松花江干流冰期河道内生态需水研究

发布时间：2018-09-01 11:35

【摘要】：在气候变化和人类活动的双重影响下,我国水生态环境受到严重破坏。极端天气频发,河道流量不断减小,河道水质不断恶化,2013我国劣V类水河长比例14.9%,比2012年上升0.6个百分点。在当前变化环境下,水生态问题越演越烈,特别是北方河流高达5个月的冰封期,对河道生态系统产生了深远影响。自1980年至2000年,松花江流域内由于降雨较少、水资源过度利用和不合理开发,流域内有2条河流发生过断流,分别为呼兰河和蚂蚁河,最大断流长度为50km、65km,占各自河流总长度的0.6%、2.9%,断流累计天数为78天和23天。河流断流及水质污染对河道内的生态环境及其生物多样性均有较大的负面影响,在此背景下,水生态逐渐成为我国治水实践与科学研究的热点和重难点。我国从上世纪80年代开始针对生态需水开展系统性的研究,但结合水生生物栖息地来评估河流生态需水量的应用仍处在探索阶段,特别是北方寒区冰期易出现“连底冻”现象,对水生生物的生存及河道的生态系统带来严重影响,使得现有的方法对北方寒区冰期生态需水的计算均存在很大的局限性。因此研究我国北方寒区冰期河道内生态需水,对于河流生态修复及管理具有重要意义。本文以松花江干流哈尔滨至佳木斯为研究区域,基于冰封期河道特性和物理栖息地模型,从维持河道内代表性物种越冬期生存的角度,对河道内生态流量进行预测分析。主要结论如下:(1)对1962-2010年松花江干流冰期水文要素进行分析发现:松花江干流哈尔滨、依兰和佳木斯断面的多年平均流量均呈现减小趋势,倾向率分别为-1.816m3/s、-0.2419m3/s、-3.539m3/s;流速同样呈现减小趋势,但减小趋势不明显;冰盖厚度的倾向率分别为-0.0329m、-0.0311m、-0.0325m。利用多元非线性回归模型可以较好的拟合出冰盖厚度随积温、流量和流速的变化趋势,且模型在纳什系数的检验下取得较好的相关性。(2)确定松花江干流不同鱼类主要越冬场分布。以PHABSIM模型为基础,分别以温水性的雅罗鱼和冷水性鳌花鱼为代表性物种,对不同流量条件下两种鱼类越冬期有效期栖息地面积进行模拟,确定松花江干流哈尔滨至佳木斯河段鳌花鱼和雅罗鱼越冬期的栖息地主要分布在距哈尔滨段面下游50-70km、270-280km和390-400km。(3)结合主要研究河段代表性物种越冬场位置,分别模拟不同流量下鳌花和雅罗鱼越冬期栖息地加权可利用栖息地面积变化,依据相关参数,得出WUA-流量变化关系曲线,确定生态流量范围。同时结合哈尔滨、依兰和佳木斯站1962-2010年11月至次年3月份多年月平均径流资料分析,考虑越冬场径流量的实际情况,将鳌花鱼越冬期的最小生态流量定为300m3/s,雅罗鱼越冬期的最小生态流量定为200m3/s。
[Abstract]:Under the dual influence of climate change and human activities, China's water ecological environment has been seriously damaged. With frequent extreme weather, the river flow is decreasing, and the water quality of the river is deteriorating. In 2013, the proportion of bad V river length in China is 14.9%, which is 0.6 percentage point higher than that in 2012. In the present changing environment, the problem of water ecology is becoming more and more serious, especially the frozen period of up to 5 months in the northern rivers, which has a profound influence on the river ecosystem. From 1980 to 2000, due to less rainfall, excessive utilization and unreasonable exploitation of water resources, two rivers in the Songhua River basin, namely Hulan River and Ant River, were cut off. The maximum cut-off length is 50 km / m ~ (65) km, which accounts for 0.6 ~ 2.9% of the total length of the respective rivers, and the total number of days of disconnection is 78 days and 23 days respectively. The river disconnection and water pollution have a great negative effect on the ecological environment and biodiversity in the river. Under this background, the water ecology has gradually become a hot and difficult point in the practice and scientific research of water control in China. Since 1980s, China has carried out systematic research on ecological water demand, but the application of evaluating river ecological water demand in combination with aquatic habitat is still in the exploratory stage, especially in the cold regions of northern China, which is prone to the phenomenon of "continuous bottom freezing". It has a serious impact on the survival of aquatic organisms and the ecosystem of river channels, which makes the existing methods have great limitations on the calculation of ecological water demand in the cold regions of northern China during the glacial period. Therefore, it is of great significance to study the ecological water demand in the glacial river course in the cold region of northern China for river ecological restoration and management. Taking Harbin to Jiamusi as the main stream of Songhua River as the study area, based on the characteristics of the frozen river and the physical habitat model, the ecological discharge in the river is predicted and analyzed from the point of maintaining the survival of the representative species in the river during the wintering period. The main conclusions are as follows: (1) based on the analysis of the hydrological elements of the Songhua River during the glacial period from 1962 to 2010, it is found that the annual average discharge of the Songhua River mainstream in Harbin, Yilan and Jiamusi sections shows a decreasing trend. The tendency rate of the ice sheet thickness is -0.0329mt / m ~ (-1) -0.0311mN ~ (-1) -0.0311mU ~ (-0.0325m), the tendency of the velocity is also decreasing, but the decreasing trend is not obvious, and the tendency rate is -1.816m3 / s ~ (-1) -0.2419m3 / s ~ (-1) -3.539m3 / s, respectively. By using multivariate nonlinear regression model, the variation trend of ice sheet thickness with accumulated temperature, flow rate and velocity can be well fitted. The model has good correlation under the test of Nash coefficient. (2) the distribution of main overwintering field of different fishes in the main stream of Songhua River is determined. Based on the PHABSIM model, the habitat area of the two species in overwintering period was simulated under different flux conditions, respectively, using the warm water Arrowhead and the cold-water chrysanthemum as the representative species. It is determined that the habitat of Acanthophora and Artemisia in the period of overwintering from Harbin to Jiamusi reaches of Songhua River is mainly distributed in 270-280 km and 390-400 km from the lower reaches of Harbin section. (3) the location of overwintering field of representative species in this section is studied. The changes of habitat area in overwintering period were simulated under different flow conditions. According to the relevant parameters, the relationship curve of WUA- flux was obtained, and the range of ecological flow was determined. At the same time, combining with the average monthly runoff data of Harbin, Yilan and Jiamusi stations from Nov.1962-2010 to March of next year, considering the actual situation of wintering runoff, The minimum ecological flow in overwintering period was determined as 300m3 / s, and the minimum ecological flow in overwintering period of Arrowhead was 200m3 / s.
【学位授予单位】：东华大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X143

【相似文献】