Woody Material Research Articles

Basidiome production of ectomycorrhizal and saprophytic agaricoid fungi respond differently to forest management

Forest management generates border effects in mature dense forests. How agaricoid fungi species react to this disturbance depends on climatic and site conditions, as well as forest management system used and its intensity. We compared abundance and richness of ectomycorrhizal and saprophytic species in managed and unmanaged stands in Nothofagus pumilio (Poepp. & Endl.) Krasser forests of Patagonia, Argentina. We found that basidiome abundance and richness of ectomycorrhizal and saprophytic species were favoured by different forest structure and climatic factors. Ectomycorrhizal species basidiome production was significantly correlated to mean relative humidity of the 15 days prior to sampling and tree density (number of trees per hectare) existing prior to management activities. The latter implies that the tree density an ecosystem is capable of sustaining is crucial to the establishment of ectomycorrhizal species. Saprophytic species were favoured by the increased amount of woody material generated by logging together with maximum temperature in the 15 days prior to sampling and mean annual precipitation. Our results indicate that agaricoid fungi are not affected by low- to medium-intensity forest management, establishing the forestry level that fungal community can tolerate without loss of species in Patagonia.

Comparison of terrestrial LiDAR and digital hemispherical photography for estimating leaf angle distribution in European broadleaf beech forests

Leaf inclination plays a crucial role in regulating the radiation, carbon and water fluxes in plant canopies. Accurate measurement of the probability density function of leaf inclination (i.e., the leaf angle distribution or leaf inclination distribution function (LIDF)), is very important for modelling photosynthesis as well as measuring leaf area index. In spite of its importance, in situ measurement of LIDF is very challenging. Both digital hemispherical photography (DHP) and terrestrial LiDAR (TLS) have been used to measure LIDF. However, the consistency and relative accuracy of these two techniques has never been evaluated.In this research, we aimed to evaluate which in situ technique, either DHP or TLS, could measure LIDF more accurately, with respect to both field-based and synthetic datasets. The field-based datasets were collected from 36 natural European beech stands covering a range of forest structures. The synthetic datasets were generated from 44 virtual forest scenes using TLS and DHP simulators. Due to the inability of differing leaf and woody materials in DHP, the average plant inclination angle (θ¯) from DHP and TLS was selected for LIDF comparison. The average inclination angle (θ¯) was retrieved from TLS point clouds using a geometric method, and from DHP using three gap fraction inversion methods including the NC method (Norman and Campbell, 1989), as well as the CAN-EYE and Hemisfer software.Results from the field-based datasets showed a significant difference and inconsistency between the average inclination angle (θ¯) retrieved from TLS and DHP (respectively θ¯∈(40°, 58°) from TLS, (15°, 86°) from DHP NC, (36°, 78°) from DHP CAN-EYE, (0°, 67°) from DHP Hemisfer). Results from the synthetic datasets demonstrated that the accuracy of θ¯ from TLS was considerably higher than that obtained from DHP (R2: 0.90 > 0.74; RMSE: 5.38° < 13.30°).This study demonstrated that the LIDF estimated from TLS and DHP were not coherent. Based on the experimental results as well as deduction from theoretical arguments, we recommended using TLS when measuring leaf inclination in broadleaf forests, especially for stands with a heterogeneous structure.

Small-mammal abundance differs between pipelines, edges, and interior boreal forest habitat

Oil and gas development alters boreal forests by creating early-successional habitat and an increased amount of edge. We evaluated which small-mammal species used pipeline rights of way, the influence of vegetation recovery on pipelines, and edge effects in the adjacent forest. Meadow voles (Microtus pennsylvanicus (Ord, 1815)) were the most common species on pipelines, whereas adjacent forest was dominated by southern red-backed voles (Myodes gapperi (Vigors, 1830)), northern red-backed voles (Myodes rutilus (Pallas, 1779)), and North American deer mice (Peromyscus maniculatus (Wagner, 1845)). Deer mouse abundance was greater along pipeline transects with greater vegetation recovery. Within the forest, irrespective of vegetation recovery on pipelines, meadow voles and deer mice increased near edges. Red-backed voles showed a mixed (i.e., neutral or positive) response to edge. Vegetation variables (i.e., canopy type and cover, ground cover, stem counts, and volume of downed woody material) were important predictors of small-mammal abundance in the forest, but they could not fully account for observed edge effects. Altered small-mammal communities on and adjacent to pipelines may have implications for boreal forest management and conservation through potential changes in predator–prey dynamics and boreal food webs; these implications require further study.

Processing high-performance woody materials by means of vacuum-assisted resin infusion technology

High-performance materials derived from natural wood have been vigorously developed, however, their commercialized products are very limited owing to the lack of industrial production efficiency and increase of environmental concern. This study is aimed at developing a clean process for large-scale production of high-performance woody materials without involving any chemical methods. The industrialized vacuum-assisted resin infusion (VARI) process was initially applied to solid wood for manufacturing woody materials with excellent flexural performances. VARI process can provide better control over harmful volatiles generated by resins than that of the traditional open mold techniques, making them compliant with “clean production”. The porosity was reduced from 66.0% to 33.8% after infusing epoxy into wood through the VARI process, and further reduced to 22.6% after being compressed. The flexural modulus and strength were significantly increased by 142.2% and 142.8%, respectively. The flexural strength (304.9 MPa) reached the range of alloy, between Alloy 2024-T3 (345 MPa) and Steel alloy 1040 (260 MPa). Due to its relatively low density, the specific flexural strength was only slightly lower than diamond. The dramatic reduction of porosity was deemed to be the major contribution to those improvements. The fabrication of high-performance woody materials does not use chemical treatment; therefore, it could be considered as a clean production. Additionally, the contribution to clean production of this study was further confirmed by life-cycle assessment (LCA). The comparisons of environmental impacts of the woody material, steel alloy and aluminum alloy were carried out using LCA, revealing that the global warming, acidification, human health (HH) cancer, HH noncancer, HH criteria air pollutants, eutrophication, ecotoxicity, smog, natural resource depletion, habitat alteration, and ozone depletion, were reduced by 1.72–667.06 times when the woody material was used to replace steel alloy, while were reduced by 7.34–636.21 times when the woody material was utilized to replace aluminum alloy, respectively.

Fisher accessibility and habitat complexity influence the distribution of adult Cherax cainii (Decapoda: Parastacidae) in a water supply reservoir

Abstract Almost one third of all freshwater crayfishes are threatened with extinction. The factors influencing the distribution of freshwater crayfishes in lentic systems are poorly understood, hampering the conservation and enhancement of those populations. Cherax cainii is the third largest freshwater crayfish in the world and is endemic to south‐western Australia. The distribution of the species has declined markedly, largely attributable to secondary salinization and habitat decline. There is the potential for population enhancement through habitat restoration and the restocking of reservoirs that act as important non‐salinized refuges; however, there is limited understanding of the distribution and habitat associations of C. cainii in these systems. Mark–recapture was undertaken to determine the population abundance and fine‐scale distribution of C. cainii in a large reservoir over a 5‐month period, with generalized linear mixed modelling used to determine those factors that explained the variation in its distribution. Cherax cainii distribution in the reservoir was positively associated with complex habitat (large woody material) and the level of inaccessibility to humans, and negatively associated with depth. The population had a non‐uniform distribution within the reservoir with significant hot‐ and cold‐spots present and there was limited distance between recaptures during the coolest period of the year. The findings suggest that C. cainii would benefit from the provision of additional complex habitat in such habitat depauperate reservoirs to provide increased shelter from predators. It may also be vulnerable to localized depletion through legal and illegal fishing pressure. The study highlights the importance of understanding habitat preferences and movement patterns of freshwater crayfish to underpin their conservation.

Surface fuel loads following a coastal–transitional fire of unprecedented severity: Boulder Creek fire case study

British Columbia experienced three years with notably large and severe wildfires since 2015. Multiple stand-replacing wildfires occurred in coastal–transitional forests, where large fires are typically rare, and thus, information on post-fire carbon is lacking. Because of their carbon storage potential, coastal–transitional forests are important in the global carbon cycle. We examined differences in surface fuel carbon among fire severity classes in 2016, one year after the Boulder Creek fire, which burned 6 735 ha of coastal–transitional forests in 2015. Using remotely sensed indices (dNBR), we partitioned the fire area into unburned (control), low-, moderate-, and high-severity classes. Field plots were randomly located in each class. At each plot, surface fuel carbon was quantified by type, namely coarse, small, and fine woody material, duff, and litter, and carbon mass by fuel type was compared among severity classes. Total surface fuel carbon did not differ significantly between burned and unburned plots; however, there was significantly less duff and litter carbon in burned plots. Remotely sensed severity classes did not properly capture wildfire impacts on surface fuels, especially at lower severities. Pre-fire stand characteristics are also important drivers of surface fuel loads. This case study provides baseline data for examining post-fire fuel carbon dynamics in coastal–transitional British Columbia.

A Density-Based Approach for Leaf Area Index Assessment in a Complex Forest Environment Using a Terrestrial Laser Scanner

Forests are an important part natural ecosystems, by for example providing food, fiber, habitat, and biodiversity, all of which contribute to stable natural systems. Assessing and modeling the structure and characteristics of forests, e.g., Leaf Area Index (LAI), volume, biomass, etc., can lead to a better understanding and management of these resources. In recent years, Terrestrial Laser Scanning (TLS) has been recognized as a tool that addresses many of the limitations of manual and traditional forest data collection methods. In this study, we propose a density-based approach for estimating the LAI in a structurally-complex forest environment, which contains variable and diverse structural attributes, e.g., non-circular stem forms, dense canopy and below-canopy vegetation cover, and a diverse species composition. In addition, 242 TLS scans were collected using a portable low-cost scanner, the Compact Biomass Lidar (CBL), in the Hawaii Volcanoes National Park (HAVO), Hawaii Island, USA. LAI also was measured for 242 plots in the site, using an AccuPAR LP-80 ceptometer. The first step after cleaning the point cloud involved detecting the higher forest canopy in the light detection and ranging (lidar) point clouds, using normal change rate assessment. We then estimated Leaf Area Density (LAD), using a voxel-based approach, and divided the canopy point cloud into five layers in the Z (vertical) direction. These five layers subsequently were divided into voxels in the X direction, where the size of these voxels were obtained based on inter-quartile analysis and the number of points in each voxel. We hypothesized that the intensity returned to the lidar system from woody materials, like branches, would be higher than from leaves, due to the liquid water absorption feature of the leaves and higher reflectance for woody material at the 905 nm laser wavelength. We also differentiated between foliar and woody materials using edge detection in the images from projected point clouds and evaluated the density of these regions to support our hypothesis. Density of points, or the number of points divided by the volume of a grid, in a 3D grid size of 0.1 m, was calculated for each of the voxels. The grid size was determined by investigating the size of the branches in the lower portion of the canopy. Subsequently, we fitted a Kernel Density Estimator (KDE) to these values, with the threshold set based on half of the area under the curve in each of the density distributions. All the grids with a density below the threshold were labeled as leaves, while those grids above the threshold were identified as non-leaves. Finally, we modeled LAI using the point densities derived from the TLS point clouds and the listed analysis steps. This model resulted in an R 2 value of 0.88. We also estimated the LAI directly from lidar data using the point densities and calculating LAD, which is defined as the total one-sided leaf area per unit volume. LAI can be obtained as the sum of the LAD values in all the voxels. The accuracy of LAI estimation was 90%, with an RMSE value of 0.31, and an average overestimation of 9 % in TLS-derived LAI, when compared to field-measured LAI. Algorithm performance mainly was affected by the vegetation density and complexity of the canopy structures. It is worth noting that, since the LAI values cannot be considered spatially independent throughout all the plots in this site, we performed semivariogram analysis on the field-measured LAI data. This analysis showed that the LAI values can be assumed to be independent in plots that are at least 30 m apart. As a result, we divided the data into six subsets in which the plots were 30 m spaced. The R 2 values for these subsets, based on modeling of the field-measured LAI using leaf point density values, ranged between 0.84–0.96. The results bode well for using this method for efficient, automatic, and accurate/precise estimation of LAI values in complex forest environments, using a low-cost, rapid-scan TLS.

Planted forests for open coal mine spoils rehabilitation in Colombian drylands: Contributions of fine litterfall through an age chronosequence

The contributions of organic matter via fine litterfall to the soil were evaluated in three sites that were rehabilitated 7, 10, and 21 years earlier, respectively, located in an opencast coalmine at El Cerrejón (La Guajira, Colombia). We placed forty litterfall traps in four plots at each reclaimed site and in a tropical dry mature forest, which was used as a reference ecosystem. Fine litterfall (including woody material up to 2 cm in length) was collected monthly from October 2013 to November 2014. Values for the highest fine litterfall recorded in the 21-year-old site (2.3 Mg ha−1 year−1) were more than double those recorded in the 7-year-old site (1.1 Mg ha−1 year−1). Soil carbon and nitrogen contents were greater in the rehabilitated sites than in the unrestored substrate. Soil phosphorus (P) increased significantly 7 years after rehabilitation. The high return of organic matter and nutrients via fine litterfall in the three rehabilitated sites suggests that the rehabilitation approach employed in this opencast coalmine was successful in terms of enriching soil organic matter content and nutrient status and that it could serve as a model for the rehabilitation of similarly degraded mining habitats.

Opportunities and attitudes of private forest landowners in supplying woody biomass for renewable energy

Woody biomass has been identified as a source of dispatchable, renewable energy. Private lands supply the majority of the wood-based pellets that is produced in the southeastern United States (SE US) and shipped to countries in the European Union (EU) for energy generation. To assess the perspectives of potential suppliers of woody biomass in the SE US, nonindustrial private forest landowners were surveyed in the fuelsheds of the two primary ports for wood pellets exported to the EU. The survey assessed owners' characteristics, attitudes, and future management plans. Survey results were examined to explore the relationships among these factors and owners' intentions for providing material for wood-based energy. The results indicate that forest landowners have multiple reasons for maintaining their forest land, with more than 40% of the owners ranking timber production as a very important reason. Furthermore, the majority of landowners would be willing to provide woody biomass for producing bioenergy. Among factors that would enhance landowners' willingness to provide woody biomass for energy, technical assistance to improve stand productivity and future value was the most popular option, followed by reducing fire and disease risk, long-term markets, and high prices. Landowner willingness to provide woody material for bioenergy also varied depending on demographics including age and gender, property characteristics including holding size and distance to residence, and perceptions regarding the impact on forest value of wood pellet demand and the viability of bioenergy as an alternative to fossil energy.

The impact of Quaternary sea-level changes on the sedimentary organic matter of the Paraíba do Sul Deltaic Complex area, southeastern Brazil

The Paraíba do Sul Deltaic Complex (PSDC) landscapes diversified markedly over the last 123,000 years B.P. The PSDC is characterized by non-marine to marine deposits, and very complex non-marine deposits in its uppermost part. In such a setting, the characterization of the sedimentary organic matter is a useful tool for conduction paleoenvironmental reconstruction. Sea level changes during this interval are reflected in the stratigraphic distribution of sedimentary organic matter recorded in the four sections of the onshore portion of Campos Basin, southeastern Brazil. The succession is dominated by the woody material (phytoclasts), related to a continuous terrigenous input on the area and is characterized by a long-term regressive trend. The stratigraphical distribution of five palynofacies association reveal a wide variety of depositional paleoenvironments. The palynofacies associations attributed to alluvial fan, fluvial, shallow marine and lagoon were recognized. The alluvial fan, in the lowermost part of the succession, is characterized by high contents of opaque and pseudoamorphous particles. The fluvial deposits, in the lower and uppermost parts of the succession, are dominated by wood material (non-opaque) and sporomorphs. The marine deposits (shallow marine and lagoon), in the middle parts of the succession, appear to be related to the dinoflagellate cysts, microforaminifera linings and amorphous organic matter and suggest a notable marine incursion.

Wood Modification by Furfuryl Alcohol Resulted in a Delayed Decomposition Response in Rhodonia ( Postia ) placenta

The aim of this study was to investigate differential expression profiles of the brown rot fungus Rhodonia placenta (previously Postia placenta) harvested at several time points when grown on radiata pine (Pinus radiata) and radiata pine with three different levels of modification by furfuryl alcohol, an environmentally benign commercial wood protection system. The entire gene expression pattern of a decay fungus was followed in untreated and modified wood from initial to advanced stages of decay. The results support the current model of a two-step decay mechanism, with the expression of genes related to initial oxidative depolymerization, followed by an accumulation of transcripts of genes related to the hydrolysis of cell wall polysaccharides. When the wood decay process is finished, the fungus goes into starvation mode after five weeks when grown on unmodified radiata pine wood. The pattern of repression of oxidative processes and oxalic acid synthesis found in radiata pine at later stages of decay is not mirrored for the high-furfurylation treatment. The high treatment level provided a more unpredictable expression pattern throughout the incubation period. Furfurylation does not seem to directly influence the expression of core plant cell wall-hydrolyzing enzymes, as a delayed and prolonged, but similar, pattern was observed in the radiata pine and the modified experiments. This indicates that the fungus starts a common decay process in the modified wood but proceeds at a slower pace as access to the plant cell wall polysaccharides is restricted. This is further supported by the downregulation of hydrolytic enzymes for the high treatment level at the last harvest point (mass loss, 14%). Moreover, the mass loss does not increase during the last weeks. Collectively, this indicates a potential threshold for lower mass loss for the high-furfurylation treatment.IMPORTANCE Fungi are important decomposers of woody biomass in natural habitats. Investigation of the mechanisms employed by decay fungi in their attempt to degrade wood is important for both the basic scientific understanding of ecology and carbon cycling in nature and for applied uses of woody materials. For wooden building materials, long service life and carbon storage are essential, but decay fungi are responsible for massive losses of wood in service. Thus, the optimization of durable wood products for the future is of major importance. In this study, we have investigated the fungal genetic response to furfurylated wood, a commercial environmentally benign wood modification approach that improves the service life of wood in outdoor applications. Our results show that there is a delayed wood decay by the fungus as a response to furfurylated wood, and new knowledge about the mechanisms behind the delay is provided.

Amplitud forrajera de la hormiga escamolera (Liometopum apiculatum Mayr, Hymenoptera: Formicidae) en una zona semiárida del altiplano zacatecano

En México, la hormiga escamolera (Liometopum apiculatum Mayr) es un recurso natural económicamente importante. Sin embargo, sus colonias son sobre utilizadas. Tanto su hábitat como su actividad forrajera son aspectos poco estudiados. El objetivo de este estudio fue determinar la amplitud forrajera de L. apiculatum y las variables del hábitat que la definen en Villa González Ortega, Zacatecas, México. Durante 2014, se localizaron 31 colonias de L. apiculatum. La amplitud forrajera de la hormiga se determinó mediante la identificación de los caminos de forrajeo, sus distancias desde el nido a los sitios de forrajeo y sus azimuts. Las variables del hábitat que más se asociaron con la amplitud forrajera se determinaron con índices de Frecuencia de observación (Fo), análisis cladístico (AC) y análisis de correspondencia canónica (ACC). La hormiga escamolera forrajeó en un área de tamaño promedio de 1 565.65 ± 535.63 m2 y las variables que más explicaron esta superficie forrajera fueron la presencia de Agave salmiana, Yucca spp., Prosopis spp., Acacia farnesiana, suelo desnudo, material leñoso y cobertura de arbustos. Este estudio, sobre la amplitud forrajera de la hormiga escamolera, proporciona información para el diseño de estrategias de manejo y conservación de sus poblaciones y hábitats en México.

Compost Feedstock and Compost Acidification Affect Growth and Mineral Nutrition in Northern Highbush Blueberry

New markets for organic northern highbush blueberry (Vaccinium corymbosum L.) have stimulated interest in using composts specifically tailored to the plant’s edaphic requirements. Because composts are typically neutral to alkaline in pH (pH 7 to 8), and blueberry requires acidic soil (pH 4.2 to 5.5), we investigated elemental sulfur (S0) addition as a methodology for reducing compost pH. The objectives were to 1) characterize initial compost chemistry, including the pH buffering capacity of compost (acidity required to reduce pH to 5.0), 2) measure changes in compost chemistry accompanying acidification, and 3) evaluate plant growth and mineral nutrition of blueberry in soil amended with an untreated or acidified compost. Ten composts prepared from diverse feedstocks were obtained from municipalities and farms. Addition of finely ground S0 reduced compost pH from 7.2 to 5.3, on average, after 70 d at 22 °C, and increased the solubility of nutrients, including K (from 22 to 36 mmol(+)/L), Ca (from 5 to 19 mmol(+)/L), Mg (from 5 to 20 mmol(+)/L), and Na (from 6 to 9 mmol(+)/L). Sulfate-S, a product of S0 oxidation, also increased from 5 to 45 mmol(−)/L. The composts were incorporated into soil at a high rate (30% v/v) in a greenhouse trial to evaluate their suitability for use in blueberry production. Shoot and root growth were strongly affected by compost chemical characteristics, including pH and electrical conductivity (EC). Potassium in compost was highly variable (2–32 g·kg−1). Concentration of K in the leaves increased positively in response to compost K, whereas shoot dry weight and root growth declined. Leaf Mg also declined in response to compost K, suggesting that elevated K concentrations in compost may cause Mg deficiency. Composts with the highest K were also high in total N, pH, and EC. Compost acidification to pH ≤ 6 improved growth and increased leaf Mg concentration. On the basis of these results, composts derived from animal manures or young plant tissues (e.g., green leaves) appear to be unsuitable for high-rate applications to blueberry because they usually require high amounts of S0 for acidification and are often high in EC and K, whereas those derived from woody materials, such as local yard debris, appear promising based on their C:N ratio, compost acidification requirement, and EC.

Comparative Assessment of Biochar Stability Using Multiple Indicators

Biochar application is one strategy proposed to improve carbon sequestration in soil. Maintaining high carbon content in soil for a long period requires stable biochar. In this work, we assessed biochar stability by two methodologies, i.e., laboratory incubation and chemical oxidation. Biochar was produced at four different temperatures (400 °C, 500 °C, 600 °C, and 800 °C) from rice (Oryza sativa L.) straw and husk, applewood branch (Malus pumila), and oak (Quercus serrata Murray) residues. Results showed that the high-temperature biochars were more stable in both abiotic and biotic incubations, whereas the low-temperature biochars had reduced longevity. In addition, we showed biochars originated from woody material have higher stable carbon than those produced from rice residues. Finally, the oxidative assessment method provided a more reliable estimation of stability than the biotic incubation method and showed a strong correlation with other stability indicators.

Anellotech’s pilot is producing aromatics

Anellotech says it has validated its technology to make biobased aromatic chemicals from loblolly pine biomass at its pilot plant in Silsbee, Texas. The company’s technology pretreats the woody material and converts it to aromatics in a catalytic reactor. The process yields a mixture of benzene, toluene, xylene, other distillates, and carbon monoxide. In the pilot, yields of liquid products were 22–24% by weight of the feedstock. Anellotech says it is working to raise funds for a commercial facility and also hopes to license its technology to other companies.

Mesopore structure in Camellia Oleifera shell.

Generally, Camellia oleifera shells are byproducts of edible oil production and are often incinerated or discarded as agricultural waste without any sustainable uses. Although numerous studies have focused on the C. oleifera shell, few studies have examined its biological characteristics, particularly its internal mesoporosity. The aim of the present study was to elucidate the microscopic biological structure of C. oleifera shells to explore their potential applications. Paraffin-embedded slices of C. oleifera shells were observed on different planes using an optical microscope. Supercritically dried samples were prepared and assessed using the nitrogen adsorption-desorption technique to reveal mesopore structural features. The present article shows that C. oleifera shells were mainly made up of stone cells, parenchyma tissue, spiral vessels, and vascular bundles. The key features of the cells were the pits in the cell walls of stone cells and vessels, which are associated with the abundant mesopores in C. oleifera shells. C. oleifera shells have an advantage over woody materials based on their mesoporosity features. C. oleifera shells are ideal raw materials that could serve as biomass templates or find applications as other high-performance biomimetic materials.

Towards sustainable thermoplastic woody materials prepared from continuous steam explosion followed by oxidation-reduction

Converting plant fibers into thermoplastic materials are challenging in a sustainable society. Herein, continuous steam explosion pretreatment was used to improve the reactivity of plant fiber. Meanwhile, periodate oxidation and subsequent sodium borohydride reduction were used to plastify plant fiber. SEM and BET results showed that steam explosion pretreatment can gradually dissociate bundle structure of eucalyptus fiber and increase its specific surface area, which improve the reaction efficiency significantly. The FTIR and NMR indicated that the eucalyptus fiber had been successfully oxidized and reduced. XRD and TGA tests showed that the crystallinity and thermal stability of the modified fibers decreased with the increase of oxidation time. When the oxidation time is 8 h, the mechanical properties of the modified material are optimal, and the glass transition temperature is significantly reduced. These results suggest that this all-component plant fiber material is a possible alternative to petroleum-based materials.

Caracterização dos planos de manejo florestal no estado do Piauí

A lenha é um dos mais importantes produtos florestais da região Nordeste do Brasil, e cada vez mais é necessário que sua exploração seja feita de maneira sustentável. Nesse sentido, o manejo florestal tem sido uma proposta de significativa melhoria das características ambientais dessa atividade. Este trabalho teve como objetivo identificar e analisar a atividade de exploração florestal por meio de Planos de Manejo Florestal Sustentável (PMFS) no estado do Piauí. Foram analisados dados de localização e produção, no período de 2010-2015. O diagnóstico dos PMFS do Piauí foi realizado por meio de consulta ao banco de dados da coordenação de licenciamento da Secretaria Estadual de Meio Ambiente e Recursos Hídricos – SEMAR, no período de janeiro a março de 2016. Os 96 PMFS detentores de autorização representaram 117.510,60 hectares de área manejada, em propriedades cujas extensões variaram de 67,60 a 34.208,00 ha, com área manejada por propriedade entre 40,00 e 24.969,00 ha. Os talhões adotados para a exploração anual tiveram dimensões entre 7,50 e 1.945,70 ha. O volume anual autorizado, no período, foi de 1.998.986,20 st/ano. A análise dos planos indica que o estado do Piauí possui capacidade de abastecimento de matriz energética proveniente de material lenhoso oriundo do manejo florestal, e que esta atividade, ainda, resulta em significativo benefício ambiental, pelo potencial de sustentabilidade que apresenta.

Formaldehyde-Free Wood Composite Fabricated Using Oil Palm Starch Modified with Glutardialdehyde as the Binder

Oil palm trunk is a kind of biomass rich in starch content. Oil palm trunk waste was available throughout the year in Malaysia and Indonesia due to continuous felling of nonproductive, over 25-year-old trees. Even though some manufacturers were using it in plywood and veneer production, they are hard to handle which later becomes less favorable raw materials due to a high moisture content where combination with a high starch content quickly attracts fungus and wood-decaying agents. The objective of this work was to evaluate properties of experimental wood composite panels, manufactured using oil palm-extracted starch modified with glutardialdehyde (OPSMG) as a binder. Different analyses were employed to characterize the properties of the samples besides evaluation of bending, internal bonding strength, and dimensional stability of the panels. Characterization on the functional group using the FT-IR analysis showed presence of aldehyde groups and ketone stretching vibrations at 1736.05 cm−1 and 1596.25 cm−1, which proves the presence of glutardialdehyde besides formation of bonding between the OPSMG and the woody materials. The XRD analysis showed the starch modification had lowered the crystallinity index which in turn increased the strength of the manufactured wood composites. The OPSMG wood composites were also found to have lower thermal stability, as evaluated using the TGA analysis. It was recorded that the maximum modulus of rupture for OPSMG wood composites was achieved at the 0.80 g/cm3 density level with an average value of 15.446 N/mm2 which showed 38.00% increment in strength between those two types of wood composites. Thickness swelling after immersion in water can still be improved by incorporating the moisture-repellent material later. After analyzing the results, it was concluded that modified oil palm starch has the potential to be used as an environment friendly binder for wood composite making.

Induced antimicrobial activity in heat‐treated woodchips inhibits the activity of the invasive plant pathogen Phytophthora ramorum

The antimicrobial activity of heat‐treated woodchips of three woody host species against the invasive oomycete plant pathogen Phytophthora ramorum was investigated to assess the potential of heated woodchips to suppress disease. Results demonstrated that heat‐treated woodchips of pine (Pinus sylvestris), Japanese larch (Larix kaempferi) and rhododendron (Rhododendron ponticum) inhibited recovery of P. ramorum spores and mycelium compared with similar material that had only been air‐dried. Effects were most evident with pine and larch; inhibition was maintained even when larch woodchips were diluted with soil. In vitro assays using methanol crude extracts from woodchips of the three species showed they all had an inhibitory effect on P. ramorum zoospores and reduced chlamydospore germination compared with air‐dried wood extracts. Chemical analysis of the extracts revealed several induced compounds were present but in different concentrations for each species. Coniferaldehyde was the most active inhibitor against spores and mycelium, while the dominant resin acids, dehydroabietic and abietic acid, decreased the minimum inhibitory concentration of phenolic compounds tested against P. ramorum but were ineffective when used alone. An array of compounds, including dehydroabietic acid, methyl abietate, α‐pinene and 3‐carene, occurred at elevated levels in the living tissue of Japanese larch bark attacked by P. ramorum. These compounds may be part of the induced resistance response of larch to P. ramorum. Results of a field trial using heat‐treated and air‐dried woodchips were consistent with the crude extract bioassay results, suggesting that heat‐treated woody materials have potential to reduce the survival of P. ramorum under natural conditions.