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Vegetation Mapping for Regional Ecological Research and Management: A Case of the Loess Plateau in China

Chinese Geographical Science 2020年第3期30卷 410-426页

作者： LIU Yuanxin LYU Yihe bai yingfei ZHANG Buyun TONG Xiaolin State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sci-encesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China The Grain for Green Project Management Office of Yan'an Municipality Yan'an 716000China The Grain for Green Project Management Office of Ansai Dis-trict Yan'an 717400China

Vegetation maps are fundamental for regional-scale ecological research. However, information is often not sufficiently up to date for such research. The Loess Plateau is a key area for vegetation restoration projects and a suitable area for regional ecological research. To carry out regional vegetation mapping based on the principles of hierarchical classification, object-oriented methods, visual interpretation, and accuracy assessment, this study integrated land cover, high-resolution remote sensing images, background environmental data, bioclimate zoning data, and field survey data from the Loess Plateau. To further clarify the implications of vegetation mapping, we compared the deviation of the 2015 vegetation map of the Loess Plateau(VMLP) and the widely used vegetation map of China(VMC)(1 : 1 000 000) for the expressed vegetation information and the evaluation of ecosystem services. The results indicated that 1) the vegetation of the Loess Plateau could be divided into 9 vegetation type groups and 18 vegetation types with classification accuracies of 87.76% and 83.97%, respectively;2) the distribution of vegetation had obvious zonal regularity;3) a deviation of 29.56 × 10^4 km^2 occurred when the vegetation coverage area was quantified with the VMC;4) the vegetation classification accuracy affected the ecosystem service assessment, the total water yield of the Loess Plateau calculated by the VMC and other required parameters was overestimated by 2.2 × 10^6 mm in 2015. Because vegetation mapping is a basic and important activity, that requires greater attention, this study provides supporting data for subsequent multivariate vegetation mapping and vegetation management for conservation and restoration.

关键词： vegetation map Loess Plateau spatial pattern vegetation classification ecosystem service

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A framework for the regional critical zone classi?cation: the case of the Chinese Loess Plateau

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National Science Review 2019年第1期6卷 14-18页

作者： Yihe Lü Jian Hu Bojie Fu Paul Harris Lianhai Wu Xiaolin Tong yingfei bai Alexis J.Comber State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Joint Center for Global Change Studies Institute of Qinghai-Tibetan Plateau Southwest Minzu University Sustainable Agriculture Sciences Rothamsted Research

The concept of the Earth’s Critical Zone(CZ)—the near-surface heterogeneous environment of our planet—was originally defined to include the land surface,vegetation canopy, rivers, lakes and shallow seas [1]. CZ accommodates interactions among air, water, soil, rock and living organisms, and determines the availability of life-sustaining resources needed for the well-being and sustainability of human society. Therefore, there are new opportunities for integrative studies of

关键词： the case of the Chinese Loess Plateau CLP CZ

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黄土高原农牧交错带湿地重构对鸟类多样性的影响

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水利学报 2018年第9期49卷 1097-1108页

作者：刘广全白应飞张亭王中强胡彩娥中国水利水电科学研究院北京100038 国际泥沙研究培训中心北京100048 延安市退耕还林工程管理办公室陕西延安716000 神木市林业局陕西神木719300 榆林市林业局陕西榆林719000

为客观评价生态脆弱地带湿地生态系统变化对鸟类多样性的影响,2017—2018年采用样带法对陕北榆林湿地生态系统重构前后的水鸟变化开展了系统调查。研究结果表明:研究区共有水鸟106种,隶属9目20科55属,分别占陕西全省和全国水鸟总数的88%... 详细信息

为客观评价生态脆弱地带湿地生态系统变化对鸟类多样性的影响,2017—2018年采用样带法对陕北榆林湿地生态系统重构前后的水鸟变化开展了系统调查。研究结果表明:研究区共有水鸟106种,隶属9目20科55属,分别占陕西全省和全国水鸟总数的88%和40%,其中列入国家Ⅰ、Ⅱ级和省级重点保护鸟类的分别有2、11和14种;列入CITES保护名录的Ⅰ、Ⅱ级重点保护鸟类分别有1、7种;列入IUCN红色名录等级易危、近危和低度关注的分别有3、4和96种;列入国家林业局"三有"名录的有90种;属古北界、广布和东洋界鸟类的分别占65%、25%和10%。种群数量以旅鸟和夏候鸟为主,分别占58%和34%,迷鸟、冬候鸟和留鸟较少,南北不同区域的居留型差异较大;以蒙古高原荒漠湿地鸟类为主,鸻形目、雁形目、鹳形目和鹤形目的鸟类分别占45%、25%、10%和9%,且其数量比湿地恢复保护前增加明显,其余鸊鷉目、鹈形目、红鹳目、隼形目、佛法僧目等的鸟类所占比例较少,数量变化不大。随着湿地生态系统功能不断恢复、区域生态环境不断改善和人们保护鸟类意识的日益增强,以及全球气候变暖,荒漠和黄土区鸟类相互逐渐扩散,研究区内鸟的种类和数量逐年增多,在2010年前记载鸟类共232种,2017年增到280种,2017年调查发现水鸟新记录18种。该研究可为全球最大的遗鸥繁殖地(红碱淖湿地)和繁殖种群及中国鸟类迁移通道保护提供基本依据。

关键词：鸟类多样性响应湿地重构黄土高原农牧交错带

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浅水中波浪载荷对半潜平台拖航运动响应和拖揽张力影响

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科技导报 2025年第2期43卷 97-107页

作者：张涛白旭昝英飞江苏科技大学船舶与海洋工程学院哈尔滨工程大学船舶工程学院

针对浅水航道水域较浅且环境条件复杂恶劣的现象，以浮筒宽高比过大的新型半潜平台为研究对象，基于时域分析理论和浅水波浪理论，通过数值模型对比分析不同有义波高、谱峰周期、浪向角、拖航速度和拖揽长度对浅水海域半潜平台拖航运动... 详细信息

针对浅水航道水域较浅且环境条件复杂恶劣的现象，以浮筒宽高比过大的新型半潜平台为研究对象，基于时域分析理论和浅水波浪理论，通过数值模型对比分析不同有义波高、谱峰周期、浪向角、拖航速度和拖揽长度对浅水海域半潜平台拖航运动响应和拖揽张力的影响。结果表明：波浪高度越高，平台垂荡、缆绳张力越大；谱峰周期越长，纵摇、缆绳张力越小；浪向角对横纵摇影响较大，极值呈凹凸型分布；不同工况下的新型半潜平台横纵摇均≤5°，满足拖航规范要求；缆绳张力受航速和波高的影响较大，当波高达到5 m，拖揽张力超过安全范围，可以通过降低拖航速度、缩短缆绳长度等措施规避风险。

关键词：浅水海域波浪载荷半潜平台运动响应拖揽张力

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Disordered hyperuniformity and thermal transport in monolayer amorphous carbon

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 145-152页

作者： Nianjie Liang Yuxi Wang bai Song Department of Energy and Resources Engineering Peking UniversityBeijing 100871China Department of Advanced Manufacturing and Robotics Peking UniversityBeijing 100871China

Disordered hyperuniformity(DHU)is a recently discovered novel state of amorphous systems characterized by strongly suppressed density fluctuations at large length scales as in crystalline materials,which offers great potential for achieving unusual mechanical,electronic,and photonic ***,despite the fundamental and technological importance of thermal transport in amorphous solids,the effect of DHU remains largely ***,we theoretically study thermal transport in a class of two-dimensional DHU materials—monolayer amorphous carbon(MAC).Beginning with a perfect graphene lattice,we continuously apply Stone-Wales transformations to generate a series of MAC models with varied degrees of disorder and defects,which are quantified through comprehensive structural analysis including the so-called hyperuniformity index(H),where a smaller H indicates a higher degree of ***,we conduct molecular dynamics simulations to obtain the thermal conductivity(κ).A significant correlation between the thermal transport behavior and degree of hyperuniformity is observed,with the room-temperatureκdecreasing from 26.3 to 5.3 W m^(-1)K^(-1)while H is tuned from 0.0004 to ***,two distinct transport regimes are identified,including a nearly-DHU regime at small H(<0.005)whereκdrops sharply and a non-DHU region at larger H whereκbecomes relatively ***-resolved analysis reveals longer lifetime and higher participation ratio for the heat carriers in nearly-DHU MAC,implying that the hidden long-range correlations could support extended modes that enhance *** work highlights the impact of DHU on the thermal properties of amorphous materials and represents a conceptual advancement that is worthy of future exploration.

关键词： disordered hyperuniformity thermal transport amorphous material two-dimensional monolayer amorphous carbon

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An improved GCN−TCN−AR model for PM_(2.5) predictions in the arid areas of Xinjiang,China

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Journal of Arid Land 2025年第1期17卷 93-111页

作者： CHEN Wenqian bai Xuesong ZHANG Na CAO Xiaoyi School of Information and Control Engineering Qingdao University of TechnologyQingdao 266520China Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China

As one of the main characteristics of atmospheric pollutants,PM_(2.5) severely affects human health and has received widespread attention in recent *** to predict the variations of PM_(2.5) concentrations with high accuracy is an important *** PM_(2.5) monitoring stations in Xinjiang Uygur Autonomous Region,China,are unevenly distributed,which makes it challenging to conduct comprehensive analyses and ***,this study primarily addresses the limitations mentioned above and the poor generalization ability of PM_(2.5) concentration prediction models across different monitoring *** chose the northern slope of the Tianshan Mountains as the study area and took the January−December in 2019 as the research *** the basis of data from 21 PM_(2.5) monitoring stations as well as meteorological data(temperature,instantaneous wind speed,and pressure),we developed an improved model,namely GCN−TCN−AR(where GCN is the graph convolution network,TCN is the temporal convolutional network,and AR is the autoregression),for predicting PM_(2.5) concentrations on the northern slope of the Tianshan *** GCN−TCN−AR model is composed of an improved GCN model,a TCN model,and an AR *** results revealed that the R2 values predicted by the GCN−TCN−AR model at the four monitoring stations(Urumqi,Wujiaqu,Shihezi,and Changji)were 0.93,0.91,0.93,and 0.92,respectively,and the RMSE(root mean square error)values were 6.85,7.52,7.01,and 7.28μg/m^(3),*** performance of the GCN−TCN−AR model was also compared with the currently neural network models,including the GCN−TCN,GCN,TCN,Support Vector Regression(SVR),and *** GCN−TCN−AR outperformed the other current neural network models,with high prediction accuracy and good stability,making it especially suitable for the predictions of PM_(2.5)*** study revealed the significant spatiotemporal variations of PM_(2.5)***,the PM_(2.5) concentrations exhibited cle

关键词： air pollution PM_(2.5) concentrations graph convolution network(GCN)model temporal convolutional network(TCN)model autoregression(AR)model northern slope of the Tianshan Mountains

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Protonated carbon nitride for rapid photocatalytic sterilization via synergistic oxidative damage and physical destruction

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Journal of Environmental Sciences 2025年第3期149卷 188-199页

作者： Xiaobiao Zhu Chunhong Xu Jie Mao Yizhen Zhang Yaohui bai Department of Environmental Science and Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China

Photocatalytic disinfection is an eco-friendly strategy for countering bacterial pollution in aquatic *** strategies have been devised to facilitate the generation of reactive oxygen species(ROS)within photocatalysts,ultimately leading to the eradication of ***,the significance of the physical morphology of photocatalysts in the context of sterilization is frequently obscured,and the progress in the development of physical-chemical synergistic sterilization photocatalysts has been relatively ***,graphitic carbon nitride(g-C_(3)N_(4))is chemically protonated to expose more sharp *** fluorescence and EIS results indicate that the protonation can accelerate photogenerated carrier separation and enhance ROS ***,the sharp edges on the protonated g-C_(3)N_(4)facilitate the physical disruption of cell walls for further promoting oxidative *** C_(3)N_(4)demonstrated superior bactericidal performance than that of pristine g-C_(3)N_(4),effectively eliminating Escherichia coli within 40 minutes under *** work highlights the significance of incorporating physical and chemical synergies in photocatalyst design to enhance the disinfection efficiency of photocatalysis.

关键词： Protonated Photocatalytic Sterilization Synergistic Oxidative Damage Physical Destruction

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The transformation of nor-seco-cucurbit[10]uril to cucurbit[5]uril and cucurbit[8]uril controlled by its own concentration

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Chinese Chemical Letters 2025年第2期36卷 373-377页

作者： Shaojie Deng Peihua Ma Qinghong bai Xin Xiao Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province Department of Chemistry Guizhou University

Nor-seco-cucurbit[10]uril(ns-CB[10]) is a kinetic product with unique structure. The single bridged methylene in its structure makes the molecular cavity of ns-CB[10] more deformable when compared to ordinary cucurbit[n]uril, reducing its structural stability. Repeated experiments showed that ns-CB[10] gradually cracks in an acidic solution and changes the specificity of cucurbit[5]uril(CB[5]) and cucurbit[8]uril(CB[8]) under more robust acidic solutions and when heated. A series of experiments were designed to study the transformation behavior of ns-CB[10]. It was found that the concentration of ns-CB[10] was correlated with the content distribution of CB[5] and CB[8]. This study explores the influencing factors and mechanisms of the transformation of ns-CB[10] to CB[5] and CB[8]. The results are of great significance for the application of ns-CB[10], understanding the formation mechanism of cucurbit[n]urils. Furthermore,it provides a new pathway for synthesizing new cucurbit[n]urils.

关键词： Concentration control Cracking Mechanism Nor-seco-cucurbituril Transformation

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Gas-Solid Flow,Combustion Characteristics,and Gas Emissions in a 75 t/h CFB Boiler Based on the CPFD Method

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Journal of Thermal Science 2025年第1期34卷 323-336页

作者： HUANG Xiankun bai Zhang ZHU Xiaoli WANG Shuoshuo MU Lin GONG Liang College of New Energy China University of Petroleum(East China)Qingdao 266580China Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education School of Energy and Power EngineeringDalian University of TechnologyDalian 116024China

A 3D simulation using Computational Particle Fluid Dynamics(CPFD)methods was used to calculate coal combustion in a 75 t/h industrial-scale circulating fluidized bed(CFB)*** characteristics,gas-solid flow characteristics,and gaseous pollutant emissions of CFB boilers from combustion ignition to stable operation were systematically evaluated in this *** show that the temperature distribution is relatively uniform throughout the *** the combustion process unfolds within the boiler,the gas composition curve strikingly portrays the inverse correlation between CO_(2)and O_(2)*** the combustion reaction progresses,it becomes evident that the concentration of CO_(2)progressively increases,while the concentration of O_(2)concurrently *** inverse relationship underscores the fundamental combustion reaction,where carbon-based fuels react with oxygen to produce carbon dioxide and release ***,a comprehensive analysis has revealed that,from ignition to stable combustion,both nitric oxide(NO)and sulfur dioxide(SO_(2))emissions exhibit a declining *** reduction in pollutant generation is attributed to the improvement in combustion *** complete combustion leads to lower levels of unburned hydrocarbons,which are prone to NO ***,the sulfur content in the fuel is more efficiently oxidized to sulfur trioxide(SO_(3))or bound in sulfates,reducing SO_(2)*** steady state in the simulation,the SO_(2)mass flow rate varies significantly with the furnace height,gradually increasing from 0.07 kg·s^(-1)at 4 m at the bottom of the furnace to a peak of 0.078 kg·s^(-1)at 8 m in the center,and then decreasing to 0.06 kg·s^(-1)at 20m at the top of the furnace.

关键词： circulating fluidized bed particle flow combustion CPFD modeling

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NaCl胁迫对侧柏幼苗生长及矿质离子吸收和分配的影响

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西北农林科技大学学报（自然科学版） 2018年第9期46卷 60-66页

作者：唐晓倩白应飞刘广亮刘广全中国水利水电科学研究院北京100038 国家林业局盐碱地研究中心北京100091 延安市退耕还林工程管理办公室陕西延安716000 吴起县林业局陕西吴起717600 国际泥沙研究培训中心北京100048

【目的】探讨侧柏幼苗对盐生环境的适应性及耐盐机制。【方法】以当年生侧柏幼苗为材料,通过温室土培模拟盐分不同梯度胁迫试验,研究不同浓度(0,100,200mmol/L)NaCl胁迫对侧柏幼苗生物量积累及其不同器官(根、茎、叶)K^+、Na^+、Ca^(2+)... 详细信息

【目的】探讨侧柏幼苗对盐生环境的适应性及耐盐机制。【方法】以当年生侧柏幼苗为材料,通过温室土培模拟盐分不同梯度胁迫试验,研究不同浓度(0,100,200mmol/L)NaCl胁迫对侧柏幼苗生物量积累及其不同器官(根、茎、叶)K^+、Na^+、Ca^(2+)、Mg^(2+)吸收、运输与分配的影响。【结果】(1)盐胁迫不同程度地促进了侧柏幼苗根系生长,但显著抑制了幼苗生物量的积累。(2)随着NaCl浓度的升高,侧柏幼苗各器官中Na^+含量增加,且Na^+含量在不同浓度盐胁迫下具有相同的分配规律,即根>叶>茎;随着Na^+含量的升高,各器官中K+含量显著减少,Ca2+含量在根和叶中显著升高。(3)各器官中K^+/Na^+、Ca2+/Na+和Mg2+/Na+总体随NaCl胁迫浓度的升高呈下降趋势,叶片和茎部离子比值始终高于根部。(4)随着NaCl胁迫浓度的增加,根部到茎部的离子选择性运输系数SK,Na、SCa,Na、SMg,Na逐渐降低;而茎部到叶部的SK,Na、SCa,Na、SMg,Na在低浓度盐胁迫时显著升高,在高浓度盐胁迫下受到抑制。【结论】侧柏幼苗对NaCl胁迫具有一定的耐受性,这与根系对Na+的聚积和限制作用以及低浓度盐胁迫下地上部对K+、Ca2+、Mg2+选择性运输能力的提高有关。

关键词： NaCl胁迫侧柏幼苗生物量矿质离子

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