Effects of Long-term Different Fertilization on the Nitrogen Distribution in Manural Loessial Soil

This study had evaluated the effects of long-term different fertilizer treatments including organic manure, chemical fertilizer, and their combinations on accumulation and movement of NO-3-N and alkali-hydrolyzable N in Manural Lessial Soil under wheat-corn rotation system. The different fertilizer treatments increased the contents of alkali-hydrolyzable nitrogen and nitrate nitrogen in the soil, especially the available nitrogen in plow layer. The addition of manure had more significant positive effect on alkali-hydrolyzable N in the soil; and the application of chemical fertilizer had more signficant role in increasing soil NO-3-N. Compared to the contro(lwithout addition of fertilizer), the addition of manure decreased the accumulation and leaching of NO-3-N in soil profile. The contents of soil nitrogen in fall was higher than that in summer in the same year. The application of low rate of manure or combining with low rates of chemical fertilizer(M150 t·hm-2 , N150 kg·hm-2 , P 60 kg·hm-2)was the effective way to control accumulation of NO-3-N in soil profiles and leaching loss.