2,909 research outputs found
Environmental Performance Index for the Forest
Comparative environmental performance indices for energy use, global warming potential (GWP), air, water, and solid waste emissions covering the stages of processing from the harvesting of wood and the extraction of non-renewable materials to the construction of a house using different materials are developed in other articles. Developing performance indices that compare renewable resources and their environmental impacts on the land base to the depletion of non-renewable resources is problematic. Materials that involve mining are inherently not renewable compared to forest resources, which are renewable over some rotation age of the forest. The environmental impacts on the forest are dynamic and are impacted by landscape changes with some related to the production of wood for markets. Forest ecology metrics are developed to show the impact of management alternatives based on changing stand structures. Forest diversity, measured by structure classes, is impacted by longer rotation and thinning alternatives as well as preservation and protection policies.Management alternatives can contribute to some restoration of pre-settlement conditions of forests and provides a benchmark from which to evaluate reduced stand structure diversity and loss of habitat. While a century of commercial management has reduced the diversity in the forest and in particular has increased the share of acres in both the stand initiation stage and the closed canopy or stem exclusion stage, the trend has already turned in response to demands for more forest acres under increased protection and preservation status. Increased thinning from more intensive management and policies to protect threatened species are both contributing to increased understory reinitiation and ultimately more complex old forest structures. Longer rotation management could add to this effect but at a substantial cost since the economics of long rotation management falls below acceptable levels for economic investments
Long-Term Trends of Northern Bobwhite Populations and Hunting Success on Private Shooting Plantations in Northern Florida and Southern Georgia
Nearly all broad-scale assessments (U.S. Department of the Interior, Fish and Wildlife Service [USDI-FWS], Breeding Bird Surveys, Audubon Society Christmas Bird Counts, and state game agency harvest surveys) of northern bobwhite (Colinus virginianus) population trends during the past 30 to 50 years point to widespread declines at local, regional and national scales. Long-term records of populations that do not show long-term bobwhite declines are rare. Landowners and managers in the shooting plantation country between Tallahassee, Florida and Thomasville, Georgia have been recording quail hunting and bag records for many years. Such information can provide valuable insight into the long-term trends of bobwhite populations. We therefore analyzed bag records from 5 different properties where data had been collected for periods ranging from 14 to 80+ years. Trends from these data were completely opposite from long-term trends shown from other sources such as Breeding Bird Survey and Christmas Bird Count data. These data indicate that a long-term, continuous approach to habitat management (primarily burning with prescribed fire, and frequent soil disturbance from disking) can sustain abundant bobwhite populations and high-quality shooting. These data also call into question alternative hypotheses such as invasion of the red imported fire ant and range expansion of the coyote as being responsible for the long-term bobwhite decline. Both fire ants and coyotes are common in the Thomasville-Tallahassee area, yet, abundant bobwhite populations persist, presumably as a function of high-quality habitat management
The Role of Canids in Ritual and Domestic Contexts: New Ancient DNA Insights from Complex Hunter-Gatherer Sites in Prehistoric Central California
This study explores the interrelationship between the genus Canis and hunter–gatherers through a case study of prehistoric Native Americans in the San Francisco Bay-Sacramento Delta area. A distinctive aspect of the region\u27s prehistoric record is the interment of canids, variously classified as coyotes, dogs, and wolves. Since these species are difficult to distinguish based solely on morphology, ancient DNA analysis was employed to distinguish species. The DNA study results, the first on canids from archaeological sites in California, are entirely represented by domesticated dogs (including both interments and disarticulated samples from midden deposits). These results, buttressed by stable isotope analyses, provide new insight into the complex interrelationship between humans and canids in both ritual and prosaic contexts, and reveal a more prominent role for dogs than previously envisioned
Life-Cycle Impacts of Forest Resource Activities in the Pacific Northwest and Southeast United States
A more intensive management alternative was created for each region by reallocating acres to higher management intensity classes. Harvesting activities were segmented into five stages to allow development of all inputs and outputs: (1) felling, (2) processing (bucking, limbing, cutting to length), (3) secondary transportation (skidding and yarding), (4) loading, and (5) hauling to a process point. The costs and consumption rates of energy and materials for these activities drove the log outputs, emissions, and carbon pools. Logs are allocated to wood product facilities, the primary product of the analysis, or pulp and paper mills as a co-product from the forest. Non-merchantable slash is generally left on site and is disposed of through site preparation activities. Transportation-related activities and the required diesel fuel produce by far the largest contribution to emission outputs. However, fertilizer use contributes to much of the change in emissions as acreage shifts to higher intensity management alternatives
Novel BRAF Alteration in a Sporadic Pilocytic Astrocytoma
Pilocytic astrocytoma (PA) is the most frequently encountered glial tumor (glioma or astrocytoma) in children. Recent studies have identified alterations in the BRAF serine/threonine kinase gene as the likely causative mutation in these childhood brain tumors. The majority of these genetic changes involve chromosome 7q34 tandem duplication, resulting in aberrant BRAF fusion transcripts. In this paper, we describe a novel KIAA1549:BRAF fusion transcript in a sporadic PA tumor associated with increased ERK activation and review the spectrum of BRAF genetic alterations in this common pediatric low-grade central nervous system neoplasm
Effects of Disking Versus Feed Patch Management on Northern Bobwhite Brood Habitat and Hunting Success
More than 60 years ago, Herbert Stoddard (1931:376) wrote there is little doubt that such methods [i.e., disking and harrowing] are more practical for Southeastern quail preserves than artificial plantings, which are costly on a large scale and not always effective. Incredibly, this statement, and testing it as an hypothesis, has been ignored by the bobwhite research community until the past 10 years. Therefore, we designed a pilot study to compare measures of northern bobwhite (Colinus virginianus) brood habitat (vegetation composition and arthropod biomass) and direct measures of hunting success (covey finds per half-day hunt) to test whether feed patches were really necessary for bobwhite habitat management in southern Georgia and northern Florida. We applied experimental treatments (disk only versus feed patch planting) by using shooting courses (150-250 ha each) on 2 southeastern shooting plantations during 1994, 1995 and 1996. Overall, results were equivocal between the feed patch and disking treatments; no consistent pattern or difference in brood habitat composition or hunting success was observed. One factor responsible for this pattern may be the relatively fine-grained scale (only 1-3% of the shooting courses were planted or disked) at which treatments were applied were insufficient to significantly influence bobwhite abundance. Further research using increased amounts of ground disturbance and planting (5%, 10%, 20%, etc.) will be required before the actual need for agricultural plantings can be determined in the context of their efficacy for bobwhite management. One potential result of these findings is that significant cost savings can be realized by disking rather than planting agricultural crop plants because at least 70% of the costs of planting are a function of seed, fertilizer and cultivation, whereas only about 30% are attributed to disking
Comparison of Two Methods for Quantifying Northern Bobwhite Habitat Use
Habitat use is an important ecological parameter that is used to make informed decisions about quail management and research. Statistical methods for quantifying habitat use are numerous, but few objective criteria are available to support the selection of a particular analytical approach. Therefore, we compared breeding season habitat use by radio-marked northern bobwhites (Colinus virginianus) at 2 study sites in Mississippi with 2 widely used statistical methods; Chi-square goodness-of-fit test with Bonferroni confidence intervals, and compositional analysis. These statistical methods produced similar results for both study areas; however, more detailed habitat use information was provided by compositional analysis when performed using the customary hierarchical approach. Therefore, for analysis of radio-marked quail, we recommend this method due to its effective hierarchical approach, improved statistical validity, and ability to incorporate other population parameters (e.g .. survival) into statistical models of habitat use by northern bobwhites
Effects of Seasonal Fire Applications on Northern Bobwhite Brood Habitat and Hunting Success
Since the early part of the 20th century, land managers have used prescribed fire during February and March to maintain and enhance habitat for northern bobwhites (Colinus virginianus) in southern pine forests. During the past 2 decades, some managers have started to shift their use of fire to mimic more natural lightning-season (April to August) ignitions because these fires encourage flowering of plants in intact native ground cover, and are potentially more effective at hardwood control than winter fires. Therefore, we designed a short-term pilot study to evaluate whether seasonal applications of prescribed fire had any effect on bobwhite brood habitat (as measured by vegetation composition and arthropod biomass) or bobwhite abundance (as measured by hunting success) during the subsequent fall. During the first two years of our study (1994 and 1995), results showed that arthropod biomass and bobwhite hunting success were slightly greater on the shooting course burned during lightning-season (May) than the one burned during February and March. These results indicate that applications of lightning-season fire can be used, at least on a small scale (i.e., management blocks \u3c250 ha) in southern pine forests for hardwood control, and possibly enhancement of native ground cover without short-term negative impacts on northern bobwhites
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