System for Surveying the River-bed Protection and River Revetment by Using Small-size Auto-going Vessels

The natural rivers and their flood areas are among the most complex and diverse ecosystems in the world. Traditional structural solutions in river training works are focused on basic requirements as flood protection, littoral zone protection, river bed protection, providing the space for economic development. In this study a method of anticipated assessment of certain physical impact of designed river training works is presented, perceived as global effect of river bed artificialization. The method mainly serves to compare the various possible solutions of river training works, based on the ?artificialization parameter? also named ?global impact GI?.

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L'enfoncement du lit de la Loire / The entrenchment of the Loire's river bed

Revue de géographie de Lyon ◽

10.3406/geoca.1994.4236 ◽

1994 ◽

Vol 69 (1) ◽

pp. 41-45 ◽

Cited By ~ 13

Author(s):

Zbigniew Gasowski

Keyword(s):

River Bed

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Distribution of nitrifying bacteria in a shallow stream

Water Science & Technology ◽

10.2166/wst.1997.0660 ◽

1997 ◽

Vol 36 (8-9) ◽

pp. 161-166 ◽

Cited By ~ 1

Author(s):

Ivana Jancarkova ◽

Tove A. Larsen ◽

Willi Gujer

Keyword(s):

Field Experiments ◽

Heterotrophic Bacteria ◽

Pollution Source ◽

Nitrifying Bacteria ◽

Channel Water ◽

River Bed ◽

Hydraulic Conditions ◽

Major Floods ◽

Shallow Stream ◽

Stream Bed

A project investigating the dynamics of self-purification processes in a shallow stream is carried out. Effects of the concentration gradient due to the distance to the pollution source, of hydraulic conditions in the river bed and of storm floods on the distribution of nitrifying bacteria were studied with the help of laboratory and field experiments. Nitrifiers density on the surface of the stream bed increased rapidly up to a distance of 300 m from the WWTP indicating possible competition of the nitrifiers with the heterotrophic bacteria close to the WWTP. Afterwards a slight decrease in the downstream direction was observed. In vertical profiles, higher bacterial densities were found at sites with rapid infiltration of channel water to the stream bed than at sites with no exchange between channel water and stream bed water or where stream bed water exfiltrated. A major flood event scoured the nitrifiers nearly totally from the surface of the river bed. Major floods belong so to the most dominant processes controlling self-purification in shallow streams. Minor floods, however, don't scour bacteria in the depth of the stream bed that could then be important for the self-purification processes.

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