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Tin-based metal bath heat treatment: an efficient and recyclable green approach for Pinus massoniana wood modification

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Journal of forestry Research 2018年第6期29卷 1807-1814页

Pinus massoniana L. was thermally treated with low melting point alloy as heating medium to investigate the strength properties changes. Contact angle, color and scanning electron microscopy were recorded to assess the effectiveness of the treatment. Samples were pre-treated in a micro-wave for 5 min followed by metal bath heat treatment at 150, 180, and 210 °C for 2, 4, and 8 h,respectively. Strength properties of metal bath treated wood were decreased with increase temperature and ***, modulus of rupture, impact bending, modulus of elasticity were reduced for all treatments. Maximum compressive strength slightly increased at 150 °C for 4 h followed by gradual reduction. The Janka hardness was reduced in the tangential and radial directions. Treatment of the wood at 210 °C for 8 h caused the wood to become brittle and rupture. The contact angle was considerably higher after thermal treatment. The color of the wood became darker with increasing temperature of thermal treatment. Micrographs of the heat-treated samples showed damage to the cell wall with increase in temperature. Metal bath heat treatment of wood was carried out successfully and some strength properties were reduced.

关键词： Metal bath heat treatment Strength properties Pinus massoniana Color Contact angle

Characterization of mean stem density,fibre length and lignin from two Acacia species and their hybrid

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Journal of forestry Research 2018年第2期29卷 540-546页

作者： Asif Javed Muhammad Seong Siang Ong Wickneswari Ratnam School of environmental and Natural Resource Sciences Faculty of Science and TechnologyUniversiti Kebangsaan Department of forestry and Range management University of Agriculture Faisalabad

The objective of this study was to compare the wood properties related to wood pulp quality of two widely planted Acacia species *** mangium *** Acacia auriculiformis *** *** their *** insoluble lignin content(Klason),mean stem density and fibre length differed considerably among the species and *** possessed a high percent of lignin content compared to *** and the Acacia ***,mean stem density of *** was higher than *** and the *** length of heartwood tissues was generally shorter than that of sapwood *** hybrid had longer fibres than the parent *** was negatively correlated with mean stem ***,the wood properties of the hybrid were superior to its parent *** significant intraspecific variation observed for wood properties of Acacia species could be used in breeding superior hybrids combining desirable traits of the two *** thedifficulty involved in accurately measuring the lignin content compared to mean stem density,selection for plants with low lignin content can be achieved by indirect selection of high mean stem density.

关键词： Acacia mangium × Acacia auriculiformis hybrid Fibre length Indirect selection Lignin content Mean stem density

Assessment of biomass and net primary productivity of a dry tropical forest using geospatial technology

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Journal of forestry Research 2019年第1期30卷 157-170页

作者： Tarun Kumar Thakur S.L.Swamy Arvind Bijalwan Mammohan J.R.Dobriyal Department of environmental Science Indira Gandhi National Tribal University (IGNTU) Department of forestry Indira Gandhi Agricultural University faculty of Technical forestry Indian Institute of Forest Management Navsari Agriculture University

This study quantifies biomass, aboveground and belowground net productivity, along with additional environmental factors over a 2-3 year period in Barnawapara Sanctuary of Chhattisgarh, India through satellite remotesensing and GIS techniques. Ten sampling quadrates20×20, 5×5 and 1×1 m were randomly laid for overstorey (OS), understorey (US) and ground vegetation(GS), respectively. Girth of trees was measured at breast height and collar diameters of shrubs and herbs at 0.1 m height. Biomass was estimated using allometric regression equations and herb biomass by harvesting. Net primary productivity (NPP) was determined by Ssumming biomass increment and litter crop values. Aspect and slope influenced the vegetation types, biomass and NPP in different forests. Standing biomass and NPP varied from 18.6 to101.5 Mg ha^(-1) and 5.3 to 12.7 Mg ha^(-1) a^(-1), respectively,in different forest types. The highest biomass was found in dense mixed forest, while net production recoded in Teak forests. Both were lowest in degraded mixed forests of different forest types. OS, US and GS contributed 90.4, 8.7and 0.7%, respectively, for the total mean standing biomass in different forests. This study developed spectral models for the estimation of biomass and NPP using Normalized Difference Vegetation Index and other vegetation *** study demonstrated the potential of geospatial tools for estimation of biomass and net productivity of dry tropical forest ecosystem.

关键词： Allometric regression equations Fine root biomass Litter fall LAI NDVI Spectral models

Alternative expressions for stand diameter in complex forests

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Forest Ecosystems 2023年第3期10卷 328-336页

作者： Mark J.Ducey John A.Kershaw Jr. Department of Natural Resources and the Environment University of New HampshireDurhamNHUSA faculty of forestry and environmental management University of New BrunswickFrederictonNBCanada

Quadratic mean diameter is the most frequently reported descriptor of the diameter distribution of *** such,it is often used as an indicator of forest stand structure,developmental stage,and ecological and economic ***,quadratic mean diameter can be heavily influenced by the presence or absence of large numbers of small stems in lower canopy strata,and it is also sensitive to left-truncation of the diameter distribution,making its interpretation across inventories with different protocols ***,we examine three alternative expressions of stand diameter:the arithmetic and quadratic mean diameter of the thickest 100 trees per hectare,and the basal area-weighted mean *** data from the United States Forest Inventory and Analysis program for New York and New England,these alternative expressions showed closer correlation with multiple stand structural variables than did quadratic mean diameter,including merchantable cubic and board foot volume per hectare,aboveground live tree carbon per hectare,and total number of live and dead standing trees greater than 40 cm diameter at breast height per hectare(previously proposed as an index of old-growth structure).Arithmetic and quadratic mean diameter of the thickest 100 trees per hectare showed nearly identical performance,and the strongest correlations across the *** develop closed-form expressions for these variables when the diameter distribution is a Weibull,and illustrate their behavior relative to quadratic mean diameter for that *** the reasons for prevalence of quadratic mean diameter as an indicator remain valid,we suggest that these alternative measures should be more widely reported and analyzed to give a more informative depiction of stand structure and development in complex forests.

关键词： Forest structure Diameter at breast height Weibull distribution

Kinetic and Pyrolysis Characteristics of Balsam Fir Needles

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材料科学与工程（中英文版） 2011年第5期5卷 489-503页

作者： Noorfidza Yub Harun Muhammad T. Afzal faculty of forestry and environmental management （forem） University of New Brunswick Fredericton E3B 5A3 NewBrunswick Canada

Analysis of the changes in forest ecosystem functions,structure and composition in the Black Sea region of Turkey

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Journal of forestry Research 2017年第2期28卷 329-342页

作者： Sedat Keles Idris Durusoy Günay Cakir faculty of forestry Cankin Karatekin University18100 CankinTurkey faculty of forestry Duzce University81620 DuzceTurkey Department of forestry and environmental Science Graduate School of Natural and Applied SciencesGumushane University29100 GumushaneTurkey

We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units in Turkey. To assess these effects over a 25 year period we compiled data from three forest management plans that were made in 1986, 2001 and 2011. Temporal changes in forest ecosystem functions were estimated based on the three pillars of forest sustainability： economics, ecology and socio-culture. We assessed a few indicators such as land-use and forest cover, forest types,tree species, development stage, stand age classes, crown closure, growing stock and its increment, and timber biomass. The results of the case study suggested a shift in forest values away from economic values toward ecological and socio-cultural values over last two planning periods. Forest ecosystem structure improved, due mainly to increasing forest area, decreasing non-forest areas（especially in settlement and agricultural areas）, forestation on forest openings, rehabilitation of degraded forests, conversion of even-aged forests to uneven-aged forests and conversion of coppice forests to high forests with greater growing stock increments. There were also favorable changes in forest management planning approaches.

关键词： ecosystem forests timber stand biomass stock favorable closure rehabilitation Turkey

Spatio-temporal suspended sediment fingerprinting under different land management practices

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International Journal of Sediment Research 2023年第4期38卷 481-493页

作者： Maziar Mohammadi Abdulvahed Khaledi Darvishan Nader Bahramifar Seyed Jalil Alavi Department of Watershed management Engineering Faculty of Natural Resources Tarbiat Modares University Department of Geography University of Zurich Department of environmental Science Faculty of Natural Resources Tarbiat Modares University Department of forestry Faculty of Natural Resources Tarbiat Modares University

Understanding spatio-temporal suspended sediment dynamics is more important in large watersheds due to the decisive role of local source apportionment in sediment transport and yield. The Talar River with a large mountainous watershed in northern Iran, which plays a vital role in water supply for agriculture and drinking, recently has faced quality degradation. The current study explores the relative contribution of suspended sediment sources using geochemical tracers and fingerprinting techniques in high and low flow periods along this river. Soil samples were collected from four major land uses including rangeland, forest, rainfed agriculture, and irrigated agriculture, as well as riverbanks and riparian zones along the main river. Furthermore, suspended sediment was sampled at four sampling points along the main river in two seasons. Land use apportionment in suspended sediment yield was calculated using an unmixing model included in a newly developed package(Finger Pro) in high flow and low flow, separately. The fingerprinting results showed a highly spatio-temporal dynamic for sediment source contribution along the main river in high and low flow periods. Natural land uses(forest and rangeland) in upstream reaches and agricultural land uses and riverbank sources in downstream reaches showed higher contributions to suspended sediment yield. The mean contribution of various land uses for both high and low flow periods indicated substantial contributions from forest(34%-41%) and riverbanks(31%-33%). The significant difference in sediment geochemical properties for the two flow seasons highlights the important role of the prevailing climatic-hydrologic condition on river ***, this issue indicates that sediment source contributions and transfer mechanisms are highly dynamic in Talar River watershed. The current study outcomes provide essential knowledge to create a robust strategy for mitigation of river sediment pollution.

关键词： Land use River water quality Sediment fingerprinting Sustainability Unmixing model

environmental impacts of a large-scale incinerator with mixed MSW of high water content from a LCA perspective

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Journal of environmental Sciences 2015年第4期27卷 173-179页

作者： Ziyang Lou Bernd Bilitewski Nanwen Zhu Xiaoli Chai Bing Li Youcai Zhao School of environmental Science and Engineering Shanghai Jiaotong University Institute for Waste management and Contaminated Sites Treatment TU Dresden Faculty of Forestry Geo and Hydro Sciences State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University

Large-scale incinerators are applied widely as a result of the heavy burden of municipal solid waste（MSW） generated, while strong opposition is arising from the public living nearby. A large-scale working incineration plant of 1500 ton/day was chosen for evaluation using life cycle assessment. It was found that the corresponding human toxicity impacts via soil（HTs）, human toxicity impacts via water（HTw） and human toxicity impacts via air（HTa）categories are 0.213, 2.171, and 0.012 personal equivalents（PE）, and global warming（GW100）and nutrient enrichment（NE） impacts are 0.002 and 0.001 PE per ton of waste burned for this plant. Heavy metals in flue gas, such as Hg and Pb, are the two dominant contributors to the toxicity impact categories, and energy recovery could reduce the GW100 and NE greatly. The corresponding HTs, HTw and HTa decrease to 0.087, 0.911 and 0.008 PE, and GW100 turns into savings of- 0.007 PE due to the increase of the heating value from 3935 to5811 k J/kg, if a trommel screener of 40 mm mesh size is used to pre-separate MSW. MSW sorting and the reduction of water content by physical pressure might be two promising pre-treatment methods to improve the combustion performance, and the application of stricter standards for leachate discharge and the flue gas purification process are two critical factors for improvement of the environmental profile identified in this work.

关键词： Large scale incinerator Life cycle assessment environmental impact MSW Sorting system China

Land use change modeling through an integrated Multi-Layer Perceptron Neural Network and Markov Chain analysis(case study: Arasbaran region, Iran)

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Journal of forestry Research 2019年第3期30卷 943-957页

作者： Vahid Nasiri Ali.A.Darvishsefat Reza Rafiee Anoushirvan Shirvany Mohammad Avatefi Hemat Department of forestry Faculty of Natural Resources University of TehranKarajIran Department of environmental Science Faculty of Natural ResourcesUniversity of TehranKarajIran

Temporal land use/land cover (LULC) change information provides a variety of applications for informed management of land resources. The aim of this study was to detect and predict LULC changes in the Arasbaran region using an integrated Multi-Layer Perceptron Neural Network and Markov Chain analysis. At the first step, multi-temporal Landsat images (1990, 2002 and 2014) were processed using ancillary data and were classified into seven LULC categories of high density forest, low-density forest, agriculture, grassland, barren land, water and urban area. Next, LULC changes were detected for three time profiles, 1990–2002, 2002–2014 and 1990–2014. A 2014 LULC map of the study area was further simulated (for model performance evaluation) applying 1990 and 2002 map layers. In addition, a collection of spatial variables was also used for modeling LULC change processes as driving forces. The actual and simulated 2014 LULC change maps were cross-tabulated and compared to ensure model simulation success and the results indicated an overall accuracy and kappa coefficient of 97.79% and 0.992, respectively. Having the model properly validated, LULC change was predicted up to the year 2025. The results demonstrated that 992 and 1592 ha of high and lowdensity forests were degraded during 1990–2014,respectively, while 422 ha were added to the extent of residential areas with a growth rate of 17.58 ha per year. The developed model predicted a considerable degradation trend for the forest categories through 2025, accounting for 489 and 531 ha of loss for high and low-density forests, respectively. By way of contrast, residential area and farmland categories will increase up to 211 and 427 ha, respectively. The integrated prediction model and customary area data can be used for practical management efforts by simulating vegetation dynamics and future LULC change trajectories.

关键词： Satellite images Land use changes Land change modeler Artificial neural network Prediction