Reproductive collapse in European beech results from declining pollination efficiency in large trees.
Reproductive collapse in European beech results from declining pollination efficiency in large trees.
复制标题
欧洲山毛榉的繁殖衰退是由于大树授粉效率下降造成的。
DOI：
10.1111/gcb.16730
复制
发表时间：
2023
影响因子：
11.6
通讯作者：
Bogdziewicz M
中科院分区：
文献类型：
--
作者：
Bogdziewicz M
气候变暖增加了树木的死亡率，这将需要足够的繁殖来确保种群的生存能力。然而，树木繁殖对气候变化的反应仍然知之甚少。气候变暖会降低种子生产的同步性和年际变异性（“桅杆崩溃”），这会增加种子捕食，降低树木的授粉效率。在这里，使用40年的观察，在欧洲山毛榉（山毛榉）的个人种子生产，我们表明，桅杆故障的结果，随着时间的推移，在下降的可行的种子生产，相反的积极趋势明显的原始种子计数数据。此外，树的大小调制桅杆故障可行的种子生产的后果。虽然种子捕食主要是在小树随着时间的推移而增加，授粉效率不成比例地下降较大的个人。因此，繁殖力下降，随着时间的推移，在所有大小类，但整体效果是最大的大树。我们的研究表明，一种基本的生物学关系--树木大小和种子产量之间的相关性--随着气候变暖而逆转。这种逆转对森林动态有不同的影响，包括林分和地理水平的森林更新动态。树的大小效应建议管理选项，以增加森林在不断变化的气候下的恢复力。
Climate warming increases tree mortality which will require sufficient reproduction to ensure population viability. However, the response of tree reproduction to climate change remains poorly understood. Warming can reduce synchrony and interannual variability of seed production (“masting breakdown”) which can increase seed predation and decrease pollination efficiency in trees. Here, using 40 years of observations of individual seed production in European beech (Fagus sylvatica), we showed that masting breakdown results in declining viable seed production over time, in contrast to the positive trend apparent in raw seed count data. Furthermore, tree size modulates the consequences of masting breakdown on viable seed production. While seed predation increased over time mainly in small trees, pollination efficiency disproportionately decreased in larger individuals. Consequently, fecundity declined over time across all size classes, but the overall effect was greatest in large trees. Our study showed that a fundamental biological relationship—correlation between tree size and viable seed production—has been reversed as the climate has warmed. That reversal has diverse consequences for forest dynamics; including for stand‐ and biogeographical‐level dynamics of forest regeneration. The tree size effects suggest management options to increase forest resilience under changing climates.