Treesearch

Acetylation is one of the most common types of wood modifcation and is commercially available throughout the world. Many studies have shown that acetylated wood is decay resistant at high levels of acetylation. Despite its widespread use, the mechanism by which acetylation prevents decay is still not fully understood. It is well known that at a given water activity, acetylation reduces the equilibrium moisture content of the wood cell wall. Furthermore, linear relationships have been found between the acetylation weight percent gain (WPG), wood moisture content, and the amount of mass loss...

Salt damage in wood can be recognized by its stringy appearance and is frequently observed in wood used in maritime structures and buildings built near the ocean. Whereas salt-damaged wood is common, little is known about the mechanism by which salt water alters the wood structure. There is no information on the effects of salt damage on the mechanical properties of wood. In this study, a laboratory method for creating salt damage in other porous materials was applied to wood. Wood pillars were placed in a reservoir of 5 M NaCl and exposed to a 40% RH environment. Capillary action pulled...

Forests provide the most stable and highest quality water supplies among all land uses. The Southern United States is heavily forested, and most of the forests are owned and managed by State and private entities, thus it is critical to understand the role of forest lands in providing water across the region, the fastest growing in the Nation. We quantified surface water supply originating on State and private forest (SPF) lands in the 13 Southern States at the 12-digit Hydrologic Unit Code watershed scale, using the Water Supply Stress Index (WaSSI) hydrologic model. Water originating on...

Abstract1. Mechanisms driving patterns of occurrence and co-occurrence among NorthAmerican freshwater fishes are poorly understood. In particular, the influence ofbiotic interactions on coexistence among stream reaches and their effects on regionalspecies distribution patterns is not well understood for congeneric headwaterfishes.2. Occupancy models provide a useful framework for examining patterns of co-occurrencewhile also accounting for imperfect detection. Occupancy models maybe extended to test for evidence that a dominant species influences the occurrenceof a subordinate species and...

Fire in tropical forests increases tree mortality, degrades forest structure, and reduces carbon stocks. Currently, there are large gaps in understanding how fire affects understory forest structure and composition, interactions with fire recurrence, and longterm impacts. Understanding these changes is critical to evaluate the present and future response of tropical forests to fire. We studied post-fire changes in understory regeneration in forests in Mato Grosso State, southern Amazonia, Brazil, aiming to answer the following questions: (i) does forest structure (basal area) and tree...

A new species of Furculanurida is described and illustrated. Furculanurida bistribus sp. nov. differs from other species of the genus by the presence of three eyes, three setae on the dens, and the white and purple coloration pattern. A key for identification of the world species of the genus is included.