Abstract: Box-counting dimension reflects the spatial occupation degree of an object. The box-counting dimension of population pattern discloses the spatial occupation degree of population and its scale variation degree, the inflection point indicates the aggregating scale of individuals. This study analyzed the scale variation degrees of the spatial patterns of Larix gmelini populations in several typical forest types in Daxingan mountains, China using box-counting dimension. The results showed that the spatial distributions of Larix gmelini populations were high(>1.5, near 2) in different types of Larix gmelini forests, which reflected the high spatial occupation degrees of the populations as the dominant species of these forest types. The order of spatial occupation degree was Vaccinium-Larix forest (1.829) > Grass-Larix forest (1.720) > Rhododendron-Larix forest (1.705) > Ledum-Larix forest (1.513). The Box-counting dimension of Larix gmelini population was lower (1.371, far from 2) in Larix-Betula mixed forest, which showed the low spatial occupation degree of the populations in accompaniment position in the forest. Comparisons on box-counting dimensions of Larix gmelini populations among natural forests and that of plantation showed that, the order of spatial occupation degree was Larix plantation (1.868) > Natural Larix forest (1.692) > Larix-Betula forest (1.371), which reflected the variation of functions and positions of Larix gmelini population in different forest types.

Key words: Larix gmelini, Population pattern, Box-counting dimension, Spatial occupation, Scale