Experimental plot
The total experimental area was 4.4 hectares consisting of the three plots:
(I): 4.0 hm2, manganese tailing site amended with an organic manure as a base fertilizer to increase the nutrient availability and reduce the metal toxicity in the rhizosphere before transplanting one-year old seedlings of P. fortunei andK. bipinnata (spacing 2-2.5m, 1000 plants of each species/hm2).
(II): 0.2 hm2, manganese tailing site amended with equivalent amounts of chemical fertilizers in the rhizosphere before transplanting one-year old seedlings of the same tree species (spacing 2-2.5m, 1000 plants of each species/hm2) and
(III): 0.2 hm2, uncontaminated site in the vicinity of the tailing wasteland, a plant community naturally developed under normal soil conditions.