Treesearch

Background. Fuel treatments are increasingly used to mitigate wildfire risks. Aims. Proposing a novel, scalable and transferable methodology, this study investigates which treatment is (more) effective at a regional scale. Methods. This research evaluates the effectiveness of fuel treatments in California forests using the Fuel Treatment Effectiveness Monitoring (FTEM) database, which provides a binary (yes/no) assessment of treatment efficacy based on a structured subjective evaluation process. Proposed methodology enables scaling up site-specific treatment outcomes to the regional level....

A timber frame with mass ply lam (MPL) beams and columns and a timber buckling restrained brace (TBRB) was subjected to cyclic loads according to the AISC qualification procedure for conventional buckling restrained braces (BRB). The TBRBs met the requirements for qualification of conventional BRBs; the steel core reached a maximum strain of 3.l% in both tension and compression and the braced frame reached a maximum drift ratio of 4.5%. A numerical OpenSees model of a single-story timber frame with a TBRB was built and validated by TBRB component tests and MPL beam-column joint tests with...

Tropical forests are a dominant regulator of the global carbon cycle, exchanging more carbon dioxide with the atmosphere than any other terrestrial biome. Climate models predict unprecedented climatic warming in tropical regions in the coming decades; however, in situ field warming studies are severely lacking in tropical forests. Here we present results from an in situ warming experiment in Puerto Rico, where soil respiration responses to +4 oC warming were assessed half-hourly for a year. Soil respiration rates were 42- 204% higher in warmed relative to ambient plots, representing some...

General understanding of disease epiphytotics caused by introduced agents (pathogens) in forest systems, as well as the ability to assess risk of future introductions within a process-barrier framework of biological invasion, are impeded by a lack of systematically compiled information on origins and functional traits of pathogens that have become established outside their range. To address these gaps, substantially update previous registries, and provide critical biosecurity information, we assembled a list of established forest phytopathogens that are present, but not thought to be...

The use of nested plot sizes in forest inventories that encounter a wide range of conditions is relatively common. In straightforward situations, data from the different nested plot sizes are usually combined to create a single plot observation for estimation purposes. However, circumstances may occur where nested plot size estimates are obtained separately and subsequently combined via addition to obtain the final result. In these cases, covariances among the nested plots must be considered in the calculation of estimator variance. However, there are several potential approaches that...

Background: Individual tree attributes such as volume, biomass and carbon mass are widely known to be highly correlated. As these attributes are typically predicted from statistical models, frameworks that provide compatible relationships among these attributes are usually preferred over approaches that provide independent predictions. However, the propagation of model error can be a concern as this compatibility often relies on predictions for one attribute providing the basis for other attributes. In this study, a compatible tree volume, biomass, and carbon prediction system was evaluated...

The Log Recovery Analysis Tool (LORCAT) was developed to enable hardwood sawmill personnel, researchers, and other individuals interested in creating lumber and by-products from logs to examine the impacts of and the relationships among various factors that influence lumber recovery in hardwood mills. LORCAT is a spreadsheet-based tool that was developed for use with either Excel (Microsoft Inc., Redmond, Washington, USA) or LibreOffice (The Document Foundation, Berlin, Germany) spreadsheet applications. LORCAT allows users to interactively view the results from a single log or view trends...

Mechanistic habitat assessment models have long been used for stream fish, especially drift-feeding salmonids. Most of these models assess habitat value as the rate of net energy intake (growth) obtained by a fish feeding in a habitat unit. However, the fitness value of habitat and the willingness of fish to occupy it also depend on predation risk: habitat is not valuable if it offers high growth but also high risk. Methods for modeling how predation risk varies with characteristics of habitat and fish are much less developed than those for modeling net energy intake. We present approaches...

In plant cell walls, lignin, cellulose, and the hemicelluloses form intricate three-dimensional structures. Owing to its complexity, lignin often acts as a bottleneck for the efficient utilization of polysaccharide components as biochemicals and functional materials. A promising approach to mitigate and/or overcome lignin recalcitrance is the qualitative and quantitative modification of lignin by genetic engineering. Feruloyl-CoA 6′-hydroxylase (F6′H1) is a 2-oxoglutaratedependent dioxygenase that catalyzes the conversion of feruloyl-CoA, one of the intermediates of the lignin biosynthetic...

Chirpine (Pinus roxburghii), also known as longleaf Indian pine, is the most tapped pine species in several Asian countries, including Nepal, for its high resin yield. Resin tapping in Chirpine trees has been a longstanding practice in mid-hills of Nepal for the last several decades. This study aimed to evaluate the social impacts of resin tapping from Chirpine forests on the rural socio-ecological dynamics of Nepal’s mid-hills. Using a representative sample of 302 forest users from 20 community forest user groups in three far-western districts, we applied the structural equation modeling...