The controlling effects on Spartina alterniflora through planting various densities of Sonneratia apetala were studied conducted.The results showed that with the increasing forest density of S.apetala,S.alterniflora were more effectively controlled,especially in the planting density of 2 200 ind·hm-2.In the 2 200 ind·hm-2 forest,the light intensity was 50% of that on the non-forest meadow;the S.alterniflora coverage degree and density were less than 5%;the S.alterniflora height declined to 64%;and the above-ground biomass of S.alterniflora decreased to 9.1%,while the below-ground biomass to 27.2%.The net photosynthetic rate,stomatal conductance and transpiration rate of S.alterniflora leaves in the 2200 ind·hm-2 forest were only 26.8%,33.1% and 52.6% of those in the non-forest meadow,respectively.S.alterniflora almost subsided from the dense S.apetala forest.
