基于养分专家系统的水稻磷肥减施潜力研究

为探究养分专家系统推荐施肥下磷肥用量的减施潜力,进而为不同肥力水平稻田磷肥减施提供理论依据,在高、中、低肥力稻田上,通过在养分专家系统推荐施肥基础上增减15%、30%、45%磷肥用量开展双季稻田间试验,并分析磷肥用量与水稻产量的量化关系。结果表明,在高、中、低肥力稻田上,养分专家系统推荐施肥处理的早、晚稻产量均呈高肥力>中肥力>低肥力的趋势,而与之比较,在其基础上磷肥增施15%、30%、45%处理对早、晚稻产量均无显著增产效应,减施15%处理未显著减产,但磷肥减施45%处理在各肥力水平稻田上均显著减产,降幅为4.06%~15.15%。高、中、低肥力稻田上早、晚稻产量潜力对应磷肥合理用量呈低肥力>高肥力>中肥力稻田的趋势,且在95%的产量潜力下,在养分专家系统推荐施肥量基础上,早稻季不同肥力水平稻田上可减施磷肥27.09%~57.58%,晚稻季可减施磷肥33.25%~50.53%,其中早、晚稻磷肥可减施比例高肥力稻田为27.09%、49.51%,中肥力稻田为36.20%、50.53%,低肥力稻田为33.25%、57.58%。在养分专家系统推荐施肥量基础上,可在不同肥力水稻田上实现磷肥减施,但减施比例有所差异,整体上高肥力稻田磷肥可减施比例较中、低肥力稻田低。

Potential of Phosphate Fertilizer Reduction on the Benchmark of Rice Nutrient Expert System

To explore the potential for reducing phosphorus fertilizer amount on the benchmark of rice nutrient expert system, and then provide a theoretical basis for reducing phosphorus fertilizer in paddy rice fields with different soil fertility levels, a double-cropping rice field experiment was conducted to analyze the relation of the amount of phosphorus fertilizers to rice yield in high, middle and low soil fertility rice fields by increasing or decreasing 15%, 30% and 45% of the amount of phosphorus fertilizer recommended by the rice nutrient expert system. The results showed that, in high, medium and low soil fertility rice fields, the treatment with the amount recommend by the rice nutrient expert system had a yield trend of high fertility>medium fertility>low fertility for both early rice and late rice, the treatments with the phosphorus amount increased by 15%, 30% and 45% had not a significant increased effect on rice yield for both early rice and late rice, and the treatment with the phosphorus amount reduced by 15% had not a significant decreased effect on rice yield for both early rice and late rice. However, the treatment with 45% of phosphate fertilizer reduction had a significantly-reduced rice yield by 4.06% to 15.15% in various soil fertility fields. The reasonable amount of phosphate fertilizer corresponding to the yield potential for early rice and late rice in high, medium and low soil fertility fields had a trend of low fertility>high fertility>medium fertility, and with 95% of the yield potential and based on the amount recommended by the nutrient expert system, the amount of phosphorus fertilizer could be reduced by 27.09% to 57.58% for early rice and 33.25% to 50.53% for late rice in various soil fertility fields, among which the reducible rate of phosphate fertilizer was 27.09%, 49.51% in high soil fertility field, 36.20%, 50.53% in medium soil fertility field and 33.25%, 57.58% in low soil fertility field, for early rice and late rice, respectively. In summary, the amount of phosphorus fertilizer can be reduced on the amount recommended by the nutrient expert system in different fertility rice fields, but the reducible rate is different. Generally, the reducible rate of phosphate fertilizer is lower in high fertility rice field than that in medium and low fertility rice fields.