化肥减量条件下不同施用方法对土壤养分有效性及水稻产量的影响

大田试验条件下,采用裂区试验研究了翻压紫云英后化肥减量施用条件下不同施肥方法对土壤养分有效性及水稻产量的影响。结果表明:翻压紫云英22500kg/hm2后,配施80%化肥,底肥:分蘖肥:穗肥=5:5:0,与习惯施肥方法相比,早稻和晚稻收获后土壤中有效氮分别平均增加5.6%和9.8%;而底肥:分蘖肥:穗肥=3:4:3更有利于提高有效K含量,分别平均增加8.9%和13.2%;配施60%化肥,按底肥:分蘖肥:穗肥=5:5:0施肥显著增加早稻收获后土壤中有效K含量,增幅为27.1%;肥料全部用作分蘖肥时降低晚稻或早稻收获后土壤有效N、K含量;配施60%～80%化肥,早稻和晚稻产量均以施肥方法底肥:分蘖肥:穗肥=0:7:3最佳。

Effects of Different Fertilization Methods on Availability of Soil Nutrient and Rice Yield under Reducing Application Rate of Mineral Fertilizer

A field experiment was carried out to study the effects of different fertilization methods on the availability of soil nutrient and rice yield under the condition of reducing the application rate of mineral fertilizer.The results showed that under the condition of the combined application of 80% chemical fertilizer and 22500 kg/hm2 green manure(Astragalus sinicus),in comparison with the customary fertilization method,the fertilization method which basal fertilizer:tillering stage dressing:panicle fertilizer was 5:5:0 could increase the content of available N in the soil after the harvest of early rice and late rice by 5.6% and 9.8% respectively;the fertilization method which basal fertilizer:tillering stage dressing:panicle fertilizer was 3:4:3 could obviously increase the content of available K in the soil after the harvest of early rice and late rice by 8.9% and 13.2% respectively.Under the condition of the combined application of 60% chemical fertilizer and 22500 kg/hm2 green manure,the fertilization method which basal fertilizer:tillering stage dressing:panicle fertilizer was 5:5:0 could significantly increase the content of available K in the soil after the harvest of early rice by 27.1% as compared with the customary fertilization method;when basal fertilizer:tillering stage dressing:panicle fertilizer was 0:10:0,the content of available N and K in the soil after the harvest of early rice or late rice was decreased.Under the condition of the combined application of 60%-80% chemical fertilizer and 22500 kg/hm2 green manure,the yield of both early rice and late rice was the highest when basal fertilizer:tillering stage dressing:panicle fertilizer was 0:7:3.