TOPOLOGICAL VALIDATION: A STUDY APPLIED FOR HYDROGRAPHIC FEATURES OF A WATERSHED

Author(s):  
Leandro Luiz Silva de França ◽  
Joel Borges dos Passos ◽  
Jose Luiz Portugal
1959 ◽  
Vol 16 (3) ◽  
pp. 351-361 ◽  
Author(s):  
Paul N. Sund

Zooplankton collections from two cruises to the Gulf of Alaska during 1954 and 1956 were studied to determine the species of Chaetognatha present, to establish their distribution within those waters, and to consider the distribution of the species with regard to certain general hydrographic features prevalent in the region at the time the collections were made. Also considered were a few collections made during the summer of 1958 in the waters surrounding San Juan Island in the San Juan Archipelago, Washington.The general oceanographic features of the Gulf of Alaska are described. The distributions and frequency of occurrence of 3 species of 2 genera of chaetognatha are described and discussed. Eukrohnia hamata is found at most off-shore stations, diminishing in number nearer the coast in less saline waters. Sagitta elegans is apparently cosmopolitan in the areas studied. S. lyra an oceanic form, was found in regions influenced by waters of the Subarctic Region and the American Coastal Region. The presence of S. lyra in inland waters of the San Juan Archipelago during the summer of 1958 is considered to be an indication of the shoreward movement of oceanic waters.


2016 ◽  
Vol 1 (14) ◽  
Author(s):  
Milan Trifković ◽  
Goran Marinković ◽  
Boban Ilić ◽  
Goran Pejičić ◽  
Jelena Lazić

The Municipality of Velika Plana has been taking serious steps when it comes to initiating landconsolidation projects which help realize the land reclamation projects in the simplest way. Whit theaim of obtaining the base for carrying out land reclamation projects, this work deals with and presentsthe survey of the hydrographic features of Municipality of Velika Plana, as well as, water regime andthe river basin of the Velika Morava River. Based on measuring data obtained at Ljubicevski most,water gauge survey station we have performed and presented the analysis of the distinctive annual flowover a longer period of time as well as the analysis related to the changes in parameters which occur onan annual basis. On the basis of performed analysis we have been able to determine the amounts ofwater for irrigation available in the Velika Morava River basin at the territory of Velika Plana, whichwas the main focus and objective of this research.


Author(s):  
A. S. Shtanko ◽  
◽  
V. N. Shkura ◽  

Purpose: development of layout and design schemes for low-flow water intakes, arranged on shallow river and stream watercourses for supplying water to drip irrigation systems. Agricultural development of terraces and floodplains of small foothill and mountain streams actualizes the development of facilities for water intake from them for the purpose of irrigating land. Morphological and hydrographic features, including shallow low-water depths, high flow rates, flow rates variability, saturation with sediments, the presence of underflow and overflow runoff, etc., make water intake from such watercourses difficult and specific. These circumstances predetermine the relevance of water intake structures development corresponding to the specified conditions. Materials and Methods. When developing the layout and design schemes of low-flow water intakes from shallow watercourses, the technologies of exploratory design of engineering systems and structures were used. Results. With regard to the morphometric, hydrological and other conditions of shallow foothill and mountain streams, a water intake with a bottom water intake was adopted for development. The water intake part of headworks is designed in the form of a toe drain, which has under-flow and overflow intake parts that allow water intake from the channel and off-channel water streams. The toe is made of two or three layers of sand and gravel material. Drainage pipes or pipe filters are used as a drainage element. Depending on the conditions of the watercourse, water intakes with transverse, longitudinal and pocket-coastal placement of water intakes are proposed. Conclusion. The layout and design schemes of filtering water intakes from shallow watercourses based on the use of overflow, underflow and combined structures of multilayer drainage water intakes with stream (transverse and longitudinal) and off-channel (pocket-coastal) placement have been proposed and developed.


Author(s):  
J.R. Siddorn ◽  
J.I. Allen ◽  
R.J. Uncles

A 3-D hydrodynamic model of the circulation, salinity and temperature within the embayment of Plymouth Sound, UK and its surrounding English Channel waters has been implemented. Thorough validation of the model shows that the main hydrographic features of the region, as characterized by these variables, are reproduced. The general flow characteristics, and the resultant distribution of freshwater from the main riverine source (the River Tamar), are described. The potential fate of contaminant releases within Plymouth Sound is investigated. Whitsand Bay, located south-west of Plymouth Sound, is shown to be a likely recipient for a proportion of these contaminants, irrespective of where in the Sound the release occurs, and as such is considered to be vulnerable to pollution events originating there.


2019 ◽  
Vol 63 ◽  
pp. 05002
Author(s):  
Nelly Cattaneo

In the early 20th century the agrarian policies of the Colonial Government in Eritrea moved from the promotion of Italian family homesteads on the highlands to the exploitation of wide semi-arid areas in the lowlands. In particular the surroundings of Tessenei, close to the Sudanese border, for its geomorphological and hydrographic features, were appropriate for a wide intensive plantation of cotton. Here in 1905 the most meaningful intervention of colonial agrarian valorisation in Eritrea was being planned, but it was realized at the end of the Twenties. Barriers, embankments, canals and drains caused then a radical change in the landscape, imposing a severe geometry over 10.000 hectares of smoothly corrugated lands around the Gash River. Production activities were mainly based on local workers: this had a dramatic impact on traditional culture and social relations, stressed by the fact that in a short while migration from Sudan and Ethiopia was encouraged. By analysing the main features of the spatial organization designed in Tessenei, an attempt to outline the relation between the colonial government and local cultural system will be made; the comprehension of this relation would be important to understand the legacies of the project and its potentialities at present.


ARCTIC ◽  
1998 ◽  
Vol 51 (3) ◽  
Author(s):  
Fridtjof Mehlum ◽  
George L. Hunt, Jr. ◽  
Mary Beth Decker ◽  
Nina Nordlund

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