Large herbivores limit CO2 uptake and suppress carbon cycle responses to warming in West Greenland
Large herbivores limit CO2 uptake and suppress carbon cycle responses to warming in West Greenland
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DOI：
10.1111/j.1365-2486.2011.02528.x
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发表时间：
2012-02-01
影响因子：
11.6
通讯作者：
Welker, Jeffrey M.
中科院分区：
文献类型：
--
作者：
Cahoon, Sean M. P.;Sullivan, Patrick F.;Welker, Jeffrey M.
陆地碳循环的变化可能会缓解或加剧未来的气候变暖。关于这一主题的研究几乎完全集中在非生物驱动因素上，而生物因素，包括营养相互作用，受到的关注相对较少。我们量化的奇异和交互作用的草食动物排斥和模拟变暖对生态系统的CO2交换在西格陵兰连续两个生长季节。在过去的8年里，驯鹿和麝牛的排除导致了灌木覆盖，叶面积，生态系统光合作用的显着增加，净碳吸收量增加了近三倍。这些反应是加剧了变暖，但只有在没有食草动物。碳循环响应草食动物排除单独和结合变暖的总生态系统光合作用的变化，作为有限的差异，生态系统呼吸观察。我们的研究结果表明，大型草食动物可以作为北极生态系统对气候变化的反应的调解人至关重要。
Changes in the terrestrial carbon cycle may ameliorate or exacerbate future climatic warming. Research on this topic has focused almost exclusively on abiotic drivers, whereas biotic factors, including trophic interactions, have received comparatively little attention. We quantified the singular and interactive effects of herbivore exclusion and simulated warming on ecosystem CO2 exchange over two consecutive growing seasons in West Greenland. Exclusion of caribou and muskoxen over the past 8 years has led to dramatic increases in shrub cover, leaf area, ecosystem photosynthesis, and a nearly threefold increase in net C uptake. These responses were accentuated by warming, but only in the absence of herbivores. Carbon cycle responses to herbivore exclusion alone and combined with warming were driven by changes in gross ecosystem photosynthesis, as limited differences in ecosystem respiration were observed. Our results show that large herbivores can be of critical importance as mediators of arctic ecosystem responses to climate change.