Arctic Research Center, Hokkaido University, Sapporo, Japan.
Hokkaido Research Organization, Forestry Research Institute, Bibai, Japan.
Sci Rep. 2022 Jul 18;12(1):12248. doi: 10.1038/s41598-022-16318-9.
Adequate management and conservation of instream thermal habitats requires an understanding of the control that different landscape features exert on water temperatures. Previous studies have extensively explored the influence of spatial scale on these relationships. However, the effect of temporal scale remains poorly understood. Here, we use paired air-water mean daily and monthly summer temperatures collected over four years from 130 monitoring stations in Japanese mid- to low-order streams to investigate whether perceived effects of different environmental controls on water temperature are dependent on the timescale of the temperature data, and whether those dependencies are related to the spatial scale at which these controls operate. We found a clear pattern for the significant cooling effect, high relative importance and strong dominance exerted by the riparian forest cover on daily temperatures at the reach scale becoming dampened by concomitant increases associated to the proportion of volcanic geology on monthly temperatures at the catchment scale. These results highlight the importance of contextualizing the effects of environmental controls on water temperatures to the timescale of the analysis. Such dependencies are particularly important for the management and conservation of instream thermal habitats in a rapidly warming world.
要充分管理和保护河流中的热生境，就需要了解不同景观特征对水温的控制作用。先前的研究已经广泛探讨了空间尺度对这些关系的影响。然而，时间尺度的影响仍知之甚少。在这里，我们使用了 130 个监测站在四年间收集的配对的空气-水日均值和夏季月均值温度，从日本中低阶河流中进行研究，以调查不同环境控制因素对水温的感知影响是否取决于温度数据的时间尺度，以及这些依赖关系是否与这些控制因素作用的空间尺度有关。我们发现了一个明显的模式，即在每日水温方面，河岸林覆盖对河流局部尺度的显著降温作用、相对重要性和强烈主导性，随着与每月水温相关的火山地质比例的增加而减弱，而这种影响在集水区尺度上变得更为明显。这些结果强调了将环境控制对水温的影响与分析的时间尺度联系起来的重要性。这种依赖性对于在快速变暖的世界中管理和保护河流中的热生境尤为重要。
