永兴县稻田肥料利用率与科学施肥对策
Fertilizer Utilization Rate of Rice Fields in Yongxing County and Crop Scientific Fertilization Countermeasures

探明永兴县稻田土壤肥力情况，弄清施肥效益与肥料利用率，可为科学施肥提供理论依据。采集永兴县52个稻田样本，其中早稻田23个，晚稻田22个，中稻田7个，设置空白区与全肥区，测定并计算早稻、晚稻与中稻土壤氮(N)、磷(P)、钾(K)含量、吸收量及肥料利用率，提出稻田土壤培肥改良对策。结果表明：早稻、晚稻与中稻平均基础产量分别为291.00kg/亩, 287.80kg/亩, 365.50 kg/亩，其中中稻空白产量显著高于早稻与晚稻(P < 0.05)。早稻、晚稻与中稻全肥区产量分别为408.80kg/亩, 395.80kg/亩, 520.70 kg/亩，呈现中稻 > 早稻 > 晚稻的趋势，且差异显著(P < 0.05)；早稻、晚稻与中稻对土壤养分的依存率分别为65.20%、65.60%、71.00%。早稻100 kg产量N:P₂O₅:K₂O吸收比例为1:0.56:1.79，晚稻比例为1:0.53:1.73，中稻比例为1:0.47:1.71。早稻、晚稻与中稻NPK综合利用率分别为66.00%、70.10%、65.10%，其中早稻与中稻NPK综合利用率均显著低于晚稻(P < 0.05)。参照《中国三大粮食作物肥料利用率研究报告》显示中国水稻N、P₂O₅和K₂O利用率分别为41.73%、12.68%、52.86%，可以看出，早稻N、P肥利用率偏低，晚稻N、P、K肥利用率偏低，中稻N、P肥利用率偏低。针对永兴县稻田土壤NPK含量、吸收量及肥料利用率，文章提出科学的稻田土壤改良与培肥建议。
The investigation of soil fertility in the rice fields of Yongxing County, along with the understanding of fertilizer efficacy and fertilizer utilization rates, can provide a theoretical basis for scientific fertilization practices. A total of 52 paddy samples were collected from Yongxing County, including 23 early rice fields, 22 late rice fields, and 7 medium rice fields. Blank areas and full fertilizer areas were set up to determine and calculate the nitrogen (N), phosphorus (P), potassium (K) content, absorption and fertilizer utilization rates of early rice, late rice and medium rice soil, and propose countermeasures for soil fertilizer cultivation and improvement in rice fields. The results showed that the average basic yields of early rice, late rice and medium rice were 291.00, 287.80, and 365.50 kg/mu, respectively, of which the blank yield of medium rice was significantly higher than that of early rice and late rice (P < 0.05). The yields of early rice, late rice and medium rice in the whole fertilizer area were 408.80, 395.80, and 520.70 kg/mu, respectively, showing the trend of medium rice > early rice > late rice, with obvious differences (P < 0.05); the dependence rates of early rice, late rice and medium rice on soil nutrients were 65.20%, 65.60%, 71.00%. The yield of 100 kg of early rice N:P₂O₅:K₂O absorption ratio is 1:0.56:1.79, the ratio of late rice is 1:0.53:1.73, and the ratio of medium rice is 1:0.47:1.71. The comprehensive utilization rate of NPK of early rice, late rice and medium rice was 66.00%, 70.10%, and 65.10%. Among them, the comprehensive utilization rate of NPK of early rice and medium rice was significantly