Treesearch

Fire has a profound, though paradoxical influence on landscapes of the southeastern U.S.; it simultaneously maintains native biodiversity and ecosystem processes but also threatens silvicultural resources and human landscapes. Furthermore, since the majority of the southern landscape is heavily influenced by human activities, contemporary fire regimes are human managed disturbances within extant firedependent ecosystems. Though there is considerable uncertainty in climate projections for the southeastern U.S., climate change will likely impact both prescribed fire and wildfire. In this...

As the focus of forest management on many public lands shifts away from timber production and extraction to habitat, restoration, and diversity-related objectives, it is important to understand the long-term effects that previous management activities have on structure and composition to better inform current management decisions. In this paper, we analyzed 40 years of growth data to quantify (1) the long-term response of yellow-poplar to thinning across an age and site quality gradient, and (2) the longevity of any growth response yellow-poplar may have to thinning throughout the southern...

Occluded, or intra-aggregate, soil organic matter (SOM) comprises a significant portion of the total C pool in forest soils and often has very long mean residence times (MRTs). However, occluded C characteristics vary widely among soils and the genesis and composition of the occluded organic matter pool are not well understood. This work sought to define the major controls on the composition and MRT of occluded SOM in western U.S. conifer forest soils with specific focus on the influence of soil mineral assemblage and aggregate stability.We sampled soils from a lithosequence of four parent...

The overall objective of this field study was to determine if Pinus nigra (Austrian Pine) could serve as a useful biomonitor to evaluate multi-year concentrations of total mercury (tHg) in vegetataion within southwesrern Pennsylvania. Austrian Pine has been widely planted as an ornamental and formerlay as a Christmas tree, and is now naturalized within the region. We collected needle samples annually during October 2004-2010 at 15-21 locations within a 5000-km2 study area. Because Austrian Pine trees typically retain needles for 3 years, we collected samples from 3 needle-age groups:...

1. Modelling the effects of environmental change on populations is a key challenge for ecologists, particularly as the pace of change increases. Currently, modelling efforts are limited by difficulties in establishing robust relationships between environmental drivers and population responses. 2. We developed an integrated capture–recapture state-space model to estimate the effects of two key environmental drivers (stream flow and temperature) on demographic rates (body growth, movement and survival) using a long-term (11 years), high-resolution (individually tagged, sampled seasonally)...

Direct effects of climate change on animal physiology, and indirect impacts from disruption of seasonal synchrony and breakdown of trophic interactions are particularly severe in Arctic and Alpine ecosystems. Unravelling biotic from abiotic drivers, however, remains challenging because high-resolution animal population data are often limited in space and time. Here, we show that variation in annual horn growth (an indirect proxy for individual performance) of 8043 male Alpine ibex (Capra ibex) over the past four decades is well synchronised among eight disjunct colonies in the eastern...

We describe a case of paravertebral abscess caused by a Phellinus sp. in a boy with chronic granulomatous disease. Sequencebased identification of this mold, a new agent of disease, suggests a close relation to Phellinus umbrinellus.

The Rocky Mountain Research Station’s 2014-2017 Strategic Business Plan presents the actions we will take to achieve our Vision and to meaningfully contribute to the needs of land managers, interested partners and the public as we support the mission of the Forest Service Research & Development (FS R&D) organization. The Business Plan serves as a communication tool between the Station‘s Leadership Team and our employees, the broader Forest Service community, and Forest Service colleagues.

A vision statement often describes a future state or condition to which one aspires. Such is not the case for the Station’s 2014-2017 Vision. While there is much we want to do to further enhance successful achievement of our Vision, we are well on our way.

The future health of ecosystems is arguably as dependent on urban sprawl as it is on human caused climatic warming. Urban sprawl strongly impacts the urban ecosystems it creates and the natural and agro-ecosystems that it displaces and fragments. Here, we project urban sprawl changes for the next 50 years for the fast-growing Southeast U.S. Previous studies have focused on modeling population density, but the urban extent is arguably as important as population density per se in terms of its ecological and conservation impacts. We develop simulations using the SLEUTH urban growth model that...