Dynamics and Distribution of Nutrition Elements in Bamboos

Mao bamboo (Phyllostachys pubescens) with a high production and wide utilization has been planted in large scale in southern China, but little information about bamboo nutrition is available. The objective of this study was to reveal the dynamics of nutrition with growing time and the distribution of nutrition in different organs. It was found that the nutrition concentration of the whole plant generally declined with time during the period of 1-6 weeks owing to a dilution effect with the result of quickly increasing the biomass. The leaf concentration of nitrogen (N), phosphorus (P), and potassium (K) changed regularly with high concentrations observed at age 1, 2, 4, and 6, and lower at age 3 and 5. While the concentration of N, P, and K in the branch and stem generally declined with the weeks, a rapid decrease occurred from weeks 1 to 2. The concentrations of calcium (Ca) and magnesium (Mg) in bamboo leaf, branch, and stem appeared to be opposite to those of N, P, and K in corresponding plant parts. The elemental concentrations were greater (P 0.05) in the leaves than in the branches and stems, while the storage of nutrition was greater (P 0.05) in stem than in leaves and branch. A relative large total storage of nutrition, except P and Mg, were found in bamboo under an intensive management (IM) stand than those under extensive management (EM) stand. The total storage of different nutritions in the above-ground parts was in the order: K (243.0-285.6 kg ha-1) N (154.5-207.8 kg ha-1) P (10.4-12.2 kg ha-1). The nutrition stored in the bamboo plant would be removed away from the soil in every other year by the means of harvest of the bamboo trunk which is the largest nutrition pool of the bamboo plant. Therefore, supplementary nutrients, especially N and K, are strongly recommended in order to keep the productivity of bamboo.