| 引用本文: | 李建菲,田鹏莹,王 娜,等.豫东平原泡桐人工林水分利用来源分析[J].灌溉排水学报,2025,44(8):33-44. |
| LI Jianfei,TIAN Pengying,WANG Na,et al.豫东平原泡桐人工林水分利用来源分析[J].灌溉排水学报,2025,44(8):33-44. |
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| 摘要: |
| 【目的】探究水资源短缺背景下豫东平原优势树种泡桐对水分胁迫的响应特征。【方法】利用稳定同位素技术测定降水、茎水和土壤水中氢氧稳定同位素（δD和δ18O），揭示不同水源δD和δ18O值的分布特征，并利用多源线性混合模型，分析不同水源对泡桐的贡献度，揭示不同季节4 a生、7 a生泡桐的水分利用特征。【结果】①在豫东平原的泡桐人工林中，土壤含水率因季节和土层而异，主要受降水影响。夏季土壤含水率较高，而春秋季较低。②0~30 cm土层土壤水中的δD、δ18O波动较大，深层土壤水δD、δ18O相对稳定，逐渐趋向平均值。③不同季节泡桐水分利用来源不同，但同一林龄不同长势泡桐在同一季节水分来源相似，贡献度略有差异。具体而言，夏季不同林龄泡桐对深层土壤水利用率较高；秋季泡桐水分来源则主要集中在0~20 cm土层，贡献度达56.7%；春季10~30 cm土层的土壤水贡献度有所增加。【结论】0~20 cm土层土壤水是泡桐的主要水源。泡桐长势越差，土壤含水率越低，表明土壤含水率是影响泡桐生长的重要因素。建议在种植过程中注意灌溉，重点保持0~20 cm土层土壤水分，保障泡桐的健康生长。 |
| 关键词: 水分利用来源；δD和δ18O；泡桐人工林；MixSIAR；豫东平原 |
| DOI：10.13522/j.cnki.ggps.2024363 |
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| Seasonal variation in root water uptake of Paulownia in Eastern Henan Plain based on stable isotopes |
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LI Jianfei, TIAN Pengying, WANG Na, TANG Wu, OU Huidi,
FAN Guoqiang, ZHAO Zhenli, ZHANG Zhihua
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1. Henan Agricultural University, Zhengzhou 450002, China;
2. Lankao County Forestry Service Center, Kaifeng 475300, China;
3. Paulownia Research Institute of Henan Agricultural University, Zhengzhou 450002, China
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| Abstract: |
| 【Objective】Paulownia is a dominant tree species in the North China Plain and plays an important ecological and economic role in this region. Due to the increasing water scarcity in this region, understanding its water-use strategies is crucial for improving water resource management and environmental protection. This paper investigates the response of Paulownia to seasonal water stress, aiming to identify water in different soil layers that the plant uses at different growth stages.【Method】The experiment was conducted in forests of four-year-old and seven-year-old Paulownia trees. Stable hydrogen and oxygen isotopes (δD and δ18O) in precipitation, xylem water and soil water at different growing stages of the trees were analyzed. Spatiotemporal variations in isotopic concentrations across the soil profile were analyzed, from which a multi-source linear mixing model were developed to calculate the contribution of water in different soil depths to the transpiration. 【Result】① Soil water content varied with season and soil depth; it was mainly influenced by precipitation. Soil water content was higher in summer and lower in spring and autumn. ② The concentration of δD and δ18O fluctuated greatly in the top 0-30 cm soil water and were relatively stable in the subsoil water. ③ Paulownia trees used water in different soil layers in different seasons. When the age of the trees was the same, they used similar soil water sources in the same season under different growth conditions. Specifically, in summer, Paulownia trees of different ages used more subsoil water, while in autumn, the water used by the trees mainly stemmed from the top 0-20 cm soil layer, which accounted for 56.7% of the transpiration. In spring, the contribution of soil water from the 10-30 cm layer to the transpiration increased.【Conclusion】Water in the top 0-20 cm layer is the main source for Paulownia trees. Poor tree growth is often due to low soil water content. Therefore, maintaining water content in the 0-20 cm layer at a certain level is essential to ensuring the healthy growth of Paulownia. |
| Key words: water use source; δD and δ18O; Paulownia plantation; MixSIAR; Eastern Henan Plain |
