Study On The Effect Of Fertilizing Management On Nitrogen Transition In Phaiozems

The paper studied the rules of functional bacteria diversification(self-nitrogen-fixation bacteria,ammonifying bacteria,nitrobacteria,denitrobacteria ) on the nitrogen transitions and soil enzyme transformation(urease,catalase) under the different fertilizer managements in agro-ecosystem of the black soil district in Songnen Plain and effects on the intensity of the spontaneous nitrogen fixation,the intensity of the process of ammonification,nitrification and denitrification in soils in order to further study the mechanism of nitrogen transition in soils,supply scientific basis on reasonable use of the nitrogen in soil and guidance for the nitrogenous fertilizer utilization in field practice and provide scientific reference for protecting black soil resource, reducing agricultural non-point pollution and producing the organic food.Main conclusions educed from this experiment were as follows:1.The effect of different fertilizing treatments on soil ammonifying bacteria,nitrobacteria, denitrobacteria was significant.The impact of separate fertilizer on ammonifying bacteria was not remarkable,but it could improve the growth of denitrobacteria.The manure application could improve the quantities of soil ammonifying bacteria,nitrobacteria and denitrobacteria.2.In the whole growing period,the effect of different fertilizing treatments on the soil ammonification intensity,the nitrification intensity and denitrification intensity was significant.The separate manure and fertilizer application and combining of manure and fertilizer could improve soil ammonification intensity,whereas the fertilizing application could decrease soil ammonification intensity.The separate manure and fertilizer application and combining of manure and fertilizer treatments play the role in promoting nitrification intensity.3.The separate manure and fertilizer application and combining of manure and fertilizer treatments could improve the soil urease activity and catalase activity.However,the impact on soil enzyme was different among them;the effect of manure application is higher than that of fertilizer on improving the soil caralase activity.4.Soil pH value,soil water content had definite impacts on the soil bacterium related with soil nitrogen transformation and biochemical intensity respectively.The higher pH value facilitated the growth of ammonifying bacterial,whereas restrained the quantities of denitrobacterial.5.NO₃^--N leaching under different treatments of manure and fertilizer application were significantly higher than that of comparison and had obvious differences.To compare with comparison,the rate of NO₃^--N leaching in the treatment of fertilizers was higher than the treatment of manure.Under the condition of equal amount of nitrogen,the rate of leaching loss in the treatment of manure was less than the treatment of fertilizers,whereas the loss of nitrogen in the treatment of nitrogen was more than the treatment of manure.6.The content of NO₃^--N in soil was relative directly to the content of NO₃^--N leaching.The rate of NO₃^--N leaching was increased with the content of NO₃^—N in soil.The relative coefficient was r = 0.726 with the content of NO₃^—N under 30cm depth in soil and Nitrate Leaching.The relative coefficient was r = 0.836^**with the content of NO₃^—N under 60cm depth in soil and Nitrate Leaching.We can draw that with the compare to comparison the different treatments of manure and fertilizer can increase the rate of nitrogen leaching in soil.The leaching under the fertilizer application treatment was the most and the rate of loss was maximal,whereas the treatments of mamure application and the treatments of mix mamure and fertilizer application can reduce effectively the loss of nitrogen.7.All of Manure and fertilizer applications increased the content of nitrogen in soybean plant, which was significantly increased under high fertilizer application,and in the next place was under low farming fertilizer application and the high manure,and again was under half of manure and half of fertilizer application,and was the lowest under low manure application.From it we can draw the conclusion the fertilizer application can increase the content of nigrogen in plant.8.Soil ecosystem with no fertilizers was an exhausted ecosystem,the input of nitrogen came mainly from nitrogen-fixation in the atmosphere,therefore the intensity of the spontaneous nitrogen fixation under control application was higer than other fertilizer application effectively.