Jiang Hao, Chen Xiaoqing, Xu Gang, Chen Jiangang, Song Dongri, Lv Ming, Guo Hanqing, Chen Jingyi
State Key Laboratory of Mountain Hazards and Engineering Resilience, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610299, China.
Key Laboratory of Mountain Hazards and Earth Surface Processes, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610299, China.
Plants (Basel). 2025 Jan 10;14(2):179. doi: 10.3390/plants14020179.
Climate change has led to an increasing frequency of droughts, potentially undermining soil stability. In such a changing environment, the shallow reinforcement effect of plant roots often fails to meet expectations. This study aims to explore whether this is associated with the alteration of plant traits as a response to environmental change. Focusing on , a species known for its robust root system that plays a crucial role in soil consolidation and slope stabilization, thereby reducing soil and water erosion, we simulated a drought-rewetting event to assess the legacy effects of drought on the soil shear strength and the mechanical and hydrological traits associated with the reinforcement provided by . The results show that the legacy effect of drought significantly diminishes the soil shear strength. Pretreated with drought, plant roots undergo morphological alterations such as deeper growth, yet the underground root biomass and diameter decline, thereby influencing mechanical reinforcement. Chemical composition analysis indicates that the plant's adaptation to drought modifies the intrinsic properties of the roots, with varying impacts on different root types and overall reinforcement. Concurrently, the stomatal conductance and transpiration rate of leaves decrease, weakening the capacity to augment soil matric suction through transpiration and potentially reducing hydrological reinforcement. Although rewetting treatments aid in recovery, drought legacy effects persist and impact plant functional attributes. This study emphasizes that, beyond soil matric suction, plant adaptive mechanisms in response to environmental changes may also contribute significantly to reduced soil shear strength. Consequently, ecological restoration strategies should consider plant trait adaptations to drought, enhancing root systems for soil conservation and climate resilience.
气候变化导致干旱频率增加，可能会破坏土壤稳定性。在这样一个不断变化的环境中，植物根系的浅层加固作用往往达不到预期。本研究旨在探讨这是否与植物性状作为对环境变化的响应而发生的改变有关。以一种根系发达、在土壤固结和边坡稳定中起关键作用从而减少水土流失的物种为研究对象，我们模拟了一次干旱-再湿润事件，以评估干旱对土壤抗剪强度以及与该物种提供的加固作用相关的力学和水文性状的遗留效应。结果表明，干旱的遗留效应显著降低了土壤抗剪强度。经过干旱预处理后，植物根系会发生形态变化，如生长更深，但地下根生物量和直径下降，从而影响力学加固作用。化学成分分析表明，植物对干旱的适应改变了根系的内在特性，对不同根系类型和整体加固作用有不同影响。同时，叶片的气孔导度和蒸腾速率降低，削弱了通过蒸腾增加土壤基质吸力的能力，并可能降低水文加固作用。尽管再湿润处理有助于恢复，但干旱遗留效应仍然存在并影响植物功能属性。本研究强调，除了土壤基质吸力外，植物对环境变化的适应机制也可能对降低土壤抗剪强度有显著贡献。因此，生态恢复策略应考虑植物性状对干旱的适应性，增强根系以保护土壤和提高气候适应能力。
