Unraveling the mysteries of the large watershed black box: Implications for the streamflow response to climate and landscape perturbations
Unraveling the mysteries of the large watershed black box: Implications for the streamflow response to climate and landscape perturbations
复制标题
揭开大流域黑匣子的神秘面纱：水流对气候和景观扰动响应的影响
DOI：
--
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Fengjing Liu
中科院分区：
文献类型：
--
作者：
M. Frisbee;F. Phillips;G. Weissmann;P. Brooks;John L. Wilson;Andrew R. Campbell;Fengjing Liu
河流化学的空间和时间趋势已被用来提供对小流域河流生成过程的尺度依赖性的见解。然而，这些尺度依赖性尚未在大流域尺度（定义为大于1000平方公里的流域）上进行彻底调查。量化这些尺度依赖性对于理解大流域如何对未来的扰动作出反应至关重要；例如，河流对气候变化和/或土地覆盖和土地利用变化的长期响应。本文研究了科罗拉多州落基山脉南部一个大型高山流域中所有主要水流生成过程的时空尺度关系。流域观测结果表明，主要的径流过程具有空间和时间上的差异性。主要水流机制的相对强度随流域内部结构（即地形起伏、土壤发育、地下水流道发育和水系网络结构的空间变异性）和降水时间和特征等外部强迫而变化。这种行为与先前的观测结果相结合，即来自流域的水流含有流域尺度地下水的重要组成部分，这表明类似的大流域可能具有内部缓冲，至少在最初，可以应对快速变化。
Spatial and temporal trends in stream chemistry have been used to provide insights into the scale dependencies of streamflow generation processes in small catchments. However, these scale dependencies have not been thoroughly investigated at large watershed scales (defined as drainage areas greater than 1000 km2). Quantifying these scale dependencies is critical to understanding how large watersheds will respond to future perturbations; e.g., the long‐term streamflow response to climate change and/or changes in land‐cover and land‐use. Here we investigate the spatial and temporal scaling relationships of all dominant streamflow generation processes in a large alpine watershed in the southern Rocky Mountains of Colorado. Observations in the watershed indicate that dominant streamflow processes are spatially and temporally variable. The relative strengths of dominant streamflow mechanisms vary as a function of internal watershed structure (i.e., spatial variability in topographic relief, soil development, groundwater flowpath development, and stream network structure) and external forcing such as timing and character of precipitation. This behavior coupled with previous observations that streamflow from the watershed contained a significant component of basin‐scale groundwater, suggests that similar large watersheds may have internal buffering, at least initially, against rapid change.