Hawai'i Cooperative Studies Unit, University of Hawai'i at Hilo, Hawai`i National Park, Hawai'i, United States of America.
U.S. Geological Survey, Pacific Island Ecosystems Research Center, Kīlauea Field Station, Hawai'i National Park, Hawai'i, United States of America.
PLoS One. 2019 Jun 20;14(6):e0218516. doi: 10.1371/journal.pone.0218516. eCollection 2019.
Montane plant communities throughout the world have responded to changes in temperature regimes by shifting ranges upward in elevation, and made downslope movements to track shifts in climatic water balance. Organisms that cannot disperse or adapt biologically to projected climate scenarios in situ may decrease in distributional range and abundance over time. Restoration strategies will need to incorporate the habitat suitability of future predicted conditions to ensure long-term persistence. We propagated seedlings of three native Hawaiian montane plant species from high- (2,500 m asl) and low-elevation (1,900 m asl) sources, planted them in 8 common plots along a 500 m elevation gradient, and monitored microclimate at each plot for 20 weeks. We explored how temperature and precipitation influenced survival and growth differently among high- and low-elevation origin seedlings. Significantly more seedlings of only one species, Dodonaea viscosa, from high-elevation origin (75.2%) survived than seedlings from low-elevation origin (58.7%) across the entire elevation gradient. Origin also influenced survival in generalized linear mixed models that controlled for temperature, precipitation, and elevation in D. viscosa and Chenopodium oahuense. Survival increased with elevation and soil moisture for Sophora chrysophylla, while it decreased for the other two species. Responses to microclimate varied between the three montane plant species; there were no common patterns of growth or survival. Although limited in temporal scope, our experiment represents one of the few attempts to examine local adaptation to prospective climate scenarios and addresses challenges to restoration efforts within species' current ranges.
世界各地的山地植物群落通过向上迁移海拔范围来应对温度格局的变化，并向下坡移动以追踪气候水分平衡的变化。那些不能通过生物扩散或适应来应对预测气候情景的生物，随着时间的推移，其分布范围和丰度可能会减少。恢复策略将需要结合未来预测条件的栖息地适宜性，以确保长期生存。我们从高海拔 (2500 米海拔) 和低海拔 (1900 米海拔) 来源繁殖了三种夏威夷本地山地植物物种的幼苗，将它们种植在 8 个常见的 500 米海拔梯度的斑块中，并在 20 周内监测每个斑块的小气候。我们探讨了温度和降水如何不同地影响高海拔和低海拔来源的幼苗的存活和生长。仅有一种植物 Dodonaea viscosa 的高海拔来源的幼苗（75.2%）比低海拔来源的幼苗（58.7%）在整个海拔梯度上存活的数量更多。起源也通过控制 Dodonaea viscosa 和 Chenopodium oahuense 中的温度、降水和海拔的广义线性混合模型影响了其生存。Sophora chrysophylla 的存活率随海拔和土壤湿度的升高而升高，而其他两种植物的存活率则降低。三种山地植物物种对小气候的反应不同；没有共同的生长或存活模式。尽管在时间范围上有限，但我们的实验是少数试图检验对未来气候情景的本地适应的尝试之一，并解决了在物种当前范围内恢复努力面临的挑战。
