sediments from the southern caspian sea, located in iranian coast were examined on the basis of p-fractionation (five forms of phosphorus) by a sequential extraction scheme. ninety-six surface sediment samples (for each season with triplicate) were collected from eight sampling transects in 10 and 100 m depths during summer and winter in 2010-2011. the result indicated that the most abundant fo...

Efforts to reduce phosphorus concentrations in aquaculture systems have mainly dealt with improving the bioavailability of phosphorus in fish feed. Once released into the culture water, phosphorus is generally left untreated and discharged with the effluent water. In the present study, results are presented on a prototype recirculating treatment system originally designed for removal of organic...

A new model has been developed for assessing the effects of multiple sources of phosphorus on the water quality and aquatic ecology in heterogeneous river systems. The Integrated Catchments model for Phosphorus (INCA-P) is a process-based, mass balance model that simulates the phosphorus dynamics in both the plant/soil system and the stream. The model simulates the spatial variations in phospho...

In 1906 Emmett and Grindleyl concluded from their investigations, that the Hart and Andrews2 method for the determination of inorganic and organic phosphorus in feeding stuffs, could not be used directly for determining these different forms of phosphorus in aqueous extracts of flesh, on account of the large quantity of soluble proteins present. They concluded, however, that if the soluble prot...

Sediments from the Southern Caspian Sea, located in Iranian coast were examined on the basis of P-fractionation (five forms of phosphorus) by a sequential extraction scheme. Ninety-six surface sediment samples (for each season with triplicate) were collected from eight sampling transects in 10 and 100 m depths during summer and winter in 2010-2011. The result indicated that the most abundant fo...

Black Sea receives 1,125,839 tons of organic matter, 575,000 tons mineral nitrogen, 55,000 tons mineral phosphorus, 30,000 tons organic phosphorus, 90,000 tons iron, 206,000 tons petroleum and petroleum products, 48,000 tons surfactant, 12,000 tons zinc, 67,000 tons manganese, 4,500 tons lead, 2,800 tons copper, 900 tons cadmium and 80 tons of mercury in a year from land based sources. All thes...

Acute static bioassays were conducted with 13 pesticides to determine their comparative toxicity to fish. There was a wide range in the toxicity of these compounds with 96-hour TLm values ranging from 0.0033 to 4.0 mg/1. Of the compounds tested, Thiodan, a chlorinated hydrocarbon, and Thimet, an organic phosphorus pesticide, were the most toxic; and Bayer 29493, an organic phosphorus compound, ...

Background: Various chemical, physical and biologic treatment methods are being used to remove nitrogen and phosphorus from wastewater. Sequencing batch reactor (SBR) is a modified activated sludge process that removes phosphorus and organic material from sanitary wastewater, biologically. Methods: This study was conducted in 2016.The performance of an aerobic-anaerobic SBR pilot device, locat...