Thermal trait variation may buffer Southern Ocean phytoplankton from anthropogenic warming
Thermal trait variation may buffer Southern Ocean phytoplankton from anthropogenic warming
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DOI：
10.1111/gcb.16329
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发表时间：
2022-07-17
影响因子：
11.6
通讯作者：
Rynearson, Tatiana A.
中科院分区：
文献类型：
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作者：
Bishop, Ian W.;Anderson, Stephanie I.;Rynearson, Tatiana A.
尽管长期遗传变异有可能拯救群落并塑造未来对气候变化的适应，但高度的不确定性与海洋浮游植物的种内性状变异有关。最近的模型比较表明，迫切需要减少海洋生态系统对气候变化的预测响应的不确定性，包括南大洋（SO）表层水，它们是地球上变暖最快的栖息地之一。由于 SO 浮游植物生长对变暖的海面温度 (SST) 的反应很少受到限制，因此我们开发了一种高通量生长测定法，以同时检查 43 种具有分类学多样性和生物地球化学重要性的 SO 浮游植物（硅藻）的种间和种内热性状变化。我们发现不同热特性的物种之间的生长性能存在显着差异，包括最佳和最大耐受生长温度。在物种内，相同关键热特性的菌株之间的变异系数范围为 3% 至 48%。使用 2100 年的 SO SST 预测，我们预测每个物种的最不耐受菌株和最耐受菌株之间的生物地理范围差异高达 97%，这说明了温度响应中菌株特异性差异在塑造未来浮游植物生物地理学预测中所发挥的作用。我们的研究结果揭示了 SO 浮游植物热特征变异的存在和规模，并表明这些群落可能已经拥有承受 SO 预计的 21 世纪海温变化所需的热特征多样性，即使在严重的气候强迫情景下也是如此。
Despite the potential of standing genetic variation to rescue communities and shape future adaptation to climate change, high levels of uncertainty are associated with intraspecific trait variation in marine phytoplankton. Recent model intercomparisons have pointed to an urgent need to reduce uncertainty in the projected responses of marine ecosystems to climate change, including Southern Ocean (SO) surface waters, which are among the most rapidly warming habitats on Earth. Because SO phytoplankton growth responses to warming sea surface temperature (SST) are poorly constrained, we developed a high-throughput growth assay to simultaneously examine inter- and intra-specific thermal trait variation in a group of 43 taxonomically diverse and biogeochemically important SO phytoplankton called diatoms. We found significant differential growth performance among species across thermal traits, including optimum and maximum tolerated growth temperatures. Within species, coefficients of variation ranged from 3% to 48% among strains for those same key thermal traits. Using SO SST projections for 2100, we predicted biogeographic ranges that differed by up to 97% between the least and most tolerant strains for each species, illustrating the role that strain-specific differences in temperature response can play in shaping predictions of future phytoplankton biogeography. Our findings revealed the presence and scale of thermal trait variation in SO phytoplankton and suggest these communities may already harbour the thermal trait diversity required to withstand projected 21st-century SST change in the SO even under severe climate forcing scenarios.