Treesearch

Forest vegetation mapping that integrates forest inventory data with multispectral remote sensing data provides valuable geospatial products for public land management agencies, but resource managers may require rapid updating of maps as new imagery becomes available (updating) or retrospective mapping for times prior to forest inventory plot measurement (hindcasting). While forest attribute mapping using Landsat multispectral imagery is common, the accuracy of applying models outside of reference epoch to support long-term forest monitoring is not normally quantified. We examine whether a...

In North America, a comparatively small number of Fraxinus (ash) cultivars were planted in large numbers in both urban and rural environments across the entire range of Fraxinus pennsylvanica Marsh (green ash) over the last 80 years. Undetected cultivar gene flow, if extensive, could significantly lower genetic diversity within populations, suppress differentiation between populations, generate interspecific admixture not driven by long-standing natural processes, and affect the impact of abiotic and biotic threats. In this investigation we generated the first range-wide genetic assessment...

Forests worldwide are experiencing increasingly intense biotic disturbances; however, assessing impacts of these disturbances is challenging due to the diverse range of organisms involved and the complex interactions among them. This particularly applies to invasive species, which can greatly alter ecological processes in their invaded territories. Here we focus on the pine wood nematode (PWN, Bursaphelenchus xylophilus), an invasive pathogen that has caused extensive mortality of pines in East Asia and more recently has invaded southern Europe. It is expected to expand its range into...

Freshwater turtles are important components of wetland ecosystems, but few studies have assessed the quality of created and restored wetlands for turtles. We determined whether habitat characteristics and abundance, body condition, adult sex ratio, and mean adult size of two turtle species, Painted Turtles (Chrysemys picta) and Snapping Turtles (Chelydra serpentina), differed between 16 restored and 16 reference wetlands in West Virginia, USA, and quantified the influence of habitat characteristics on abundance and body condition. At each wetland, we measured habitat characteristics and...

We quantified temporal dynamics of wood storage, input, and transport over a 24-year period in adjacent old-growth and second-growth forested reaches in Mack Creek, a third-order stream in the Cascade Range of Oregon. The standing stocks of large wood in the old-growth reach exceeded those at the second-growth reach by more than double the number of wood pieces and triple the wood volume. Annual inputs of large wood were highly variable. Wood numbers delivered into the old-growth reach were 3× higher and wood volume 10× greater than in the second-growth reach. The movement of number and...

1. Naturally treeless ecosystems are being replaced by native and non-native trees worldwide, often through deliberate afforestation using forestry tree species. By introducing species having novel traits, such as relatively rapid growth, many afforestation efforts also produce numerous changes in ecosystems, at the landscape scale.2. Trees are considered critical for climate change mitigation; indeed, many current carbon sequestration strategies rely on trees. Planting trees or allowing trees to naturally colonize through range expansions can be seen as an ideal way to increase atmospheric...

Modeling of moisture transfer in porous materials is typically partitioned into liquid transport and vapor diffusion. Coefficients for liquid transport are often derived from laboratory measurements of water absorption by partial immersion. Although the assumption that capillary liquid transport is dominant while vapor diffusion is negligible is a reasonable assumption for mineral-based materials, recent work indicates that it is not representative of water absorption in wood across the grain. This article builds on earlier work and develops an improved engineering model for liquid water...

Water vapor sorption is a fundamental property of cellulosic materials. Numerous theoretical and empirical models have been developed to describe the relationship between water activity, temperature, and equilibrium moisture content (EMC). However, a meaningful connection between model parameters and thermodynamic properties related to the sorption process is often lacking. In cases where models yield thermodynamic properties, such as through use of the Clausius-Clapeyron equation, these are limited to temperatures where the ideal gas equation is applicable. In this paper we advance a...

This study aimed to investigate the intrinsic efficiency of renewable alcohols, applied under autocatalytic conditions, for removing lignin from aspen and hot-water-extracted aspen while substantially preserving the lignin structure so as to facilitate various valorization strategies. Ethylene glycol (EG), propylene glycol (PG), 1,4-butanediol (BDO), ethanol (EtOH), an tetrahydrofurfuryl alcohol (THFA) were evaluated based on their lignin solubilization ability, expressed as the relative energy difference (RED) following the principles of the Hansen solubility theory. The findings indicate...