Treesearch

Rock glaciers are important headwater landforms that play a key role in alpine hydrology. North American rock glaciers are estimated to contain the third largest water volume equivalent globally, and over 3800 rock glaciers have been mapped in Colorado alone. However, these features are often overlooked in alpine water budgets. In this study, we present initial results using geophysical, hydrochemical, and repeat structure from motion data to investigate the ice presence, downslope movement, and influence on stream chemistry of the Lake Agnes rock glacier in the northern Front Range,...

Litter decomposition is an important ecosystem process and global carbon flux that has been shown to be controlled by climate, litter quality, and microbial communities. Process-based ecosystem models are used to predict responses of litter decomposition to climate change. While these models represent climate and litter quality effects on litter decomposition, they have yet to integrate empirical microbial community data into their parameterizations for predicting litter decomposition. To fill this gap, our research used a comprehensive leaf litterbag decomposition experiment at 10...

Southern U.S. forests are essential for carbon storage and timber production but are increasingly impacted by natural disturbances, highlighting the need to understand their dynamics and recovery. Canopy cover is a key indicator of forest health and resilience. Advances in remote sensing, such as NASA’s GEDI spaceborne LiDAR, enable more precise mapping of canopy cover. Although GEDI provides accurate data, its limited spatial coverage restricts large-scale assessments. To address this, we combined GEDI with Synthetic Aperture Radar (SAR), and optical imagery (Sentinel-1 GRD and Landsat–...

Post-wildfire erosion to downstream surface waters can deteriorate water quality to levels that can create challenges for aquatic life and drinking water treatment. Polymeric additives, xanthan gum (XG) and polyacrylamide (PAM), have been demonstrated to be effective for controlling erosion in the presence of hydrophilic ash. However, with repeated rainfall applications, some of the applied XG and PAM may mobilize with the runoff and enter surface waters, which may pose water quality concerns. In this study, indoor rainfall simulation experiments were performed on plots containing wildfire-...

Flow pathways on unpaved forest roads are critical determinants of surface runoff and sediment transport. These flow pathways can be largely altered through road deformation caused by heavy traffic, with one of the most common types of deformation being ruts. Historically, rut development has been studied using cross-sectional analyses. More recently, remote sensing techniques, such as structure-from- motion (SfM) or terrestrial LiDAR scanning (TLS), have demonstrated their utility in mapping ruts on forest roads. However, applications of these data are limited, especially with respect to...

As wildfires intensify across the western United States, understanding long-term ecosystem recovery is increasingly critical. Post-fire soil amendments, such as woody mulch or biochar, are commonly used to stabilize soils and promote vegetation recovery, yet their effects on plant functional strategies and plant–microbe interactions remain poorly understood. Thirteen years after a high-severity wildfire in Colorado, we evaluated the impacts of these treatments on soil properties, microbial communities, and plant functional traits, including plant height, specific leaf area (SLA), and leaf...

Anthropogenic pressures have altered fire regimes across the western United States. These altered fire regimes, and the megafires they often produce, threaten ecologically and economically critical ecosystems and biodiversity across this region. Oak woodland savannas may be particularly sensitive to altered fire regimes, but there remains a significant gap in our understanding of how different characteristics of wildfire impact these ecosystems and the wildlife species that reside within them. In this study, we used an occupancy modeling framework to investigate how fire severity and...

Diapause regulates seasonal insect life cycles and may be highly variable within and among populations due to genetic and environmental variability. Both types of variation may influence how populations respond plastically or evolutionarily to changing climates. We assessed diapause variability in spruce beetle Dendroctonus rufipennis Kirby (Coleoptera: Curculionidae, Scolytinae), a major forest pest whose life cycle timing is regulated by both prepupal and adult diapauses. Using mating studies and ovary dissections, we tested for variability in adult diapause within and between collection...

Headwater streams are abundant in mountain landscapes and where municipal watersheds occur on public lands; they co-occur with road networks open to off-highway vehicle (OHV) use. Despite well-known, deleterious interactions of roads and streams, few studies have empirically examined the biophysical impacts of OHV use where backcountry roads enter streams at open-water crossings. We present a case study using a controlled design where we quantified OHV road impacts in a Rocky Mountain stream and evaluated the restoration efficacy by examining aquatic biota and habitat before and after...

Habitat selection and movement are key mechanisms by which animals can respond to and potentially cope with highly variable environmental conditions. Optimal responses likely vary, however, depending on the severity and scope of conditions. We tested this hypothesis using a facultative migrant species, the Great Gray Owl (Strix nebulosa), which exhibits high inter-and intra-individual variation in the timing, direction, and distance of winter movements. Specifically, we evaluated whether episodic, spatiotemporally variable “locked-pasture” snow conditions, which restrict access to subnivean...