Identification de descripteurs morphométriques sensibles aux conditions générales de croissance des semis de chêne rouge [Quercusrubra) en milieu naturel

1995 ◽  
Vol 25 (1) ◽  
pp. 157-165 ◽  
Author(s):  
J. Trencia
Keyword(s):  
Laboratory Experiments ◽  
Specific Root Length ◽  
Dry Mass ◽  
Growth Conditions ◽  
Quebec City ◽  
Mass Ratio ◽  
City Region ◽  
Stem Height ◽  
Annual Increment ◽  
Mean Annual Increment

Red oak (Quertusrubra L.) seedlings measuring less than 1 m in height were collected from seven sites in the Québec City region. The sites were grouped according to pedology, dendrometry, and phytosociology. The object of this study was to select morphometric characteristics that are most sensitive to global differences in growth conditions. Most of the variables studied are frequently used to assess seedling performance in greenhouse or laboratory experiments. The characteristics measured included total stem height; mean annual increment of the biomass; number, mass, and length of the roots; shoot/root dry mass ratio; specific root length. Two topologic variables were also measured: the total external pathlength and the diameter of the root system, as defined by Fitter. The topologic variables and number of roots differentiated well the various groups of sites. Among the variables chosen, it is possible to estimate the value of the ones that are most difficult to assess, from less time-consuming variables.

scholarly journals Growth and Evaluation of Phenolic Compounds in Physalis angulata L. at Two Different Periods in the Bahia Reconcavo, Brazil

2017 ◽  
Vol 9 (10) ◽  
pp. 145
Author(s):  
Claudia Brito De Abreu ◽  
Manuela Oliveira De Souza ◽  
Fabrício Mendes Miranda ◽  
Torben Grael Dos Santos Rodrigues ◽  
Fabio De Souza Dias
Keyword(s):  
Phenolic Compounds ◽  
Leaf Area ◽  
Therapeutic Potential ◽  
Dry Mass ◽  
Mass Ratio ◽  
Stem Height ◽  
Study Region ◽  
Local Soil ◽  
Number Of Leaves ◽  
Physalis Angulata

Physalis angulata L. has aroused the interest of the researchers, since its properties come from the great therapeutic potential attributed to the commonly called substances of physalins. However, its cultivation in the study region lacks important information on the species adaptation to local soil and climate characteristics. The aim of this study was to evaluate the growth and concentration of phenolic compounds in P. angulata L. at two different periods in the Bahia Reconcavo. The experimental design was completely randomized blocks with 10 replicates. We evaluated the stem height and diameter, number of leaves and fruits, dry mass of leaves, stems and roots, leaf area, specific leaf area, leaf area ratio, leaf mass ratio and total phenolics, total flavonoids and antioxidant activity in the different organs of the plant. The growth was favorable from April to June. However, the concentration of phenolic compounds was higher in the period from December to February. The cultivation period influenced the growth and concentration of phenolic compounds in P. angulata L. in the Bahia Reconcavo.

Bioenergy yield of Eucalyptus urophylla clones and its relationship with the mean annual increment of wood volume

2021 ◽  
Author(s):  
Bruna Isabele Pinheiro da Silva ◽  
Alyne Chaveiro Santos ◽  
Macksuel Fernandes da Silva ◽  
Mariana Dianese Alves de Moraes ◽  
Carlos Roberto Sette Jr
Keyword(s):  
Energy Density ◽  
Basic Density ◽  
Dry Mass ◽  
Energy Yield ◽  
Eucalyptus Urophylla ◽  
Annual Increment ◽  
Wood Volume ◽  
Wood Basic Density ◽  
The Difference ◽  
Mean Annual Increment

This study aimed to evaluate the energy yield and wood characteristics of Eucalyptus urophylla clones with different mean annual increment of wood volume (MAI). The clones presented MAIs of 39.2, 54.1 and 70.0 m3 ha-1 yr-1 in the field experiment at six years after planting when the trees were cut down to evaluate the wood basic density and higher heating values. The energy density, dry mass and energy yield were estimated. The MAI of E. urophylla clones influenced the wood basic density, dry mass, and energy yield, but did not influence the higher heating value and energy density. Clone 3 had the highest MAI, and also had higher energy yield and dry mass, but lower wood basic density. The difference between the most and the least productive clones was 242,648 MJ ha-1 yr-1. The results reinforce the importance of evaluating the wood quantity production (MAI) to select Eucalyptus clones for energy purposes.

scholarly journals Computer Analysis of the Porous Structure of Activated Carbons Derived from Various Biomass Materials by Chemical Activation

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4121
Author(s):  
Mirosław Kwiatkowski ◽  
Elżbieta Broniek
Keyword(s):  
Porous Structure ◽  
Adsorption Isotherms ◽  
Computer Analysis ◽  
Activated Carbons ◽  
Chemical Activation ◽  
Adsorbed Layer ◽  
Dry Mass ◽  
Mass Ratio ◽  
Adsorption Volume ◽  
Homogeneous Surface

In this study, the preparation of activated carbons from various materials of biomass origin by activation with potassium hydroxide and a comprehensive computer analysis of their porous structure and adsorption properties based on benzene (C6H6) adsorption isotherms were carried out. In particular, the influence of the mass ratio of the activator’s dry mass to the char mass on the formation of the microporous structure of the obtained activated carbons was analysed. The summary of the analyses carried out based on benzene adsorption isotherms begged the conclusion that activated carbon with a maximum adsorption volume in the first adsorbed layer and homogeneous surface can be obtained from ebony wood at a mass ratio of the activator to the char of R = 3. The obtained results confirmed the superiority of the new numerical-clustering-based adsorption analysis (LBET) method over simple methods of porous structure analysis, such as the Brunauer–Emmett–Teller (BET) and Dubinin–Raduskevich (DR) methods. The LBET method is particularly useful in the evaluation of the influence of the methods and conditions of production of activated carbons on the formation of their porous structure. This method, together with an appropriate economic analysis, can help in the precise selection of methods and conditions for the process of obtaining activated carbons at specific manufacturing costs, and thus makes it possible to obtain materials that can successfully compete with those of other technologies used in industrial practice and everyday life.

Optimization of Growth Conditions of Citrus Anthracnose Agent Colletotrichum gloeosporioides Isolates in Tunisia

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Ben Hadj-Daoud H ◽  
◽  
Ben Salem I ◽  
Boughalleb-M’Hamdi N ◽  
◽  
...  
Keyword(s):  
Morphological Traits ◽  
Laboratory Experiments ◽  
Plant Pathogens ◽  
Colletotrichum Gloeosporioides ◽  
Optimal Growth ◽  
Growth Conditions ◽  
Fruit Drop ◽  
Nutritional Conditions ◽  
Solid Media ◽  
Wide Range

Background: Colletotrichum gloeosporioides is important plant pathogens on a wide range of plant hosts such as citrus causing pre- or post-harvest infections as anthracnose, post-bloom fruit drop, tearstain and stem-end rot on fruit, or wither-tip of twigs. Method: The optimization of growth conditions of this pathogen was performed (solid media, temperature, pH and water potential under laboratory experiments). Results: Our results revealed that the maximum radial growth of C. gloeosporioides was recorded on SDA medium. All isolates were able to grow on PDA at temperatures of 15 and 30°C (over 0.7cm/day). Optimal growth radial was recorded at pH 5, 6, 7 and 8. Similar responses were obtained with both salt types, but, in general, C. gloeosporioides was more tolerant to KCl than NaCl. Conclusion: Studies of cultural, morphological traits of the pathogen are prominent to understand the response of the pathogen in different environmental and nutritional conditions.

scholarly journals ECONOMIC APPROACH TO THE CHOICE OF TARGET WOOD SPECIES FOR THE FOREST GROWING IN KAMA REGION OF THE REPUBLIC OF TATARSTAN

2017 ◽  
pp. 20-27
Author(s):  
Пуряев ◽  
Aynur Puryaev ◽  
Мифтахов ◽  
Timur Miftakhov ◽  
Демаков ◽  
...  
Keyword(s):  
Tree Species ◽  
Market Value ◽  
Economic Assessment ◽  
Oak Forests ◽  
Forest Site ◽  
Economic Approach ◽  
Annual Increment ◽  
The Republic ◽  
Standard Terms ◽  
Mean Annual Increment

The objectives of economic assessment of forests, growing on rich soil and environmental conditions, are especially important for the Republic of Tatarstan, as forest site conditions are presented, mostly, fresh suramens and sudubravas. The aim is to develop an algorithm and a mathematical model of the tax and market value dynamics of stands, needed to justify the choice of target tree species. The object of the study is served as detached electronic database of forestry and forest taxation indices of Kama region, general commodity tables and rate per unit volume of standing wood. The methodology of the study was consistent sort and organize raw data on the studied parameters, as well as the drawing up of mathematical models of the dynamics of the studied parameters. According to the research rezults the algorithm of selecting the target tree species was developed, providing the highest economic benefit in cultivation. The pine stands are most profitable to grow at fresh suramens and oak forests at fresh sudubravas. Age of stand’s economic maturity, which occurs at the climax moment of values of mean annual increment of its tax value, is much lower for most tree species, than the established standard terms of logging.

scholarly journals Response of spring wheat to NPK and S fertilization. The content and uptake of macronutrients and the value of ionic ratios

2018 ◽  
Vol 16 (1) ◽  
pp. 1059-1065 ◽  
Author(s):  
Hanna Klikocka ◽  
Marek Marks ◽  
Bożena Barczak ◽  
Bogdan Szostak ◽  
Anna Podleśna ◽  
...  
Keyword(s):  
Field Experiment ◽  
Grain Yield ◽  
Spring Wheat ◽  
Positive Response ◽  
Dry Mass ◽  
Mass Ratio ◽  
P Content ◽  
Mass Ratios ◽  
S Application ◽  
S Fertilizers

AbstractThe aim of the study was to evaluate the effect of nitrogen (N) and sulphur (S) fertilizers on the content and uptake of macronutrients by grain dry mass (DM) of spring wheat. A field experiment was conducted in southeastern Poland on Cambisols (WRB 2007), in conditions of low S content in the soil. The experiment included 2 factors: fertilization with N (0, 40, 80, 120 kg ha-1) and with S (0, 50 kg ha-1).The experiment showed a positive response of spring wheat to N and S fertilization. The highest grain yield was found after application of 80 kg N ha-1 and addition of 50 kg S ha-1 (5.43 t ha-1). The described combination resulted in beneficial content of phosphorus (P), potassium (K), magnesium (Mg), calcium (Ca) (P –4.267, K–4.533, Mg–1.567, Ca–0.433 g kg-1) and uptake of macroelements by grain dry mass (DM) (P–20.48, K–21.79, Mg–7.52, Ca–2.08 kg ha-1). A generally positive correlation was found between content and uptake of macronutrients with exception of P content. Fertilization with N caused significantly narrowed mass ratios of K+: Ca2+, K+: Mg2+ and mass and mole ratio of K+:(Ca2++Mg2+) and increased mass ratio of Ca:P. While S application narrowed significantly, mass ratios of K+:Ca2+ and K+: (Ca2+ + Mg2+) and increased mass ratio of Ca:P.

Classification of Eucalyptus plantation Site Index (SI) and Mean Annual Increment (MAI) prediction using DEM-based geomorphometric and climatic variables in Brazil

2020 ◽  
pp. 1-18
Author(s):  
Aliny Aparecida Dos Reis ◽  
Steven E. Franklin ◽  
Fausto Weimar Acerbi Júnior ◽  
Antonio Carlos Ferraz Filho ◽  
José Marcio de Mello
Keyword(s):  
Site Index ◽  
Climatic Variables ◽  
Annual Increment ◽  
Eucalyptus Plantation ◽  
Mean Annual Increment

scholarly journals Modeling of REE and Fe Extraction from a Concentrate from Araxá (Brazil)

Minerals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 451 ◽  
Author(s):  
Marisa Nascimento ◽  
Flávio Lemos ◽  
Rogério Guimarães ◽  
Clóvis Sousa ◽  
Paulo Soares
Keyword(s):  
Laboratory Experiments ◽  
Earth Element ◽  
Process Variable ◽  
Optimization Method ◽  
Chemical Processing ◽  
Important Process ◽  
Mass Ratio ◽  
Process Variables ◽  
Acid Processing ◽  
Roasting Temperature

The study aimed to employ a comprehensive methodology for the acid processing of a rare earth element (REE) concentrate obtained from the ore from Araxá (MG-Brazil). The most important process variables have been identified and their levels determined to maximize REE extraction (%RE) and minimize Fe extraction (%Fe). The thermodynamic analysis showed that the roasting temperature (TF) is crucial for the control of Fe solubilization in the aqueous leaching step of the acid processing. A statistic design of laboratory experiments and a process optimization method were applied to address the interaction among the process variables. Experimental results showed that a TF of about 700 °C can significantly reduce the Fe concentration in the aqueous leaching liquor. Mathematical models were proposed to predict the effect of process variable on REE and Fe extraction of the concentrate. A multi-objective technique was employed for optimization of chemical processing and the best conditions were reached for roasting temperature (TF) = 700 °C, acid to sample mass ratio (ACs) = 0.8 and leaching time (tL) = 20 min, which led to %RE = 96.91% and %Fe = 21.69%.

Sign in / Sign up

Export Citation Format

Share Document