江西省水稻蓄雨间歇灌溉模式初探

【目的】探索水稻蓄雨间歇灌溉模式节水减排效益。【方法】以鄱阳湖区双季早晚稻为试验材料,采用大田和测坑试验,研究了水稻蓄雨间歇灌溉模式对灌溉定额、排水定额、降雨有效利用率、产量、稻田水分生产率,以及氮、磷排放量的影响,并与间歇灌溉和常规淹水灌溉试验进行了分析比较。【结果】与淹水灌溉、间歇灌溉相比,蓄雨间歇灌溉灌排水量、灌排次数明显减少。双季早晚稻年平均灌水量分别减少975m^3/hm^2和1251m^3/hm^2,年平均灌水次数分别减少8次和7.5次;年平均排水量分别减少729 m^3/hm^2和893 m^3/hm^2,年平均排水次数分别减少5.8次和3.1次;蓄雨间歇灌溉降雨有效利用率明显提高。早稻降雨利用率分别提高12.40%和9.14%,晚稻分别提高6.84%和6.42%;蓄雨间歇灌溉模式下,双季早晚稻总氮排放量年平均减排7.64 kg/hm^2和3.12 kg/hm^2,减排幅度34.93%和14.26%;双季早晚稻总磷排放量0.180kg/hm^2和0.095kg/hm^2,减排幅度37.25%和70.59%。【结论】蓄雨间歇灌溉模式具有明显的节水、减排和提高降雨有效利用率的效果,在我国南方多雨地区具有较强的推广应用空间。

Preliminary Research on Rain Storage and Intermittent Irrigation Mode of Jiangxi Province

The Rain Storage and Intermittent Irrigation Mode is mainly based on the water control standards of each batch growth period of rice intermittent irrigation mode, which is an irrigation mode that improve the utilization efficiency of rainwater resources through increasing the post-rain water storage depth of rice fields and extending the residence time of the rainwater in the paddy field.【Background】The hydrology and water resources in Jiangxi Province present several characteristics, such as heavy rainfall, low effective utilization of rainfall, and severe water and fertilizer loss. Therefore it is necessary to study and develop a set of water control standards which is conducive to rice growth in Jiangxi Province, and it is of great significance to improve the effective utilization of rainfall and reduce the loss of nitrogen and phosphorus nutrients in the paddy field. Whatmore, it not only can improve the effectiveness of water and fertilizer utilization, but also can achieve the purpose of saving water, increasing yield, and improving efficiency in rice fields.【Objective】The aim of this paper is to explore the effect of water saving and emission reduction in rice rain storage intermittent irrigation mode. 【Method】Taking the double-season early and late rice in Poyang Lake area as the experimental material, the combination of field and pit test was used to study the irrigation quota, drainage quota, effective rainfall utilization rate, yield quota, paddy water productivity, and the productivity and effects of nitrogen and phosphorus emissions, which also analyzed and compared with intermittent irrigation and conventional flood irrigation experiments.【Result】①The volume of irrigation and drainage and the times of irrigation and drainage were significantly reduced compared with flood irrigation mode and intermittent irrigation mode. The average annual irrigation amount of double-crop early and late rice reduced by 975 m^3/hm^2 and 1 251 m^3/hm^2 respectively. The annual average irrigation times reduced by 8 times and 7.5 times respectively The annual average displacement reduced by 729 m^3/hm^2 and 893 m^3/hm^2, respectively, and the annual average drainage times decreased by 5.8 times and 3.1 times. ②The effective utilization rate of rainfall had been improved significantly. The early rice rainfall utilization rate increased by 12.40% and 9.14%, respectively, and that of the late rice increased by 6.84% and 6.42% respectively. ③The secondary rain storage intermittent irrigation mode can significantly reduce the nitrogen and phosphorus emissions of rice fields, and the annual average total nitrogen emission of double-season rice. The emission reduction is 7.64 kg/hm^2 and 3.12 kg/hm^2, and the emission reduction is 34.93% and 14.26%. The total phosphorus emission in the double-season early and late rice is 0.180 kg/hm^2 and 0.095 kg/hm^2, and the emission reduction range is 37.25% and 70.59%.【Conclusion】Rain storage and intermittent irrigation mode has obvious effects on saving water, reducing emissions and improving the effective utilization of rainfall, which can improve the efficiency of rainwater resources, and has a strong space for promotion and application in south rainy areas.