ABSTRACT
Application of large amount of nitrogen fertilizer, has been reported to decrease soil pH, nitrate leaches into the groundwater, surface runoff water from the field transports phosphorus, ammonia and nitrate to water reservoirs and rivers. During the different industrial and production procedures and probably during everyday use some by-products and wastes are generated which have high micro- and macro element content and they do not endanger the environment. They should not be handled as wastes but rather as nutrient amendments and use in the plant nutrition with the reduction of chemical fertilizers. We have come to the conclusion that all of the examined by-products can be used in the plant nutrition but it is essential to determine the concentrations of application accurately for field use.
