In order to determine the contribution of aquatic macrophyte communities on nutrition to sustain the high primary productivity of an estuary aquatic community, we analyzed the process of phosphorus release from sediments in aquatic macrophyte community in the estuary of the Chikugogawa River, South-Western Japan. Vertical profile of 4 PO  concentration and redox potential (Eh) of pore water in...

Spring flooding of the Red River of the North (RR) is common, but little information exits on how these flood events affect water and overbank sediment quality within an urban area. With the threat of the spring 2009 flood in the RR predicted to be the largest in recorded history and the concerns about the flooding of farmsteads, outbuildings, garages, and basements, the objectives of this stud...

This study was carried out to examine heavy metals concentration in water and sediment of upstream and downstream of the entry of the sewage to the Tembi River, Iran. Samples were collected from upstream and downstream and were analyzed for Cd, Cr, Cu, Fe, Pb, Ni, and Zn by atomic absorption spectrophotometer. The results indicated that the average concentration of the metals in water and sedim...

In this paper, the sediment-laden flow around a circular cylinder is numerically simulated in order to obtain better understanding of hydrodynamics associated. A range of cases with different Reynolds numbers (Re) are studies. The effects of the concentration of the sediment on the drag coefficient are investigated. Results show that due to the fact that the laden sand particle colliding the cy...

To assess the environmental radioactivity levels and hence to determine the population exposure in Kutubdia Island, Bangladesh the sediment samples were analyzed by using gamma ray spectrometry. In those sediment samples the average activity concentration of natural radionuclides 238U, 232Th and 40K were found 15.39±1.67, 38.35±0.76 and 475.51±21.15 Bq/kg respectively. ...

Significant concentrations of oxalate (dissolved plus particulate) were present in sediments taken from a diversity of aquatic environments, ranging from 0.1 to 0.7 mmol/liter of sediment. These included pelagic and littoral sediments from two freshwater lakes (Searsville Lake, Calif., and Lake Tahoe, Calif.), a hypersaline, meromictic, alkaline lake (Big Soda Lake, Nev.), and a South San Franc...

The Importance of dissolved versus sediment-bound cadmium as uptake routes for the deposit-feeding polychaete Capitella species I and the toxicity and toxicokinetlcs of cadmium from these exposure routes were investigated. Effects were reported as changes in worm growth rate, egestion rate and allometry. Radioactive cadmium (""'Cd) was used as a tracer to examine the uptake (5 d) and subsequent...

abstract nowadays, measuring water quality is very important for comprehensive management of water resources. suspended sediment is one of the most important water quality factors which greatly affects environment health. however, its measurement needs too much time and money. it was therefore tried in the present study to assess the applicability of modelling relationship between suspended sed...