Winter injury to subalpine red spruce: influence of prior vigor and effects on subsequent growth

1992 ◽  
Vol 22 (6) ◽  
pp. 888-892 ◽  
Author(s):  
David R. Peart ◽  
Nathan J. Poage ◽  
Matthew B. Jones

We assessed the relationship between prior vigor and severity of winter injury to trees and saplings of red spruce (Picearubens Sarg.) at Mount Moosilauke, New Hampshire. Severity of injury was quantified as percent foliar damage on current-year needles after severe injury in the winter of 1988–1989. There was no relationship between severity of injury and prior crown condition. There was only a weak tendency for trees with high live crown ratios to be less damaged than trees with proportionally smaller crowns. Severity of winter injury was not correlated with prior growth rates in the 1-, 2-, or 5-year periods preceding injury, for either trees (radial growth) or saplings (extension growth). However, crown condition of trees and saplings deteriorated significantly following injury. For both trees and saplings, prior growth and subsequent growth were positively correlated for the 1- and 2-year periods before and after the winter injury event. Effects of winter injury on growth in 1989 and 1990 were analyzed using growth ratios (subsequent growth relative to prior growth) to avoid ambiguity resulting from individual differences in growth rates. Severity of winter injury had no effect on growth ratios in the 1- or 2-year periods following winter injury. Although no effects on growth were detected following a single winter injury event, it remains plausible that successive, severe episodes of winter injury could reduce growth and increase mortality risk in red spruce.

1990 ◽  
Vol 20 (8) ◽  
pp. 1219-1227 ◽  
Author(s):  
Thomas G. Huntington ◽  
David R. Peart ◽  
James Hornig ◽  
Douglas F. Ryan ◽  
Stuart Russo-Savage

We measured soil chemical properties and red spruce (Picearubens Sarg.) foliar chemistry and crown condition in the spruce-fir vegetation zone at Mount Moosilauke, New Hampshire. Our measurements were made in or adjacent to permanent plots stratified by elevation, aspect, and soil type. Soils were analyzed for exchangeable Ca, Mg, K, and Al and extractable P and Mn. Foliage was analyzed for Ca, Mg, K, Al, P, and Mn. Based upon the best available provisional standards for red spruce foliar element sufficiency, 1-year-old needles showed a moderate P deficiency (1000–1400 mg•kg−1), Mg levels in a transitional zone from deficiency to sufficiency (600–720 mg•kg−1), and Ca and K levels in a range sufficient for good growth. Foliar element concentrations were not correlated with crown condition. Extractable soil P (kg•ha−1 and cmol ion charge•kg−1) was positively correlated with crown condition. The only significant relationships found between soil exchangeable base cations and crown condition were positive correlations for Ca and Mg (kg•ha−1) in the Oi + Oe horizon. Several factors suggest that red spruce at high elevations at Mount Moosilauke was not stressed from base cation limitations: (i) foliar element concentrations were generally in sufficient ranges, (ii) crown condition was not related to foliar element concentration, (iii) relationships between exchangeable soil cations and foliar concentration or crown condition were generally not significant or were inconsistent between soil horizons.


1991 ◽  
Vol 21 (9) ◽  
pp. 1380-1389 ◽  
Author(s):  
David R. Peart ◽  
Matthew B. Jones ◽  
Peter A. Palmiotto

We report the severity and detailed spatial patterns of winter injury to red spruce (Picearubens Sarg.) in the winter of 1988–1989 and assess support for the desiccation and freezing hypotheses. Foliar injury was quantified at three elevations (840, 990, and 1140 m) and on east- and west-facing slopes in the spruce-fir zone at Mount Moosilauke, New Hampshire. Overall, 29% of current-year foliage on red spruce trees was killed by winter injury. Injury increased with elevation. There was a weak tendency for winter injury to be higher on the sun-exposed south sides of crowns, but substantial injury also occurred on shaded foliage. Injury increased markedly with height in crown at high elevation, but decreased with height at low elevation. The results appear inconsistent with desiccation as the main cause of winter injury. Elevational trends in foliar injury are consistent with the freezing hypothesis, but the strong trends in foliar injury by height within trees cannot be fully explained without further data on spatial variation in microclimate and freezing tolerance. Failure to break bud was assessed on the same spatial scales as foliar injury. Bud break was least in trees and crown sections with severe foliar injury. No evidence for winter injury was found on balsam fir (Abiesbalsamea (L.) Mill.). The results support the hypothesis that winter injury may contribute to the current decline of red spruce in the northern Appalachians.


2004 ◽  
Vol 34 (8) ◽  
pp. 1784-1788 ◽  
Author(s):  
Brynne E Lazarus ◽  
Paul G Schaberg ◽  
Donald H DeHayes ◽  
Gary J Hawley

Abundant winter injury to the current-year (2002) foliage of red spruce (Picea rubens Sarg.) became apparent in the northeastern United States in late winter of 2003. To assess the severity and extent of this damage, we measured foliar winter injury at 28 locations in Vermont and surrounding states and bud mortality at a subset of these sites. Ninety percent of all trees assessed showed some winter injury, and trees lost an average of 46% of all current-year foliage. An average of 32% of buds formed in 2002 were killed in association with winter injury. Both foliar and bud mortality increased with elevation and with crown dominance, and bud mortality increased with greater foliar injury. Foliar injury in 2003 at a plantation near Colebrook, New Hampshire, was more than five times the typical levels for 9 previous years of measurement and more than twice that measured for another high-injury year. Plantation data also indicated that bud mortality in 2003 was greater than previously documented and that persistent winter injury was associated with increased tree mortality. Comparisons of our data with past studies for two sites with native red spruce also indicated that damage in 2003 was greater than other recently reported, high-injury years. Because heavy foliar and bud losses can severely disrupt the carbon economies of trees, the 2003 winter injury event could lead to further spruce decline and mortality, particularly among dominant trees at higher elevations.


2012 ◽  
Vol 33 (2) ◽  
pp. 83-88 ◽  
Author(s):  
David Moreau ◽  
Jérome Clerc ◽  
Annie Mansy-Dannay ◽  
Alain Guerrien

This experiment investigated the relationship between mental rotation and sport training. Undergraduate university students (n = 62) completed the Mental Rotation Test ( Vandenberg & Kuse, 1978 ), before and after a 10-month training in two different sports, which either involved extensive mental rotation ability (wrestling group) or did not (running group). Both groups showed comparable results in the pretest, but the wrestling group outperformed the running group in the posttest. As expected from previous studies, males outperformed women in the pretest and the posttest. Besides, self-reported data gathered after both sessions indicated an increase in adaptive strategies following training in wrestling, but not subsequent to training in running. These findings demonstrate the significant effect of training in particular sports on mental rotation performance, thus showing consistency with the notion of cognitive plasticity induced from motor training involving manipulation of spatial representations. They are discussed within an embodied cognition framework.


2020 ◽  
Vol 22 (3) ◽  
pp. 341-361
Author(s):  
Gonzalo Grau-Pérez ◽  
J. Guillermo Milán

In Uruguay, Lacanian ideas arrived in the 1960s, into a context of Kleinian hegemony. Adopting a discursive approach, this study researched the initial reception of these ideas and its effects on clinical practices. We gathered a corpus of discursive data from clinical cases and theoretical-doctrinal articles (from the 1960s, 1970s and 1980s). In order to examine the effects of Lacanian ideas, we analysed the difference in the way of interpreting the clinical material before and after Lacan's reception. The results of this research illuminate some epistemological problems of psychoanalysis, especially the relationship between theory and clinical practice.


2017 ◽  
pp. 119-124
Author(s):  

Introduction: Intestinal parasite infections werecommonintropical country such as Vietnam. Having good knowledge of parasitic infectious prevention and changing risk behaviors can decrease the infection rate. Objective: To evaluate the parasitic infectious rate in Vinh Thai community before and after being health education and the changing of knowledge of parasitic infectious prevention and risk behaviors. Materials and methods: 60 households in Vinh Thai commune were interviewed their knowledge of parasitic infectious prevention and examined intestinal parasite infection by Kato technique and then trained the knowledge of parasitic infectious prevention. The interview and examination parasite infectiousrate were carried out after 6 months to evaluating their knowledge. Result: Before health education, the rate of intestinal parasite infection was 17.4% with the prevalence of Ascaris lumbricoides, hookworm, whipworm, pinworm, small fluke worm and co-infection with A. lumbricoides - whipworm, hookworm-whipworm were 0.1%; 8.0%; 5.8%; 0.6%; 0.3%; 1.2% and 3.0% respectively. Six months later the rate of intestinal parasite infection was decreased in 12.6% even though not statistical significantly. However, there were no case of small fluke worm and co-infection with hookworm-whipworm. Receiving health education, their knowledge of parasitic infectious prevention was higher significantly but their risk behaviors were not changed so much. Conclusion: Health education can change the rate of parasite infection with higher knowledge of parasitic infectious prevention but it was necessary continuous study to change the risk behaviors. Key words: intestinal parasite, health education


2018 ◽  
Vol 69 (05) ◽  
pp. 381-389
Author(s):  
MENGÜÇ GAMZE SÜPÜREN ◽  
TEMEL EMRAH ◽  
BOZDOĞAN FARUK

This study was designed to explore the relationship between sunlight exposure and the mechanical properties of paragliding fabrics which have different colors, densities, yarn counts, and coating materials. This study exposed 5 different colors of paragliding fabrics (red, turquoise, dark blue, orange, and white) to intense sunlight for 150 hours during the summer from 9:00 a.m. to 3:00 p.m. for 5 days a week for 5 weeks. Before and after the UV radiation aging process, the air permeability, tensile strength, tear strength, and bursting strength tests were performed. Test results were also evaluated using statistical methods. According to the results, the fading of the turquoise fabric was found to be the highest among the studied fabrics. It was determined that there is a significant decrease in the mechanical properties of the fabrics after sunlight exposure. After aging, the fabrics become considerably weaker in the case of mechanical properties due to the degradation in both the dyestuff and macromolecular structure of the fiber


Author(s):  
P.A. Popov ◽  
◽  
D.V. Gruznov ◽  
S.V. Tokarev ◽  
◽  
...  

The article presents the results of determining the relationship between the total microbial number and microbial ATP on the surface of milking equipment before and after treatment with neutral anolyte ANK-SUPER. The possibility of using the ATP-bioluminescence method to control the quality of sanitation of milking equipment on dairy farms is shown. Laboratory studies revealed a proportional relationship between the level of bacterial ATP and the number of bacteria on the surface of milking equipment before and after sanitation.


Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 4997
Author(s):  
Victor C. Le ◽  
Monica L. H. Jones ◽  
Kathleen H. Sienko

Postural sway has been demonstrated to increase following exposure to different types of motion. However, limited prior studies have investigated the relationship between exposure to normative on-road driving conditions and standing balance following the exposure. The purpose of this on-road study was to quantify the effect of vehicle motion and task performance on passengers’ post-drive standing balance performance. In this study, trunk-based kinematic data were captured while participants performed a series of balance exercises before and after an on-road driving session in real-time traffic. Postural sway for all balance exercises increased following the driving session. Performing a series of ecologically relevant visual-based tasks led to increases in most post-drive balance metrics such as sway position and velocity. However, the post-drive changes following the driving session with a task were not significantly different compared to changes observed following the driving session without a task. The post-drive standing balance performance changes observed in this study may increase vulnerable users’ risk of falling. Wearable sensors offer an opportunity to monitor postural sway following in-vehicle exposures.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Pierre Nouvellet ◽  
Sangeeta Bhatia ◽  
Anne Cori ◽  
Kylie E. C. Ainslie ◽  
Marc Baguelin ◽  
...  

AbstractIn response to the COVID-19 pandemic, countries have sought to control SARS-CoV-2 transmission by restricting population movement through social distancing interventions, thus reducing the number of contacts. Mobility data represent an important proxy measure of social distancing, and here, we characterise the relationship between transmission and mobility for 52 countries around the world. Transmission significantly decreased with the initial reduction in mobility in 73% of the countries analysed, but we found evidence of decoupling of transmission and mobility following the relaxation of strict control measures for 80% of countries. For the majority of countries, mobility explained a substantial proportion of the variation in transmissibility (median adjusted R-squared: 48%, interquartile range - IQR - across countries [27–77%]). Where a change in the relationship occurred, predictive ability decreased after the relaxation; from a median adjusted R-squared of 74% (IQR across countries [49–91%]) pre-relaxation, to a median adjusted R-squared of 30% (IQR across countries [12–48%]) post-relaxation. In countries with a clear relationship between mobility and transmission both before and after strict control measures were relaxed, mobility was associated with lower transmission rates after control measures were relaxed indicating that the beneficial effects of ongoing social distancing behaviours were substantial.


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