南方丘陵区典型混交林树种水分来源对降水的适应性  

Adaptation of typical mixed forest species in the southern hilly region to precipitation variation via water source changes

作　　者：武文杰 吴朝明[2] 朱骊[2] 王琳棋 戈禹[2] 张潭 刘自强 WU Wenjie;WU Chaoming;ZHU Li;WANG Linqi;GE Yu;ZHANG Tan;LIU Ziqiang(Co-Innovation Center for Sustainable Forestry in Southern China,Jiangsu Province Key Laboratory of Soil and Water Conservation and Ecological Restoration,College of Soil and Water Conservation,Nanjing Forestry University,Nanjing 210037,China;Wuxi Branch,Hydrology and Water Resources Survey Bureau of Jiangsu Province,Wuxi 214299,China;Rizhao River and Lake Management and Protection Center,Rizhao 276826,China)

机构地区：[1]南京林业大学水土保持学院,南方现代林业协同创新中心,江苏省水土保持与生态修复重点实验室,江苏南京210037 [2]江苏省水文水资源勘测局无锡分局,江苏无锡214299 [3]日照河湖管理保护中心,山东日照276826

出　　处：《南京林业大学学报(自然科学版)》2024年第6期121-128,共8页Journal of Nanjing Forestry University:Natural Sciences Edition

基　　金：国家自然科学基金青年基金项目(42377068);中国博士后科学基金项目(2022M720693);百山祖国家公园科学研究项目(2022JBGS03,2021ZDLY01)

摘　　要：【目的】基于全球气候变化背景下极端天气事件频发对植物水分利用的影响,探讨不同降水条件下南方丘陵区混交林树种对水分来源的适应性变化,为科学实施森林精准经营管理措施提供理论依据。【方法】采集不同降水量梯度下南方丘陵区麻栎(Quercus acutissima)和马尾松(Pinus massoniana)混交林的土壤和植物同位素样品,借助多元线性混合模型,对比分析不同降水梯度下麻栎和马尾松的水分利用来源。【结果】①麻栎在无降水时主要利用[10,30)cm土层的水分,利用率为62.0%;随着降水量的增加,其水源转向[80,100)cm土层的水分和地下水,大雨条件下的利用率分别为34.2%和44.6%。②马尾松在无降水时主要利用地下水和[80,100)cm土层水分,利用率分别为21.2%和21.1%;随降水量增加其水分来源逐渐向(0,10)cm和[10,30)cm土层转移,利用率分别为27.2%和53.3%。【结论】麻栎和马尾松的水分来源对降水的适应性不同,不同降水梯度下两者对土壤水分利用深度能较好地互补。在极端降水频发条件下,不同的水分利用模式有利于减少树种间水分竞争。【Objective】The frequent extreme weather events that are likely to be associated with global climate change may have an impact on plant water use.The aim of this study was to explore how mixed forest species adapt by accessing different water sources in the southern hilly region of China under different precipitation conditions.【Method】The stable hydrogen and oxygen isotopes in the xylem,soil,and groundwater from mixed Quercus acutissima and Pinus massoniana forests in the southern hilly region were measured and multi-source linear mixed models(Iso-Source)used to compare and analyze the water use in the forest under different precipitation gradients.【Result】Q.acutissima was found to mainly use soil water from the shallow layer([10,30)cm)under low precipitation conditions,with a utilization rate of 62.0%;however,under heavier rain the species turns to deep soil water([80,100)cm)and groundwater,with utilization rates of 34.2%and 44.6%,respectively.P.massoniana mainly uses groundwater and deep soil water([80,100)cm)with utilization rates of 21.2%and 21.1%,respectively,under low precipitation conditions;however,the species changes to use soil water from depths of(0,10)cm and[10,30)cm layers,with utilization rates of 27.2%and 53.3%,respectively,when precipitation increases.【Conclusion】Q.acutissima and P.massoniana adapt differently to precipitation changes in terms of the water source used,and the depth from which water is sourced changes under different precipitation gradients.The different water use patterns of these species will reduce water competition under the expected frequent extreme precipitation events expected in the future.The results of the study provide a theoretical basis for the implementation of improved forest management.

关 键 词：麻栎 马尾松 降水梯度 水分来源 氢氧同位素 

分 类 号：S715[农业科学—林学]