Treesearch

Local plant community assembly is influenced by a series of filters that affect the recruitment and establishment of species. These filters include regional factors that limit seeds of any given species from reaching a local site as well as local interactions such as post-dispersal seed predation and disturbance, which dictate what species actually establish. How these filters interact to influence recruitment into local assemblages, and whether they act differentially on individual species based on traits such as seed size or their provenance (i.e. native vs. exotic), has not been well...

The U.S. Forest Service includes three main branches: National Forest Systems, Research and Development, and State and Private Forestry. Herein, we focus on National Forest Systems and Research and Development. National Forest Systems is the management branch of the agency, and its charge is to administer national forests and grasslands throughout the United States. A number of laws, statutes, and policies guide and direct how forests should be managed, including provisions for considering and applying the best available science when planning and executing management actions. The Research...

The flow of woody biomass to end users is determined by economic factors, especially the amount available across a landscape and delivery costs of bioenergy facilities. The objective of this study develop methodology to quantify landscape-level stocks and potential biomass flows using the currently available spatial database road network analysis tool. We applied this methodology to a landscape of approximately 15 million acres around city Roseburg in southwestern Oregon. The analysis allows us produce isocost contour maps that display supply areas delineated by specific cost thresholds,...

Forest and mill residues are a promising source of biomass feedstock for the production of bioenergy, biofuels and bioproducts. However, high costs of transportation and handling of feedstock often make utilization of forest residues, such as logging slash, financially unviable. As a result, these materials are often considered waste and left on site to decompose or pile-burned to reduce wildfire risk and open space for regeneration. As an alternative, in-wood processing of forest biomass with a small scale, mobile biomass conversion unit that can be deployed near the source of feedstock...

Given the projected threat that climate change poses to biodiversity, the need for proactive response efforts is clear. However, integrating uncertain climate change information into conservation planning is challenging, and more explicit guidance is needed. To this end, this article provides a specific example of how a risk-based approach can be used to incorporate a species' response to climate into conservation decisions. This is shown by taking advantage of species' response (i.e., impact) models that have been developed for a well-studied bird species of conservation concern. Specifica...

The introduced tree species Spathodea campanulata (Bignoniaceae) forms novel forests in Puerto Rico, these having emerged after the abandonment of fields in the mid-20th century and resulting in forests with a new species composition. We assessed bryophyte species richness in these novel forests and sought correlations with geological substrate, past land use, forest edge and patch area, forest structure, elevation, microhabitat diversity, tree species richness, and microclimatic conditions. Transects were established (edge and forest interior) in nine moist forest patches dominated by...

Anthropogenic S emissions in the Athabasca oil sands region (AOSR) in Alberta, Canada, affect SO4 deposition in close vicinity of industrial emitters. Between May 2008 and May 2009, SO4-S deposition was monitored using open field bulk collectors at 15 sites and throughfall collectors at 14 sites at distances between 3 and 113 km from one of the major emission stacks in the AOSR. At forested plots >90 km from the operations, SO4 deposition was ~1.4 kg SO4-S ha-1 yr-1 for bulk deposition and ~3.3 kg SO4-S ha-1 yr-1 for throughfall deposition. Throughfall SO4 deposition rates in the AOSR...

Both the biodiversity and the landscapes of the Caribbean have been greatly modified as a consequence of human activity. In this essay we provide an overview of the natural landscapes and biodiversity of the Caribbean and discuss how human activity has affected both. Our Caribbean geographic focus is on the insular Caribbean and the biodiversity focus is on the flora, forests, and built up land. Recent land cover changes from agricultural to urban cover have allowed for the proliferation of novel forests, where introduced plant species have naturalized and play important ecological roles...

In 2012, the nation experienced one of the largest wildland fire seasons in US history. More than 9 million acres burned, overwhelming fire-suppression budgets, burning homes and other structures, and taking the lives of both firefighters and civilians around the country. In Montana alone, 1.1 million acres burned, resulting in the largest wildfire year since 1910. As changing climate, insect infestations, exurban development, and other external stresses impact the nation's forests and other wildlands, many anticipate we could experience even longer and more severe fire seasons, and that...