| The estimation of mean transit times (MTTs) is regarded as a powerful descriptor of catchment systems since it provides broad information about hydrological mixing and storage processes in a single encompassing measurement. In this study, convolution lumped modeling was incorporated into the R programming language. Approximately 3.5 years of precipitation and streamflow water isotope signatures were used to estimate transit times across six Precambrian Shield catchments in the Muskoka-Haliburton region of south-central Ontario. The main objective of this study was to explore the main physical controls governing catchment-scale transit times by investigating relationships with light detection and ranging (LiDAR)-based landscape metrics. The MTTs were best correlated to topographic metrics such as flow path gradient and the ratio of flow path length to gradient (i.e. L/G index). These findings support the notion that within shallow-soil catchments in the Precambrian Shield region, it is topography, especially gradient-driven metrics, which is most meaningful in dictating catchment-scale water storage and movement. |
