TODOR MISHONOV, STEFAN-LUDWIG DRECHSLER and EVGENI PENEV † Laboratorium voor Vaste-Stoffysica en Magnetisme, Katholieke Universiteit Leuven Celestijnenlaan 200 D, B-3001 Leuven, Belgium Department of Theoretical Physics, Faculty of Physics, Sofia University “St. Kliment Ohridski” 5 J. Bourchier Blvd., 1164 Sofia, Bulgaria Institut für Festkörperund Werkstofforshung Dresden, D-001171 Dresden, Ge...

This study provides an extensive dataset of dissolved trace metals (silver, cadmium, copper, nickel, lead, iron, and zinc), inorganic (ammonia, nitrate, phosphate and silicates), and organic (urea, dissolved organic nitrogen, carbon and phosphorous, as well as particulate carbon and nitrogen) constituents during high and low riverine flow conditions in surface waters of the Long Island Sound. A...

The use of riverine dissolved organic matter by the heterotrophic bacteria associated with a culture of the cyanobacterium Microcystis aeruginosa and release of simple nitrogen compounds were studied in an experimental series. Bacteria reduced the bulk of dissolved organic nitrogen (DON) by half, but when associated with M. aeruginosa, DON was excreted and its concentration rose by 13%. During ...

The biological variables consist of a single population each of phytoplankton and grazers, which are denominated in phosphorus units (mmol m23) in the constant (Redfield) ratio model (CRM) and are given the symbols Pp and Pz. In the variable ratio model (VRM), there are separate state variables for phytoplankton carbon (Cp), nitrogen (Np), phosphorus (Pp), and chlorophyll (M). Grazer biomass is...

As part of the efforts to ensure adequate supply of quality water from Danjiangkou Reservoir to Beijing, surface water samples were taken from the tributaries of Danjiangkou Reservoir in the normal (May), flood (August) and dry (December) seasons of 2014, and characterized for nitrogen and phosphorus contents as specified in the applicable standards. Test results indicated that (i) the organic ...

We examined the ability of seagrasses to take up dissolved organic nitrogen (DON) with leaves (in situ) and roots (laboratory) in an oligotrophic tropical offshore meadow in Indonesia using 15N-labeled nitrogen (N) substrates. We compared the uptake of urea and amino acids with that of ammonium (NH z4 ) and nitrate (NO { 3 ) and determined uptake kinetics of amino acids for the seagrasses Thala...

The great diurnal variation in the quality of wastewater of small communities is an obstacle to the efficient removal of high nitrogen with traditional activated sludge processes provided by pre-denitrification. To verify this problem, the authors developed a pilot plant, in which the domestic wastewater of community of 15,000 inhabitants was treated. The results demonstrate that average and pe...

A study was conducted to evaluate the correlation between selected physico-chemical parameters of water and their effects on growth of Rainbow trout (Oncorhynchus mykiss) in raceway system in the area of Sarab Gerdu, Iran. The samples were collected from twenty raceways (270- day old fish, surface area 55m2 flow rate 150 ls-1 total production 15 T). Physico-chemical parameters were the fluctuat...

The Amazon River estuary is notable at the Amazon Continental Shelf, where the presence of the large amount of water originating from the Amazon during the river's falling discharge period was made evident by the low salinity values and high nutrient levels. Even so, the presence of oceanic waters in the shelf area was significant. Dissolved organic nitrogen was the predominant species of the n...

In order to evaluate the effects of different slope lengths (1, 2, 3, 4, and 5 m) and different vegetation coverage ratios (20%, 45%, 60%, and 90%) on the mechanisms of nutrient loss and runoff producing processes, we have conducted 14 simulated rainfall experiments. The results show that N and P loss are decided by the concentration and the runoff volume, but when the amounts of N and P in top...