Phosphorus-32 movement water

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... 

Human activity has an enormous influence on the global cycling of nutrients, especially on the movement of nutrients to estuaries and other coastal waters. For phosphorus, global fluxes are dominated by the essentially one way flow of phosphorus carried in eroded materials and wastewater from the land to the oceans, where it is ultimately buried in ocean sediments. The size of this flux is currently estimated at 22 x 106 tons per year. Prior to increased human agricultural and industrial activity,... 

For no-water-flow conditions—that is, when net movement of the soil solution is considered negligible—mathematical equations that simultaneously describe rates of phosphorus transfer between A, B, C, and D phases may be given as follows (Mansell et al., 1977a) ... 

A detailed examination of phosphate distribution between solution and solid phase during calcite crystallization in a simulated natural water shows that phosphorus adsorbs as a mono-layer, causing slight changes in the solution phosphorus concentration. It appears that under the conditions examined in this study, calcite- mediated phosphorus mineralization has a role in the movement of phosphorus from the water column to bed sediments, although the extent and rates of the process in natural systems remain to be determined. 

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 nutrientby biota and interactions between river waters and bottom sediments. The majority (up to 90%) of eroded P remains trapped in the mineral lattices of the particulate matter and will reach the estuaries and ocean without entering the biological cycle. The smallest soluble part of eroded phosphorus is readily available to enter the biological cycle (Figure 28). 

Example Problem Suppose that a deep and fairly homogeneous soil is going to be used to dispose of septic tank waste water that contains 10 mg/liter of soluble phosphorus in the form of phosphate. A sorption isotherm is measured for the soil, from which the sorption capacity of the soil is estimated at Qm = 200 mg P/kg soil. The 600 liters of waste water that is generated each day is evenly disposed of over a 70 square meter area. Estimate the depth of phosphate movement in the soil after ten years, and make a decision whether a shallow well (10 meters deep) at the edge of the disposal area could become contaminated by phosphate. 

Adsorption It refers to the movement of soluble inorganic phosphorus from soil pore water to soil mineral surfaces, where it accumulates without penetrating the structure (Figure 9.16). Phosphorus adsorption capacity of soil increases with clay content or minerals. Adsorbed phosphorus maintains equilibrium with phosphorus in soil pore water. 

The cyclical movement of elements between living organisms (the biotic phase) and their nonliving (abiotic) surroundings (e.g. rocks, water, air). Examples of biogeochemical cycles are the carbon cycle, nitrogen cycle, oxygen cycle, phosphorus cycle, and sul-phur cycle. 

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