Publications by authors named "Roy C Sidle"

Mountain regions of Central Asia are experiencing strong influences from climate change, with significant reductions in snow cover and glacial reserves. A comprehensive assessment of the potential consequences under the worst-case climate scenario is vital for adaptation measures throughout the region. Water balance analysis in the Naryn River basin was conducted for the baseline period of 1981-2000 including potential changes under the worst-case SSP5-8.

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Overland transport of fecal bacteria in water and their resuspension from bed sediments are important transport mechanisms that help explain the transport of enteric pathogens in watersheds. In this study, multiyear monitoring along with regression relationships between sediment and fecal indicator bacteria (FIB) were used to investigate annual loading in the South Fork Broad River watershed, located in northeastern Georgia, USA. Suspended transport was the dominant transport mechanism contributing to in-stream total annual loads for sediment (81.

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We assessed spatial distribution of infiltration capacity under forest canopies to simulate runoff processes in a steep small catchment in Japan. High resolution LiDAR data were used to assess light availability to understory vegetation, which in turn was converted into an understory vegetation cover ratio. Spatially distributed infiltration capacities based on data from field rainfall-runoff experiments were incorporated into the TopoTube model using a relationship between infiltration capacity and vegetation cover.

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Background And Aims: Root mechanical traits, including tensile strength (Tr), tensile strain (εr) and modulus of elasticity (Er), are key functional traits that help characterize plant anchorage and the physical contribution of vegetation to landslides and erosion. The variability in these traits is high among tree fine roots and is poorly understood. Here, we explore the variation in root mechanical traits as well as their underlying links with morphological (diameter), architectural (topological order) and anatomical (stele and cortex sizes) traits.

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Major earthquakes cause widespread environmental and socioeconomic disruptions that persist for decades. Extensive ground disturbances that occurred during the shallow-focus Kumamoto earthquakes will affect future sustainability of ecosystem services west of Aso volcano. Numbers of earthquake-initiated landslides per unit area were higher in grasslands than forests, likely owing to greater root reinforcement of trees, and mostly initiated on ridgelines and/or convex/planar hillslopes.

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Bed sediments of streams and rivers may store high concentrations of fecal indicator bacteria (FIB) and pathogens. Due to resuspension events, these contaminants can be mobilized into the water column and affect overall water quality. Other bacterial indicators such as microbial source tracking (MST) markers, developed to determine potential sources of fecal contamination, can also be resuspended from bed sediments.

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Although the concept of ecosystem sustainability has a long-term focus, it is often viewed from a static system perspective. Because most ecosystems are dynamic, we explore sustainability assessments from three additional perspectives: resilient systems; systems where tipping points occur; and systems subject to episodic resetting. Whereas foundations of ecosystem resilience originated in ecology, recent discussions have focused on geophysical attributes, and it is recognized that dynamic system components may not return to their former state following perturbations.

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Although elephants may exert various impacts on the environment, no data are available on the effects of elephant trails on runoff, soil erosion, and sediment transport to streams during storms. We monitored water and sediment fluxes from an elephant trail in northern Thailand during seven monsoon storms representing a wide range of rainfall energies. Runoff varied from trivial amounts to 353 mm and increased rapidly in tandem with expanding contributing areas once a threshold of wetting occurred.

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We determined the extent that a riparian buffer reduces stream suspended sediment concentrations by filtering road runoff during 18 rain events in a 2.5-ha, multi-use watershed in northern Thailand. The dominant buffer species was the perennial sedge Fimbristylis aphylla Zoll.

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Resource managers require objective methodologies to optimize decisions related to forest road deactivation and other aspects of road management, especially in steep terrain, where road-related slope failures inflict extensive environmental damage. Decision analysis represents a systematic framework that clearly identifies real options and critical decision points. This framework links current decisions with expected future outcomes and provides advantages such as a common currency to systematically explore the liability consequences of limited budget expenditures to road deactivation and other road-related activities.

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