Rainfall interception by mountain big sagebrush (Artemisia tridentata ssp. vaseyana)

Abstract

Significant precipitation losses can occur due to interception, the process in which rain or snow is captured by plant canopies. In the sagebrush biome, projected shifts in precipitation patterns due to climate change may complicate the already scarce resources of water. This research reviewed existing literature on rainfall redistribution in shrublands and used small-plot rainfall simulation experiments to quantify interception values for mountain big sagebrush (Artemisia tridentata spp. vaseyana). The goals of this thesis were to 1) quantify rainfall interception by mountain big sagebrush across a range of cover values, 2) identify shrub measurements with utility in scaling interception to the community level, and 3) investigate the larger context of arid shrub precipitation partitioning. Sagebrush interception averaged 18.5 ± 12.4%. Interception rates were highest for the high cover class and lowest for the low cover class, indicating that effective precipitation may be significantly reduced under mature, dense stands of sagebrush.