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The study was undertaken in Scots pine shelterwood forests in central Anatolia at the edge of the Eurasian distribution of Scots pine and thus adding signi cance in terms of understanding the ecology of this important species. Canopy gap size and the position of the sapling within the regeneration cores were chosen within nine di erent strip-sample plots comprising 20 sapling regeneration cores. Those sapling regeneration cores under the gaps were divided into two portions (individuals at the edge and middle of the regeneration cores) and from each portion three individuals were selected. The growth relationships of individual saplings within the regenera-tion cores were determined from the age-height graph of 95 sapling-stem analyses. Gap-size classes that compromise a gap size gradient were chosen: small gaps (< 20 m2); intermediate gaps (20 - 177 m2); large gaps (178 - 707 m2). Spatial structure of mature trees were determined using the Clark-Evans index. In addition, di erentiation index (diameter, height, crown lenght, and crown radius) were calculated for each stand projections. Gaps with sapling regeneration cores ranged from 15 to 240 m2, with a mean of 91.55 ± 23.69 m2 by Student's t-test (p = 0.05). The maximal gap-size classes were found in the intermediate (90%), followed by large (5%) and small (5%). Compared with saplings in the middle of regeneration cores, those at the edge were always reduced in terms of mean height. Signi cant di erence was found between the ‘Main crop' and the ‘Edges 1-2' of the regeneration cores. There was no signi cant di erence for sapling age in regeneration cores. Fraction of land area in gap regeneration cores was found between 20 and 66% of total stand area. The age-height graph of 95 saplingstems derived from stem analyses showed that the saplings grow very well without any obvious deceleration in the gaps. These ndings can further inform forest managers about how to optimize growth of sapling by means of canopy gap regulation. The results are discussed in the context of future silvicultural modelling and new ways of assessing forest regeneration dynamics when gap-regeneration is important. [ABSTRACT FROM AUTHOR]

Aims: With its diverse vascular flora Turkey is well-known as a bridge between the Mediterranean basin, the Caucasus, and the Irano-Turanian region. Orchids are an important component of this diversity with 191 taxa, of which 39 taxa are Turkish endemics. This study aims to group the country's orchid taxa into different phytogeographical regions, natural vegetation types, and altitudinal zones. Study area: Turkey. Methods: Field surveys were carried out from 1988 to 2017. The sampling areas were selected with good prior knowledge of orchid-containing terrains and habitats. Distribution data were revised and presented in a 10 km UTM grid. Geospatial data were classified and processed by ArcGIS software. Results: The Mediterranean region (70 taxa, 17 endemics) is the richest for orchid taxa distributed in only one phytogeographical region, followed by the Euro-Siberian (13 taxa, 2 endemics) and the Irano-Turanian (7 taxa, all endemics) regions. Species richness per habitat varied from Mediterranean landscapes of "natural Pinus brutia forests" (105 taxa, 12 endemics), followed by landscapes with "Quercus frainetto forest" (59 taxa, 3 endemics), "Oak-hornbeam forest" (55 taxa, 3 endemics), "Beech-spruce forest" (38 taxa, 1 endemic), "Quercus brantii forest steppe (arid)" (38 taxa, 5 endemics) to "Subalpine Juniper forest steppe" (34 taxa, 7 endemics). Orchids were found mainly at elevations of 0 to 500 m (138 taxa) and 501 to 1,000 m (123 taxa). At elevations over 1,000 m, the number of orchid taxa decreases, but 21 taxa were found at over 2,000 m. Some orchid taxa were found to be restricted to a particular altitudinal zone and phytogeographical region. Conclusion: This study provides a general framework for relevant orchid conservation efforts in Turkey. Key habitats from different phytogeographical regions and altitudinal zones should be prioritised. For such areas, a multi-layered conservation planning approach from country to habitat level across Turkey needs to be developed. Complementary approaches should be promoted in neighbouring countries too. [ABSTRACT FROM AUTHOR]