Biosolids are product of waste water or municipal solid waste collected through sewerage treatment, the processes of obtaining the biosolids involves various treatment processes which include digestion, thermal stabilization, thickening, dewatering and drying in order to obtain a free pathogen granules. These processes undergone by wastewater in the treatment plant ultimately clean the wastewater and remove the solids which are further treated to an acceptable standard for beneficial soil amendments. The application of biosolids are considered to improve soil organic matter, moisture content and provided essential nutrients such as nitrogen and phosphorus in arable land as potential plant nutrients supplements for crop optimum yield. Incubation studies on the biosolids amended soil have shown significant increases of soil phosphorus content being released as plant available P in the soil and therefore could be a good source of phosphorus in a deficient native phosphorus soils. Field scale experiments on wheat grown with sewage sludge have also shown yield production comparable to mineral fertiliser treated soils. This review is thereby aimed at explaining the concept behind the mineralisation and mobilization of biosolids phosphorus in soil. In this review paper an overview of the method of preparation, origin and sources, its application in agriculture and the environment, chemical composition, the environmental risk, soil amendments potentials of the biosolid sand regulatory and global perspective of sewage sludge disposal all are reviewed. From the review it was concluded that mineralisation and mobilization of biosolids phosphorus in soil have beneficial beniefits to both environment and soil nutrient amendment. It is thereby recommended that more researches should be carried out on the mineralisation and mobilization of other essential element such as nitrogen and biochar, although more research should be done with respect to mineralisation and mobilization of biosolids phosphorus in soil.
Key words: Phosphorus fraction, Biochar, Slude Pyrolysis, Agricultural lands, Nitrogen
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