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Species spatial distributions in a warm-temperate deciduous broad-leaved forest in China

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Journal of Forestry Research 2020年第4期31卷 1187-1194页

作者： Huiyan Gu Jiaxin Li Guang Qi shunzhong wang School of Forestry Northeast Forestry UniversityHarbin 15004People’s Republic of China Key Laboratory of Ecological Restoration in Hilly Areas Pingdingshan UniversityPingdingshan 467000People’s Republic of China State Key Laboratory of Vegetation and Environment Change Institute of BotanyChinese Academy of SciencesBeijing 100093People’s Republic of China

Spatial distribution is fundamental for understanding species coexistence mechanisms in forest *** we comprehensively explored fine-scale spatial patterns of tree species in a secondary warm-temperate deciduous broad-leaved forest community in north *** distribution patterns were *** functional traits had no significant effects on their spatial *** aggregation intensity decreased with increasing DBH and *** multivariate linear stepwise regression showed that abundance and maximum DBH were correlated with the aggregation *** results partially confirm that species attributes(abundance,DBH)and habitat heterogeneity may primarily contribute to spatial patterns and species coexistence in this secondary forest.

关键词： Spatial distributions Aggregation intensity Species functional trait Secondary warm-temperate deciduous broad-leaved forest

Coarse woody debris features of a warm temperate deciduous broad-leaved forest,northern China

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Journal of Forestry Research 2021年第3期32卷 1105-1114页

作者： Fang Ma Liwen Zhuang shunzhong wang Weiguo Sang Minzu University of China No.27Zhongguancun NandajieHaidian DistrictBeijing 100081People’s Republic of China Heilongjiang Academy of Forestry Science No 134 Haping RoadNangang DistrictHarbin 150081People’s Republic of China Key Lab of Environment and Vegetation Change Institute of BotanyChinese Academy of SciencesNo.20 Xiangshan NanxincunHaidian DistrictBeijing 100093People’s Republic of China

Stocking and structural composition of a deciduous broad-leaved forest were determined to predict coarse woody debris quantity by quantifying the empirical relationships between these two *** most ecologically significant families by stem density were Salicaceae,Betulaceae,Fagaceae,and Aceraceae.P opulus davidiana was the most dominant species followed by B etula dahurica,Quercus mongolica,and Acer *** four species accounted for 69.5%of total *** small-diameter species characterized the coarse woody debris showing a reversed J-shaped *** coarse debris of ***,***,and *** mainly comprised the 10–20 cm size class,whereas *** debris was mainly in the 5–10 cm size *** spatial patterns of different size classes of coarse woody debris were analyzed using the g-function to determine the size of the tree at its *** results indicate that the spatial patterns at the 0–50 m scale shifted gradually from an aggregated to a random *** some species,the larger coarse debris might change from an aggregated to a random distribution more *** the importance of coarse woody debris in forest ecosystems,its composition and patterns can improve understanding of community structure and *** aggregation pattern might be due to density dependence and self-thinning effects,as well as by succession and *** four dominant species across the different size classes showed distinct aggregated distribution features at different spatial *** suggests a correlation between the dominant species population,size class,and aggregated distribution of coarse woody debris.

关键词： Tree mortality Diversity Size class Forest dynamic plot

Temporal shifts in the explanatory power and relative importance of litter traits in regulating litter decomposition

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Forest Ecosystems 2022年第6期9卷 755-763页

作者： Zhaolin Sun Peng Tian Xuechao Zhao Yanping wang shunzhong wang Xiangmin Fang Qingkui wang Shengen Liu School of Forestry and Landscape Architecture Anhui Agricultural UniversityHefei230036China Huitong Experimental Station of Forest Ecology CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyShenyang110016China University of Chinese Academy of Sciences Beijing100049China College of Forestry Taishan Forest Ecosystem Research StationShandong Agricultural UniversityTai'an271018China Institute of Botany The Chinese Academy of SciencesBeijing100093China College of Forestry Jiangxi Agricultural UniversityNanchang330032China College of Biological and Pharmaceutical Sciences China Three Gorges UniversityYichang443000China

Background:Litter traits critically affect litter decomposition from local to global ***,our understanding of the temporal dynamics of litter trait-decomposition linkages,especially their dependence on plant functional type remains ***:We decomposed the leaf litter of 203 tree species that belong to two different functional types(deciduous and evergreen)for 2 years in a subtropical forest in *** Weibull residence model was used to describe the different stages of litter decomposition by calculating the time to 10%,25%and 50%mass loss(Weibull t_(1/10),t_(1/4),and t_(1/2)respectively)and litter mean residence time(Weibull MRT).The resulting model parameters were used to explore the control of litter traits(e.g.,N,P,condensed tannins and tensile strength)over leaf litter decomposition across different decomposition ***:The litter traits we measured had lower explanatory power for the early stages(Weibull t_(1/10)and t_(1/4))than for the later stages(Weibull t_(1/2)and MRT)of *** relative importance of different types of litter traits in influencing decomposition changed dramatically during decomposition,with physical traits exerting predominant control for the stages of Weibull t_(1/10)and MRT and nutrient-related traits for the stages of Weibull t_(1/4),and t_(1/2).Moreover,we found that litter decomposition of the early three stages(Weibull t_(1/10),t_(1/4),and t_(1/2))of the two functional types was controlled by different types of litter traits;that is,the litter decomposition rates of deciduous species were predominately controlled by nutrient-related traits,while the litter decomposition rates of evergreen species were mainly controlled by carbon-related ***:This study suggests that litter trait-decomposition linkages vary with decomposition stages and are strongly mediated by plant functional type,highlighting the necessity to consider their temporal dynamics and plant functional types for impr

关键词： Decomposition model Decomposition stage Litter decay Litter physical traits Litter quality Plant functional type

Gradient coil design with enhanced shielding constraint for a cryogen-free superconducting MRI system

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Magnetic Resonance Letters 2024年第1期4卷 1-9页

作者： Yaohui wang Weimin wang Hui Liu shunzhong Chen Feng Liu Qiuliang wang Institute of Electrical Engineering Chinese Academy of SciencesBeijing100190China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing100049China School of Electronics&Institute of Biomedical Engineering Peking University&Shenzhen Graduate SchoolShenzhen518055China School of Information Technology and Electrical Engineering The University of QueenslandSt LuciaBrisbaneQLD4072Australia

The relatively fragile low-temperature stability of cryogen-free superconducting magnetic resonance imaging(MRI)magnets requires the careful management of exogenous heat sources.A strongly shielded gradient magnetic field is important for the optimal operation of cryogen-free MRI *** this study,we present an enhanced shielding method incorporating a regionalized stray field constraining *** optimizing the constraint parameters,we could develop engineering-feasible gradient coil schemes without increasing system complexity but with the stray field intensity reduced by *** real measurement in an integrated MRI system,the developed gradient assembly demonstrated good performance and supported to output images of excellent *** findings suggested that the proposed method could potentially form a useful design paradigm for cryogen-free MRI magnets.

关键词： MRI Gradient coil Superconducting magnet Cryogen-free Magnetic shielding

Achievement of a high-performance 30-tesla metal-as-insulated user superconducting magnet

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Science China(Technological Sciences) 2024年第6期67卷 1974-1978页

作者： ZHOU BenZhe DAI YinMing ZHANG ZiLi LIU Hui wang YaoHui wang Lei wang Hui CHEN shunzhong wang KangShuai CHEN Yong LIU JianHua wang QiuLiang Institute of Electrical Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences

Strong magnetic fields can be used to manipulate the states of matter and induce unique ***,they enable a thorough investigation of the intrinsic properties of matter through the application of the nuclear magnetic resonance(NMR)*** versatile nature of strong magnetic fields facilitates the discovery of novel phenomena and patterns.

关键词： effect NMR versatile

人为管理措施诱导土壤微生物磷与土壤微生物碳氮内稳态解耦的代谢证据

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Journal of Plant Ecology 2023年第6期16卷 185-196页

作者： Lihua Zhang Lizhi Jia Liyuan He David A.Lipson Yihui wang shunzhong wang Xiaofeng Xu College of Life and Environmental Sciences Minzu University of ChinaBeijing 100081China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Biology Department San Diego State UniversitySan DiegoCA 92182USA

微生物化学计量学理论能够预测微生物对碳(C)、氮(N)、磷(P)的同化作用具有比例耦合性。这种耦合性被量化为稳态值,用于计算内稳性系数(H)。C、N、P的H值协变量表明,微生物对C、N、P的同化作用是耦合的。因此,在本文中我们利用全球数据... 详细信息

微生物化学计量学理论能够预测微生物对碳(C)、氮(N)、磷(P)的同化作用具有比例耦合性。这种耦合性被量化为稳态值,用于计算内稳性系数(H)。C、N、P的H值协变量表明,微生物对C、N、P的同化作用是耦合的。因此,在本文中我们利用全球数据集研究微生物C、N、P的H值在不同生物群落中的时空动态变化。研究结果表明,土地利用和人为管理措施导致P与C、N的代谢在时间和空间上解耦,并且我们利用结构方程模型(SEM)分析结果表明,土壤因子主导P的微生物动态平衡,而土壤元素含量则主导C和N的微生物动态平衡。利用机器学习算法得出的微生物P与微生物C和N的对比因子也证实了这一结果。总的来说,我们的研究强调了在营养循环中人为管理措施对微生物角色转变具有重要的影响。

关键词：碳氮磷微生物的内稳性管理措施

Digitally determining forest inventory units with an ecological classification system

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Science China(Technological Sciences) 2006年第z1期49卷 118-127页

作者： TANG Una, wang Qingli, Guofan Shao, DAI Limin, wang shunzhong, LI Xiufen & XU Dong Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China Graduate University of Chinese Academy of Sciences, Beijing 100101, China Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Institute of Applied Ecology Chinese Academy of Sciences

Management-level forest resource data in China were obtained with a combination of two forest inventories. However, inconsistencies in the spatial attributes of forest data vary between the two inventory types and between two inventories of the same type. The inconsistencies make it inconvenient for long-term forest management planning with digital technologies. Ecological Land Types (ELTs) and Ecological Land Type Phases (ELTPs) have been mapped in selected forestry regions in northeast China, where important forest industries are located. The boundaries of ELTs are determined by geomorphic conditions, which are quantified by Digital Elevation Models (DEM); ELTPs are classified by overlaying ELTs with forest vegetation data layers that are obtained with both remotely sensed and ground data. The ELTPs represent the divisions of land in terms of both natural and human-induced forest conditions, and therefore they are reliable units for forest inventories and management. This paper introduces a case study for digitally determining forest inventory units in Benxi City, Liaoning Province, northeast China. The general objective of the study was to explain how a compatible forest inventory system should be designed and why the compatible forest inventory system was significant to digital forestry in China.

关键词： forest inventory, ecological classification, ELT mapping, ELTP mapping, geographic information systems, forest management.

Quantifying soil erosion with GIS-based RUSLE under different forest management options in Jianchang Forest Farm

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中国科学：技术科学英文版 2006年第z1期49卷 160-166页

作者： ZHANG Hengming, wang Qingli, DAI Limin, Guofan Shao, TANG Una, wang shunzhong & GU Huiyan Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China Graduate University of Chinese Academy of Sciences, Beijing 100101, China Department of Forestry and Natural Resources, Purdue University, Lafayette IN47901, USA Northeast Forestry University, Harbin 150040, China Institute of Applied Ecology Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Quantitatively estimating soil erosion with an integration of geographic information system (GIS) and the revised universal soil loss equation (RUSLE) under four different exposed soil proportion scenarios caused by forest management practices was studied at Jianchang Forest Farm. The GIS provided means of input data generation required by RUSLE model and allowed a spatial assessment of the erosion hazard over the study area. Four exposed soil proportion scenarios of 5%, 10%, 20% and 30% were tested with the GIS-based RUSLE model to evaluate soil erosion hazard. The predicted soil erosion potentials were classified into five categories in order to provide valuable aids for management planning.

关键词： geographic information system, RUSLE, soil erosion, forest management.

Modeling diameter distribution of the broadleaved-Korean pine mixed forest on Changbai Mountains of China

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Science China(Technological Sciences) 2006年第z1期49卷 177-188页

作者： wang shunzhong, DAI Limin, LIU Guohua, YUAN Jianqiong, ZHANG Hengmin & wang Qingli Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China Graduate University of Chinese Academy of Sciences, Beijing 100039, China State Key Lab of Systems Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China Institute of Applied Ecology Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

The broadleaved-Korean pine mixed forest is a native vegetation in the Changbai Mountains, northeast China. The probability density functions including the normal, negative exponential, Weibull and finite mixture distribution, were used to describe the diameter distributions of the species groups and entire forest stand. There is a strong correlation between parameters and mean DBH except the shape parameters in the mixture distribution. The diameter classes of species and entire forest stand showed not negative exponential but normal and "S" distribution. The mixture function was better than normal and Weibull to describe the model distribution. The location parameter had an effect on the estimated frequency in the first diameter class, when the estimated location parameter was bigger than the lower limit of the first diameter class.

关键词： broadleaved-Korean pine mixed forest, diameter distribution, finite mixture distribution.