| This article researched the effects of combined application of chemical fertilizer and organicfertilizers like cow dung, fowl dung, biogas residue and straw on nitrogen in tobacco planting yellow soil undercondition of equal nitrogen and 20% organic nitrogen through field experiment of simpling with mash bags. Theresults showed that fertilizers had significant effect of slow releasing after applying. Soil total nitrogen content ofnon-straw treatment showed a tendency of high then low compared with straw treatment, but soil total nitrogencontent of only-straw treatment stayed on a low level during the whole period. Soil total nitrogen contents of organicfertilizer treatments increased by 0.01%-0.52% compared with purifying treatment. Soil nitrate and ammoniumnitrogen contents of organic fertilizer treatment were higher than purifying treatment from 0.26% to 33.95% in earlierstage. Soil ammonium nitrogen content of different treatments were 0.88%-25.97% higher than that of purifyingtreatment after 180 days. Soil nitrate nitrogen content of different treatments were 0.63%-25.37% higher than that ofthat of purifying treatment except fowl dung treatment, which was 3.41% lower than purifying treatment. The resultsalso showed that it was better than other treatments that combined application of animal manure and straw, it couldprovide long-effect high fertility for crops, which could last more than 40 days compared with purifying fertilizer. |
