scholarly journals Pattern of Growth of Sapwood, Heartwood, and Stem Volume of Open-Grown Eastern Redcedar in Grasslands

1998 ◽  
Vol 22 (3) ◽  
pp. 169-174 ◽  
Author(s):  
Dejene Alemayehu ◽  
David M. Engle ◽  
Robert F. Wittwer ◽  
Steve Anderson
Keyword(s):  
Control Measures ◽  
Tree Age ◽  
Stem Volume ◽  
Juniperus Virginiana ◽  
Exponential Rate ◽  
Eastern Redcedar ◽  
Commercial Harvest ◽  
Management Alternative ◽  
Relationship Of ◽  
The Relationship

Abstract The relationship of sapwood width, heartwood width, and stem volume with tree age was studied in 141 open-grown eastern redcedar (Juniperus virginiana L.) trees in central, eastern, and western Oklahoma. The rate of growth of sapwood and heartwood and the increase in stem volume were slow up to 15 to 20 yr of age and increased thereafter at an exponential rate until about age 27. These data reinforce the recommendation that control measures applied to invading eastern redcedar should be taken when the trees are less than about 10 yr old or less than 2 m tall. Allowing the trees to grow for commercial harvest may present a management alternative after the trees are 15 to 20 yr old. South. J. Appl. For. 22(3):169-174.

Application of Catastrophe Theory in Traffic Flow of Highway Tunnel Group

2013 ◽  
Vol 734-737 ◽  
pp. 1609-1612
Author(s):  
Wei Zhan ◽  
Yue Quan Shang ◽  
Feng Xia Chi
Keyword(s):  
Traffic Flow ◽  
Traffic Control ◽  
Catastrophe Theory ◽  
Critical Density ◽  
Flow Characteristics ◽  
Control Measures ◽  
Highway Tunnel ◽  
Relationship Of ◽  
The Relationship ◽  
Highway Management

Based on the investigation of traffic flow in a typical highway tunnel group, the traffic flow characteristics were analyzed by catastrophe theory with the relationship of the speed, volume and density. The discontinuous leaping change phenomenon of the traffic data under large traffic volume is better explained by the catastrophe model than the traditional ways. The value of critical density can be obtained by analyzing the critical state of traffic flow. Then the traffic flow warning can be realized in highway tunnel group region. The data and results can be used for the reference of taking traffic control measures by highway management.

scholarly journals Avirulence gene based RFLP and rep-PCR distinguish the genetic variation of Xanthomonas oryzae pv. oryzae pathotypes in Bangladesh

2022 ◽  
Vol 9 (1) ◽  
pp. 29-40
Author(s):  
Mohammad Mahbubul Haque ◽  
Md. Mostafa Masud ◽  
Samrin Bashar ◽  
Mohammad Iqbal Hossain ◽  
Md. Zahangir Alam ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Bacterial Blight ◽  
Phylogenetic Analyses ◽  
Control Measures ◽  
Avirulence Gene ◽  
Effective Control ◽  
Repeat Domain ◽  
Relationship Of ◽  
The Relationship ◽  
Pcr Techniques

Bacterial blight (BB) caused by X. oryzae pv. oryzae is one of the devastating diseases of rice mostly in Asia. Genomes of X. oryzae pv. oryzae is highly variable due to rearrangement of the large contents of transposable elements and dynamic changes of X. oryzae pv. oryzae population regulated efficiency of the control measures used for BB management of rice worldwide. In this study, genetic variation of X. oryzae pv. oryzae pathotypes of Bangladesh was studied using aviruelnce gene based RFLP and rep-PCR techniques aimed to formulate pathogen targeted effective control measures against BB of rice. Eight pathotypes of X. oryzae pv. oryzae field isolates were identified based on their reactions against 10 Near Isogenic Lines (NILs). Among eight pathotypes, pathotypes IV and V contained higher number of isolates which were 30.13% and 23.01% respectively while pathotype VIII revealed as minimum containing only 2.51% of total isolates. These eight pathotypes were studied for their genetic variation by RFLP using avrBs3 repeat domain as probe. The results conceded that Bangladeshi X. oryzae pv. oryzae strains seem carrying a minimum of two and maximum of nine avrBs3 family genes homologs. The resistance phenotype on IRBB7 and IRBB10 NILs also indicated presence of two major avrBs3 family genes viz. avrxa7 and avrXa10 in some pathotypes. Relationship of phylogenicity exhibited that X. oryzae pv. oryzae pathotypes assorted into two RFLP haplotypes as well as these haplotypes are largely distributed in Bangladesh. Phylogenetic analyses carried out by (REP, ERIC), rep-PCR and BOX depicted the presence of two main molecular haplotypes of X. oryzae pv. oryzae pathotypes. The relationship between pathotypes and molecular haplotypes of X. oryzae pv. oryzae in Bangladesh indicated that the same lineage possesses different pathotypes and different lineage possesses different pathotypes. The results indicated that eight different pathotypes might have originated from common inherited haplotypes with a wide genetic variation.

scholarly journals Expansion of Eastern Redcedar (Juniperus virginiana L.) into the Deciduous Woodlands within the Forest–Prairie Ecotone of Kansas

Forests ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 154 ◽  
Author(s):  
G. A. Pabodha Galgamuwa ◽  
Jida Wang ◽  
Charles J. Barden
Keyword(s):  
Temporal Dynamics ◽  
Control Measures ◽  
Rapid Expansion ◽  
Deciduous Forests ◽  
Support Vector ◽  
Juniperus Virginiana ◽  
Eastern Redcedar ◽  
Growing Stock ◽  
Quercus Species ◽  
Spatio Temporal

North America’s midcontinent forest–prairie ecotone is currently exhibiting extensive eastern redcedar (ERC) (Juniperus virginiana L.) encroachment. Rapid expansion of ERC has major impacts on the species composition and forest structure within this region and suppresses previously dominant oak (Quercus) species. In Kansas, the growing-stock volume of ERC increased by 15,000% during 1965–2010. The overarching goal of this study was to evaluate the spatio-temporal dynamics of ERC in the forest–prairie ecotone of Kansas and understand its effects on deciduous forests. This was achieved through two specific objectives: (i) characterize an effective image classification approach to map ERC expansion, and (ii) assess ERC expansion between 1986 and 2017 in three study areas within the forest–prairie ecotone of Kansas, and especially expansion into deciduous forests. The analysis was based on satellite imagery acquired by Landsat TM and OLI sensors during 1986–2017. The use of multi-seasonal layer-stacks with a Support Vector Machine (SVM)-supervised classification was found to be the most effective approach to classify ERC distribution with high accuracy. The overall accuracies for the change maps generated for the three study areas ranged between 0.95 (95 CI: ±0.02) and 0.96 (±0.03). The total ERC cover increased in excess of 6000 acres in each study area during the 30-year period. The estimated percent increase of ERC cover was 139%, 539%, and 283% for the Tuttle Creek reservoir, Perry reservoir, and Bourbon County north study areas, respectively. This astounding rate of expansion had significant impacts on the deciduous forests where the conversion of deciduous woodlands to ERC, as a percentage of the total encroachment, were 48%, 56%, and 71%, for the Tuttle Creek reservoir, Perry reservoir, and Bourbon County north study areas, respectively. These results strongly affirm that control measures should be implemented immediately to restore the threatened deciduous woodlands of the region.

scholarly journals Impact of Pruning Eastern Redcedar (Juniperus virginiana)

2002 ◽  
Vol 17 (4) ◽  
pp. 189-193 ◽  
Author(s):  
Thomas L. Schmidt ◽  
Tom D. Wardle
Keyword(s):  
South Dakota ◽  
Great Plains ◽  
Wood Quality ◽  
Ground Level ◽  
Control Measures ◽  
Juniperus Virginiana ◽  
Eastern Redcedar ◽  
Total Height ◽  
Forest Industries ◽  
Future Utilization

Abstract In recent years, eastern redcedar has been the most rapidly expanding tree resource in the Great Plains from Oklahoma to South Dakota, primarily in rangelands and pastures. Based on these increases and potential management-related problems, eastern redcedar is perceived as a threat to the rangeland resource. Pruning eastern redcedar can allow for increased herbaceous growth under the eastern redcedar's crown, improve livestock handling, maintain the species for diversity and habitat contributions, and improve wood quality for potential future utilization by forest industries. To determine the effect of pruning to different heights on tree growth, we compared unpruned trees' total height and diameter to trees pruned from ground level to heights of 60, 90, 120, and 150 cm. No significant differences in the total height were found for all pruning treatments over all time periods. After more than 10 yr, trees pruned to 60, 90, and 120 cm had smaller diameters at ground level than unpruned trees. There were no differences in ground diameters for trees pruned to 150 cm compared to unpruned trees after 4 yr of growth. There were no significant differences in dbh for eastern redcedar trees pruned to all heights. Management of eastern redcedar, including pruning, is recommended as an alternative to control measures. West. J. Appl. For. 17(4):189–193.

Generalized Locus of Control and Health Locus of Control of Surgical Patients

1983 ◽  
Vol 52 (2) ◽  
pp. 599-602 ◽  
Author(s):  
Judy Larde ◽  
James R. Clopton
Keyword(s):  
Locus Of Control ◽  
Health Locus Of Control ◽  
Control Measures ◽  
Control Beliefs ◽  
Alternate Forms ◽  
Multidimensional Health ◽  
Relationship Of ◽  
The Relationship ◽  
Larger Sample ◽  
Specific Health

The relationship of generalized locus of control expectancies and specific health locus of control beliefs was explored in a sample of 24 cholecystectomy patients prior to surgery. The Internality, Powerful Others, and Chance scales were used to assess generalized locus of control expectancies, and specific health locus of control beliefs were assessed by the Multidimensional Health Locus of Control scales. The results question the theoretical commonality between the two locus of control measures and suggest that the alternate forms of the health locus of control scales are not equivalent. Cross-validation on a larger sample is required.

scholarly journals The method of determining the silvicultural and inventory indices of urban spaces with the use of the equations of communication

2018 ◽  
Vol 7 (4) ◽  
pp. 82-90
Author(s):  
Василий Ковязин ◽  
Vasiliy Kovyazin ◽  
Тхи Нгуен ◽  
Thi Nguen
Keyword(s):  
Species Diversity ◽  
Tree Species ◽  
Forest Inventory ◽  
Urban Spaces ◽  
Tree Age ◽  
Coefficient Of Determination ◽  
Relationship Of ◽  
First Time ◽  
The Relationship ◽  
Trees And Shrubs

The purpose of our research was to study the species diversity of trees and shrubs in the memorial Park across three centuries after its formation. Such research we carried out for the first time. In addition, we conducted measurements of forest inventory indices of the studied tree species. The calculated equation of the relationship of tree age with a height and diameter that can be measured. The mathematical models should be used to determine the age of trees, as the drill age is not recommended to use for traditional purposes in the memorial parks. The tightness of the obtained relations inventory indices in the form of a parabola is quite high. The coefficient of determination is 0.82 to 0.99, depending on the type of wood.

scholarly journals Parasites in fisheries and mariculture

Parasitology ◽  
2015 ◽  
Vol 142 (1) ◽  
pp. 1-4 ◽  
Author(s):  
J. T. TIMI ◽  
K. MACKENZIE
Keyword(s):  
Control Measures ◽  
Natural Environments ◽  
Parasite Control ◽  
Controlled Systems ◽  
Marine Realm ◽  
Control And Management ◽  
And Control ◽  
Relationship Of ◽  
The Relationship ◽  
Harmful Effects

Traditionally, parasitology has been concerned with the harmful effects of parasitic organisms; it is basically an applied science. Since its founding in the field of medicine, and later in veterinary medicine, parasitology has been mainly devoted to generating knowledge, which is applicable to parasite control and management, and eventually to their eradication. However, the complexity of parasitism, as revealed over recent decades by workers in various specialisms of parasitology, makes the application of management and control measures very difficult in natural environments. This is particularly true in the marine realm, where however some applied aspects of parasitology, other than those devoted to control and management of parasites, have been shown to be of great importance for fisheries, human health, biological control of introduced species and environmental sciences (Rohde, 2002). The relationship of parasitology with mariculture practices, which are carried out mostly on artificial and controlled systems, follows a more classical approach, focusing on the development of strategies of prevention, management and control of pathogens.

scholarly journals Relationship of necrotic disease of beech trunks to the sociological position of trees in the stand

2019 ◽  
Vol 48 (No. 5) ◽  
pp. 225-229 ◽  
Author(s):  
A. Cicák ◽  
I. Mihál
Keyword(s):  
Slovak Republic ◽  
Point Of View ◽  
Tree Age ◽  
Age Classes ◽  
Age Class ◽  
Individual Trees ◽  
Relationship Of ◽  
The Relationship

The authors analyse the results of investigations into the degree of necrotic damage of beech bark carried out in the whole territory of the Slovak Republic. The aim of these analyses is to answer a question about the relationship between the degree of necrotic damage of beech trunks and sociological position of trees in the stands studied. In the years 1995–2001, the degree of necrotic damage by tracheomycotic type to 6,579 beech trunks was evaluated in 54 selected localities in 33 orographic units. The lowest frequency (4.3%) of trees showing the 3rd and 4th degree of necrotic damage was found in the 1st tree age class. The frequency of damaged trees increased proportionally with the worsening sociological position of trees. The values of the index of trunk necrotisation (INK) increased from 0.71 in the 1st tree age class to 2.14 in the 5<sup>th</sup> tree age class. It also corresponded with dynamics of disease frequency in the tree age classes. The authors found that the extent of necrotic disease of beech trunks expressed by INK was signifi cantly infl uenced by the sociological position of individual trees in the stand. They conclude that strongly infected trees of the 4th and 5<sup>th</sup> tree age class left in the stands is problematic from the phytopathological point of view. Such trees left in the stands may cause a serious epiphytotic because these trees are one of the infection sources ot the necrotic disease.

scholarly journals Vegetative Propagation of Eastern Redcedar by Stem Cuttings

HortScience ◽  
1992 ◽  
Vol 27 (12) ◽  
pp. 1272-1274 ◽  
Author(s):  
Paul H. Henry ◽  
Frank A. Blazich ◽  
L. Eric Hinesley
Keyword(s):  
Adventitious Rooting ◽  
Tree Age ◽  
Juniperus Virginiana ◽  
Stem Cuttings ◽  
Stock Plant ◽  
Eastern Redcedar ◽  
Crown Position ◽  
Cutting Length ◽  
Position Type ◽  
Old Trees

Studies were conducted to investigate the effects of season (timing), IBA application, genotype, crown position, type of cutting (straight vs. heel), cutting length, and stock plant age upon adventitious rooting of stem cuttings of eastern redcedar (Juniperus virginiana L.). Genotype had a strong influence on percent rooting, root count, and root length of 4-year-old trees. With trees of this age, percent rooting was maximized (87%) with hardwood cuttings taken in January and treated with 5000 ppm IBA. Crown position from which cuttings were collected did not influence rooting. Straight cuttings, with or without a light wound, rooted at a significantly higher percentage (78%) than heel cuttings (52%). With 30-year-old trees, cuttings from the lower third of the crown rooted at a significantly higher percentage (67%) than cuttings from the middle third (43%). Better rooting was obtained with straight (68%) than heel (47%) cuttings. Cutting length affected rooting, with root count and length highest in longer cuttings. Increased tree age reduced rooting, although cuttings from 40-year-old trees retained substantial rooting capacity. Chemical name used: 1 H-indole-3-butyric acid (IBA).

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