Abstract:

To study the relationship between soil acidity and exchangeable hydrogen and aluminium in the main tea gardens of Guangxi, and to provide technical support for the scientific cultivation of tea trees and the improvement of acidified soil, 290 soil samples were collected from the tea tree planting areas in Guangxi, and their pH values, exchangeable hydrogen and aluminum contents were analyzed. The results show that the pH value of the soil in the tea-growing areas of Guangxi fluctuates greatly, ranging from 3.11 to 6.89. 66.55% of the soil samples have a pH value lower than 4.5, and the soil in the tea gardens is extremely acidic. The smaller the pH value, the greater the content of exchangeable acids. Exchangeable acid is the main factor affecting soil pH value. When the pH value is low, the content of exchangeable H⁺ and exchangeable Al³⁺ will be higher. There is a significant linear positive correlation between soil exchangeable acid and exchangeable H⁺ and exchangeable Al³⁺ With the increase of the contents of H⁺ and Al³⁺, soil exchangeable acid will also increase accordingly. The contribution of exchangeable Al³⁺ to soil acidity is greater than that of exchangeable H⁺ to soil acidity. It can be seen that the soil in tea gardens in Guangxi is severely acidified. In production, soil acidity improvement should be carried out in a timely manner.

Key words: Guangxi, tea plantation, soil acidification, exchangeable acid