Department of Geography, University of Bonn, Meckenheimer Allee 166, Bonn, D-53115, Germany.
Department of Natural Sciences and Environmental Health, University of South-Eastern Norway, Gullbringvegen 36, Bø, N-3800, Norway.
Commun Biol. 2022 Aug 6;5(1):793. doi: 10.1038/s42003-022-03741-x.
Under climate change, cold-adapted alpine ecosystems are turning into hotspots of warming. However, the complexity of driving forces of growth, associated biomass gain and carbon storage of alpine shrubs is poorly understood. We monitored alpine growth mechanisms of six common shrub species across contrasting biomes, Mediterranean and tundra, using 257 dendrometers, recording stem diameter variability at high temporal resolution. Linking shrub growth to on-site environmental conditions, we modelled intra-annual growth patterns based on distributed lag non-linear models implemented with generalized additive models. We found pronounced bimodal growth patterns across biomes, and counterintuitively, within the cold-adapted biome, moisture, and within the drought-adapted biome, temperature was crucial, with unexpected consequences. In a warmer world, the Mediterranean alpine might experience strong vegetation shifts, biomass gain and greening, while the alpine tundra might see less changes in vegetation patterns, minor modifications of biomass stocks and rather browning.
在气候变化下，适应寒冷的高山生态系统正变成变暖的热点。然而，高山灌木生长、相关生物量增益和碳储存的驱动因素的复杂性还了解甚少。我们使用 257 个树轮计，以高时间分辨率记录茎直径变化，监测了对比生物群落（地中海和苔原）中六种常见灌木物种的高山生长机制。我们将灌木生长与现场环境条件联系起来，基于广义加性模型实现的分布式滞后非线性模型，对年内生长模式进行建模。我们发现，在整个生物群落中存在明显的双峰生长模式，而且与直觉相反，在寒冷适应的生物群落中，水分至关重要，而在干旱适应的生物群落中，温度是关键因素，这带来了意想不到的后果。在一个更温暖的世界中，高山地中海地区可能会经历强烈的植被转变、生物量增益和绿化，而高山苔原地区的植被模式变化可能较小，生物量储量的修改也较小，而更多的是变褐。
