摘要
植物物候对气候变暖的响应是全球气候变化研究的重要内容。目前,高海拔生态系统植物物候对气候变暖响应的研究仍然较少。该研究依托西藏那曲高寒草地生态系统国家野外科学观测研究站布设的梯度增温实验,分别于2015、2017、2018和2021年对模拟增温下优势物种高山嵩草(Kobresia pygmaea)和钉柱委陵菜(Potentilla saundersiana)返青期、现蕾期和开花期等表征植物物候的指标进行了观测,以期揭示增温下藏北高寒草甸植物物候变化机制。结果表明:随着温度升高,高寒草甸中优势植物物候具有不同的变化趋势。高山嵩草返青、现蕾和开花物候期的推迟幅度与温度升高幅度呈正相关关系;钉柱委陵菜返青、现蕾和开花时间随着温度上升表现为先提前后推迟;这表明高寒草甸植物物候对增温产生异步响应。此外,长期增温下的藏北高寒草甸优势种的物候变化均显示出了延迟效应。结构方程归因分析发现,空气温度升高促使高山嵩草返青时间推迟;低水平增温可以促进钉柱委陵菜物候提前,而随着温度继续升高其物候响应发生逆转,土壤水分在决定物候对气候变暖响应的幅度和方向上具有关键作用。该研究结果揭示了藏北高寒草甸优势植物物候响应气候变暖的异步性特征,为预测未来高海拔生态系统对气候变化的响应提供了数据支撑。
Aims The response of plant phenology to climate warming is an important element of global change research.At present,studies on plant phenology response to climate warming are in severe shortage for high-altitude ecosystems,especially regarding responses to multiple-level warming.Methods We conducted a multiple-level warming experiment in an alpine meadow on Qingzang Plateau,and monitored plant phenology of two dominant species,including the timing of green up,budding and flowering in 2015,2017,2018 and 2021.Important findings The results showed that plant phenology of different species exhibited various trends under warming.For Kobresia pygmaea,delay in phenological development,including green up,budding and flowering,was positively correlated with temperature increases.However,the timing of phenological stages of Potentilla saundersiana showed advancing first,and then delay with increasing temperature.These results suggest that plant phenology of alpine meadow asynchronously responds to increased temperature.In addition,temperature increase exerts delayed effects on plant phenology over long-term.The structural equation modeling showed that temperature increase consistently delayed the green up of K.pygmaea,and low-level warming advanced phenological development of P.saundersiana,but this advancing trend reversed under high-level warming.Importantly,soil moisture plays a key role in determining the magnitude and direction of phenological response to climate warming in our study.Our findings indicate the asynchronous characteristics of plant phenology response to climate warming in alpine meadow ecosystems,and provide basis to predict responses of high-altitude ecosystems to climate change in the future.
作者
夏璟钰
张扬建
郑周涛
赵广
赵然
朱艺旋
高洁
沈若楠
李文宇
郑家禾
张雨雪
朱军涛
孙建新
XIA Jing-Yu;ZHANG Yang-Jian;ZHENG Zhou-Tao;ZHAO Guang;ZHAO Ran;ZHU Yi-Xuan;GAO Jie;SHEN Ruo-Nan;LI Wen-Yu;ZHENG Jia-He;ZHANG Yu-Xue;ZHU Jun-Tao;SUN Osbert Jianxin(School of Ecology and Nature Conservation,Beijing Forestry University,Beijing 100083,China;Nagqu Alpine Grassland Research Station,Key Laboratory of Ecosystem Network Observation and Modeling,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China;Peking University Shenzhen Graduate School,Shenzhen,Guangdong 518055,China)
出处
《植物生态学报》
CAS
CSCD
北大核心
2023年第2期183-194,共12页
Chinese Journal of Plant Ecology
基金
国家自然科学基金(U20A2009、41991234和42077422)
国家重点研发计划(2017YFA0604802)
关键词
高寒草地
异步响应
梯度增温
植物物候
温度敏感性
alpine meadow
asynchronous response
multiple-level warming
plant phenology
temperature sensitivity
