域水资源的可持续开发利用,导致水文过程出现非平稳特征,需发展非平稳水文干旱评估方法。选取渭河流域为研究区,依据流域内2个水文站、62个雨量站和24个气象站1961-2013年数据,基于可变下渗容量模型定量分离气候变化和人类活动对径流衰减的贡献;采用标准化径流指数(Standardized Runoff Index, SRI)剖析水文干旱时空演变特征;提出多种SRI参数化方案,对比评定各方案表征非平稳干旱的合理性以及环境变化对干旱演变的影响作用。结果表明:自1991年以来渭河流域年径流量呈显著衰减趋势,人类活动是径流演变的主要因素,对咸阳和华县站径流量变化的贡献率分别为-66.7%和-71.0%;时变参数方案计算的干旱指数能合理重建历史水文干旱序列;人类活动是渭河流域1991年以来短历时水文干旱发生的主导因素,气候变化主要影响长历时旱涝的演变趋势。  相似文献   

13.
Geophysical, geotechnical and hydrological surveys were conducted in the French Alps on a small landslide in black marl material to assess the stability. The geophysical survey, consisting of electromagnetic, geo-electric and relative differences in water content.

The data on the basal slip surface, together with geotechnical parameters (cohesion and angle of internal friction), were used to make a stability analysis. This analysis revealed that a groundwater level of 4 m below the ground surface is the critical threshold for reactivating the landslide.

The hydrological investigation, which entailed measurements of saturated permeability and pressure heads, indicated that instability depended on long-term wet conditions with little evapotranspiration.  相似文献   


14.
Monitoring and time-series analysis of the hydrological parameters electrical conductivity (EC), water pressure, precipitation and tide were carried out, to understand the characteristics of the parameter variations and their correlations at a coastal area in Busan, South Korea. The monitoring data were collected at a sharp interface between freshwater and saline water at the depth of 25 m below ground. Two well-logging profiles showed that seawater intrusion has largely expanded (progressed inland), and has greatly affected the groundwater quality in a coastal aquifer of tuffaceous sedimentary rock over a 9-year period. According to the time series analyses, the periodograms of the hydrological parameters present very similar trends to the power spectral densities (PSD) of the hydrological parameters. Autocorrelation functions (ACF) and partial autocorrelation functions (PACF) of the hydrological parameters were produced to evaluate their self-correlations. The ACFs of all hydrologic parameters showed very good correlation over the entire time lag, but the PACF revealed that the correlations were good only at time lag 1. Crosscorrelation functions (CCF) were used to evaluate the correlations between the hydrological parameters and the characteristics of seawater intrusion in the coastal aquifer system. The CCFs showed that EC had a close relationship with water pressure and precipitation rather than tide. The CCFs of water pressure with tide and precipitation were in inverse proportion, and the CCF of water pressure with precipitation was larger than that with tide.  相似文献   

15.
Delineation of Lake Karoun watershed in Egypt was carried out and various watershed parameters and environmental characteristics were extracted using geographic information system and remote sensing. Environmental characteristics including normalized vegetation index (NDVI), moisture index, land surface temperature, and land use classes were obtained from high spatial resolution images (Landsat TM). Moreover, hydrological parameters, drainage flow directions, drainage networks, and catchments from digital elevation model have been delineated using the Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) satellite images. As a result, the lake's watershed characteristics including the environmental and hydrological factors for each watershed zone were presented and analyzed. The information generated would be of immense help in hydrological modeling of watershed for prediction of runoff and sediment yield, thereby providing necessary inputs for developing suitable developmental management plans with sound scientific basis.  相似文献   

16.
中国水文预报技术发展的回顾与思考   总被引:4,自引:1,他引:3       下载免费PDF全文
张建云 《水科学进展》2010,21(4):435-443
回顾了中国水文预报技术的发展历程,阐述了中国水文预报技术从经验相关法、流域水文模型,到预报系统发展的整个过程。较详细地介绍了中国常用的水文预报方法、模型和预报系统,及其各自特点和应用条件等,客观评价了中国水文预报技术的水平,深入分析了高强度人类活动引起的下垫面变化和以全球变暖为主要特征的气候变化对流域产流和汇流机制的影响,分析了变化环境下水文预报面临的问题和挑战。展望了中国水文预报技术的发展方向,指出了中国未来水文预报技术的研究重点。  相似文献   

17.
The Parana River is one of the most important fluvial systems of South America and its floodplain includes the most diverse subtropical ecosystem on the continent. However, the relationship between basic aspects, such as the vegetation and geomorphology of the river floodplain, has scarcely been investigated. In this paper, the annual dynamics of vegetation in relation to the geomorphologic and hydrological characteristics of a river floodplain around 31° 30′ S, are analyzed. The annual dynamics of vegetation was investigated using values of the Normalized Difference Vegetation Index (NDVI) obtained from satellite images at two scales of spatial analysis: the first, at the geomorphologic unit level, through several transects crossing the total width of each unit and, the second, through some transects selected from each unit. Our analysis considered variables of different temporal stability (such as geomorphology, hydrology, vegetation, precipitation, and ground temperature), using scenes corresponding to two hydrological cycles of the system (2009 and 2010), which represented relatively “dry” and “humid” years. Five main geomorphologic units were identified in the floodplain of this anabranching system, which were named considering the predominant landforms and the most important (or typical) water course of each area: Bars and Islands of the Main Channel of the Parana River (BI-MCH), Scroll Bars of the Colastine Branch (SB-C), Scroll Bars of the San Javier River Channel (SB-SJ), Crevasse Splays and Levees of the Malo–Mendieta minor channels (CSL-MM), and Crevasse Splays and Levees of the Santa Fe–Coronda river channels (CSL-SFC). These major units are assembled at different general levels and with variable slopes, which partially control the permanence and other characteristics of the flood flow. The crevasse splays and river levees units were predominantly characterized by herbaceous–bushy marshy vegetation, with low mean NDVI values, while SB-C and BI-MCH units showed two types of forests. The latter showed the highest NDVI values. Unit SB-SJ showed mixed characteristics between the two above-mentioned groups. Mean NDVI values were different among the varying geomorphologic units and during the studied years, showing extreme values of 0.25 and 0.80 after both hydrological cycles. According to our results, the main variations in the seasonal dynamics of vegetation show a higher dependence on the dynamics of the hydrological cycle than on surface temperature or precipitation. The hydrological dynamics of the Parana River floodplain are in turn regulated by its geomorphological architecture, so the annual dynamics of vegetation activity in this system are finally influenced by the geomorphologic unit's level, rather than by the short duration modeling processes (i.e., hydrological cycles or drought–flood pulses).  相似文献   

18.
祁连山黑河干流山区水文模拟研究进展   总被引:2,自引:1,他引:1  
流域水文模拟是在认识水文规律的基础上, 对流域水文过程的一种数学描述.黑河流域作为典型的内陆河流域历来是研究寒区、 旱区水文过程的热点区域.祁连山黑河干流山区的水文模拟研究也备受学者们的关注, 经验模型、 概念模型和分布式水文模型在该区域均有应用, 虽然都对出山径流做出了准确的模拟, 但是引进的模型对高寒山区水文过程的刻画不够详细.内陆河高寒山区流域的水文模拟要充分考虑冰川、 积雪、 冻土等因素所引起的特殊寒区水文过程, 准确刻画这些水文过程是高寒山区流域水文模拟成功的关键.今后应该继续加强野外观测, 深入开展冻土水文过程、 冰雪水文过程的模拟研究, 发展真正适合于高寒山区流域水文过程的分布式水文模型.  相似文献   

19.
Gu  ChaoJun  Zhu  Yongqing  Li  Renhua  Yao  He  Mu  Xingmin 《Natural Hazards》2021,109(1):545-566

The runoff and sediment load of the Loess Plateau have changed significantly due to the implementation of soil and water conservation measures since the 1970s. However, the effects of soil and water conservation measures on hydrological extremes have rarely been considered. In this study, we investigated the variations in hydrological extremes and flood processes during different periods in the Yanhe River Basin (a tributary of the Loess Plateau) based on the daily mean runoff and 117 flood event data from 1956 to 2013. The study periods were divided into reference period (1956–1969), engineering measures period (1970–1995), and biological control measures period (1996–2013) according to the change points of the annual streamflow and the actual human activity in the basin. The results of the hydrological high extremes (HF1max, HF3max, HF7max) exhibit a decreasing trend (P?<?0.01), whereas the hydrological low extremes (HBF1min, HBF3min, HBF7min) show an increasing trend during 1956–2013. Compared with the hydrological extremes during the reference period, the hydrological high extremes increased during the engineering measures period at low (<?15%) and high frequency (>?80%), whereas decreased during the biological control measures period at almost all frequencies. The hydrological low extremes generally increased during both the engineering measures and biological control measures periods, particularly during the latter period. At the flood event scale, most flood event indices in connection with the runoff and sediment during the engineering measures period were significantly higher than those during the biological control measures period. The above results indicate that the ability to withstand hydrological extremes for the biological control measures was greater than that for the engineering measures in the studied basin. This work reveals the effects of different soil and water conservation measures on hydrological extremes in a typical basin of the Loess Plateau and hence can provide a useful reference for regional soil erosion control and disaster prevention policy-making.

  相似文献   

20.
全球气候变化影响了气象水文要素的时空分布特性,气象水文干旱事件的转化关系及风险传播特征亟待研究。基于站点、栅格观测资料和CMIP5(Coupled Model Inter-comparison Project Phase5)的19个气候模式输出数据,采用新安江等4个水文模型模拟了中国135个流域历史(1961—2005年)和未来时期(2011—2055年,2056—2100年)的水文过程,计算了SPI(Standard Precipitation Index)和SRI(Standard Runoff Index)干旱指标,通过游程理论识别了气象干旱与水文干旱事件,利用Copula函数与最大可能权函数度量二维干旱风险特征,定量评估了气象干旱至水文干旱的潜在风险传播特性。结果表明:①气象-水文干旱对气候变化响应强烈,华北和东北地区的干旱联合重现期增大,干旱潜在风险减小,华中和华南地区的干旱联合重现期减少60%~80%,干旱潜在风险增加;②气象干旱与水文干旱风险在历史和未来时段均存在显著的正相关关系,相关系数超过0.99;③各流域水文干旱风险变化对气象干旱风险变化的敏感程度不会随气候变暖发生较大变化,但未来北方地区水文干旱同气象干旱同时发生的概率将会小幅度增加。  相似文献   

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