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Growth and mineral nutrient analysis of teak (Tectona grandis) grown on acidic soils in south China

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Journal of forestry Research 2017年第3期28卷 503-511页

作者： Zaizhi Zhou Shichao Liu Kunnan Liang Huaming Ma Guihua Huang Research Institute of tropical forestry Chinese Academy of Forestry

Teak （Tectona grandis L.f.） is widely planted in the world due to its high market demand, economic, ecological and social value. Its plantations have mostly been established and expanded into sites that are acidic to severely acidic in southern China. But, there are no available and specific evidence-based nutrient management techniques. To better recognize and understand the relationship between teak tree growth and nutrient content in the foliage and soil and establish nutrient norms are critical to optimally manage these young plantations. We studied the foliar nutrient and soil chemistry in 19 representative teak plantations aged 5-8 years. Regression analysis indicated that the mean annual increment of teak volume was linearly and positively correlated with foliar N, Ca, Fe and B concentrations, with soil base saturation percentage, available P and Zn concentrations, and negatively correlated with soil Al concentration. Only if the Ca and Mg contents in soil were enhanced, could the increase in soil base saturation percentage benefit teak growth. A revised classification of low-and high-yielding stands was established by using a sorting method of principal components over 6 foliar macro and 8 micro elements in a Diagnosis and Recommendation Integrated System （DRIS）. Specific DRIS norms for teak plantations in acid soils were derived. The nutrient balance of N, P, K Ca, Mg, Zn, B with Fe or A1, Ca with Mg, and Fe with AI provided a key to promote the growth of teak in acid soils. Meanwhile, soil Zn was also found as a primary trace element that affected teak growth in this study.

关键词： Acid soils DRIS diagnosis and norm Mineral nutrient relationship Plant mineral nutrition Soil properties Teak

Genetic variation in growth traits and stem–branch characteristics and their relationships to Eucalyptus clones

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Journal of forestry Research 2015年第4期26卷 957-962页

作者： Shijun Wu Zhaohua Lu Jianmin Xu Guangchao Chen Yingan Zhu Guangyou Li Research Institute of tropical forestry Chinese Academy of Forestry

Eucalyptus has become an important genus in China because it displays adaptability to a wide range of site conditions and produces pulp wood and veneer on short rotations. The aim of this study was to estimate genetic parameters and relationships and consider impli- cations for development of clonal forestry. We assessed growth traits, stem-branch characteristics, crown diameter and height of fresh branch for 20 Eucalyptus hybrid clones in China measured at the age of 44 months. Analysis of variance showed that there were significant differences in growth traits, height of fresh branch and stem straightness among clones. Significant differences in height, volume, crown diameter, height of fresh branch and branch size among replicates were also recorded. Coefficients of vari- ation ranged from 9.84 to 28.54 % for growth traits, 12.03 to 17.25 % for stem-branch characteristics, 18.26 % for crown diameter and 11.73 % for height of fresh branch. Estimates of repeatabilities for height, diameter at breastheight over bark, volume, crown diameter, height of fresh branch, stem straightness and branch size at clone mean level were 0.86, 0.80, 0.80, 0.54, 0.85, 0.77 and 0.44 respectively. Diameter at breast height over bark and height had strongly positive phenotypic and genotypic correlations with volume, ranging from 0.96 to 1.00. The positive genotypic and phenotypic correlations between growth traits and other studied traits suggested that fast growing clones always had bigger crown diameter, higher height of fresh branch, straighter stems and relatively smaller branches.

关键词： Multiple comparison Clonal variation Genotypic and phenotypic correlations Eucalyptus clones

Growth and nutrient dynamics of Betula alnoides seedlings under exponential fertilization

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Journal of forestry Research 2018年第1期29卷 111-119页

作者： Lin Chen Chunsheng Wang Bernard Dell Zhigang Zhao Junjie Guo Daping Xu Jie Zeng The Experimental Center of tropical forestry Chinese Academy of Forestry Research Institute of tropical forestry Chinese Academy of Forestry Division of Research and Development Murdoch University

Betula alnoides is a fast-growing hardwood species grown in large plantations in Southeast Asia and South *** requirements for producing robus seedlings,growth and nutrient dynamics were investigated using exponential fertilization *** collar diameter,height,dry mass and nutrient contents of seedlings increased exponentially in all fertilization treatments as time ***,with water soluble fertilizer（Plant Products plus microelements N–P2O5–K2O：20–20–20）,300 mg N seedling-1was *** analysis revealed that P was the most responsive nutrient element followed by N and *** of N and K were evident in the plants without N addition,which induced initial P sufficiency and then luxury consumption probably due to the antagonistic interaction between N and *** deficiencies of N,P and K were mostly observed in al exponential regimes during the experiment because seedling growth rate exceeded nutrient uptake rate,inferring that further study on improving the nutrient uptake efficiency is *** of relationships among nutrient supply,dry mass,N content and N concentration demonstrated that 100–400 mg N seedling-1induced sufficiency to luxury consumption of nitrogen without significant change in dry mass,and 400 mg N seedling-1is recommended to apply for nutrient loading of seedlings before *** findings will help improve seedling quality and enhance the production of robust seedlings for plantation forestry of this species.

关键词： Betula alnoides Growth performance Luxury nutrient consumption Nitrogen requirement Vector analysis

Investigation of physico-chemical properties and microbial community during poultry manure co-composting process

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Journal of Environmental Sciences 2015年第2期27卷 81-94页

作者： Omar Farah Nadia Loo Yu Xiang Lee Yei Lie Dzulkornain Chairil Anuar Mohammed P.Mohd Afandi Samsu Azhari Baharuddin Department of Process and Food Engineering Faculty of Engineering Universiti Putra Malaysia Institute of tropical forestry and forestry Products (INTROP) Putra Infoport Universiti Putra Malaysia

Co-composting of poultry manure and rubber wood sawdust was performed with the ratio of 2：1（V/V） for a period of 60 days. An investigation was carried out to study the extracellular enzymatic activities and structural degradation utilizing Fourier transform infrared spectroscopy（FT-IR）, thermogravimetry and differential thermal analysis（TG/DTA）and scanning electron microscopy（SEM）. The microbial succession was also determined by using denaturing gel gradient electrophoresis（DGGE）. The compost was able to reach its highest temperature of 71°C at day 3 and stabilized between 30 and 40°C for 8 ***, FPase and β-glucosidase acted synergistically in order to degrade the cellulosic substrate. The xylanase activities increased gradually during the composting and reached the peak value of 11.637 U/g on day 35, followed by a sharp decline. Both Li P and Mn P activities reached their peak values on day 35 with 0.431 and 0.132 U/g respectively. The FT-IR spectra revealed an increase in aromaticity and a decrease in aliphatic compounds such as carbohydrates as decomposition proceeded. TGA/DTG data exhibited significant changes in weight loss in compost samples, indicating degradation of organic matter. SEM micrographs showed higher amounts of parenchyma exposed on the surface of rubber wood sawdust at day 60, showing significant degradation. DGGE and 16 S r DNA analyses showed that Burkholderia sp., Pandoraea sp., and Pseudomonas sp. were present throughout the composting process. Ornithinibacillus sp. and Castellaniella ginsengisoli were only found in the initial stage of the composting, while different strains of Burkholderia sp. also occurred in the later stage of composting.

关键词： Composting Poultry manure Cellulose Denaturing gel gradient electrophoresis Microbial community

Morphometric study confirms the presence of only Vatica mangachapoi on Hainan Island, China

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Journal of forestry Research 2018年第3期29卷 636-643页

作者： Junjie Guo Shuaibin Shang Jie Zeng Research Institute of tropical forestry CAF

To date only one species of the genus Vatica Linn.(Dipterocarpaceae) has been identified, and a subspecies and three varieties have been reported on Hainan Island, China. However, it remained controversial whether the species was Vatica mangachapoi or a new species Vatica hainanensis, and whether the subspecies or varieties are taxonomically valid. We evaluated here morphometric variations of 133 trees collected from nine populations and herbarium specimens of Vatica spp. using 16 traits of leaf and fruit. Among these, leaf traits varied more within and among populations than did fruit traits. Four traits of ratios were more stable than directly-measured traits within and among populations. The ranges of lamina length, lamina width and height of maximum lamina width point were the greatest among the 16 traits, while number of lateral veins varied least among the 12 directly-measured traits. Measurements from all 9 populations overlapped for each morphological trait, and variation of each trait was continuous among both individuals and populations. The range of variation did not distinguish any specimen from V mangachapoi as described in the flora of Southeast Asia By cluster analysis, individuals of each population as wel as specimens of each variety formed no distinct clusters The published varieties thus were characterized by no distinguishing variations in comparison with the nine sampled populations. In conclusion, the new species V hainanensis as well as the subspecies and varieties were not supported by our comparisons, and only V. man gachapoi without any subspecies or varieties occurs on Hainan Island, China.

关键词： Vatica Linn. Vatica mangachapoi Morphological variability Cluster analysis Hainan Island

Effect of slope position on leaf and fine root C,N and P stoichiometry and rhizosphere soil properties in Tectona grandis plantations

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Journal of forestry Research 2023年第6期34卷 1997-2009页

作者： Qingqing Zhang Zaizhi Zhou Weiwei Zhao Guihua Huang Gaofeng Liu Xiaofei Li Junduo Wu Research Institute of tropical forestry Chinese Academy of ForestryGuangzhou 510520People’s Republic of China Experimental Center of tropical forestry Chinese Academy of ForestryPingxiang 532600People’s Republic of China

Little is known about C-N-P stoichiometries and content in teak(Tectona grandis)plantations in South China,which are mostly sited on hilly areas with lateritic soil,and the effect of slope position on the accumulation of these elements in trees and rhizosphere *** we analyzed the C,N,P content and stoichiometry in leaves,fine roots and rhizosphere soils of trees on the upper and lower slopes of a 12-year-old teak *** Kraft classification system of tree status was used to sample dominant,subdominant and mean trees at each slope *** results showed that the C,N and P contents in leaves were higher than in fine roots and rhizosphere *** lowest C/N,C/P and N/P ratios were found in rhizosphere soils,and the C/N and C/P ratios in fine roots were higher than in *** accumulation in leaves,fine roots and rhizosphere soils were significantly influenced by slope position and tree class with their interaction mainly showing a greater effect on rhizosphere *** C content and C/N ratio,fine root C and P contents,and C/N and C/P ratios all increased distinctly with declining slope *** contents of organic matter(SOM),ammonium(NH4+-N),nitrate-nitrogen(NO3--N)and available potassium(AK)in rhizosphere soils were mainly enriched on upper slopes,but exchange calcium(ECa),available phosphorus(AP),and pH were relatively *** in the C,N and P stoichiometries in trees were mainly attributed to the differences in rhizosphere soil properties.N and P contents showed significant positive linear relationships between leaf and rhizosphere soil,and C content negative linear correlation among leaves,fine roots and rhizosphere *** properties of rhizosphere soils,particularly C/N and NH4+-N,had significant effects on the leaf nutrients in trees on the upper ***,rhizosphere soil properties mainly influenced fine root nutrients on the lower slope,and soil AK was the major influencing ***,these

关键词： Tectona grandis Stoichiometric ratio Rhizosphere soil Dominant trees Nutrient accumulation

Simulating the heartwood formation process of Erythrophleum fordii in South China

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Journal of forestry Research 2015年第4期26卷 1049-1055页

作者： Zhigang Zhao Junjie Guo Chunsheng Wang Jie Zeng Research Institute of tropical forestry CAF

We studied the formation of heartwood in Ery- throphleumfordii Oliv., an endangered rosewood species, by cross-section analysis on 52 stumps aged 28-57 years and arbitrarily sampled from natural forests in South China. Width and area of heartwood were positively correlated with age and xylem width （XW）, and were independent of annual radial growth. The proportions of heartwood and sapwood areas were equal at about 40 years. The heartwood formation pro- cess was simulated by linear regression of age and XW.

关键词： Erythrophleum fordii Growth process Heartwood formation Heartwood width Rosewoodspecies

Exploring the spatiotemporal heterogeneity of vegetation changes in subtropical humid karst region under CO2 fertilization

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Journal of Geographical Sciences 2025年第1期35卷 65-87页

作者： CHEN Meng ZHOU Qiuwen PENG Dawei YAN Weihong School of Geography and Environmental Science Guizhou Normal University Huanjiang Observation and Research Station for Karst Ecosystem Guangxi Key Laboratory of Karst Ecological Processes and Services Institute of Subtropical Agriculture CAS University of Chinese Academy of Sciences faculty of Geographical Science Beijing Normal University forestry Bureau of Shibing County

Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide （CO2） fertilization in hot and humid *** subtropical humid karst region is a hot and humid region;whether and to what extent CO2fertilization affects vegetation changes in such regions remains *** this study,we investigated the degree to which CO2fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression *** showed that CO2fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO2fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau *** studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these *** findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions.

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Recent development and challenges in enhancing fire performance on wood and wood-based composites:A 10-year review from 2012 to 2021

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Journal of Bioresources and Bioproducts 2024年第1期9卷 27-42页

作者： Charles Michael Albert Kang Chiang Liew faculty of tropical forestry Universiti Malaysia SabahKota Kinabalu 88400Kota KinabaluSabah 88400Malaysia

Due to their durability,versatility,and aesthetic value,wood and wood-based composites are widely used as building *** fact that these materials are flammable,however,raises a major worry since they might cause fire hazards and significant loss of life and *** article investigates the variables that affect fire performance as well as the various fire-retardant treatments and their *** current developments and challenges in improving the fire performance of wood and wood-based composites treated with fire-retardant materials are summarized in this ***,organic chemicals,and densification are some recent developments in fire-retardant treatments that are also *** points from the review are summarized,along with potential areas for further research and development.

关键词： Fire performance Fire-retardant materials Wood Wood-based composite Nanoparticles coating Surface charring Bio-based fire retardant Densification