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101.
胡盛斌 ' target="_blank" rel="external"> 杜国平 ' target="_blank" rel="external"> 徐国元 钟有信 杜广林 《中国安全生产科学技术》2019,15(2):51-56
针对复杂水文地质条件的地铁区间隧道联络通道涌水风险,引入声纳渗流技术探测联络通道区域内地下渗流场特征,采用三维流速矢量声纳测量仪分别进行洞内无损探测和地表井孔测量,综合判断探测区域内的渗流场分布规律。研究结果表明:声纳渗流技术可以在水文地质勘察和涌水渗漏治理中应用,快速准确地测量渗水路径、补给来源以及流速、流向、流量、渗透系数等量化指标,以此建立地下渗流场三维可视化云图,科学指导工程降水设计、涌水渗漏处理,并能验证注浆堵漏处理效果,提前防控暗挖隧道涌水渗漏风险,可为类似工程的安全风险管控提供借鉴和参考。 相似文献
102.
闽江福州段与城市内河表层沉积物重金属污染特征研究 总被引:2,自引:0,他引:2
为了探讨城市内河对闽江福州段重金属污染的影响特征,本文对闽江福州段和福州城市主要内河表层沉积物中的Cr、Ni、Cu、Zn、As和Pb 6种重金属元素进行了系统的分析,并采用地累积指数法和潜在生态风险评价法进行污染情况和潜在危险评估.研究结果表明,表层沉积物中重金属Cr、Ni、Cu、Zn、As和Pb含量范围分别为:5.55~131.35、0.74~138.82、2.45~95.84、24.24~609.72、2.82~95.90、13.91~108.45mg·kg~(-1),各重金属含量平均值明显高于福建省土壤环境背景值,但低于国家土壤环境质量Ⅱ类标准值(除As略高于Ⅱ类标准).地累积指数法评价结果表明,表层沉积物中重金属大多为无污染或中污染程度,受人类活动影响强烈.潜在生态风险评价法表明,表层沉积物中重金属Cr、Ni、Cu、Pb和Zn存在轻微潜在风险,As以中等潜在风险为主,总体存在轻微潜在风险.重金属污染物的空间分布与福州市的发展格局相适应,人类活动集中的老城区和工业密集区,是闽江与内河重金属污染物含量相对较高的区域.城市内河汇入闽江后,携带的大量重金属污染物加剧了闽江重金属污染.建议加强对闽江重金属含量较高的晋安河段、光明港段-磨溪河段的污水排放监控. 相似文献
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Riprap, consisting of large boulders or concrete blocks, is extensively used to stabilize streambanks and to inhibit lateral erosion of rivers, yet its effect on river morphology and its ecological consequences have been relatively little studied. In this paper, we review the available information, most of it culled from the “grey” literature. We use a simple one‐dimensional morphodynamic model as a conceptual tool to illustrate potential morphological effects of riprap placement in a gravel‐bed river, which include inhibition of local sediment supply to the channel and consequent channel bed scour and substrate coarsening, and downstream erosion. Riprap placement also tends to sever organic material input from the riparian zone, with loss of shade, wood input, and input of finer organic material. Available information on the consequences for the aquatic ecosystem mainly concerns effects on commercially and recreationally important fishes. The preponderance of studies report unfavorable effects on local numbers, but habitat niches created by openings in riprap can favorably affect invertebrates and some small fishes. There is a need for much more research on both morphological and ecosystem effects of riprap placement. 相似文献
106.
介绍了1995年日本阪神7.2级地震造成的河流损害、防止次生灾害采取的紧急对策及修复方案,以供我国研究防御地震次生灾害参考。 相似文献
107.
David G. Smith Robert J. Davies-Colley Jeroen Knoef Gerritdina W. J. Slot 《Journal of the American Water Resources Association》1997,33(2):301-312
ABSTRACT: Six years (1989–1994) of data from New Zealand's National Rivers Water Quality Network were used to characterize the optical water quality regime of river waters as regards: visual clarity (black disc visibility), turbidity, and light-absorbing aquatic humic material (referred to as ‘yellow substance,’ measured as light absorption at 440 nm). Quantitative relationships between optical water quality variables and flow in rivers are well-described by power law expressions. Visual clarity usually decreases strongly with increasing flow in individual rivers. There is a strong, inverse relationship between turbidity and visibility, but, because of differences between sites, turbidity is not a good general predictor of visual clarity (the attribute of real interest) in rivers. Yellow substance tends to increase with increasing flow, probably because during rainstorms, soil water high in yellow-colored humic material, rather than rain water or ground water, dominates discharge. Therefore, rivers are typically clear and low in humic matter at low flow, and turbid and yellow-colored at high flow. 相似文献
108.
Jill M. Noel Robert H. Chamberlain Alan D. Steinman 《Journal of the American Water Resources Association》1995,31(1):21-32
ABSTRACT: A study was initiated to examine the effects of wind speed, wind direction, freshwater inflow, and tide height on suspended solid concentration and distribution in the Loxahatchee estuary, Florida. Recent efforts to increase freshwater flows in this system raised concerns that suspended solid concentrations would increase as well, which might result in negative impacts for the estuary. The data indicated that total suspended solids (TSS) in the estuary are derived primarily from the inlet and not from freshwater tributaries. In addition, total suspended solids and volatile suspended solids were correlated strongly with salinity, suggesting that suspended sediments act conservatively throughout this system. No one environmental factor had an overwhelming influence on suspended solid concentration throughout the estuary; different regions of the estuary were influenced by different factors. Freshwater inflow was negatively related to TSS in the upper reaches of the estuary but was positively related to TSS in the central embayment region of the estuary. We attribute this latter finding to the fact that extremely high inflows both prevented the normal transport upstream of tidal borne suspended sediments and promoted mixing when the freshwater front moving downstream confronted the tidal front moving upstream. Wind speed, wind direction, and tide height had relatively small effects on TSS concentration but were most influential in reaches upstream of the central embayment, where tidal velocity begins to diminish. 相似文献
109.
Richard M. Vogel Neil M. Fennessey 《Journal of the American Water Resources Association》1995,31(6):1029-1039
ABSTRACT: A streamflow duration curve illustrates the relationship between the frequency and magnitude of streamflow. Flow duration curves have a long history in the field of water-resource engineering and have been used to solve problems in water-quality management, hydropower, instream flow methodologies, water-use planning, flood control, and river and reservoir sedimentation, and for scientific comparisons of streamflow characteristics across watersheds. This paper reviews traditional applications and provides extensions to some new applications, including water allocation, wasteload allocation, river and wetland inundation mapping, and the economic selection of a water-resource project. 相似文献
110.
Lowell E. Keup 《Journal of the American Water Resources Association》1985,21(2):291-296
Using data related to stream order and the morphological characteristics associated with streams of different discharge rates, an estimate of the river resources of the United States is made. The national totals are: 3,200,000 miles total length of rivers; 15,000 square miles of river surface; and 29 cubic miles of water stored in river channels. Using the same techniques, more exact estimates may be made for individual river basins. Suggestions are given for application of the techniques and river data in the management of water resources. 相似文献