Joint Ian, Smale Dan A
The Marine Biological Association, The Laboratory, Citadel Hill, Plymouth, PL1 2PB, UK
The Marine Biological Association, The Laboratory, Citadel Hill, Plymouth, PL1 2PB, UK.
FEMS Microbiol Ecol. 2017 Feb;93(2). doi: 10.1093/femsec/fiw243. Epub 2016 Dec 8.
The response of microbial assemblages to instantaneous temperature change was measured in a seasonal study of the coastal waters of the western English Channel. On 18 occasions between November 1999 and December 2000, bacterial abundance was assessed and temperature responses determined from the incorporation of H leucine, measured in a temperature gradient from 5°C to 38°C. Q values varied, being close to 2 in spring and summer but were >3 in autumn. There was a seasonal pattern in the assemblage optimum temperature (T), which was out of phase with sea surface temperature. In July, highest H-leucine incorporation rates were measured at temperatures that were only 2.8°C greater than ambient sea surface temperature but in winter, T was ∼20°C higher than the ambient sea surface temperature. Sea surface temperatures for the adjacent English Channel and Celtic Sea for 1982-2014 have periodically been >3°C higher than climatological mean temperatures. This suggests that discrete periods of anomalously high temperatures might be close to, or exceed, temperatures at which maximum microbial assemblage activity occurs. The frequency and magnitude of marine heatwaves are likely to increase as a consequence of anthropogenic climate change and extreme temperatures may influence the role of bacterial assemblages in biogeochemical processes.
在对英吉利海峡西部沿海水域进行的一项季节性研究中，测量了微生物群落对瞬时温度变化的响应。在1999年11月至2000年12月期间的18次采样中，评估了细菌丰度，并通过在5°C至38°C的温度梯度下测量亮氨酸（H leucine）的掺入量来确定温度响应。Q值各不相同，春季和夏季接近2，但秋季大于3。群落最佳温度（T）存在季节性模式，与海面温度不同步。7月，在比周围海面温度仅高2.8°C的温度下测量到最高的亮氨酸掺入率，但在冬季，T比周围海面温度高约20°C。1982 - 2014年相邻英吉利海峡和凯尔特海的海面温度定期比气候平均温度高3°C以上。这表明异常高温的离散时期可能接近或超过微生物群落最大活动发生时的温度。由于人为气候变化，海洋热浪的频率和强度可能会增加，极端温度可能会影响细菌群落在生物地球化学过程中的作用。
