Bark Content Research Articles

Bark Content of Two Shrub Willow Cultivars Grown at Two Sites and Relationships with Centroid Bark Content and Stem Diameter

Understanding the characteristics of short rotation woody crops (SRWC), like shrub willow, that affect feedstock quality and its variability is a priority as this source of biomass is expanded. Because of its relationship to ash content, the allotment of bark and wood within the stem is often highlighted as a factor impacting feedstock quality. Bark-to-wood ratios are frequently determined in willow by measuring this ratio for the centroid and assuming it represents the entire stem. The objectives of this study were to determine how site and genetic factors influenced the allometry of whole stem bark (WSB%) content on a dry weight basis and if the centroid bark percentage (CB%) on a dry weight basis adequately represents WSB%. A multiple linear regression approach was used to model WSB% and centroid bark content (CB%) using diameter, cultivar, and site factors. Five candidate models were evaluated ranging from parsimonious to complex. The simplest models estimated WSB% from CB% (R 2 = 0.76) and stem diameter (R 2 = 0.44). The most complex model included all factors and had an R 2 of 0.90. Two key relationships demonstrated by several models are that (1) CB% adequately predicts but underestimates WSB%, particularly for larger stems, and (2) WSB% increases as diameter decreases. However, empirical models can be enhanced with the inclusion of diameter, site, and cultivar information. The overall approaches can be useful for making relative comparisons between cultivars and sites. In a 3-year-old stand of willow stems less than 20 mm had high WSB%, the maximum being 23.8 %, but accounted for only 5 to 15 % of the total biomass. Large diameter stems accounted for the majority of the total and bark biomass, but the WSB% in large diameter stems is as low as 11.5 %. WSB% ranged from 12.9 to 14 % across the two cultivars at the stand level.

Organic Growing Media: Constituents and Properties

Organic growing media are essentially bulk products. Availability in large quantity allied to its excellent air and water retention, low pH and salinity, and freedom from pests and diseases has led to peat being the dominant organic constituent of growing media in many parts of the world for the last 50 yr. The unique microporous properties of Sphagnum peat and its resistance to degradation are matched by few other growing media constituents. Nevertheless, local scarcity of Sphagnum peat and the expense of transport has led to the use of other materials in growing media. Notable among these is coir, which unlike peat, a CO2 sink, is widely regarded as a rapidly renewable resource. Indeed, advances in processing and quality control in situ have led to a huge upsurge in the export and use of coir in growing media, particularly in Europe but also in the western United States. Locally available organic materials such as bark, composted materials including green (yard) wastes, municipal solid wastes, and even sewage sludge are also used in growing media. While possessing advantages such as the high air content of bark and nutrient supply of many composted materials, these media components may have disadvantages, from limited supplies due to bioenergy pulls and N lock‐up in bark, to physical, chemical, and microbial contaminants in composts. Current innovative approaches involve increasing use of wood fiber in Europe, whole pine‐tree thinnings in the United States, and realizing the use and transformation of composted wastes as next‐generation constituents of growing media.

Bark ecology of twigs vs. main stems: functional traits across eighty-five species of angiosperms.

Although produced by meristems that are continuous along the stem length, marked differences in bark morphology and in microenvironment would suggest that main stem and twig bark might differ ecologically. Here, we examined: (1) how closely associated main stem and twig bark traits were, (2) how these associations varied across sites, and (3) used these associations to infer functional and ecological differences between twig and main stem bark. We measured density, water content, photosynthesis presence/absence, total, outer, inner, and relative thicknesses of main stem and twig bark from 85 species of angiosperms from six sites of contrasting precipitation, temperature, and fire regimes. Density and water content did not differ between main stems and twigs across species and sites. Species with thicker twig bark had disproportionately thicker main stem bark in most sites, but the slope and degree of association varied. Disproportionately thicker main stem bark for a given twig bark thickness in most fire-prone sites suggested stem protection near the ground. The savanna had the opposite trend, suggesting that selection also favors twig protection in these fire-prone habitats. A weak main stem-twig bark thickness association was observed in non fire-prone sites. The near-ubiquity of photosynthesis in twigs highlighted its likely ecological importance; variation in this activity was predicted by outer bark thickness in main stems. It seems that the ecology of twig bark can be generalized to main stem bark, but not for functions depending on the amount of bark, such as protection, storage, or photosynthesis.

Relative Bark Thickness is Correlated with Tree Species Distributions along a Fire Frequency Gradient

AbstractThe probability of stem survival after fire is strongly influenced by energy allocation to bark because bark thickness affects heat transfer during fire. Greater relative investment in inner bark versus outer bark should also enhance survival because of greater moisture content of inner bark. We measured stem diameter, bark thickness, and habitat preference of five species typical of long-leaf pine savannas, and six species characteristic of adjacent wetlands (pocosins), and calculated relative bark thickness, the inner bark proportion, radial growth, and bark accumulation of each species. We hypothesized that savanna species have thicker bark and greater relative investment in inner bark than pocosin species, because fires occur more frequently in savannas than pocosins. As hypothesized, savanna species have relatively thicker bark than pocosin species. Relative bark thickness and the rate of bark accumulation were correlated with the mean location of a species along the pocosin-to-savanna gradient. However, the inner bark proportion did not differ between savanna and pocosin species. Our results indicate that relative bark thickness is likely the primary bark trait affecting fire-induced topkill and influencing the distribution of species along the pocosin-to-savanna gradient.

추출조건에 따른 옻나무 부위별 Phenolics 함량

This study investigated changes in phenolic contents of different parts of Rhus verniciflua Stokes (RV) according to extraction conditions. Bark and xylem parts of RV were extracted at 80, 100, 120, 140, and 160°C for 1, 3, and 5 h, respectively. Major phenolic compounds (gallic acid, protocatechuic acid, fustin, fisetin, sulfuretin, and butein) of RV were analyzed. The gallic acid, fisetin, sulfuretin, and butein contents significantly increased as extraction temperature increased. Protocatechuic acid and fustin contents increased as increasing extraction temperature to 120°C and decreased afterward. The gallic acid, protocatechuic acid, and butein contents of bark were higher than those of xylem extracts. The optimal extraction conditions of gallic acid, protocatechuic acid, fustin, fisetin, sulfuretin, and butein were 160°C/3 h (380.22 mg%), 120°C/1 h (9.25 mg%), 100°C/3 h (206.97 mg%), 140°C/5 h (93.84 mg%), 140°C/5 h (16.07 mg%) and 160°C/5 h (1.49 mg%), respectively. These results suggest that the optimum extraction temperature and time considering RV extraction yield and cost are 140°C and 3 h, respectively.

Ligninolytic enzymes production by Dichostereum sordulentum cultures in the presence of Eucalyptus bark as a natural laccase stimulator

A strain of a fungal species, i.e., Dichostereum sordulentum, not yet isolated from either Uruguay or decayed Eucalyptus spp. wood, was investigated for its ability of producing extracellular ligninolytic enzymes. To this aim, the strain was grown on a N-rich liquid medium added with either bark or wood Eucalyptus dunnii sawdust. The former additive was more effective than the latter instimulating laccase leading to a production of 4.78 IU mL-1 which was further enhanced by the concomitant presence of 80 ppm CuSO4 (6.56 IU mL-1). The two order of magnitude higher proanthocyanidin content in bark than in wood suggests that this fraction might be responsible for the higher stimulatory effect of the former on laccase production.

The bark of Scots pine (Pinus sylvestis L.) as a biological indicator of atmospheric air pollution

In dead bark layer 0f Scots pines (<i>Pinus sylvestris</i> L.) exposed to the emission of aluminium works and the electric power plant "Skawina" as well as of chemical plants in Cracow, pH was determined and the content of F, S, Mg, Na, P, K, and Ca. The F content in the dead pine bark varied from 0.018 to 0.386 mg/g, and that of sulphur from 1.00 to 3.83 mg/g. A significant correlation was demonstrated between pH, and fluorine and calcium content in the bark. On the other hand, sulphur content was dependent on the amount of Na, K and Ca. For demonstrating contamination of the surface bark layer a test was applied consisting in evaluation of the germinating and development capacity of seeds. Fluorine content in pine dead bark layer reflects the F concentration in atmospheric air, it may, therefore, serve as indicator of the degree of air pollution with fluorine compounds.

Changes in log quality at different decay stages in an alpine forest

Aims Log is an important pool of carbon (C) and nutrients in alpine forest ecosystems. Changes in log quality with decay could reveal the process of C and nutrient release during log decomposition. However, little informa- tion is available on this. Therefore, this study aims to understand the changes in log quality during log decaying. Methods Changes in C, nitrogen (N), phosphorus (P), lignin and cellulose concentrations were investigated in the heartwood, sapwood and bark of fir (Abies faxoniana) logs at five (I-V) decay stages in an alpine forest in western Sichuan, China. The stoichiometry of C:N:P and the ratios of lignin:N, lignin:P, cellulose:N, and cellu- lose:P were also calculated. Important findings C content in bark increased from the stage I to stage III of decay and then significantly de- creased, but in the heartwood and sapwood it decreased from the stage I through stage V, especially at stages IV and V. N content increased from the stage I through stage V regardless of the log components. P content in sap- wood also showed tended to increase from the stage I through stage V, but P content in heartwood and bark de- creased following an increase tendency. In comparison with sapwood and heartwood, bark had the lowest C:N:P stoichiometry at the same decay stages. Percentage of the labile to total C (Fm) also inferred that bark was the most decomposable component. The higher C:N:P stoichiometry in sapwood was observed in logs of the stages I and II, but higher Fm in heartwood was detected from the stage III to stage V. Critical values of C:N in sapwood and bark and C:P in heartwood, sapwood and bark were negatively correlated with the initial N and P concentra- tions, respectively. Cellulose concentration decreased from the stage I to stage V regardless of log components,

Heartwood, sapwood and bark variation in coppiced <i>Eucalyptus globulus</i> trees in 2nd rotation and comparison with the single-stem 1st rotation

Coppiced trees with 18 years in a 2nd rotation were analysed in relation to heartwood, sapwood and bark content taking into account the effect of the initial planting density by using a spacing trial. A total of 25 stumps, with a variable number of stems per stump from 1 to 3, were analysed. Comparison was made to the previous 1st rotation single stem trees, also harvested at 18 years. In the 2nd rotation, the stump density did not significantly affect stem height and diameter, in opposition to the 1st rotation where spacing significantly impacted on tree dimensions. The effect of the initial planting density is somewhat lost in the coppiced stand in relation with i.e. the number of stems per stump. Heartwood was present in all the coppiced trees up to 49.9% of the total tree height and heartwood volume amounted to 38.9–51.7% of the total tree volume. Within the tree, heartwood content decreased from the base upwards, representing, on average, 54.1% at the base and decreasing to 5.1% at 15.3 m. The sapwood width remained relatively constant with an average radial width of approximately 2 cm. The average stem bark content of coppiced trees was 17.4% of the total stem volume. The comparison of heartwood and sapwood development in the coppiced trees did not show significant differences to the 1st rotation trees, nor did the initial spacing. Heartwood diameter could be modelled using the tree diameter both for 1st and 2nd rotation trees.Eucalyptus globulus

Antimicrobial Activities of the Extracts from Bark of Ironwood (Mesua ferrea) and their Role in Production of Traditional Sugar Palm Wine

Bark from ironwood (chuồn in Vietnamese) is used in the production of traditional sugar palm wine of ethnic minorities in Central Vietnam. The objectives of this study were to investigate the antimicrobial properties of water and alcohol extracts of this bark and to determine the major active chemical components in these extracts. The agar well diffusion test was used to evaluate the antimicrobial activities of water and ethanol (10% v/v and 30% v/v) extracts of ironwood bark against Escherichia coli, Staphylococcus aureus, Acetobacter xylinum and Saccharomyces cerevisiae. All the extracts were found to possess significant inhibitory property against the tested microorganisms except S. cerevisae. The higher antimicrobial properties were noticed in the ethanol extracts compared to that of the water extract. Such antimicrobial property of the bark could explain its important role in supporting spontaneous alcohol fermentation of sugar palm sap in traditional wine making by ethnic minorities in Central Vietnam. The study also revealed the presence of saponins, tannins, phenols, terpenoids and flavonoids in the bark extracts. The analysis of flavonoid content in the ironwood bark gave the result of 15.57% (on dry basis), these flavonoids were also found to possess stronger antimicrobial activities than those of the ethanol extracts.

Fuel Properties of Woody Pellets in Domestic Markets of Korea

This study investigated physical properties and combustion gas characteristics for 8 types of wood pellets (4 domestic and 4 imported products) distributed in the domestic market. Results showed that most pellet types were first-grade pellets in the wood pellet quality standards in Korea with the exception of 3 pellet types from K company (second-grade in mechanical durability), G company (off-grade in nitrogen content) and P company (second-grade in ash percentage). Mixed pellets which contained more lignin and sap content were higher in mechanical durability (%) than that of white pellets. From the combustion gas analysis results, NOx emitted from all pellets combustion was at acceptable levels for national emission standard of the Clean Air Conservation Act except for pellets from G company. In addition, CO levels from all types of wood pellets were acceptable except for pellets from D company and domestic pellets were higher CO levels than imported pellets. These results indicate the higher CO levels in domestic pellets due to the usage of forest thinning materials including logging debris which usually had the high content of bark.

Estimating aboveground woody biomass of forests in Poland for FAO/ECE and UNFCCC reporting

Abstract The United Nations Framework Convention on Climate Change and the Kyoto Protocol have committed member states to reduce greenhouse gas emissions by, among others, promoting the increase of carbon sequestration by carbon sinks (including woody biomass in forests). In order to achieve these objectives, an international reporting system was designed. The stock of woody biomass depends on several environmental and managerial factors, which determine species composition and age structure of a forest as well as characteristics of individual trees. Estimating aboveground woody biomass, especially on a nation-wide level, is generally based on the application of conversion factors to known characteristics such as the volume of the growing stock. The application of default conversion factors, as proposed by international guidelines, however, is questionable, since inventory systems for and definitions of growing stock differ from country to country. In this paper, the methods used in Poland to estimate woody biomass for the FAO and the UNFCC reporting, were presented and analysed. We also analysed the influence of some stand and tree characteristics, such as tree species composition and content of bark and its density, on the stock of woody biomass. We conclude that issues not addressed in the IPCC guidelines, such as big differences in wood and bark density, especially for pine, need to be taken into consideration when making estimations. Moreover, the results of this paper show that biomass conversion and expansion factors (BCEF) proposed by IPCC are not adequate for Polish conditions.

Evaluation of Free Radical Scavenging and Polyphenolic Contents of Bark of <i>Pterygota alata</i> Roxb

Pterygota alata is a large deciduous tree of Malvaceae family. The present study was designed to evaluate in vitro antioxidant activity of stem bark of the plant. Ferric reducing power (FRP) test, 1, 1- diphenyl-2-picryl hydrazyl (DPPH) free radical scavenging test and total antioxidant capacity (TAC) assay were used to detect the antioxidant activity. Total phenolic and flavonoid contents were also determined as they are well known phytochemicals with antioxidant property. The bark of the plant showed efficient reducing power as well as free radical scavenging property (IC50 values 52.25 - 172.05). The bark also found rich in total phenolic and flavonoid content. The highest amount of total phenolic content was found in chloroform soluble fraction (29.898 µg/mL) followed by ethyl acetate soluble fraction (15.88 µg/mL). The highest content of total flavonoid also detected in chloroform soluble fraction (107.56 µg/mL) but followed by crude ethanol extract (98.66 µg/mL). Overall, the bark of the plant possesses significant antioxidant activity, therefore can be used as a good natural source of antioxidant. © 2014 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. doi: http://dx.doi.org/10.3329/jsr.v6i3.17586 J. Sci. Res. 6 (3), 543-552 (2014)

Review of Health and Safety Risks of Wood Chips Use

Alternative solid fuels becoming popular thanks to considerable fuel cost save (comparing to gas). Pellet quality varies depending on content of bark, straw and other non-wood additives. These additives decrease the combustion efficiency and increase the fuel consumption and solid emission. Pellets stored in large amount bring certain hazard for a man. They may become dangerous for the high fire risk due to self-ignition tendency and also due to moulds presence attacking the human breath system.

The effect of bark on sulfur dioxide–ethanol–water fractionation and enzymatic hydrolysis of forest biomass

The focus of this study was to find out the effect of bark on SO2–ethanol–water (SEW) fractionation and enzymatic hydrolysis of forest biomass. Softwood bark was found to be more harmful than hardwood bark in both processes. For softwood, the amount of undigested wood in SEW fractionation increased with the increasing bark content, whereas the hardwood bark did not impair the fractionation of wood. The higher the softwood bark content was the lower were the yields in enzymatic hydrolysis likely due to the unproductive binding of enzymes on lignin and other compounds. Addition of surfactant Tween 20 (2% w/w on substrate) prior to enzyme more than doubled the sugar yield of bark-rich softwood pulp. Hardwood bark impaired enzymatic hydrolysis when its share was over 28%. According to a preliminary study, lignosulfonates from the carry-over liquor seem to improve the sugar yield in the enzymatic hydrolysis by acting as a surfactant.

Нормативы по таксации древесной коры в стволах и сортиментах из берез

Percentage of bark in trunks and roundwood is investigated produced from birch (Betula verrucosa) in conditions of the Leningrad region. Background information for the study were the data on the inventory of model trees made at the trial plots laid down in parts of the region with a share of birch more than 30 %. Volumes of trunks and volumes of individual assortments in the bark and without bark were calculated from the sum of the volumes of sections. Bark content was determined as a percentage from volume with bark for trunks and without bark - for assortments.

The evolution of bark mechanics and storage across habitats in a clade of tropical trees.

• Bark functional strategies vary conspicuously within communities. As a result, predicting most community-level bark traits based on environment often reveals little association. To complement this community-based view, we took a clade-based approach to study potentially adaptive differences in bark water storage and biomechanics across habitats and examined ontogenetic mechanisms that lead to these differences.• We studied the branches of nine species in the simaruba clade of Bursera in dry to wet, fire-free neotropical forests. We measured mechanical properties from branch tips to bases, as well as the relative area and water content of bark. Using raw data and phylogenetically independent contrasts, we then tested predictions regarding trait associations with environment and mapped branch tip-to-base ontogenetic changes.• Across our wet-dry gradient, bark water storage was greater in drier habitats, whereas bark tissue mechanical rigidity was greater in the taller species of moister forests. Bark was the principal mechanical tissue in branch tips and an important contributor even in branches 3 m long. Within species, bark contributions to mechanical support and water storage came mostly through a tip-to-base increase in bark quantity rather than alterations in tissue properties. Quantitative developmental alterations in proportions of bark to wood led to habit differences.• Our clade-based approach shows that, in marked contrast to most community-based results, environment can strongly predict bark functional traits across species in ways that seem plausibly adaptive.

Relações entre volume e massa da madeira e casca de jurema-preta (Mimosa tenuiflora)

The Mimosa tenuiflora is a species typical of the Brazilian semi-arid region, used as forage, energy source, fences and with potential for production of vegetable tannins. However, there are few studies on the relationships of dendrometric parameters of species. This study aimed to evaluate the volume and mass of wood (firewood) and the volume and mass of bark in Mimosa and verify their variation during the dry and rainy seasons. Thus, were collected, on a quarterly basis, in Santa Terezinha, Paraíba, Brazil, 10 plants of Mimosa tenuiflora, a total of 40 plants, and conducted strict cubic content of wood with and without bark, measurements, determination of moisture content of wood and bark and established relations between the dendrometric parameters. It was noted that the volume and mass of wood are not related to the volume and mass of bark. Moisture content in wood and bark showed that in the months of December 2008 (beginning of the rainy season) and April 2009 (the end of rainy season) was high. In the months of December 2008 and April 2009 higher percentage of green leaves in the trees was observed, due to the occurrence of rain during the collection of the material.

Investigation of Solid Energy Potential of Wood and Bark Obtained from Four Clones of a 2-Year Old Goat Willow

To investigate solid raw material characteristics of willow (Salix caprea) bark and woody core, this study analysed overall chemical composition, monosaccharide composition, ash content, and main ash composition of both tree components. Significant differences were observed between the two in terms of chemical composition, carbohydrate composition, ash content, and major inorganics. The ash content in bark was 3.8–4.7 %, compared with 0.6–1.1 % in the woody core. Polysaccharide content in the woody core was 62.8–70.6 % but was as low as 44.1–47.6 % in the bark. The main hemicelluloses consisting of monosaccharides were xylose in the case of the woody core, and xylose, galactose, and arabinose in the case of bark. Woody core biomass of willow provides superior solid fuel raw material, as compared with bark biomass, with higher heating values, less ash content, and less slagging-causing material.

The Effects Of Casuarina Bark On Lipid Profile And Random Blood Sugar Level In Albino Rats

The effect of Casuarina equisetifolia bark incorporated into rat feed at 10-40% on the lipid profiles and blood sugar of albino rats was investigated. The rats were fed ad lib for 21 days. The parameters studied were triacylglycerol (TGL), total cholesterol (TC), total lipid (TL), phospholipids (PHOS), high-density lipoprotein (HDL) and random blood sugar (RBS). Their means were subjected to a t-Test at P 0.05) in the TGL levels of all the rats, including the control, as they all range between 0.18-0.22(mg/dl). The effects on TC and TL were irregular as they did not display any dose dependence. The mean plasma PHOS levels did not change significantly (P>0.05) between the control and the rats fed on 10% feed (0.19± 0.00 vs 0.18± 0.00 mg/dl), was significantly lowered (P 0.05) in the rats maintained on the feeds with the 20-40% bark contents. The mean HDL level rose, although insignificantly (P>0.05) with the percentage contents of the bark in the feeds; by implication, the low-density lipoprotein (LDL) was decreasing with the increase in the bark contents of the feeds-cardioprotective. The RBS also decreased as the percentage bark contents of the feeds increased, indication that it could have anti-diabetic properties.