Review:
Livestock manures have a high percentage of soluble and absorbable phosphorus. In areas where livestock manures are produced in large quantities and these fertilizers are immediately added to the soil surface, if rainfall occurs, large amounts of soluble phosphorus enter the rivers and freshwater sources through surface runoff. The rest of the phosphorus in the manure It remains in the soil and can enter the flowing waters with the movement of soil particles and sediments. The presence of phosphorus in running water and freshwater resources has led to the growth of algae and aquatic plants, which not only destroys the water quality of freshwater and drinking water sources, but also causes the death of aquatic animals, so it is necessary in areas where fertilizers Livestock are produced and consumed in large quantities. The amount of soluble phosphorus in the fertilizer is reduced so that we can use these fertilizers on the farm without polluting the water sources. The presence of phosphorus in running water and freshwater resources has led to the growth of algae and aquatic plants, which not only destroys the water quality of freshwater and drinking water sources, but also causes the death of aquatic animals, so it is necessary in areas where fertilizers Livestock are produced and consumed in large quantities. The amount of soluble phosphorus in the fertilizer is reduced so that we can use these fertilizers on the farm without polluting the water sources. In this experiment, various additives are included: Aluminum sulfate, calcium sulfate, ferrous sulfate, zinc sulfate, copper sulfate were used and the elements of aluminum, calcium, iron, zinc and copper each in 6 levels including: 0 (control), 250, 500, 1000, 2000 and 4000 mg / kg of fertilizer were used. After adding these materials to the fertilizers, the treated samples were incubated in the dark for three months. Fertilizer samples were prepared from the pots every month and the amount of soluble phosphorus, pH and EC of the samples were measured. The results of this study showed that the use of different additives reduced soluble phosphorus in all four types of fertilizers and aluminum sulfate additive was superior to other additives in this regard. Due to the use of different additives in four types of fertilizers, the pH of all treatments decreased over time but their salinity increased.
