PDF(Pubmed)
Abstract：
BACKGROUND: Understanding how trees develop their root systems is crucial for the comprehension of how wildland and urban forest ecosystems plastically respond to disturbances such as harvest, fire, and climate change. The interplay between the endogenously determined root traits and the response to environmental stimuli results in tree adaptations to biotic and abiotic factors, influencing stability, carbon allocation, and nutrient uptake. Combining the three-dimensional structure of the root system, with root morphological trait information promotes a robust understanding of root function and adaptation plasticity. Low Magnetic Field Digitization coupled with AMAPmod (botAnique et Modelisation de l\'Architecture des Plantes) software has been the best-performing method for describing root system architecture and providing reliable measurements of coarse root traits, but the pace and scale of data collection remain difficult. Instrumentation and applications related to Terrestrial Laser Scanning (TLS) have advanced appreciably, and when coupled with Quantitative Structure Models (QSM), have shown some potential toward robust measurements of tree root systems. Here we compare, we believe for the first time, these two methodologies by analyzing the root system of 32-year-old Pinus ponderosa trees.
RESULTS: In general, at the total root system level and by root-order class, both methods yielded comparable values for the root traits volume, length, and number. QSM for each root trait was highly sensitive to the root size (i.e., input parameter PatchDiam) and models were optimized when discrete PatchDiam ranges were specified for each trait. When examining roots in the four cardinal direction sectors, we observed differences between methodologies for length and number depending on root order but not volume.
CONCLUSIONS: We believe that TLS and QSM could facilitate rapid data collection, perhaps in situ, while providing quantitative accuracy, especially at the total root system level. If more detailed measures of root system architecture are desired, a TLS method would benefit from additional scans at differing perspectives, avoiding gravitational displacement to the extent possible, while subsampling roots by hand to calibrate and validate QSM models. Despite some unresolved logistical challenges, our results suggest that future use of TLS may hold promise for quantifying tree root system architecture in a rapid, replicable manner.
RESULTS: In general, at the total root system level and by root-order class, both methods yielded comparable values for the root traits volume, length, and number. QSM for each root trait was highly sensitive to the root size (i.e., input parameter PatchDiam) and models were optimized when discrete PatchDiam ranges were specified for each trait. When examining roots in the four cardinal direction sectors, we observed differences between methodologies for length and number depending on root order but not volume.
CONCLUSIONS: We believe that TLS and QSM could facilitate rapid data collection, perhaps in situ, while providing quantitative accuracy, especially at the total root system level. If more detailed measures of root system architecture are desired, a TLS method would benefit from additional scans at differing perspectives, avoiding gravitational displacement to the extent possible, while subsampling roots by hand to calibrate and validate QSM models. Despite some unresolved logistical challenges, our results suggest that future use of TLS may hold promise for quantifying tree root system architecture in a rapid, replicable manner.
摘要：
背景：了解树木如何发育其根系对于理解荒地和城市森林生态系统如何对收获等干扰进行塑性反应至关重要，火,和气候变化。内生决定的根系性状与对环境刺激的反应之间的相互作用导致树木对生物和非生物因素的适应。影响稳定性，碳分配，和营养吸收。结合根系的三维结构，根形态性状信息促进了对根功能和适应可塑性的强大理解。低磁场数字化与AMAPmod（botAniqueetModelisationdel\'ArchitecturedesPlantes）软件相结合，是描述根系体系结构并提供可靠的粗根性状测量的最佳执行方法，但是数据收集的速度和规模仍然很困难。与地面激光扫描（TLS）相关的仪器和应用已经取得了长足的进步，当与定量结构模型(QSM)结合使用时，已经显示出一些对树根系统进行稳健测量的潜力。在这里我们比较,我们第一次相信,这两种方法通过分析32岁的黄松树的根系。
结果：一般来说，在总根系统级别和根序类，两种方法都产生了可比较的根系性状体积值，长度,和数量。每个根性状的QSM对根大小高度敏感(即，输入参数PatchDiam）和模型在为每个性状指定离散PatchDiam范围时进行了优化。当检查四个基本方向扇区的根时，我们观察到长度和数量的方法之间的差异取决于根顺序，而不是体积。
结论：我们相信TLS和QSM可以促进快速数据收集，也许在原地，在提供定量准确性的同时，尤其是在整个根系水平。如果需要更详细的根系统架构措施，TLS方法将受益于不同视角的额外扫描，尽可能避免重力位移，同时手工二次采样根以校准和验证QSM模型。尽管有一些尚未解决的后勤挑战，我们的结果表明，未来使用TLS可能有望快速量化树根系统架构，可复制的方式。
结果：一般来说，在总根系统级别和根序类，两种方法都产生了可比较的根系性状体积值，长度,和数量。每个根性状的QSM对根大小高度敏感(即，输入参数PatchDiam）和模型在为每个性状指定离散PatchDiam范围时进行了优化。当检查四个基本方向扇区的根时，我们观察到长度和数量的方法之间的差异取决于根顺序，而不是体积。
结论：我们相信TLS和QSM可以促进快速数据收集，也许在原地，在提供定量准确性的同时，尤其是在整个根系水平。如果需要更详细的根系统架构措施，TLS方法将受益于不同视角的额外扫描，尽可能避免重力位移，同时手工二次采样根以校准和验证QSM模型。尽管有一些尚未解决的后勤挑战，我们的结果表明，未来使用TLS可能有望快速量化树根系统架构，可复制的方式。
