Abstract: Niche and interspecific association are one of the important contents in community dynamics research. Interspecific interaction affects the restoration and succession of community. In this paper, field investigation was made on the community structure of monsoonal broad-leaved evergreen forest at its different restoration stages (primary forest, PF; 15 years restoration, 15R; and 30 years restoration, 30R) in Pu’er City of Yunnan Province, and the niche breadth, niche overlap, and variance ratio (VR) as well as the chi-square test and association coefficient (AC) based on 2×2 contingency table were used to analyze the change trend of the dominant tree populations at different restoration stages. In the three communities at different restoration stages, there was a significant positive correlation (P<0.001) between the importance value and corresponding niche breadth. 78.22% of species pairs at 15R had a niche overlap 0.4-0.8, suggesting a strong resource utilization competition in dominant species; while the community structure at PF and 30R was rather stable, and the species with higher niche breadth had a higher niche overlap than those with lower niche breadth, reflecting that the dominant species had stronger competitiveness. At 15R and 30R, there was a positive interspecific association; while at PF, there was a negative association. In the three communities, most species pairs had no significant association, showed stronger independency, and the proportions of positive and negative associations decreased with the process of restoration. There was a significant positive correlation between the association coefficient and niches overlap at different restoration stages, i.e., the high the niche overlap, the greater the association coefficient.

Key words: Minqin oasis, Landscape change, Landscape index, Driving force