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91.
随着水质监测连续化的需求增加,河流水质在线监测站布设成为不可忽视的问题。本文采用水文模拟模型HSPF对台湾淡水河流域进行水量水质联合模拟。水文模拟以9个测站比对,纳什效率系数多数大于0.7;相关系数r皆大于0.7。水质模拟以27个测站比对,生化需氧量、氨氮、悬浮固体、溶氧的修正平均百分误差多数小于25%。基于水质变化率和水质超标率提出水质敏感河段概念,并以此确定为补充布设水质在线监测站点的优先河段。研究指出,淡水河流域水质在线监测站目前仍缺乏且位置不尽合理,应优先补充三峡河的三峡大桥、景美溪的宝桥、基隆河的江北桥水质在线监测站。 相似文献
92.
长大隧洞工程建设中地下水处理的实践及思考 总被引:1,自引:0,他引:1
以引汉济渭工程秦岭输水隧洞(越岭段81.779 km)为例,围绕该隧洞建设过程中的地下水问题,介绍其总体富水情况以及地下水预测方法。通过对秦岭各支洞抽排水措施的综合研究,给出了抽排水方案的设计步骤,结合不同涌水的处理提出了突涌水的处理思路,并介绍了目前国内先进的突涌水预测手段及应用效果。根据秦岭隧洞抽排设备的配置思路以及洞外环保处理情况,指出了目前地下水处理过程中存在的问题并提出相应的解决方法。通过引汉济渭工程建设过程中地下水处理情况的介绍、探讨和分析,对长大隧洞处理类似地下水问题提供一定的借鉴。 相似文献
93.
引汉济渭工程运行调度模式研究 总被引:1,自引:0,他引:1
从引汉济渭工程运行调度的实际需求出发,设计了工程运行调度新模式并集成实现。基于Hadoop搭建工程运行调度大数据服务平台,基于数字地球构建了工程运行调度可视化仿真系统,基于云服务架构建立工程运行调度应用支撑平台,以主题、组件、知识图为牵引建立了工程运行调度应用支撑库,基于数字地球和应用支撑平台构建了工程调配水一体化数字水网,基于平台、数字水网、组件、知识图搭建了工程运行调度主题业务应用,实现了运行调度业务主题化云服务。该模式技术理念先进,应用灵活方便,适用性强,可为工程运行调度提供重要技术支撑,具有良好的应用前景。 相似文献
94.
针对引汉济渭工程运行调度的实际需求和特点,基于云计算技术,采用面向服务的体系结构(SOA)和JAVA EE平台技术架构,研发了基于云服务架构的引汉济渭工程运行调度综合服务平台,建立了基于平台、组件、知识图及可视化工具灵活搭建的引汉济渭工程运行调度业务应用系统构建模式,形成基于平台、基于组件、基于主题、基于可视化的应用模式,解决了传统的工程运行调度系统应用性差、功能单一、可扩展性差及应用模式单一等问题。通过平台提供工程运行调度业务服务,为工程联合调度提供技术支撑。 相似文献
95.
陕北无定河流域土壤侵蚀与植被覆盖和降雨关系研究 总被引:1,自引:0,他引:1
基于2000—2014年陕北无定河流域日降水、DEM、土壤类型、MODIS NDVI等数据,利用修正通用土壤流失方程(RUSLE)估算了流域土壤侵蚀情况,定量分析了植被覆盖和降雨在土壤侵蚀中的作用,结果表明:(1)无定河流域土壤侵蚀以微度侵蚀为主,平均占流域面积的88.35%,各土壤侵蚀等级面积比例随等级的升高而降低。2000—2014年微度侵蚀面积比例为下降趋势,轻度及以上等级面积比例均为上升趋势。(2)不考虑降雨因子影响时,无定河流域仍以微度侵蚀为主,且为增加趋势,而其他土壤侵蚀等级均为下降趋势。不考虑植被覆盖因子时,流域土壤侵蚀与模型计算结果的变化趋势基本一致。(3)植被覆盖对土壤侵蚀面积比例和变化速率的贡献率分别为13.67%和24.55%,而降雨作用达到86.33%和75.44%,表明降雨是流域土壤侵蚀的主要动力和控制因子,降雨变化主导着流域土壤侵蚀变化过程。 相似文献
96.
97.
Effects of extreme floods on macroinvertebrate assemblages in tributaries to the Mohawk River,New York,USA
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Climate change is forecast to bring more frequent and intense precipitation to New York which has motivated research into the effects of floods on stream ecosystems. Macroinvertebrate assemblages were sampled at 13 sites in the Mohawk River basin during August 2011, and again in October 2011, following historic floods caused by remnants of Hurricane Irene and Tropical Storm Lee. The annual exceedance probabilities of floods at regional flow‐monitoring sites ranged from 0.5 to 0.001. Data from the first 2 surveys, and from additional surveys done during July and October 2014, were assessed to characterize the severity of flood impacts, effect of seasonality, and recovery. Indices of total taxa richness; Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness; Hilsenhoff's biotic index; per cent model affinity; and nutrient biotic index‐phosphorus were combined to calculate New York State Biological Assessment Profile scores. Analysis of variance tests were used to determine if the Biological Assessment Profile, its component metrics, relative abundance, and diversity differed significantly (p ≤ .05) among the four surveys. Only total taxa richness and Shannon–Wiener diversity increased significantly, and abundance decreased significantly, following the floods. No metrics differed significantly between the July and August 2014 surveys which indicates that the differences denoted between the August and October 2011 surveys were caused by the floods. Changes in taxa richness, EPT richness, and diversity were significantly correlated with flood annual exceedance probabilities. This study increased our understanding of the resistance and resilience of benthic macroinvertebrate communities by showing that their assemblages were relatively impervious to extreme floods across the region. 相似文献
98.
Do Alluvial Sand Dunes Create Energetic Refugia for Benthic Fishes? An Experimental Test with the Endangered Pallid Sturgeon
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River modifications have altered critical habitats for fishes at a variety of spatial scales and caused global declines of many fluvial species. At small spatial scales (<1 m2), alluvial sand dunes, a ubiquitous habitat in highly modified rivers, are thought to provide energetic relief for benthic fishes in energetically costly riverine landscapes created by water flow. However, use of alluvial dune habitat is not well understood, and it is unclear whether dunes provide refuge that effectively reduces energetic costs. We designed a scale‐relevant experiment to examine the energetic responses associated with sand dune habitat in rivers. We tested whether the US federally endangered pallid sturgeon (Scaphirhynchus albus ), a benthic fish commonly associated with sand dunes, experienced reduced energetic costs with different configurations of simulated sand dune habitat. We quantified mass specific oxygen consumption (M O2; mg O2 kg?1 h?1) using intermittent flow‐through respirometry for age‐0 sturgeon (140–170 mm) in front of a sand dune, behind a sand dune and in the absence of a sand dune at two velocities (25 and 50 cm s?1) commonly observed in field studies of sturgeon habitat use. Sturgeon displayed distinct station holding behaviours for each habitat configuration. Dune location did not affect energy expenditure, but sturgeon M O2 was on average 16–20% higher in the absence of a sand dune depending on dune configuration. M O2 was on average 14% higher at 50 cm s?1 compared with 25 cm s?1. Our results provide a potential mechanism for over two decades of research on why sturgeon and other benthic fishes exhibit selection for sand dune habitat in large rivers. Fishes that select main channel habitats may depend on energetic relief provided by sand dunes, especially when other forms of structure are not available. For this reason, alluvial sand dune habitat may be important to the persistence of benthic fishes in high flow environments. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
99.
Longitudinal and temporal water temperature patterns in the Yangtze River and its influence on spawning of the Chinese sturgeon (Acipenser sinensis Gray 1835)
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In this study, water temperature longitudinal and temporal patterns were investigated in four locations of the Yangtze River to identify their influence on spawning of the Chinese sturgeon (Acipenser sinensis Gray 1835). The results showed that, historically (1960–1980), the four locations, Pingshan (PS, 2,687 river kilometres [rkm]), Yichang (YC, 1,640 rkm), Chenglingji (CLJ, 1,265 rkm), and Hukou (HK, 805 rkm), all had similar average annual water temperatures (around 18.0 °C) but very different amplitudes: The upper two locations, PS (11.4–23.2 °C) and YC (9.1–25.9 °C), were relatively stable and had smaller amplitude than the lower two ones, CLJ (6.0–30.0 °C) and HK (5.9–30.8 °C). On the basis of the physiological effects for Chinese sturgeon, we defined three water temperature ranges: stressing (>23 °C), holding (23–20 °C), and spawning (20–16 °C). We found that the upper two locations with successful spawning of the Chinese sturgeon (PS and YC) had short or no stressing period but long holding and spawning periods. Currently (2013–2016), the impoundment of the Three Gorges Reservoir increases the time for water temperature decreasing to 20 °C at the current spawning ground (YC) in autumn, which increases the stressing and holding periods, and has significant negative impact on the spawning of Chinese sturgeon. Nonetheless, considering the very high stressing temperature and the short duration of the holding and spawning periods at CLJ and HK, we propose that YC is still the most suitable spawning location for the Chinese sturgeon. 相似文献
100.
《Expert systems with applications》2014,41(2):644-654
This study aims to improve the general flood vulnerability approach using fuzzy TOPSIS based on α-cut level sets which can reduce the uncertainty inherent in even fuzzy multi-criteria decision making process. Since fuzzy TOPSIS leads to a crisp closeness for each alternative, it is frequently argued that fuzzy weights and fuzzy ratings should be in fuzzy relative closeness. Therefore, this study used a modified α-cut level set based fuzzy TOPSIS to develop a spatial flood vulnerability approach for Han River in Korea, considering various uncertainties in weights derivation and crisp data aggregation. Two results from fuzzy TOPSIS and modified fuzzy TOPSIS were compared. Some regions which showed no or small ranking changes have their centro-symmetric distributions, while other regions whose rankings varied dynamically, have biased (anti-symmetric) distributions. It can be concluded that α-cut level set based fuzzy TOPSIS produce more robust prioritization since more uncertainties can be considered. This method can be applied to robust spatial vulnerability or decision making in water resources management. 相似文献