Effect of integrated management of irrigation regimes, chemical fertilizers and compost on some soil moisture extracted characteristics in paddy field

Quantification of fertilizers losses is important to ensure sustainability of soil fertility, surface and ground water resources and for the development of crop nutrient management. Due to evaluation the effect of organic and chemical fertilizers under different irrigation regimes on chemical properties of soil, a split plot experiment in a randomized complete block design with three replications was conducted at Rice Research Institute of Iran, during 2013 and 2014. Irrigation regimes were 1.3, 1 and 0.7 times of evaporation from evaporation pan as the main plot while six different kinds of fertilizers as the sub plots,C1= no fertilizer, C2=N60- P30- K60 kg.ha-1, C3= C2 compost (5 t.ha-1), C4= N60 kg.ha-1 compost (5 t.ha-1), C5= P30- K60 kg.ha-1) compost (5 t.ha-1), and C6= compost (5 t.ha-1). Soil water extractions were gathered in 15, 25 and 50 days after seedling (i.e. 4 to 5 days after urea fertilizer application) and measured their salinity, pH, total nitrogen and potassium. The results showed that despite the significant effects of treatments on measured properties, the amount of irrigation water will be saved 21.18 and 42.46 percent by changing the irrigation method from flooded to 1 and 0.7 of evaporation, respectively. Using compost instead of chemical fertilizers in the soil will be reduced 39.19 percent of total nitrogen and 48.15 percent of total potassium in the soil extraction. The results of this research indicated that using a combination of compost (5 t.ha-1) and nitrogen (60 kg.ha-1) together with irrigation regime of one times evaporation from pan can save water and protect the environment and at the same time also produced the highest yield.