Phosphorus freshwater

Examination of the influence of agriculture on phosphorus input to freshwater requires careful study to determine the most appropriate control strategies. The influence will vary in relation to whether the phosphorus is dissolved or particulate. Also, we know that variation in the input of particulate and dissolved... 

What are sources of nitrogen and phosphorus pollution in Earth s freshwater ... 

Disturbance of Phosphorus Biogeochemical Cycle in Agrolandscapes Conceptual ideas behind simulation of P cycling are related to construction of models for freshwater terrestrial ecosystems and a generalized oceanic system and understanding the restrictions of its application. 

The potential for N deposition to contribute to the eutrophication of freshwater lakes is probably quite limited. Eutrophication by atmospheric inputs of N is a concern only in lakes that are chronically N-limited. This condition occurs in some lakes that receive substantial inputs of anthropogenic P and in many lakes where both P and N are found in low concentrations (e.g., Table III). In the former case the primary dysfunction of the lakes is an excess supply of P, and controlling N deposition would be an ineffective method of water-quality improvement. In the latter case the potential for eutrophication by N addition (e.g., from deposition) is limited by low P concentrations additions of N to these systems would soon lead to N-sufficient, and phosphorus-deficient, conditions. The results of the NSWS shown in Table III, for example, can be used to calculate the increase in N concentration that would be required to push N-limited lakes into P limitation (assuming total P concentrations do not change). An increase of only... 

Currie, D., and J. Kalff. 1984. The relative importance of phytoplankton and bacterioplankton in phosphorus uptake in freshwater. Limnology and Oceanography 29 298-310. 

De Haan, H., and T. de Boer. 1986. Geochemical aspects of aqueous iron, phosphorus and dissolved organic carbon in the humic Lake Tjeukemeer, the Netherlands. Freshwater Biology 16 661—672. 

Jones, R. I., K. Salonen, and H. De Haan. 1988. Phosphorus transformations in the epilimnion of humic lakes Abiotic interactions between dissolved humic materials and phosphate. Freshwater Biology 19 357-369. 

Howarth, R. W., and S. G. Fisher. 1976. Carbon, nitrogen, and phosphorus dynamics during leaf decay in nutrient-enriched stream microecosystems. Freshwater Biology 6 221-228. 

Caraco, N.F., Cole, J.J., and Likens, G.E. (1990) A comparison of phosphorus immobilization in sediments of freshwater and coastal marine systems. Biogeochemistry 9, 277-290. 

Lijklema, L. (1977) The role of iron in the exchange of phosphorus between water and sediments. In Interactions Between Sediments and Freshwater (Golterman, H.L., ed.), pp. 313-317, Dr. W. Junk B.V., The Hague. 

Ramirez, A., Pringle, C. M. Molina, L. (2003). Effects of stream phosphorus levels on microbial respiration. Freshwater Biology, 48, 88-97. 

Andersen, T., and Hessen, D. O. (1991). Carbon, nitrogen, and phosphorus content of freshwater zooplankton. Limnol. Oceanogr. 36(4), 807—814. 

According to the latest estimates of Skinner [18], elements potentially recoverable from seawater are sodium, potassium, magnesium, calcium, strontium, chlorine, bromine, boron, and phosphorus because of their practically unlimited presence in the ocean. After improving respective technologies, recovery of the following elements is expected to become profitable as well lithium, rubidium, uranium, vanadium, and molybdenum. Additional profit can be gained since desalinated water will probably be obtained as a by-product. This could be important for countries with a very limited number of freshwater sources (e.g., Israel, Saudi Arabia). 

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