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Natural forests exhibit higher organic carbon concentrations and recalcitrant carbon proportions in soil than plantations: a global data synthesis

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JOURNAL OF FORESTRY RESEARCH 2024年第1期35卷 1-11页

作者： nie, xiuqing Wang, Hui Wang, Jian Liu, Shirong Chinese Acad Forestry Ecol & Nat Conservat Inst Key Lab Forest Ecol & Environm Natl Forestry & Gra 2 Dongxiaofu Beijing 100091 Peoples R China

Different chemical compositions of soil organic carbon (SOC) affect its persistence and whether it significantly differs between natural forests and plantations remains unclear. By synthesizing 234 observations of SOC chemical compositions, we evaluated global patterns of concentration, individual chemical composition (alkyl C, O-alkyl C, aromatic C, and carbonyl C), and their distribution evenness. Our results indicate a notably higher SOC, a markedly larger proportion of recalcitrant alkyl C, and lower easily decomposed carbonyl C proportion in natural forests. However, SOC chemical compositions were appreciably more evenly distributed in plantations. Based on the assumed conceptual index of SOC chemical composition evenness, we deduced that, compared to natural forests, plantations may have higher possible resistance to SOC decomposition under disturbances. In tropical regions, SOC levels, recalcitrant SOC chemical composition, and their distributed evenness were significantly higher in natural forests, indicating that SOC has higher chemical stability and possible resistance to decomposition. Climate factors had minor effects on alkyl C in forests globally, while they notably affected SOC chemical composition in tropical forests. This could contribute to the differences in chemical compositions and their distributed evenness between plantations and natural stands.

关键词： Global data synthesis Natural forest Plantations Soil organic carbon Soil organic carbon chemical composition STATE C-13 NMR SPATIAL-DISTRIBUTION MICROBIAL COMMUNITY MATTER FRACTIONS QUALITY SEQUESTRATION STABILIZATION DECOMPOSITION DIVERSITY

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世界自然遗产保护与可持续发展的国际经验评析——以美国和英国为例

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自然保护地 2024年第3期4卷 54-64页

作者：陈永哲王枫张宇聂秀青李桂静中国林业科学研究院森林生态环境与自然保护研究所国家林业和草原局森林生态环境重点实验室北京100091 中国林学会北京100091

【目的】我国拥有全世界数量最多的世界自然遗产。尽管我国相关的保护机构与法律法规较多,但对我国自然遗产的保护仍需要进一步完善。借鉴不同国家,特别是发达国家的世界自然遗产保护经验,对提升中国的遗产保护发展水平,让人类共同的财... 详细信息

【目的】我国拥有全世界数量最多的世界自然遗产。尽管我国相关的保护机构与法律法规较多,但对我国自然遗产的保护仍需要进一步完善。借鉴不同国家,特别是发达国家的世界自然遗产保护经验,对提升中国的遗产保护发展水平,让人类共同的财富世代相传意义重大。【方法】采用文献研究法收集了美国和英国在世界自然遗产保护方面的相关案例与经验,基于各自国家的异同点,提出对中国具有重要借鉴意义的宝贵经验。【结果】研究分析了美国、英国的世界自然遗产保护与管理经验,对美国和英国的保护法律框架、管理体系、社区参与和人才支持等方面的做法进行全面梳理。【结论】借鉴美国、英国的世界自然遗产保护经验,中国未来可进一步建立完善相关法律法规体系,强化管理,统筹规划布局,建立多方共赢机制,培养专业人才队伍,提高人才待遇,合理分配偏远地区遗产地人才需要。

关键词：世界自然遗产遗产保护可持续发展国际经验对比研究

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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

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Cloud-Type-Dependent 1DVAR Algorithm for Retrieving Hydrometeors and Precipitation in Tropical Cyclone Nanmadol from GMI Data

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Advances in Atmospheric Sciences 2024年第3期41卷 407-419页

作者： Linjun HAN Fuzhong WENG Hao HU xiuqing HU School of the Environment China University of Geosciences(Wuhan)Wuhan 430074China Chinese Academy of Meteorological Sciences Beijing 100081China CMA Earth System Modeling and Prediction Centre Beijing 100081China Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites National Satellite Meteorological Center(National Center for Space Weather)of CMABeijing 100081China

Understanding the structure of tropical cyclone(TC)hydrometeors is crucial for detecting the changes in the distribution and intensity of *** this study,the GMI brightness temperature and cloud-dependent 1DVAR algorithm were used to retrieve the hydrometeor profiles and surface rain rate of TC Nanmadol(2022).The Advanced Radiative Transfer Modeling System(ARMS)was used to calculate the Jacobian and degrees of freedom(△DOF)of cloud water,rainwater,and graupel for different channels of GMI in convective *** retrieval results were compared with the Dual-frequency Precipitation Radar(DPR),GMI 2A,and IMERG *** is shown that from all channels of GMI,rain water has the highest△DOF,at *** to the radiance Jacobian to atmospheric state variables,cloud water emission dominates its *** rain water,the emission of channels 1–4 dominates *** with the GMI 2A precipitation product,the 1DVAR precipitation rate has a higher correlation coefficient(0.713)with the IMERG product and can better reflect the location of TC *** the TC eyewall,the highest radar echo top indicates strong *** the melting layer where Ka-band attenuation is strong,the double frequency difference of DPR data reflects the location of the *** DPR drop size distribution(DSD)product shows that there is a significant increase in particle size below the melting layer in the spiral rain ***,the particle size may be one of the main reasons for the smaller rain water below the melting layer retrieved from 1DVAR.

关键词： cloud-dependent 1DVAR hydrometeor precipitation GMI DPR

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Strengthening Network Security: Deep Learning Models for Intrusion Detectionwith Optimized Feature Subset and Effective Imbalance Handling

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Computers, Materials & Continua 2024年第2期78卷 1995-2022页

作者： Bayi Xu Lei Sun xiuqing Mao Chengwei Liu Zhiyi Ding School of Cyber Science and Engineering Zhengzhou UniversityZhengzhou450000China Three Academy Information Engineering UniversityZhengzhou450001China The 3rd Research Department Nanjing Research Institute of Electronic EngineeringNanjing210007China

In recent years,frequent network attacks have highlighted the importance of efficient detection methods for ensuring cyberspace *** paper presents a novel intrusion detection system consisting of a data prepro-cessing stage and a deep learning model for accurately identifying network *** have proposed four deep neural network models,which are constructed using architectures such as Convolutional Neural Networks(CNN),Bi-directional Long Short-Term Memory(BiLSTM),Bidirectional Gate Recurrent Unit(BiGRU),and Attention *** models have been evaluated for their detection performance on the NSL-KDD *** enhance the compatibility between the data and the models,we apply various preprocessing techniques and employ the particle swarm optimization algorithm to perform feature selection on the NSL-KDD dataset,resulting in an optimized feature ***,we address class imbalance in the dataset using focal ***,we employ the BO-TPE algorithm to optimize the hyperparameters of the four models,maximizing their detection *** test results demonstrate that the proposed model is capable of extracting the spatiotemporal features of network traffic data *** binary and multiclass experiments,it achieved accuracy rates of 0.999158 and 0.999091,respectively,surpassing other state-of-the-art methods.

关键词： Intrusion detection CNN BiLSTM BiGRU attention

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Bimetallic CoNi single atoms supported on three-dimensionally ordered mesoporous chromia: highly active catalysts for n-hexane combustion

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Green Energy & Environment 2024年第7期9卷 1122-1137页

作者： xiuqing Hao Yuxi Liu Jiguang Deng Lin Jing Jia Wang Wenbo Pei Hongxing Dai Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution Control Key Laboratory of Advanced Functional Materials Education Ministry of China Laboratory of Catalysis Chemistry and Nanoscience Department of Chemical Engineering Faculty of Environment and Life Beijing University of Technology

Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile organic compounds （VOCs）.In this work,we prepared the mesoporous chromia-supported bimetallic Co and Ni single-atom （Co1Ni1/meso-Cr2O3） and bimetallic Co and Ni nanoparticle (CoNPNiNP/mesoCr2O3) catalysts adopting the one-pot polyvinyl pyrrolidone （PVP）-and polyvinyl alcohol （PVA）-protecting approaches,*** results indicate that the Co1Ni1/meso-Cr2O3catalyst exhibited the best catalytic activity for n-hexane (C6H14) combustion (T50%and T90%were 239 and 263℃ at a space velocity of 40,000 mL g-1h-1;apparent activation energy and specific reaction rate at 260℃ were 54.7 kJ mol-1and 4.3×10-7mol g-1cats-1,respectively),which was associated with its higher (Cr5++Cr6+) amount,large n-hexane adsorption capacity,and good lattice oxygen mobility that could enhance the deep oxidation of n-hexane,in which Ni1was beneficial for the enhancements in surface lattice oxygen mobility and low-temperature reducibility,while Co1preferred to generate higher contents of the high-valence states of chromium and surface oxygen species as well as adsorption and activation of n-hexane.n-Hexane combustion takes place via the Mars van Krevelen（MvK） mechanism,and its reaction pathways are as follows:n-hexane→olefins or 3-hexyl hydroperoxide→3-hexanone,2-hexanone or 2,5-dimethyltetrahydrofuran→2-methyloxirane or 2-ethyl-oxetane→acrylic acid→COx→CO2and H2O.

关键词： Three-dimensional ordered mesoporous chromium oxide Supported bimetallic single-atom catalyst Cobalt−nickel single atoms n -Hexane combustion Catalytic reaction mechanism

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Pd Pt VO_(x)/CeO_(2)-ZrO_(2):Highly efficient catalysts with good sulfur dioxide-poisoning reversibility for the oxidative removal of ethylbenzene

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Journal of Environmental Sciences 2024年第4期138卷 153-166页

作者： Jia Wang Yuxi Liu Jiguang Deng Lin Jing xiuqing Hao Xing Zhang Xiaohui Yu Hongxing Dai Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaLaboratory of Catalysis Chemistry and NanoscienceDepartment of Chemical EngineeringFaculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

The PdPtVO_(x)/CeO_(2)-ZrO_(2)(PdPtVO_(x)/CZO)catalysts were obtained by using different approaches,and their physical and chemical properties were determined by various *** activities of these materials in the presence of H_(2)O or SO_(2)were evaluated for the oxidation of ethylbenzene(EB).The PdPtVO_(x)/CZO sample exhibited high catalytic activity,good hydrothermal stability,and reversible sulfur dioxide-poisoning performance,over which the specific reaction rate at 160℃,turnover frequency at 160℃(TOF_(Pd or Pt)),and apparent activation energy were 72.6 mmol/(g_(Pt)·sec)or 124.2 mmol/(g_(Pd)·sec),14.2 sec^(-1)(TOF_(Pt))or 13.1 sec^(-1)(TOF_(Pd)),and 58 k J/mol,*** large EB adsorption capacity,good reducibility,and strong acidity contributed to the good catalytic performance of PdPtVO_(x)/*** activity of PdPtVO_(x)/CZO decreased when 50 ppm SO_(2)or(1.0 vol.%H_(2)O+50 ppm SO_(2))was added to the feedstock,but was gradually restored to its initial level after the SO_(2)was cut *** good reversible sulfur dioxide-resistant performance of PdPtVO_(x)/CZO was associated with the facts:(i)the introduction of SO_(2)leads to an increase in surface acidity;(ii)V can adsorb and activate SO_(2),thus accelerating formation of the SO_(x)^(2-)(x=3 or 4)species at the V and CZO sites,weakening the adsorption of sulfur species at the PdPt active sites,and hence protecting the PdPt active sites to be not poisoned by SO_(2).EB oxidation over PdPtVO_(x)/CZO might take place via the route of EB→styrene→phenyl methyl ketone→benzaldehyde→benzoic acid→maleic anhydride→CO_(2)and H_(2)O.

关键词： Ceria-zirconia Supported palladium-platinum-vanadium catalyst Volatile organic compound Ethylbenzene oxidation Sulfur dioxide resistance

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Synthesis of carbon dots with predictable photoluminescence by the aid of machine learning

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Nano Research 2024年第3期17卷 1984-1989页

作者： Chenyu Xing Gaoyu Chen Xia Zhu Jiakun An Jianchun Bao Xuan Wang xiuqing Zhou Xiuli Du Xiangxing Xu Jiangsu Key Laboratory of Biofunctional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China School of Mathematical Sciences Nanjing Normal UniversityNanjing 210023China State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

Carbon dots(CDs)have wide application potentials in optoelectronic devices,biology,medicine,chemical sensors,and quantum techniques due to their excellent fluorescent ***,synthesis of CDs with controllable spectrum is challenging because of the diversity of the CD components and *** this report,machine learning(ML)algorithms were applied to help the synthesis of CDs with predictable photoluminescence(PL)under the excitation wavelengths of 365 and 532 *** combination of precursors was used as the *** PL peaks of the strongest intensity(λ_(s))and the longest wavelength(λ_(l))were used as target *** six investigated ML models,the random forest(RF)model showed outstanding)performance in the prediction of the PL peaks.

关键词： carbon dots(CDs) synthesis photoluminescence(PL) machine learning(ML) PL prediction

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Comparative proteomics reveals the response and adaptation mechanisms of white Hypsizygus marmoreus against the biological stress caused by Penicillium

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Food Science and Human Wellness 2024年第3期13卷 1645-1661页

作者： xiuqing Yang Sizhu Li Xiaohang Li Chenxiao Zhang Meijie Liu Lizhong Guo Lin Liu Hao Yu Shandong Provincial Key Laboratory of Applied Mycology School of Life SciencesQingdao Agricultural UniversityQingdao 266109China

White Hypsizygus marmoreus is a popular edible *** mycelium is easy to be contaminated by Penicillium,which leads to a decrease in its quality and *** could compete for limited space and nutrients through rapid growth and produce a variety of harmful gases,such as benzene,aldehydes,phenols,etc.,to inhibit the growth of *** mycelium.A series of changes occurred in *** proteome after contamination when detected by the label-free tandem mass spectrometry(MS/MS)*** proteins with up-regulated expression worked together to participate in some processes,such as the non-toxic transformation of harmful gases,glutathione metabolism,histone modification,nucleotide excision repair,clearing misfolded proteins,and synthesizing glutamine,which were mainly used in response to biological *** proteins with down-regulated expression are mainly related to the processes of ribosome function,protein processing,spliceosome,carbon metabolism,glycolysis,and *** reduction in the function of these proteins affected the production of the cell components,which might be an adjustment to adapt to growth *** study further enhanced the understanding of the biological stress response and the growth restriction adaptation mechanisms in edible *** also provided a theoretical basis for protein function exploration and edible mushroom food safety research.

关键词： Hypsizygus marmoreus Penicillium Proteomics Biological stress response Adaptation

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三江源地区高寒灌丛生物量空间分布格局

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应用与环境生物学报 2016年第4期22卷 538-545页

作者：聂秀青杨路存李长斌周国英中国科学院西北高原生物研究所西宁810008 中国科学院大学北京100049 中国科学院藏药研究重点实验室西宁810008

生物量在地上与地下的分配是植物生长策略的反映,对于研究生态系统碳储量和碳循环有着重要的意义.采用收获法对灌丛群落与物种的地上、地下生物量进行测定,并分析温度和降雨量等气候因素对灌丛群落地上和地下生物量及构成的影响.同时选... 详细信息

生物量在地上与地下的分配是植物生长策略的反映,对于研究生态系统碳储量和碳循环有着重要的意义.采用收获法对灌丛群落与物种的地上、地下生物量进行测定,并分析温度和降雨量等气候因素对灌丛群落地上和地下生物量及构成的影响.同时选择三江源地区4种典型的灌丛植物,百里香杜鹃(Rhododendron thymifolium Maxim.)、山生柳(Salix oritrepha Schneid.)、金露梅(Potentilla fruticosa Linn.)和鲜卑花(Sibiraea laevigata(Linn)Maxim.),进行地上、地下生物量研究.结果显示:三江源灌丛群落的地上生物量介于209.88-3 632.34 g/m^2之间,地下生物量介于178.81-2 262.03 g/m^2之间,根冠比(R/S)介于0.40-2.57之间;物种的地上生物量介于1.83-3 632.34 g/m^2之间,地下生物量介于1.22-2 262.03 g/m^2之间,根冠比(R/S)介于0.23-2.63之间.灌丛群落与物种的地上、地下生物量拟合的斜率分别为0.66和0.96,前者与1存在显著性差别,后者与1没有显著性差别.这说明灌丛群落与物种的地上、地下生物量分配分别呈异速分配关系与等速分配关系,百里香杜鹃和鲜卑花的地上与地下生物量分配属于等速分配关系,金露梅和山生柳属于异速分配关系.本研究表明三江源高寒灌丛生物量大小与年均温度的变化关系密切;年均温度与年均降雨量都不能明显地改变根冠比(R/S).

关键词：三江源地区高寒灌丛生物量分配关系气候因子

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