Abstract: The methods of frequency distribution comparison and aggregation index measurement are applied for the research of the natural regeneration patterns of Chinese pine(Pinus tabtaeformis)populaticn. Under semi-arid ecological conditions, the natural regeneration pattern of Chinese pine population is showed to conform with the truncated negative binormial distribution, which belongs to the type pf aggregated distribution. This kind of pattern with higher aggregation intensity is considered to be the best way of distribution for Chinese pine population to survive under unfavorable ecological conditions such as drought and sterile and to reproduce. It prfoundly reveals the biological and ecological characters of Chinese pine population from a different view.

Key words: irrigation low limit, Festuca arundinacea, green period, cold resistance, water use efficiency