Main, river

These appHcations require withdrawal of water from a source and subsequent treatment and conveyance to the point of use. Water is also used without being withdrawn from a source, eg, for navigation, recreation, wild and aquatic life propagation, hydroelectric-power generation, and waste assimilation and transport. The principal types of withdrawal uses and their average rates are given in Table 2. Some of these withdrawal rates represent multiple uses of the same water along main rivers in metropoHtan and industrialized areas. 

More than 80% of Moldavia s bodies of water in 1985-86 were dangerously contaminated with pesticides. The level of pesticide contamination was high in the main rivers of Ukraine the concentrations of DDT and its metabolites in the Dnepr reached 0.384 mkg/l [23]. 

The Cantabrian Mountains and the Pyrenees in the North, the Iberian System in the South-East, and the Coastal Catalan mountains in the East are the natural limits of the Ebro River basin. Traditionally, the river source was supposed to be at Fontibre (name derived from Forties Iberis in latin, Springs of Iberia ) at 880 m.a.s.l., near Reinosa in Cantabria. Nowadays, the river source is placed at 1,980 m.a.s.l., the water coming from a source in Penalara (27 km upstream from Reinosa). The main river channel is 910 km in length, flows NW-SE, from the Cantabrian Mountains to the Mediterranean Sea, where it forms a delta. 

Main rivers discharging in each site are Panuco, Carrizal and Soto La Marina. 

While the daily averages in the phase influenced by power plants exhibit significantly less variabihty, a very different daily runoff pattern is often observed during the day, short-term surges and downsurges (hydropeaking) can be observed over wide sections of the main rivers. This artificially induced high water impacts... 

In The Netherlands locally found clay is almost exclusively used as main raw material. The most important clay deposits for (paving) bricks are found along the river banks of Holland s main rivers. River clay from the polders is mostly fat to very fat and deficient in lime consequently it is used in the production of e g. roof tiles. We call a clay type fat when it contains a high percentage of minute particles. The Dutch coarse-ceramic clay is a sediment, appr. 45 % of whose particles have a diameter of < 10 pm. The coarser sand and silt fractions... 

Table 10.1. Pesticide residue levels in water samples from main rivers in Thailand, 1985-1988 (Source Thapinta and Hudak, 2000)...

During the first phases of the delta development, the main river flow ran to the sea along the southern boundary of the delta (the Gheorghe branch at present). Then the ancient Sulina branch was formed. Only by the 18th century, after filling up the shallow inland parts of the former bay by river sediments, formation of the marine protruding Chilia delta in the open nearshore zone started. This event took place around 1740s. The most active... 

With regard to a river system, it is of interest to monitor water quality along the main river and establish the salt and pollution contribution by each tributary. This is a promising way to detect pollution sources in due time. 

Answer 18.4 A station at each river tributary before it reaches the main river and a number of stations along the main river. Does this make sense ... 

Konovalov, G.S., Ivanova, A.A. and Kolesnikov, T.Kh., 1968. Disseminated and rare elements dissolved in the water and contained in the suspended matter of the main rivers of U.S.S.R. In Geokhimia osadochnykh porod i rod (Geochemistry of Sedimentary Rocks and Ores). Izd. Nauka, Moscow, pp. 72-87 (in Russian). 

Overall, these results suggest a general pattern of carbon flow in lakes on the central Amazon floodplain. Nutritious plant materials, primarily derived from C-3 plants (phytoplankton, periphyton, C-3 macrophyte leaves, tree fruits, and seeds) are selectively consumed by aquatic herbivores and detritivores and dominate the organic carbon flow to higher trophic levels. Some C-3 plant materials and the bulk of C-4 plants decompose and release their organic carbon, predominantly in the dissolved form, to the water column. The labile component of this DOC, dominated by C-4 plant carbon, is rapidly consumed by heterotrophic bacterial communities and released as either CO2 or CH4 to the atmosphere. The more refractory DOC component has a much slower turnover rate and tends to persist in the system where it is eventually exported to the main river channel. 

The ultimate source of Hawkins River is not known because the main river sumps a short distance upstream from the confluence. The Hawkins River sediments are more uniformly distributed over the range of silt to gravel with less than 10% of the material smaller than the smallest sieve size used. 

Andreae and coworkers analyzed two polluted rivers in Germany for inorganic and methylated antimony compounds . Sb(III), Sb(V) and methylstibonic acid in the Rhine River at Oppenheim and the Main River at Frankfurt were 0.4, 231.0 and 1.2, and 0.3, 311.0 and 1.8 ppb, respectively. Dimethylstibinic acid was not detected. 

The two main rivers that divide the country cire the Niger eind Benue. The Kaduna Sokoto and Ogun rivers similarly drain the land and facilitate agriculture. 

The spectra of the lake must be related to the ones of its main tributaries (Figure 2.4.12). Only one tributary brings almost 90% of water to the lake, but to upstream main rivers (tributaries 4 and 6) are contributing to the main tributary. The... 

The four main river basins are placed on this area Amur, Huanghe, Yangtze and Mekong rivers. There are also plenty of middle and small rivers in East Asia. These rivers are drained into East (Japan), Yellow, East China and South East China Seas of the Pacific ocean. 

The local water transport in the delta constituted motor vessels owned by different organizations. These motor vessels with a draught of 3 m ran along certain routes. In the seashore part of the delta motor vessels of fishery organizatiOTis represented the main transportation mode. In the inner parts of the delta the navigation was mostly developed in the main river channel and its main branches, such as Kipchakdarya and Akdarya and also in the largest arm Raushan [4],... 

Zhanadarya, Kuvandarya) and the Amudarya (Daudan) in the nineteenth century, concentrating the flow of water to the main river beds. 

Staffordshire remained poor up to the eighteenth century, despite its rich stores of mineral wealth, notably iron and coal. The lack of communication between this county and the rest of England was an obstacle to industrial and commercial development of Staffordshire. It was shut in on the north by tracts of moorland and limestone hills, with the wooded Cannock Chase on the south, and the Welsh mountains as a barrier in the western direction. The Trent, the main river in Staffordshire, rises in the north of the county, but only from the neighborhood of Burton-upon-Trent, on the eastern boundary of the county, was river navigation of any consequence. There was no way of reaching the western seaboard by water until the cutting of canals in the eighteenth century. 

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