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1.
洞庭湖与长江水体交换能力演变及对三峡水库运行的响应 总被引：6，自引：0，他引：6
运用洞庭湖区与长江干流相关控制站1951-2010 年实测水文数据, 在分析江湖水力关系的基础上, 从不同时间尺度分析江湖水体交换能力的演变特征及其对三峡水库运行的响应。结果表明:① 7-9 月长江荆南三口对洞庭湖的补给能力较强, 1-3 月洞庭湖对长江的补给能力较强;② 江湖水体交换系数具有明显的年代际波动, 其中1951-1958 年、1959-1968 年荆南三口对湖泊的补给能力较强, 而2003-2010 年湖泊对长江的补给能力增强;③ 三峡水库运行后无论是典型年还是在水库不同调度方式运行期, 三口分泄能力减弱, 入湖水量减少, 而因四水入湖水量占绝对优势, 湖泊对长江的补给能力明显增强;④ 尽管影响江湖水体交换能力的因素极为复杂, 但从总体上讲, 除受流域降水波动影响外, 江湖水体交换能力在不同时间尺度上的演变特征及其过程均随着江湖水体交换量的变化而变化, 说明江湖水体交换能力强度与江湖水体交换量之间存在着彼此消长的关系。 相似文献
2.
三峡水库运行下洞庭湖盆冲淤过程响应与水沙调控阈值 总被引：4，自引：0，他引：4
以1951-2011 年洞庭湖区及荆江段干流主要控制站实测径流输沙量资料为依据,分析三峡水库不同蓄水阶段及不同调度方式下洞庭湖盆冲/淤响应,并提出上游来水来沙调控阈值。结果表明：① 荆南三（四）口流量与枝城站流量、荆南三（四）口输沙率存在极显著正相关（p < 0.0001）,决定系数r2分别为0.859 及0.895。② 与三峡水库蓄水运用前（1999-2002）相比,一、二期蓄水阶段及全面试验性蓄水阶段（2008.10-2011.12）洞庭湖盆年均冲淤量由+4796.4×104 t 依次递减为+684.1×104 t、+449.8×104 t 及-559.6×104 t,湖盆冲淤率由+70.25%分别降至+31.13%、+23.56%及-42.64%。③ 预泄调度及蓄水调度期,湖盆泥沙均由以淤积为主转变为以冲刷为主,防洪补偿调度期湖盆泥沙表现为淤积,而在补水调度运用期则表现为冲刷。④ 洞庭湖盆处于冲/淤临界平衡状态时的荆南三口平均流量、输沙率及含沙量分别为970.81 m3/s、466.82 kg/s 及0.481 kg/m3。并认为,为增强湖泊调蓄功能,必须进一步优化三峡水库调度方式,合理调控下泄水沙量。 相似文献
3.
三峡水库不同调度方式运行期洞庭湖区的水情响应 总被引：4，自引：0，他引：4
运用1951-2002 年典型年实测原型水文资料,对比分析2003-2010 年三峡水库不同调度方式运行期对洞庭湖区水情的影响,结果表明：(1) 影响时间为每年5 月25 日-6 月10 日、7 月1 日-8月31 日、9 月15 日-10 月31 日、12 月-次年4 月,其中枯期补水调度的影响不很敏感;(2) 预泄调度,平水年径流有所增加,平均水位、最高水位均有上升。丰、枯年影响期径流增加平均值40.25 ×108 m3;平均水位抬高平均值1.06 m,最高水位壅高平均值1.06 m;(3) 蓄洪调度,平水年洪水量稍有上涨,枯、丰年影响期洪水减少平均值444.02 × 108 m3,平均洪水位降低平均值2.64 m,最高洪水位降低平均值1.42 m;(4) 蓄水调度,除平水年影响期径流增加、水位稍有壅高外,枯、丰年影响期径流减少平均值185.27 × 108 m3,平均水位降低平均值3.13 m,最高水位降低平均值2.14 m;(5) 补水调度,平、丰年影响期径流减少平均值337.7 × 108 m3,平均水位降低平均值1.89 m,最高水位降低平均值2.39 m,但枯水年影响期径流量增加、平均水位与最高水位稍有抬高。关键词：长江三峡水库;调度方式;洞庭湖区;水情变化 相似文献
4.
近10 年来长江口水下三角洲的冲淤变化 ——-兼论三峡工程蓄水的影响 总被引：4，自引：0，他引：4
根据对近10 年来长江入海泥沙量和河口冲淤的对比分析, 探讨水下三角洲冲淤对长江入海泥沙锐减以及三峡工程运行的响应。结果表明: (1) 三峡水库蓄水导致长江入海泥沙减少1×108 t/a 量级; (2) 1995-2000 年、2000-2004 年和2004-2005 年研究区淤积(冲刷) 面积分别占75.5% (24.5%)、30.5% (69.5%) 和14% (86%), 垂向冲淤速率(负为冲刷) 分别为6.4 cm/a、-3.8 cm/a 和-21 cm/a。(3) 由于地形和水动力的变化以及工程的影响, 研究区内冲淤对河流来沙减少的响应存在显著空间差异。结论包括: 三峡水库蓄水加剧了长江入海泥沙的减少; 入海泥沙的锐减是水下三角洲从淤积为主向侵蚀为主转变的主要原因。随着水库拦沙能力的增强等流域人类活动的影响, 长江入海泥沙将进一步下降, 河口口门区的冲刷可能加剧, 值得有关部门重视。 相似文献
5.
洞庭湖环境系统变化对水文情势的响应 总被引：11，自引：2，他引：9
为全面揭示洞庭湖近数十年的水情异常与成因,将湖区视作一个大系统来研究。经水位~流量关系等多种方法研究表明：(1)入湖四水尾闾同水位流量减少1 200~2 800 m3/s,同流量水位抬高0.49~1.28 m;(2) 荆江三口分水比减少19.2%,分沙比减少25.1%;(3) 澧水、松滋、南洞庭湖等主洪道的水位流量关系均发生了较大变化;(4) 天然调蓄能力下降40%,湖口同流量水位抬高1.80~2.50 m;(5) 7~8月湖垸关系常处于危急状态。其主要原因是泥沙淤积恶性循环,导致了湖泊环境系统功能的变化,而由下荆江3处裁弯所引起的江湖水沙调整则加速了其变化过程。这些变化过程对水情的复合响应是：入湖水沙呈逐渐减少趋势变化,洪水位普遍抬高1.50~1.80 m,湖口有时出现江水倒流,洪水涨率增大,高洪水位持续时间长等异常水文现象,且给湖区造成了巨大的洪水压力。 相似文献
6.
上荆江枯水位对河床冲刷及水库调度的综合响应 总被引：2，自引：0，他引：2
为系统揭示长江中游近期枯水情势及其对三峡水库蓄水的直接和间接响应,本文以冲刷剧烈、枯水位降幅最大的上荆江为例,通过统计其不同形式枯水位的变化特征,建立了水位下降与河床冲刷、水库不同运行方式的相关关系。结果表明,沙市站同流量枯水位几乎与枯水河槽河床平均高程等幅下降,枝城站枯水位下降幅度较小与本底河床形态、河床粗化及航道整治工程有关。上荆江汛前枯水位降幅、最低水位及极枯水位历时等枯水情势会受到三峡水库补水调度的影响,这种补水效应沿程递减,至沙市站补水调度仍然无法抵消河床下切对枯水位造成的影响。 相似文献
7.
鄱阳湖与长江之间存在着复杂的相互作用关系,决定着江湖水沙交换,对整个区域的水资源、防洪、航运、生态环境等均具有重要影响。本文基于能量的观点,在从新的角度解释鄱阳湖和长江相互作用原理的基础上,构建了江湖相互作用的表征指标—能差Fe,对20世纪50年代以来江湖作用关系变化进行了研究。结果表明,自20世纪50年代以来,Fe值整体呈现增加趋势,说明长江作用减弱,鄱阳湖作用不断增强。三峡水库蓄水运用对江湖关系产生了重要影响,进一步削弱了长江作用。从年内变化来看,由于三峡水库的调节,枯水期长江作用略有增强,汛末长江作用减弱较大。江湖作用一定程度上影响着湖区旱涝灾害的产生,当五河来流较大且长江顶托作用明显时,易发生洪涝;当五河来流较小但又对长江有明显的补水作用时,易发生旱情,三峡水库蓄水使湖区9-10月更易发生干旱。 相似文献
8.
<正>三峡电站全年发电量创造了新的世界纪录。中国长江三峡集团公司于2015年1月1日宣布,截至2014年12月31日24时,三峡电站全年发电量达988亿千瓦时,创单座水电站年发电量新的世界纪录。2014年度,三峡水库来水量比多年平均偏枯2.8%,三峡电厂坚持精益管理,不断提高监测水平,调整设备运行方式,加强安全管理和隐患排查,强化电站设备状态分析与评估,科学制定年度检修计划,使机组运行工况达到最优,始终处于安全稳定状态,为机组满发多发创造了良好条件。去年,长江电力三峡梯调中心着力强化了流域水雨情预报和发电计划制作能力,通过开展四库联合调度,合理安排检修计划和运行方式,充分发 相似文献
9.
长江三角洲前缘近十余年的冲淤演变及工程影响研究 总被引：1，自引：0，他引：1
杜景龙 《地理与地理信息科学》2012,28(5):80-85,113
根据1994-2008年国家专业部门测量的长江口口门区水下地形图及相关数据资料,分析了长江河口三角洲近十余年的冲淤过程:1)在长江来沙显著减少的背景下,三角洲出现了由淤到冲的转换,1994-2000年、2000-2008年,长江口门研究区(1 500 km2)净淤积量分别为7.25亿m3(1.21亿m3/a)和-1.23亿m3(-0.15亿m3/a),冲淤转换的临界输沙率约为2.97亿t(大通站).冲淤转换的时间大约发生在2000-2002年;2)三峡水库蓄水加速了长江来沙的减少,近几年入海泥沙减少和河口口门区出现的冲刷有一半左右归因于三峡工程的运行;3)2000年以来,河口口门外水深超过7 m的大部分区域处于蚀退,尤以10～20m区域侵蚀最为强烈,但0m以上潮间带滩地较前一时段淤积加强,1994-2008年,四大滩地的面积平均增长了约34.2％.研究结果表明:入海泥沙减少是长江三角洲由淤积转为侵蚀的主要原因,三峡水库蓄水加剧了长江入海泥沙的减少及三角洲的侵蚀,河口滩地的逆势淤积是近年一系列的河口重大工程影响的结果. 相似文献
10.
气候变化对三峡水库运行风险的影响 总被引：2，自引：0，他引：2
未来气候变化对三峡工程建成后运行的影响研究对于三峡水库的合理调度以及华东、华中航运系统和电网调度等都具有重要的参考价值.以CGCM模拟试验结果为未来气候情景,通过蒙特卡罗试验,随机模拟了三峡地区在未来气候情景下月降水量分布的变化,探讨了三峡工程建成后运行期的气候风险并进行了定量评估.结果表明,在未来气候情景下,三峡水库运行期间,初夏和仲夏受洪涝影响的风险增大,隆冬和冬末由常年气候干旱造成的运行风险虽有减小,但由气候变率变化导致的极端干旱事件将使三峡水库的运行风险增加. 相似文献
11.
《地理学报(英文版)》2010,(5)
Based on the measured hydrological data from 1951 to 2008,the chain hydrological effect between Jingjiang River and Dongting Lake is analyzed by comparative method after the Three Gorges Project operation.The result indicates that 1) the scouring amount in Jingjiang River made up 78.9% of the total from Yichang to Chenglingji,and its average scouring intensity was higher than the latter;2) the water and sand diversion rates at the three outlets of the Jingjiang River were reduced by 2.33% and 2.78% separately;3) the proportion of multi-year average runoff and sediment through the three outlets in the total into the Dongting Lake decreased by 7.7% and 24.4% respectively;4) in Dongting Lake,the speed of sediment accumulation was lowered by 26.7%,in flood season,the runoff amount was 20.2% less than the multi-year average value,leading to seasonal scarcity of water year by year.The former prolonged the lake life,while the latter induced droughts in summer and fall in successive years,shortage of drinking and industrial water,shipping insecurity,as well as ecological problems such as decrease of birds and quick increase of Microtus fortis;5) The multi-year average values of sediment and flood transporting capacity at the lake outlet were respectively increased by 26.6% and 3.7%,the embankments were protected effectively.Then,to adapt to the new change of the river-lake relation,some suggestions were put forward,such as optimizing further operation program of the Three Gorges Reservoir,reexamining the idea of river and lake regulation,and maintaining connection of the river and the lake. 相似文献
12.
CHANG Jiang LI Jingbao LU Dianqing ZHU Xiang LU Chengzhi ZHOU Yueyun DENG Chuxiong 《地理学报》2010,20(5):771-786
Based on the measured hydrological data from 1951 to 2008, the chain hydrological effect between Jingjiang River and Dongting Lake is analyzed by comparative method after the Three Gorges Project operation. The result indicates that 1) the scouring amount in Jingjiang River made up 78.9% of the total from Yichang to Chenglingji, and its average scouring intensity was higher than the latter; 2) the water and sand diversion rates at the three outlets of the Jingjiang River were reduced by 2.33% and 2.78% separately; 3) the proportion of multi-year average runoff and sediment through the three outlets in the total into the Dongting Lake decreased by 7.7% and 24.4% respectively; 4) in Dongting Lake, the speed of sediment accumulation was lowered by 26.7%, in flood season, the runoff amount was 20.2% less than the multi-year average value, leading to seasonal scarcity of water year by year. The former prolonged the lake life, while the latter induced droughts in summer and fall in successive years, shortage of drinking and industrial water, shipping insecurity, as well as ecological problems such as decrease of birds and quick increase of Microtus fortis; 5) The multi-year average values of sediment and flood transporting capacity at the lake outlet were respectively increased by 26.6% and 3.7%, the embankments were protected effectively. Then, to adapt to the new change of the river-lake relation, some suggestions were put forward, such as optimizing further operation program of the Three Gorges Reservoir, reexamining the idea of river and lake regulation, and maintaining connection of the river and the lake. 相似文献
13.
The hydrological effect between Jingjiang River and Dongting Lake during the initial period of Three Gorges Project operation 总被引：2，自引：2，他引：0
Jiang Chang Jingbao Li Dianqing Lu Xiang Zhu Chengzhi Lu Yueyun Zhou Chuxiong Deng 《地理学报(英文版)》2010,20(5):771-786
Based on the measured hydrological data from 1951 to 2008, the chain hydrological effect between Jingjiang River and Dongting
Lake is analyzed by comparative method after the Three Gorges Project operation. The result indicates that 1) the scouring
amount in Jingjiang River made up 78.9% of the total from Yichang to Chenglingji, and its average scouring intensity was higher
than the latter; 2) the water and sand diversion rates at the three outlets of the Jingjiang River were reduced by 2.33% and
2.78% separately; 3) the proportion of multi-year average runoff and sediment through the three outlets in the total into
the Dongting Lake decreased by 7.7% and 24.4% respectively; 4) in Dongting Lake, the speed of sediment accumulation was lowered
by 26.7%, in flood season, the runoff amount was 20.2% less than the multi-year average value, leading to seasonal scarcity
of water year by year. The former prolonged the lake life, while the latter induced droughts in summer and fall in successive
years, shortage of drinking and industrial water, shipping insecurity, as well as ecological problems such as decrease of
birds and quick increase of Microtus fortis; 5) The multi-year average values of sediment and flood transporting capacity at the lake outlet were respectively increased
by 26.6% and 3.7%, the embankments were protected effectively. Then, to adapt to the new change of the river-lake relation,
some suggestions were put forward, such as optimizing further operation program of the Three Gorges Reservoir, reexamining
the idea of river and lake regulation, and maintaining connection of the river and the lake. 相似文献
14.
基于Copula函数的洞庭湖流域水沙丰枯遭遇频率分析 总被引：1，自引：0，他引：1
受人类活动的影响,水沙灾害事件相继发生,对人们的生产、生活造成了威胁。以洞庭湖流域代表性水文站的年径流量和年输沙量系列数据为基础,应用P-III型曲线分别拟合并求得“松滋口、太平口、藕池口”三口入湖、“湘江、资江、沅水、澧水”四水入湖和城陵矶站出湖年径流量、年输沙量的边缘分布函数,再采用水文事件遭遇分析中广泛应用的Copula函数,建立洞庭湖流域水沙联合分布模型,分析洞庭湖流域水沙丰枯遭遇频率。研究结果表明洞庭湖三口、四水和城陵矶站的水沙丰枯遭遇频率关系与洞庭湖流域的水沙运动有密切联系,运用该水沙耦合模型可以为洞庭湖流域防洪减灾提供重要的理论依据。 相似文献
15.
洞庭湖年径流泥沙的演变特征及其动因 总被引：18，自引：2，他引：16
通过对洞庭湖1951~1998年径流泥沙演变过程及其驱动力的全面分析表明, 径流泥沙关系密切, 其相关系数r = 0.9013。年径流量、年输沙量总体均呈同步减少趋势, 在演变过程中表现出明显的阶段性。由于湘、资、沅、澧四水流域产水量大, 森林覆盖率达52%以上, 连年兴建的水利工程及工农业、生活用水量的增加, 未能对四水河流水文特征产生根本性的影响, 其入湖径流泥沙基本处于稳定状态, 故没有对湖泊径流泥沙的演变造成深刻影响。而由长江中游河段的调弦口堵口, 下荆江系统裁弯和葛洲坝截流所引起的3次江湖水沙关系调整, 即是导致洞庭湖径流泥沙缓减速减的主动因子。 相似文献
16.
60年来洞庭湖区进出湖径流特征分析 总被引：2，自引：0，他引：2
采用集中度与集中期、M-K趋势检验法、变差系数法等方法对洞庭湖入湖径流河流（荆江三口、湖南四水）和出湖径流（城陵矶）年径流量序列进行分析。结果显示：① 洞庭湖区径流集中期为每年6~7月份,最大径流出现时间为6月底7月初;径流集中期合成向量方向介于103.2~190.2°之间,均能够反映各河流进出湖径流量最大值出现的月份。② 径流变差系数介于0.194~0.761之间,说明径流年际变率大。各河流径流极值比均在0.6以上,径流量衰减较为明显。③ 从径流的丰枯交替规律来看,湖南四水水量分配相对较为平均。荆江三口以藕池口丰水年和枯水年概率最大,分别占到32.79%和57.38%,径流年际变化较为剧烈,不利于水资源的合理利用。 相似文献
17.
利用1978特枯年、2000~2006年长江中下游宜昌、汉口、大通、城陵矶及湖口等水文实测资料,对2006年长江中下游出现特大枯水水情条件下的径流变化和江、湖与水库的调节过程进行分析。结果表明:长江中下游径流变化出现洪季不洪、枯季不枯特征,洪季来水量不到平常年的60%~70%,枯季基本维持平常年的来水量;其中长江上游来水量急剧减少是造成长江中下游洪季不洪的主要因素,三峡在枯水期间的调蓄对维持长江中下游干流的水量有一定的贡献,洞庭湖与鄱阳湖两大湖泊在枯季因干流水位显著降低形成的胁迫效应是长江中下游枯季不枯的重要因素。 相似文献
18.
The Dongting Lake is located in the south beach of the middle reaches of the Yangtze River. Its catchment, with an area of 262,823 km2 or about 12% of the total Yangtze River catchment, is situated between 28o43?29o32扤 and 112o54?113o8扙, and crosses Hubei and Hunan provinces in administrative division. The main tributaries include Xiangjiang, Zishui, Yuanjiang, Lishui rivers (4 Tributaries) and some local rivers, such as Miluo River, Xinqiang River and other little streams. In the nor… 相似文献
19.
The sediments of the Dongting Lake come from four channels (one of them was closed in 1959), connected with the Yangtze River, four tributaries (Lishui, Yuanjiang, Zishui and Xiangjiang) and local area, and some of them are transported into the Yangtze River in Chenglingji, which is located at the exit of the Dongting Lake, some of them deposit into drainage system in the lake region and the rest deposit into the lake. The annual mean sediment is 166,555x104 t, of which 80% come from the four channels, 18% from the four tributaries and 2% from local area, whereas 26% of the total sediments are transported into the Yangtze River and 74% deposited into the lake and the lake drainage system. Based on topographic maps of 1974, 1988 and 1998, and the spatial analysis method with geographic information system (GIS), changes in sediment deposition and erosion are studied in this paper. By overlay analysis of 1974 and 1988, 1988 and 1998, erosion and sediments deposition areas are defined. The main conclusions are: (1) sediment rate in the lake is larger than erosion rate from 1974 to 1998. The mean deposition in the lake is 0.43 m; (2) annual sediment deposition is the same between 1974-1988 and 1988-1998, but the annual volume of deposition and erosion of 1988-1998 is bigger than that in 1974-1988; (3) before the completion of the Three Gorges Reservoir, there will be 7.82x108 m3 of sediments deposited in the lake, which would make the lake silted up by 0.33 m; (4) in the lake, the deposition area is found in the north of the east Dongting Lake, the south-west of the south Dongting Lake, and the east of the west Dongting Lake; while the eroded area is in the south of the east Dongting Lake, the middle of the south Dongting Lake, the west of the west Dongting Lake, as well as Xiangjiang and Lishui river flood channels. 相似文献