Structural dynamics of aspen stand in dark taiga domain in Western Sayan
We present the long-term study of spatial structure and composition of aspen stand, formed in dark taiga domian in Western Sayan after cutting of stone pine stand in 1950. Regular measurements of morphometric parameters and specifics of ontogeny of trees were employed. As shown by monitoring in 1976-2008 stone pine and fir trees, which had survived after the cutting of climax forest, gradually delayed in growth compared to deciduous species. They died after occurrence in understory in secondary deciduous forest. The stand stocking decreased due to natural thinning from 4.4 to 1.6 thousand trees ha<sup>-1 </sup>with the share of aspen decreasing from 53 to 38% and share of fir rising from 36 to 55%. On the other hand of the increased growing stock from 217 to 470 m<sup>3</sup> ha<sup>-1</sup> the share of aspen rose from 83 to 91%, while fir diminished from 12 to 6%. The leftovers were shared between birch and Siberian pine. Based on the stand and understory horizontal structure study showed significant differences in distribution and growth of wooden plants on slopes even under low area of the sampling plot (30 x 40 m), and moderate slope steepness of less than 5° when our method of study applied.