Laws of annual nutrient uptake of 8-yr.-old paulowia (Paulownia Sieb. et Zucc.)plantation (spacing in row 6m, row spacing 10m) in Fengqiu paulownia experimental spot in Huanghuaihai plain was studied for 2 years by using scientific methods and became clear. Annual total uptakes of 5 macronutrients (N, P, K, Ca, and Mg) in 1989 and 1990 were 287.3238 and 242.4234Kg/hm2 a respectively. The study found the following laws, (1 ) the nutrient uptakes of different paulownia organs came in the following order: foliage> branches > flowers> stems> roots, (2) the uptake of different nutrient elements came in the following sequence: N> Ca> K> P> Mg, (3)paulownia’s uptake rate of nutrient elememnts was mainly conducted during the period between the beginning of growth and the end of July.
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