The previous article explained the effect of humic acid on soil enzyme activity. Today we will continue to explain the effect of humic acid on the structure and quantity of soil microorganisms.
Humic acid can affect the number and diversity of microorganisms in the soil.
Research shows that the combined application of humic acid and fertilizer increases the number of bacteria, fungi and actinomycetes in the rhizosphere soil under sugarcane planting conditions, and as the amount of humic acid added (10~40kg/ha) increases, the number of various microorganisms increases. It shows a trend of increasing first and then decreasing. When 30kg/ha of humic acid and fertilizer are applied together, the number of microorganisms is the largest; and humic acid has different effects on different types of microorganisms. Among them, the effect on bacteria is the greatest, followed by fungi. Minimal impact on actinomycetes.
Studies have shown that humic acid can inhibit changes in the composition and quantity of microbial communities such as ammonifying bacteria and ammonifying archaea by reducing the rate at which urea in the soil is hydrolyzed to ammonia and buffering soil pH, buffering the effects of urea application on cell diversity in the soil. and the total amount, thereby reducing the rate at which ammonia is oxidized into nitrite and nitric acid, and reducing the loss caused by denitrification into nitrogen, ultimately allowing more nitrogen to be absorbed and utilized by plants, which is beneficial to plant growth and crop yield increase. All are of great significance.
In summary, humic acid can promote the growth of plants by affecting the structure and quantity of soil microorganisms. It can be regarded as a good soil conditioner and plant growth promoter.