Effect of gap size and position within gaps on growth characters and survival of chestnut-leaved oak (Quercus castaneifolia C. A. Mey.), Cappadocian maple (Acer cappadocicum Gled.) and Caucasian alder (Alnus subcordata C. A. Mey.)

In this study,six canopy gaps with medium (200-500 m2) and large (> 500m2) sizes were selected in Shastkolate forest. In each gap, micro sample plots (6×6 m) were established at the center and north, east, south and west directions of each gap. Within each micro plot, 12 seedlings of chestnut-leaved oak (Quercus castaneifolia C. A. Mey.), Cappadocian maple (Acer cappadocicum Gled.) and Caucasian alder (Alnus subcordata C. A. Mey.) were planted in spacing of 1×1 m. Height growth and photosynthetic rate of seedlings were studied during the growth season, while the survival rate was calculated in the end of season. Data were analyzed using spilt split plot plan and SNK test. Results showed that survival rate of seedlings of all three species decreased with increasing gap size. Oak seedlings showed the highest survival rate in both large and medium sized gaps. The maple seedlings showed the lowest survival rate in the large gaps. The maximum height growth of seedlings was measured in the center of gaps; this was decreased in north, west, south and east edges of the gaps, respectively. The larger the gap size the higher was the height growth of alder and oak and seedlings, while that of maple was higher in the medium gaps. Therefore one can conclude that planting of oak and alder seedlings in the center of large gaps could bring more promising results, while planting of maple in the center of medium and edges of large gaps would be more effective.