Intraspecific variation in root system structure in a <i>Pinus thunbergii</i> stand grown in a gravelly spit coast

Root systems of <i>Pinus thunbergii</i> planted in coastal forests exhibit high phenotypic plasticity under edaphic conditions. The objectives of this study were as follows: 1) to determine intraspecific variation in root system traits, maximum root depth and length of horizontal roots of <i>P. thunbergii</i> in a gravelly spit within a stand by excavation of entire root systems, and root system structure modelling from photographs; and 2) to determine whether the root system traits can be inferred from aboveground traits. The <i>P. thunbergii</i> trees grew twisting roots through the hard soil layer of sand and gravel and exhibited variation in root systems; most individuals had inherent tap root systems, but one had a two-tiered thick horizontal root system with a thinner tap root. Although the maximum length of the horizontal root had no relationship with the aboveground traits, the maximum root depth of <i>P. thunbergii</i> was significantly related to tree height. This suggests that tree height can be a predictive indicator of root depth, which is valuable for the rehabilitation of disaster-resistant coastal forests. Both surface and solid models of root system were produced using structure-from-motion with a multi-view stereophotogrammetry method, which enabled continuous estimation of the sum of the root cross-sectional area at any depth in the depth direction. The new method of reconstructing root system models was effective for post-analysis of traits after excavation. We concluded that intraspecific variations in the root system traits of <i>P. thunbergii</i> were observed even at the stand level on a gravelly spit coast.栽植于沿海林带的黑松（*Pinus thunbergii*）根系在土壤环境条件下表现出显著的表型可塑性。本研究的目标如下：1）通过全根系挖掘结合照片根系结构建模，明确某砾石沙洲林分中黑松的根系性状、最大根深与水平根最大长度的种内变异；2）探究能否通过地上部性状推断根系性状。 供试黑松植株的根系可穿过砂质砾石构成的硬土层形成扭曲根系，且根系存在明显种内变异：多数个体具有典型直根系，但有1株个体拥有双层厚水平根系，仅保留纤细主根。 尽管水平根最大长度与地上部性状无显著关联，但黑松的最大根深与树高呈显著相关。这表明树高可作为根深的预测指标，该结果对抗灾沿海林带的修复工作具有重要价值。 本研究采用多视图立体摄影测量法结合运动恢复结构（Structure-from-Motion, SfM）技术，构建了根系的表面模型与实体模型，可实现沿深度方向任意土层的根系横截面积总和的连续估算。 这种新型根系模型重建方法可有效用于挖掘后根系性状的后续分析。 本研究最终得出结论：即便在砾石沙洲海岸的林分尺度下，黑松的根系性状仍存在种内变异。

搜集汇总

背景与挑战

背景概述

该数据集研究了黑松（Pinus thunbergii）在砾石海岸林分中根系结构的种内变异，通过挖掘整个根系和摄影建模方法，分析了最大根深和水平根长度等性状。研究发现黑松根系在硬土层中表现出高可塑性，最大根深与树高显著相关，可用于预测根系深度，而水平根长度与地上性状无关。研究还开发了新的根系模型重建方法，有效支持了挖掘后的性状分析，为抗灾海岸林的恢复提供了科学依据。