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1.
两种自动基流分割方法在干旱半干旱地区的对比研究 总被引：1，自引：0，他引：1
基流是河川径流的重要组成部分。在干旱半干旱地区,基流对于维持水源的稳定性及持续性、确定河流生态需水等方面具有重要作用。因此,基流分割结果的准确性至关重要。本文以黄河流域上游小流域为研究区,分别使用滑动最小值法和数字滤波法对典型年进行基流分割,然后用数字滤波法对1980-2014年日均径流进行基流分割,并分析基流的变化趋势。研究表明,数字滤波法在干旱半干旱地区具有较好的应用效果,滑动最小值法分割的基流结果偏小;在特定研究区的参数难以确定时,应结合两种方法的优点确定最佳的基流分割方案。研究区1980-2014年的平均基流指数为0.69,高于全国平均值0.26、西北诸河区的0.57及黄河区的0.43;趋势分析显示,研究区的年径流、基流、BFI的增长幅度分别为0.086 (m3/s)/10a、0.169 (m3/s)/10a、0.038/10a。MK趋势检验结果显示,年径流未通过10%的显著性检验,增长趋势不明显;基流和BFI分别通过了2.5%和1%的显著性检验,增长趋势显著。 相似文献
2.
基于数字滤波法和SWAT模型的灞河流域基流时空变化特征研究 总被引：1，自引：0，他引：1
将国内外应用较广的数字滤波法和分布式水文模型SWAT相结合,在进行基流时间特征分析的基础上,通过修正基流退水系数α、模型效率评价、重新运行模型、GIS空间插值和趋势分析等方法,创新性地实现了基流空间特征的可视化表达。研究结果表明：① 2001~2012年灞河流域年均基流指数（BFI）为0.43,总体呈增加的趋势。年降水量与年径流、年基流均呈明显的正相关关系,与年基流指数呈明显的负相关关系;② 基流年内变化较为稳定,在时间上存在秋季>春季>夏季>冬季、汛期>非汛期的关系。枯水期的基流指数高达0.78,表明基流是枯水期河流的主要补给来源;③ 灞河流域基流在空间上表现为自东南向西北、自上游向下游逐渐增加的趋势,这种空间分异规律是由流域的地势和河流流向决定的。 相似文献
3.
研究和确定流域生态基流及天然植被需水量是为了遏制因河道断流或流量减少而造成的生态环境退化,以确保流域生态系统健康发展。根据孔雀河流域植被类型分布及多年径流状况,将河道分为A、B两部分,A段为孔雀河上游塔什店至第三分水枢纽常年未断流河道;B段为第三分水枢纽以下天然植被主要分布区。基于塔什店水文站近50 a水文数据,结合Tennant法等4种方法对A段河道生态基流进行估算;选择潜水蒸发法、定额法对B段距河道1 km辐射范围内的天然植被需水量进行计算。结果表明:Tennant法估算的年均生态基流为9.13 m3·s-1,对应基本生态水量为2.88×108 m3·a-1,满足A段河道2000—2018年多年平均河损,且近10 a(2009—2018年)塔什店实测年均流量均可满足此生态基流标准;B段河道辐射范围内天然植被总面积为4.66×104 hm2,生态需水量为0.95×108 m3·a-1,以孔雀河生态输水工程为例科学调控水资源,在满足A段基本生态基流的同时兼顾B段天然植被需水量。研究结果对实现孔雀河河道修复和不同水平年下生态供水具有一定的意义。 相似文献
4.
黄河源区基流估算 总被引：10，自引：1，他引：10
河川基流在水安全、粮食安全、非点源污染评价、水资源评价和调查、水资源配置、工农业供水和降雨-径流关系模拟中有着重要的应用。黄河源区(唐乃亥水文站以上区域)的产水量占黄河流域的35%以上,是黄河流域的重要产水区,对黄河源区基流的估算就显得尤为重要。根据研究区域的气候特征,对加里宁法在本区域的应用提出了改进,并提出了新的计算程序。在此基础上,和电子滤波法进行了对比分析。结果表明,电子滤波法非常敏感,滤波参数β控制了基流在总径流中的比例,β与基流成负相关关系,对于不同的来水年份,其敏感性分析图形的形态都很相似;改进的加里宁法基流划分过程强烈地依赖于日过程线的起伏情况,基流一般随着退水系数的增加而增大,加里宁法分割的基流对于参数的变化并不敏感。 相似文献
5.
呼图壁河基流变化及其影响因素 总被引：2，自引：1，他引：1
基于石门水文站实测日径流数据和流域气象资料,运用平滑最小值法和递归数字滤波法对呼图壁河流量过程进行了基流分割研究。在不同的时间尺度上探讨了呼图壁河年均基流量和基流指数（BFI）的变化特征,以及不同水平年基流量与BFI的变化特征,并按照不同水平年份的划分从气温和降水两方面剖析影响基流变化的因素。结果表明：研究区内平滑最小值法优于递归数字滤波法。呼图壁河基流量的年内分布表现为单峰型,7月达到最大值,BFI先减小后增加,5月最小,枯水期BFI接近1。呼图壁河年基流量呈现为增加的趋势,多年平均基流量为3.67×108 m3,多年平均BFI为0.78,呈递减趋势。枯水年份的平均BFI为0.78,平水年为0.76,丰水年为0.74。春秋两季气温和降水对呼图壁河基流量的影响最为显著,不同的水平年份相关系数也存在一定差异。各年份气温对春秋两季基流量的影响均大于降水,说明气温是呼图壁河基流变化的关键性因素。 相似文献
6.
2005年12月中、下旬对松花江哈达湾至佳木斯江段冰封期江水和沉积物进行了采样与分析。结果表明,江水总汞质量浓度为29.74~136.88 ng/L,均值为50.21 ng/L,以悬浮颗粒态为主(53.38%~85.99%)。沉积物总汞的质量分数介于0.013~1.543 mg/kg之间,与铁、锰和有机碳含量呈显著正相关;运用连续化学浸提法,对哨口至松原江段沉积物汞的形态进行了分析,沉积物汞主要以碱溶态、强有机质结合态和残渣态存在,可交换态和盐酸溶态汞的比例较小,仅占总汞的0.91%~33.7%。研究发现,沉积物再悬浮作用是影响松花江冰封期江水悬浮颗粒态汞及总汞空间分布的主要因子,沉积物汞释放是一个缓慢长期的过程。 相似文献
7.
Based on the continuous monitoring data of hydrology and water quality in the period from 1972 to 1997, the responses of hydro-environment system to melt water in the Second Songhua River basin were derived. Because of melt water, the water quality in the Second Songhua River is good and changes very except that the contents of Hg and Mn in the water are higher. The contribution of melt water to the water fluxes in the Second Songhua River basin is distinct: the water flow in April increases remarkably, reaches the peak in the upper reaches. The pollutant contributions and water pollution indices (WPIs) of the Second Songhua River in April are high in the upper reaches while that in the lower reaches are low. The responses of hydro-environment system to melt water of that basin are affected by content of packed snow and the underlining surface systems. 相似文献
8.
Based on the continuous monitoring data of hydrology and water quality in the period from 1972 to 1997, the responses of hydro-environment system to melt water in the Second Songhua River basin were derived. Because of melt water, the water quality in the Second Songhua River is good and changes very except that the contents of Hg and Mn in the water are higher. The contribution of melt water to the water fluxes in the Second Songhua River basin is distinct: the water flow in April increases remarkably, reaches the peak in the upper reaches. The pollutant contributions and water pollution indices (WPIs) of the Second Songhua River in April are high in the upper reaches while that in the lower reaches are low. The responses of hydro-environment system to melt water of that basin are affected by content of packed snow and the underlining surface systems. 相似文献
9.
Based on the continuous monitoring data of hydrology and water quality in the period from 1972 to 1997, the responses of hydro-environment
system to melt water in the Second Songhua River basin were derived. Because of melt water, the water quality in the Second
Songhua River is good and changes very except that the contents of Hg and Mn in the water are higher. The contribution of
melt water to the water fluxes in the Second Songhua River basin is distinct: the water flow in April increases remarkably,
reaches the peak in the upper reaches. The pollutant contributions and water pollution indices (WPIs) of the Second Songhua
River in April are high in the upper reaches while that in the lower reaches are low. The responses of hydro-environment system
to melt water of that basin are affected by content of packed snow and the underlining surface systems. 相似文献
10.
ZHANG Lei WANG Qi-Chao SHAO Zhi-Guo 《湿地科学》2005,3(1):27-31
1 INTRODUCTIONIntherecentyears,exposuretoenvironmentaltoxinshasreceivedincreasingattentionasthepublicadverseeffectcausedbytheirtoxicity .Mercuryisoneofmosttoxicmetalsintheworld .Manyre searcheshaveprovedthattheconsumptionoffishesmercurypollutedisthemains… 相似文献
11.
Groundwater control on the suspended sediment load in the Na Borges River, Mallorca, Spain 总被引：1，自引：0，他引：1
Groundwater dominance has important effects on the hydrological and geomorphological characteristics of river systems. Low suspended sediment concentrations and high water clarity are expected because significant inputs of sediment-free spring water dilute the suspended sediment generated by storms. However, in many Mediterranean rivers, groundwater dominance is characterised by seasonal alternations of influent and effluent discharge involving significant variability on the sediment transport regimes. Such areas are often subject to soil and water conservation practices over the centuries that have reduced the sediment contribution from agricultural fields and favour subsurface flow to rivers. Moreover, urbanisation during the twentieth century has changed the catchment hydrology and altered basic river processes due to its ‘flashy’ regime. In this context, we monitored suspended sediment fluxes during a two-year period in the Na Borges River, a lowland agricultural catchment (319 km2) on the island of Mallorca (Balearic Islands). The suspended sediment concentration (SSC) was lower when the base flow index (i.e., relative proportion of baseflow compared to stormflow, BFI) was higher. Therefore, strong seasonal contrasts explain the high SSC coefficient of variation, which is clearly related to dilution effects associated with different groundwater and surface water seasonal interactions. A lack of correlation in the Q-SSC rating curves shows that factors other than discharge control sediment transport. As a result, at the event scale, multiple regressions illustrate that groundwater and surface water interactions are involved in the sedimentary response of flood events. In the winter, the stability of baseflow driven by groundwater contributions and agricultural and urban spills causes hydraulic variables (i.e., maximum discharge) to exert the most important control on events, whereas in the summer, it is necessary to accumulate important volumes of rainfall, creating a minimum of wet conditions in the catchment to activate hydrological pathways and deliver sediment to the drainage network. The BFI is also related to sediment delivery processes, as the loads are higher with lower BFI, corroborating the fact that most sediment movement is caused by stormflow and its related factors. Overall, suspended sediment yields were very low (i.e., < 1 t km− 2 yr− 1) at all measuring sites. Such values are the consequence of the limited sediment delivery attributable to soil conservation practices, low surface runoff coefficients and specific geomorphic features of groundwater-dominated rivers, such as low drainage density, low gradient, steep valley walls and flat valley floors. 相似文献
12.
怒江流域悬移质输沙时空分布特征及变化趋势 总被引：1，自引：0，他引：1
利用怒江-萨尔温江上游地区怒江流域5 个水文站长序列日悬移质输沙与径流观测记录,运用Mann-Kendall 检验和R/S 分析等方法,分析了50 多年来(1956-2011) 怒江干流和支流南汀河输沙时空格局和变化特征及其与径流的关系.结果表明：(1) 怒江干流平均含沙量和输沙模数远小于支流南汀河,流域悬移质输沙率年际变异系数随控制面积增大而减小;(2) 怒江干流木城站悬移质输沙率小于其上游道街坝站,部分泥沙淤积在区间河床可能是其原因之一;(3) 怒江流域悬移质输沙年内分配极不均匀,干流悬移质输沙集中程度在月以上时间尺度高于支流南汀河,而在日时间尺度则低于支流南汀河;(4) 怒江干流和支流南汀河悬移质输沙率均呈明显上升趋势,且未来仍将延续上升趋势,二者的突变分别始于1987 年和1980 年;(5) 怒江干流中上游悬移质输沙与径流的相关性不显著,中下游、下游以及支流南汀河悬移质输沙与径流的相关性均显著. 相似文献
13.
水质恢复能力评价方法及其在黄河流域的应用 总被引：4，自引：0，他引：4
在探讨水体水质恢复途径的基础上,建立了水质恢复能力评价标准和方法。根据黄河干流1998年的纳污情况及河水中三类主要污染物 (BOD、氨氮和挥发酚) 的浓度对黄河干流的水质恢复能力进行了评价,发现对于单位河长,除潼关-三门峡河段水质恢复能力属中等以外,其余河段水质恢复能力均较弱。物理稀释作用对水相中污染物浓度降低的贡献相对较小;各河段的水质恢复能力与泥沙含量呈显著正相关,与水温呈一定程度的正相关。黄河干流这种较差的水质恢复能力表明黄河干流的环境功能较弱,且现有的污染物排放已经超过了其水质恢复的能力,从而致使水质恶化,影响水资源的可持续利用。 相似文献
14.
Spatial and temporal change in the potential evapotranspiration sensitivity to meteorological factors in China (1960?2007) 总被引：3，自引：0，他引：3
Potential evapotranspiration (E0), as an estimate of the evaporative demand of the atmosphere, has been widely studied in the fields of irrigation management, crop water demand and predictions in ungauged basins (PUBs). Analysis of the sensitivity of E0 to meteorological factors is a basic research on the impact of climate change on water resources, and also is important to the optimal allocation of agricultural water resources. This paper dealt with sensitivity of E0 over China, which was divided into ten drainage systems, including Songhua River basin, Liaohe River basin, Haihe River basin, Yellow River basin, Yangtze River basin, Pearl River basin, Huaihe River drainage system, Southeast river drainage system, Northwest river drainage system and Southwest river drainage system. In addition, the calculation method of global radiation in Penman-Monteith formula was improved by optimization, and the sensitivities of Penman-Monteith potential evapotranspiration to the daily maximum temperature (STmax), daily minimum temperature (STmin), wind speed (SU2), global radiation (SRs) and vapor pressure (SVP) were calculated and analyzed based on the long-term meteorological data from 653 meteorological stations in China during the period 1960-2007. Results show that: (1) the correlation coefficient between E0 and pan evaporation increased from 0.61 to 0.75. E0 had the decline trends in eight of ten drainage systems in China, which indicates that “pan evaporation paradox” commonly exists in China from 1960 to 2007. (2) Spatially, Tmax was the most sensitive factor in Haihe River basin, Yellow River basin, Huaihe River drainage system, Yangtze River basin, Pearl River basin and Southeast river drainage system, and VP was the most sensitive factor in Songhua River Basin, Liaohe River basin, Northwest river drainage system while Rs was the most sensitive factor in Southwest river drainage system. For the nation-wide average, the most sensitive factor was VP, followed by Tmax, Rs, U2 and Tmin. In addition, the changes in sensitivity coefficients had a certain correlation with elevation. (3) Temporally, the maximum values of STmax and SRs occurred in July, while the maximum values of STmin, SVP and SU2 occurred in January. Moreover, trend analysis indicates that STmax had decline trends, while STmin, SU2, SRs and SVP had increasing 相似文献
15.
基于SWAT模型的基流估算及评价——以洛河流域为例 总被引：65，自引：1，他引：65
SWAT是一个具有很强物理机制的长时段的流域分布式水文模型,它能够利用GIS和RS提供的空间数据信息,模拟复杂大流域中的径流成分。本文应用SWAT模型对基流进行模拟,分别采用1992～1996年和1997～1998年洛河流域卢氏水文站逐年、月实测径流资料进行模型校准和验证,确定模型的敏感性参数:径流曲线数、地下水再蒸发系数、土壤蒸发补偿系数和植物蒸发补偿系数;并借助滤波技术对实测径流进行基流分割。将滤波分割的基流与SWAT模拟值进行对比,采用线性回归系数(R2)和Nash-Suttclife模拟系数(Ens)对SWAT模型进行评价,其结果月基流R2为0.76,Ens为0.75,模拟精度较高。 相似文献
16.
效率演化视角下吉林省松花江流域产业系统环境适应性研究 总被引：3，自引：0，他引：3
基于效率演化视角与适应性分析范式,综合采用投入导向生产规模报酬可变的VRS模型,对吉林省松花江流域产业系统环境适应性时空分异特征与影响因素进行了研究,结果发现松花江流域产业系统：① 现状格局特征分析反映出吉林省松花江流域各县市尚处于规模扩张与总量增长阶段,仍有众多县市尚未达到最优规模阶段,在未来一段时间内,规模集聚仍是产业或经济发展的主流;② 时序演化特征分析反映出吉林省松花江流域产业生态化发展迟缓,产业规模扩张仍是效率提升的关键所在,科学技术尚未发挥出其应有作用;③ 空间分异特征分析,综合效率与规模效率较高的县市不断向流域中上游地区聚集,纯技术效率主要集中于中下游地区,综合效率的提升主要由于规模效率的增加,纯技术效率对其作用不明显;④ 区位条件、路径依赖效应、经济发展水平以及科学技术因素是影响吉林省松花江流域产业系统环境适应性的重要因素。 相似文献
17.
哈达山水利枢纽对第二松花江下游地区汞污染的影响 总被引：1，自引：0，他引：1
通过调查第二松花江10个典型断面沉积物、江水中总汞及江水中不同形态的汞浓度,研究了建坝对于库区汞污染的影响。建坝之后,由于水文条件改变,悬移质发生沉降,库区沉积物中汞浓度将会增加,库区会变成汞的汇。库区下游出水处江水汞浓度将降低至0.032 μg/L。每年通过推移质输沙向库区输入约4.37 kg汞,通过悬移质输沙向库区输入约856.8 kg汞。由于输沙的影响,每年将会在库区形成厚约1.23 cm的沉积物。库区上游沉积物的再悬浮、水库淹没区汞的溶出,对库区汞通量影响不大。 相似文献
18.
我国河水主要离子组成与区域自然条件的关系 总被引：18，自引：2，他引：16
对我国四大水系－长江、黄河、松花江和珠江５０年代末至８０年代中期河水中主要离子含量流域降水量、区域地质岩性等自然条件进行了统计研究。研究表明：区域地质岩性对河水离子含量和组成有显著影响;河水离子总量与相应区域的降水存在显著负相关关系。 相似文献
19.
CHAI Yuanfang YANG Yunping DENG Jinyun SUN Zhaohua LI Yitian ZHU Lingling 《地理学报(英文版)》2020,30(10):1633-1648
The operation of large-scale reservoirs have modified water and sediment transport processes, resulting in adjustments to the river topography and water levels. The polynomial fitting method was applied to analyze the variation characteristics of water levels under different water discharge values in the Jingjiang reach of the Yangtze River from 1991–2016. The segregation variable method was used to estimate the contributions of the varied riverbed evaluation, the downstream-controlled water level, and the comprehensive roughness on the altered water level at an identical flow. We find that low water levels in the Jingjiang reach of the Yangtze River from 1991–2016 are characterized by a significant downward trend, which has intensified since 2009. Riverbed scouring has been the dominate factor causing the reduced low water level while increased roughness alleviated this reduction. From 1991–2016, there was first a decrease followed by an increase in the high water level. The variation characteristic in terms of the "high flood discharge at a high water level" before 2003 transformed into a "middle flood discharge at a high water level" since 2009. The increased comprehensive roughness was the main reason for the increased high water level, where river scouring alleviated this rise. For navigation conditions and flood control, intensified riverbed scouring of the sandy reaches downstream from dams enhanced the effects that the downstream water level has on the upstream water level. This has led to an insufficient water depth in the reaches below the dams, which should receive immediate attention. The alteredvariation characteristics of the high water level have also increased the flood pressure in the middle reaches of the Yangtze River. 相似文献
20.
水库运行改变了坝下游水沙输移条件,在河道冲刷的同时,引起水位过程出现适应性调整。本文以长江中游荆江河段为对象,采用多项式拟合法,对比分析1991—2016年间分级流量—水位变化特征,采用基于河流动力学原理的分离变量法,识别河道冲淤、下游控制水位及河床综合糙率等变化对分级流量—水位变化的影响程度。研究表明：1991—2016年间,长江中游荆江河段同流量—枯水位呈下降趋势,2009年以来降幅增大;河道冲刷是引起同流量—枯水位下降的主控因素,河床综合糙率增加抑制了同流量—枯水位下降起到积极作用。1991—2016年间,荆江河段同流量—洪水位经历了先减小后增大的“凹”线型变化,2003年以前洪水特征为“高洪水流量—高水位”,2009年以来逐渐演化为“中大洪水流量—高水位”,同流量—洪水位特性发生转变;河床综合糙率增大是同流量—洪水位抬升的主控因素,河道冲刷抑制了同流量—洪水位的抬升态势。在航道条件及防洪情势上,应重点防控近坝段沙质河段冲刷引起的水位下降溯源传递作用,其洪水流量—水位特性的转变,不利于减缓荆江河段的防洪压力。 相似文献