Concentration, accumulation and distribution characteristics of nutrient elements in Parashorea chinensis plantation

The concentration, accumulation and distribution of five nutrient elements, including N, P, K, Ca, Mg, were studied in 32 years old Parashorea chinensis plantation stand in southwest of Guangxi. The results showed that the concentration of these five nutrient elements in different components of P. chinensis was roughly in the order of leaf > bark > branch > root > stem. The content of N was the highest in leaf, while the content of Ca was the highest in other components, followed by N, P and Mg, the content of K was the lowest. The total accumulations of five nutrient elements in P. chinensis was 2 451.65 kg/hm2, showed as Ca > N > Mg > P > K. The annual net accumulation of these five nutrient elements was 76.61 kg/hm2. The net production of organic matter per ton needed 7.12 kg of these five elements in tree layer, the Ca elements amount was the biggest, followed by the N, Mg and P, and the K was the smallest. The order of accumulation of nutrient elements in P. chinensis was stem > bark > leaf > branch > root. The average contents of N, P, K elements in shrub layer, herb layer and litter layer were slightly larger than those in tree layer, and the accumulation of three nutrient elements were 7.69, 13.58, 64.89 kg/hm2, respectively.