Key Message

Fine roots with thick diameter preferentially elongated into disturbed soil space, indicating positive invasion of pioneer roots that recolonize distal root systems.

Abstract

Fine roots and their morphological traits are related to below-ground resource dynamics at physiological and ecological levels. Established approaches for investigating fine root dynamics inevitably cause artificial soil disturbance due to root excavation or instrument installation into the soil. Soil disturbance can have considerable effects on fine root dynamics. The aim of the present study was to clarify the temporal changes of morphological traits of fine roots produced after soil disturbance. The flatbed scanner method was employed in cypress (Chamaecyparis obtusa Endl.) and deciduous oak (Quercus serrata Thunb.) stands, and changes in length and diameter of elongated roots were measured for 4 years after soil disturbance. In both stands, specific trends of diameter and length production of fine roots were observed. Root length production increased extensively, and diameter was greater in an initial phase after soil disturbance. However, temporal patterns varied between the two stands. Soil disturbance affected fine root dynamics for a longer duration in the cypress stand, but more intensively in the oak stand. These results indicate that soil disturbance can affect fine root morphology and can induce invasion of thick fine roots, which are traditionally grouped as pioneer roots. Moreover, the results showed high length production continued for a longer period than that of larger diameter roots, suggesting recolonization of fine root systems by elongating pioneer roots followed by the branching of absorptive fibrous roots in order to recover root uptake capacity lost due to soil disturbance.

中文翻译：

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用平板扫描仪方法观察到先根入侵和纤维根发育成受干扰的土壤空间

关键信息

具有较粗直径的细根优先拉长到受干扰的土壤空间中，表明先锋根正向入侵，从而重新定殖远端根系。

抽象

细根及其形态特征与生理和生态水平下的地下资源动态有关。确定的细根动力学研究方法不可避免地会因根基开挖或将仪器安装到土壤中而引起人为的土壤干扰。土壤扰动会对细根动态产生很大影响。本研究的目的是阐明土壤扰动后产生的细根形态特征的时间变化。平板扫描仪方法用于柏（Chamaecyparis obtusa Endl。）和落叶橡树（Quercus serrata）竖起），并在土壤扰动后4年内测量伸长根的长度和直径的变化。在两个林分中，均观察到细根直径和长度产生的特定趋势。在土壤扰动后的初期，根长的产生大量增加，并且直径更大。但是，两个看台之间的时间模式有所不同。在柏树林中，土壤扰动会影响细根动态，持续时间较长，而在橡树林中则更为严重。这些结果表明，土壤扰动可以影响细根形态，并且可以诱导粗细根的入侵，而细细根传统上被归类为先锋根。而且，结果表明，与较大直径的根相比，高长度的生产持续了更长的时间，