Regeneration biomass (AGB & BGB), age, NSCs and light: F. sylvatica and Acer spp.
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The Uholka-Shyrokyi Luh reserve in Ukraine belongs to beech-dominated prime forests of Europe. Total 289 target seedlings and saplings of Fagus sylvatica (100), Acer platanoides (95) and Acer pseudoplatanus (94) were randomly selected and marked according to the following criteria: three species, two vitality classes (low and high) and 8 height classes (0-10, 11-20, 21-35, 36-60, 61-90, 91-130, 131-200, 201-500 cm). Regeneration plots were deliberately selected to have the lowest diffuse radiation possible. The following measurements were taken before tree excavation in May-mid Jul 2018: diameter at root collar (DRC), tree height, height of the crown base (height of the lowest foliage, excluding epicormic shoots) and crown area projection. Crown area projection was measured by two perpendicular crown diameters using a pendulum suspended from the outermost branches to the ground. Stem height increment was measured for the recent 5-10 years (until the last visible bud scale scar) to the nearest millimetre. Leaf area index (LAI) and indirect site factor (ISF), i.e. the proportion of diffuse solar radiation at a given location relative to that in the open, were assessed with hemispherical photos (Coolpix 4500, Nikon, Japan). Biomass processing: The sampled trees were separated at the root collar into aboveground biomass (foliage, stem, branches) and belowground biomass (root). All fresh leaves per tree were scanned with a smartphone (Petiole, version 2.0.1, Petiole Ltd. 2019) after calibration of the camera. Foliage, stems, branches, and roots were dried at 65 °C for three days until a constant weight and then weighed to the nearest 0.01 g. NSCs analysis: Fresh pieces of 5 cm length from the stem at the level of the root collar and from the coarse roots (diameter >2 mm) were cut for NSC analysis and placed in a microwave at 900 W twice for 15 s immediately after harvest. The coarse root sections of bigger saplings (2-4 cm DRC) were limited to 5 to 10 mm diameter and the harvested stem sections to 10 mm of wood directly under bark. Dendrochronological analysis: From each harvested tree, a stem disc was cut at the level of the root collar using a microtome to determine age and radial growth. The stained discs were photographed (Canon EOS 700D) and analysed with WinDENDRO™ (Regent Instrument Canada Inc.) under a microscope. The number and width of the rings were measured in 2-4 perpendicular directions because of the excentric tree piths, and then arithmetically averaged
乌克兰乌霍尔卡-希罗基卢赫（Uholka-Shyrokyi Luh）保护区隶属于欧洲山毛榉主导的原始森林。本研究共随机选取并标记了289株目标实生苗与幼树，涵盖欧洲山毛榉（Fagus sylvatica，100株）、挪威槭（Acer platanoides，95株）与假挪威槭（Acer pseudoplatanus，94株），选取标准如下：3个树种、2个活力等级（低、高）以及8个高度等级（0-10、11-20、21-35、36-60、61-90、91-130、131-200、201-500 cm）。研究样地刻意选择为散射辐射最低的区域。2018年5月至7月中旬，在挖掘树木前完成了以下测量：根颈直径（DRC）、树高、冠基高度（即最低叶片高度，不含萌蘖枝）以及冠幅投影面积。冠幅投影面积通过悬挂摆锤从最外侧枝条垂至地面，测量两个垂直方向的冠径来计算。针对近5-10年的茎高生长量（测量至最后一个可见的芽鳞痕处），测量精度精确至毫米。叶面积指数（LAI）与间接立地因子（ISF，即特定位置的散射太阳辐射占开阔区域散射辐射的比例），通过半球摄影法（尼康Coolpix 4500，日本尼康）进行评估。生物量处理流程如下：将采样树木在根颈处分为地上生物量（叶片、茎干、枝条）与地下生物量（根系）。在对相机完成校准后，使用智能手机（Petiole，版本2.0.1，Petiole有限公司2019年）扫描每棵树的全部新鲜叶片。将叶片、茎干、枝条与根系置于65℃烘箱中干燥3天至恒重，随后称重至0.01 g精度。非结构性碳水化合物（NSCs）分析：从根颈处的茎干以及粗根（直径>2 mm）上截取5 cm长的新鲜样品用于NSCs分析，取样后立即置于900 W微波炉中处理两次，每次15秒。对于根颈直径2-4 cm的较大幼树，其粗根样本限定截取直径为5-10 mm的部分；茎干样本则截取树皮下方10 mm厚的木质部。树木年代学分析：从每棵采收树木的根颈处截取茎干圆盘，使用显微切片机进行处理以确定树龄与径向生长量。将染色后的圆盘拍照（佳能EOS 700D），并在显微镜下使用WinDENDRO™（加拿大Regent仪器公司）进行分析。由于树髓偏心，在2-4个垂直方向测量年轮的数量与宽度，随后进行算术平均。
