作　　者： ; ; ; ; ; ; ;

机构地区： 华中农业大学植物科学技术学院作物生理与栽培研究中心

出　　处： 《农业环境科学学报》 2008年第4期1326-1334,共9页

摘　　要： 通过田间采样与室内分析相结合的方法,对华中地区稻鸭、稻鱼共作生态系统N素动态及平衡进行了系统研究。结果表明,对于各处理,主要的N输入来自施肥、降雨和灌溉水,其中降雨的N输入量为42.83kgN·hm-2,灌溉水N的输入量分别为34.36(CK)、32.72(RD)和41.72kgN·hm-(2RF)。主要的N损失包括N2O释放、NH3挥发、N淋失、鸭和鱼的收获及水稻吸N。CKN2O释放损失量为4.04kgN·hm-2,显著低于RD的4.31kgN·hm-2和高于RF的3.76kgN·hm-2,表明稻田养鸭能增加N2O释放损失而养鱼则降低N2O释放损失。RD和RFNH3挥发损失分别为43.09和44.89kgN·hm-2,低于CK,这与鸭和鱼的存在降低了田面水pH有关。CK、RD和RFN淋失量分别为6.73、6.11和5.81kgN·hm-2。因鸭和鱼收获而损失的N量分别为0.60和0.18kgN·hm-2。水稻N的吸收是稻田最主要的N损失,CK、RD和RFN吸收量分别为(219.95±20.61)、(273.65±53.49)和(279.22±17.47)kgN·hm-2。N平衡分析显示,施肥和水稻吸N是影响N平衡最主要的影响因素,而NH3挥发损失、降雨和灌溉水N的输入也是影响N平衡的重要因素;与CK相反,由于鸭和鱼的存在,RD和RF为N平衡为正,表明鸭和鱼的存在加速了土壤有机N营养的周转,从而显著提高了水稻N输出。 Field experiments on nitrogen dynamics and cycling in integrated rice-duck and rice-fish ecosystems in subtropical region of China were conducted from May to September in 2007. The experiment field was equally divided into nine plots for three different treatments ： （ 1 ）conventional rice field （ CK ）, （ 2 ）integrated rice -duck ecosystem （ RD ） and （ 3 ）rice -fish ecosystem （RF）. The N input from precipitation was 42.83 kg N·hm^-2. The N input from irrigation water in CK, RD and RF were estimated to be 34.36, 32.72 and 41.72 kg N·hm^-2, respectively. N losses via N2O emission in CK, RD and RF were 4.04, 4.31 and 3.76 kg N·hm^-2, respectively, which showed that compared with CK, RD enhanced N losses via N2O emission while RF decreased N losses via N2O emission. N losses via NH3 volatilization in RD and RF were 43.09 and 44.89 kg N ·hm^-2, respectively, lower than 46.30 kg N·hm^-2 in CK. This was because the presence of ducks and fish resulted in marked decrease in floodwater pH. N outputs via leaching in CK, RD and RF were 6.73, 6.11 and 5.81 kg N·hm^-2, respectively. N outputs via ducks and fish removal were 0.60 and 0.18 kg N·hm^-2, respectively. N uptake by rice was the major N output and was（219.95±20.61 ）,（273.65± 53.49）and （279.22±17.47）kg N·hm^-2 in CK, RD and RF, respectively. The N balance analysis showed that fertilization and N uptake of rice were the main factors to affect N balance while N output via NH3 volatilization and N input from precipitation and irrigation were also significant. Moreover, due to the presence of ducks and fish, the apparent N balance in RD and RF was positive in contrast to CK, suggesting that the presence of ducks and fish accelerated the turnover of soil organically bound nutrients and thus significantly increased N output via rice uptake.

关 键 词： 稻鸭 稻鱼生态系统 灌溉水 淋失 平衡 挥发 释放

领　　域： [环境科学与工程]