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Prescribed fire can be used to return wild lands to their natural fire cycle, control invasive weeds, and reduce fuel loads, but there are gaps in the understanding of post-disturbance responses of vegetation and hydrology. The impact of a prescribed fire and subsequent aspen cutting on evapotranspiration (ET) and streamflow was assessed for the Upper Sheep Creek catchment, a 26-ha headwater catchment dominated by low sagebrush, mountain big sagebrush, and aspen within the Reynolds Creek Experimental Watershed. The 2007 prescribed fire consumed 100% of the mountain big sagebrush and approximately 21% of the low sagebrush. The aspen, which were mostly untouched by the fire, were cut in the fall of 2008. Post-disturbance ET and vegetation recovery were related to the loss of rooting depth. ET recovered within 2 years on the low sagebrush area with limited rooting depth, while that on the deeper-rooted mountain big sagebrush area took 4 years to recover. ET from the aspen trees, which can sprout from existing roots, recovered within 2 years. The influence of vegetation disturbance on streamflow was assessed using both empirical time trend analysis and process-based modelling. Although both approaches suggested approximately a 20% increase in streamflow during the 6 years post-disturbance, results from the empirical time trend analysis were marginally significant ( p = 0·055), while those from the process-based modelling were not statistically significant. Marginal streamflow response can be attributed to rapid post-disturbance recovery of the aspen where most of the streamflow originates. Published 2016. This article is a U.S. Government work and is in the public domain in the USA [ABSTRACT FROM AUTHOR]

The article discusses the effect of simulated soil water storage on streamflow generation in the mountainous snowmelt surroundings in Idaho. The author claims that soil processes affect the timing and amount of streamflow produced from snowmelt in the western U.S. Meanwhile, the article looked into the use of soil water balance modeling approach to integrate the impact of soil processes, particularly the soil water storage and the timing and amount of snowmelt generated streamflow. Moreover, the distributed simulations over the watershed for the same two years shows that streamflow movements are closely related to the overall watershed soil water storage capacity that serves as a threshold.

Several methods for quantifying ET for two rangeland vegetation types over an 8-yr study period agreed well with each other. Methods included eddy covariance systems, soil water storage loss measured by time domain reflectometry and neutron probe, and model simulation. Evapotranspiration (ET) was quantified for two rangeland vegetation types, aspen and sagebrush-grassland, over an 8-yr study period by comparing the following approaches for estimating ET: eddy covariance systems (EC, available for only 6 yr); soil water storage loss measured by time domain reflectometry (TDR) and neutron probe; and model simulation. The research site, the Upper Sheep Creek catchment in the Reynolds Creek Experimental Watershed, is part of a study on the effects of prescribed fire and vegetation removal. Estimates of seasonal ET for the aspen using EC with the turbulent fluxes adjusted to force energy balance closure, a 180-cm TDR soil profile, two 225-cm neutron access tubes, and the Simultaneous Heat and Water (SHAW) model agreed well with each other. If the two neutron probes were averaged, the RMSD of all approaches over the 6 yr was within 8% of the average. For the sagebrush-grassland, a 120-cm TDR profile underestimated seasonal ET for all years except the year immediately following the prescribed fire, when rooting depth likely had not recovered. A 195-cm neutron probe access tube located within 30 m of the stream underestimated ET for every year except when there was no streamflow, suggesting that lateral flow may have biased the results for this tube. A comparison of the other methods (EC flux adjusted to force energy balance closure, soil water loss measured from a 225-cm neutron access tube, and SHAW model simulation) agreed within 3% during the 6 yr with EC measurements at that site. [ABSTRACT FROM AUTHOR]