Regeneration pattern of Picea schrenkiana var. tianschanica forest under two different disturbances.

Using a point-pattern analysis method, the natural regeneration pattern of Picea schrenkiana var. tianschanica forests under two types of disturbance (namely canopy disturbance and intense selection cutting disturbance) was studied in west China's Xinjiang Uygur Autonomous Region. The results indicate that under canopy disturbance, the naturally regenerated seedlings in the canopy gaps present a cluster distribution pattern and have a largest cluster intensity in every distribution. There exist spatially dependent relationships between naturally regenerated seedlings and gap-makers. Under intense selection cutting disturbance, the saved trees in P. schrenkiana var. tianschanica forests present cluster distribution pattern in the sample plots investigated (130 m×80 m in size). The relationships between naturally regenerated seedlings and saved trees show an embedded clot, random arrangement and spatial dependence according to the magnitude of the spatial scale. And spatial dependence exists between naturally regenerated seedlings and felled trees, similar to the relationship between seedlings and gap-makers in P. schrenkiand var. tianschanica forests.