A high prevalence of intersex or testicular oocytes (TO) in male smallmouth bass within the Potomac River drainage has raised concerns as to the health of the river. Studies were conducted to document biomarker responses both temporally and spatially to better understand the influence of normal physiological cycles, as well as water quality and land-use influences. Smallmouth bass were collecte...

Bidirectional flows in a river system can occur under stratified flow conditions and in addition to creating significant errors in discharge estimates, the upstream propagating currents are capable of transporting contaminants and affecting water quality. Detailed field observations of bidirectional flows were made in the Chicago River in Chicago, Illinois in the winter of 2005-06. Using multip...

Estuaries are well known for their potential in removing metal from fresh water to provide micro-nutrients to aquatic life. In the present investigation, we have tried to bring out the metal removal potential of estuaries during accidental spills. For this purpose artificial river water containing high concentration of Mn, Cu, Zn, Ni and Pb were mixed with sea water at different salinity regime...

This study investigates the turbulent flows in simplified Dragon style river channels with a constant critical curvature and different single-short-branch characteristics, using an effective numerical method based on real geometry statistics. First, when branch outlet is closed, main channel, strong bed shear stresses are concentrated at inner bend apex downstream; as widens, more flow enters b...

We estimated the timing of paleodrainage connections in the Colorado River Basin using mitochondrial deoxyribonucleic acid (DNA) sequence divergences among populations of the speckled dace, Rhinichthys osculus. Cytochrome b and ND4L sequences were analyzed by maximum likelihood methods to estimate phylogenetic branch lengths, which were calibrated to geological time with a fossil age estimate. ...

SUMMARY A small remnant of native forest and scrub located in the upper East Branch of the Tokomairiro River is described and assessed for ecological significance. Vegetation grades from pasture on rolling ridges through bracken, Himalayan honeysuckle, gorse and broom scrub on upper gully slopes, to a mosaic of forest types characterised by kanuka, common broadleaved species, or narrow-leaved l...

The geochemical processes of mercury in Dongfeng (DF) and Wujiangdu (WJD) reservoirs, which were constructed in 1992 and 1979, respectively in Wujiang River, which is the upper branch of Yangtze River were investigated. One sampling site was chosen up river of 1 km from the dam for each reservoir. Three sampling campaigns were conducted at these sampling sites in December 2003, April 2004 and J...