This study investigated the influence of soil properties and plant age on the water use pattern of Bambusa rigida at different distances from a river during the dry season. The oxygen and hydrogen isotope compositions (δ18O and δ2H) of soil water and culm water in B. rigida forests from sites located at different distances from a river (site A: beside the river with high air moisture; site B: 200 m from the river with high clay content; site C: 400 m from the river with low clay content) were measured. Water uptake was not affected by plant age during early summer. Bambusa rigida at site A were able to use water from the soil organic horizon and moist air contributed 26% and 16% of soil water in this layer during winter and early summer. Bambusa rigida mainly took up water from soil layers with a high clay content at a depth < 50 cm due to the high water storage of these layers, although a high clay concentration weakened water uptake of bamboo roots at greater depths. This study is the first to identify the importance of air moisture for water dynamics of riparian bamboo and offers new insights into water use strategies of riparian B. rigida.

中文翻译：

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空气湿度和土壤质地对亚热带地区河岸竹的水动力学至关重要

本研究调查了旱季期间土壤性质和植物年龄对距河流不同距离的刚毛竹的水分利用模式的影响。距河流不同距离站点（站点A：在高空气湿度的河流旁；站点B：距河流200 m）的B.rigida森林土壤水和秆水的氧和氢同位素组成（δ18O和δ2H）高粘土含量的河流；C 点：距离低粘土含量的河流 400 m)。在初夏，吸水量不受植物年龄的影响。A 点的刚毛竹能够利用土壤有机层中的水，在冬季和初夏，潮湿的空气贡献了该层土壤水分的 26% 和 16%。刚毛竹主要从以下深度的粘土含量高的土层中吸水 50 cm 由于这些层的高储水量，尽管高粘土浓度削弱了竹根在更深处的吸水能力。这项研究首次确定了空气湿度对河岸竹水动力学的重要性，并为河岸竹的用水策略提供了新见解。