Nutrient resorption and stoichiometric characteristics of Wuyi rock tea cultivars

Abstract

Nutrient resorption is an important strategy for obtaining nutrition, it determines the ecosystems productivity and nutrient cycling. The Wuyi rock tea cultivars are used as important species for controlling soil erosion in hilly mountainous areas, but the mechanism of nutrient resorption is still unclear. The Wuyi Rock tea (Camellia sinensis) plantations are the main economic crops in Fujian province, China, and also have important ecological functions. The tea plants can absorb and conserve nutrients from the senesced leaves, but foliar nutrient resorptions of Wuyi Rock tea cultivars have not been well quantified. Three Wuyi Rock tea cultivars (e.g., Wuyi Jingui, Wuyi Rougui, and Wuyi Shuixian) were chosen in the Wuyishan National Soil and Water Conservation & Science and Technology Demonstration Park this study. Resorption efficiencies of nitrogen (NRE), phosphorus (PRE), potassium (KRE) and their stoichiometric characteristics were determined. KRE and NRE of the three tea cultivars were significantly higher than PRE, indicating that P was more limited than N and K. With the exception of Wuyi Rougui, the other two cultivars (Wuyi Jingui and Wuyi Shuixian) had strong stability in the leaf N and P contents under the changing soil environments. Leaf nutrient and leaf traits such as leaf thickness and specific leaf area had significant correlations with nutrient resorption efficiencies, indicating that leaf nutrient and traits can be used as indicators for nutrient resorption status. Wuyi Rock tea cultivars have strong adaptability to the environment, and they also have high carbon sequestration ability. Simultaneously, Wuyi Rock tea cultivars can reabsorb nutrients and be introduced into nutrient poor mountainous areas for soil and water conservation.