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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

Tree allometry responses to competition and complementarity in mixed-species plantations of Betula alnoides

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Forest Ecosystems 2024年第4期11卷 469-479页

作者： Boyao Chen Kaili Liu Chunsheng Wang Junjie Guo Junkun Lu Lin Chen Zhigang Zhao Jie Zeng Research Institute of tropical forestry Chinese Academy of ForestryGuangzhou510520China Central South University of forestry&Technology Changsha410004China experimental center of tropical forestry Chinese Academy of ForestryPingxiang532600China Nanjing forestry University Nanjing210037China

Tree allometry plays a crucial role in tree survival,stability,and timber quantity and quality of mixed-species ***,the responses of tree allometry to resource utilisation within the framework of interspecific competition and complementarity remain poorly *** into consideration strong-and weakspace competition(SC and WC),as well as N_(2)-fixing and non-N_(2)-fixing tree species(FN and nFN),a mixedspecies planting trial was conducted for Betula alnoides,a pioneer tree species,which was separately mixed with Acacia melanoxylon(SC+FN),Erythrophleum fordii(WC+FN),Eucalyptus cloeziana(SC+nFN)and Pinus kesiya ***(WC+nFN)in southern *** years after planting,tree growth,total nitrogen(N)and carbon(C)contents,and the natural abundances of^(15)N and^(13)C in the leaves were measured for each species,and the mycorrhizal colonisation rates of *** were investigated under each *** variations and their relationships with space competition and nutrient-related factors were *** results showed a consistent effect of space competition on the height-diameter relationship of *** in mixtures with FN or *** tree height growth of *** was significantly promoted under high space competition,and growth in diameter at breast height(DBH),tree height and crown size were all expedited in mixtures with *** symbiotic relationship between ectomycorrhizal fungi and *** was significantly influenced by both space competition and N_(2) fixation by the accompanying tree species,whereas such significant effects were absent for arbuscular mycorrhizal ***,high space competition significantly decreased the water use efficiency(WUE)of ***,and its N use efficiency(NUE)was much lower in the FN *** equation modeling further demonstrated that the stem allometry of *** was affected by its NUE and WUE via changes in its height growth,and crown allometry was influ

关键词： Allometric relationship Resources competition and complementarity Mixed-species forest Tree-fungal symbiotic relationship N_2-fixing tree species Resource utilisation strategies

Heartwood variations in mid-aged plantations of Erythrophleum fordii

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Journal of forestry Research 2021年第6期32卷 2375-2383页

作者： Zhigang Zhao Wei Shen Chunsheng Wang Hongyan Jia Jie Zeng Research Institute of tropical forestry Chinese Academy of ForestryLongdongGuangzhou 510520People’s Republic of China Zhaoqing University Zhaoqing City 526061People’s Republic of China experimental Centre of tropical forestry Chinese Academy of ForestryPingxiang City 532600People’s Republic of China

Erythrophleum fordii Oliv.(Caesalpiniaceae)is a rosewood species naturally distributed in southeast Asia and south China,and the heartwood is commonly used for high-quality crafts and *** there are differences in heartwood development among single trees with distinct social status,the relationship between heartwood development and growth performance remains *** information is essential to improve plantation management for high-yield heartwood *** dominant,intermediate and suppressed trees were sampled from *** plantations aged in 32-35 years in Pingxiang City,Guangxi,*** analysis was carried out to determine horizontal and vertical variations of heartwood and *** of annual rings,diameter and area of heartwood and sapwood as well as ratios of heartwood diameter and area at breast height were all significantly influenced by the social status of trees in stands(P<0.05).In these mid-aged plantations,*** stems developed heartwood once the xylem diameter reached 5-10 cm,and then heartwood diameter and area increased with increasing xylem *** ring numbers,diameter and area as well as their ratios decreased with increasing height,while sapwood ring numbers and diameter were relatively constant within the section where heartwood *** and sapwood diameters were equal at heights of approximately 6-m for dominant,5-m for intermediate and 3-m for suppressed *** trees differed considerably from intermediate and suppressed trees in heartwood volume,while heartwood volume ratios were all below 30%,and near 90%in the stem section below 8-m height regardless of social *** analysis showed that DBH was the most important factor influencing heartwood in even-aged *** findings provide evidence for crop tree selection,thinning regimes and reasonable management of plantations of ***.

关键词： Erythrophleum fordii Heartwood formation Spatial variation Tree differentiation

Divergent allocations of nonstructural carbohydrates shape growth response to rainfall reduction in two subtropical plantations

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Forest Ecosystems 2022年第2期9卷 222-233页

作者： Xinwei Guo Shirong Liu Hui Wang Zhicheng Chen Jinglei Zhang Lin Chen Xiuqing Nie Lu Zheng Daoxiong Cai Hongyan Jia Baoliang Niu Key Laboratory of Forest Ecology and Environment of National forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing100091China experimental center of tropical forestry Chinese Academy of ForestryPingxiang532600China Youyiguan Forest Ecosystem Research Station Pingxiang532600China

Nonstructural carbohydrates(NSC)are indicators of tree carbon balance and play an important role in regulating plant growth and ***,our understanding of the mechanism underlying drought-induced response of NSC reserves remains ***,we conducted a long-term throughfall exclusion(TFE)experiment to investigate the seasonal responses of NSC reserves to manipulative drought in two contrasting tree species(a broadleaved tree Castanopsis hystrix *** a coniferous tree Pinus massoniana Lamb.)of the subtropical *** found that in the dry season,the two tree species differed in their responses of NSC reserves to TFE at either the whole-tree level or by organs,with significantly depleted total NSC reserves in roots in both *** the TFE treatment,there were significant increases in the NSC pools of leaves and branches in ***,which were accompanied by significant decreases in fine root biomass and radial growth without significant changes in canopy photosynthesis;while *** exhibited significant increase in fine root biomass without significant changes in radial *** results suggested that under prolonged water limitation,NSC usage for growth in *** is somewhat impaired,such that the TFE treatment resulted in NSC accumulation in aboveground organs(leaf and branch);whereas *** is capable of efficiently utilizing NSC reserves to maintain its growth under drought *** findings revealed divergent NSC allocations under experimental drought between the two contrasting tree species,which are important for better understanding the differential impacts of climate change on varying forest trees and plantation types in subtropical China.

关键词： Photosynthesis Carbon balance Tree growth Nonstructural carbohydrates Carbon limitation

Growth and Transcriptomics Analysis ofMichelia macclurei Dandy Plantlets with Different LED Quality Treatments

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Phyton-International Journal of experimental Botany 2023年第10期92卷 2891-2906页

作者： Zhaoli Chen Ying Liu Bingshan Zeng Qingbin Jiang Shengkun Wang Xiangyang Li Research Institute of tropical forestry Chinese Academy of ForestryGuangzhou510520China

Michelia macclurei Dandy is a significant tree species that has extensive cultivation for forestry and horticulture purposes in southern China,owing to its economic and practical *** quality influences plantlet growth and development during tissue ***,the growth characteristic and molecular regulation of *** under different light quality conditions are not well understood *** this study,we investigated the morphological,chlorophyll content,and transcriptomic responses of *** plantlets under different light-emitting diode(LED)qualities,including white,blue,and red *** results showed that blue light significantly increased plant height(21.29%)and leaf number(18.65%),while red light decreased plant height and leaf number by 7.53%and 16.49%,*** addition,the plantlets’chlorophyll content and etiolation rate were significantly reduced by blue and red light quality compared to white *** to white light,blue light had a negative effect,leading to decreased rooting rate(64.28%),root number(72.72%),and root length(75.86%).Conversely,red light had a positive effect,resulting in increased rooting rate(24.99%),root number(109.58%),and root length(72.72%).Transcriptome analysis identified 54 differentially expressed genes(DEGs)in three groups that consisted of blue light *** light(BL-vs-WL),red light *** light(RL-vs-WL),and red light *** light(RL-vs-BL).Specifically,21,7,and 41 DEGs were identified in the three groups,*** DEGs found in the RL-vs-WL and BL-vs-WL groups were involved in plant hormone signaling,nitrogen metabolism,and phenylpropanoid biosynthesis pathways,which suggests that *** plantlets adapt to the changes of light quality via modulating gene ***,our study provides valuable insights for understanding the molecular and morphological responses of *** plantlets under different light qualities.

关键词： Michelia macclurei plantlets growth characteristics transcriptome

Modelling growing space of four valuable broadleaved tree species in southern China

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forestry Studies in China 2013年第3期15卷 167-178页

作者： Johanna SCHULER Josephine CUENI Heinrich SPIECKER Wen-Fu GUO Faculty of Environment and Natural Resources Albert-Ludwigs-Universitt Sci-Tech Division of the experimental Centre for tropical forestry Chinese Academy of Forestry

We present management tools for growing four valuable broadleaved tree species, indigenous to *** southern China. Crown diameter （CD） of the species studied can be predicted very well by using a model that is so e y a near funct on of d ameter at breast he ght （DBH）. The add t on of tree age （AGE） and yield class （YC） to this-nodel did not significantly improve its predictive capacity. We used species-specific crown diameter models to calcu- ate the amount of growing space and subsequently stand density that each species needs to achieve desired stem ＂adial growth rates. Furthermore we used this information to calculate a ＂distance factor＂, a rule of thumb that roughly ~stimates the distance between two neighboring trees needed to achieve a desired future target diameter. These tools ＇acilitate the planning of thinning regimes by using crown diameter models combined with annual radial growth rates to ;alculate the number of crop trees per hectare required to reach a desired target stem diameter.

关键词： crown diameter diameter growth growth model valuable timber management tool

Enhancement of modulation depth of an all-optical switch using an azo dye-ethyl red film

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Chinese Physics B 2010年第8期19卷 429-436页

作者：陆文强陈桂英郝召锋许京军田建国张春平 Physics experimental Teaching center School of PhysicsNankai University Key Laboratory of tropical Marine Environmental Dynamics South China Sea Institute of OceanologyChinese Academy of Sciences Photonic center School of PhysicsNankai Universitv

The polymethyl methacrylate （PMMA） film doped with an azo dye ethyl-red （ER） film is employed to demonstrate the properties of an all-optical switch by its photoinduced dichroism and birefringence. We show how to enhance remarkably the modulation depth of all-optical switches almost to 100% by using two linear polarization beams： one beam is inclined at 45° with respect to the probing beam and serves as a pumping beam, and the other beam is perpendicular to the probing beam and used as an erasing beam. Furthermore, a maximum-to-minimum output intensity ratio of 2000：1 is achieved in experiment, which is very useful and important for optical storages and image displays.

关键词： all-optical switch azo dye ethyl-red film modulation depth

Amino acid profiles and protein quality of Siberian apricot(Prunus sibirica L.)kernels from Inner Mongolia

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Journal of forestry Research 2020年第4期31卷 1391-1397页

作者： Mingyu Yin Tana Wuyun Zhongmao Jiang Jie Zeng State Key Laboratory of Tree Genetics and Breeding Nontimber Forestry Research and Development CenterPaulownia Research and Development Center of ChinaState Forestry AdministrationKey Laboratory of Non-timber Forest Germplasm Enhancement and Utilization of State Forestry AdministrationChinese Academy of ForestryZhengzhou 450003HenanPeople’s Republic of China Research Institute of tropical forestry Chinese Academy of ForestryGuangzhou 510520GuangdongPeople’s Republic of China

Siberian apricot(Prunus sibirica L.)is a traditional nut tree species in East Asia and Siberia and is a possible contribution to healthy ***,it has attracted little research attention and information on the nutritional value of its kernel is *** this study,the profile,nutritional value and variation of amino acids were investigated in eight *** kernels contained29×10-2 g/g protein and were rich in glutamic acid(26.5%),aspartic acid(11.3%)and arginine(10.1%).They showed higher essential amino acids(EAA)than similar protein values for *** variation coefficients of amino acids ranged from 3.8 to 43.7%,and the levels of seven amino acids were significantly different among the eight *** proportion of essential amino acids to total amino acids and amino acid score were also quite *** was negatively correlated with some amino acids and protein quality *** conclusion,there were two superior provenances(Wanjiagou and Horinger County)with high EAA contents and protein quality,and could be used in the large-scale development of this species.

关键词： Prunus sibirica L. Amino acids Nutritional value Diversity

Impacts of climate change and human activities on vegetation dynamics on the Mongolian Plateau, East Asia from 2000 to 2023

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Journal of Arid Land 2024年第8期16卷 1062-1079页

作者： YAN Yujie CHENG Yiben XIN Zhiming ZHOU Junyu ZHOU Mengyao WANG Xiaoyu School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China experimental center of Desert forestry Chinese Academy of ForestryDengkou 015200China Inner Mongolia Dengkou Desert Ecosystem National Observation Research Station National Forestry and Grassland AdministrationDengkou 015200China

The Mongolian Plateau in East Asia is one of the largest contingent arid and semi-arid areas of the *** the impacts of climate change and human activities,desertification is becoming increasingly severe on the Mongolian *** the vegetation dynamics in this region can better characterize its ecological *** this study,based on Moderate Resolution Imaging Spectroradiometer(MODIS)images,we calculated the kernel normalized difference vegetation index(kNDVI)on the Mongolian Plateau from 2000 to 2023,and analyzed the changes in kNDVI using the Theil-Sen median trend analysis and Mann-Kendall significance *** further investigated the impact of climate change on kNDVI change using partial correlation analysis and composite correlation analysis,and quantified the effects of climate change and human activities on kNDVI change by residual *** results showed that kNDVI on the Mongolian Plateau was increasing overall,and the vegetation recovery area in the southern region was significantly larger than that in the northern *** 50.99%of the plateau showed dominant climate-driven effects of temperature,precipitation,and wind speed on kNDVI *** analysis showed that climate change and human activities together contributed to 94.79%of the areas with vegetation *** human activities promoted the recovery of local vegetation,and climate change inhibited vegetation growth in the northern part of the Mongolian *** study provides scientific data for understanding the regional ecological environment status and future changes and developing effective ecological protection measures on the Mongolian Plateau.

关键词： kernel normalized difference vegetation index(kNDVI) human activities climate change partial correlation analysis composite correlation analysis residual analysis Mongolian Plateau