effects of long-term municipal waste compost application on the concentrations of macro elements and yield of rice

an experiment was conducted as randomized complete block design with three replications and 14 fertilizer treatments in year 2014. the treatments were including the control, application of chemical fertilizers according the soil analysis, application of 15, 30 and 45 tons of municipal  waste compost per ha as simple and with 25, 50 and 75% of chemical fertilizers. the results revealed that the 7 years using of municipal waste compost significantly increased the concentrations of nitrogen, phosphorus and potassium of the soils and rice grains and it improved the yield of rice as well. the highest concentrations of macro-nutrients (nitrogen, phosphorus and potassium) were obtained in the treatment of 45 t/ha of municipal waste compost + 75% chemical fertilizers. the concentrations of nitrogen, phosphorus and potassium were increased 73.68, 230.0 and 30.74%, respectively, compared to the control treatment. treatment of 45 t/ha + 25% of chemical fertilizer had the highest 1000 grains weight. the percentage of 1000 grains weight was increased 9.82 compared to the control treatment. the highest yield of pad was obtained by using of 45 tons + 25% of chemical fertilizers that compared to the control treatment showed 51.33% increase. finally, from the results, it can be concluded that the combination of municipal waste compost and chemical fertilizers are reliable organic waste and fertilizers management strategy to increase the concentrations of macro-nutrients in rice and increase the rice yield as well.