Effect of gap harvesting on epiphytes and bark-dwelling arthropods in the Acadian forest of central Maine

2007 ◽  
Vol 37 (11) ◽  
pp. 2175-2187 ◽  
Author(s):  
Kathryn M. Miller ◽  
Robert G. Wagner ◽  
Stephen A. Woods
Keyword(s):  
Canonical Correlation ◽  
Acer Rubrum ◽  
Positive Association ◽  
Stem Bark ◽  
Red Maple ◽  
Arthropod Communities ◽  
Undisturbed Forest ◽  
Bark Texture ◽  
The Relationship

Using a long-term silvicultural experiment, we (i) investigated how epiphyte and arthropod communities were affected by height on the stem, bark texture, and stem diameter of red maple ( Acer rubrum L.) trees, (ii) examined how harvest gaps influenced epiphyte and arthropod communities on red maple boles, and (iii) explored whether these effects influenced the relationship between the epiphyte and arthropod communities. Arthropod and epiphyte assemblages dwelling on the bark of red maple trees located in undisturbed forest and harvest gaps varied with height. Bryophytes, Cladonia spp., and cyanolichens were most abundant near the base of the tree, while noncyano, foliose lichens and fruticose lichens were most abundant 4–6 m above the ground. Acari, Araneae, and Collembola were most abundant near the base of the tree, while Diptera were most abundant above 2 m. A previously undocumented assemblage of dipterans (flies), primarily in the suborder Nematocera, was found. Gap harvesting reduced the abundance of bryophytes, Collembola (springtails), Araneae (spiders), and total arthropods on the bark of red maple. Canonical correlation analysis revealed a positive association between bryophytes, Collembola, and Araneae. A strong correlation between Collembola and Araneae suggested a possible trophic interaction that may be affected by gap harvesting through a reduction in bryophyte abundance.

scholarly journals Statistical Analysis of Causality between Capital Structure and Firm Profitability: Evidence from Bosnia and Herzegovina

2015 ◽  
Vol 1 (1-2) ◽  
pp. 1-11
Author(s):  
Emina Resić ◽  
Jasmina Mangafić ◽  
Tunjo Perić
Keyword(s):  
Capital Structure ◽  
Bosnia And Herzegovina ◽  
Canonical Correlation ◽  
Debt Structure ◽  
Short Term ◽  
The Relationship ◽  
Structure Choice ◽  
Capital Structure Choice ◽  
The Capital Structure

Abstract This research is designed to examine the relationship between the capital structure and profitability of non-financial firms in Bosnia and Herzegovina during the ten years period, from 2003-2012. The goal is to prove the existence of the relationship between the firm’s capital structure choice and its profitability. The analysis is extended by including the debt structure and differentiating between the types of debt such as the long-term and the short-term ones. Canonical correlation and multiple regression analysis are used. The results of the multivariate canonical correlation analysis provide support to a hypothesis that the capital structure and profitability have statistically significant relationships. Furthermore, the findings provide support that firms develop different patterns of profitability depending on the capital structure choice. We found that an increasing proportion of short-term debt and long-term debt in the overall liability of the firm reduces its profitability.

Relationships Among Potassium, Calcium and Trace Elements in Tree Leaves and Associated Canopy Arthropods

1990 ◽  
Vol 25 (3) ◽  
pp. 439-449 ◽  
Author(s):  
Lance S. Risley
Keyword(s):  
Tree Species ◽  
Acer Rubrum ◽  
Nutritional Ecology ◽  
Nutrient Cycles ◽  
Red Maple ◽  
Yellow Poplar ◽  
Flowering Dogwood ◽  
Quercus Prinus ◽  
The Relationship

There is a paucity of information that describes the relationship between the suite of nutrient elements in tree foliage and associated arthropod assemblages. Foliage from chestnut oak (Quercus prinus), hickories (Carya spp.), yellow poplar (Liriodendron tulipifera), red maple (Acer rubrum), and flowering dogwood (Cornus florida) and associated canopy arthropods were collected in an undisturbed and a 15 yr-old successional forested watershed and analyzed for K, Ca, Mn, Fe, Cu, Zn, Rb, and Sr. Foliar Mn and Sr were found in higher concentrations in the undisturbed watershed. Foliage from hickories was generally higher in concentrations of metals (Mn, Fe, Cu, Zn) compared with other tree species. Dogwood foliage had significantly higher concentrations of Ca and significantly lower concentrations of Mn than other tree species (P < 0.05). Concentrations of foliar elements in herbivore-damaged and undamaged leaves did not differ significantly (P > 0.05). Concentrations of elements in and among arthropod feeding categories varied substantially such that no trends were apparent among tree species and between watersheds. The most apparent trend among arthropod feeding categories was the relatively large accumulation of K in chewing herbivores (primarily caterpillars). In general, there appeared to be increases in K, Fe, Cu, and Zn concentrations from primary producers to consumers. This study contributes to arthropod nutritional ecology and to defining the role of canopy arthropods in forest ecosystem nutrient cycles.

scholarly journals Osteoarthritis and the Mediterranean Diet: A Systematic Review

Nutrients ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 1030 ◽  
Author(s):  
Isabel Morales-Ivorra ◽  
Montserrat Romera-Baures ◽  
Blanca Roman-Viñas ◽  
Lluis Serra-Majem
Keyword(s):  
Systematic Review ◽  
Mediterranean Diet ◽  
Positive Association ◽  
Cartilage Degradation ◽  
Epidemiological Evidence ◽  
Cross Sectional ◽  
The Mediterranean ◽  
The Relationship

Osteoarthritis (OA) affects 240 million people globally. Few studies have examined the links between osteoarthritis and the Mediterranean diet (MD). The aim of this paper was to systematically review and analyze the epidemiological evidence in humans on the MD and its association with OA. A systematic search of EMBASE identified three studies that explored the association between MD and OA. Two of them were cross-sectional and the third one was a 16-week randomized clinical trial. Prisma declaration was followed to carry out this review. These studies described a positive association between a higher adherence to a MD and the quality of life of participants suffering OA. The prevalence of OA was lower in participants with a higher adherence to a Mediterranean diet. Biomarkers of inflammation and cartilage degradation related to OA were also analyzed and significant differences were detected only for IL1-α, which decreased in the MD group. Exploring the relationship between MD and OA is complex, moreover, the limited evidence and methodological differences in such studies makes it difficult to compare results. In conclusion, the three studies included in this systematic review demonstrated some relation between osteoarthritis and a Mediterranean diet. However, prospective and longer interventions are required to evaluate the long-term efficacy of the Mediterranean diet to improve symptomatology and preventing osteoarthritis.

Pin cherry effects on Allegheny hardwood stand development

1999 ◽  
Vol 29 (1) ◽  
pp. 73-84 ◽  
Author(s):  
Todd E Ristau ◽  
Stephen B Horsley
Keyword(s):  
Sugar Maple ◽  
Volume Growth ◽  
Acer Rubrum ◽  
Basal Area ◽  
High Density ◽  
Stand Development ◽  
Black Cherry ◽  
Red Maple ◽  
White Ash

Pin cherry (Prunus pensylvanica L.) develops an early height advantage over associated species. Data from three long-term studies, extending up to 70 years after complete overstory removal, were used to evaluate the effects of pin cherry density on associates. Survival of seedling-origin stems of black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), and sugar maple (Acer saccharum Marsh.) at age 15 decreased as the density of pin cherry >1.5 m tall at age 3 increased. The regression of pin cherry with black cherry was particularly strong (R2 = 0.632). Height of the tallest black cherry and white ash (Fraxinus americana L.) at age 15 also decreased. If the density of pin cherry at age 3 was > 1 stem > 1.5 m tall per 0.0004 ha (high density), the number of black cherry fell below full stocking at age 15. When pin cherry occurred in high density, it lived longer than when it occurred at low density (< 1 stem > 1.5 m tall per 0.0004 ha). High pin cherry density early in stand development delayed the time when shade-intolerant and shade-intermediate species reached a stable proportion of the total basal area. In the long term, pin cherry reduced stand diameter and volume growth, particularly of black cherry.

scholarly journals Modeling the impacts of hemlock woolly adelgid infestation and presalvage harvesting on carbon stocks in northern hemlock forests

2017 ◽  
Vol 47 (6) ◽  
pp. 727-734 ◽  
Author(s):  
Jeffrey Krebs ◽  
Jennifer Pontius ◽  
Paul G. Schaberg
Keyword(s):  
Acer Rubrum ◽  
Analysis Data ◽  
C Sequestration ◽  
Hemlock Woolly Adelgid ◽  
Adelges Tsugae ◽  
Red Maple ◽  
C Storage ◽  
Model C ◽  
Successional Pathways

To better understand the potential impact of the invasive hemlock woolly adelgid (HWA, Adelges tsugae Annand) and presalvage activities on carbon (C) dynamics in northern stands of eastern hemlock (Tsuga canadensis (L.) Carr.), we used the Forest Vegetation Simulator and Forest Inventory and Analysis data to model C storage and successional pathways under four scenarios: presalvage harvesting; HWA-induced mortality; presalvage harvesting plus HWA-induced mortality; and no disturbance (control). Our simulation showed that all treatments differed in total C storage in the short term, with HWA-induced mortality providing the highest total C storage due to regeneration and ingrowth of replacement species combined with retention of standing and downed deadwood. At the end of the 150-year simulation, all disturbance scenarios had significantly lower total C than the control. The cumulative net C gain was lower for the two presalvage scenarios than for the HWA scenario, indicating that allowing HWA to progress naturally through a stand may result in the least impact to long-term C sequestration and net C storage. While differences were not significant on low hemlock density stands, impacts to the estimated 267 000 ha of northeastern forests where hemlock is dominant could result in conversion to red maple (Acer rubrum L.) and a net loss of over 4 million metric tons of potentially sequestered C over the next 150 years.

The impact of gelotophobia, gelotophilia and katagelasticism on creativity

2013 ◽  
Vol 26 (4) ◽  
Author(s):  
Yu-Chen Chan ◽  
Hsueh-Chih Chen ◽  
Joseph Lavallee
Keyword(s):  
Positive Association ◽  
Negative Influence ◽  
Creative Performance ◽  
Long Term Effects ◽  
Short Term ◽  
Creative Behavior ◽  
Broaden And Build Theory ◽  
The Impact ◽  
The Relationship

AbstractA number of studies have found that humor has a positive short-term effect in terms of enhancing creativity, but few have examined its long-term effects, and few have considered different personality traits when exploring this connection. The present study seeks to address this gap by examining the relationship between creativity and dispositions towards ridicule and being laughed at. We conceptualized humor-induced mirth as a positive emotion within the framework of broaden-and-build theory (Fredrickson 1998), with the potential to foster an individual's disposition towards creative behavior. We hypothesized that this potential would depend on different dispositions towards ridicule and being laughed at. Path analysis was then used to explore the impact of gelotophobia, gelotophilia and katagelasticism on creative performance, with creative disposition as a mediating variable. Gelotophobia, the fear of being laughed at, was found to correlate negatively with creative disposition, and may also exert an indirect negative influence on creative performance through its association with creative disposition. Gelotophilia, the joy of being laughed at, on the other hand, appears to have a partially mediated influence on creativity, exhibiting both a direct and an indirect positive relation through its positive association with creative disposition. No significant relation was observed between katagelasticism (the joy of laughing at others) and creativity.

ESTIMATING EPIDEMIC POPULATIONS OF THE LESSER MAPLE SPANWORM (LEPIDOPTERA: GEOMETRIDAE)

1979 ◽  
Vol 111 (2) ◽  
pp. 189-200
Author(s):  
W. J. A. Volney
Keyword(s):  
Unit Area ◽  
Larval Density ◽  
Acer Rubrum ◽  
Strong Relationship ◽  
Stem Diameter ◽  
Sampling Techniques ◽  
Red Maple ◽  
The Mean ◽  
The Relationship ◽  
Number Of Shoots

AbstractThe distribution of lesser maple spanworm, Itame pustularia (Gn.) (Lepidoptera: Geometridae) larvae in red maple, Acer rubrum L., crowns and of pupae under these trees, and the relationship between the number of shoots on these trees and several easily-measured tree dimensions are used to design sampling techniques for estimating the mean number of larvae per shoot and the mean number of pupae per unit area in epidemic populations. An estimate of the total number of larvae per unit area is obtained from the product of larval density and the number of shoots per unit area. Some indication of how this latter estimate might be obtained is discussed. Because of the strong relationship between stem diameter and the number of shoots on a tree, a double sample procedure can be designed based on shoot counts from a relatively small number of trees. Auxiliary measurements on a large number of trees can improve the precision of the estimate.

scholarly journals Evaluation of Systemic Insecticides for Potato Leafhopper Control in Field-Grown Red Maple

2009 ◽  
Vol 27 (1) ◽  
pp. 17-23
Author(s):  
J.B. Oliver ◽  
D.C. Fare ◽  
N. Youssef ◽  
M.A. Halcomb ◽  
M.E. Reding ◽  
...  
Keyword(s):  
Plant Root ◽  
Acer Rubrum ◽  
Potato Leafhopper ◽  
Empoasca Fabae ◽  
Red Maple ◽  
Trunk Diameter ◽  
Systemic Insecticides ◽  
Gel Treatment ◽  
Application Methods

Abstract Systemic insecticides and application methods were evaluated in two trials that began in 2005 and 2006 for control of potato leafhopper (Empoasca fabae [Harris]) on four red maple (Acer rubrum L.) cultivars and rated annually through 2007. Treatments evaluated in this study included surface drenches of imidacloprid plus cyfluthrin (Discus) or imidacloprid plus bifenthrin (Allectus SC), clothianidin (Arena 50WDG), dinotefuran (Safari 20SG), or thiamethoxam (Flagship 25WG); soil inserted treatments of imidacloprid formulated as an experimental tablet or as an experimental gel; or a plant root dip of Discus + Terra-Sorb hydrogel. In the 2005 trial, a one-time drench of Discus or two imidacloprid tablets significantly reduced leafhopper damage to red maple for a 3-year period. In the 2006 trial, a one-time drench of Allectus, Discus, Arena, Flagship, and Safari significantly reduced leafhopper damage for 2 years. In most cases, the Discus drench and root dip treatments were initially more effective than the imidacloprid tablets or the gel treatment. However, in general, the efficacy of imidacloprid tablet or gel treatments increased in subsequent years. Two imidacloprid tablets were more effective than one. Likewise, higher imidacloprid drench rates were more effective than lower rates. Most insecticide treatments significantly increased red maple trunk diameter, although this effect varied with cultivar and time. Allectus and Discus drench treatments significantly increased the branch and internode length of ‘Franksred’ maple in the 2005 trial. Results of this study indicate long-term potato leafhopper control with systemic insecticides and enhanced growth in red maple.

scholarly journals Long-term fire history of maple (Acer) forest sites in the central St. Lawrence Lowland, Quebec

2016 ◽  
Vol 46 (6) ◽  
pp. 822-831 ◽  
Author(s):  
Serge Payette ◽  
Vanessa Pilon ◽  
Pierre-Luc Couillard ◽  
Mathieu Frégeau
Keyword(s):  
Sugar Maple ◽  
Fire History ◽  
Mixed Forest ◽  
Acer Rubrum ◽  
Quebec City ◽  
Red Maple ◽  
Conifer Forest ◽  
Disturbance Factor ◽  
History Of

In the St-Lawrence lowlands, sugar maple (Acer saccharum Marsh.) is considered the dominant species of old-growth deciduous forests, whereas red maple (Acer rubrum L.) tends to dominate sites recently disturbed by logging and agricultural practices. Considering that the long-term influence of fire is not documented for such stands, we reconstructed the postglacial tree composition (as deduced from charcoal species) and fire history of a sugar maple stand (Ste-Françoise area) and a red maple stand (Villeroy area) located southwest of Québec City, Canada. The sites are 10 km apart and show contrasting soil and landform features. Using botanical identification and 14C dating of soil macrocharcoal, we found that fire struck both maple stands 14–20 times since deglaciation. Most fires occurred in the early Holocene and during the last 2000 years, with the mid Holocene being a period with low fire frequency or no fires. During the last 1600 years, the Villeroy stand shifted from a Tsuga canadensis (L.) Carrière – conifer forest to a mixed forest and, most recently, to a red maple stand as fire became more frequent, possibly due to human activities of the last 400 years. This study confirms the influence of fire on the development of maple forests. Fire should be considered as an important disturbance factor in the dynamics of temperate deciduous and mixed forests.

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