TundraTime: Plant phenology change as a driver of Arctic greening trends

TundraTime：植物物候变化是北极绿化趋势的驱动因素

• 批准号: NE/W006448/1
• 负责人: Claudia Colesie
• 金额: $ 76.89万
• 依托单位: University of Edinburgh
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FW006448%2F1
• 关键词: TundraTime; Plant; phenology; change; driver

The TundraTime project will address climate change impacts in tundra ecosystems including how warming is shifting tundra plant phenology - the timing of life events such as bud burst or flowering - and productivity - the increase in plant growth and biomass over time. We will answer the fundamental research question of whether climate warming is leading to longer tundra growing seasons and thus increasing plant productivity in the Arctic, with important implications for carbon cycling and wildlife. Critical knowledge gaps in the field of global change ecology are what role the high latitudes will play in the global carbon cycle and how Arctic food webs will be restructured in the future with accelerated warming. A critical unknown is whether shifting plant phenology is altering tundra carbon cycling and wildlife habitats. Projections of climate feedbacks from high-latitude ecosystems remain uncertain as we do not yet know if carbon losses from warming soils will be offset by increases in tundra productivity. Tundra plant responses to warming could be key for understanding the fate of wildlife populations in a rapidly changing Arctic. Forty years of satellite and field observations have revealed widespread changes in the tundra's surface that protects large stocks of frozen carbon below. Field studies indicate that plants are coming into leaf earlier in spring, bare ground is becoming vegetated, and plants are now growing taller. While there is scientific consensus that climate change is reshaping Arctic ecosystems, great uncertainty persists about what the greening observed from space means in terms of change on-the-ground.The TundraTime project will answer the fundamental research questions of whether climate warming is leading to longer periods of plant growth and increases in plant productivity in the Arctic. We will test specific hypotheses of whether tundra ecosystems are experiencing: A) increases in productivity, B) shifts in phenology and C) asynchrony of above- and below-ground plant growth. To explore these questions, we will integrate high-resolution drone and time-lapse camera imagery with satellite and in-situ data from 12 focal Arctic research sites. Our findings will inform biome-wide projections of tundra vegetation change and global-scale predictions of climate feedbacks to unprecedented rates of warming.If tundra plant productivity is responding directly to the warmer and longer Arctic growing seasons then tundra productivity will trap more carbon in tundra ecosystems and restructure wildlife habitats. However, if instead tundra plant growing seasons are shifting earlier, then projections of increases in tundra vegetation with warming may be overestimates and earlier timing of key forage could alter migratory behaviour and ultimately wildlife populations. And, if the above- and below-ground responses of tundra plants are asynchronous, plant growth in the now extended snow-free autumns could instead be occurring below ground, which would overturn how satellite data and Earth-system models estimate plant productivity and carbon storage in warming tundra ecosystems. The TundraTime project will test the drivers of Arctic greening by resolving the uncertainty around what role shifting plant phenology plays in the increased tundra productivity with warming. This research will bridge critical scale gaps to resolve the uncertainty between satellite and in-situ observations of changes in the timing of plant growth with accelerating climate warming.

TundraTime项目将解决苔原生态系统中的气候变化影响，包括气候变暖如何改变苔原植物物候--花蕾爆裂或开花等生命事件的发生时间--以及生产力--植物生长和生物量随着时间的推移而增加。我们将回答基本研究问题，即气候变暖是否导致冻土带生长季节延长，从而提高北极的植物生产力，对碳循环和野生动物具有重要影响。全球变化生态学领域的关键知识空白是高纬度地区将在全球碳循环中扮演什么角色，以及未来随着全球变暖的加速，北极食物网将如何重组。一个关键的未知因素是，植物物候的变化是否正在改变冻土带的碳循环和野生动物的栖息地。对高纬度生态系统气候反馈的预测仍然不确定，因为我们还不知道土壤变暖造成的碳损失是否会被冻土带生产力的增加所抵消。苔原植物对气候变暖的反应可能是了解快速变化的北极地区野生动物种群命运的关键。四十年的卫星和实地观测揭示了冻土带表面的广泛变化，这些变化保护了下面大量冻结的碳。实地研究表明，植物在春天更早地长出叶子，裸露的土地正在变得植被茂盛，植物现在正在长得更高。尽管科学上已经达成共识，认为气候变化正在重塑北极生态系统，但从太空观察到的绿化对地面变化意味着什么，这一点仍然存在巨大的不确定性。TundraTime项目将回答气候变暖是否导致北极植物生长更长时间和植物生产力提高的基本研究问题。我们将测试冻土带生态系统是否正在经历的具体假设：A)生产力增加，B)物候变化，C)地上和地下植物生长不同步。为了探索这些问题，我们将把高分辨率无人机和延时相机图像与来自12个北极重点研究地点的卫星和现场数据结合起来。我们的发现将为整个生物群对冻土带植被变化的预测以及对全球范围气候反馈到前所未有的升温速度的预测提供信息。如果冻土带植物生产力直接对北极更温暖和更长的生长季做出反应，那么冻土带生产力将在冻土带生态系统中捕获更多的碳，并重新构建野生动物栖息地。然而，如果冻土带植物的生长季节正在提前转移，那么冻土带植被随着变暖而增加的预测可能被高估了，更早地选择关键饲料的时间可能会改变迁徙行为，最终改变野生动物种群。而且，如果冻土带植物在地上和地下的反应是不同步的，那么现在延长的无雪秋季的植物生长可能会发生在地下，这将颠覆卫星数据和地球系统模型对变暖的冻土带生态系统中植物生产力和碳储量的估计。TundraTime项目将测试北极绿化的驱动因素，通过解决植物物候变化在随着气候变暖而增加的苔原生产力中扮演什么角色的不确定性。这项研究将弥合关键的尺度差距，以解决卫星和现场观测之间的不确定性，即随着气候变暖的加速，植物生长时间的变化。

项目成果

Plant diversity dynamics over space and time in a warming Arctic

变暖的北极植物多样性随空间和时间的变化

• DOI: 10.32942/x2ms4n
• 发表时间: 2023
• 作者: García Criado M

Plant traits poorly predict winner and loser shrub species in a warming tundra biome.

• DOI: 10.1038/s41467-023-39573-4
• 发表时间: 2023-06-28
• 期刊: NATURE COMMUNICATIONS
• 影响因子: 16.6
• 作者: Criado, Mariana Garcia;Myers-Smith, Isla H.;Bjorkman, Anne D.;Normand, Signe;Blach-Overgaard, Anne;Thomas, Haydn J. D.;Eskelinen, Anu;Happonen, Konsta;Alatalo, Juha M.;Anadon-Rosell, Alba;Aubin, Isabelle;te Beest, Mariska;Betway-May, Katlyn R.;Blok, Daan;Buras, Allan;Cerabolini, Bruno E. L.;Christie, Katherine;Cornelissen, J. Hans C.;Forbes, Bruce C.;Frei, Esther R.;Grogan, Paul;Hermanutz, Luise;Hollister, Robert D.;Hudson, James;Iturrate-Garcia, Maitane;Kaarlejaervi, Elina;Kleyer, Michael;Lamarque, Laurent J.;Lembrechts, Jonas J.;Levesque, Esther;Luoto, Miska;Macek, Petr;May, Jeremy L.;Prevey, Janet S.;Schaepman-Strub, Gabriela;Sheremetiev, Serge N.;Collier, Laura Siegwart;Soudzilovskaia, Nadejda A.;Trant, Andrew;Venn, Susanna E.;Virkkala, Anna-Maria
• 通讯作者: Virkkala, Anna-Maria

The tundra phenology database: more than two decades of tundra phenology responses to climate change

苔原物候数据库：二十多年来苔原物候对气候变化的响应

• DOI: 10.1139/as-2020-0041
• 发表时间: 2022
• 期刊: Arctic Science
• 影响因子: 3.3
• 作者: Prevéy J

Summer litter decomposition is moderated by scale-dependent microenvironmental variation in tundra ecosystems

苔原生态系统中尺度相关的微环境变化调节了夏季凋落物的分解

• DOI: 10.1111/oik.10261
• 发表时间: 2023
• 期刊: Oikos
• 影响因子: 3.4
• 作者: Gallois E