Abstract:
In this paper, the community stucture and species diversity of
Picea asperata plantations at different altitudes in Jiuzhaigou county were studied by the field experiment method. The results showed that: (1) the species composition of the arbor layer of
Picea asperata plantation was relatively single, and the understory was mainly dominated by Asteraceae, Ranunculaceae, Rosaceae, Lamiaceae and Apiaceae. The species richness was generally represented as herb layer > shrub layer > tree layer.
Lonicera szechuanica and
Rubus coreanus had great regeneration potential in shrub layer.
Thalictrum aquilegifolium was a good companion grass species in the herb layer, and the higher the altitude, the more obvious of the advantage. (2) with the increase of altitude, the growth rate of
Picea asperata significantly decreased. The average tree height of
Picea asperata at low altitude (2500 m) was about three times higher than that at high altitude (3000 m). (3) at low altitude, the crown density of
Picea asperata stands was as high as 0.9, and the coverage of shrub and grass was extremely low. At high altitude, the crown density was lower, but the coverage of understory shrub and grass, species richness and diversity were higher.