Plos Carolin, Hensen Isabell, Korell Lotte, Auge Harald, Römermann Christine
German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig Leipzig Germany.
Institute of Biology, Geobotany and Botanical Garden, Martin Luther University Halle-Wittenberg Halle (Saale) Germany.
Ecol Evol. 2024 May 23;14(5):e11441. doi: 10.1002/ece3.11441. eCollection 2024 May.
Phenological shifts due to changing climate are often highly species and context specific. Land-use practices such as mowing or grazing directly affect the phenology of grassland species, but it is unclear if plants are similarly affected by climate change in differently managed grassland systems such as meadows and pastures. Functional traits have a high potential to explain phenological shifts and might help to understand species-specific and land-use-specific phenological responses to changes in climate. In the large-scale field experiment (GCEF), we monitored the first flowering day, last flowering day, flowering duration, and day of peak flowering, of 17 herbaceous grassland species under ambient and future climate conditions, comparing meadows and pastures. Both climate and land use impacted the flowering phenology of plant species in species-specific ways. We did not find evidence for interacting effects of climate and land-use type on plant phenology. However, the data indicate that microclimatic and microsite conditions on meadows and pastures were differently affected by future climate, making differential effects on meadows and pastures likely. Functional traits, including the phenological niche and grassland utilization indicator values, explained species-specific phenological climate responses. Late flowering species and species with a low mowing tolerance advanced their flowering more strongly under future climate. Long flowering species and species following an acquisitive strategy (high specific leaf area, high mowing tolerance, and high forage value) advanced their flowering end more strongly and thus more strongly shortened their flowering under future climate. We associated these trait-response relationships primarily with a phenological drought escape during summer. Our results provide novel insights on how climate and land use impact the flowering phenology of grassland species and we highlight the role of functional traits in mediating phenological responses to climate.
由于气候变化导致的物候变化通常具有高度的物种特异性和环境特异性。割草或放牧等土地利用方式会直接影响草地物种的物候，但尚不清楚在诸如草地和牧场等不同管理的草地系统中，植物是否同样受到气候变化的影响。功能性状很有可能解释物候变化，并且可能有助于理解物种特异性和土地利用特异性的物候对气候变化的响应。在大规模田间试验（GCEF）中，我们监测了17种草本草地物种在当前和未来气候条件下的始花期、终花期、花期持续时间和盛花期，比较了草地和牧场。气候和土地利用均以物种特异性方式影响植物物种的开花物候。我们没有发现气候和土地利用类型对植物物候有交互作用的证据。然而，数据表明，草地和牧场的小气候和微生境条件受未来气候的影响不同，这可能对草地和牧场产生不同的影响。包括物候生态位和草地利用指标值在内的功能性状解释了物种特异性的物候气候响应。晚花物种和低耐割性物种在未来气候下开花提前得更明显。花期长的物种和采取获取性策略（高比叶面积、高耐割性和高饲用价值）的物种在未来气候下终花期提前得更明显，从而花期缩短得更明显。我们将这些性状-响应关系主要与夏季的物候干旱逃避联系起来。我们的研究结果为气候和土地利用如何影响草地物种的开花物候提供了新的见解，并且我们强调了功能性状在介导物候对气候的响应中的作用。
