养殖废水灌溉对大蒜生长、产量及水氮利用效率的影响

Effects of livestock wastewater irrigation on growth,yield,and water and nitrogen use efficiency of garlic

【目的】利用田间小区试验,研究养殖废水灌溉对大蒜生长、产量、水氮利用效率及土壤总氮的影响,以期促进养殖废水的回收利用,减少大蒜水资源和氮肥用量,为养殖废水灌溉节水减排提供科学依据。【方法】在国家农业环境大理观测实验站开展了大蒜养殖废水灌溉试验研究。试验根据不同灌溉水源和施氮水平设5个处理(CK:清水灌溉+不施氮肥,C1:清水灌溉+全量氮肥390 kg/hm^(2),C2:清水灌溉+减量氮肥312 kg/hm^(2),R1:养殖废水灌溉+不施氮肥,R2:养殖废水灌溉+施用氮肥150kg/hm^(2)),分析比较不同处理下大蒜各生育期生长指标、产量、水氮利用效率和土壤总氮的变化规律。【结果】R2处理下大蒜生长发育状况最佳,R1处理在较低施氮水平下达到C1处理水平的生长指标;R2的大蒜产量最佳,C1、C2、R1、R2处理鳞茎产量分别比CK提高111.30%、81.23%、98.19%、142.01%;相比C1处理,养殖废水灌溉(R1和R2处理)下氮肥吸收利用率分别提高154.71%和92.25%,氮肥偏生产力分别提高110.75%和47.63%,灌溉水分生产率的相对变化分别为-29.19%和2.34%,0~40cm土层的土壤总氮增量分别降低9.25%和3.89%,但0~20cm土层的土壤总氮增量提高170.90%和255.93%。【结论】养殖废水灌溉和施用适量氮肥有助于大蒜生长发育和产量形成,在不灌清水和减量氮肥的同时保证大蒜生长和产量,提高了表层土壤含氮量。

【Objective】Garlic is a cash crop in Dali,but its irrigation with livestock wastewater risks environmental pollution.This paper studies the combined effect of livestock wastewater irrigation and nitrogen fertilization on growth,yield,water and nitrogen utilization efficiency of garlic,as well as soil nitrogen in attempts to screen a sustainable livestock wastewater irrigation schedule for garlic production in this region.【Method】The experiment was conducted at the National Agricultural Environmental Dali Observation and Experimental Station.There were five treatments:freshwater irrigation without nitrogen application(CK),freshwater irrigation with 390 kg/hm 2 of nitrogen application(C1),freshwater irrigation with 312 kg/hm^(2) of nitrogen application(C2),livestock wastewater irrigation without nitrogen application(R1),livestock wastewater irrigation with 150 kg/hm^(2) of nitrogen application(R2).In each treatment,we measured the growth indexes,including dry weight,height,stem diameter and leaf area index of the garlic at different growing stages,as well as yield,and water and nitrogen use efficiency of the garlic and soil nitrogen content.【Result】The growth of the garlic was the best in R2,but was comparable with that in R1 and C1;R2 gave the highest yield.Compared to CK,C1,C2,R1 and R2 increased the bulb yield by 111.30%,81.23%,98.19%,and 142.01%,respectively.The nitrogen absorption and use efficiency of R1 and R2 was 154.71%and 92.25%higher than that of C1,respectively;the nitrogen partial factor productivity of R1 and R2 was 110.75%and 47.63%higher than that of C1,respectively.Compared to C1,R1 reduced the irrigation water productivity and soil nitrogen in the 0-40 cm of soil layer by 29.19%,while R2 increased the irrigation water productivity by 2.34%and reduced soil nitrogen in the 0-40 cm of soil by 3.89%,respectively.Compared to C1,R1 and R2 increased nitrogen in the 0-20 cm of soil layer by 170.90%and 255.93%respectively.【Conclusion】Livestock wastewater irrigation combined with appropriate base nitrogen fertilization can sustain garlic growth and yield.Livestock wastewater irrigation improved the nitrogen use efficiency and nitrogen partial factor productivity,with limited effect on average soil total nitrogen.