Study on Variance of Nutrient Content with Time in Pinus tabulaeformis Plantation
Zhu Jianlin Guo Jingtang Ou Guojing (Forest Resources College)
Nutrient content in Pinus tabulaeformis needles varies with season and age. According to the mode of variance, N, P, K, Ca and Mg were divided into three groups. N, P, K (declining usually but rising in some season), Ca(rising steadily with time), and Mg (relatively constant).