River phosphorus

Demurs BOL, Harper DM, Pitt JA, Slaughter R (2005) Impact of phosphorus control measures on in-river phosphorus retention associated with point source pollution. Hydrol Earth Syst Sci 9 43-55... 

A problem of many sewage treatment works in the UK is that urban drainage is included with domestic sewage in the sewage collection systems. The resulting storm-water discharges, at times of heavy rainfall, lead to continuing phosphorus export to the river. Correction of this problem requires considerable investment in separate systems. 

As just implied, the land-based phosphorus cycle is connected to the water-based cycle via the rivers and sewers. It has been estimated that, on a global scale, about 2 million... 

Preparation of 3 5-diiodo-4-(4 -hydroxyphenoxy)phenylacetic acid (diac) A solution of ethyl 3 5-diiodo-4-(4 -methoxyphenoxy)phenyl acetate (9.5 g) in acetic acid (60 ml) was heated under reflux with hydriodic acid (SG 1.7, 50 ml) and red phosphorus (0.5 g) for 1 hour. The hot solution was filtered and the filtrate concentrated at 50°C and 15 mm of mercury to above 20 ml. The residue was treated with water (70 ml) containing a little sodium thiosulfate to decolorize the product. The solid was collected by filtration and purified by the method of Harington and Pitt-Rivers [Biochem. J. (1952), Vol. 50, page 438]. Yield 8,36 g (95%). After crystallization from 70% (v/v) acetic acid it melted at 219°C. 

Unlike other biogeochemical elements, phosphorus does not have a significant atmospheric reservoir. Thus, while some amount of phosphorus is occasionally dissolved in rain, this does not represent an important link in the phosphorus cycle. River runoff is the primary means of transport between the land surface and oceans, and unlike the other elements discussed. 

It has been argued that phosphorus limits oceanic productivity on the million year time scale (Broecker, 1971). The reason is that essentially all phosphorus in the ocean is introduced by rivers and thus ultimately from the weathering of continental rocks. This flux is, in effect. 

In a steady-state ocean the sediment deposition rate of a nutrient like phosphorus ought to be balanced by riverbome influx to the oceans 1.5. 0Tg P are transported to the oceans by rivers (Richey, 1983). Assuming a C/P molar... 

The land biota reservoir (3) represents the phosphorus contained within all living terrestrial organisms. The dominant contributors are forest ecosystems with aquatic systems contributing only a minor amount. Phosphorus contained in dead and decaying organic materials is not included in this reservoir. It is important to note that although society most directly influences and interacts with the P in lakes and rivers, these reservoirs contain little P relative to soil and land biota and are not included in this representation of the global cycle. 

Paulsson M, Mansson V, Blanck H (2002) Effects of zinc on the phosphorus availability to periphyton communities from the river Gota Alv. Aquat Toxicol 56 103... 

Keywords Nitrogen, Nutrient retention, Phosphorus, Point sources. River, Stream, Wastewater treatment plants. Water scarcity... 

Withers PJA, Jarvie HP (2008) Delivery and cycling of phosphorus in rivers a review. Sci Total Environ 400 379-395... 

House WA, Denison FH (1998) Phosphorus dynamics in a lowland river. Water Res 32 1819-1839... 

An unusual example of a process that produces a lot of waste is the intensive rearing of pigs. They need additional phosphorus in their feed for healthy growth, and this is usually added as inorganic phosphorus in the form of monocalcium phosphate (calcium dihydroxy-oxido-oxo-phosphorane). Unabsorbed phosphorus passes through into the manure, and if spread onto fields as a fertiliser can lead to excess phosphorus run-off into rivers and lakes leading to eutrophication. 

Fig. 3-2. I assume that 95 percent of the phosphorus supplied to the surface sea is incorporated into organic matter and returned to the deep sea in particulate form. One percent of the total survives to be buried in sediments. The rest is restored to the deep sea as dissolved phosphorus. The loss to sediments is balanced for the whole ocean by supply by the rivers. The fluxes here are in relative units.

The problem is to calculate the steady-state concentration of dissolved phosphate in the five oceanic reservoirs, assuming that 95 percent of all the phosphate carried into each surface reservoir is consumed by plankton and carried downward in particulate form into the underlying deep reservoir (Figure 3-2). The remaining 5 percent of the incoming phosphate is carried out of the surface reservoir still in solution. Nearly all of the phosphorus carried into the deep sea in particles is restored to dissolved form by consumer organisms. A small fraction—equal to 1 percent of the original flux of dissolved phosphate into the surface reservoir—escapes dissolution and is removed from the ocean into seafloor sediments. This permanent removal of phosphorus is balanced by a flux of dissolved phosphate in river water, with a concentration of 10 3 mole P/m3. 

Soley S (2010) Interaction between macrophytes and phytoplankton compartments for the uptake and decomposition of phosphorus compounds, the case of the Ebro river (NE Spain). Master thesis. University of Girona, Spain... 

In a general way, the overall movement of phosphorus on the continents can be considered as the constant water erosion of rock and transport of P in both particulate and dissolved forms with surface runoff to river channels and further to the oceans. The intermediate transformations are connected with uptake of P as a nutrient by... 

Aspila et al. [60] have described a semi-automated method for the determination of inorganic, organic and total phosphorus in river and lake sediments. Total phosphorus is extracted from sediments with 1M hydrochloric acid after ignition at a high temperature (550°C) (method 1) or by digestion with sulphuric acid-potassium persulphate at 135°C in a sealed PTFE-lined Parr bomb (method 2). 

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