River floods, impact

Point and diffuse sources contribute to heavy metals in sediments. Point sources have dominated the input of heavy metals in surface vaters for most of the past century, and both dated sediment cores and archived sediment samples sho v the impact of uncontrolled industrialization between 1900 and 1970 on sediment composition. Although these point sources are no longer in existence, or they have reduced their output due to regulations, these contaminated sediments are still present in the environment and pose an important management issue of clean-up. Important in this respect are river flood plains and dredging and disposal of old sediments in locks, weirs, and river stretches. In this chapter, the available technologies for clean-up or... 

Ice and hail, snow, etc. can cause a loss of off-site power. The reactor building was designed to withstand blast pressure of 1,000 Ibs/ft can withstand tornado missile impact (Sharp, 1986). A tornado could damage the reactor by hitting the river water pump houses similar to the flooding scenario. 

China, the Colorado in the United States, and the Nile in Africa, are only some of the most famous examples. The construction of dams along these rivers allows flood control, and water for irrigation and power, but the retention of sediment behind the dams severely impacts some of the richest and most productive ecosystems in the world. 

Soil with elevated content of these elements occurs along the Sacramento River in both levee and adjacent flood basin settings. We interpret that transport of sediment impacted by large metal sulfide mines located in the Klamath Mountains at the north end of the Valley has caused this pattern. 

Desertification is caused by overcultivation, overgrazing, and deforestation. This may result in soil exhaustion and erosion. This will in turn decrease the soil productivity, reduce food production, deprive the land of its vegetative cover, and negatively impact areas not directly affected by its symptoms, by causing floods, soil salinisation, deterioration of water quality, and silting of rivers, streams, and reservoirs (http //www.fao.org). 

Observations show that the area of hypoxia directly depends on volume of the Danube water runoff during spring-summer flood. Besides, this area depends on the time of the flood peak [9,31]. If the flood peak takes place in April, the river fresh waters are driven out of the northwestern part of the Black Sea in the south direction under the influence of predominated northern winds in this time, and hypoxia is absent. Other situation takes place if the flood peak falls on May or June, when under the impact of the southern winds, main mass of river fresh water remains in the northwestern part of the Black Sea. In this case, hypoxia forms later and in the area between the Danube and Dniester mouths [9,31]. 

Sunderraj, W. and Johnsingh, A.J.T. (1996). Impact of Flash Flood on the Gallery Forest and arboreal mammals of river Servalar, Mundanthurai Plateau, South India. Journal of Wildlife Research, 1 89-94. 

Barber L, Writer JH (1998) Impact of the 1993 Flood on the Distribution of Organic Contaminants in Bed Sediments of the Upper Mississippi River. Environ Sci Techn 32, 2077-2083. 

Finally, mean discharge values for rivers cannot reflect short-term events, nor do they necessarily reflect the flux for a given year. Floods (often related to the El Nino/La Nina events) can have particularly large impacts on smaller and/or arid rivers, such that mean discharges or sediment loads may have little relevance to short-term values. Despite these caveats, mean values can offer sedimentologists and geochemists considerable insight into the fluxes (and fates) from land to the sea. 

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