Abstract:

To explore the physicochemical indexes and nutrient status of tea plantations in the main tea producing areas of Yibin City, and to better guide the scientific application of fertilizers and soil nutrient management in local tea plantations, field surveys and soil sampling were conducted in five major tea-producing districts and counties of Yibin City. The pH and nutrient elements (Ca, Mg, Zn, Mn, Fe, Cu, K, P and Al) of tea plantation soils were tested as well as nutrient indexes such as total nitrogen and total carbon, and nutrient grades were analyzed and evaluated. The results showed that: (1) the pH of tea garden soil in the main tea producing areas of Yibin City was between 3.95 and 6.90, and some areas showed a trend of acidification. (2) According to the grading standards of effective state trace elements and nutrient contents in tea garden soils, the effective K nutrients of tea garden soils in the main production areas presented a very rich state; most of the contents of Fe, Zn, Cu, Mn and Al were in grade Ⅰ and Ⅲ, presenting a rich and suitable state. (3) Nearly half of the tea areas were relatively deficient in elemental P and total nitrogen; Ca and Mg showed a tendency to be deficient throughout the tea areas; and the total carbon content was low. In short, the overall soil fertility of 0-40 cm soil layer in the main tea producing areas of Yibin City was higher. It is suggested that the application of organic fertilizer should be strengthened in tea garden management to adjust soil pH and increase total carbon content. Nitrogen fertilizer should be supplemented appropriately in some tea areas, and calcium and magnesium fertilizer should be applied in all tea producing areas to achieve scientific fertilization.

Key words: Yibin City, tea plantations soil, nutrient elements, total nitrogen, total carbon