| Based on the related literature about film hole irrigation and nitrogen transport from the home and abroad and combined with the National Natural Science Fundation of China, this paper uses the technical route including both experiment and theoretical analysis, and studies the nitrogen transformation, transport and distribution characteristics and temperature effect under film hole irrigation. The main research results are as follows:(1) Studies the characteristic of film hole free infiltration, film hole unilateral interference infiltration and film hole bilateral interference infiltration and establishes the mathematic model of film hole single source free infiltration based on one-dimension vertical infiltration volume and side infiltration volume, film hole unilateral interference infiltration and film hole bilateral interference infiltration model based on induction volume and interference interface area; Studies the law of water flow advance and regression processes, and puts forward a method to determine single point source infiltration parameters based on Kostiakov model with data in film hole irrigation. Field infiltration parameters in film hole irrigation.(2) Based on the indoor experiment, the paper studies the transport and transformation rule of urea, and opens out the effect of different fertilizer application pattern, different fertilizer amount and different water mount on urea transformation characteristic. The urea transport rate in the vertical direction is more than in the horizontal direction and all of them decrease with the transport distance. The urea transport consists with water transport. To the film hole free infiltration, the ammonium mainly exits near film hole. The ammonium firstly increases and subsequently decreases with time. The nitric nitrogen increases with time and decreases with the distance being away from film hole. Different fertilizer application pattern has a great effect to ammonium nitrogen distribution, and the distribution law is the same as urea distribution after infiltration with different fertilizer application pattern. Different fertilizer application pattern has a little effect to nitric nitrogen distribution. Nitrification is feeble during the former time, and is strength after 7 days for transformation. Nitric nitrogen content is high near the film hole and is more in the horizontal direction than in vertical direction. As fertilizer amount and water amount increasing, the distribution scope and content of ammonium nitrogen and nitric nitrogen content increases, but water amount increment does not distinctly increase ammonium nitrogen content because of ammonium volatilization.(3) Studies the urea transformation characteristic of farmland under film hole irrigation and opens out the effect of fertilizer amount and water amount on urea transformation characteristic. Urea transform completely after the 15th day. During the course of urea transformation, the urea amount decreases, the ammonium nitrogen amount firstly increases and subsequently decreases, and nitric nitrogen gradually increases. Sets up the power function between soil nitric nitrogen content and transformation time. Comparing with board irrigation, film hole irrigation accelerates the speed of urea transform and increases the distribution scope and amount of nitric nitrogen. The increment of fertilizer amount and water amount hastens the urea transformation and increases the nitric nitrogen amount and distribution scope, so big plant space does. Sets up the power function between soil nitric nitrogen content and fertilizer amount and water amount.(4) Studies the nitric nitrogen dynamic change and distribution characteristic under film hole irrigation with maize absorbing nitrogen for the first time. The nitric nitrogen heap peak of film hole irrigation is obviously wider than board irrigation during the three-leaves period and is lower after three-leaves period. Nitric nitrogen leach does not happen under board irrigation in the whole growing period, but happens in the elongation period and jointing period under film hole irrigation. The more the fertilizer is, the more nitric nitrogen content is. The fertilizer increment postpones the biggest period of nitrogen absorbing, but increases the leach amount and the rudiment. The more water amount is, the lower nitric nitrogen heap peak is, and the more the nitric nitrogen leach amount is in the elongation period and jointing period. The distance being away form film hole has effect on the leaching period of nitric nitrogen. The little the distance is, the longer the leaching period in the soil profile is. Big plant space hastens the nitric nitrogen moving down, increases the nitric nitrogen amount and promotes the danger of nitric nitrogen leach. Sets up the power function between biological index and yield index and total waterconsumption amount.(5) Studies on maize water consumption rule, water productive efficiency and so on and opens out the effect of fertilizer amount and water amount on them. Jointing period is the key period of maize water consumption under film hole irrigation and board irrigation. In the same period, the water consumption in the every growing period under board irrigation is bigger than under film hole irrigation. the water productive efficiency of board irrigation is little than film hole irrigation. With fertilizer amount and water amount increasing, the total water consumption and yield increases, but the water productive efficiency decreases. Sets up the quadratic function between water consumption amount of every growing period and maize growing days. Sets up the power function between total maize water consumption and fertilizer amount and water amount. Except of spike height, every biologic index and yield index of board irrigation is little than film hole irrigation, so film hole irrigation has obviously yield increase effect comparing board irrigation. The more water amount and fertilizer amount is, the more every biologic index and yield index is. The power function exits between every biologic index and yield index and total water consumption.(6) Studies the soil temperature effect and opens out the characteristic of daily change and seasonal change of soil temperature under film hole irrigation. Daily change of soil temperature under film hole irrigation is more smooth than board irrigation. The temperature increment effect decreases with the soil layer depth increasing. The linear function exits between soil temperature of film hole irrigation and soil temperature of board irrigation. The quadratic function exits between the lower soil layer and surface layer. Seasonal change of soil temperature under film hole irrigation is large during the former period, and is little during the latter period. The temperature increment effect in the season decreases with the soil layer depth increasing. Soil water content in the interplant is larger than in the interrow, so soil temperature in the interplant rises and falls slowly than in the interrow. Soil temperature difference between profiles in the interplant is smaller than in the interrow.These results provide theoretic proof for developing farmland fertilizer application and appraising the effect of nitric nitrogen on environment under film hole irrigation.
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