Phosphorus surface waters

A recent review of research on phosphorus input to surface waters from agriculture highlights the variability of particulate and dissolved phosphorus contributions to catchments. The input varies with rainfall, fertilizer application rates, the history of the application of the fertilizer, land use, soil type, and between surface and sub-surface water. The balance struck between export of nutrients from the catchment and recipient-water productivity is the primary factor which controls its quality. 

The destiny of most biological material produced in lakes is the permanent sediment. The question is how often its components can be re-used in new biomass formation before it becomes eventually buried in the deep sediments. Interestingly, much of the flux of phosphorus is held in iron(lll) hydroxide matrices and its re-use depends upon reduction of the metal to the iron(ll) form. The released phosphate is indeed biologically available to the organisms which make contact with it, so the significance attributed to solution events is understandable. It is not clear, however, just how well this phosphorus is used, for it generally remains isolated from the production sites in surface waters. Moreover, subsequent oxidation of the iron causes re-precipitation of the iron(lll) hydroxide floes, simultaneously scavenging much of the free phosphate. Curiously, deep lakes show almost no tendency to recycle phosphorus, whereas shallow... 

The moles X/moles P in average plankton is given by a, and b is the surface water concentration in phosphorus free water (water stripped of nutrients). In the case of P itself the surface ocean concentration is close to zero, while the deep Pacific has a concentration of 2.5 pM. For N, the N/P ratio of plankton is 16 and the surface water concentration is 0 pM. The predicted deep sea nitrate is 40 pM. The ratio of (deep)/(surface) is greater than 10. For calcium the Ca/P of... 

Fig. 14-5 Typical distribution of P and temperature in a temperate lake in summer. Thermal stratification restricts exchange between surface and deep wafers. Phosphorus is depleted in the surface waters by the sinking of biologically produced particles.

Carpenter SR, Caraco NE, Correll DL, Howarth RW, Sharpley AN, Smith VH (1998) Nonpoint pollution of surface waters with phosphorus and nitrogen. Ecol Appl 8 559-568... 

Ecologically, copper is a trace element essential to many plants and animals. However, high levels of copper in soil can be directly toxic to certain soil microorganisms and can disrupt important microbial processes in soil, such as nitrogen and phosphorus cycling. Copper is typically found in the environment as a solid metal in soils and soil sediment in surface water. There is no evidence that biotransformation processes have a significant bearing on the fate and transport of copper in water. 

Sharpley AN, Chapra SC, Wedepohl R, Sims JT, Daniel TC, Reddy KR (1994) Managing agricultural phosphorus for protection of surface waters issues and options. J Environ Qual 23 437-451... 

The excessive amounts of nitrogen and phosphorus as well as heavy metals migrate with water fluxes and enter into surface waters. This is accompanied by eutrophication of surface water bodies. 

Surface Water, in estuarine water, the half-life of fenamiphos was 1.80 d (Lacorte et al, 1995). Chemical/Physical. Emits toxic fumes of phosphorus, nitrogen, and sulfur oxides when heated to decomposition (Lewis, 1990). 

Ground and surface water Nutrient use and balance Nitrate leaching Phosphorus Pesticides Pathogens... 

Nitrogen fixation counteracts denitrification losses of N from surface waters and is fundamental to replenishing fixed forms of N in all aquatic ecosystems. It is thought to be the main process responsible for maintaining surplus inorganic N in lakes and streams. It is therefore basic to the concept that primary production in most lakes and streams is limited by phosphorus (72). 

Yoshimura,T., Nishioka, J., Saito, H.,Takeda, S.,Tsuda, A., and Wells, M. (2007). Distributions of particulate and dissolved organic and inorganic phosphorus in North Pacific surface waters. Mar. Chem. 103,112-121. 

Elemental phosphorus is listed as a hazardous substance and the discharge in excess of 1 pound to surface water is in violation of section 311(b)(3) of the U.S. code of regulations (EPA 1992a). Solid waste containing elemental phosphorus is characterized as a hazardous waste when it passes the characteristic of reactivity stipulated in 40 CFR 261.23. If so characterized, the solid waste must be managed as a hazardous waste (EPA 1992b). 

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