水肥耦合对娃娃菜叶球养分吸收和土壤理化性质的影响

Effects of water and fertilizer coupling on nutrient absorption and soil physicochemical properties of mini Chinese cabbage

为探明河西冷凉灌区秋茬娃娃菜节水节肥、高产高效的科学灌溉施肥制度,以‘金皇后’为试材,研究了膜下滴灌条件下3个灌溉水平:60%θ_(f)(低水,H1)、70%θ_(f)(中水,H2)、80%θ_(f)(高水,H3)和3个施肥水平:N 281-P_(2)O_(5)166-K_(2)O 383 kg·hm^(-2)(低肥,F1)、N 330-P_(2)O_(5)195-K_(2)O 450 kg·hm^(-2)(中肥,F2)、N 380-P_(2)O_(5)224-K_(2)O 518 kg·hm^(-2)(高肥,F3)组合对娃娃菜叶球养分吸收和土壤理化性质的影响。结果表明:水肥用量与娃娃菜田土壤理化性质和叶球氮磷钾吸收量关系密切,H2F2处理可在一定程度上改善娃娃菜田土壤的理化性质,维持土壤酸碱平衡,提高叶球养分含量,增加养分累积量。水肥耦合模式下,H2F2处理较H3F3处理娃娃菜叶球氮、磷、钾吸收量分别提高4.72%、3.26%、3.22%。H2F2处理水平下基于隶属函数与标准差系数权重法取得的水肥耦合效应综合得分最高,且较H3F3处理提高7.13%。综合考虑娃娃菜田土壤理化性质和叶球氮磷钾吸收量,灌水下限控制在70%θf、施肥量N 330-P_(2)O_(5)195-K_(2)O 450 kg·hm^(-2)是适合甘肃河西走廊冷凉灌区露地膜下滴灌秋茬娃娃菜最优的水肥管理模式。

The purpose of this study was to explore the scientific irrigation and fertilization system of water saving,fertilizer saving,high yield and high efficiency of autumn crop mini Chinese cabbage in cold irrigation area of Hexi.The mini Chinese cabbage planted in autumn was the research object in the study.‘Gold Queen’was used as a test material.The effects of three irrigation water volumes(H1,H2,H3)combined with three fertilizer amounts(F1,F2,F3)on nutrient absorption and soil physicochemical properties of mini Chinese cabbage under drip irrigation were studied.The results showed that the amount of water and fertilizer was closely related to the soil physical and chemical properties and nutrient absorption.The medium water and fertilizer treatment improved the physical and chemical properties of the soil of mini Chinese cabbage field to a certain extent,maintained the soil acid-base balance,and increased the nutrient content of mini Chinese cabbage leaf ball as well as the accumulation of nutrient in the leaf ball.Under the coupling mode of water and fertilizer,the absorption of nitrogen,phosphorus and potassium in the leaf ball of H2F2 treatment was higher than that of H3F3 treatment by 4.72%,3.26% and 3.22%,respectively.The comprehensive score of water and fertilizer coupling effect obtained by using the membership function of principal component combined with weight was the highest in H2F2 treatment,and 7.13%higher than that of high water and high fertilizer treatment,which was the optimal water and fertilizer combination in this experiment.Taking into account the soil’s physical and chemical properties and nutrient absorption,an irrigation level of 70%field capacity combined with a fertilizer application of N 330-P_(2)O_(5)195-K_(2)O 450 kg·hm^(-2)represents the optimal water and fertilizer management strategy for autumn mini Chinese cabbage in the cold irrigation areas of the Hexi Corridor.