When we think about what can be done to achieve a sustainable agriculture in the context of fertilizers, preventing groundwater leaching pops up to be one of the first issues. More than ever before fewer growers need to produce much more yield in order to feed the rapidly growing population of the world. Development of machinery for agriculture, new plants varieties and advanced fertilizers are all supporting the growers and improve yield efficiency.
When it comes for plant nutrition there are 3 main elements that the plant needs, Nitrogen (N), Phosphorus (P) and Potassium (K). N is the most challenging out of the three, because it can be applied as Ammonia, Urea, forms of Ammonium such as Ammonium Sulphate, and forms of Nitrate such as Potassium Nitrate (and even Ammonium Nitrate).
Due to the negative charge of the soil particles, and the chemical form of the Nitrogen fertilizers, Ammonia tied to the soil partials. Urea in the soil, within short time, is transforming in to Ammonium (tied to soil particles or consumed by roots) and then to Nitrate. Nitrate has a negative charge, therefore it does not tie to soil particles and also does not consumed by the plant's roots, but flushes down the soil towards ground water. Urea, when applied on top of the soil, begins to volatilize as ammonia, which is a notorious greenhouse gas.
P can also leach but very slowly, and yet at places where the farmers use to fertilize with no limits or direction, suffer from water stream contaminations.
Luckily we now have better fertilizers that provide us effective tools for controlling and eliminating Nitrogen leaching. Haifa MulticoteTM Agri, Polymer coated fertilizer is a Controlled Release Fertilizer (CRF) coated with thin layer of polymer. Water penetrates the coating and beings to dissolve the fertilizer granule. Osmotic pressure is been build inside the capsule and water with dissolved fertilizer begins to Diffuse out of the Capsule, while fresh water keeps entering the Capsule.