Relationships between root form and growth, stability, and mortality in planted versus naturally regenerated lodgepole pine in north-central British Columbia

2006 ◽  
Vol 36 (10) ◽  
pp. 2642-2653 ◽  
Author(s):  
Jeanne A Robert ◽  
B Staffan Lindgren
Keyword(s):  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Root Characteristics ◽  
Cross Sectional ◽  
Growth Stability ◽  
Risk Of Mortality ◽  
Horizontal Stability ◽  
Lower Height ◽  
Growth Differences ◽  
The Impact

The roots of container-grown and manually planted lodgepole pine, Pinus contorta Dougl. ex Loud. var. latifolia Engelm., are often deformed, potentially impacting their health relative to that of naturally regenerated trees. We evaluated 12 root characteristics to elucidate the type and severity of root deformities in planted pine aged 3–10 years, as well as to determine the impact of root form on their growth and stability. Results showed that root deformity is widespread: 95.0% of planted trees versus 50.9% of naturally regenerated trees had either moderate or severe root deformities. A logistic regression using the 12 root characteristics strongly distinguished between planted and naturally regenerated trees. Aboveground growth form was affected in that planted trees had a lower height-to-diameter ratio than naturally regenerated trees. In young planted trees with low or moderate root deformities, but not in trees with severely deformed roots (65.0% of all planted trees in our study), both height- and diameter-growth rates were higher than in naturally regenerated trees. Growth differences may be attributed to differential resource allocation resulting from translocation inhibition caused by root deformation. In spite of very different root systems, there was no difference in the horizontal stability of planted versus naturally regenerated trees. However, planted trees have a significantly lower root cross-sectional area and may therefore be at a higher risk of mortality, primarily from attack by the Warren root collar weevil, Hylobius warreni Wood.

Predicting survival of lodgepole pine stands infected with western gall rust

2006 ◽  
Vol 36 (4) ◽  
pp. 878-885 ◽  
Author(s):  
J M Wolken ◽  
P V Blenis ◽  
I Duncan
Keyword(s):  
Pinus Contorta ◽  
Management Strategy ◽  
Tree Mortality ◽  
Lodgepole Pine ◽  
Main Stem ◽  
Iteratively Reweighted Least Squares ◽  
Risk Of Mortality ◽  
Endocronartium Harknessii ◽  
Stem Gall ◽  
Pine Stands

The probability of lodgepole pine (Pinus contorta Dougl. ex Loud.) having main-stem galls caused by western gall rust, Endocronartium harknessii (J.P. Moore) Y. Hiratsuka, surviving to rotation is unknown. To evaluate survival, 400 galled trees with at least one stem gall and 400 trees without stem galls were measured in 1992 in two precommercially thinned stands approximately 20 years old. The survival of trees was assessed in 2003. Nonlinear regression using iteratively reweighted least squares was employed to estimate the survival of galled trees as a function of the proportion of the main stem encircled by galls. Galls encircling >79% and >91% of the stem in the two stands increased the risk of mortality relative to non-galled trees, with the risk increasing steeply with percent gall encirclement; smaller stem galls did not cause tree mortality. The 11-year pattern of survival of galled trees was similar for infections that occurred on the main stem and those that had reached the stem from a nearby branch infection. Based on an earlier model of gall expansion, 38%–43% of stem-galled trees would be expected to survive until age 80. Scribing of stem galls to prevent their expansion does not appear to be a feasible management strategy.

scholarly journals Biological and chemical amelioration effects on the localities degraded by bulldozer site preparation in the Ore Mts. – Czech Republic 

2012 ◽  
Vol 49 (No. 4) ◽  
pp. 141-147 ◽  
Author(s):  
V. V Podrázský ◽  
J. Remeš ◽  
I. Ulbrichová
Keyword(s):  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Mineral Soil ◽  
European Beech ◽  
Growth Potential ◽  
Adsorption Complex ◽  
White Pine ◽  
Blue Spruce ◽  
Diameter Increment ◽  
The Impact

Biological and chemical (fertilising, liming) amelioration are among the principal tools used to restore degraded sites. These techniques were also used on the Ore Mts. plateau on plots prepared by bulldozing. We evaluated the impact of these amelioration techniques by measuring tree species primary production and humus form restoration. Begun in 1983–1985, this project studied growth reaction of forest stands by measuring height and diameter increment, for the following species (blue spruce Picea pungens Engelm., European larch Larix decidua Mill., lodgepole pine Pinus contorta Dougl., Eastern white pine Pinus strobus L., alder Alnus incana Moench., European beech Fagus sylvatica L.) during the period 1994–2000. The growth potential by species decreases in the following order: larch, alder, lodgepole pine, white pine, blue spruce. Beech was almost exterminated by red deer browsing and the harsh climate; pines suffered heavily from browsing and bark stripping. Holorganic horizons were measured and basic soil chemical and mechanical characteristics were determined – pH, soil adsorption complex characteristics (using Kappen’s methodology), content of the humus and total nitrogen, exchangeable acidity and plant available macronutrients, granulometric composition of mineral soil horizons. Our results confirmed the relatively long-lasting effects of soil amendments, as well as the amelioration effects of alder, and the relatively inhibiting effects of larch and blue spruce.

A module to simulate the impact of western gall rust (Cronartium harknessii) on merchantable volume and lumber yields for lodgepole pine (Pinus contorta var. latifolia) stands in British Columbia

2019 ◽  
Vol 49 (11) ◽  
pp. 1379-1391
Author(s):  
Derek F. Sattler ◽  
James W. Goudie ◽  
Richard W. Reich
Keyword(s):  
British Columbia ◽  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Repeated Measurements ◽  
Stand Age ◽  
Individual Tree ◽  
Stem Infection ◽  
Incidence And Mortality ◽  
Tree Growth Model ◽  
The Impact

Western gall rust (Cronartium harknessii (J.P. Moore) E. Meinecke) is a pathogen that affects lodgepole pine (Pinus contorta Douglas ex Loudon var. latifolia Engelm. ex S. Watson) and has the potential to reduce lumber product yields derived from stands managed for the commercial production of timber. A dataset containing repeated measurements from 7775 trees located within the province of British Columbia, Canada, was used to develop equations that predict annual rates of stem infection, post-infection mortality, and the location of large stem galls. Results showed that annual rates of infection peaked between 3 and 5 years following stand establishment. Few new infections were predicted to occur beyond the stand age of 15 years. For an individual tree, the probability of first infection increased as its height increased relative to stand top height. The rate of mortality increased with the number of stem infections and was highest among trees infected within the first 3 years following planting. Mortality rates decreased thereafter, with many trees likely to survive to rotation. The equations predicting rust incidence and mortality were added to the Tree and Stand Simulator (TASS), an individual-tree growth model used within the province. A final equation predicting the location of large galls was added and allows TASS to account for losses due to the removal of stem defects during lumber manufacturing.

BIOLOGY AND LIFE HISTORY OF EPURAEA OBLIQUUS HATCH (COLEOPTERA: NITIDULIDAE) ON WESTERN GALL RUST

1996 ◽  
Vol 128 (2) ◽  
pp. 177-186 ◽  
Author(s):  
Cameron R. Currie ◽  
John R. Spence ◽  
W. Jan A. Volney
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Late Summer ◽  
Natural Control ◽  
Larval Instars ◽  
Endocronartium Harknessii ◽  
History Of ◽  
The Impact

AbstractThe life cycle, phenology, and abundance of Epuraea obliquus Hatch was studied near Hinton, Alberta. Most of the life cycle occurs on galls of Endocronartium harknessii (J.P. Moore) Y. Hiratsuka (western gall rust) infecting lodgepole pine (Pinus contorta Dougl. var latifolia Engelm.). Both adults and larvae feed on the spores of the fungus. Individuals of this beetle were found on most galls sampled. Adults overwinter in the soil. They emerge in the spring to seek out and colonize galls. Eggs are laid on the surface of galls, mainly under the periderm, and larvae feed on the fungus, developing through three larval instars. Larvae in the last instar drop from galls to pupate in the soil. Adults leave the soil in late summer and return to feed on inactive galls before overwintering in the soil. The phenology of E. obliquus is closely synchronized with the timing of rust sporulation and the impact of beetle feeding may be an important natural control of western gall rust.

Leaf area and tree increment dynamics of even-aged and multiaged lodgepole pine stands in Montana

1999 ◽  
Vol 29 (6) ◽  
pp. 687-695 ◽  
Author(s):  
Cassandra L Kollenberg ◽  
Kevin L O'Hara
Keyword(s):  
Leaf Area ◽  
Pinus Contorta ◽  
Stand Structure ◽  
Lodgepole Pine ◽  
Stem Volume ◽  
Age Classes ◽  
Cross Sectional ◽  
Individual Tree ◽  
Area Index ◽  
Volume Increment

Age structure and distribution of leaf area index (LAI) of even and multiaged lodgepole pine (Pinus contorta var. latifolia Engelm.) stands were examined on three study areas in western and central Montana. Projected leaf area was determined based on a relationship with sapwood cross-sectional area at breast height. Stand structure and LAI varied considerably between individual plots. LAI and stand stem volume increment were significantly higher in multiaged than even-aged stands with the exception of one study area, which had higher volume increment in even-aged stands. Older cohorts and higher canopy strata generally had greater LAI than younger cohorts and lower strata. Ratios of stem volume increment to leaf area were used to assess stand, cohort, and individual tree vigor or growing space efficiency (GSE). Even-aged stands had significantly higher GSEs in individual study areas and overall than multiaged stands. Cohort GSE generally increased with increasing age of the cohort. Stand increment was weakly associated with stand LAI. Individual tree volume increment was strongly related to projected leaf area when stands were divided by age-classes or canopy strata. These results suggest separating these stands into components, such as age classes or canopy strata, and summing predicted increment for each component may provide more accurate prediction of stand increment than using whole-stand LAI.

Multidisciplinary team decision is rare and decreasing in percutaneous vascular interventions despite positive impact on in-hospital outcomes

VASA ◽  
2019 ◽  
Vol 48 (3) ◽  
pp. 262-269 ◽  
Author(s):  
Christian-Alexander Behrendt ◽  
Tilo Kölbel ◽  
Thea Schwaneberg ◽  
Holger Diener ◽  
Ralf Hohnhold ◽  
...  
Keyword(s):  
Multidisciplinary Team ◽  
Positive Impact ◽  
Cross Sectional Study ◽  
Invasive Treatment ◽  
Cross Sectional ◽  
Hospital Outcomes ◽  
Vascular Intervention ◽  
Medical Specialties ◽  
Team Decision ◽  
The Impact

Abstract. Background: Worldwide prevalence of peripheral artery disease (PAD) is increasing and peripheral vascular intervention (PVI) has become the primary invasive treatment. There is evidence that multidisciplinary team decision-making (MTD) has an impact on in-hospital outcomes. This study aims to depict practice patterns and time changes regarding MTD of different medical specialties. Methods: This is a retrospective cross-sectional study design. 20,748 invasive, percutaneous PVI of PAD conducted in the metropolitan area of Hamburg (Germany) were consecutively collected between January 2004 and December 2014. Results: MTD prior to PVI was associated with lower odds of early unsuccessful termination of the procedures (Odds Ratio 0.662, p < 0.001). The proportion of MTD decreased over the study period (30.9 % until 2009 vs. 16.6 % from 2010, p < 0.001) while rates of critical limb-threatening ischemia (34.5 % vs. 42.1 %), patients´ age (70 vs. 72 years), PVI below-the-knee (BTK) (13.2 % vs. 22.4 %), and rates of severe TASC C/D lesions BTK (43.2 % vs. 54.2 %) increased (all p < 0.001). Utilization of MTD was different between medical specialties with lowest frequency in procedures performed by internists when compared to other medical specialties (7.1 % vs. 25.7 %, p < 0.001). Conclusions: MTD prior to PVI is associated with technical success of the procedure. Nonetheless, rates of MTD prior to PVI are decreasing during the study period. Future studies should address the impact of multidisciplinary vascular teams on long-term outcomes.

Coexistent Osteoarthritis and Parkinson’s Disease: Data from the Parkinson’s Foundation Outcomes Project

2020 ◽  
Vol 10 (4) ◽  
pp. 1601-1610
Author(s):  
Jaimie A. Roper ◽  
Abigail C. Schmitt ◽  
Hanzhi Gao ◽  
Ying He ◽  
Samuel Wu ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Study Data ◽  
Functional Mobility ◽  
Quality Improvement Initiative ◽  
Timed Up And Go ◽  
Mobility Performance ◽  
Risk Of Mortality ◽  
The Impact

Background: The impact of concurrent osteoarthritis on mobility and mortality in individuals with Parkinson’s disease is unknown. Objective: We sought to understand to what extent osteoarthritis severity influenced mobility across time and how osteoarthritis severity could affect mortality in individuals with Parkinson’s disease. Methods: In a retrospective observational longitudinal study, data from the Parkinson’s Foundation Quality Improvement Initiative was analyzed. We included 2,274 persons with Parkinson’s disease. The main outcomes were the effects of osteoarthritis severity on functional mobility and mortality. The Timed Up and Go test measured functional mobility performance. Mortality was measured as the osteoarthritis group effect on survival time in years. Results: More individuals with symptomatic osteoarthritis reported at least monthly falls compared to the other groups (14.5% vs. 7.2% without reported osteoarthritis and 8.4% asymptomatic/minimal osteoarthritis, p = 0.0004). The symptomatic group contained significantly more individuals with low functional mobility (TUG≥12 seconds) at baseline (51.5% vs. 29.0% and 36.1%, p < 0.0001). The odds of having low functional mobility for individuals with symptomatic osteoarthritis was 1.63 times compared to those without reported osteoarthritis (p < 0.0004); and was 1.57 times compared to those with asymptomatic/minimal osteoarthritis (p = 0.0026) after controlling pre-specified covariates. Similar results hold at the time of follow-up while changes in functional mobility were not significant across groups, suggesting that osteoarthritis likely does not accelerate the changes in functional mobility across time. Coexisting symptomatic osteoarthritis and Parkinson’s disease seem to additively increase the risk of mortality (p = 0.007). Conclusion: Our results highlight the impact and potential additive effects of symptomatic osteoarthritis in persons with Parkinson’s disease.

Factors Influencing Academic Stress on Students of University of Economics and Business - Vietnam National University

2020 ◽  
Vol 36 (3) ◽  
Author(s):  
Nham Phong Tuan ◽  
Nguyen Ngoc Quy ◽  
Nguyen Thi Thanh Huyen ◽  
Hong Tra My ◽  
Tran Nhu Phu
Keyword(s):  
Academic Stress ◽  
Stress Factors ◽  
Negative Effects ◽  
Cross Sectional ◽  
Stress Scale ◽  
Perceptions And Attitudes ◽  
National University ◽  
Questionnaire Surveys ◽  
The University ◽  
The Impact

The objective of this study is to investigate the impact of seven factors causing academic stress on students of University of Economics and Business - Vietnam National University: Lack of leisure time, Academic performance, Fear of failure, Academic overload, Finances, Competition between students, Relationships with university faculty. Based on the results of a practical survey of 185 students who are attending any courses at the University of Economics and Business - Vietnam National University, the study assesses the impact of stress factors on students. The thesis focuses on clarifying the concept of "stress" and the stress level of students, while pointing out its negative effects on students. This study includes two cross-sectional questionnaire surveys. The first survey uses a set of 16 questions to assess students’ perceptions and attitudes based on an instrument to measure academic stress - Educational Stress Scale for Adolescents (ESSA). The second survey aims to test internal consistency, the robustness of the previously established 7-factor structure. Henceforth, the model was brought back and used qualitatively, combined with Cronbach’s Alpha measurement test and EFA discovery factor analysis. This study was conducted from October 2019 to December 2019. From these practical analyzes, several proposals were made for the society, the school and the students themselves.

The impact of the use of a footrest on the quality of chest compressions. A prospective, randomized, cross-sectional study

2018 ◽  
Vol 31 (3) ◽  
Author(s):  
Jolanta Majer ◽  
Sandra Pyda ◽  
Jerzy Robert Ladny ◽  
Antonio Rodriguez-Nunez ◽  
Lukasz Szarpak
Keyword(s):  
Cross Sectional Study ◽  
Sectional Study ◽  
Chest Compressions ◽  
Cross Sectional ◽  
The Impact

Awareness of symptomatic differences Covid-19, SARS, Swine Flu, Common cold among dental students

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 1026-1033
Author(s):  
Nivedha Valliammai Mahalingam ◽  
Abilasha R ◽  
Kavitha S
Keyword(s):  
Infectious Diseases ◽  
Undergraduate Students ◽  
Common Cold ◽  
Emerging Infectious Diseases ◽  
Dental Students ◽  
Swine Flu ◽  
Viral Diseases ◽  
Surveillance Systems ◽  
Cross Sectional ◽  
The Impact

Enormous successes have been obtained against the control of major epidemic diseases, such as SARS, MERS, Ebola, Swine Flu in the past. Dynamic interplay of biological, socio-cultural and ecological factors, together with novel aspects of human-animal interphase, pose additional challenges with respect to the emergence of infectious diseases. The important challenges faced in the control and prevention of emerging and re-emerging infectious diseases range from understanding the impact of factors that are necessary for the emergence, to development of strengthened surveillance systems that can mitigate human suffering and death. The aim of the current study is to assess the awareness of symptomatic differences between viral diseases like COVID-19, SARS, Swine flu and common cold among dental students that support the prevention of emergence or re-emergence. Cross-sectional type of study conducted among the undergraduate students comprising 100 Subjects. A questionnaire comprising 15 questions in total were framed, and responses were collected in Google forms in SPSS Software statistical analysis. The study has concluded that dental students have an awareness of the symptomatic differences between infectious viral disease. The study concluded that the awareness of symptomatic differences between viral diseases like COVID-19, SARS, Swine flu, Common cold is good among the dental students who would pave the way for early diagnosis and avoid spreading of such diseases. A further awareness can be created by regular webinars, seminars and brainstorming sessions among these healthcare professionals.

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