Responses of soil carbon, nitrogen and cations to the frequency and seasonality of prescribed burning in a Cape Cod oak-pine forest

Author Posting. © The Author(s), 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Forest Ecology and Management 250 (2007): 234-243, doi:10.1016/j.foreco.2007.05.023.Fire is an important component of the historic disturbance regime of oak and pine forests that occupy sandy soils of the coastal outwash plain of the northeastern U.S. Today prescribed fire is used for fuel reduction and for restoration and maintenance of habitat for rare plant, animal and insect species. We evaluated the effects of the frequency and seasonality of prescribed burning on the soils of a Cape Cod, Massachusetts coastal oak-pine forest. We compared soil bulk density, pH and acidity, total extractable cations and total soil C and N in unburned plots and in plots burned over a 12-year period, along a gradient of frequency (every 1-to-4 years), in either spring (March/April) or summer (July/August). Summer burning decreased soil organic horizon thickness more than spring burning, but only summer burning every 1 to 2 years reduced organic horizons compared with controls. Burning increased soil bulk density of the organic horizon only in the annual summer burns and did not affect bulk density of mineral soil. Burn frequency had no effect on pH in organic soil, but burning every year in summer increased pH of organic soil from 4.01 to 4.95 and of mineral soil from 4.20 to 4.79. Burning had no significant effect on organic or mineral soil percent C, percent N, C:N, soil exchangeable Ca2+, Mg2+, K+ or total soil C or N. Overall effects of burning on soil chemistry were minor. Our results suggest that annual summer burns may be required to reduce soil organic matter thickness to produce conditions that would regularly allow seed germination for oak and for grassland species that are conservation targets. Managers may have to look to other measures, such as combinations of fire with mechanical treatments (e.g., soil scarification) to further promote grasses and forbs in forests where establishment of these plants is a high priority.Funding was provided by the National Park Service, The Nature Conservancy via a grant from the Mellon Foundation, the Joint Fire Science Program, and a grant from the Mellon Foundation to MBL

Stand-Level Green Biomass Equations for Sawtimber-Sized Loblolly Pine in Arkansas

Loblolly pine (Pinus taeda L.) is commercially the most important timber species in southern Arkansas and the southern United States. Results of stand-level timber inventories have traditionally been reported in terms of volume, yet loblolly pine sawtimber is bought and sold based on biomass. A straight forward stand-level conversion from volume per hectare to biomass per hectare does not exist for Arkansas, thus complicating the valuation of standing loblolly pine sawtimber. Two equations were developed to predict stand-level, outside-bark, green biomass per unit area for loblolly pine stands in southern Arkansas. The merchantable sawlog equation presented herein explained approximately 95% of the variation present and had an average error of 4.2 percent when applied to validation data. The equation for total merchantable biomass explained about 99% of the variation and had an average error of 1.5 percent when applied to validation data. Use of these equations should simplify the valuation of standing timber in loblolly pine sawtimber stands in southern Arkansas

Comparison of Three Equations for Predicting Stress Wave Velocity As A Function of Grain Angle

Assessment of a nondestructive test system for detecting defects in the gluelines of edge-glued hardwood panels required development of a mathematical relationship for predicting stress wave velocity as a function of grain angle. This relationship was necessary to understand better how stress waves propagated around gaps or flaws in a glueline. In addition, the relationship was needed to assess the influence of specimen geometry upon the effectiveness of the stress wave technique.Equations were generated by a statistical regression analysis software package and compared to Hankinson's equation. Equations were based upon measured velocity of stress waves traveling at angles between 0 and 90 degrees to the grain at 15 degree intervals in birch, black cherry, red oak, yellow-poplar, and western white pine boards. Regression analyses indicated that the best correlations were found with second order hyperbolic and parabolic equations. The two equations were compared to Hankinson's equation and to each other by using Absolute Average Error (AAE) for each equation for each species and for all species combined at each of the grain angles for which data were collected. Hankinson's equation produces the least AAE of the three equations although the hyperbolic and parabolic equations must also be considered reasonable predictors of stress wave velocity at most angles to the grain

Testing Glueline Continuity in Standard-Size Hardwood Blanks by Mechanical Methods

Glueline continuity is very critical in standard-size hardwood blanks because the blanks are cut up into small furniture parts, and a small gap in the glueline of a blank may extend across the whole part—or a gap may appear as a crack in the final product. Strength is not a critical factor. The objective of this study was to determine if a gap in a glueline can be detected by mechanical means. Furniture manufacturers want to be sure that any blank that they buy will have continuous gluelines. Every blank should be nondestructively tested, and all blanks with a defective glueline should be rejected from the shipment.Black cherry, red oak, and yellow-poplar standard-size blanks 24 inches wide and 0.75 inches thick were manufactured. Some blanks were crosscut into strips two inches along the grain. The other blanks were cut 24 inches long. Foil defect strips were placed in the middle glueline of some panels to create a gap, thus achieving a range of effective gluelines of 60, 75, 90, and 100%. Static bending perpendicular to the grain, tension perpendicular to the grain, and torsion tests were developed for testing these specimens. Five parameters—modulus of rupture and modulus of elasticity in bending, tensile strength, torsional shear strength, and modulus of rigidity—were measured to determine their sensitivity for detecting defective gluelines.Based on the results of this study, tensile strength perpendicular to the grain is the most satisfactory parameter for detecting defective gluelines. Its combination of high sensitivity and low variability would result in the smallest amount of destruction of good panels, while failing a larger number of defective panels. It was found that mechanical methods are not appropriate for determining glueline continuity since none of the parameters studied is sufficiently sensitive to detect defects of 10% or less

Evidence of Fraud, Audit Risk and Audit Liability Regimes

We investigate the effectiveness of proportionate liability in reducing the probability of fraud and audit risk relative to joint and several liability in two strategic audit settings: one that provides conclusive evidence of fraud and one that provides inconclusive evidence of fraud. In both settings the auditor makes an audit effort choice, but in the second setting the auditor also evaluates the audit evidence. Our results show that when the auditor chooses only effort, a proportionate liability rule with large marginal liability relief decreases audit risk. However, when the auditor also evaluates the audit evidence this result no longer holds.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47720/1/11142_2004_Article_5114688.pd

The effects of injection of bovine vaccine into a human digit: a case report

BACKGROUND: The incidence of needlestick injuries in farmers and veterinary surgeons is significant and the consequences of such an injection can be serious. CASE PRESENTATION: We report accidental injection of bovine vaccine into the base of the little finger. This resulted in increased pressure in the flexor sheath causing signs and symptoms of ischemia. Amputation of the digit was required despite repeated surgical debridement and decompression. CONCLUSION: There have been previous reports of injection of oil-based vaccines into the human hand resulting in granulomatous inflammation or sterile abscess and causing morbidity and tissue loss. Self-injection with veterinary vaccines is an occupational hazard for farmers and veterinary surgeons. Injection of vaccine into a closed compartment such as the human finger can have serious sequelae including loss of the injected digit. These injuries are not to be underestimated. Early debridement and irrigation of the injected area with decompression is likely to give the best outcome. Frequent review is necessary after the first procedure because repeat operations may be required

Proteomic analysis of six- and twelve-month hippocampus and cerebellum in a murine Down syndrome model

This study was designed to investigate the brain proteome of the Ts65Dn mouse model of Down syndrome. We profiled the cerebellum and hippocampus proteomes of 6- and 12-month-old trisomic and disomic mice by difference gel electrophoresis. We quantified levels of 2082 protein spots and identified 272 (170 unique UniProt accessions) by mass spectrometry. Four identified proteins are encoded by genes trisomic in the Ts65Dn mouse. Three of these (CRYZL11, EZR, and SOD1) were elevated with p-value \u3c0.05, and 2 proteins encoded by disomic genes (MAPRE3 and PHB) were reduced. Intergel comparisons based on age (6 vs. 12 months) and brain region (cerebellum vs. hippocampus) revealed numerous differences. Specifically, 132 identified proteins were different between age groups, and 141 identified proteins were different between the 2 brain regions. Our results suggest that compensatory mechanisms exist, which ameliorate the effect of trisomy in the Ts65Dn mice. Differences observed during aging may play a role in the accelerated deterioration of learning and memory seen in Ts65Dn mice