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1.
The goal of this study was to characterise chemical and histochemical properties of five dipterocarp timber wood species (Dipterocarpus kerrii, Hopea plagata, Parashorea malaanoman, Shorea almon, and Shorea contorta) differing in wood service life and utilisation. Wood of H. plagata, the most durable species, contained the lowest concentrations of nitrogen and ligno-protein, the highest C/N ratio and the lowest lignin concentration per dry mass but the highest lignin and extractive concentrations per wood density. FTIR spectroscopic studies of wood and isolated lignins of D. kerrii and H. plagata revealed differences compared to P. malaanoman and Shorea sp., which are species with short service life. Lignins of the Shorea/Parashorea species had a higher G/S ratio than those of H. plagata and D. kerrii. This was also evident from histochemical staining. Principle component analysis of FTIR spectra identified differences in both lignin composition and ligno-protein content as major source of variation.  相似文献   

2.

Background  

Thornscrubs are a vegetation type from Northeast Mexico, consisting of 60 to 80 tree and shrub species that are used for a wide range of constructive, decorative and energy purposes. However, basic research of the physical and mechanical wood properties are still needed to establish additional uses and, thereby, increase their value in the timber industry.  相似文献   

3.
The inbuilt unique properties of DNA within the timber could serve as tracking and monitoring tools to verify the legality of a suspected timber in the context of illegal logging, forest certification and chain of custody certification. By using Neobalanocarpus heimii (Dipterocarpaceae) as an example, a population identification database and haplotype distribution map in Peninsular Malaysia were generated for authenticity testing based on four chloroplast DNA markers (trnL intron, trnG intron, trnK intron and psbK-trnS spacer). Twenty one haplotypes were identified from 10 significant intraspecific variable sites. The results clearly revealed that only northern and southern regions of Peninsular Malaysia were distinguishable. Thus, this database could only be used to determine the wood lot of unknown origin at the regional level. Statistical procedure based on the composition of wood lot was used to test whether a suspected timber conforms to a given regional origin. Overall, the observed type I and II errors of the database showed good concordance with the predicted 5% threshold, which might indicate that the database is useful to reveal provenance and establish conformity of wood lot from northern and southern regions of Peninsular Malaysia. Applications of this database for timber tracking are discussed.  相似文献   

4.
Juvenile wood (JW) of conifers is often associated with compression wood (CW), with which it is sometimes believed to be identical. To determine whether JW and CW can be distinguished metabolically, we compared gas chromatographic profiles of 25 polar metabolites from rooted cuttings of a single loblolly pine (Pinus taeda L.) clone raised in controlled environment chambers and subject to three treatments: (1) grown erect with minimal wind sway (control); (2) swayed by wind from oscillating fans; and (3) with 30-cm growth increments successively bent at an angle of 45 degrees to the vertical. Profiles were compared by principal component analysis. Substantial increases in abundances of coniferin and p-glucocoumaryl alcohol separated immature JW-forming xylem tissues of the control trees from the CW-forming xylem of the bent and swayed trees.  相似文献   

5.
A new C-glucoside of epsilon-viniferin, named diptoindonesin A (1), was isolated from the ethyl acetate extract of the tree bark of Shorea seminis, together with the known stilbene oligomers (-)-ampelopsin A (2), (-)-alpha-viniferin (3), and (-)-hopeaphenol (4). The structure of 1 was determined from spectroscopic evidence.  相似文献   

6.
Amplified fragment length polymorphism (AFLP) is a powerful DNA fingerprinting technique for studying genetic rela-tionships and genetic diversity in insects. However, the crucial prerequisite for AFLP analysis is to extract DNA of high quality. In this study, we evaluate four different protocols (SDS method, improved SDS method, CTAB method and a complex method with SDS and CTAB) for isolating DNA from the seabuckthorn carpenter moth (Holcocerrus hippophaecolus (Lepidoptera: Cossidae)). The results indicate that the CTAB method does not produce DNA suitable for AFLP analysis. The SDS method and the complex method with SDS and CTAB are comparatively time-consuming and resulted in low yields of DNA and were therefore not used for AFLP assay. The improved SDS method is recommended for preparing DNA templates from H. hippophaecolus for AFLP analysis.  相似文献   

7.
Amplified fragment length polymorphism (AFLP) is a powerful DNA fingerprinting technique for studying genetic relationships and genetic diversity in insects. However, the crucial prerequisite for AFLP analysis is to extract DNA of high quality. In this study, we evaluate four different protocols (SDS method, improved SDS method, CTAB method and a complex method with SDS and CTAB) for isolating DNA from the seabuckthorn carpenter moth (Holcocerrus hippophaecolus (Lepidoptera: Cossidae)). The results indicate that the CTAB method does not produce DNA suitable for AFLP analysis. The SDS method and the complex method with SDS and CTAB are comparatively time-consuming and resulted in low yields of DNA and were therefore not used for AFLP assay. The improved SDS method is recommended for preparing DNA templates from H. hippophaecolus for AFLP analysis.  相似文献   

8.
Remediation of copper-based alkaline copper quat (ACQ) and micronized copper quat (MCQ) wood-preservative-treated weathered southern pine mulch samples by monoethanolamine (Mea) extraction was studied. The potential reuse of Mea extract in ACQ wood preservative application was also evaluated. Continuous column extraction of copper-preservative-treated samples for 32 h, using 12 % Mea removed 66–86 % (between top and bottom of the column) and 65–80 % of Cu, respectively, from ACQ- and MCQ-treated wood. Mea extracts of treated wood could be reused in ACQ-treating solutions that met the American Wood Protection Association standard specifications for ACQ wood preservatives. This was achieved either by mixing the extract with industrial Cu–Mea solution at 1:4 ratio or by adding cupric acetate salt directly into the Mea extract. ACQ-treating solutions reformulated using Mea extracts of ACQ- and MCQ-treated wood performed similarly to wood treated with industrial ACQ solution and freshly prepared solution using cupric acetate. All treated wood had similar penetrations of Cu in wood during preservative treatment, Cu leaching from the treated wood in contact with water, corrosion of nails in contact with treated wood, and ability to protect wood from mold growth.  相似文献   

9.
The transmission and interception of light through the canopy is an important indicator of forest productivity in tropical forest ecosystems, and the amount of light that eventually reaches the forest floor is influenced by its interactions with leaves, branches, fruits, and flowers among many different canopy elements. While most studies of forest canopy light interception focus on leaf area index (LAI), very few studies have examined wood area index (WAI), which may account for a substantial component of light interception in tropical forests. The influence of lianas on the interception of light and their overall contribution to WAI is a potentially important factor, but it is generally overlooked because of its difficulty to assess. In this paper we evaluate the relative contribution that lianas have to the overall WAI and canopy openness as function of successional stage via a latitudinal comparison of sites across the Americas (Mexico, Costa Rica and Brazil). Our results suggest that lianas significantly increase WAI and decreases canopy openness. However, lianas were absent at all of our study sites where canopy openness exceeded 60%. Our data are the first to explicitly document the role of lianas in the estimation of WAI and, overall, they will contribute to better estimations of ecosystem level LAI in tropical environments, where there is a lack of data on WAI.  相似文献   

10.
11.
Thirty isolates of Armillaria heimii from western, eastern and southern Africa were cultured for fruit body production in the laboratory. Most isolates fruited easily. Investigation of single-spore progenies revealed that all the isolates do not have the same sexual behaviour: some are heterothallic and unifactorial while others are homothallic. Two African isolates belonging to the species Armillaria mellea also appeared homothallic. Unifactorial heterothallism has not previously been described in Armillaria, species. Homothallic behaviour has been reported only in a rare European species Armillaria ectypa and in the Japanese subspecies Armillaria mellea ssp. nipponica.  相似文献   

12.
13.
Two threatened dipterocarp species,Dipterocarpus costatus and Dipterocarpus alatus are well-known endangered species in lowland forests of southeastern Vietnam,primarily from habitat loss and over-exploitation of their wood.To develop conservation strategies for these species,we analyzed 242 samples using nine microsatellite markers to determine the genetic variability within and among five populations of D.alatus and three of D.costatus,representing the natural range of dipterocarps in Southeast Vietnam.Results indicated low levels of genetic variability within populations with an average gene diversity of 0.223 for D.alatus and 0.152 for D.costatus.Results of bottleneck tests indicated a reduction in population size of both species(P>0.05).Genetic differentiation among populations was high(FST=0.347 for D.costatus and 0.274 for D.alatus),indicating limited gene flow(Nm=0.662 for D.costatus and 0.47 for D.alatus)and isolated populations related to geographical distances.Analysis of molecular variance showed high genetic variation within populations(72.92%for D.alatus and 60.81%for D.costatus)compared to among populations.Bayesian analysis and UPGMA tree also indicated the two optimal genetic clusters related to geographical distances.These results will provide a platform for the conservation,management and restoration of these species.  相似文献   

14.

Efficient forest management, and wood production in particular, requires a forest road network of appropriate density and bearing capacity. The road network affects the choice of a suitable extraction method and the length of the transport route from the forest, while the road standard defines the truck type that can be used.

We evaluate the forest road network’s economic suitability for harvesting operations in the entire Swiss forest, an area of about 13,000 km2 covering a range of topographies, based on the Swiss National Forest Inventory’s (NFI) forest road dataset. This dataset is based on information from an interview survey with the local forest services and includes all forest roads in Switzerland capable of carrying trucks. Extraction options and hauling routes are analysed together; thus, the entire logging process is examined.

Model results include maps of the most suitable extraction method; extraction costs; hauling costs; and a suitability map based on a combination of the results. While the larger part of the Swiss forest is classified as “suitable” for economic harvesting operations, significant portions also fall into the “limited suitability” and “not suitable” categories. Our analysis provides an objective, country-wide, spatially explicit assessment of timber accessibility. The resulting suitability map helps identify areas where timber harvesting is economic using the current forest road network, and where it is not. The model results can be used in road network planning and management, for example, by comparing road-network re-design scenarios, and compared to the spatial distribution of available wood volume.

  相似文献   

15.
To investigate micropores and mesopores in the cell walls of dry wood, CO2 gas and N2 gas adsorption onto dry wood were measured at ice-water temperature (273 K) and liquid nitrogen temperature (77 K). CO2 gas adsorption isotherms obtained were used for determining micropore volumes smaller than 0.6 nm by the HK method (Horvath-Kawazoe method), and N2 gas adsorption isotherms obtained were used for determining the mesopore volume between 2 nm and 50 nm by the Barrett-Joyner-Halenda (BJH) method. Micropores and mesopores existed in cell walls of dry wood, and the cumulative pore volume was much larger for micropores than for mesopores. Micropores in the cell wall of dry wood decreased with elevating heat treatment temperature, and the decreased micropore was reproducible by wetting and drying. Mesopores did not decrease so much with elevating heat treatment temperature. Micropore volumes for the softwood Hinoki and the hardwood Buna were compared. A larger amount of micropores existed in hardwood Buna than in softwood Hinoki, and this relationship was considered to correspond to the difference in thermal softening properties for lignin in water-swollen Hinoki and Buna. This result probably indicates that micropores in the cell walls of dry wood relate to the structure of lignin.  相似文献   

16.
The absolute configuration of bisabolanoids isolated from Yaku-sugi wood were compared with those of dihydrocarvone and dihydrocarveol isomers based on their13C nuclear magnetic resonance data and optical rotations.  相似文献   

17.
柳树DNA提取改良方法研究   总被引:1,自引:0,他引:1  
高质量的DNA是进行林木分子生物学研究的基础与关键。该研究利用改良的CTAB法提取垂柳基因组DNA,并与常规CTAB法、CTAB-硅珠裂解法、SDS法和试剂盒法进行了比较。琼脂糖凝胶电泳检测显示,改良CTAB法提取的DNA浓度和纯度较高,质量优于其他4种提取方法。同时利用改良CTAB法提取了柳树16个自然种及杂交种基因组DNA,并经SSR-PCR扩增反应验证,表明改良CTAB法可作为一种柳树基因组DNA提取的通用方法。  相似文献   

18.
To investigate the influence of heating and drying history on the microstructure of dry wood, in addition to the dynamic viscoelastic properties, CO2 adsorption onto dry wood at ice.water temperature (273 K) was measured, and the micropore size distribution was obtained using the Horvath-Kawazoe (HK) method. Micropores smaller than 0.6 nm exist in the microstructures of dry wood, and they decreased with elevating out-gassing temperature and increased again after rewetting and drying. Dry wood subjected to higher temperatures showed larger dynamic elastic modulus (E′) and smaller loss modulus (E″). This is interpreted as the result of the modification at higher temperature of the instability caused by drying. Drying history influenced the number of micropores smaller than 0.6 nm in dry wood not subjected to high temperature, although the difference in the number of micropores resulting from the drying history decreased with increasing out-gassing temperature. A larger number of micropores smaller than 0.6 nm exist in the microstructure of dry wood in more unstable states, corresponding to smaller E′ and larger E″ than in the stable state. Consequently, unstable states are considered to result from the existence of temporary micropores in the microstructures of dry wood, probably in lignin. Part of this report was presented at the 55th Annual Meeting of the Japan Wood Research Society, Kyoto, March 2005, and at the 56th Annual Meeting of the Japan Wood Research Society, Akita, August 2006  相似文献   

19.
Fireplaysanimportantroleinmakingmancivilization,butfirealsobringaboutdisastertoman.Somedevelopedcountriesdatashowedthatl%ofthegrossnationalproductisdevotedbyconflagrationseveryyear.Inrecentyears,firesoccurredabout3-4hundredtimeseveryyearinChina,di-recteconomiclosswas2Oo-3OOmillionChineseyuanL13,andmostfireswerecausedbywoodburning.Therefore,flameretardanttreatmentforwoodtodiminishorpreventfiredisasterisamosteffectivemeasureofstrategy.Forthisreason,thisresearchfieldhasbeenreceivingagreatat-tC…  相似文献   

20.
Abstract

The objective of this work was to evaluate the performance of particleboard manufactured from roselle (Hibiscus sabdariffa) stalks and eucalyptus (Eucalyptus camaldulensis) wood. The manufacturing parameters were various roselle (Hibiscus sabdariffa) ratios in the mixture (0, 25, 50, 75 and 100%) and press time (3, 5 and 7 min). Modulus of elasticity (MOE), modulus of rupture (MOR), internal bonding (IB) strength values and thickness swelling (TS) after 24-hour water soaking of the panels were determined according to the procedure of European Union (EN) Standard. The results of the study demonstrate that roselle stalks can be an alternative raw material source for particleboard industry. With an increase of roselle particles from 0% to 100%, the TS was reduced, and the IB, MOR and MOE were increased. The highest MOE, MOR, IB strength and TS values of the samples were found as 2754.18, 16.81, 0.89 N/mm2 and 15.26% for the panels made using 100% roselle with a 7-min press time, respectively.  相似文献   

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