Study On Methane Emissions Of Rice With Drip Irrigation Under Plastic Film

In this paper, aiming at the problem of methane emissions from drip irrigation rice in Ningxia Yellow River irrigation district, the Hongguangzhen Jinsha Village Farm of Helan County of Yinchuan City as experimental field.The experiment adopting the comparative method, systematically studied on the methane emissions of rice under different soil moisture, different fertilization amount and different irrigation technology.To provide a theoretical basis for that in Yellow River irrigation area. Experimental research shows that:(1)Under the condition of different soil moisture content, methane emission under film drip irrigation of rice was decreased with decreasing water content, The emission was first increasing then decreasing, the peak appeared in the daily 12:00; rice plants in different treatments have an unobvious gap; The diurnal variation of the temperature at 0.8m high over the rice showed increased first and then decreased; In a certain temperature range, the higher the temperature, the higher the efficiency of transfer of methane, methane emissions is greater.(2)Under the condition of different fertilization treatments, the methane emission of rice under drip irrigation film showed a downward trend after the first increase at lm high over the ground, and it was decreased along with the increased of fertilization, it showed that applying urea can effectively inhibit the methane emission from the rice. Rice photosynthesis were increased with the increased of fertilization amount; In the whole development process, amount of fertilizer on rice plants have an unobvious effect. Under the condition of different fertilizer amount, the relationship between different fertilizer rate and temperature was not significant. It was increased first and then decreased during the whole growth period, the maximum value appeared at the heading stage; Increase the amount of fertilizer can increase the yield of rice.(3)In the condition of different irrigation technology processing, the cultivation mode drip irrigation can significantly reduce emission of methane; Compared with sprinkler irrigation treatment, photosynthetic rate of drip irrigation treatment was 11.45% higher on average. And rice with drip irrigation under mulch film is more conducive to the growth of rice, and effectively restrain the methane emissions. The entire development process of rice,different irrigation has a little effect on rice plant height; Compared with sprinkler irrigation cultivation techniques, the temperature is 2.6℃(9.7%) higher on average at 0.8m high over the rice, rice production with drip irrigation under mulch is 44.75% higher on average in the whole growth period.