Abstract：The microenvironmental heterogeneity of near surface layer illumination of the broad-leaved Pinus koraiensis forest gap in Xiao Xing'an Mountains was analyzed by geographical statistics' method.The results show that near surface layer illumination demonstrated single peak changing tendency in the months,and the mean value was higher in June,but the maximum occurred in July.The variation of near surface layer illumination belonged to medium variation in the all observed months,and the greater variation was found in June,and the weaker variation was found in May.The differences of spatial heterogeneity of surface layer illumination were shown between different months and demonstrated single peak changing tendency.The spatial heterogeneity of autocorrelation was the main part of the total in other months except May,and showed greater variation.The light flecks were located in east of the gap,but complexities and patch grades of distribution of near surface layer illumination were different between experimental months.
2007, Vol. 5 
