scholarly journals Biomass Allocation and Carbon Stock in Elm (Ulmus Wallichiana Planch) Plantation

2017 ◽  
Vol 12 (2) ◽  
pp. 339-344
Author(s):  
Shabir Rather ◽  
K.N. Qaisar ◽  
Sabeena Nabi ◽  
R. Banyal ◽  
P.A. Khan ◽  
...  
Keyword(s):  
Biomass Allocation ◽  
Carbon Stock ◽  
Growth Parameters ◽  
Stem Volume ◽  
Maximum Height ◽  
Total Biomass ◽  
Diameter Class ◽  
Increase With Increase ◽  
Significant Difference ◽  
Diameter Classes

The present investigation was conducted on a 22- year old Elm plantation established at Wadura campus of SKUAST-Kashmir. Four diameter classes viz., D1 (5-10cm), D2 (10-15cm), D3 (15-20cm) and D4 (>20cm) were stratified from the plantation and 24 trees (6 from each diameter class) were randomly selected and felled in the year 2015. The growth parameters of the trees increased with increase in the diameter class. The maximum height, dbh, basal area and stem volume were 14.98m, 23.77cm, 0.044m2 and 0.400m3, respectively. Biomass per tree of all tree components viz., stem, branches, foliage and roots showed significant increase with increase in the diameter of the trees. The total biomass, carbon stock and carbon dioxide equivalent increased from lower to higher diameter classes. The highest values observed for these parameters were 475.54 kg/tree (fresh), 148.59 kg/tree and 543.82 kg/tree, respectively under D4 diameter class. The biomass allocation coefficient of branch and root (BACb and BACr) attained higher values in lower diameter classes. The maximum and minimum values of these coefficients were 0.158 and 0.085; 0.298 and 0.278, respectively under D1 and D4 diameter classes. The size of trees did not produce significant effect on the biomass allocation coefficient of foliage (BACf). The diameter of the trees produced non-significant difference in the growth efficiency (GE) of different tree components.

scholarly journals Vegetative Propagation of Balanites aegyptiaca (L.) Del. by Air Layering under Sahelian Climate in Niger

2019 ◽  
pp. 1-10
Author(s):  
Maman Kamal Abdou Habou ◽  
Habou Rabiou ◽  
Laouali Abdou ◽  
Boubacar Moussa Mamoudou ◽  
Ismaël Bio Yandou` ◽  
...  
Keyword(s):  
Survival Rate ◽  
Vegetative Propagation ◽  
Diameter Class ◽  
Balanites Aegyptiaca ◽  
Fruit Species ◽  
Average Survival ◽  
Significant Difference ◽  
Class 1 ◽  
Average Survival Rate ◽  
Diameter Classes

Balanites aegyptiaca (L.) Del. is a fruit species from the Sahelian and Sudano-sahelian zones, highly appreciated by the population. It provides a source of income for the rural population and its various parts are used for human and animal food, handicrafts and traditional medicine. However, the lack of data on propagation techniques of the species is a significant limitation to its domestication. This study aims to evaluate the vegetative propagation capacity of Balanites aegyptiaca by air layering. The trials were conducted in the Arboretum of Sahara Sahel Foods in Zinder, Niger. The layers were placed on orthotropic branches. The variables selected were the diameter class (1-2 cm, 2-3 cm and 3-4 cm) and the substrates (sand+manure, sand+sawdust and sand). A total of 116 layers were made. The results show that 93.1% of the layers have taken root two months after realization. The diameter classes and the three substrates have no significant influence on the number of roots. In contrast, root length varied significantly with substrates (P = 0.000) and branch diameter classes (P = 0.031). As for the diameter of the newly formed roots, a significant difference was observed between the diameter classes and the substrates have no significant effect on this parameter. One month after weaning of layers, an average survival rate of 68.5% was obtained. The seedlings of the diameter class 2-3 cm have the highest survival rate (83.1%). These results suggest that it is possible to produce Balanites aegyptiaca plants by air layering, and could contribute to the development of strategies adapted to its domestication.

scholarly journals Influence of including maize offal in diets on growth, carcass composition and economics of Clarias gariepinus

2021 ◽  
Vol 14 (3) ◽  
pp. 027-035
Author(s):  
Sunday Kenneth Igbang ◽  
Ada Fidelis Bekeh ◽  
Ochang Stephen Ncha
Keyword(s):  
Growth Parameters ◽  
Control Diet ◽  
Clarias Gariepinus ◽  
Experimental Period ◽  
Carcass Composition ◽  
African Catfish ◽  
Feed Conversion ◽  
Increase With Increase ◽  
Significant Difference ◽  
The Hours

Aiming at finding cheaper and still efficient feed for aquaculture species 56 days feeding trial was conducted on African catfish (Clarias gariepinus) post fingerlings, fed on five diets with a 40% crude protein target in which maize was replaced with maize offal meal at 0%, 25%, 50%, 75%, and 100% respectively. Ten fish each were stocked in a plastic aquarium tank containing 20 L of water. The fish were fed at 5% body weight divided into two rations ginen at the hours of 8-8:30 am and 5-5:30pm. Growth parameters showed increase with increase in maize offal based diets, with observed weight gains of 72.42, 79.00, 95.92, 130.83 and 65.83 for diets 1, 2, 3, 4, and 5 respectively. Feed conversion ratio (recorded best in 75% maize offal based diet substitution, while the poorest was recorded at 25% maize offal diet replacement, followed by the control diet (100% maize diet). 75% maize offal replacement recorded the highest specific growth rate (p<0.05).There was significant difference (p<0.05) in the ash content, crude fiber and energy level in the fish carcass. The cost of feed used throughout the experimental period was not significantly (p>0.05) influenced by the increasing level of maize offal as a replacement for maize in the diets, as the costs were comparable. However, this study reveals that maize offal meal can successfully replaced maize up to 75% in the diet of Clarias gariepinus post fingerlings without adverse effect on growth, carcass composition and economics.

scholarly journals Stacked volume conversion factor for geometric volume of Eucalyptus sp.

2019 ◽  
Vol 13 ◽  
pp. 46
Author(s):  
André Salgado De Andrade Sandim ◽  
Ariadna Coelho Mota ◽  
Mario Lima Dos Santos ◽  
Welton Dos Santos Barros ◽  
Beatriz Cordeiro Costa ◽  
...  
Keyword(s):  
Conversion Factor ◽  
Diameter Class ◽  
Wood Volume ◽  
Conversion Factors ◽  
Mean Values ◽  
Significant Difference ◽  
Clonal Plantation ◽  
Real Value ◽  
Different Diameters ◽  
Diameter Classes

Post-harvest, wood volume can be calculated with a stacking factor which can be influenced by diameter classes involved. Consequently, the following question arises: there is a difference between the volume conversion factor for stacked to geometric volume between piles of clonal plantation logs of different diameters classes? The hypothesis is: if smaller logs have a higher stacked to geometric volume conversion factor, between-log voids will be smaller and the overall stacks will therefore have lower volumes. Therefore, the objective of this study was to compare stacking and cubing factors in stacks of logs with different diameters for two Eucalyptus sp. clones. The study was conducted in Barra do Corda municipality, Maranhão State, Brazil. Timber was laid in piles of logs by diameter class, composed of logs of smaller (9-10.99 cm) and larger (11-13 cm) diameters. Stacking factor means for clone 1 were 1.88 for the larger diameter and 2.00 for the smaller diameter class, while for clone 2 mean values were 1.62 and 1.65, for stacks with larger and smaller diameter classes, respectively. For logs from the same clone there was no significant difference for the conversion factors between the stacks with the largest and smallest diameter. However, there was a significant difference in the conversion factors between the two clones, proving the hypothesis tested. Thus, for each genetic lineage, a proper stacking factor must be established so that the estimated volume comes close to the real value.

scholarly journals Vegetative Propagation Trial of Prosopis africana (Guill. et Perr.) Taub. by Air Layering under Sudano-Sahelian Climate in the South-Central Niger

2015 ◽  
Vol 2015 ◽  
pp. 1-6
Author(s):  
Laouali Abdou ◽  
Saley Karim ◽  
Rabiou Habou ◽  
Ali Mahamane
Keyword(s):  
Vegetative Propagation ◽  
Germination Rate ◽  
The South ◽  
Diameter Class ◽  
South Central ◽  
Significant Difference ◽  
Wood Debris ◽  
Prosopis Africana ◽  
Black Plastic ◽  
Diameter Classes

Prosopis africana is a species of great socioeconomic importance but threatened with extinction in Niger because of overuse and regeneration problem. This study, conducted in the Maradi (Niger) area, precisely at El Gueza in the south of Gazaoua department, aims to evaluate the vegetative propagation capacity of P. africana by air layering under the Sudano-Sahelian climate of the south-central Niger. A ring of bark was taken on each selected branch and the wound was covered with a black plastic filled with a damp mixture of soil and wood debris. The chosen parameters are the diameter class and the position on the branch. In all, 60 branches were treated and followed for 130 days: 28.33% produced shoots and there was no significant difference between the diameter classes and between the positions. These results show that propagating trees of the species by air layering is possible and this technique can be used to multiply and keep this species, which will reduce the regeneration problem linked to a low seed germination rate.

scholarly journals Investigating the out-of-roundness and pith-off-centre in stems of three broadleaved species in Hyrcanian forests

2012 ◽  
Vol 58 (No. 11) ◽  
pp. 513-518 ◽  
Author(s):  
A. Fallah ◽  
N. Riahifar ◽  
K. Barari ◽  
A. Parsakhoo
Keyword(s):  
Stem Diameter ◽  
Diameter Class ◽  
Hyrcanian Forests ◽  
Breast Height ◽  
Significant Difference ◽  
Alnus Subcordata ◽  
Pith Eccentricity ◽  
Diameter Classes

The out-of-roundness and pith-off-centre of Alnus subcordata, Acer velutinum and Quercus castaneifolia growing in Hyrcanian forests of Iran were investigated. Stem disks were cut from the breast height and stump height of felled trees in diameter classes of 20 cm to 90 cm. Results indicated that the pith eccentricity for Acer velutinum was significantly greater than that of Alnus subcordata and Quercus castaneifolia (P &lt; 0.01). The pith-off-centre significantly increased with increasing stem diameter from 20 cm to 50 cm, while no significant difference were observed for pith-off-centre index from diameter class of 55 cm to 90 cm. The out-of-roundness in stems of Acer velutinum and Alnus subcordata was significantly greater than that of Quercus castaneifolia (P &lt; 0.01). Moreover, out-of-roundness significantly decreased with increasing stem diameters from 20 cm to 45 cm except for 35 cm. There were no significant differences among diameter classes from 60 cm to 85 cm with respect to out-of-roundness. For all the species, the out-of-roundness and pith-off-centre at stump height were greater than those at breast height.

Interactive effects of carbon dioxide concentration and light on the morphological and biomass characteristics of black spruce and white spruce seedlings

Botany ◽  
2009 ◽  
Vol 87 (1) ◽  
pp. 67-77 ◽  
Author(s):  
Jacob Marfo ◽  
Qing-Lai Dang
Keyword(s):  
Picea Glauca ◽  
Black Spruce ◽  
Carbon Dioxide Concentration ◽  
White Spruce ◽  
Interactive Effects ◽  
Stem Volume ◽  
Total Biomass ◽  
Root Mass ◽  
Significant Difference ◽  
Collar Diameter

CO2–light interactions can influence the competition among boreal plants, but are poorly understood. We investigated the effect of such interactions on the growth and biomass of 1-year-old black spruce (Sb) ( Picea mariana (Mill.) BSP) and white spruce (Sw) ( Picea glauca (Moench) Voss) grown with CO2 concentrations ([CO2]) of 360 and 720 µmol·mol–1 under 30%, 50%, and 100% light, in greenhouses. There were significant two-way and three-way interactions. Root collar diameter (RCD) of Sw decreased with decreasing light, while in Sb, there was no significant difference in RCD for plants grown under 50% or 30% light. Height was greater for plants grown under 100% light than if the plants were shaded. Elevated [CO2] increased RCD by 33% and enhanced stem volume by 67%, 98%, and 84% under 100%, 50%, and 30% light, respectively. The CO2 enhancement of total biomass was relatively higher under lower light, and greater for Sb than Sw. Elevated [CO2] decreased specific leaf area under 50% light only. Root mass was generally higher under 100% light than when shaded. Elevated [CO2] increased the root mass of Sb under 100% light, but decreased it under 30% light. Elevated [CO2] decreased the shoot/root ratio under 100% light, but increased it under 30% light. Our data suggest that raising [CO2] will likely increase species competitiveness under low light conditions, and that the increase will be greater in species that are relatively shade tolerant.

scholarly journals Cerebellum and brain stem volume loss in relapsing remission multiple sclerosis by MRI volumetry: relation to neurological disability score and number of relapses

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Magdy Elzayady ◽  
Naglaa Lotfy Debees ◽  
Mohamed Khalil ◽  
Mohammed Mahmoud Dawoud
Keyword(s):  
Brain Stem ◽  
Tissue Loss ◽  
Cerebellar Hemisphere ◽  
Stem Volume ◽  
Volume Loss ◽  
Neurological Disability ◽  
Disability Score ◽  
Brain Volume Loss ◽  
Significant Difference ◽  
Mri Volumetry

Abstract Background MRI is the method of choice in the diagnosis of MS as well as in monitoring the disease activity. MRI volumetry is used to assess whole or regional brain volume loss which reflects neurodegenerative aspect of the disease and plays an important role in all stages of disease. The aim of this work is to study MRI volumetry in the evaluation of cerebellum and brain stem volume loss in RRMS patients and its correlation with neurological disability score and number of relapses. Results Volumes of whole brainstem, medulla, and pons showed a significant decrease in RRMS cases compared to controls (p < 0.05). Brainstem volume had a mean volume of 22.17 and 25.09 cm3 in cases and controls, respectively. However, midbrain volume showed no significant difference between cases and controls (p = 0.134). Volume of left cerebellar cortex showed a significant decrease in RRMS cases compared to controls (p < 0.001). It had mean volumes of 81.64 and 92.14 ml in cases and controls, respectively, at left cerebellar hemisphere, while right cerebellar hemisphere cortex volumes were 80.37 and 91.97 ml in cases and controls, respectively. Cerebellar white matter showed no significant volume decrease in cases and controls. Conclusion Volumetric MR imaging is an important tool for quantifying the MS disease, assesses MS activity, progression, and tissue loss. The degree and the pattern of atrophy on MRI images correlate significantly with the neurological disability score and number of relapses.

scholarly journals Revealing Changes in the Stem Form and Volume Allocation in Diverse Boreal Forests Using Two-Date Terrestrial Laser Scanning

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 835
Author(s):  
Ville Luoma ◽  
Tuomas Yrttimaa ◽  
Ville Kankare ◽  
Ninni Saarinen ◽  
Jiri Pyörälä ◽  
...  
Keyword(s):  
Tree Growth ◽  
Point Cloud ◽  
Laser Scanning ◽  
Terrestrial Laser Scanning ◽  
Point Clouds ◽  
Stem Volume ◽  
Accurate Information ◽  
Stem Form ◽  
Monitoring Period ◽  
Significant Difference

Tree growth is a multidimensional process that is affected by several factors. There is a continuous demand for improved information on tree growth and the ecological traits controlling it. This study aims at providing new approaches to improve ecological understanding of tree growth by the means of terrestrial laser scanning (TLS). Changes in tree stem form and stem volume allocation were investigated during a five-year monitoring period. In total, a selection of attributes from 736 trees from 37 sample plots representing different forest structures were extracted from taper curves derived from two-date TLS point clouds. The results of this study showed the capability of point cloud-based methods in detecting changes in the stem form and volume allocation. In addition, the results showed a significant difference between different forest structures in how relative stem volume and logwood volume increased during the monitoring period. Along with contributing to providing more accurate information for monitoring purposes in general, the findings of this study showed the ability and many possibilities of point cloud-based method to characterize changes in living organisms in particular, which further promote the feasibility of using point clouds as an observation method also in ecological studies.

scholarly journals Optimizing hydroponic culture media and NO3−/NH4+ ratio for improving essential oil compositions of purple coneflower (Echinacea purpurea L.)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fatemeh Ahmadi ◽  
Abbas Samadi ◽  
Ebrahim Sepehr ◽  
Amir Rahimi ◽  
Sergey Shabala
Keyword(s):  
Particle Size ◽  
Essential Oil ◽  
Plant Growth ◽  
Plant Height ◽  
Growth Parameters ◽  
Echinacea Purpurea ◽  
Peat Moss ◽  
Root Weight ◽  
Total Biomass ◽  
Growing Media

AbstractMedicinal plants represent a valuable commodity due to beneficial effects of their natural products on human health, prompting a need for finding a way to optimize/increase their production. In this study, a novel growing media with various perlite particle size and its mixture with peat moss was tested for hydroponic-based production of Echinacea purpurea medicinal plant under greenhouse conditions. The plant growth parameters such as plant height, total fresh leave weight, fresh root weight, total biomass, total chlorophyll, leaf area, and essential oil compositions were assessed. Perlite particle size in the growing media was varied from very coarse (more than 2 mm) to very fine (less than 0.5 mm), and the ratio between perlite and peat moss varied from 50:50 v/v to 30:70 v/v. In addition, two nitrate (NO3−) to ammonium (NH4+) ratios (90:10 and 70:30) were tested for each growing media. The medium containing very fine-grade perlite and 50:50 v/v perlite to peat moss ratio was found to be most optimal and beneficial for E. purpurea performance, resulting in maximal plant height, fresh and dry weight, leaf surface area, and chlorophyll content. It was also found that an increase in NO3−/NH4+ ratio caused a significant increase in plant growth parameters and increase the plant essential oil content. The major terpene hydrocarbons found in extract of E. purpurea with the best growth parameters were germacrene D (51%), myrcene (15%), α-pinene (12%), β-caryophyllene (11%), and 1-Pentadecene (4.4%), respectively. The percentages of these terpene hydrocarbons were increased by increasing of NO3−/NH4+ ratio. It can be concluded that decreasing the perlite particle size and increasing the NO3−/NH4+ ratio increased the plant growth parameters and essential oil compositions in E. purpurea.

Growth and movement of the South African abalone Haliotis midae: A reassessment

1995 ◽  
Vol 46 (3) ◽  
pp. 583 ◽  
Author(s):  
RJQ Tarr
Keyword(s):  
South African ◽  
Growth Rates ◽  
Growth Parameters ◽  
Eastern Coast ◽  
Island Population ◽  
Western Coast ◽  
Eastern Cape ◽  
The South ◽  
Significant Difference ◽  
Haliotis Midae

Growth rates of a number of Haliotis midae populations around the South African coast were studied by means of tagging. These populations ranged from the cool waters of the western coast to the more temperate environment of the eastern Cape. Standard von Bertalanffy growth curves were fitted and growth parameters derived. These ranged from 0.19 to 0.25 for K, the average rate at which L∞ is approached, and from 156 to 173 for L∞, the average theoretical maximum length. These indicate far higher growth rates than were previously published for this commercially fished species, and the reasons for this difference are discussed. The expectation that growth rates would be fastest in the warmer eastern Cape waters was not realized, there being no significant difference in growth between the Bird Island population on the eastern coast and the Robben Island population on the western coast. These new growth parameters indicate that H. midae in the commercial fishery grounds is attaining sexual maturity some four years earlier, and the minimum legal size some five years earlier, than previously considered. This has considerable significance for modelling studies presently underway. Movement of a small population of adult H. midae was studied over a three-year period, after which 47% of the original abalone were still present on the study site. Of these, 81.5% still occupied exactly the same position on the rocks. This indicates that H. midae that have located an optimum habitat, and that are not disturbed, tend not to move.

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