Time-since-death and its effect on wood from beetle-killed Engelmann spruce in southwest Colorado

2016 Fall.Includes bibliographical references.Spruce beetles (Dendroctonus rufipennis) have caused extensive mortality on 1.5 million acres in Colorado during the current epidemic. There is considerable interest in harvesting treatments aimed at removing dead trees for reasons of fire risk, watershed health, and human dimensions. The byproducts from these treatments can either be viewed as a difficult and costly disposal problem or an opportunity for the recovery of forest products. However, a major barrier to the latter option is the lack of knowledge about how the material changes with time standing dead. Ten plots were selected on the Rio Grande National Forest (RGNF), from which 86 Engelmann spruce (Picea engelmannii) trees were felled and sampled. Tree rings were analyzed to determine Time-Since-Death (TSD) on all study trees. TSD and other variables such as diameter, elevation, and bark retention were used to develop models predicting the deterioration rate from beetle mortality (seasoning check, heart rot, and sap rot). In a separate mill study, eleven trees from the RGNF were milled to dimensional lumber to determine the lumber tally, prevalence of blue stain, and lumber grade breakdown. Checking was found to be most strongly correlated with tree diameter, and the effect of TSD was most pronounced at larger diameters. Higher elevations and increased bark retention served to reduce or slow checking. Sap rot was found to increase with TSD, but heart rot was not. Many study trees had moisture contents suitable for the development of rot. In the mill study, older dead trees produced a lower percentage of select structural lumber than control trees. Net Scribner was a poor predictor of lumber tally; gross Scribner and product potential cubic were more accurate. Results from this study may help land managers maximize sawtimber recovery by prioritizing treatment areas. Information such as tree diameter, TSD, and elevation will allow foresters to better differentiate stands that have already been subject to severe deterioration from those that will in short order

High-resolution sub-ice-shelf seafloor records of 20th-century ungrounding and retreat of Pine Island Glacier, West Antarctica.

Pine Island Glacier Ice Shelf (PIGIS) has been thinning rapidly over recent decades, resulting in a progressive drawdown of the inland ice and an upstream migration of the grounding line. The resultant ice loss from Pine Island Glacier (PIG) and its neighboring ice streams presently contributes an estimated ∼10% to global sea level rise, motivating efforts to constrain better the rate of future ice retreat. One route toward gaining a better understanding of the processes required to underpin physically based projections is provided by examining assemblages of landforms and sediment exposed over recent decades by the ongoing ungrounding of PIG. Here we present high-resolution bathymetry and sub-bottom-profiler data acquired by autonomous underwater vehicle (AUV) surveys beneath PIGIS in 2009 and 2014, respectively. We identify landforms and sediments associated with grounded ice flow, proglacial and subglacial sediment transport, overprinting of lightly grounded ice-shelf keels, and stepwise grounding line retreat. The location of a submarine ridge (Jenkins Ridge) coincides with a transition from exposed crystalline bedrock to abundant sediment cover potentially linked to a thick sedimentary basin extending upstream of the modern grounding line. The capability of acquiring high-resolution data from AUV platforms enables observations of landforms and understanding of processes on a scale that is not possible in standard offshore geophysical surveys

The Gift:Transforming Lives through Organ Donation

It is my great pleasure to introduce this comic. Our project originated from an honest conversation with my friend and colleague Prof Chris Murray: how to communicate complex issues surrounding the issue of organ donation? Over the last seven years I have had the honour of being an ambassador for the Organ Donation campaign by telling my son, Andrew’s, story.Through my role as an Organ Donation ambassador I meet courageous and selfless people. Some are in desperate need of hope, some are in the position to provide hope, and those who, through their professionalism and dedication, transform lives.Our sincere thanks for the support of the following organisations: University of Dundee; the NHS Blood and Transplant Specialist Nurses in Organ Donation; Dundee Comics Creative Space; Good Life, Good Death, Good Grief, and the Organ Donation Comics team. it is only through their support that this projectcame to fruition.In the following pages we share heartfelt stories and life experiences related to organ donation. By doing so we hope to bring awareness to a wider audience and prompt honest conversations about organ donation.Finally, I would like thank my sons Andrew and Stuart for warming my heart. Through tears and laughter we present to you… The Gift

Maria Cosway’s Hours: Cosmopolitan and Classical Visual Culture in Thomas Macklin’s Poets Gallery

Thomas Macklin’s Gallery of Poets opened at the Mitre Tavern in Fleet Street in 1788 with the aim to ‘display British Genius’ through ‘Prints Illustrative of the Most Celebrated British Poets’. Early newspaper coverage promised ‘a monument of the powers of the pencil in England, as the Vatican is at Rome’. The incongruous juxtaposition between Fleet Street and the Vatican spells out the cosmopolitan ambition of the literary gallery phenomenon through its real and imagined geographies of display. Through the format of the paper gallery of prints, Macklin’s Poets offered the inventions of British Poets as a repository of painting. This chapter examines how the cosmopolitan idiom of the paper gallery is negotiated in the first number of Macklin’s Poets. This essay examines the extent to which this ambition was achieved in the first Number of Macklin’s Poets which carried an engraving of Maria Cosway’s The Hours, originally a painting with an impressively European iconographic heritage. The painting was first exhibited at the Royal Academy in 1783, and was retroactively associated by Macklin with Thomas Gray’s ‘Ode on the Spring’. The trope of the Hours brought with it a weighty provenance derived from classical marble bas-relief, through the antiquarian pages of Pietro Santi Bartoli and Bernard de Montfaucon to Flaxman’s designs for Wedgwood plaques and vases. Cosway’s name also imported into Gray’s poem her reputation as a cosmopolitan, cultured woman who had completed the Grand Tour and who moved in elite circles including those of the Prince of Wales in London and the Duke of Orleans, Pierre d’Hancarville and Thomas Jefferson in Paris. The iconographies of the painting, the print, and the poem articulate a European cosmopolitan tradition for British Art

Modelling variation in wood stiffness of Pinus ponderosa using static bending and acoustic measurements [data file]

Wood removed in Southwestern US forest restoration treatments currently has limited markets and thus low value. One important property of wood in structural products is its stiffness (measured as modulus of elasticity), which is known to vary systematically within trees. Directly measuring wood stiffness is expensive, time consuming and destructive. Therefore, we tested samples of ponderosa pine (Pinus ponderosa var. scopulorum Engelm.) from northern Arizona destructively in bending and also non-destructively using acoustic velocity (AV) methods. In total, we tested multiple pith-to-bark small clear (2.54 × 2.54 × 40.64 cm) samples from up to four heights in 103 trees. We first measured the standing-tree AV of sample trees, then the AV of small clear samples, and finally measured wood stiffness using three point static bending tests. We found that a Michaelis–Menten curve was a good fit to the radial profile of wood stiffness, with a steep increase outward from the pith that approached an asymptote. The AV of small clear samples, coupled with measured volumetric density values, approximated the static modulus of elasticity values with high accuracy (r2 =0.86). At the stand level, a model predicting standing tree AV from tree morphology fit the data well (r2 =0.77). Results indicate that southwestern ponderosa pine contains outerwood with relatively high stiffness that could be suitable for structural products. However, when assessed using wood stiffness, the trees take a long time to reach maturity (∼50 years) and thus the corewood proportion is large. AV measurements are a good way to assess variability within and among stands and thus could be employed to segregate the resource by expected stiffness values. Segregation could help identify stands not suitable for structural uses and direct them toward more appropriate products

Associations between Australian students’ literacy achievement in early secondary school and senior secondary participation in science: accessing cultural and science capital

ABSTRACT Introduction Factors affecting student pathways in senior secondary science The literacy factor in learning science Aim and research questions Method A Bourdieusian framing of capital and forms of science capital Results and discussion Conclusion Disclosure statement References Full Article Figures & data References Citations Metrics Reprints & Permissions PDF EPUB ABSTRACT Many factors are claimed to explain Australian students’ declining participation rates in senior secondary science subjects. These include, for instance, the influences of SES, indigeneity, and gender. While acknowledging the compelling case for these factors affecting student pathways, in this study we explore associations between students’ literacy achievement test scores in early secondary school and their senior secondary participation in science. Our analyses of Australian national literacy testing data indicated that students who subsequently studied physics, chemistry, and biology showed stronger foundational literacy competence than students not studying these subjects. Drawing on a Bourdieusian perspective, this research explores the conversion of cultural capital, in the form of language literacy achievement, into science capital. We consider that these findings (a) reconfirm the foundational role of literacy in all science learning, and (b) support a growing research agenda that focuses on how students can learn the particular literacies of science before senior secondary study. Our findings also have broader implications for policy and practices that support school student participation in science study

Forest Bio-Hubs to Enhance Forest Health While Supporting the Emerging Bioeconomy—A Comparison between Three U.S. Regions

The emerging bioeconomy requires new supply chain paradigms for biomass materials to reach processing centers. Forest bio-hubs can be thought of as networks of collection points to facilitate biomass supply chains that feed from forest to central processing facilities. The design and functionality of forest bio-hubs depends on the form (e.g., vertically and horizontally integrated), and the quality and volume of feedstocks. In this paper we conceptually develop the potential role of forest bio-hubs. We then compare current bio-hub development in three U.S. regions—the Pacific Northwest, the southwest region, and the southeastern U.S. We use a “SWOT” framework to compare strengths, weaknesses, opportunities, and threats for each region. We consider transportation distances, topography, proximity to markets, harvesting methods, and wood products development. Innovation and adaptability would play key roles in forest bio-hub development, especially with dynamic conditions related to markets, wildfire risks, biomass utilization policy, and community socioeconomic factors