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1.
分布式流域水文模型从DEM数据中提取河流,由于地图数据的比例尺、DEM网格的分辨率等原因,生成的河流可能与真实的河流不重合,流域内的径流可能汇集不到出口断面,必须对DEM数据进行处理。目前GIS软件中常用的处理方式是将河流经过的网格高程普遍降低,这种方法还不够理想。理想的DEM数据处理方法应满足以下原则:修改后生成的河流与真实的河流重合,流域内的径流能够汇入河道到达流域出口断面;DEM数据中网格的高程来自实测地图,最能代表网格的高程,只是由于对网格高程的插值滤掉了一些地形细节,因此高程修改的网格数目应达到最小。基于这个原则,提出DEM数据修改方法,平滑掉河流经过的凸起网格并且填充流域内的洼地,修改最少的网格高程,使由DEM数据生成的河流能够与真实的河流重合,达到模拟真实的径流流动路径的目的。 相似文献
2.
以丰乐河流域为研究对象,选用SWAT2000模型定量化研究不同子流域划分层次对模型模拟结果的影响,得到结论:①不同的子流域划分层次在阈值范围内对径流过程的影响较小,而对泥沙、营养物的影响较大;②就本流域而言,子流域划分层次对模拟结果的影响存在上限、下限两个阈值,高于上限,出现模拟失真,低于下限,尽管可通过调参获得满意结果,但难以满足流域规划与管理对空间数据的要求,阈值的确定与具体的流域特征有关;③就本流域而言,当子流域划分数量比较少时,出口泥沙响应的敏感性高于总磷、总氮;当子流域划分数量比较多时,出口泥沙响应的敏感性要低于总磷、总氮。 相似文献
3.
基于GIS平台及其水文模块,利用流域划分的原理,对DEM进行预处理,提取了福建区域内的子流域分布,结合省内重要人口聚集地、交通干线、水系干流、海岸线等地理要素空间分析,对省内一重山范围进行提取研究,基于GIS三维视角及野外验证,提取的一重山范围效果较好,表明该技术方法可行,在一定程度上可以解决目前要实施的国土空间规划、... 相似文献
4.
基于分布式大流域径流模型的中国西北黑河流域水文模拟 总被引：1，自引：0，他引：1
水资源短缺是中国西北干旱地区长期的问题,区域人口增加、城市化扩张,加之气候变化的影响进一步加剧了西北地区水资源短缺,也使生活用水、灌溉用水、工业用水和维持生态系统稳定的用水危险加剧.采用分布式大流域径流模型(DLBRM)模拟黑河流域水文(中国第二大内陆河,流域面积128 000 km2)来理解区域的冰川和积雪融化水、地下水、地表水、蒸散发等方面的分布,评估气候变化对水文的影响和冰川退缩对中游和下游来水量的影响.模拟结果表明,黑河流域的大部分产流那源于黑河上游地区的祁连山.模拟1990-2000年黑河河流日流量变化结果认为,黑河中游正义峡给下游的供水为10×108m3,其中地表径流占51%,层间流占49%.中游地区沙土具有较高的蒸腾发能力,近一半的地表水被蒸发掉.模拟实践证明,分布式大流域径流模型可以结合气候变化、水资源管理方面的成果,改进流域水文模拟的精度. 相似文献
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6.
地形特征(如高程和坡度)和水文特征(如河流长度和河流坡度)是分布式流域水文水质模型的基础输入参数,用于量化描述模型模拟流域的自然特征。这些特征参数的准确性直接影响水文水质过程模拟的准确性。应用数字高程模型(Digital Elevation Model,DEM)在4个不同地形的子流域研究了10种不同分辨率DEM对平均高程、流域面积、坡度、河流坡度、最长河长等参数的影响。结果表明,随着DEM分辨率降低,流域地形变缓,流域平均坡度逐渐减小;随着DEM网格分辨率的变化,子流域划分范围和河道位置也都可能发生变化,且该变化在地形起伏较小的丘陵平原地区较明显,子流域集水面积和河长进一步随之改变;河流坡度随DEM分辨率降低则呈无规则变化。从地形和水文参数两方面揭示了DEM 分辨率在分布式流域模型中的不确定性影响。 相似文献
7.
大尺度流域水文模型一般只模拟河道径流,对河流水深和流速并不关注。在进行河流-地下水相互作用模拟时,河流水深（水位）是一个重要因素,其时空变化及其对河流-地下水水量交换的影响应加以考虑。本文就流域分布式水文模型中河流水深的时空变化计算及其与地下水的实时耦合模拟进行了研究,提出了相应的计算方法,改进了大尺度水文模型WATLAC,并通过V-型流域考题进行了检验。模拟结果显示,模型有效地模拟了V-型流域的河流水深、地下水水位沿河道的时空变化以及河流与地下水的水交换量,揭示了河流-地下水相互作用关系在降雨过程中的变化规律及主控因子。此外就河床糙率对河流水深及河流与地下水间水交换量的影响做了模拟分析,发现河床糙率的改变将影响河流水深,从而进一步影响河流与地下水的水交换量。本文提出的算法较为真实地模拟了河流洪水演进过程及其对河流-地下水相互作用的影响,模型适用于河流-地下水相互作用明显的区域,可作为评估地表-地下水相互影响的有效计算工具。 相似文献
8.
借助于GIS技术对大流域进行划分与编码.修正实测河道上部分栅格单元的高程,以避免大面积“伪洼地”的出现,从修正后的栅格型数字高程模型(DEM)提取出与实测河网比较一致的模拟河网.提取出模拟河网后,再进行河网的编码,以及流域的划分与编码.提出了一种对Pfafstetter规则的改进方法,并且按照改进后的Pfafstetter规则来对河网与流域进行编码.所有编码工作是由本次研究中专门编制的程序来自动完成.将提出的方法应用于黄河流域,将整个黄河流域划分为8 255个子流域并赋予了Pfafstetter编码. 相似文献
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黄土高原西部土壤水分时空变化模拟研究——以安家坡流域为例 总被引：3，自引：2，他引：1
土壤水作为陆地水循环和水量平衡的一个重要组成部分,在土壤-植被-大气连续体物质与能量转化中起着重要的作用,成为陆面过程研究中的重要参量.选择黄土高原西部的安家坡流域,采用多点长序列观测方法,对该区域土壤水分的时空变化规律进行研究.结果表明:坡向和土地利用类型是小流域土壤水分变异的重要影响因素,得出了不同立地条件下土壤水分的剖面变化与时间的动态规律.在此基础上,利用土壤湿度指数结合主要影响因素预测土壤水分的时空变化,旨在为黄土高原大中尺度的土壤水分模拟提供思路. 相似文献
11.
Stuart J. Jones 《地学学报》2004,16(3):121-127
An understanding of how drainage patterns respond to tectonics can provide an insight into past deformational events within mountain belts and where sediment flux is supplied to depositional basins. The transverse rivers draining the Spanish Pyrenees show sudden diversions to axial courses and the capture of lateral systems producing large trunk rivers that break through the thrust front at structurally controlled points. The drainage reorganization from the initial regularly spaced pattern in the Late Eocene caused by the growth of thrust‐controlled topography influenced the location of outlets into the Ebro basin. The headward capture and merger of rivers as a result of structural diversion formed two large terminal fan systems during the Oligo‐Miocene along the Pyrenean thrust front. The early structural topographic controls on drainage evolution will have long‐term effects on sedimentation and stratigraphic architecture of foreland basins. This will only be maintained as long as there is tectonic uplift and the river systems strive to re‐attain a regular drainage spacing across the orogenic belt as partly achieved in the Pyrenees. 相似文献
12.
三峡如何贯通并实现东流的问题历来是学术界关注和争议的问题。笔者认为，三峡的连通不是简单的江汉平原水系与四川盆地水系的连通，而是包括三峡库区段众多中小盆地及其水系的纵横交织性连通，连通过程中有地表水的溯源侵蚀作用，也有地下水的溶蚀、风化和侵蚀作用。地表水的流路与地下水的流路不尽相同，地下水的作用形成地下河，许多峡谷是地下河经进一步溶蚀垮塌形成的。地表河与地下河相连接构成长江主河道。虽然当时的水流有东西分流，但没有明显的分水岭，许多地段水流的方向因各盆地降雨量的变化而频繁改变。由于河流下切和新构造运动造成地表西升东降，最后流向四川盆地的水改向东流，形成统一的长江。三峡库区段是年轻的河段，成为完全地表河和东流的时间不长。这些认识对深化大江大河的成因理论具有重要的意义。 相似文献
13.
岩溶水系统的划分研究是水均衡分析、水资源评价的基础。南洞地下河是中国南方4个超大型地下河系统之一,其水文地质条件复杂,开发潜力巨大。由于南洞地下河系统蒙自盆地内有第三系阻水深槽存在,使得该区地下水位高于南北两侧,部分研究认为该阻水带是南洞地下河系统的南边界。本次通过进一步收集盆地内部和外围水文地质钻孔及地热钻孔资料、野外调查、洞穴探测及示踪试验,认为盆地内阻水深槽并不阻挡深部地下水,南洞地下河系统南边界应南移至南部地表分水岭一带。蒙自盆地及南部地下水流向应整体由南向北。 相似文献
14.
在详细调查基础上，采用系统科学及水文地质分析方法，依据地形地貌、地层岩性、地质构造、示踪试验、地下水排泄基准面、喀斯特发育条件及发育规律等剖析论证流域边界，并通过钻探及示踪试验进行验证。研究结果:（1）对泸西喀斯特断陷盆地南东部的水系统边界向北移进行了修正，证实了三塘一带深部不发育的喀斯特是地下水分水岭边界，使得泸西喀斯特断陷盆地流域的径流系统和边界圈化更加准确；（2）泸西喀斯特断陷盆地流域地表水、地下水转化频繁，地表水径流特征主要以小江河在水库、河流、伏流间的径流转化过程为体现，地下水在侵溶山区接受大气降水补给后，上层径流以泉、暗河的形式在泸西盆地底面排泄后转化成地表水，最终汇集于盆地南部、通过工农隧洞及落水洞排向小江，而下层径流则以小江水面为基准，通过深层径流排泄。 相似文献
15.
A distributed water-heat coupled model for mountainous watershed of an inland river basin of Northwest China (I) model structure and equations 总被引：1，自引：0，他引：1
Ren-sheng Chen Shi-hua Lu Er-si Kang Xi-bin Ji Zhihui Zhang Yong Yang Wenwu Qing 《Environmental Geology》2008,53(6):1299-1309
It is absolutely necessary to quantify the hydrological processes in earth surface by numerical models in the cold regions
where although most Chinese large rivers acquire their headstreams, due to global warming, its glacier, permafrost and snow
cover have degraded seriously in the recent 50 years. Especially in an arid inland river basin, where the main water resources
come from mountainous watershed, it becomes an urgent case. However, frozen ground’s impact to water cycle is little considered
in the distributed hydrological models for a watershed. Took Heihe mountainous watershed with an area of 10,009 km2, as an example, the authors designed a distributed heat-water coupled (DWHC) model by referring to SHAW and COUP. The DWHC
model includes meteorological variable interception model, vegetation interception model, snow and glacier melting model,
soil water-heat coupled model, evapotransporation model, runoff generation model, infiltration model and flow concentration
model. With 1 km DTM grids in daily scale, the DWHC model describes the basic hydrological processes in the research watershed,
with 3∼5 soil layers for each of the 18 soil types, 9 vegetation types and 11 landuse types, according to the field measurements,
remote sensing data and some previous research results. The model can compute the continuous equation of heat and water flow
in the soil and can estimate them continuously, by numerical methods or by some empirical formula, which depends on freezing
soil status. However, the model still has some conceptual parameters, and need to be improved in the future. This paper describes
only the model structure and basic equations, whereas in the next papers, the model calibration results using the data measured
at meteorological stations, together with Mesoscale Model version 5 (MM5) outputs, will be further introduced. 相似文献
16.
LESZEK MARKS IRINA E. PAVLOVSKAYA 《Boreas: An International Journal of Quaternary Research》2003,32(2):337-346
The Holsteinian drainage system in mid-eastern Poland and western Belarus has been reconstructed using palaeogeographical analysis based on abundant boreholes. The stratigraphic setting and palaeogeography are determined by correlation with Holsteinian marine sediments in the Kaliningrad District of Russia and the Late Elsterian glaciolacustrine series in the southern peribaltic region. At the beginning of the Holsteinian there were numerous residual overflow lakes at the Polish-Belarusian border area that gradually became interconnected with the Holsteinian Neman River and its tributaries. The base level of erosion is located in river beds of Holsteinian valleys slightly beneath beds of the recent rivers and indicates that Holsteinian sea level was apparently lower than the present Baltic Sea level. The Holsteinian Neman flowed southwestwards across the Biebrza River Basin to the Warsaw Basin. The main watershed between the Baltic Sea and the Black Sea was further to the west than its present location. The secondary watershed in northern Poland has only been slightly modified since that time. 相似文献
17.
The changes in the water chemistry of rivers can reflect influence of anthropogenic activities on the water environment to
some extent. To understand the relationship between the spatial distribution of the eco-environment of the watershed and the
characteristics of water chemistry and geochemistry of rivers, firstly, the digital Wujiang watershed was built, and then
the sub-watersheds were delineated, taking the sample points as sub-watershed outlets based on GIS. Secondly, using the function
of spatial analyst of GIS, the statistical features of eco-environment (such as lithology and land use/cover) of each sub-watershed
were calculated according to their respective classification. Finally, the correlation between the spatial distribution of
lithology of the sub-watersheds and their corresponding 87Sr/86Sr ratio of river water, the correlation between NO3
−/HCO3
−, Cl−/HCO3
−, SO4
2−/HCO3
− and anthropogenic activities, respectively, and the correlation between the fraction of green vegetation of the sub-watershed
and their corresponding flux of TDS (total dissolved solids) were analyzed quantitatively. The results justify that the 87Sr/86Sr ratio of river water is highly dependent on the lithologic feature of the watershed and indicate that anthropogenic activities
are one of the main sources of NO3
− and SO4
2− of river waters. The output of TDS is highly dependent on the percentage of vegetation cover of the watershed. 相似文献
18.
Tom Myers 《Hydrogeology Journal》2013,21(3):655-671
Extensive phosphate mining in the Blackfoot watershed of Idaho (USA) has substantially increased the selenium (Se) concentration in the river during both snowmelt and baseflow when groundwater discharge dominates. Phosphate mines create a linkage between Se-laden shale that occurs in the Phosphoria Formation and the underlying regional Wells Formation aquifer. Using a reconnaissance-level transport model, mines in the watershed were prioritized for remediation and for comparing the results of simulations of remediation scenarios with a baseline of no remediation, for which Se concentration in the river will exceed the aquatic standard along an extensive length. An accurate simulation of recharge distribution around the watershed and simulated flux to the river is essential. Remediation of mines north of the river will substantially decrease the size of the Se plume, although significant Se will continue to discharge to the river. Similarly, remediation of three mines south of the river would decrease the Se discharge to the river but allow substantial amounts to remain stored in the groundwater north and far south of the river. A lack of calibration data is not a reason to forgo remediation, but rather ongoing data collection can be used to fine-tune plans as they are implemented. 相似文献
19.
Recognition of the degraded state of rivers across the world has prompted the development of management programmes which promote river repair through rehabilitation practices. Efforts to date have emphasised concerns for biophysical attributes of rivers to the relative exclusion of socio-cultural values. Ultimately, the process of river repair must move beyond this technical focus and incorporate collective societal engagement, participation and ownership. However, the inherent complexities of informing and managing this process limit the prospects that engagement will be translated into an effective and sustained practice. This qualitative case study research analyses the community’s knowledge, views and opinions regarding geomorphic river change and river works projects undertaken in the Upper Hunter catchment, New South Wales, Australia. The responses and views expressed by the participants highlight how ineffective communication and limited understanding of past river work practices has inhibited the connection and ownership between the people and their river. Essentially, historical river management was viewed as a technical process that failed to incorporate social values and aspirations, and which gave inadequate consideration to local knowledge and experience. Participants identified the need to address both diversity and commonality in vision-building and the need for greater confidence and transparency in river science and management. In light of these responses, this paper argues for the adoption of a geo-social, transdisciplinary approach to river rehabilitation. 相似文献
20.
The role of hydrology in annual organic carbon loads and terrestrial organic matter export from a midwestern agricultural watershed 总被引：1，自引：0，他引：1
Brent J. Dalzell Timothy R. Filley Jon M. Harbor 《Geochimica et cosmochimica acta》2007,71(6):1448-1462
Defining the control that hydrology exerts on organic carbon (OC) export at the watershed scale is important for understanding how the source and quantity of OC in streams and rivers is influenced by climate change or by landscape drainage. To this end, molecular (lignin phenol), stable carbon isotope, and dissolved organic carbon (DOC) data were collected over a range of flow conditions to examine the influence of hydrology on annual OC export from an 850 km2 Midwestern United States agricultural watershed located in west central Indiana. In years 2002 and 2003, modeled annual DOC loads were 19.5 and 14.1 kg ha−1yr−1, while 71% and 85%, respectively, of the total annual OC was exported in flow events occurring during less than 20% of that time. These results highlight the importance of short-duration, high-discharge events (common in smaller watersheds) in controlling annual OC export. Based on reported increases in annual stream discharge coupled with current estimates of DOC export, annual DOC loads in this watershed may have increased by up to 40% over the past 50 years. Molecular (lignin phenol) characterization of quantity and relative degradation state of terrestrial OC shows as much temporal variability of lignin parameters (in high molecular weight dissolved organic carbon) in this one watershed as that demonstrated in previously published studies of dissolved organic matter in the Mississippi and Amazon Rivers. These results suggest that hydrologic variability is at least as important in determining the nature and extent of OC export as geographic variability. Moreover, molecular and bulk stable carbon isotope data from high molecular weight dissolved organic carbon and colloidal organic carbon showed that increased stream flow from the study watershed was responsible for increased export of agriculturally derived OC. When considered in the context of results from other studies that show the importance of flood events and in-stream processing of terrestrial organic carbon, our results show how hydrologic variability in smaller watersheds can reflect landscape-scale carbon dynamics in ways that cannot necessarily be measured at the outlets of large rivers due to multiple source signals and attenuated hydrology. 相似文献