摘要
Abstract
The application of acidic substances can regulate soil alkalinity and reduce ammonia volatilization.Inorganic liquid acid is convenient to add to liquid fertilizer,which has the functions of both fertilization and the soil alkalinity improvement.In this experiment,acidic liquid fertilizer was applied to soils with different pH to explore the difference of ammonia volatilization.A total of five acidic liquid fertilizers with the same nutrient content but different pH levels were used,with their pH adjusted to 6.5,4.7,1.9,1.0,and 0 using dilute sulfuric acid.In the indoor ammonia volatilization culture experiment,five different pH fertilizers(0.6 g/kg soil)were mixed and applied to black meadow soil,fluvo-aquic soil and soda saline-alkali soil.There were 5 treatments(pH 6.5,pH 4.7,pH 1.9,pH 1.0,pH 0)for each type of soil,with no fertilization as the control.During the 30 d incubation period,the ammonia volatilized from the soil was collected and measured by static absorption method at multiple time periods.The ammonia volatilization of black meadow soil reached the peak at 16 h-1 d after culture,fluvo-aquic soil at 8 h-1 d,and soda saline-alkali soil at 16 h-1 d.The total amount of ammonia volatilization during the culture period was related to the pH of the liquid fertilizer,with higher pH resulting in more ammonia volatilization.The total amount of ammonia volatilization was 31.5-45.2 mg/kg,accounting for 19.4%-27.9%of the nitrogen application rate,and it was 30.4%lower in pH 0 treatment than that in pH 6.5 treatment.The total amount of ammonia volatilization in fluvo-aquic soil was 37.3-61.2 mg/kg,accounting for 23.0%-37.8%of nitrogen application,and it was 39.1%lower in pH 0 treatment than that in pH 4.7 treatment.The total amount of ammonia volatilization in soda saline-alkali soil was 51.3-72.8 mg/kg,accounting for 37.1%-45.0%of the nitrogen application rate,and it was 29.5%lower in pH 0 treatment than that in pH 6.5 treatment.The ammonia volatilization of acidic liquid fertilizer in alkaline soil occurred in the first three days.When the same pH liquid fertilizer was applied,the total amount of ammonia volatilization showed soda saline-alkali soil>fluvo-aquic soil>black meadow soil,indicating that the higher the soil pH,the more ammonia volatilization.The total amount of ammonia volatilization after 30 d of culture in the three soils was at pH 0 treatment,indicating that the lower the pH of the liquid fertilizer,the less the total amount of ammonia volatilization.关键词
酸性液体肥/氨挥发/碱性土壤Key words
acid liquid fertilizers/ammonia volatilization/alkaline soil
