Response of Soil and Plant Nutrients to Planting Years in Precious Ancient Camellia tetracocca Plantations

Abstract

In order to explore the response of soil nutrient supply capacity and tea plant nutrient utilization capacity to tea-planting years in precious ancient tea garden, field investigation and indoor analysis methods were employed to research the soil and plant nutrient content, eco-stoichiometric characteristics and the correlation between them, with artificially bred Camellia tetracocca at different time periods (5 years, 15 years, 25 years and 40 years). The results showed that: (1) the contents of soil organic carbon and total nitrogen were higher in the 25- and 40-year teas than in 5- and 15-year teas. The soil pH and total phosphorus were the highest in the 40-year tea, and the available nutrient content was the lowest in the 40-year tea. (2) The contents of nitrogen, phosphorus and potassium in tea shoots were the highest in 15-year tea. The nutrient content of tea trees were highest according to the following order: new shoots > leaves > branches. (3) The N: P of soil and leaves was 4.11–7.55 and 6.37–11.76, respectively. Available nutrients and soil pH were the main factors affecting the contents of nitrogen, phosphorus and potassium in new shoots. In conclusion, the soil nutrient supply capacity and the nutrient utilization capacity of tea plants in the Camellia tetracocca garden were significantly different under different tea-planting years. The growth of the tea plants was restricted by the soil nitrogen supply. The nutrient absorption and utilization capacity of precious Camellia tetracocca were higher in the 15- and 25-year teas, respectively. The study provides the basis for the rational development and sustainable utilization of precious ancient tea plants, and the scientific management of tea gardens.