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Leaf pigment retrieval using the PROSAIL model: Influence of uncertainty in prior canopy-structure information

The Crop Journal 2022年第5期10卷 1251-1263页

作者： Jia Sun Lunche wang Shuo Shi Zhenhai Li Jian Yang Wei Gong shaoqiang wang Torbern Tagesson Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeoscienceWuhan 430079HubeiChina Department of Physical Geography and Ecosystem Science Lund UniversityLund 117 SE-22100Sweden State Key Laboratory of Information Engineering in Surveying Mappingand Remote SensingWuhan UniversityWuhan 430079HubeiChina Key Laboratory of Quantitative Remote Sensing in Ministry of Agriculture and Rural Affairs Beijing Research Center for Information Technology in AgricultureBeijing 100097China Department of Geosciences and Natural Resource Management University of CopenhagenCopenhagen 1172Denmark

Leaf pigments are critical indicators of plant photosynthesis,stress,and physiological *** of radiative transfer models(RTMs)is a promising method for robustly retrieving leaf biochem-ical traits from canopy observations,and adding prior information has been effective in alleviating the“ill-posed”problem,a major challenge in model *** structure parameters,such as leaf area index(LAI)and average leaf inclination angle(ALA),can serve as prior information for leaf pigment *** canopy spectra simulated from the PROSAIL model,we estimated the effects of uncertainty in LAI and ALA used as prior information for lookup table-based inversions of leaf chlorophyll(C _(ab))and car-otenoid(C_(ar)).The retrieval accuracies of the two pigments were increased by use of the priors of LAI(RMSE of C_(ab) from 7.67 to 6.32μg cm^(-2),C_(ar) from 2.41 to 2.28μg cm^(-2))and ALA(RMSE of C_(ab) from 7.67 to 5.72μg cm^(-2),C_(ar) from 2.41 to 2.23μg cm^(-2)).However,this improvement deteriorated with an increase of additive and multiplicative uncertainties,and when 40% and 20% noise was added to LAI and ALA respectively,these priors ceased to increase retrieval *** using an experimental winter wheat dataset also showed that compared with C_(ar),the estimation accuracy of C_(ab) increased more or deteriorated less with uncertainty in prior canopy *** study demonstrates possible limita-tions of using prior information in RTM inversions for retrieval of leaf biochemistry,when large uncer-tainties are present.

关键词： Leaf pigment PROSAIL model Canopy structure Chlorophyll content Leaf area index Leaf angle distribution

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Changes of net primary productivity in China during recent 11 years detected using an ecological model driven by MODIS data

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Frontiers of Earth Science 2013年第1期7卷 112-127页

作者： Yibo LIU Weimin JU Honglin HE shaoqiang wang Rui SUN Yuandong ZHANG Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Nanjing University Nanjing 210093 China International Institute for Earth System Science Nanjing University Nanjing 210093 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing 100875 China Key Laboratory of Forest Ecology and Environment State Forestry Administration Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing 100091 China

Net primary productivity （NPP） is an important component of the terrestrial carbon cycle. Accurately mapping the spatial-temporal variations of NPP in China is crucial for global carbon cycling study. In this study the process-based Boreal Ecosystem Productivity Simulator （BEPS） was employed to study the changes of NPP in China＇s ecosystems for the period from 2000 to 2010. The BEPS model was first validated using gross primary productivity （GPP） measured at typical flux sites and forest NPP measured at different regions. Then it was driven with leaf area index （LAI） inversed from the Moderate Resolution Imaging Spectroradiometer （MODIS） reflec- tance and land cover products and meteorological data interpolated from observations at753 national basic meteorological stations to simulate NPP at daily time steps and a spatial resolution of 500m from January 1, 2000 to December 31, 2010. Validations show that BEPS is able to capture the seasonal variations of tower-based GPP and the spatial variability of forest NPP in different regions of China. Estimated national total of annual NPP varied from 2.63 to 2.84Pg ***-1, averaging 2.74Pg ***-1 during the study period. Simulated terrestrial NPP shows spatial patterns decreasing from the east to the west and from the south to the north, in association with land cover types and climate. South-west China makes the largest contribution to the national total of NPP while NPP in the North-west account for only 3.97% of the national total. During the recent 11 years, the temporal changes of NPP were heterogamous. NPP increased in 63.8% of China＇s landmass, mainly in areas north of the Yangtze River and decreased in most areas of southern China, owing to the low temperature freezing in early 2008 and the severe drought in late 2009.

关键词： temporal and spatial variations NPP remotesensing MODIS data BEPS model

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A new vegetation index combination for leaf carotenoid-tochlorophyll ratio: minimizing the effect of their correlation

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International Journal of Digital Earth 2023年第1期16卷 272-288页

作者： Chunmei He Jia Sun Yuwen Chen Lunche wang Shuo Shi Feng Qiu shaoqiang wang Torbern Tagesson Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeosciencesWuhanPeople’s Republic of China Department of Physical Geography and Ecosystem Science Lund UniversityLundSweden State Key Laboratory of Information Engineering in Surveying Mappingand Remote SensingWuhan UniversityWuhanPeople’s Republic of China International Institute for Earth System Science Jiangsu Provincial Key Laboratory of Geographic Information Science and TechnologyNanjing UniversityNanjingPeople’s Republic of China Department of Geosciences and Natural Resource Management University of CopenhagenCopenhagenDenmark

The ratio of leaf carotenoid to chlorophyll(Car/Chl)is an indicator of vegetation photosynthesis,development and responses to ***,the correlation between Car and Chl,and their overlapping absorption in the visible spectral domain pose a challenge for optical remote sensing of their *** study aims to investigate combinations of vegetation indices(VIs)to minimize the influence of Car-Chl correlation,thus being more sensitive to the variability in the ratio across vegetation species and *** sensitive to Car and Chl variability were combined into four candidates of combinations,using a simulated dataset from the PROSPECT *** VI combinations were then tested using six simulated datasets with different Car-Chl correlations,and evaluated against four independent *** ratio of the carotenoid triangle ratio index(CTRI)with the red-edge chlorophyll index(CIred-edge)was found least influenced by the Car-Chl correlation and demonstrated a superior ability for estimating Car/Chl *** with published VIs and two machine learning algorithms,CTRI/CIred-edge also showed the optimal performance in the fourfield *** new VI combination could be useful to provide insights in spatiotemporal variability in the leaf Car/Chl ratio,applicable for assessing vegetation physiology,phenology,and response to environmental stress.

关键词： Leaf carotenoids content leaf chlorophyll content PROSPECT model ratio of Car to Chl vegetation index

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奥氏体转变温度以上变形时应变速率对低碳钢动态软化行为的影响

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热加工工艺 2024年第11期53卷 82-85,90页

作者：刘永超王少强王鹏程桑学科丁宁刘珑许慧霞郭卫民金雷科技股份公司山东济南271105 山东省材料失效分析与安全评估工程技术中心山东省分析测试中心齐鲁工业大学(山东省科学院) 山东济南250014

利用Gleeble-1500热模拟试验机,将一低碳微合金钢在Ac3温度以上(950℃)进行了4种不同的应变速率(10、7、3、1 s^(-1))的压缩变形,然后淬火处理。对高温变形的应力应变曲线用双微分法进行变换,发现材料变形过程中主要有两种软化机制,分... 详细信息

利用Gleeble-1500热模拟试验机,将一低碳微合金钢在Ac3温度以上(950℃)进行了4种不同的应变速率(10、7、3、1 s^(-1))的压缩变形,然后淬火处理。对高温变形的应力应变曲线用双微分法进行变换,发现材料变形过程中主要有两种软化机制,分别为动态相变和动态再结晶,随变形速率的增加,材料发生软化的两个临界应力呈线性升高的趋势;两个临界应变则随应变速率变化不大。用金相显微镜观察观察了材料淬火后的金相组织,发现材料内的Widmanstätten铁素体板条宽度随应变速率的增加而逐渐变细,多边形铁素体的数目随应变速率的增加而增加;Widmanstätten铁素体板条一般为平行或垂直关系,而垂直关系的Widmanstätten铁素体板条并不呈现严格的直角,而是偏离一定的角度。

关键词：低碳钢动态再结晶动态相变双微分法应变速率

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基于人工智能系统的CT定量分析诊断肺结节浸润性的价值

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安徽医学 2024年第7期45卷 849-853页

作者：王振云王少强邱晓辉解福友宋贤亮亳州市人民医院影像中心安徽亳州236800 亳州市人民医院胸外科安徽亳州236800

目的探讨人工智能(AI)量化参数评估肺结节浸润程度的临床价值。方法回顾性分析2021年11月至2023年9月在亳州市人民医院住院治疗的114例经手术病理证实的肺腺癌患者临床资料,并根据病理结果分为非浸润组(n=72)、浸润组(n=42)。比较两组... 详细信息

目的探讨人工智能(AI)量化参数评估肺结节浸润程度的临床价值。方法回顾性分析2021年11月至2023年9月在亳州市人民医院住院治疗的114例经手术病理证实的肺腺癌患者临床资料,并根据病理结果分为非浸润组(n=72)、浸润组(n=42)。比较两组一般资料和AI量化参数之间的差异,采用logistic回归分析影响肺腺癌浸润程度的因素,以受试者工作特征(ROC)曲线评估量化参数对肺腺癌浸润程度的预测价值。结果两组一般资料(年龄、性别)和12个量化参数(熵、CT平均值、CT最小值、3D长径、体积、质量、长短径平均值、最大面面积、偏度、CT最大值、CT值方差和表面积)比较,差异均有统计学意义(P<0.05)。logistic回归结果显示,CT平均值、熵是影响肺腺癌发生浸润性的独立危险因素,CT最小值是影响肺腺癌发生浸润性的独立保护因素(P<0.05)。ROC结果显示,CT平均值、熵和CT最小值预测肺腺癌发生浸润性的曲线下面积(AUC)分别为0.630、0.888、0.890,3者联合预测的AUC为0.955,优于各自单独检测(P<0.05)。结论CT量化参数CT平均值、熵及CT最小值水平可为临床诊断肺腺癌浸润性提供帮助,3项指标联合检测可进一步提高诊断价值。

关键词：人工智能浸润性肺腺癌肺结节 CT定量分析

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Nano-Bacillus Calmette-Guérin immunotherapies for improved bladder cancer treatment

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第7期25卷 557-567页

作者： Sheng ZENG shaoqiang XING Yifei ZHANG Haifeng wang Qian LIU Department of Urology Tianjin First Central HospitalTianjin 300192China Department of Urology First Central Clinical CollegeTianjin Medical UniversityTianjin 300192China

Cancer immunotherapy has rapidly become the fourth mainstream treatment alternative after surgery,radiotherapy,and chemotherapy,with some promising *** aims to kill tumor cells by mobilizing or stimulating cytotoxic immune ***,the clinical applications of tumor immunotherapies are limited owing to a lack of adequate delivery pathways and high ***,nanomaterials and genetic engineering have shown great potential in overcoming these limitations by protecting the delivery of antigens,activating targeted T cells,modulating the immunosuppressive tumor microenvironment,and improving the treatment *** Calmette-Gué;rin(BCG)is a live attenuated Mycobacterium bovis vaccine used to prevent tuberculosis,which was first reported to have antitumor activity in *** therapy can activate the immune system by inducing various cytokines and chemokines,and its specific immune and inflammatory responses exert antitumor *** was first used during the 1970s as an intravesical treatment agent for bladder cancer,which effectively improved immune antitumor activity and prevented tumor *** recently,nano-BCG and genetically engineered BCG have been proposed as treatment alternatives for bladder cancer due to their ability to induce stronger and more stable immune *** this study,we outline the development of nano-BCG and genetically engineered BCG for bladder cancer immunotherapy and review their potential and associated challenges.

关键词： Bladder cancer Bacillus Calmette-Gué rin vaccine Nanocarrier Genetic engineering Immunotherapy

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Carbon Dynamics in Woody Biomass of Forest Ecosystem in China with Forest Management Practices under Future Climate Change and Rising CO_2 Concentration

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Chinese Geographical Science 2013年第5期23卷 519-536页

作者： ZHOU Lei wang shaoqiang Georg KINDERMANN YU Guirui HUANG Mei Robert MICKLER Florian KRAXNER SHI Hao GONG Yazhen Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources Research University of Chinese Academy of Sciences Ecosystems Services and Management International Institute for Applied Systems Analysis Alion Science and Technology Inc.Raleigh Renmin University of China

It is critical to study how different forest management practices affect forest carbon sequestration under global climate change regime. Previous researches focused on the stand-level forest carbon sequestration with rare investigation of forest carbon stocks influ- enced by forest management practices and climate change at regional scale. In this study, a general integrative approach was used to simulate spatial and temporal variations of woody biomass and harvested biomass of forest in China during the 21st century under dif- ferent scenarios of climate and CO2 concentration changes and management tasks by coupling Integrated Terrestrial Ecosystem Carbon budget （InTEC） model with Global Forest Model （G4M）. The results showed that forest management practices have more predominant effects on forest stem stocking biomass than climate and CO2 concentration change. Meanwhile, the concurrent future changes in cli- mate and CO2 concentration will enhance the amounts of stem stocking biomass in forests of China by 12%-23% during 2001-2100 relative to that with climate change only. The task for maximizing stem stocking biomass will dramatically enhance the stem stocking biomass from 2001~100, while the task for maximum average increment will result in an increment of stem stocking biomass before 2050 then decline. The difference of woody biomass responding to forest management tasks was owing to the current age structure of forests in China. Meanwhile, the sensitivity of long-term woody biomass to management practices for different forest types （coniferous forest, mixed forest and deciduous forest） under changing climate and CO2 concentration was also analyzed. In addition, longer rotation length under future climate change and rising CO2 concentration scenario will dramatically increase the woody biomass of China during 2001~100. Therefore, our estimation indicated that taking the role of forest management in the carbon cycle into the consideration at regional or national

关键词： global forest model carbon stock forest management rotation length harvested biomass future climate change

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Thermoelectric Properties of an Indandione-Terminated Quinoidal Compound:Effect of the n-Type Dopants

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Chinese Journal of Chemistry 2024年第9期42卷 997-1003页

作者： Yingying Liu Cheng wang Tianzuo wang Fei Jiao shaoqiang Dong Yunfeng Deng Yanhou Geng School of Materials Science and Engineering and Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin Universityand Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin 300072China Institute of Molecular Aggregation Science Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Molecular Optoelectronic Science Department of ChemistrySchoolof ScienceTianjin UniversityTianjin300072China Joint Schoolof NationalUniversity of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New City FuzhouFujian350207China

The investigation of n-type doping holds a significant interest for the application of ***,the doping of an indandione-terminated compound Q-4F with a singlet open-shell ground state was studied using two n-dopants N-DMBI and *** of these two dopants can effectively dope Q-4F due to the large offset between the singly occupied molecular orbital(SOMO)of dopants and the lowest unoccupied molecular orbital(LUMO)of Q-4F.N-DMBI has a higher doping ability than LCV as demonstrated by the UV-vis-NIR and EPR ***,in comparison to N-DMBI doped Q-4F,LCV doped system exhibits much higher electrical conductivity and power factor due to its unperturbed molecular packing and favorable morphology after *** optimal conductivity of LCV doped Q-4F is 7.16×10^(-2)±0.16 S·cm^(-1) and the highest power factor reaches 12.3±0.85μW·m–1·K^(-2).These results demonstrate that the modulation of n-dopants is a powerful strategy to balance the doping efficiency and microstructure toward a maximum thermoelectric performance.

关键词： n-Doping Indandione Quinoidal compounds Organic thermoelectrics Electron transfer Organic electronics Energy conversion

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Preface to Special Topic on Atmospheric Greenhouse Gas Measurement and Application in China

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Advances in Atmospheric Sciences 2020年第6期37卷 555-556页

作者： Pengfei HAN Ning ZENG Bo YAO Weijian ZHOU Liqi CHEN shaoqiang wang Honggang LV Wei XIAO Lingyun ZHU Jiaping XU State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Department of Atmospheric and Oceanic Science University of MarylandCollege ParkMD 20742USA Meteorological Observation Centre of China Meteorological Administration Beijing 100081China Institute of Earth Environment Chinese Academy of SciencesXi’an 710061China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China National Marine Environment Forecasting Center Beijing 100081China Nanjing University of Information Science&Technology Nanjing 210044China Shanxi Institute of Meteorological Sciences Taiyuan 030002China Jiangsu Institute of Meteorological Sciences Nanjing 210009China

China initiated a national carbon trading market in December *** and actions to reduce greenhouse gas(GHG)emissions require consistent,reliable and timely information on GHG *** monitoring and modeling studies provide GHG emission estimates to evaluate and guide progress towards emission *** monitoring has mainly focused on global-scale background networks over the last few decades,while recent efforts have been made on regional and urban scales,such as projects in the Beijing-Tianjin-Hebei city cluster,in Paris,Washington-Baltimore.

关键词： national market city cluster

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Effects of afforestation on soil carbon turnover in China＇s subtropical region

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Journal of Geographical Sciences 2011年第1期21卷 118-134页

作者： wang shaoqiang LIU Jiyuan ZHANG Cheng YI Chuixiang WU Weixing Key Lab of Ecosystem Network and Modelling Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Queens College City University of New York New York USA

Afforestation in China＇s subtropics plays an important role in sequestering CO2 from the atmosphere and in storage of soil carbon （C）. Compared with natural forests,plantation forests have lower soil organic carbon （SOC） content and great potential to store more C. To better evaluate the effects of afforestation on soil C turnover,we investigated SOC and its stable C isotope （δ13C） composition in three planted forests at Qianyanzhou Ecological Experimental Station in southern China. Litter and soil samples were collected and analyzed for total organic C,δ13C and total nitrogen. Similarly to the vertical distribution of SOC in natural forests,SOC concentrations decrease exponentially with depth. The land cover type （grassland） before plantation had a significant influence on the vertical distribution of SOC. The SOC ？13C composition of the upper soil layer of two plantation forests has been mainly affected by the grass biomass 13C composition. Soil profiles with a change in photosynthetic pathway had a more complex 13C isotope composition distribution. During the 20 years after plantation establishment,the soil organic matter sources influenced both the δ13C distribution with depth,and C replacement. The upper soil layer SOC turnover in masson pine （a mean 34% of replacement in the 10 cm after 20 years） was more than twice as fast as that of slash pine （16% of replacement） under subtropical conditions. The results demonstrate that masson pine and slash pine plantations cannot rapidly sequester SOC into long-term storage pools in subtropical China.

关键词： soil organic carbon stable carbon isotope plantation forest

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