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Estimating and mapping forest biomass in northeast china using joint forest resources inventory and remote sensing data

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Journal of Forestry research 2018年第3期29卷 789-803页

作者： Xinchuang wang Shidong wang limin Dai Henan Polytechnic University Jiaozuo 454000People’s Republic of China State Key laboratory of Forest and Soil Ecology Institute of Applied EcologyChinese Academy of SciencesShenyang 110164People’s Republic of China

Being able to accurately estimate and map forest biomass at large scales is important for a better understanding of the terrestrial carbon cycle and for improving the effectiveness of forest management. In this study, forest plot sample data, forest resources inventory(FRI) data, and SPOT Vegetation(SPOT-VGT) normalized difference vegetation index(NDVI) data were used to estimate total forest biomass and spatial distribution of forest biomass in northeast china(with 1 km resolution). Total forest biomass at both county and provincial scales was estimated using FRI data of 11 different forest types obtained by sampling 1156 forest plots, and newly-created volume to biomass conversion models. The biomass density at the county scale and SPOT-VGT NDVI data were used to estimate the spatial distribution of forest biomass. The results suggest that the total forest biomass was 2.4 Pg(1 Pg = 10g), with an average of 77.2 Mg ha, during the study period. Forests having greater biomass density were located in the middle mountain ranges in the study area. Human activities affected forest biomass at different elevations, slopes and aspects. The results suggest that the volume to biomass conversion models that could be developed using more plot samples and more detailed forest type classifications would be better suited for the study area and would provide more accurate biomass estimates. Use of both FRI and remote sensing data allowed the down-scaling of regional forest biomass statistics to forest cover pixels to produce a relatively fineresolution biomass map.

关键词： Forest biomass Biomass density Spatial distribution Human disturbance Remote sensing

The Clustering of Zn6Y9 and Its Predominant Role in Long Period Stacking Order Phases in Mg-Zn-Y Alloys: a First-principles Study

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The Clustering of Zn6Y9 and Its Predominant Role in Long Per...

Annealing-induced Grain Refinement in a Nanostructured Ferritic Steel

中国材料大会2012

作者： Shangyi Ma limin liu shaoqing wang shenyang national laboratory for materials science Institute of Metal Research Chinese Academy of Sciences Beijing Computational science research Center Chinese Academy of Engineering Physics Chengdu Green Energy and Green Manufacturing Technology R&D Center

ISBN: (纸本)9783037856093

The local structures of Zn and Y in the long period stacking order （LPSO） phase in Mg-Zn-Y system were investigated by first principles calculations in details. The clustering of Zn and Y atoms ranging from single stacking fault layer to four consecutive layers was explicitly demonstrated. The calculations indicate that Zn and Y atoms prefer clustering in the form of Zn6Y9 embedding in ABCA-type building block to hthe random or ordered arrangements of Zn and Y atoms being enriched in two stacking fault layers. The cluster of Zn6Y9 can be regarded as the ideal stoichiometric component of LPSO and it plays a predominant role in the LPSO phases. The formation of LPSO phases is highly associated with the Zn6Y9 cluster and its derivatives.

关键词： Magnesium alloys Long period stacking order phases First-principles study

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Journal of materials science & Technology 2012年第1期28卷 41-45页

作者： limin wang Zhenbo wang Sheng Guo Ke Lu Sheng Guo and Ke Lu shenyang national laboratory for materials science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China

A nanostructured surface layer with a mean ferrite grain size of -8 nm was produced on a Fe-gCr steel by means of surface mechanical attrition treatment. Upon annealing, ferrite grains coarsen with increasing temperature and their sizes increase to -40 nm at 973 K. Further increasing annealing temperature leads to an obvious reduction of ferrite grain sizes, to -14 nm at 1173 K. The annealing-induced grain refinement is analyzed in terms of phase transformations in the nanostructured steel.

关键词： Nanostructured Surface mechanical attrition treatment (SMAT) Ferritic steel Grain refinement Austenitization

Single-atom Sn-Zn pairs in CuO catalyst promote dimethyldichlorosilane synthesis

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national science Review 2020年第3期7卷 600-608页

作者： Qi Shi Yongjun Ji Wenxin Chen Yongxia Zhu Jing Li Hezhi liu Zhi Li Shubo Tian Ligen wang Ziyi Zhong limin wang Jianmin Ma Yadong Li Fabing Su Gripm Advanced materials Co. Ltd State Key laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of Sciences Zhongke Langfang institute of Process Engineering Beijing Key laboratory of Construction Tailorable Advanced Functional materials and Green Applications School of Materials Science and Engineering Beijing Institute of Technology Department of Chemistry Tsinghua University College of Engineering Guangdong Technion–Israel Institute of Technology (GTIIT) Technion–Israel institute of Technology (IIT) School of Physics and Electronics Hunan University institute of Industrial Chemistry and Energy Technology Shenyang University of Chemical Technology

Single-atom catalysts are of great interest because they can maximize the atom-utilization efficiency and generate unique catalytic properties; however, much attention has been paid to single-site active components, rarely to catalyst promoters. Promoters can significantly affect the activity and selectivity of a catalyst, even at their low concentrations in catalysts. In this work, we designed and synthesized Cu O catalysts with atomically dispersed co-promoters of Sn and Zn. When used as the catalyst in the Rochow reaction for the synthesis of dimethyldichlorosilane, this catalyst exhibited much-enhanced activity,selectivity and stability compared with the conventional Cu O catalysts with promoters in the form of nanoparticles. Density functional theory calculations demonstrate that single-atomic Sn substitution in the Cu O surface can enrich surface Cu vacancies and promote dispersion of Zn to its atomic levels. Sn and Zn single sites as the co-promoters cooperatively generate electronic interaction with the Cu O support, which further facilitates the adsorption of the reactant molecules on the surface, thereby leading to the superior catalytic performance.

关键词： dual single-atom promoters CuO catalyst dimethyldichlorosilane synthesis Rochow reaction catalytic performance

Determining the contribution of Mo single atoms components in MoO_(2)nanocatalyst in transfer hydrogenation

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Nano research 2023年第2期16卷 2302-2310页

作者： Ze-Nan Hu Yongjian Ai Yan Zhao Yiming wang Kelong Ding Wenhui Zhang Rongxiu Guo Xinyue Zhang Xiangbin Cai Ning wang Jianshe Hu Qionglin Liang Hongyang liu Fei Huang limin Wu Jiangwei Zhang Hong-bin Sun School of Environmental Engineering and Chemistry Luoyang Institute of Science and TechnologyLuoyang 471023China Department of Chemistry Northeastern UniversityShenyang 110819China MOE Key laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology Beijing Key Lab of Microanalytical Methods&InstrumentationDepartment of ChemistryCenter for Synthetic and Systems BiologyTsinghua UniversityBeijing 100084China College of Energy Material and Chemistry Inner Mongolia UniversityHohhot 010021China Department of Physics and Center for Quantum materials Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina shenyang national laboratory for materials science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Nanocatalysts are likely to contain undetected single-atom components,which may have been ignored but have significant effect in catalytic ***,we report a catalyst composed of Mo single atoms(SAs)and MoO_(2)nanoparticles(NPs)(MoSAs-MoO_(2)@NC),which is an exact model to understand how the SAs contribute to the *** experimental results and the density functional theory calculations reveal that Mo SAs on nitrogen-doped carbon provides the reaction zone for nitro reduction,while MoO_(2)is the active site for decomposing hydrazine hydrate to produce H*.Thanks to the synergy between Mo SAs and MoO_(2)NPs,this catalyst exhibits noble metal-like catalytic activity(100%conversion at 4 min)for the dechlorination-proof transfer ***,the hydrogen migration on the catalyst is verified by the electrochemical tests in the absence of a hydrogen *** work provides a model for further study on the coexistence of single atoms in nanoparticle catalysts.

关键词： synergistic effect Mo single atoms MoO_(2)nanocatalyst transfer hydrogenation nitroarenes

Carbon Stock of Larch Plantations and Its Comparison with an Old-growth Forest in Northeast china

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chinese Geographical science 2016年第1期26卷 10-21页

作者： QI Guang CHEN Hua ZHOU Li wang Xinchuang ZHOU wangming QI Lin YANG Yuhua YANG Fengling wang Qingli DAI limin State Key laboratory of Forest and Soil Ecology Institute of Applied EcologyChinese Academy of SciencesShenyang 110164China Key laboratory of Ecological Restoration in Hilly Area Pingdingshan UniversityPingdingshan 467000China Department of Biology University of Illinois at SpringfieldSpringfieldIllinois 62703USA Henan Polytechnic University Jiaozuo 454000China

The overall goal of this study was to understand carbon(C) stock dynamics in four different-aged Japanese larch(Larix kaempferi) plantations in Northeast china that were established after clear-cutting old-growth Korean pine deciduous forests. Four Japanese larch plantations which were at 10, 15, 21, and 35 years old and an old-growth Korean pine deciduous forest which was 300 years old in Northeast china were selected and sampled. We compared the C pools of biomass(tree, shrub and herb), litterfall(LF), and soil organic carbon(SOC) among them. The biomass C stock of larch plantation at 10, 15, 21, and 35 years old was 26.8, 37.9, 63.6, and 83.2 Mg/ha, respectively, while the biomass C stock of the old-growth Korean pine deciduous forest was 175.1 Mg/ha. The SOC stock of these larch plantations was 172.1, 169.7, 140.3, and 136.2 Mg/ha respectively, and SOC stock of 170.4 Mg/ha in the control of old-growth forest. The biomass C stock increased with stand age of larch plantations, whereas SOC stock decreased with age, and C stock of LF did not change significantly(P > 0.05). The increase of biomass C offset the decline of SOC stock with age, making total carbon stock(TCS) of larch plantations stable from stand ages of 10–35 years. The TCS in larch plantations was much smaller than that in the old-growth forest, suggesting that the conversion of old-growth forests to young larch plantations releases substantial C into the atmosphere.

关键词： larch plantation old-growth forest biomass carbon soil organic carbon total carbon stocks

Spatiotemporal evidence of tree-growth resilience to climate variations for Yezo spruce(Picea jezoensis var. komarovii) on Changbai Mountain, Northeast china

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Journal of Forestry research 2020年第3期31卷 927-936页

作者： Xuerui Gai Shoule wang Li Zhou Jian Wu wangming Zhou Jianhua Bi Linlin Cao limin Dai Dapao Yu Key laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China University of chinese academy of sciences Beijing 100049People’s Republic of China Xinjiang institute of Ecology and Geography chinese academy of sciences Urumqi 830011People’s Republic of China shenyang University Shenyang 110044People’s Republic of China

Global warming-induced changes in tree-growth resilience to climate variations have been widely reported for mid-and high-latitude regions around the world. Most studies have focused on the spatial variability of trees in radial growth-climate relationships on Changbai Mountain in Northeast china, but little is known about temporal changes in tree growth in response to climate. We explored the stability of effect of climate variables on radial growth of Yezo spruce [Picea jezoensis Carr. var. komarovii(***.) Cheng et ***] at 1200, 1400, and 1600 m above sea level, representing low, middle, and upper ranges of the spruce-fir mixed forest on Changbai Mountain. The results showed that the relation between tree growth and climate did not vary with altitude, but the stability of the tree-growth-climate relationship did vary with altitude as the climate changed. Radial growth of Yezo spruce at allthree elevations was influenced primarily by maximum temperature during May(Tmax5) and mean minimum temperature from January to March(Tmin1-3). More specifically, the relationship strengthened significantly at lower elevations, but weakened significantly at higher elevation, and fluctuated at mid elevations since *** in Tmin1-3 and decrease in Tmax5 were the main reasons for the decrease in the radial growth at three altitudes. The findings of this study clarified that the decrease in radial growth on Changbai Mountain is not a “divergence problem” of an unexpected decrease in tree growth in response to an increase in mean temperature and provides a reference for using tree-ring data to reconstruct climate patterns and/or predict the growth of trees under various climate change scenarios.

关键词： Altitudinal gradient Changbai Mountain Ring width Spatiotemporal stability Yezo spruce

The First High-quality Reference Genome of Sika Deer Provides Insights into High-tannin Adaptation

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Genomics, Proteomics & Bioinformatics 2023年第1期21卷 203-215页

作者： Xiumei Xing Cheng Ai Tianjiao wang Yang Li Huitao liu Pengfei Hu Guiwu wang Huamiao liu Hongliang wang Ranran Zhang Junjun Zheng Xiaobo wang Lei wang Yuxiao Chang Qian Qian Jinghua Yu Lixin Tang Shigang Wu Xiujuan Shao Alun Li Peng Cui Wei Zhan Sheng Zhao Zhichao Wu Xiqun Shao Yimeng Dong Min Rong Yihong Tan Xuezhe Cui Shuzhuo Chang Xingchao Song Tongao Yang limin Sun Yan Ju Pei Zhao Huanhuan Fan Ying liu Xinhui wang Wanyun Yang Min Yang Tao Wei Shanshan Song Jiaping Xu Zhigang Yue Qiqi Liang Chunyi Li Jue Ruan Fuhe Yang Key laboratory of Genetics Breeding and Reproduction of Special Economic AnimalsMinistry of Agriculture and Rural AffairsInstitute of Special Animal and Plant SciencesChinese Academy of Agricultural SciencesChangchun 130112China Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China CAS Key laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Annoroad Gene Technology(Beijing)Co. LtdBeijing 100176China Novogene Bioinformatics institute Beijing 100083China

Sika deer are known to prefer oak leaves,which are rich in tannins and toxic to most mammals;however,the genetic mechanisms underlying their unique ability to adapt to living in the jungle are still *** identifying the mechanism responsible for the tolerance of a highly toxic diet,we have made a major advancement by explaining the genome of sika *** generated the first high-quality,chromosome-level genome assembly of sika deer and measured the correlation between tannin intake and RNA expression in 15 tissues through 180 *** genome analyses showed that the UGT and CYP gene families are functionally involved in the adaptation of sika deer to high-tannin food,especially the expansion of the UGT family 2 subfamily B of UGT *** first chromosome-level assembly and genetic characterization of the tolerance to a highly toxic diet suggest that the sika deer genome may serve as an essential resource for understanding evolutionary events and tannin *** study provides a paradigm of comparative expressive genomics that can be applied to the study of unique biological features in non-model animals.

关键词： Sika deer Whole-genome sequencing Chromosome-scale assembly Oak leaf Tannin tolerance

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我国主要草原有害生物防治指标制定与分析

草业科学 2022年第9期39卷 1773-1781页

作者：岳方正李璇杨鼎王志鹏徐震霆花立民涂雄兵王炳煜韩海斌柴守权国家林业和草原局生物灾害防控中心辽宁沈阳110034 新疆维吾尔自治区蝗虫鼠害预测预报防治中心站新疆乌鲁木齐830000 甘肃农业大学草业学院/国家林业草原高寒草地鼠害防控工程技术研究中心甘肃兰州730070 中国农业科学院植物保护研究所植物病虫害生物学国家重点实验室北京100193 中国农业科学院草原研究所内蒙古呼和浩特010010

草原啮齿动物、昆虫和毒害草是草原生态系统的重要组分,对物质循环、能量流动等发挥着重要功能。然而,当其种群密度激增超过环境容纳量,并对草地生态、畜牧业生产以及人类健康等构成威胁时演变为有害生物。因此,科学防控有害生物和保护... 详细信息

草原啮齿动物、昆虫和毒害草是草原生态系统的重要组分,对物质循环、能量流动等发挥着重要功能。然而,当其种群密度激增超过环境容纳量,并对草地生态、畜牧业生产以及人类健康等构成威胁时演变为有害生物。因此,科学防控有害生物和保护生物多样性对于维系草地生态动态平衡和促进草地畜牧业可持续发展具有重要意义。制定草原有害生物防治指标是科学防控草原有害生物的前提,更是草原有害生物防治管理系统科学决策的依据。害鼠防治指标主要依据不同鼠种单位面积有效洞口数或新鼠丘数及秃斑占比制定;害虫防治指标主要依据不同害虫的种群密度制定;毒害草防治指标主要依据不同害草类型的植被盖度制定。本研究概述了我国草原有害生物防治指标制定的历史和现状,解读了新制定草原有害生物防治指标的思路,展望了未来草原有害生物防治指标体系建设。

关键词：天然草原啮齿动物草原昆虫毒害草生态平衡防治成效