【作者】 赵军凯；

【导师】 李九发；

【作者基本信息】 华东师范大学 ， 自然地理学， 2011， 博士

【摘要】 河湖关系的研究是当今社会和科学界普遍关注与研究的热点问题之一。科学地认识、正确地处理河湖关系,是维护健康河流、构建和谐人水关系以及人地关系的重点和关键。河湖水沙交换问题是河湖关系的核心问题,是河湖关系演变的纽带。河湖水沙变化和交换是河湖关系演变的驱动力之一。而河湖水交换则是水沙交换的核心和载体,水多则沙多,无水则无沙,因此,河湖水交换问题的研究是澄清河湖水沙交换问题乃至河湖关系的前提和基础。我国长江中下游的洞庭湖和鄱阳湖与长江干流河湖关系问题成为当前正确处理长江中下游人水关系乃至人地关系的焦点问题。自2005年4月首届长江论坛在武汉成功举办以来,《保护与发展长江宣言》得到社会各界的热烈响应,“维护健康长江、促进入水和谐”的新时期治江思路正在积极实践。毫无疑问,三峡工程建成后,在防洪、错峰等方面成效显著,尤其是2010年汛期三峡成功经历了接近1998年洪峰流量的考验、能有效控制长江上游的洪水,大量减少荆江、洞庭湖的洪水威胁。当前,需要改变治水理念,探索湖区人水和谐相处的可能途径,处理好长江中下游江湖关系,使长江中下游江湖水系肌体的调蓄功能得以充分发挥,维护健康长江、健康湖泊和健康河口。本论文运用普通水文学、工程水文学、随机水文学和水资源科学等的基本理论,采用多种时间序列统计分析方法、Mann-Kendall趋势和突变检验法、小波分析(Wavelet analysis)法,等定性与定量分析相结合,借助计算机技术,统计分析软件SPSS,科学计算软件Matlab等,利用ArcGIS、MapINFO和CoreIDRAWX3等地理信息系统软件和做图软件,在对长江中下游通江湖泊与干流水交换分析的基础上,得到洞庭湖和鄱阳湖与长江水交换的规律,推导出普适性的河湖水交换强度的量化公式,并在洞庭湖和鄱阳湖与长江干流水交换研究上取得成功,论文重点分析了三峡水库运行前后长江干流与两湖的水交换及其变化,并分析了特殊水文年份江湖水交换过程,以期探讨江湖水交换理论、以及合理开发利用水资源、并为维护长江中下游健康的江湖关系乃至健康的河口提供科学参考与建议。一、三峡水库对长江干流径流变化影响三峡水库运行以后,长江干流枯季径流年内所占比例增大,汛期末端月10月径流所占比例却减少,且宜昌站表现最突出。说明三峡水库运行后长江干流径流特征发生了变化,三峡水库运行加剧了长江中下游汛期径流减少的趋势,加大了枯季径流增加的趋势；并且,2002年干流径流序列存在跳跃点与2003年三峡水库蓄水有关。可见,三峡水库运行改变了坝下游径流的年内分配,使年内分配差值减小。二、三峡水库运行前后江湖水交换规律1洞庭湖与长江干流水交换。三峡水库运行之后2003-2009年与1998-2002年相比三口分流量之和减小了220×10~8m~3。2003-2009年9-10月份三口流量之和比蓄水前减少了870m~3/s,减少幅度为38.9%。2003-2009年宜昌站流量50000m~3/s和30000m~3/s时,三口分流比较1998-2002年略增；10000m~3/s时,三口分流比较1998-2002年减少。2003-2009年与以前时段相比,城陵矶(七)站出湖流量在宜昌站高流量时受干流顶托作用更明显,在中、低流量时,与2000-2002年相比城陵矶流量变化不大。2鄱阳湖与长江干流水交换规律。湖口站多年平均径流量在三峡水库运行前后变化不明显。可是径流的年内分配在2000s与以前相比枯季所占比例增加,水库蓄水月9和10月份径流年内分配比例较1990s有所增加。2010年9月和10月湖口径流量增加,是由于长江干流流量小、水位低,对湖口顶托作用减少而引起的。2010年鄱阳湖与长江干流水交换系数I_p=0.21,且该年长江干流没有发生江水倒灌现象,长江对鄱阳湖顶托作用小,同样说明了这一点。长江水倒灌鄱阳湖现象,年代际间倒灌规律发生了变化,2000s与同样枯水年组1980s和1960s相比,江水倒灌年数、总天数和总水量都减少。三、不同径流频率条件下江湖水交换计算成果1利用水量平衡原理计算了不同频率组合下长江干流与洞庭湖水交换量。当长江干流径流频率为5%的丰水年,恰遇四水也是5%的丰水年时,则洞庭湖可以分洪658×10~8m~3,同年补给长江干流水量为3191×10~8m~3；三口和四水都是50%的平水年时,洞庭湖分长江干流水量为545×10~8m~3,同年补给长江干流2403×10~8m~3水量；当三口和四水都是95%的特大干旱年时,洞庭湖只能补给长江1873×10~8m~3的水量。2利用水量平衡原理计算了不同条件下长江干流与鄱阳湖水交换量。频率为5%、50%、75%和95%时,湖口年径流量分别为2300×10~8m~3、1440×10~8m~3、1175×10~8m~3和930×10~8m~3。四、特殊水文年份江湖水交换过程1典型枯水年江湖水交换(1)1978年洞庭湖和鄱阳湖与长江干流水交换系数分别为0.57和0.56,洞庭湖和鄱阳湖与长江水交换作用处于稳定状态,该年发生了长江水倒灌入鄱阳湖的现象。2006年洞庭湖和鄱阳湖与长江干流水交换系数分别为0.89和0.51,前者是湖对长江强补给状态,后者是江湖作用接近稳定状态。(2)2006年三峡水库运行使长江中下游干流径流全年分配趋于均匀。特别是增大了枯季径流量,使河槽水位上升,影响了江湖水交换的过程,使长江下游出现枯季不枯的好现象。(3)1978年和2006年都是长江流域典型枯水年,中游通江湖泊对干流补水作用更明显,尤其是2006年鄱阳湖干流补给水量为1564×10~8m~3,超过了平水年。2典型丰水年江湖水交换(1)1954年洞庭湖和鄱阳湖与长江干流水交换系数分别为0.35和0.34,洞庭湖和鄱阳湖与干流水交换作用较强,发挥了湖泊的分洪调蓄作用。1998年洞庭湖和鄱阳湖与长江水交换系数分别为0.46和0.39,洞庭湖与干流水交换强度接近多年平均水平,主要作用是分洪,但没有1954年分洪作用大；鄱阳湖对长江的分洪作用较强,但也没有1954年分洪作用大。(2)洞庭湖和鄱阳湖1954年补给长江水量为分别为5248x10~8m~3和2481×10~8m~3,分别约占同期大通径流量的38.6%和19.0%；1998年补给长江水量分别为3994x10~8m~3和2650×10~8m~3,分别约占同期大通径流量的32.1%和21.3%。3无论丰水年还是枯水年洞庭湖和鄱阳湖对长江的调蓄作用都是非常重要的。丰水年,两湖对长江干流起到分洪、消峰等作用,减轻下游洪水压力；枯水年,两湖对长江干流主要是水量补充作用,使得下游河道保持一定的流量。五、江湖水交换量化研究成果用河湖水交换系数来表示河湖水交换强度,并推导出了普适性的河湖水交换系数的量化计算公式((?)),在洞庭湖、鄱阳湖与长江干流水交换研究中推导出其江湖水交换系数计算公式((?)和((?)),并取得成功。两湖与长江干流水交换量化研究结果表明,历年的江湖水交换系数能够反映两湖与长江干流水交换的真实情况。此公式具有应用价值。更多还原

【Abstract】 At present, the research on the river-lake relation is one of the popular topics which attracted various attentions from researchers and the whole society. Scientific understanding and proper management on the river-lake relation is the key to keep river healthy, as well as to build a harmonious human-water and human-land relationship. Water and sediment exchanges of river-lake system are the core issues of the relation of river-lake system, which are the bond of the evolution of the relation of river-lake system. Variations in the water and sediment and exchanges of them in the river-lake system are one of the driving forces in the evolution of the relation of river-lake system. Moreover, water exchange in the river-lake system is the carrier of the sediment exchange between rivers and lakes, which means more water more sediment and no water no sediment. Consequently, the study of water exchange in the river-lake system is the premise and basis for clarifying the problem of water and sediment exchange between river and lake, or even the relation of river-lake system.The relation of river-lake system in the Dongting Lake and the Poyang Lake at the middle and lower reaches of the Yangtze River has become the focus to properly handling the man-water relationship or even the man-land relationship of the Yangtze River. Since the First Yangtze River Forum Annual Meeting was held successfully in Wuhan City in April 2005, Protection and development declaration for Yangtze River received enthusiastic response from the whole society. At present, the ideas of ’Maintain a healthy Yangtze River, Promote harmonious man-water relationship’are being actively practised. Beyond all doubt, after the completion of the Three Gorges Project (TGD), it received remarkable achievements in controlling floods, avoiding peak discharge et al. Especially, in the flood period of 2010, when the peak flow was close to that of 1998, it effectively controlled the upper Yangtze River flooding, reduced the amount of flood in the Jingjiang reach and the Dongting lake, and mitigated the flood disaster of the Jingjiang reach. It is necessary to change the contemporary ideas on water management, and to explore a reasonable way to reach a harmonious man-water relationship in lake area, so that the potentialities of lake regulation of river-lake system can be brought into full function. Simultaneously, it is in favor of maintenance of a healthy Yangtze River arid Estuary. Basic theories of general hydrology, engineering hydrology, stochastic hydrology and water resources sicence, as well as various methods of time-series statistical analysis, Mann-Kendall tendency and mutation inspection, Wavelet Analysis etc., were applied in this paper. By using qualitative and quantitative analysis, and with the aid of computer technology, statistical analysis software SPSS 15.0, scientific calculation software Matlab R2007b, geographical information system software ArcGIS and MapINFO, drawing software CorelDRAW X3 etc., this paper, based on the analysis of water exchange between mainstream and lakes, received the rules of water exchange between the Dongting Lake and the Yangtze River as well as between the Poyang Lake and the Yangtze River, deduced a quantitative formula of river-lake water exchange intensity which has been successfully used in the research on the water exchange of the Dongting Lake and the Poyang Lake. In this paper, the author emphatically analyzed the variations in the water exchange between two lakes and the mainstream of the Yangtze River before and after the operation of the Three Gorges Reservoir (TGR) and exchange processes in special hydrologic years. The purposes are to probe the theory of the water exchange of river-lake system, to provide scientific basis and some suggestions for rational utilization of water resources, and for maintenance of a healthy relationship of river-lake system as well as a healthy estuary.ⅠThe impact of the TGR on the variations in the runoff of the Yangtze RiverSince the operation of the TGR, the proportion of the runoff of the mainstream of the Yangtze River in the dry season in that of a whole year has risen. In the meantime, the proportion of runoff in October, which is the last month of the flood season, has gradually decreased. This phenomenon was particularly prominent at Yichang station. In conclusion, the runoff of the Yangtze River has changed after the completion of the TGD. The results from these analyses on the impact of the TGR on the mainstream runoff indicate that the operation of the TGR intensified the trend of the decrease in the flood season runoff in the middle and lower reaches of the Yangtze River and enhanced the tendency of the increase in the dry season runoff. Furthermore, the jumping point of the mainstream runoff sequence in 2002 was related to the impounding of the TGR in 2003. Therefore, the operation of the TGR has changed the distribution of the runoff within a year downstream of the dam, which made the proportion of each month’s runoff within a year equably.ⅡThe rules of river-lake water exchange before and after the operation of TGR i) The rules of water exchange between the Dongting Lake and the mainstream of the Yangtze River. After the operation of the TGR, the total runoff of Three Inlets during 2003-2009 decreased by 220×10~8m~3, compared with 1998-2002. The total mean flowin September and October of Three Inlets decreased by 870m~3/s during 2003-2009. The rate of decrease was 38.9%. During 2003-2009, when the flow at Yichang was 50000 m~3/s and 30000 m~3/s, the split ratio of Three Inlets increased, but when the flow at Yichang reduced to 10000 m~3/s, the split ratio of Three Inlets decreased, compared with that during 1998-2002. After the operation of the TGR, 2003-2009, compared to the previous data, the outflow of Chenglingji (Qilishan) was more affected by the waterback effect of trunk stream of the Yangtze River when the flow at Yichang was biger, while the outflow of Chenglingji (Qilishan) changed little when the flow at Yichang was medium or low, compared with that of 2000-2002.ii) The rules of water exchange between the Poyang Lake and the mainstream of the Yangtze River. After the completion of the Three Gorges Project (TGP), the annually mean discharge changed little, but proportion of the runoff in the dry season in the annual runoff of the mainstream of the Yangtze River in 2000 increased, compared with previous data. In September and October, this was also the reservoir impounding water time, the proportion of the runoff of this period within a year increased, compared with 1990s. The increase in the runoff at Hukou during September and October in 2010 was was caused by the lower water level, lower flow and weak backwater effect of the Yangtze River. The coefficient of water exchange I_p equals 0.21, without backward water from the mainstream of the Yangtze River to the Poyang Lake in this year, which also shows this point.The phenomenon of backward flow from the Yangtze River to the Poyang Lake at Hukou changed from decade to decade. The number of years and days when there was backward water declined in 2000s when compared with that during 1960s and 1980s, and the water volume of backward water also decreased simultaneously.ⅢResults of river-lake water exchange with the runoff of different frequenciesⅰ) Under the conditions with runoff of different frequencies, the water exchange between the mainstream of the Yangtze River and the Dongting Lake was computed with the water balance principle. The Four Tributaries experience 5% high flow year when the mainstream of the Yangtze River is in 5% rich water year.The water volume of flood diversion to the Dongting Lake from the mainstream is 658×10 m and the lake supplies3191×10~8m~3 of water for the Yangtze River at the same year. When Three Inlets and Four Tributaries experience 50% normal year, the water volume of flood diversion to the Dongting Lake is 545×10~8m~3 with supplying 2403×10~8m~3 of water for the mainstream, Whereas when the Three Inlets and Four Tributaries are in 95% low flow year, the Dongting Lake only supplies 1873×10~8m~3 of water for the Yangtze River.ii) Under the conditions with runoff of different frequencies, the water exchange between the mainstream of the Yangtze River and the Poyang Lake was computed by using the water balance principle. The annual runoff of Hukou is 2300×10~8m~3、1440×10~8m~3、1175×10~8m~3 and 930×10~8m~3 when the frequencies are 5%、50%、75% and 95%.IV River-lake water exchange process in special hydrological yearsi) Main conclusions on water exchange between river and lakes in the typical low flow years(1) The water exchange coefficient was 0.57 between the Yangtze River and the Dongting Lake and 0.56 between the Yangtze and the Poyang in 1978. Water exchange was stable between the mainstream of the Yangtze River and the Dongting and the Poyang Lake. The backward flow from the river to the lake appeared in this year. In 2006, the water exchange coefficients of these two systems were 0.89 and 0.51 respectively, the former showed that there was strong water supply from the lake to the river, while the latter revealed a situation of approximately stable water exchange between the river and the lake.(2)The annual runoff distribution of the middle and lower reaches of the Yangtze River became more uniform after the operation of TGR in 2006. The runoff increased, especially in dry season, which led to the water level rise in the channel, affecting the water exchange process between the river and lakes, which resulted in rich water in the Yangtze River in the dry season, compared to other low flow years.(3) 1978 and 2006 were both typical lower flow years of the Yangtze River basin, the water supply, therefore, from river-connected lakes in the middle reach to the mainstream was more obvious, especially in 2006. For instance the Poyang Lake supplied 1564×10~8m~3 of water for the river, which was much more than the normal year.ii) Main conclusions on water exchange between river and lakes in typical flood years (1) Water exchange coefficient of Dongting-Yangtze was 0.35 in 1954, and 0.34 for Poyang-Yangtze. Water exchange was strong between the both two lakes and the river, and they played the main role in flood diversion, runoff regulation and storage. The two coefficients in 1998 were 0.46 and 0.39 respectively. The strength of the Dongting-Yangtze water exchange was close to the normal year, whereas the main function, flood diversion, was much weeker than that in 1954. The situation was similar in the Poyang lake, despite that the flood diversion was relatively stronger.(2) The volume of the water supply from the Dongting and the Poyang Lake to the Yangtze River was 5248×10~8m~3 and 2481×10~8m~3 in 1954, which accounted for nearly 38.6% and 19.0% of the runoff at Datong Station during the same period. For the year of 1998, the volume of the water supply was 3994×10~8m~3 and 2650×10~8m~3, which accounted for 32.1% and 21.3% of the runoff at Datong.ⅲ) The Dongting and the Poyang Lake played an important role in water regulation and storage for the Yangtze River either in high or low flow years. In flood years, the two lakes store water and smooth the peak flow of the flood, reducing the downstream flooding threatening.In low flow years, the two lakes play a prominent role in water supply and maintaining a certain flow downstream.Ⅴ. Achievements on quantified analysis of water exchange between the river and the lakeWater exchange coefficients of the Yangtze-Dongting and the Yangtze-Poyang were able to indicate the real water exchange between the two lakes and Yangtze over the years. Therefore, it is a practical way for common use to quantitatively analyze the river-lake water exchange.更多还原