Treesearch

Variation in climate has been demonstrated to be a powerful driver of selection and local adaptation among plant populations. Variation in functional traits among populations can also be indicative of the drivers of local adaptation. However, it is not clear to what extent species exhibit consistent patterns of local adaptation as revealed by common, heritable trait–environment relationships among populations. To address this, we conducted a meta-analysis of common garden studies of grass populations to quantify the degree of heritability of several commonly measured functional traits, and...

Cellulose nanocrystal (CNCs)-reinforced poly(lactic acid) (PLA) nanocomposites were prepared using twin screw extrusion followed by injection molding. Masterbatch approach was used to achieve more efficient dispersion of CNCs in PLA matrix. Modified CNCs (b-CNCs) were prepared using benzoic acid as a nontoxic material through a green esterification method in a solvent-free technique. Transmission electron microscopy images did not exhibit significant differences in the structure of b-CNCs as compared with unmodified CNCs. However, a reduction of 6.6–15.5% in the aspect ratio of b-CNCs was...

This paper evaluates the potential of using 2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO)-oxidized cellulose nanoparticles (T-CNPs) as additives to tune the rheology of water-based acrylic resin (AR) coatings for flexible packaging applications. Three T-CNPs of T-CNF, T-MCC, and T-CNC were prepared from three starting cellulosic materials: cellulose nanofibers (CNF), microcrystalline cellulose (MCC), and cellulose nanocrystals (CNC), respectively. Their sizes ranged from 20 nm to 20 lmin diameter, and 234 nm to over 500 nm in length. The oxidation imparted carboxyl groups on the surfaces...

This study quantifies the cost of cellulosic sugar production using a fully-mechanical pretreatment process and fuel pellets as a co-product. The pretreatment reduces softwood forest harvest residuals to micron-sized amorphous particles. Energy consumption is minimized using a three-stage milling process. A techno-economic analysis was completed for a milling facility with saccharification and wood pellet manufacture. For the base case, concentrated sugar syrup can be produced for $0.496/kg of sugar. Sensitivity analyses were used to determine cost controlling variables, optimize the sugar...

LiDAR individual tree detection (ITD) is a promising tool for measuring forests at a scale that is meaningful ecologically and useful for forest managers. However, most ITD research evaluates methods over small homogeneous areas, while many forest managers work over large, complex landscapes. We investigated how ITD results varied across diverse structural conditions in California’s Sierra Nevada mixed-conifer forests and what this taught us about when and how to apply ITD. Our results suggest that it is advantageous to use ITD when it improves analysis interpretability, when measuring...

As the number, size, and complexity of ecological data sets have increased, narrative and interactive raw data visualizations have emerged as important tools for exploring and understanding these large data sets. As a demonstration, we developed three visualizations to communicate and explore passive integrated transponder tag data from two long-term field studies. We created three independent visualizations for the same data set, allowing separate entry points for users with different goals and experience levels. The first visualization uses a narrative approach to introduce users to the...

Organisms can modify their surrounding environment, but whether these changes are large enough to feed back and alter their evolutionary trajectories is not well understood, particularly in wild populations. Here we show that nutrient pulses from decomposing Atlantic salmon (Salmo salar) parents alter selection pressures on their offspring with important consequences for their phenotypic and genetic diversity. We found a strong survival advantage to larger eggs and faster juvenile metabolic rates in streams lacking carcasses but not in streams containing this parental nutrient input....

Bareroot hardwood seedlings are grown at both State and private nurseries across the 20-State U.S. Department of Agriculture (USDA), Forest Service, Northeastern Area. When propagated as bareroot seedlings, hardwood species such as oak, walnut, and black cherry are better suited for large-scale plantings due to size and cost factors. Here, we report on trends in the production of hardwoods and conifers at State and private nurseries in 2016 and on trends for four fine hardwood species from 2008 through 2016 at State nurseries: red oak (Quercus rubra L.), white oak (Quercus alba L.), black...

Catalytic graphitization of kraft lignin to nano-materials was investigated over four transitional metal catalysts (Ni, Cu, Fe, and Mo) through a thermal treatment process under an argon flow at 1000 °C. The catalytic thermal process was examined using thermal gravimetric analysis (TGA) and temperature-programmed decomposition (TPD) experiments. The crystal structure and morphology of the thermal-treated metal-lignin samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy....

Modifying bio-based degradable polymers such as polylactide (PLA) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) with non-degradable agents will compromise the 100% degradability of their resultant composites. This work developed a facile and solvent-free route in order to fabricate 100% bio-based and degradable ternary cellulose/PHBV/PLA composite materials. The effects of ball milling on the physicochemical properties of pulp cellulose fbers, and the ball-milled cellulose particles on the morphology and mechanical properties of PHBV/PLA blends, were investigated experimentally and...