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南四湖地处鲁南泰沂山前冲积平原与鲁西南黄泛平原的交界地带,是中国北方地区最大的淡水湖,也是中国第6大淡水湖。南四湖流域多年平均降水量691mm,人均水资源量不足300m^3,时空分布严重不均,属严重缺水地区。回顾了国内外生态需水量研究进展,对南四湖生态调查资料进行了分析,提出了南四湖生态需水量计算的方法,计算了南四湖最小生态需水量和相应的南四湖最小生态水位。 相似文献
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基于水盐平衡的南通地区河流系统生态需水量研究 总被引:1,自引:1,他引:0
论述了水盐平衡的概念,从水盐平衡的基本原理出发,探讨了南方地区维持河流水盐平衡的生态需水量计算方法,以此生态需水校核河道整治的断面是否达到水盐平衡的要求。以南通地区的河流系统为例,估算其多年平均维持河流水盐平衡的生态需水量,并据此对河道整治提出了要求。 相似文献
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基于RVA法的河流生态需水量研究 总被引:1,自引:0,他引:1
以河流生态水文变化的指标体系(Indicator of Hydrologic Alteration,IHA)为基础,立足整体河流水文情势的流量谱系,采用变异性范围法(Range of Variability Approach,RVA),进行基于长系列历史流量资料的河流生态需水量估算,并以山西省5条较大河流的生态敏感断面为对象进行研究。结果表明,利用本方法估算的结果是合理的,可为河流生态需水量的估算和水资源的可持续开发利用提供科学依据。 相似文献
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介绍了生态水力半径法的计算过程,并以淮河的二级支流贾鲁河为例计算了中牟和扶沟两个水文站不同水文频率年对应的最小生态需水量。根据研究区域的气候、地理特征和流域范围内鱼类对流速的要求对Tennant法的计算标准进行修正,并使用修正后的Tennant法对中牟和扶沟水文站最小生态需水量的计算结果进行验证。结果表明,生态水力半径法得到的中牟站丰、平、枯水年和扶沟站丰、平水年最小生态需水量计算结果是合理的,扶沟站枯水年最小生态需水量多数月份无法满足Tennant法设定的最小值,可用Tennant法计算结果代替。该方法更多地考虑了河流水文水力学特征和河流生态系统中水生生物对栖息地的要求,具有更强的生态学意义。 相似文献
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生态水力半径法计算河道内生态需水量研究 总被引:3,自引:1,他引:3
生态需水的研究已成为国内外地球科学领域普遍关注的一个热点问题.在理论研究的基础上,根据雅砻江干流独特的生态环境与环境保护目标,采用包括水文和生物两方面信息的生态水力半径法,计算了雅砻江干流温波、甘孜、雅江3站各年河道内生态需水量,其结果基本上处于Tennant法所设定的最小和适宜生态需水量之间;设定的计算标准主要考虑当地水生生物生活习性及气候特点,符合当地河流生态与环境条件,因此应用生态水力半径法来计算河道内生态需水量是可行的. 相似文献
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生态需水量分为河道内和河道外两部分。根据北方山区的特点,以承德市滦河流域为例,采用合理的计算方法,对承德市滦河流域生态需水量进行了估算。最后,对计算结果进行了分析和评价,并对如何保证生态需水量提出建议。 相似文献
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Tennant法计算南沙河河道生态需水量 总被引:2,自引:0,他引:2
随着人口的快速增长和经济社会的调整发展,生态系统尤其是水生态系统承受越来越大的压力,出现了水源枯竭、水体污染和富营养化等问题。通过对河流生态需水量的计算,有效地保障南沙河城区段景现及生态系统需水要求。利用Tennant法计算南沙河城区段生态需水量。 相似文献
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河道生态环境需水量的计算方法众多,不同方法的适用性也不同;且根据不同生态环境的要求,生态需水量也有较大差别。本文采用Tennant法和水量平衡法进行阜阳城区河道的生态需水量分析,并按照最基本的生态要求和生态效果非常好的两种工况进行研究,确定在不同生态效果条件下的河道生态需水量。 相似文献
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东平湖老湖区生态环境需水量研究 总被引:3,自引:2,他引:1
东平湖既是防御黄河下游大洪水的重要分滞洪区,又是南水北调东线最末一级调度湖泊,具有防洪、调水、航运、旅游、养殖、引水灌溉等多项功能,其中老湖区是其发挥各项功能的基础。基于东平湖的功能,分别计算其本底需水量、蒸散发需水量、渗漏需水量、水生生物栖息地需水量、景观娱乐需水量、稀释净化需水量、航运需水量,并综合考虑湖泊内生态和环境影响因子,建立生态环境需水量优化计算模型,对东平湖老湖区生态环境需水量进行了计算。结果表明:东平湖老湖区的适宜生态环境需水量为2.75亿m3,对应的适宜水位为41.20 m。 相似文献
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《Journal of Great Lakes research》1986,12(2):109-116
An analysis was conducted of the Lake Erie water balance for 1940–79, based upon the individual hydrologic components, including thermal expansion and consumptive use. Particular emphasis was given to the continuity of the system. Annual and monthly statistics are presented for each of the water balance components. While the Detroit River contributed 87 percent of the Lake Erie total water supply, the variability of the net basin supplies was also found to be of importance in explaining annual water level fluctuations. A major step function was found to occur in the annual water balance between 1958 and 1959, which illustrates the large discontinuities that can occur when calculating the net basin supplies from residuals rather than directly from precipitation, runoff, and evaporation. The annual water balance for 1959–79 was found to be well satisfied with an average annual residual of about 0.5 percent of the Detroit River or Niagara River flow. A distinct seasonality was noted in the mass continuity of the monthly water balance. Also on a seasonal basis, the change in storage due to thermal expansion was significant during the late spring and early fall months. 相似文献
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Jagjit Kaur Gopi Jaligama Joseph F. Atkinson Joseph V. DePinto Adrienne D. Nemura 《Journal of Great Lakes research》2007,33(1):62-82
A two-dimensional numerical model was developed to study dissolved oxygen (DO) kinetics in a dredged Lake Erie tributary. The model design was aimed to specifically address the fact that many tributaries to the Great Lakes are dredged periodically for navigation, and that resultant changes in morphology and hydraulics can have significant impacts on DO. Due to the greater depths caused by dredging, river velocities slow considerably and vertical mixing is not as effective, leading to thermal stratification and potential short-circuiting of warmer upstream flow. The model solves the two-dimensional (laterally averaged) hydrodynamic and mass balance equations to simulate transport and transformation relevant to dissolved oxygen using an alternating direction, implicit finite difference method. Effects of oxygen-demanding pollutants from municipal and industrial discharges and also from nonpoint sources are included. A model application was developed for the Black River (Ohio), a tributary of Lake Erie. The river is dredged periodically, becomes stratified during the low flow summer months, and is affected by changing lake levels associated with seiching in Lake Erie. After calibration and confirmation, the model was used as a diagnostic tool to understand the impact of various loading sources on low DO levels observed along the bottom of the river. It is shown that sediment oxygen demand (SOD), combined with the river hydraulics, is the primary cause for low DO levels in the Black River. 相似文献
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滇池流域水资源供需平衡初步分析 总被引:2,自引:0,他引:2
昆明市是云南省政治、经济、文化中心,全国历史文化名城;是面向东南亚的国际商贸旅游城市和国际大通道.近年来,随着人口增加,社会经济的发展,需水量猛增,加之水资源缺乏和水质污染严重,从而导致水资源危机.目前,昆明市己被列入全国100个严重缺水的城市之一,成为我国因缺水和水环境恶化而陷入困境的城市.文章从分析滇池可供使用的实际水资源总量入手,提出了滇池流域可供使用洁净水资源的概念,并对昆明市城市生活及工业需水进行供需平衡分析,观点较以往有所突破,概念清晰,其结论对研究昆明市今后不同条件下的水量余缺情况具有一定的参考价值. 相似文献
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博斯腾湖沼泽芦苇需水规律研究 总被引:2,自引:0,他引:2
通过试验对博斯腾湖沼泽芦苇的7~9月的需水规律进行了研究。结果表明博斯腾湖芦苇7~9月的蒸散量为281.8mm、261.7mm和156.6mm,芦苇的蒸散强度和参考作物潜在蒸发蒸腾量以及水面蒸发强度都有着较好的相关关系;7月、8月、9月的植物修正系数分别为:1.50,1.43,1.06,7~9月平均值为1.33;并根据Penman-Monteith公式算出7月、8月、9月月植物系数,分别为:1.60,1.61,1.46,7~9月的平均值为1.56。 相似文献
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Three separate procedures were used to estimate the sediment oxygen demand (SOD) in the central basin of Lake Erie and were compared with other estimates determined previously and with historical data. First, whole core incubations involved sealing sediment cores at 12°C to ensure no interaction between the overlying water and the atmosphere and monitoring continuously to define the linear disappearance of oxygen. Second, sediment plugs were placed inside flow-through reactors and the influent and effluent concentrations were monitored to obtain steady-state reaction rates. Third, an extensive data set for the central basin of Lake Erie was compiled for input into the diagenetic BRNS model, and the SOD was calculated assuming all primary redox reactions, but no secondary reactions. All three procedures produced estimates of SOD that were in reasonable agreement with each other. Whole core incubations yield an average SOD of 7.40 × 10−12 moles/cm2/sec, the flow-through experiments had an average SOD of 4.04 × 10−12 moles/cm2/sec, and the BRNS model predicts an SOD of 7.87 × 10−12 moles/cm2/sec over the top 10 cm of sediment and appears to be calibrated reasonably well to the conditions of the central basin of Lake Erie. These values compare reasonably well with the 8.29 × 10−12 moles/cm2/sec obtained from diffusion modeling of oxygen profiles (Matisoff and Neeson 2005). In contrast, values reported from the 1960s to 1980s ranged from 10.5–32.1 × 10−12 moles/cm2/sec suggesting that the SOD of the central basin has decreased over the last 35 years, presumably, in response to the decrease in phosphorus loadings to Lake Erie. However, since hypoxia in the hypolimnion persists these results suggest that improvement in hypolimnetic oxygen concentrations may lag decreases in loadings or that the hypolimnion in the central basin of Lake Erie is simply too thin to avoid summer hypoxia during most years. 相似文献
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《Journal of Great Lakes research》1987,13(4):738-756
In situ measurements of water column oxygen consumption and sediment oxygen demand (SOD) in the central basin of Lake Erie are historically 50% to 100% larger than observed from decreases in stocks of dissolved oxygen. Recent statistical and modeling analyses of observed oxygen data, and in situ measurements of SOD using a dome with gentle mixing, suggest consistent values for SOD of 0.2 to 0.3 g/m2/d. These values are lower than historical estimates. Three SOD models applicable to Lake Erie are examined. One (Walker) describes SOD as a function of oxygen concentration, and of biological and chemical components. The second (Klapwijk) describes SOD as a function of carbonaceous oxidation, nitrification, denitrification, and ammonia produced by diffusion and in the aerobic, anoxic, and anaerobic zones of the sediments. The third (DiToro) describes SOD as a function of settling fluxes of algae and organics from the water column, and assumes that all anaerobically produced carbon is oxidized in the sediments. It is suggested that aspects of the latter two models are required for future modeling of SOD in Lake Erie. More measurements of sediment profiles of POC are required to resolve certain modeling questions. 相似文献