Treesearch

The absence of some species from small habitat patches has long posed a challenge for conservationists, yet the underlying mechanisms that cause this "area-sensitivity" remain poorly understood. Capacity of a species to extend their activities into the surrounding matrix habitat represents one potential determinant of area-sensitivity. Species may be able to occupy smaller patches if they can utilize matrix habitat beyond patch boundaries, whereas area-sensitive species may be restricted to larger patches due to their inability to utilize the surrounding matrix. We investigated the...

Understanding the drivers of trait selection is critical for resolving community assembly processes. Here, we test the importance of environmental filtering and trait covariance for structuring the functional traits of understory herbaceous communities distributed along a natural environmental resource gradient that varied in soil moisture, temperature, and nitrogen availability, produced by different topographic positions in the southern Appalachian Mountains. To uncover potential differences in community-level trait responses to the resource gradient, we quantified the averages and...

Catchment mass balance demonstrates the role of hydrologic, pedogenic, and human influences on cycling of Ca, Al, Na, and Si, derived from plagioclase dissolution. As Na is little taken up by vegetation, does not accumulate in secondary soil pools, and is primarily in plagioclase, net Na output is a measure of plagioclase dissolution. Net Na flux is proportional to streamflow, illustrating hydrologic control of weathering. Rates of Ca, Al, and Si release from mineral dissolution are more difficult to evaluate as they are variably taken up by vegetation or stored in secondary soil pools....

The Anthropocene got off to a rough start. Looking back on the 2020s and 2030s, it felt as if the tapestry of ecological and social life was beginning to unravel, slowly at first but then picking up speed. Most of the "unravelling" was driven by climate disruption. World leaders had failed to act decisively -- or at all -- to curb greenhouse gas emissions and make the transition to sustainability earlier in the 21st century. As a result, atmospheric concentrations of greenhouse gases continued to climb and Earth’s average surface temperature edged steadily towards two degrees C (3.6...

Background: Evaluating relationships between avian populations and their habitat is important for understanding the biology of these species and for management decisions that improve the effectiveness of restoration practices. We investigated how habitat variation along a disturbance gradient affected the abundance of three insectivorous bird species, White-bellied Antbird (Myrmeciza longipes), Barred Antshrike (Thamnophilus doliatus), and Pale-breasted Spinetail (Synallaxis albescens) in a Neotropical dry forest remnant in central Colombia. Methods: The study area, which is located in...

The 2012 USDA Forest Service Planning rule requires that National Forests incorporate mitigation and adaptation strategies in response to climate change into their forest management plans. An underlying foundation of this work is knowing the distribution of aboveground biomass across the landscape. Climate change may put some areas with high biomass at greater risk for carbon emissions from wildfires, whereas other areas with reduced risk of wildfire may be preferred locations to manage for increased carbon storage.

To improve access and understanding of postfire resources, scientists with the Rocky Mountain Research Station and its partners have drawn on years of science/management collaboration to compile an online resource called the After Fire Toolkit and Information site. The After Fire Toolkit, which can be found at www.fs.usda.gov/rmrs/ tools/after-fire-toolkit-southwest, came about following a 2014 science and land management workshop to identify and prioritize land managers’ research needs for enhancing longterm resilience of ecological systems to wildfire. The Toolkit includes technical...

Reliable predictions of emissions from wildland fires are a key element of smoke management programs. Emission factors (the amount of pollutants produced per amount of fuel consumed) are used in models to estimate the composition of smoke. Over the past two decades, laboratory and field studies have made great progress in characterizing the chemical composition of smoke and quantifying emission factors. However, until recently, the widely used First Order Fire Effects Model (FOFEM) did not incorporate these advances in smoke science. A recent Rocky Mountain Research Station project...

Mastication reduces forest vegetation into small chunks by grinding, shredding, or chopping material with specialized equipment. The type of equipment varies from using a front-end to a boom-mounted rotary blade to a drum-type head. Forest managers use mastication to remove competition, prepare a site for regeneration, release sapling-sized trees, and convert ladder fuels to surface fuels. This Science You Can Use article describes the potential benefits of mastication as a forest management tool, presented in the form of a set of decision trees that can guide land managers in choosing the...

Wildfires in the western United States are expected to increase both in size and severity in coming decades. These trends are likely to accelerate large-scale habitat loss and fragmentation for the spotted owl in the Pacific Northwest, California, and the Southwest. All three subspecies that occupy these regions have declined over the last century, and the Mexican and northern subspecies are listed as threatened under the Endangered Species Act in the United States. Predicted changes in the extent and severity of wildfire are driven by a combination of climate change and cumulative effects...