3种水稻种植模式的减氮效应和经济性评估

为探讨不同种植模式对水稻田氮素污染流失的影响和经济效益差异，于2016年4—10月在盘锦市鼎翔米业幸福农场内布设试验样地，采用对比试验、费用效益分析、情景分析等方法，开展了常规种植、低化学品和有机生态3种水稻种植模式的减氮效应和经济性评估.结果表明:①3种模式中有机生态种植模式的农田排水总氮含量最低，为1.94 kg/hm2，低化学品种植模式次之，为3.67 kg/hm2，常规种植模式最高，为5.87 kg/hm2.②有机生态种植模式单位面积经济净现值及经济净现值率最高，分别为23 302.53元/hm2和1.13；低化学品种植模式次之，分别为15 310.42元/hm2和1.06；常规种植模式最低，分别为14 855.92元/hm2和0.93.③在水稻价格上浮5%时，有机生态种植模式的经济净现值和净现值率最高，分别为21 218.14元/hm2和0.86，分别比低化学品种植模式及常规种植模式高7 425.26元/hm2和0.07及7 972.01元/hm2和0.17.④在水稻价格下调5%时，有机生态种植模式的经济净现值和净现值率依然最高，分别为16 872.82元/hm2和0.68，分别比低化学品种植模式和常规种植模式高6 030.87元/hm2、0.06和6 715.17元/hm2、0.15.研究显示，有机生态种植模式的减氮效应和经济效益明显高于低化学品种植模式和常规种植模式. 

Economic Evaluation and Nitrogen Reduction Effects of Three Rice Planting Patterns

To understand the difference of nitrogen reduction effects and economy among different cropping patterns, experiments were conducted at Dingxiang rice farm in Panjin from April to October in 2016. Nitrogen reduction effects and economy of cropping patterns of conventional management (CM), organic management (OR) and low chemical management (LC) were evaluated by ways of comparative trial, cost benefits analysis and scenario analysis. The results showed that OR produced the lowest total nitrogen loss, which was 1.94 kg/hm², while the total nitrogen loss of LC was higher than OR, which was 3.67 kg/hm². The total nitrogen loss of CM was the highest, which was 5.87 kg/hm². Moreover, the economic net present value (ENPV) and economic net present value rate (ENPVR) of OR were the highest over the three different cropping patterns. The ENPV and ENPVR of OR were respectively 23,302.53 RMB/hm² and 1.13. While the ENPV and ENPVR of LC were lower than OR, which were respectively 15,310.42 RMB/hm² and 1.06. The ENPV and ENPVR of CM were the lowest, which were respectively 14,855.92 RMB/hm² and 0.93. When the price of rice rose by 5%, the ENPV and ENPVR of OR would be still the highest, which were respectively 21,218.14 RMB/hm² and 0.86. The ENPV of OR was 7,425.26 RMB/hm² and 7,972.01 RMB/hm² higher than ENPV of LC and CM. And the ENPVR of OR was 0.07 and 0.17 higher than ENPVR of LC and CM. When the price of rice declined by 5%, the ENPV and ENPVR of OR would be still the highest, which were respectively 16,872.82 RMB/hm² and 0.68. The ENPV of OR was 6,030.87 and 6,715.17 RMB/hm² higher than ENPV of LC and CM. And the ENPVR of OR is 0.06 and 0.15 higher than ENPVR of LC and CM. The study indicated that the nitrogen reduction effects and economic benefits of OR were higher than those of LC and CM.