Transient Effects of Snow Cover Duration on Primary Growth and Leaf Traits in a Tundra Shrub

Frontiers in Plant Science

Valentino Casolo¹  Francesco Boscutti¹  Angela Luisa Prendin²  Raffaella Dibona³  Marco Carrer³  Lucrezia Unterholzner³  Roberto Menardi³  Sara Gargiulo⁴ 

[1] Department of Agricultural Food Environmental Animal Sciences, University of Udine, Udine, Italy;Department of Biology, Ecoinformatics and Biodiversity, Aarhus University, Aarhus, Denmark;Department of Land Environment Agriculture and Forestry, University of Padova, Legnaro, Italy;Department of Life Sciences, University of Trieste, Trieste, Italy;

关键词: snowmelt;    alpine tundra;    shrub phenology;    Juniperus communis;    leaf traits;    non-structural carbohydrates;   

DOI  :  10.3389/fpls.2022.822901

来源: DOAJ

【 摘 要 】

With the recent climate warming, tundra ecotones are facing a progressive acceleration of spring snowpack melting and extension of the growing season, with evident consequences to vegetation. Along with summer temperature, winter precipitation has been recently recognised as a crucial factor for tundra shrub growth and physiology. However, gaps of knowledge still exist on long-living plant responses to different snowpack duration, especially on how intra-specific and year-to-year variability together with multiple functional trait adjustments could influence the long-term responses. To fill this gap, we conducted a 3 years snow manipulation experiment above the Alpine treeline on the typical tundra species Juniperus communis, the conifer with the widest distributional range in the north emisphere. We tested shoot elongation, leaf area, stomatal density, leaf dry weight and leaf non-structural carbohydrate content of plants subjected to anticipated, natural and postponed snowpack duration. Anticipated snowpack melting enhanced new shoot elongation and increased stomatal density. However, plants under prolonged snow cover seemed to compensate for the shorter growing period, likely increasing carbon allocation to growth. In fact, these latter showed larger needles and low starch content at the beginning of the growing season. Variability between treatments slightly decreased over time, suggesting a progressive acclimation of juniper to new conditions. In the context of future warming scenarios, our results support the hypothesis of shrub biomass increase within the tundra biome. Yet, the picture is still far from being complete and further research should focus on transient and fading effects of changing conditions in the long term.

【 授权许可】

Unknown