| Based on the worldwides literature review on film hole irrigation, considering the national science fund item'Nitrogen transport characteristics and quality evaluation of film hole infiltration with fertilization', this research involves laboratory studies, theoretical analyses and with an emphasis on the laboratory tests, according to the irrigation and fertilization character in China. This dissertation covers main researches on nitrogen transport and transform characteristics under film hole infiltration with fertilization single line and multi-line interference infiltration; temperature effect, the water consumption law and water utilization efficiency of corn; and the simulation of nitrogen transport and transform for soil water, heat and fertilization free infiltration. The main findings are as follows:(1) Through the indoor experiment for film hole infiltration with fertilization single line interference infiltration, the research of nitrogen transport and transform characteristics in wetten soil volume under film hole single line interference infiltration were done. Based on the laws for soil water distribution and nitrogen transfort and transform of film hole single line interference infiltration, the non-linear relationships of concentration of fertilization and time with soil moisture, soil NO(?)-N and soil NH4+-N were established for the wetting soil volume. The correlation coefficient of the equations were all more than 0.9200, the correlation were well, so the equation could inflect the effect of concentration of fertilization on soil water distribution and nitrogen transport and transform.(2) Through the indoor experiment, the research of the three processes of free infiltration, single line and multi-line interference infiltration; the characteristic of nitrogen transport and transform of multi-line interference infiltration were done. Based on the law for soil water distribution and nitrogen transfort and transform of multi-line interference infiltration, the non-linear relationships of concentration of fertilization and time with soil moisture, soil NO(?)-N and soil NH4+f-N were established for the wetting soil volume.. The correlation coefficient of the equations were all more than 0.9200, the correlation were well, so the equation could inflect the effect of concentration of fertilization on soil water distribution and nitrogen transport and transform of multi-line interference infiltration.(3) Through the indoor experiment, the transport and transform law of nitrogen according to the growth stages were researched under different irrigation quato, irrigation numbers, basic fertilizer quato and additional fertilizer quato. In the same growth stage but different irrigation quato and number, soil water and soil NH4+-N first increased and then decreased; soil NO(?)-N first increased and then decreased along with the soil depth. In the same growth stage but different basic fertilizer quato and additional fertilizer quato, soil NH4+-N first increased and then decreased along with the soil depth increase in heading and filling growth stages when with out basic fertilizer.Soil NH4+-N first increased and then decreased along with the soil depth increase in seedling and jointing stages when with out additional fertilizer.(4) According to the field experiment, the effect of irrigation quato and additional fertilizer quato to nitrogen transport and transform in all growth stages for corn were studied. The non-linear equations of time and the soil moisture, soil NO(?)-N, and soil NH4+-N were established, the equations of irrigation quato and those variables, the equation of additional fertilizer quato and those variables were also established. The correlation coefficients of the equations were all more than 0.9200, the correlation were well. The sine and cosine functions of soil water and time were put forward for all the growth stages under different irrigation quato. The non-linear functions of soil NO(?)-N and time and soil NH4+-N and time were also put forward for different irrigation quato and additional fertilizer quato. The correlation were well and the standard errors were small, so the equation could inflect the law of soil water distribution and nitrogen transport and transform for corn under film hole irrigation.(5) The soil temperature changes of day, all growth stages, and along with the soil vertical section were researched for corn under film hole irrigation. The soil temperature-change of day was a sine and cosine function for film hole irrigation and check irrigation, the function of soil temperature and growth stage was also put forward. In the same depth, the maximum of soil temperature happened at 16:00 and the minimum happened at the next day 2:00 for film hole irrigation, but 14:00 and the next day 2:00 respectively for check irrigation. For film hole irrigation and check irrigation, the soil temperature decreased along with the soil depth of 0-40.0cm and maintained stably within 40.0-80.0cm. The average value of soil temperature contrast was 1.09℃within the depth of 0-80.0cm for all growth stages for film hole irrigation and check irrigation.(6) The water consumption law and water utilization efficiency were researched under different irrigation quato and numbers for corn film hole irrigation and check irrigation. The water consumption model was established based on the SPAC system. The water consumption first increased and then decreased along with the growth stage increasing, showing the change of parabola curve. The water consumption increased along with the irrigation quato and time increasing. For the check irrigation, the total water consumption of all growth stage were 54.72%, 44.19% and 36.42% higher than film hole irrigation for irrigation numbers of 3,4 and 5 respectively. For the film hole irrigation, the water utilization efficiency first increased and then decreased along with the irrigation quato and number, when the irrigation number was 4 and the irrigation quato was 450.0m3/hm2, the water utilization efficiency got the maximum value 2.28 kg/m3. The reasonable irrigation program is that the irrigation quato is 450.0m3/hm2, irrigation number is 4, basic fertilizer quato is 150.0kg/hm2 and additional fertilizer quato is 300.0kg/hm2.(7) The equations for soil water and heat transport and the equations for soil water and nitrogen transport and transform were used to simulate the soil water and heat transport and soil water and nitrogen transport and transform under solution free infiltration for corn film hole irrigation. The calculating values of soil water and temperature fitted well with the measured value, the correlation coefficient of soil water was bigger than 0.91 and that of the temperature is bigger than 0.90. The soil water increased within the depth of 0-40.0cm, but decreased in 40.0-100.0cm; the temperature decreased in 0-40.0cm and maintained stable state below 40.0cm. In the process of soil water and nitrogen transport and transform under solution free infiltration, the root mean square errors between soil water calculating value and the measured value were 0.5910 and 0.5349 respectively for infiltrating time of 120.0min and 10 day; the root mean square errors between soil NO(?)-N and NH4+-N calculating value and the measured value were 0.4388 and 0.7299,0.8431 and 0.8975 respectively for infiltrating time of 5 day and 10 day; they fitted well.
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