稻田总磷迁移规律与最佳灌排模式研究

Migration Rule of Total Phosphorus in Paddy Fields and Election of Optimal Irrigation and Drainage Mode

以超级稻为试验对象,采用随机试验设计,利用测桶试验,研究浅水勤灌、控制灌溉、浅湿调控、覆秸秆旱作灌排模式下地下排水及不同深度土壤渗漏液的总磷迁移规律。结果表明,与浅水勤灌和浅湿调控相比,控制灌溉和覆秸秆旱作显著降低了灌水量、灌水次数、地下排水量、总磷浓度和总磷流失负荷,有明显的节水省工减排效果。不同灌排模式地下排水总磷质量浓度波动下降,最大为0.450 mg/L;不同灌排模式、不同深度土壤渗漏液中,总磷浓度表现不同,除分蘖后期外均为表层最高,且随土壤剖面深度的增加而降低。浅湿调控和覆秸秆旱作的土壤渗漏液总磷浓度高于浅水勤灌和控制灌溉。控制灌溉、覆秸秆旱作两年灌溉水分生产率均显著高于浅湿调控、浅水勤灌。与浅水勤灌相比,控制灌溉显著增产10.45%,覆秸秆旱作显著减产14.69%。综合灌排水量、灌水次数、磷素流失负荷、产量和灌溉水分生产率,控制灌溉是节水、省工、减排、高产的最佳灌排模式。

Taking super rice as test material, the randomized block design method and barrel experiment were conducted to investigate the effects of four treatments with migration of total phosphorus (TP) in underground drainage and soil leakage loss risks and movement of phosphorus and rice yield. Four treatments were:frequent shallow irrigation (FSI), controlled irrigation (CI) wet-shallow irrigation (WSI) and drought planting with straw mulching (DPS). The results showed that compared with FSI and WSI, CI and DPS could significantly reduce irrigation amount and irrigation frequency, the concentration of TP in underground drainage and underground drainage, and effectively promote water saving and emission reduction. Under different irrigation and drainage modes, there were many fluctuations in the whole growth period, and the maximum concentration of TP in underground drainage was 0.450 mg/L. The TP concentration in soil seepage at different depths was different in different irrigation and drainage modes. Except for the late tillering period, the TP concentration was the highest on the surface and decreased with the increase of soil profile depth. The TP concentration of soil seepage in WSI and DPS was higher than that in FSI and CI. Compared with the FSI, the yield of CI was increased by 10.45% and the DPS was decreased by 14.69%. The productivity of irrigation water in two years of CI and DPS was significantly higher than that of WSI and FSI. Comprehensively considering the irrigation and drainage, irrigation frequency and phosphorus loss, yield and irrigation water productivity, CI was the best mode for water saving, labor saving, emission reduction and high yield.