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The aim of the study was to assess the impact of the duration of the use of a biofiltration bed on the efficiency of biofiltration of sulphur compounds and on the physicochemical and microbiological properties of the bed. The study was carried out at an animal waste treatment plant. Two biofiltration chambers (beds A and B) filled with different organic mixtures (compost soil, peat, coconut fibre and oak bark) were used in the biofilter. Chromatographic analysis showed a very high rate of effectiveness in the first study period, irrespective of the packaging material used. The best effects were obtained for inorganic sulphur compounds (above 99%). The duration of use of the bed material was shown to affect the efficiency of biofiltration. After 3 years of operation, thiol degradation efficiency fell below 50%. The biological decomposition of inorganic compounds (H2S + SO2) was 73% and 59.6% in beds A and B, respectively. Analysis of the biofiltration material indicated stabilization of its physicochemical parameters. Numbers of bacteria were not found to be depend on the duration of use or the type of filtering media.

The application of high-throughput nucleic acid and protein sequencing technologies is transforming our understanding of plant microbiomes and their interactions with their hosts in health and disease. However, progress in studying host-microbiome interactions in above-ground compartments of the tree (the phyllosphere) has been hampered due to high concentrations of phenolic compounds, lignin, and other compounds in tree bark that severely limit the success of DNA, RNA, and protein extraction. Here we present modified sample-preparation and kit-based protocols for the extraction of host and microbiome DNA and RNA from oak (Quercus robus and Quercus petraea) bark tissue for subsequent high-throughput sequencing. In addition, reducing the quantity of bark tissue used for an established protein extraction protocol yielded high quality protein for parallel analysis of the oak-microbiota metaproteome. These procedures demonstrate the successful extraction of nucleic acids and proteins from oak tissue using as little as 50 mg of sample input, producing sufficient quantities for nucleic acid sequencing and protein mass spectrometry of tree stem tissues and their associated microbiota. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.

Airborne Cs-137 originated from the nuclear tests in the atmosphere and from the Chernobyl nuclear disaster was retained by the trees biomass and nowadays it can still be found in various concentrations in tree barks from Romania and other European countries. This study brings the first results of Cs-137 presence in tree bark from Romania on different considerations: (i) data dispersion in spruce and oak bark from NW, SW and central Romania, and the spatial variability of Cs-137 within oak and spruce bark from a natural protected forest area from Balvanyos area (Covasna County), known to be highly affected by the Chernobyl nuclear release; (ii) comparison of Cs-137 content in different tree bark species (oak, spruce, poplar and cherry); (iii) differences in Cs-137 concentrations with the bark depth layers and around the tree trunk; and (iv) comparison of mean Cs-137 values in spruce/oak bark from Romania with data from other European countries. (C) 2015 Elsevier Ltd. All rights reserved.

The woodworking industry generates a great amount of bark which has not yet found a wider industrial application. None of the previously conducted research has considered oak bark application (which is one of the most often processed wood species in Poland) as a filler for wood adhesives. Moreover, no studies have determined the properties of bark containing melamine-urea-formaldehyde resin (MUF), which increasingly replaces pure urea-formaldehyde adhesives. Thus, the aim of the study was to determine the possibility of grinded oak bark application as a filler for MUF adhesive in plywood manufacturing. The chemical composition of oak bark was evaluated. Properties of liquid resins, such as viscosity, gel time, pH, and solid content, were determined. Chemical interaction between the filler and resin was assessed with using Fourier-transform infrared (FTIR) spectroscopy. Plywood panels manufactured using MUF adhesive filled with different bark concentrations (10%, 15%, 20%, 25%) were tested in terms of such properties as formaldehyde release and bonding quality. Studies have shown an improvement in liquid resin properties. The course of FTIR spectra did not explain the chemical interaction between the polymer and the filler. The addition of oak bark at a concentration of 15% made it possible to produce plywood panels characterized by reduced formaldehyde release and improved bonding quality.

Gonultas, Oktay/0000-0002-2132-4667; Candan, Zeki/0000-0002-4937-7904 WOS: 000427790000004 Bark as a biowaste has a huge availability throughout the world and has had limited use in industrial applications. Black pine bark and oak bark were considered in this work. The aim was to manufacture a new biocomposite with different combination of black pine bark, oak bark, polypropylene, polyethylene, and a coupling agent, and to determine some physical and mechanical properties of the manufactured biocomposites. Density, thickness swelling, water absorption, tension strength, modulus of rapture and modulus of elasticity in bending and tension of the biocomposites were determined. According to the results, thickness swelling and water absorption properties were improved up to 80% when compared with wood-plastic composites (WPC) produced with wood flour. Although the new biocomposites displayed lower mechanical performance in comparison of biocomposites made with wood flour, the observed results were satisfactory. Based on the results of this study, black pine bark and oak bark can be used as filler materials in WPCs production. Hereby, these bark materials can be the raw material for value-added products. Bark use in biocomposite production also can contribute to reduced requirements of wood material and petroleum products.

In the present study, the bark of oak trees (Quercus petraea Liebl.) was collected from Belgrade Forest northwest of Istanbul for determination of 137Cs, 40K, 232Th, and 238U activity. A gamma spectrometer equipped with high-purity germanium detector was used for radioactivity measurement. Bark samples were collected from the northern and southern sides of trees at a height of 1.5 m above the ground in order to see the effects of rainfall and wind; and they were also collected from the northern side at a height of 0.5 m above the ground to assess the effect of soil splash. The activity concentrations of 137Cs, 40K, 232Th, and 238U in the bark samples were found to vary in the range of 1.40-27.50, 45.0-221.2, 0.92-9.64, and 4.04-36.10 Bq/kg, respectively. The elevated activity of 238U in bark samples could be attributed to a large amount of coal combustion in the region until the 1990s. According to one-way ANOVA, a significant difference was not found in bark samples collected at a height of 0.5 m and 1.5 m above the ground in terms of radionuclide activity. There was also no significant variation regarding radionuclide accumulation between northern and southern sides.