J Plant Ecol ›› 2022, Vol. 15 ›› Issue (5): 1091-1105 .DOI: 10.1093/jpe/rtac010

• Research Articles • Previous Articles    

Leaf and root phenology and biomass of Eriophorum vaginatum in response to warming in the Arctic

Ting Ma1,2, *, Thomas Parker1,3, Ned Fetcher4, Steven L. Unger5, Jon Gewirtzman6, Michael L. Moody7 and Jianwu Tang1   

  1. 1 The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA 02543, USA, 2 College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China, 3 Department of Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, UK, 4 Institute for Environmental Science and Sustainability, Wilkes University, Wilkes-Barre, PA 18766, USA, 5 Department of Biological Sciences, Florida International University, Miami, FL 33199, USA, 6 Yale School of the Environment, New Haven, CT 06520, USA, 7 Department of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968, USA

    *Corresponding author. E-mail: 467382852@qq.com
  • Received:2020-12-08 Revised:2021-03-25 Accepted:2021-10-27 Online:2022-03-01 Published:2022-09-01


The response of plant leaf and root phenology and biomass in the Arctic to global change remains unclear due to the lack of synchronous measurements of above- and belowground parts. Our objective was to determine the phenological dynamics of the above- and belowground parts of Eriophorum vaginatum in the Arctic and its response to warming. We established a common garden located at Toolik Lake Field Station; tussocks of E. vaginatum from three locations, Coldfoot, Toolik Lake and Sagwon, were transplanted into the common garden. Control and warming treatments for E. vaginatum were set up at the Toolik Lake during the growing seasons of 2016 and 2017. Digital cameras, a handheld sensor and minirhizotrons were used to simultaneously observe leaf greenness, normalized difference vegetation index and root length dynamics, respectively. Leaf and root growth rates of E. vaginatum were asynchronous such that the timing of maximal leaf growth (mid-July) was about 28 days earlier than that of root growth. Warming of air temperature by 1 °C delayed the timing of leaf senescence and thus prolonged the growing season, but the temperature increase had no significant effect on root phenology. The seasonal dynamics of leaf biomass were affected by air temperature, whereas root biomass was correlated with soil thaw depth. Therefore, we suggest that leaf and root components should be considered comprehensively when using carbon and nutrient cycle models, as above- and belowground productivity and functional traits may have a different response to climate warming.

Key words: Eriophorum vaginatum, phenology, warming, aboveground biomass, belowground biomass

北极地区的土壤和植被中存储了大量的碳,在气候变化的大背景下,北极升温速度几乎是地球其他地区的2倍。由于缺乏同步测量,尚不清楚北极地区植被地上部分和地下部分的物候和生物 量对气候变化的反应。在2016和2017年的生长季节,我们在北极的Toolik Lake站点上建立了一个移植花园,并沿纬度变化从高到低依次从 Sagwon、Toolik Lake和Coolfoot这3个站点移植了3种不同生态类型的莎草(Eriophorum vaginatum)。一半莎草用作增温处理,另一半为控制处理。我们用物候相机、手持式光谱仪和微根窗分别观测3种生态型莎草的绿色度、归一化植被指数(NDVI)和根长动态,根据NDVI和根长计算了叶片和细根的生物量。研究发现,莎草的叶和根生长是异步的,叶片开始生长的时间比根系生长的时间早约28天。气温升高1°C会延迟叶片衰老的时间,从而延长生长期,但温度升高对根系物候没有显着影响,变暖在统计学上没有增加叶片和根的生物量。此外,叶片生长的季节动态受气温的影响,但根的生长与土壤融化深度有关。因此,我们建议在使用碳和养分循环模型时,应将叶和根成分分开考虑,因为地上和地下的以及功能属性可能对气候变暖有不同的反应。

关键词: 莎草, 物候, 气候变暖, 地上生物量, 地下生物量