objective: zayandehrood habitat has economical and environmental importance in central plateau of iran    and it performs a vital role for habitants, agriculture section and the industries which are located along river bed. so current research  has been done to measure the contamination of heavy metals, its changes along the river route and defining the important and effective regions on this c...

The size and shape of the stones in dry gravel river beds are of interest in geology and river hydraulics. The topography of a bed surface can be measured by three-dimensional laser scanning. A method is described for fitting ellipsoids to the surfaces of individual stones to estimate their size, shape and orientation in the river bed. Different cost functions are evaluated and the methods are ...

Representative bed material samples were taken from the two gauging sites on rivers omi for sieve analysis to obtain the grain size distribution of its bed materials. The analyses of the grain size distribution showed that the bed load accounted for 9% of the total estimated suspended sediment load of 1,703, 548.113 kg/annum in river omi. River omi bed material had a geometric mean particle siz...

abstract morphological river models are designed to provide physical insight into the morphological response and to assist river engineers and managers in the design, operation and maintenance of river systems. here deterministic modeling weak for a dynamic and stochastic of nature river environment. specially, these could not predict the exact shape of the river bed, specially e.g. for braided...

movement of sediment in the river causes many changes in the river bed. these changes are called bedform. river bedform has significant and direct effects on bed roughness, flow resistance, and water surface profile. thus, having adequate knowledge of the bedform is of special importance in river engineering. several methods have been developed by researchers for estimation of bed form dimensio...

The lowermost Mississippi River, defined herein as the river segment downstream of the Old River Control Structure and hydrodynamically influenced by the Gulf of Mexico, extends for approximately 500 km. This segment includes a bedrock (or more precisely, mixed bedrock-alluvial) reach that is bounded by an upstream alluvial-bedrock transition and a downstream bedrock-alluvial transition. Here w...

knowledge of habitat requirements of aquatic animals plays an important role in fisheries and protection programs of aquatic ecosystems. hence, this study was conducted to investigate the suitability indexes of habitat use and habitat suitability index (hsi) of barbus cyri in its distribution range in tootkabon river. a number of environmental variables, including elevation, water depth, river ...