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Gas Exchange Rates of Texas Persimmon (Diospyros texana) in Central Texas Woodlands
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作者 Matthew B. Grunstra Oscar W. Van Auken 《American Journal of Plant Sciences》 CAS 2024年第5期329-348,共20页
Diospyros texana (Texas persimmon) is a secondary species in most Juniperus ashei/Quercus fusiformis woodlands in central Texas. It has high density, but plants are mostly in the community understory. Light response c... Diospyros texana (Texas persimmon) is a secondary species in most Juniperus ashei/Quercus fusiformis woodlands in central Texas. It has high density, but plants are mostly in the community understory. Light response curves at ambient and elevated levels of CO<sub>2</sub> and temperature were measured for D. texana. The A<sub>net</sub> (photosynthetic rate) increased significantly as both light level and CO<sub>2</sub> levels increased but not temperature. The A<sub>max</sub> (maximum photosynthetic rate) of D. texana in full sun at elevated levels of CO<sub>2</sub> was increased for all treatments. Stomatal conductance increased with levels of CO<sub>2</sub> but only if the interaction was removed from the model. Intercellular levels of CO<sub>2</sub> increased with both temperature and CO<sub>2</sub> treatments as did water use efficiency (WUE). Furthermore, light saturation (L<sub>sat</sub>) increased with CO<sub>2</sub> treatments and light compensation (L<sub>cp</sub>) increased with temperature. The dark respiration (R<sub>d</sub>) increased with both temperature and CO<sub>2</sub> treatments. Markov population models suggested D. texana populations would remain ecologically similar in the future. However, sub-canopy light levels and herbivory should be considered when examining population projections. For example, Juniperus ashei juveniles are not recruited into any canopy unless there are high light levels. Herbivory reduces the success of Quercus juveniles from reaching the canopy. These factors do not seem to be a problem for D. texana juveniles which would allow them to reach the canopy without need of a high light gap and are not prevented by herbivory. Thus, Juniperus/Quercus woodlands will change in the future to woodlands with D. texana a more common species. 展开更多
关键词 Replacement Dynamics Ecological Succession CO2 Concentrations Temperature Levels Photosynthetic rates Drought Tolerance HERBIVORY species Replacement ENCROACHMENT Juniper
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Classification of Principal Wood Species in China Based on the Physiomechanical Properties
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作者 Jianyi Zhu Hui Peng +2 位作者 Xiaoning Lu Jianxiong Lyu Tianyi Zhan 《Journal of Renewable Materials》 SCIE EI 2023年第3期1425-1437,共13页
Many tree species are planted in China with variable properties and usage.Toward exploring the structure-properties relationships of wood and classifying the species more reasonably,the physiomechanical properties of ... Many tree species are planted in China with variable properties and usage.Toward exploring the structure-properties relationships of wood and classifying the species more reasonably,the physiomechanical properties of the domestic wood species in China were analyzed statistically.According to the correlation analysis,the mechanical properties were closely related to the wood density.Except impact toughness and cleavage strength,the correlation coefficients between mechanical properties and densities were more than 0.8.However,shrinkage properties showed fewer correlations with densities,and the coefficient was no more than 0.7.Primary component analysis was proved to be feasible to explore the information of the physiomechanical properties.Two principal components(PC1 and PC2)could account for most of the information.PC1 and PC2 were designated as density-dominated and shrinkage-associated factors,respectively.The domestic wood species in China could be classified into 4 clusters based on their physiomechanical properties.According to the cluster results,reasonable grading was proposed for air-dried density,volume shrinkage,modulus of rupture,compression strength parallel to grain and hardness in cross section.The statistical results brought insights into analyzing the physiomechanical properties of domestic Chinese wood species,which was helpful for developing strategies of tree breeding and technologies of wood processing. 展开更多
关键词 Chinese wood species physiomechanical properties primary component analysis cluster analysis GRADING
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Survival of Seedlings of Native Woody Species in the Rehabilitation of Gold Mined-Site within a Three Years Old Acacia mangium Willd Plantation of St. Elizabeth-Mahdia, Guyana
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作者 Susy Lewis Lawrence Lewis Ryan Dey 《Journal of Environmental Science and Engineering(B)》 2023年第3期133-145,共13页
Active restoration is a critical component of biodiversity conservation for degraded tropical forest ecosystems caused by artisanal gold mining, and the success of restoration is dependent on native species selection.... Active restoration is a critical component of biodiversity conservation for degraded tropical forest ecosystems caused by artisanal gold mining, and the success of restoration is dependent on native species selection. However, significant knowledge gaps exist regarding when and where to plant trees. This article reports on a revegetation trial undertaken in St Elizabeth, Mahdia, Guyana, to assess the survival and RGR (Relative Growth Rate) of three native woody trees and shrubs planted within three years old Acacia mangium Willd trees pruned and unpruned blocks. ANOVA (Analysis of Variance) for a completely randomized block design with four blocks, two pruned and two unpruned, within A. mangium plots. Biochar treatment was added to the plants during transplanting. Thirty-six (36) wildlings of Humiria balsamifera (Aublet.) (Tauroniro), Goupia glabra Aublet (Kabukalli), and Vismia guianensis (Aublet.) Choisy (Bloodwood) were collected and raised in a tree nursery for two weeks. The native plants were transplanted 3 m apart, survival observations and each seedling’s initial height and diameter were measured and recorded. After the experiment, 13% of seedlings from a population of 720 had died, with the highest mortality being experienced at the 92 days of the experiment (t ≤ 122 days). While the overall survival rates were high, emphasizing the importance of field trials on native and exotic species in different environments is essential to fill the knowledge gaps on suitable species for restoration in degraded areas with other land use histories. 展开更多
关键词 Artisanal gold mining native species survival Acacia mangium diameter growth rate.
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Matrix Assisted Laser Desorption Ionization Time of Flight(MALDI-TOF)-Mass Spectrometry and^(13)C-NMR-Identified New Compounds in Paraberlinia bifoliolata(Ekop-Beli)Bark Tannins
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作者 Liliane Nga Benoit Ndiwe +3 位作者 Achille Bernard Biwolé Antonio Pizzi Jean Jalin Eyinga Biwole Joseph Zobo Mfomo 《Journal of Renewable Materials》 EI CAS 2024年第3期553-568,共16页
Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial sector.The discovery of new tannins is therefore necessary.The aim of this w... Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial sector.The discovery of new tannins is therefore necessary.The aim of this work was to contribute to the understanding of the properties of Paraberlinia bifoliolata tannin by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy MALDI-TOF/MS and Carbon 13 Nuclear Magnetic Resonance(13C NMR).The chemical composition of tannin extracted from Paraberlinia bifoliolata bark was determined,as was the mechanical strength of the resin hardened with Acacia nilotica extracts.Yield by successive water extraction was 35%.MALDI-TOF/MS analysis revealed the presence of three new compounds in this tannin,previously unknown in this family of extracts.These are 3-hydroxyproline acid,N-methyl-4-hydroxypipecolic acid and N-methyl-5-dihydroxypipecolic acid.The identification of the above molecules means that this tannin can be used for industrial applications,as a resin in the manufacture of particleboard and in the formulation of green corrosion inhibitors.This information is reinforced by 13C NMR spectrometry,which indicates the presence of several polyflavonoid units,confirming the condensed nature of the tannin.Thermomechanical analysis of the resin formed by the purified tannin of Paraberlinia bifoliolata to which a vegetal biohardener has been added provided a Modulus of Elasticity(MOE)value of 4840 MPa at 150℃,confirming its possible use as a binder resin in the manufacture of wood panels as well as for the formulation of a corrosion inhibitor. 展开更多
关键词 TANNIN Paraberlinia bifoliolata Central African wood species MALDI-Tof/MS 13C NMR bark extracts thermomechanical behaviour wood-binder
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Simulation of Steel Reinforcement on the Nonlinear Behaviour of Slender Glulam Beam Columns by Using the Newton-Raphson Method
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作者 Martial Ourmama Marcelline Blanche Manjia Edmond Dawak Fezeu 《Open Journal of Applied Sciences》 2024年第2期243-266,共24页
The current theory in NF EN 1995-1-1/NA of Eurocode 5, which is based on maximum deflection, has been investigated on softwoods. Therefore, this theory is not adapted for slender glulam beam columns made of tropical h... The current theory in NF EN 1995-1-1/NA of Eurocode 5, which is based on maximum deflection, has been investigated on softwoods. Therefore, this theory is not adapted for slender glulam beam columns made of tropical hardwood species from the Congo Basin. This maximum deflection is caused by a set of loads applied to the structure. However, Eurocode 5 doesn’t provide how to predict this deflection in case of long-term load for such structures. This can be done by studying load-displacement (P-Δ) behaviour of these structures while taking into account second order effects. To reach this goal, a nonlinear analysis has been performed on a three-dimensional beam column embedded on both ends. Since conducting experimental investigations on large span structural products is time-consuming and expensive especially in developing countries, a numerical model has been implemented using the Newton-Raphson method to predict load-displacement (P-Δ) curve on a slender glulam beam column made of tropical hardwood species. On one hand, the beam has been analyzed without wood connection. On the other hand, the beam has been analyzed with a bolted wood connection and a slotted-in steel plate. The load cases considered include self-weight and a uniformly applied long-term load. Combinations of serviceability limit states (SLS) and ultimate limit states (ULS) have also been considered, among other factors. A finite-element software RFEM 5 has been used to implement the model. The results showed that the use of steel can reduce displacement by 20.96%. Additionally, compared to the maximum deflection provided by Eurocode 5 for softwoods, hardwoods can exhibit an increasing rate of 85.63%. By harnessing the plastic resistance of steel, the bending resistance of wood can be increased by 32.94%. 展开更多
关键词 Nonlinear Analysis Newton-Raphson Method Maximum Deflection Bolted wood Connection Hardwood species
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Determination of the Properties of Some Selected Timber Species for Structural Application
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作者 Asimiyu Amobi Oyediran Catherine Mayowa Ikumapayi Babatola Olufemi 《World Journal of Engineering and Technology》 2023年第2期319-334,共16页
One of the alternative sustainable and green construction materials to concrete is timber. Timber is of numerous varieties, and this acts as a barrier to the extent of its usage, especially in structural application. ... One of the alternative sustainable and green construction materials to concrete is timber. Timber is of numerous varieties, and this acts as a barrier to the extent of its usage, especially in structural application. Despite many researches on wood’s mechanical and physical properties, only a few are geared toward the structural application of wood. The present work investigated the mechanical properties of five timber species;Gmelina arborea, Tectona grandis (Teak), Terminalia superba (Afara), Ayin (Anogeissus leiocarpus), and Acacia (Robinia pseudoacacia), to determine their suitability for constructing long-span roof trusses. These are available in the South Western part of Nigeria. Their mechanical properties;bending strength, compressive strength, shear strength, tensile strength, Modulus of Elasticity (MOE), Modulus of Rupture (MOR), and density, were determined in the laboratory. The results obtained showed that all the timber types, except Terminalia superba (Afara), have higher values of mechanical properties than the values that are obtainable for classes of strength D30 to class D70 in the British Code of Practice. It means these species are of higher quality than the stipulated strength classes in the British code. The results also show that the order of relevance of the species for structural design (or work) is Acacia (Robinia pseudoacacia), Ayin (Anogeissus leiocarpus), Gmelina Arborea, and Tectona grandis (Teak). Terminalia superba (Afara) is not recommended for structural works. 展开更多
关键词 Timber wood species Bending Strength Compression Mechanical Properties
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Embryonic Development and Eclosion Season of New Species Berastagia (Lepidoptera: Pyralidae) from Taiwan
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作者 Tzu-Yang Weng Wei Liang +3 位作者 Cian-Yi Lin Cha-Hao Hsu Ching-Jung Lin Yih-Tsong Ueng 《Natural Resources》 CAS 2023年第2期13-25,共13页
This paper describes a new species of the snout moth Berastagia tainanica sp. nov. (Lepidoptera: Pyralidae) from Taiwan. From 2009 to 2016, a biology study was conducted on population dynamics and embryonic developmen... This paper describes a new species of the snout moth Berastagia tainanica sp. nov. (Lepidoptera: Pyralidae) from Taiwan. From 2009 to 2016, a biology study was conducted on population dynamics and embryonic development. Spring season is the peak of the eclosion of overwintering larvae or pupae. The average longevity of adult was 14.8 ± 6.2 days (N = 174), the average number of eggs laid was 259 ± 3 eggs/moth (N = 2), the hatching rate of eggs was 95.4% (N = 262), and the average hatching time of eggs was 99.6 ± 18.6 hours (N = 68). The average body length of males was 5.64 mm ± 0.91 mm (N = 30), and the average body length of females was 6.28 mm ± 0.84 mm (N = 30). This finding indicates that female snout moths are larger than males (Global R = 0.058, P = 0.012). The snout moth eclosion rate was 16.9 moths/100 pods in the first year (2010/2011, N = 2,224 pods) and 10.9 moths/100 pods in the second year (2014/2015, N = 6,382 pods). The pod borer rate was 31.8% (N = 707) and the seed borer rate was 41.2% (N = 3,628) in the first year, whereas the pod borer rate was 76.2% (N = 6,382) in the second year. 展开更多
关键词 PHYCITINAE New species Embryonic Development Eclosion Season Borer Damage rate TAIWAN
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Decomposition dynamics of coarse woody debris of three important central European tree species 被引量:8
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作者 Steffen Herrmann Tiemo Kahl Jürgen Bauhus 《Forest Ecosystems》 SCIE CSCD 2015年第4期339-352,共14页
Background: Coarse woody debris (CWD) is an important element of forest structure that needs to be considered when managing forests for biodiversity, carbon storage or bioenergy. To manage it effectively dynamics o... Background: Coarse woody debris (CWD) is an important element of forest structure that needs to be considered when managing forests for biodiversity, carbon storage or bioenergy. To manage it effectively dynamics of CWD decomposition should be known. Methods: Using a chronosequence approach, we assessed the decomposition rates of downed CWD of Fagus sylvatica, Picea obies and Pinus sylvestfis, which was sampled from three different years of tree fall and three different initial diameter classes (〉10 - ≤20 cm, 〉20 - ≤40 cm, 〉40 cm). Samples originating from wind throws in 1999 were collected along a temperature and precipitation gradient. Based on the decay class and associated wood densities, log volumes were converted into CWD mass and C content. Log fragmentation was assessed over one year for log segments of intermediate diameters (〉20 - 40 cm) after 8 and 18 years of decomposition. Results: Significantly higher decomposition constants (k) were found in logs of F. sylvotica (0.054 year^-1) than in P. abies (0.033 year^-1) and P. sylvestris (0.032 year^-1). However, mass loss of P. sylvestris occurred mainly in sapwood and hence k for the whole wood may be overestimated. Decomposition rates generally decreased with increasing log diameter class except for smaller dimensions in P. obies. About 74 % of the variation in mass remaining could be explained by decomposition time (27 %), tree species (11%), diameter (17 %), the interactive effects between tree species and diameter (4 %) as well as between decomposition time and tree species (3 %) and a random factor (site and tree; 9.5 %), whereas temperature explained only 2 %. Wood fragmentation may play a more important role than previously thought. Here, between 14 % and 30 % of the decomposition rates (for the first 18 years) were attributable to this process. Carbon (C) density (mgC· cm ^-3), which was initially highest for F. sylvatico, followed by P. sylvestris and P. obies, decreased with increasing decay stage to similar values for all species. Conclusions: The apparent lack of climate effects on decomposition of logs in the field indicates that regional decomposition models for CWD may be developed on the basis of information on decomposition time, tree species and dimension only. These can then be used to predict C dynamics in CWD as input for C accounting models and for habitat management. 展开更多
关键词 Dead wood CARBON Decay rate BEECH SPRUCE PINE
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THE EFFECT OF HEAT TREATMENT ON DIFFERENT SPECIES WOOD COLOUR 被引量:3
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作者 刘一星 李坚 +2 位作者 王金满 严劲松 马彦华 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第4期73-78,共6页
In this paper, the heat tratment of wood samples of 8 tree species with different colour were made at different temperature and time. Using SC-1 Model colorimeter, the colorimetric parameter was measured at quantitati... In this paper, the heat tratment of wood samples of 8 tree species with different colour were made at different temperature and time. Using SC-1 Model colorimeter, the colorimetric parameter was measured at quantitative measuring for treatment fore-and-after wood sampIes color. The effect of heat treatment conditions on wood color was analyzed. The results indicated: the temperature and time of heat treatment affected on big extent for wood samples color, in which the heat temperature was more evident than others. The luminance index of wood color parameter was more sensitive to treatment condition, which it reduced with temperature and time increasing, this kind of variation tendency was the same as all wood samples, but the variations extent was more different among the different wood species. After heat treatment the wood color hue and saturation variation direction were different for different wood species.This phenomenon had the relation to the migration and volatilization of color extract in heating process, or the rapid oxidation of lignin and some chemical element in high temperature. 展开更多
关键词 wood COLOR Heat treatment TREE species Temperature
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A feasibility study of using two-component polyurethane adhesive in constructing wooden structures 被引量:1
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作者 Mohammad Derikvand Ghanbar Ebrahimi Mehdi Tajvidi 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第2期477-482,共6页
This investigation was conducted to determine the feasibility of using a two-component polyurethane (PUR) adhesive, with special waterproof properties, in constructing wooden structures. We designed and conducted te... This investigation was conducted to determine the feasibility of using a two-component polyurethane (PUR) adhesive, with special waterproof properties, in constructing wooden structures. We designed and conducted tests to compare the shear strength and adhesion performance of PUR with polyvinyl acetate (PVAc) adhesive on block-shear specimens constructed of oriental beech (Fagus orientalis L.), fir (Abies alba Mill.), poplar (Populus deltoides Bartr.), white oak (Quercus alba L.), sycamore (Platanus orientalis L.) and white walnut (Juglans cinerea L.). The values of the percentage of wood failure were also determined in specimens constructed with each adhesive. The highest shear strength values of both adhesives were obtained in specimens constructed of beech, while the lowest shear strength values were obtained in fir and poplar specimens. Average shear strength of the PUR adhesive was 16.5% higher than that of the PVAc adhesive. Specimens constructed of fir, poplar and sycamore were characterised by the highest percentages of wood failure, whereas the lowest average percentages of wood failure were obtained in beech and oak specimens. With the exception of oak specimens, there was no statistically significant difference between percentage of wood failure among the PUR and PVAc adhesives. Generally, the PUR adhesive showed an acceptable adhesion performance on wood materials used in our study. 展开更多
关键词 wooden structures polyurethane adhesive polyvinyl acetate adhesive shear strength wood failure wood species
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Effects of wood species and retention levels on removal of copper,chromium,and arsenic from CCA-treated wood using sodium hypochlorite 被引量:1
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作者 Engin Derya Gezer Paul A.Cooper 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第2期433-442,共10页
Chemical extraction, bioremediation, and electrodialytic processes have been extensively studied for removal of copper, chromium, and arsenic from wood treated with chromated copper arsenate (CCA). However, one prob... Chemical extraction, bioremediation, and electrodialytic processes have been extensively studied for removal of copper, chromium, and arsenic from wood treated with chromated copper arsenate (CCA). However, one problem has not been addressed: the effects of wood species and retention levels on remediation efficiency. The objectives of this study were to investigate the effects of wood species and retention levels on removal of copper, chromium, and arsenic from CCA-treated wood samples using sodium hypochlorite. Our results showed that sodium hypochlorite (NaOC1) was very effective for removal of copper, chromium, and arsenic from CCA-C treated milled wood samples for all three species used in this study. The Cu, Cr, and As extraction efficiencies for red pine were 95 % Cu, 97 % Cr and 94 % As, for maple were 95 % Cu, 97 % Cr, and 98 % As at 4.0 kg m-3 retention levels, and for aspen were 95 % Cu, 92% Cr, and 91% As at 9.6 kg m-3 retention level, respectively. However, the results showed that wood species and initial retention levels of CCA-treated wood products played very impor- tant roles in terms of removal of Cu, Cr, and As. 展开更多
关键词 Chromated copper arsenate (CCA) REMEDIATION Remediation efficiency wood species Retention level
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Qualitative and Quantitative Characterization of Wood Fibers of Shrubs and Tree Species of the Tamaulipan Thorn Scrub, Northeastern Mexico and Its Possible Relation to Wood Quality and Utilization 被引量:1
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作者 Ratikanta Maiti Humberto G. Rodriguez Aruna Kumari 《American Journal of Plant Sciences》 2016年第7期1046-1057,共12页
The present study was undertaken to determine the variability in fiber cell morphology and its length among wood species of the Tamaulipan Thorn Scrub, Northeastern Mexico, used for various uses such as timber for fur... The present study was undertaken to determine the variability in fiber cell morphology and its length among wood species of the Tamaulipan Thorn Scrub, Northeastern Mexico, used for various uses such as timber for furniture, fence, post, firewood and sources of forage. The results reveal large variability in fiber cell morphology and fiber cell dimensions. The species are classified on the basis of its fiber cell morphology and fiber cell length and recommended for their possible utilization for different purposes. Wood having fibre cells with broad lumen and thin wall could be suitable for the manufacture of paper documented in the literature viz. Acacia farnesciana, Caesalpinia mexicana, Cordia boisiieri, Diospyros palmeri, Forestieria angustifolia, Morus celtifolia, Prosopis laevigata. This technique can be used in preliminary screening of woody species for its utilization for different purposes. Further studies are needed to confirm. 展开更多
关键词 wood Fiber Cells Characterization VARIABILITY woody species wood Quality Tamualipan Thorn Scrub
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Development of a Seaweed Species-Selection Index for Successful Culture in a Seaweed-Based Integrated Aquaculture System 被引量:3
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作者 Yun Hee Kang Jae Ran Hwang +1 位作者 Ik Kyo Chung Sang Rul Park 《Journal of Ocean University of China》 SCIE CAS 2013年第1期125-133,共9页
Integrated multi-trophic aquaculture (IMTA) has been proposed as a concept that combines the cultivation of fed aquaculture species (e.g., finfish/shrimp) with extractive aquaculture species (e.g., shellfish/seaweed).... Integrated multi-trophic aquaculture (IMTA) has been proposed as a concept that combines the cultivation of fed aquaculture species (e.g., finfish/shrimp) with extractive aquaculture species (e.g., shellfish/seaweed). In seaweed-based integrated aquaculture, seaweeds have the capacity to reduce the environmental impact of nitrogen-rich effluents on coastal ecosystems. Thus, selection of optimal species for such aquaculture is of great importance. The present study aimed to develop a seaweed species-selection index for selecting suitable species in seaweed-based integrated aquaculture system. The index was synthesized using available literature-based information, reference data, and physiological seaweed experiments to identify and prioritize the desired species. Undaria pinnatifida, Porphyra yezoensis and Ulva compressa scored the highest according to a seaweed-based integrated aquaculture suitability index (SASI). Seaweed species with the highest scores were adjudged to fit the integrated aquaculture systems. Despite the application of this model limited by local aquaculture environment, it is considered to be a useful tool for selecting seaweed species in IMTA. 展开更多
关键词 水产养殖系统 物种选择 海藻 指数系统 文化选择 养殖发展 水产养殖环境 养殖品种
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THE EFFECT OF WOOD SURFACE ROUGHNESS OF DIFFERENT SPECIES OF TREES ON WOOD COLOR IN WORKING OPERATION
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作者 刘一星 王金满 +1 位作者 李坚 赵学增 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第1期66-70,共5页
The multinomial wood surface roughness parameters and wood color parameters of 5 kinds of species of trees were measured in working operation by the stylus surface roughness meter and colorimeter, and the measurement ... The multinomial wood surface roughness parameters and wood color parameters of 5 kinds of species of trees were measured in working operation by the stylus surface roughness meter and colorimeter, and the measurement results were compared. The results indicated: The variations of wood surface roughness had the effect on the wood color of some kinds of species of trees on working operation, with the surface roughness decreasing, the brightness and luminance exponent increased, the hue angle increased lightly, but the variation of color saturation was different to the different wood color hue of species of trees. 展开更多
关键词 wood color Surface roughness Tree species wood working operation
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Biomolecules of Interest Present in the Main Industrial Wood Species Used in Indonesia-A Review
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作者 Resa Martha Mahdi Mubarok +4 位作者 Wayan Darmawan Wasrin Syafii Stéphane Dumarcay Christine Gérardin Charbonnier Philippe Gérardin 《Journal of Renewable Materials》 SCIE EI 2021年第3期399-449,共51页
As a tropical archipelagic country,Indonesia’s forests possess high biodiversity,including its wide variety of wood species.Valorisation of biomolecules released from woody plant extracts has been gaining attractive ... As a tropical archipelagic country,Indonesia’s forests possess high biodiversity,including its wide variety of wood species.Valorisation of biomolecules released from woody plant extracts has been gaining attractive interests since in the middle of 20th century.This paper focuses on a literature review of the potential valorisation of biomolecules released from twenty wood species exploited in Indonesia.It has revealed that depending on the natural origin of the wood species studied and harmonized with the ethnobotanical and ethnomedicinal knowledge,the extractives derived from the woody plants have given valuable heritages in the fields of medicines and pharmacology.The families of the bioactive compounds found in the extracts mainly consisted of flavonoids,stilbenes,stilbenoids,lignans,tannins,simple phenols,terpenes,terpenoids,alkaloids,quinones,and saponins.In addition,biological or pharmacological activities of the extracts/isolated phytochemicals were recorded to have antioxidant,antimicrobial,antifungal,anti-inflammatory,anti-diabetes,anti-dysentery,anticancer,analgesic,anti-malaria,and anti-Alzheimer activities.Aside from these remarkable characteristics of woody plant extractives,further studies concerning the valorisation of these extractives in the fields of nutraceutical,cosmetic,bio-control,bio-stimulation,and other advanced applications would be of interest. 展开更多
关键词 BARK BY-PRODUCT bioactivity extractive Indonesia industry MOLECULE VALORIZATION wood species
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Growth Characteristics, Biomass and Chlorophyll Fluorescence Variation of Garhwal Himalaya’s Fodder and Fuel Wood Tree Species at the Nursery Stage
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作者 Azamal Husen 《Open Journal of Forestry》 2013年第1期12-16,共5页
Fodder and fuel wood deficiency in the Himalayan region is well recognized. Rural inhabitants are exploiting these forest resources for their livelihood for generations which leads to severe deforestation. The aim of ... Fodder and fuel wood deficiency in the Himalayan region is well recognized. Rural inhabitants are exploiting these forest resources for their livelihood for generations which leads to severe deforestation. The aim of this study was to identify the fast growing fodder and fuel wood tree species of Garhwal Himalayas at nursery stage with wider relevance and great potential for extensive afforestation programmes. Seed of Bauhinia purpurea L., Bauhinia retusa Roxb., Bauhinia variegate L., Celtis australis L., Ficus nemoralis Wall., Ficus roxburghii Wall., Grewia optiva Drummond, Leucaena leucocephala (Lam.) de Wit, Melia azedarach L., Ougeinia oojeinensis (Roxb.) Hochr., Quercus leucotrichophora A. Camus, Terminalia alata Heyne ex Roth. and Toona ciliate M. Roem. were collected from the superior trees and seedlings were raised. After one year and one month of establishment at the nursery, the growth characteristics, biomass and chlorophyll fluorescence (dark-adopted Fv/Fm) of each species were also recorded. G. optiva had shown the highest growth in terms of height, basal diameter increment and number of branches, while production of leaves was more on O. oojeinensis. Biomass and chlorophyll fluorescence (maximum quantum yield or photochemical efficiency of PSII) was found highest in Q. leucotrichophora which indicates photosynthetically this species was most active among the studied fodder and fuel wood tree species. The information in this communication could be utilized for developing various conservation and sustainable strategies in the Garhwal Himalayas to mitigate 展开更多
关键词 SCARCITY FODDER and Fuel wood species Screening Growth BIOMASS CHLOROPHYLL
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Effect of Tree Species and Dosage of Rhizomorph Wood on Asexual Propagation of Wild Gastrodia elata. Bl. f. glauca S. Chow in Ganzi
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作者 Xueqiang XIE 《Agricultural Science & Technology》 CAS 2015年第9期1840-1844,共5页
The effects of the tree species and the dosages of Armillariella mellea rhizomoph wood on asexual propagation of wild Gastrodia elata Bl. f. glauca S. Chow were studied in Ganzi prefecture. The results showed that tre... The effects of the tree species and the dosages of Armillariella mellea rhizomoph wood on asexual propagation of wild Gastrodia elata Bl. f. glauca S. Chow were studied in Ganzi prefecture. The results showed that tree species had a very significant effect on asexual reproduction yield of wild Gastrodia elata Bl. f. glauca S. Chow. The drying rate and yield of Gastrodia elata Bl. f. glauca S. Chow cultured by close grained woods such as Quercus spinosa David ex Fr. was extremely significant higher than that cultured by coarse grained wood such as Betula platyphylla Suk. The dosage had a very significant effect on the yield of wild Gastrodia elata Bl. f. glauca S. Chow whereas it had no influence on the drying rate. 展开更多
关键词 野生天麻 无性繁殖 青冈 剂量效应 树种 饲料产量 干燥速率 甘孜州
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Effects of Phosphoric Acid on Liquefaction of Wood in Phenol and Optimum Liquefaction Processing Parameters 被引量:17
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作者 ZhangQiuhui ZhaoGuangjie JieShujun 《Forestry Studies in China》 CAS 2004年第3期50-54,共5页
关键词 wood liquefaction PHENOL residue rate liquefaction processing parameters
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Impact of exclosures on wood biomass production and fuelwood supply in northern Ethiopia 被引量:2
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作者 Wolde Mekuria Mastewal Yami +2 位作者 Mitiku Haile Kindeya Gebrehiwot Emiru Birhane 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第2期629-637,共9页
In the Ethiopian highlands, communal grazing lands are one of the major land uses, and are source of livelihood for the rural people. Free and uncontrolled grazing in the communal grazing lands is the dominant grazing... In the Ethiopian highlands, communal grazing lands are one of the major land uses, and are source of livelihood for the rural people. Free and uncontrolled grazing in the communal grazing lands is the dominant grazing system. The traditional uncontrolled and free grazing system has caused severe degradation of the grazing lands. As a result, communities have started to establish exclosures and support the restoration of degraded communal grazing lands. Studies have shown that exclosures are effective to restoring degraded communal grazing lands and improving ecosystem services. However, studies that investigate the changes in aboveground biomass following the establishment of exclosures and compare it with fuelwood demand of the beneficiaries in our study area is lacking. Therefore, our study aimed at:(1) quantifying yearly biomass accumulation in exclosures and compare it to fuelwood demand of households that manage the exclosures;(2) assessing household energy sources and their consumption levels. To monitor changes in biomass production with over time, replicated(n = 3) 5 and10 year-old exclosures were sampled. To investigate fuelwood sources and consumption patterns, household surveys, key informant interviews and focus group discussion were conducted. Our results demonstrated that total biomass production increased with exclosure age. In both exclosure, biomass production from Vachellia etbaica was significantly(p \ 0.05) greater than that from Euclea.racemosa. Average daily fuelwood consumption per person was(0.63 ± 0.2) kg day^(-1). This means that the total biomass(27.5 Mg year^(-1)) obtained from 114.6 ha of exclosures covers only 9.4% of yearly fuelwood demand of the residents who manage the sampled exclosures. Nearly all respondents(95%) confirmed that they travel more than10 km day^(-1) to gather fuelwood from surrounding degraded forest patches. We recommend plantings of fast growing native tree species within exclosures and around homesteads to provide a sustainable fuelwood supply and using improved stoves to address the problem of fuelwood shortage. District agricultural offices could provide seedlings of native plant species, while communities provide unpaid labour for planting and managing plantations. 展开更多
关键词 BIOMASS Ethiopia EXCLOSURES FUEL wood Tigray woodY species
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Analysis of Energetic Species Caused by Contact Glow Discharge Electrolysis in Aqueous Solution 被引量:1
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作者 高锦章 王爱香 +5 位作者 付燕 吴建林 马东平 郭晓 李岩 杨武 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第1期30-38,共9页
Contact glow discharge electrolysis is a non-Faradaic electrochemical process with an abnormal relationship between the current and voltage. Hydroxyl radicals, hydrogen radicals and hydrogen peroxide can be produced u... Contact glow discharge electrolysis is a non-Faradaic electrochemical process with an abnormal relationship between the current and voltage. Hydroxyl radicals, hydrogen radicals and hydrogen peroxide can be produced under the glow discharge, which are often used to degrade organic contaminants in aqueous solution. In this study, with 4-nitrophenol taken as an example of contaminants and tert-butanol as a scavenger of hydroxyl radicals, the role of energetic species in degrading organic compounds was examined in detail. Moreover, the effects of the applied voltage, solution conductivity and pH on the formation of three energetic species were also observed. The formation rate constants of the three energetic species were calculated based on the experimental data. 展开更多
关键词 contact glow discharge electrolysis ANALYSIS energetic species formation rate constant
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