Abstract: With natural Pinus koraiensis population as test object, and by the methods of growth equation regression analysis and partition fitting determination, this paper studied the neighborhood interference radius of P. koraiensis at various slope locations. The results showed that there was a significant negative cor-relation between the neighborhood interference index and the growth of P. koraiensis, and the correlation level varied with neighborhood interference zone and slope. The interference zone corresponding to the maximal regression coefficient R² was considered as the neighborhood interference radius. Based on the linear subsection regression between neighborhood interference index and interference zone, the neighborhood interference index increased fast and then slowly as the zone expanded, and the interference zone corresponding to the transition point was considered as the neighborhood interference radius. The neighborhood interference index was positively correlated with neighborhood interference zone, and the range of R² was 0.41～0.55. The neighborhood interference radius of P. koraiensis varied with slope locations in the order of lower slope=upper slope＞middle slope.

Key words: Maize plant type, Roots distribution