[Dynamics of nutrients in an age sequence of Pinus massoniana plantation].
By using a chronosequence approach, this paper studied the nutrients accumulation, allocation, and cycling in 7-, 17-, 31-, and 51-year-old Masson pine plantations, aimed to analyze the dynamics of nutrients in Masson pine plantation at its different developmental stages. The results showed that 1) nutrient accumulation was not synchronized with biomass accumulation, with the accumulation rate of biomass being 3.3, 5.4, 3.3, 3.7, and 9.8 times of that of N, P, K, Ca, and Mg from age 17 to 51, respectively, 2) nutrient allocation to a specific component was related to the growth rate of the nutrient pool in the component, and the nutrient allocation to stem as well as the ratio of nutrient allocation to root/shoot increased with plantation age, and 3) the biomass production per unit nutrient, i. e., nutrient use efficiency, and the nutrient cycling coefficient also increased with plantation age, being higher for 51-year-old plantation than for younger plantations, suggesting that shortening the rotation length could reduce the possibility to raise the nutrient use efficiency. It was suggested that both extending the current rotation length to as long as 50 years and reducing the harvest intensity could be helpful to conserve the nutrients and to maintain long-term productivity.
Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China. yhx-s@163.com
Hui-Xia
HX
Yang
Si-Long
SL
Wang
Bing
B
Fan
Wei-Dong
WD
Zhang
Cui-E
CE
Wei
D018533:Biomass; D009751:Nutritional Requirements; D028223:Pinus / Q000254:growth & development* / Q000378:metabolism*; D013997:Time Factors