| It has an important scientific value and productive meanning to studying the maize water consumption law and the distribution of water-nitrigen in farmland under film hole irrigation as the development of water-saving agriculture and the obvious problem of groundwater contamination. At present, home researchers have done a series of research on film hole irrigation, including infiltration characteristics, water movement characteristics on field surface, technic factors of irrigation and irrigation quality evaluation, but these studies did not deal with the distribution characteristics of field nitrogen and crop water consumption law. This thesis based on the related literature of film hole irrigation and nitrogen transport from the home and abroad, combined with the National Natural Science Fundation of China "Study on nitrogen transport characteristics and appraisal method on irrigation quality under film hole irrigation in fertilization farmland", this paper use the technical route included both outdoor experiment and theoretical analysis, and mainly on the experiment, study the water-nitrogen distribution characteristics and water consumption law under film hole irrigation in maize field. The main research results are as follow:(1) Study on the distribution characteristics of farmland water-nitrogen of different irrigation schedule. The results shown that the water and nitrogen seasonal changes obliviously in 0～60cm soil layers, and in each growing period, the nitrate nitrogen has a concentrated distribution area in soil profile, and the concentration peak reduced with the increasing of horizontal distance away from film hole center. The effects of irrigation frequency and irrigation quota to soil profile nitrate nitrogen more obvious in near fertilization point than further. The greater of irrigation quota and irrigation frequency, the faster of nitrate nitrogen seasonal reduced and deeper the reduced depth, and the nitrate nitrogen cumulative amount larger in 80～100cm depth, the irrigation quota has a largger effect than irrigation frequency. Irrigation four times, irrigation quota 524.7m~3/hm~2 is the best irrigation treament in maize growing period.(2) Study on the water-nitrogen distribution and nitrogen transformation characteristics under film hole irrigation. Film hole irrigation has a very good characteristics of moisture preservation, slow down the soil moisture sharply change phenomenon of border irrigation by film-covered, and saving water about 20.0%. The film hole irrigation eliminate the effect of intensive evaporation of border irrigation to nitrogen transformation, urea transformation rate even and gentle, and completed in 20 days after fertilization. In film hole irrigation, the nitrate nitrogen mainly distribution near the film hole and relative uniformity in vertical soil profile. In border irrigation, the nitrate nitrogen distribution concentrated in vertical soil profile near fertilization point. Compared with border irrigaion, nitrate nitrogen leaching amount reduced 27.0% in film hole irrigation.(3) Study on water consumption law and water productive efficiency of maize under film hole irrigation. The water consumption amount increases with the irrigation quota and irrigation frequency, and the effect of irrigation frequency to water consumption amount mainly depend on the irrigation time, and it has a little effect compared with irrigation quota; In certain irrigation quota and frequency, the water consumption amount and water consumption intensity all have a linear functional relationship with irrigation amount and frequency; The cumulative water consumption amount and water consumption intensity separately has a logarithmic and quadratic function relationship with maize growing days; The maize yield and water productive efficiency has a quadratic function relationship with water consumption amount. Compared with border irrigaion, productive efficiency of water promote 23.3%, increasing yield 15.9% in film hole irrigation.(4) Study on maize irrigation schedule under film hole irrigation manner. The effect of irrigation quota and frequency to maize biological index has an obvious influence in low irrigation quota and few irrigation frequencies. Increasing irrigation in seeding period has a big influence to maize height and stem diameter, decreasing the resistance lodging ability. The maize height has a quadratic function with cumulative water consumption in earing period; By calculation, obtain the irrigation quota (2111.973m~3/hm~2) in high water use efficiency; By experiment obtain the optimal irrigation schedule: total irrigation quota, 2098.95 m~3/hm~2, irrigation frequency, four times, irrigation two times in jointing period, one time in earing period, one time in filling period, and irrigation quota, 524.7m~3/hm~2 .
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