不同水肥综合调控模式下水稻生长特征、水肥利用率及氮磷流失规律

Growth Characteristics of Rice,Water-fertilizer Utilization and Nitrogen and Phosphorus Loss Law Under Different Water-fertilizer Control Patterns

为进一步探明水稻生长与水分养分之间作用机制,充分发挥水肥耦合效应,在湖北省灌溉试验中心站开展了水肥综合调控模式试验研究。设置了常规淹灌模式(W0)、间歇灌溉模式(W1)、蓄雨型间歇灌溉模式(W2)3种灌溉模式;不施氮肥处理(N0)、当地实际施氮水平(N1)、当地施氮水平的75%(N2)3种施氮水平;基肥+一次追肥(F1)、基肥+二次追肥(F2)2种施肥方式。结果表明,与淹灌相比,间歇灌溉有利于水稻后期生长及高产,总氮排放负荷减少26%、总磷减少11%,氮肥利用率提高5.2%;与间歇灌溉相比,蓄雨型间歇灌溉会促进水稻全生育期生长,但后期茎叶过盛使产量略有减少,总氮排放负荷减少29%、总磷减少39%,氮肥利用率相当;在一定范围内增加施氮量可促进水稻的生长发育与高产;高施氮量下增加追肥次数可促进水稻后期生长与高产,但低施氮量下增加追肥次数可能会产生相反效果。

In order to further explore the mechanism between rice growth and water nutrients,give full play to the coupling effect of water and fertilizer,the experimental study on the comprehensive regulation of water and fertilizer was carried out at Hubei Provincial Central Station.Three irrigation modes were set up:conventional flooding irrigation mode(W0),intermittent irrigation mode(W1),and rain-storing intermittent irrigation mode(W2),as well as three levels of nitrogen application:no nitrogen fertilizer treatment(N0),local actual nitrogen level(N1),local application nitrogen level 75%(N2);There are two kinds of fertilization methods:base fertilizer+primary topdressing(F1),base fertilizer+secondary topdressing(F2).The test results show that compared with flooding irrigation mode(W0),intermittent irrigation mode is beneficial to the late growth and high yield of rice,the total nitrogen emission load is reduced by 26%,the total phosphorus is reduced by 11%,and the utilization rate of nitrogen fertilizer is increased by 5.2%;Compared with intermittent irrigation mode,rain-storing intermittent irrigation mode will promote the growth of rice during the whole growth period,but in the later stage,excessive stems and leaves will slightly reduce the yield,total nitrogen emission load decreased 29%,total phosphorus decreased 39%,and the nitrogen fertilizer utilization rate is equivalent;Increasing the amount of nitrogen in a certain range can promote the growth and high yield of rice;And increasing the number of topdressing under high nitrogen can promote the late growth and high yield of rice,but increasing the number of topdressing under low nitrogen may have the opposite effect.