Treesearch

This assessment provides information on the conditions of riparian and groundwater-dependent ecosystems in the Humboldt-Toiyabe National Forest (HTNF). We summarized dominant riparian community types and described riparian fish and wildlife habitat. We used peer-reviewed literature, data from the National Forest and other partners, and site visits to inventory and map the distribution of riparian and groundwater-dependent ecosystems, as well as to evaluate the status of five key ecosystem characteristics: (1) surface water and groundwater fluctuations, (2) water quality, (3) channel and...

Spatially continuous patterns of genetic differentiation, which are common in nature, are often poorly described by existing population genetic theory or methods that assume either panmixia or discrete, clearly definable populations. There is therefore a need for statistical approaches in population genetics that can accommodate continuous geographic structure, and that ideally use georeferenced individuals as the unit of analysis, rather than populations or subpopulations. In addition, researchers are often interested in describing the diversity of a population distributed continuously in...

Broadly speaking, prediction of the negative impacts of prescribed fire on air quality is limited by gaps in our understanding of the underlying fire, fuels, and atmospheric processes. These knowledge gaps hinder our ability to accurately predict smoke concentration distributions, leading to unintended smoke intrusions into nearby communities and subsequent threats to public health and safety. In this study, numerical simulations are performed using the Flexible Particle Weather Research and Forecasting (FLEXPART-WRF) Model, a Lagrangian particle dispersion model, with particle motion...

Wood is the water conducting tissue of tree stems. Like most angiosperm trees, poplar wood contains water-conducting vessel elements whose functional properties affect water transport and growth rates, as well as susceptibility to embolism and hydraulic failure during water stress and drought. Here we used a unique hybrid poplar pedigree carrying genomically characterized chromosomal insertions and deletions to undertake a systems genomics analysis of vessel traits. We assayed gene expression in wood forming tissues from clonal replicates of genotypes covering dosage quantitative trait...

Aquatic fungi drive important ecosystem processes, which may be affected by anthropogenic stressors, including changes in water quality. However, due to the great diversity of aquatic fungi, our understanding of the relationships among water quality variables, fungal community composition, and ecosystem function remains incomplete. Here, we show that aquatic fungal community structure and functional diversity correlate strongly with water quality. We used a multi-marker survey of environmental DNA and long-term water quality data to survey 17 stream, pond, and tidal creek sites within a...

Wildfire is an important natural disturbance agent in Canadian forests, but it has also caused significant economic damage nationwide. Spatial fire growth models have emerged as important tools for representing wildfire dynamics across diverse landscapes, enabling the mapping of key wildfire hazard metrics such as location-specific burn probabilities or likelihoods of fire ignition. While these summary metrics have gained popularity, they often fall short in capturing the directional spread of wildfires and their potential spread distances. The metrics depicting the directional spread of...

Mangroves’ ability to store carbon (C) has long been recognized, but little is known about whether planted mangroves can store C as efficiently as naturally established (i.e., intact) stands and in which time frame. Through Bayesian logistic models compiled from 40 years of data and built from 684 planted mangrove stands worldwide, we found that biomass C stock culminated at 71 to 73% to that of intact stands ~20 years after planting. Furthermore, prioritizing mixed-species planting including Rhizophoraspp. would maximize C accumulation within the biomass compared to monospecific planting....

Objective: New characterized carbohydrate-active enzymes are needed for use as tools to discriminate complex carbohydrate structural features. Fungal glycoside hydrolase family 3 (GH3) β-xylosidases have been shown to be useful for the structural elucidation of glucuronic acid (GlcA) and arabinofuranose (Araf) substituted oligoxylosides. A homolog of these GH3 fungal enzymes from the bacterium Segatella baroniae (basonym Prevotella bryantii), Xyl3C, has been previously characterized, but those studies did not address important functional specificity features. In an interest to utilize this...

Fire experiments were conducted to observe the effect of varying amounts of exposed timber wall and ceiling assemblies in a standard room-corner fire test. The standard test, NFPA 286 (Fire Tests for Evaluating Contribution of Wall and Ceiling Interior Finish to Room Fire Growth) is based on a room with a door opening at the front and a gas burner located against a back corner. Pass or fail criteria for flashover are provided for the test, with the test lasting up to a maximum of 15 min. Three experiments were conducted that comply with the 2021 International Building Code for amount of...

Pyrolysis of wood involves the thermal degradation of the wood polymers and the formation of char. Understanding how char forms, particularly, in terms of the nano-structural changes that take place during pyrolysis will inform fire models to ensure fire safety in timber structures. Here, small- and wide-angle x-ray scattering (SAXS/WAXS) based tomography were used to study how thermal degradation changes wood nanostructure across the pyrolysis zone in Douglas-fir. The changes in the aggregation of cellulose elementary fibrils (via SAXS) as well as changes in the cellulose crystallinity...