Effects Of Nitrogen Fertilizer Type,Straw Residue And Irrigation On Paddy Ammonia Volatilization And Greenhouse Gas Emissions

The research was carried on in large-scale percolation pond in the College of Agriculture YangZhou university in 2014-2015,under rice-wheat rotation,with Wu breeding japonica 27,research the effects of different soil types,nitrogen fertilizer type,straw returned and water management on paddy fertilizer ammonia volatilization,ammonium nitrogen?NH₄⁺-N?concentration,greenhouse gas emission intensity?CH₄?CO₂?N₂O?,nitrogen absorption efficiency,nitrogen accumulation,yield and yield components of rice field,designed to filter out eco-friendly soil cultivation mode,to guide and improve the utilization efficiency of nitrogen fertilization of paddy fields,reduce greenhouse gas emissions and provide theoretical basis for the ecological environment.The main results are as follows:1?The main form of nitrogen in surface water after fertilizer nitrogen application is N14+-N.After the second day,ammonium nitrogen concentration in water will rapidly rise.The concentration of NH₄⁺-N in surface water reaches the maximum in 2?3 days after fertilizer nitrogen,then gradually reduced.N4+-N average concentration of sandy soil in different treatment is 15.58mg·L^-1·d^-1,average concentration of clay soil is 12.98mg·L^-1·d^-1.Two types of soils,straw returned can not reduce the concentration of NH₄⁺-N obviously?P>0.05?.Water-saving irrigation significantly decreased average concentration of NH₄⁺-N after fertilization significantly?P<0.05?,decreased by 0.31?3.56 mg·L^-1·d^-1.Resin net control urea for one time significantly reduces the average concentration of ammonium nitrogen?P<0.05?,decreased by 0.07?5.72mg·L^-1·d^-1.The smallest treatment is not the treatment in straw,and with the resin net control urea and water saving measures,the biggest for the conventional water management.2.The average ammonia volatilization on sandy is 52.83 kg·hm^-2,on clay soil is 45.98kg·hm^-2.On the sandy soil,straw returned has not significantly influence,resin net control urea can save the application number and reduce amount of ammonia volatilization significantly?P<0.05?,the total amount of ammonia volatilization reduced by 3.21?13.61kg·hm^-2,water-saving irrigation significantly reduces the total amount of ammonia volatilization reduced by 5.21?14.27kg·hm^-2?P<0.05?.Straw returned has no significant influence?P>0.05?,type of nitrogenous fertilizer,irrigation have a significant effect on ammonia volatilization,also has a significant interaction between two measures?P<0.05?,application of both treatment,total ammonia volatilization loss reduce 32.43%.On the clay soil,straw returned significantly reduces the total amount of ammonia volatilization,reduced 1.61?2.74 kg·hm^-2,resin net control urea significantly reduces the total amount of ammonia volatilization?P<0.05?,reduced 3.42?7.24kg·hm^-2,water-saving irrigation significantly reduced the total amount of ammonia volatilization?P<0.05?,decreased 2.93?6.75kg·hm^-2.Straw returned has a significant effect on ammonia volatilization?P<0.05?;but the straw returned and types of nitrogenous fertilizer,irrigation,no significant interaction effect,the three measures also have no interaction effect?P>0.05?,type of nitrogenous fertilizer,irrigation has a significant effect on ammonia volatilization,also has a significant interaction between two measures?P<0.05?.Application of resin net urea and water saving irrigation,total ammonia volatilization loss reduce 23.08%compared with conventional treatment.3.In measuring three kinds of greenhouse gases of CH₄ and CO₂ and N₂O,the lowest proportion of the global warming potential?GWP?is N₂O,there is a big difference between CH₄ emission during whole growth period.Straw returned to paddy field increased emissions of CH₄ emission flux by 6.94?33.47 times,which caused the increase of emissions of greenhouse gases by 0.67?2.41 times.Resin control released urea and water-saving irrigation has significant effect to reduce emissions,which reduced by 11.77%,17.14%times.Compared to contrast treatment emissions,water management and nitrogen types,straw residue have interaction effects obviously?P<0.05?,Straw residue returned with applying resin net control urea and water-saving irrigation could reduce 50.19%times greenhouse compared to only Straw residue returned.4.The average rice yield is 9017.97 kg·hm^-2 on sandy soil,and 9113.15 kg·hm^-2 on clay soil.It will cut down the average rice yield significantly when apply the controlled release fertilizer for one-time,the average rice yield on sandy soil decreased by 2.11%?9.70%times,apparent utilization of nitrogen reduced by 4.51?14.21%,and agriculture utilization reduced 0.71?3.38kg·kg^-1,the average rice yield on clay soil decreased by 1.39%?4.81%timesapparent utilization of nitrogen reduced by 1.02?9.31%,and agriculture utilization reduced 0.46?1.66kg·kg^-1.There is no significant influence of straw returned on panicle number,grain number per panicle and yield in sandy soil,nitrogen apparent utilization and agriculture utilization?P>0.05?.But on the clay increase significantly?P<0.05?,yield increased by 1.15%?3.32%,nitrogen apparent utilization increased by 1.12?8.61%,agriculture utilization ratio increased by 0.39?1.09 kg kg^-1.Water-saving irrigation can increase panicle number and grain number per panicle significantly on sandy soil?P<0.05?,increased by 0.36%?2.39%,nitrogen apparent utilization increased by 0.70-3.98%,utilization rate of agriculture increased by 0.12?0.75kg·kg^-1,on clay soil increased by 0.77%?2.67%,nitrogen apparent utilization increased by 0.74?4.02%,agriculture utilization increased by 0.25?0.90kg kg^-1.