Treesearch

Submerged and emergent wetland plant communities are evaluated for their response to global climate change (GCC), focusing on seagrasses, submerged freshwater plants, tidal marsh plants, freshwater marsh plants and mangroves. Similarities and differences are assessed in plant community responses to temperature increase, CO2increase, greater UV-B exposure, sea level rise and other expected environmental alterations associated with GCC. Responses to most climate change variables are more similar within submerged plant communities, marine or freshwater, than between submerged vs. emergent...

Tree-killing bark beetles are major disturbance agents affecting coniferous forest ecosystems. The role of environmental conditions on driving beetle outbreaks is becoming increasingly important as global climatic change alters environmental factors, such as drought stress, that, in turn, govern tree resistance. Furthermore, dynamics between beetles and trees are highly nonlinear, due to complex aggregation behaviors exhibited by beetles attacking trees. Models have a role to play in helping unravel the effects of variable tree resistance and beetle aggregation on bark beetle outbreaks. In...

MCFire is a computer program that simulates the occurrence and effects of wildfire on natural vegetation, as a submodel within the MC1 dynamic global vegetation model. This report is a technical description of the algorithms and parameter values used in MCFire, intended to encapsulate its design and features a higher level that is more conceptual than the level provided by the computer source code, so that programmers and users can better understand its features and limitations. Two primary sources of the MCFire algorithms are the National Fire-Danger Rating System and CONSUME 3.0. MC1...

We evaluate the outcomes and consequences of a decade-long restoration project in a Hawaiian lowland wet forest as they relate to long-term management actions. Our initial study was designed both to promote native biodiversity and to develop knowledge that would enable land management agencies to restore invaded forests. Our premise of success followed the prevalent perception that short-term management, such as removal of invasive species, ideally translates into long-term and sustainable restoration. We were therefore disappointed and perhaps discouraged in our results—little recovery of...

Recent changes in precipitation patterns and in the occurrence of extreme temperature and precipitation events have been documented in many forested regions of the United States (Ryan and Vose 2012). Changes in drought intensity and frequency have the potential to alter populations and impacts of tree-damaging forest insects and pathogens (Ayers and Lombardero 2000, Dale and others 2001, Weed and others 2013). Scientists, forest managers, and environmental policymakers need to better understand the role of drought in outbreaks of forest insects and diseases in order to anticipate the...

A one-dimensional vertical numerical model for coupled water flow and heat transport in soil and snow was modified to include all three phases of water: vapor, liquid, and ice. The top boundary condition in the model is driven by incoming precipitation and the surface energy balance. The model was applied to three different terrestrial systems: A warm desert bare lysimeter soil in Boulder City, NV; a cool mixed-grass rangeland soil near Laramie, WY; and a snow-dominated mountainous forest soil about 50 km west of Laramie, WY. Comparison of measured and calculated soil water contents with...

This annotated bibliography contains all citations that we could find on tree voles (Arborimus longicaudus, A. pomo) and white-footed voles (A. albipes), including many unpublished sources in museum archives, court proceedings, and agency documents. Some documents not readily available in published form or museum archives are available upon request from the compilers.

Apparent US hardwood lumber consumption (developed from production, import, and export data) was contrasted with estimated consumption based on employment data and lumber utilization coefficients. The two methods of measuring domestic consumption provided similar results, but the use of employment data allowed for a comparison of appearance lumber vs industrial lumber use. Consumption of both appearance and industrial lumber increased between 1991 and 2000 as imported lumber augmented domestic lumber production. Exports increased during the 1990s but at a lower rate than domestic consumptio...

Forest disturbances are increasing in extent and intensity, annually altering the structure and function of affected systems across millions of acres. Land managers need rapid assessment tools that can be used to characterize disturbance events across space and to meet forest planning needs. Unlike vegetation management projects and wildfire events, which typically are well documented, there is often insufficient data on the extent and intensity of insect and disease outbreaks during periods between intensive inventories. This report describes a rapid assessment approach using normalized...

Black-backed woodpeckers (Picoides arcticus, [BBWO]) and American three-toed woodpeckers (P. dorsalis, [ATTW]) are uncommon inhabitants of conifer forests and are sympatric in some areas, including the Black Hills. Both species exhibit genetic characteristics associated with isolated populations, are species of special management concern, and for which data are lacking concerning populations and habitats. We developed resource selection models of forest vegetation within 500 m radius plots (78.5 ha) for BBWOs and ATTWs to provide forest managers with stand-level information to estimate how...