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Spatial heterogeneity of the driving forces of cropland change in China

Science China Earth sciences 2005年第12期48卷 2231-2240页

作者： liu xuhua1,{1.,{2.,2.3 1. institute of geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, China 2. Graduate School of the chinese academy of sciences, beijing 1.0039, China 3. College of Arts and sciences of beijing Union University, beijing 1.0083, China 4. School of Forestry and Wildlife sciences, Auburn University, Auburn, Alabama, AL36849, USA 1. institute of {1.{2. and natural resources research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the{1. 100039 Beijing China 3. School of Forestry and Wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of {1. Union University 100083 Beijing China

By using digital satellite remote sensing data acquired in 1.87―1.89 and 1.99―2.00 and GIS com{1.ed with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in China. The results indicated that the cropland change in the study period was constrained by {2.al factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of China, natural condition changes and {2.al background were the main constraints and drivers, while in Eastern China, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in China recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, China.

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Modeling the impacts of climate change on China's agriculture

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Journal of geographical {1. 2001年第2期11卷 149-160页

作者： liu Hui~1, LI Xiu-bin~1, Guenther Fischer~2. SUN Lai-xiang~2.(1. {2. of geographic {2. and natural resources research, CAS, beijing 100101, China 2. International {2. for Applied System Analysis, A-2.61 Laxenburg, Austria) institute of {1.{2. and natural resources research CAS International institute for Applied System Analysis A-2361 Laxenburg Austria

The impacts of climate change on China's agriculture are measured based on Ricardian model. By using county-level cross-sectional data on agricultural net revenue, climate, and other economic and geographical data for 1.1.5 agriculture-dominated counties in the period of 1.85-1.91. we find that both higher temperature and more precipitation will have overall positive impact on China's agriculture. However, the impacts vary seasonally and regionally. Higher temperature in all seasons except spring increases agricultural net revenue while more precipitation is beneficial in winter but is harmful in summer. Applying the model to five climate scenarios in the {1.{1.s and {1.50s shows that the North, the Northeast, the Northwest, and the Qinghai-Tibet Plateau would always benefit from climate change while the South and the Southwest may be negatively affected. For the East and the Central China, most scenarios show that they may benefit from climate change. In conclusion, climate change would be beneficial to the whole China.

关键词： climate change Ricardian model China's agriculture

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Mapping China’s offshore mariculture based on dense time-series optical and radar data

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International Journal of Digital Earth 2022年第1期15卷 1326-1349页

作者： Xiaoliang liu Zhihua {1. Xiaomei Yang Yueming liu bin liu Junyao Zhang Ku Gao Dan meng Yaxin Ding State Key Laboratory of resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingPeople’s Republic of China University of chinese academy of sciences BeijingPeople’s Republic of China

Due to the weak information about cultural targets in the complex marine environment,an omission problem exists in large-scale mariculture extraction using single-view and single-source *** overcome this problem,we developed a mariculture extraction method that combines dense time-series Sentinel-{1.and Sentinel-1.data.A high-precision chinese mariculture distribution map for {1.{1. was produced with an overall accuracy of 94.00%and a kappa coefficient of *** results show that(1.the total area of mariculture was 1.73{1.9.{1. ha on the national scale,which was significantly larger than the previous studies(459595.70 and {1.59{1..{1. ha,respectively),with Shandong Province(39.09%)having the largest proportion;({1.China’s mariculture presented a spatial distribution characteristic of‘Denser North and Sparser South’,and mariculture was centralized in the coastal zones of the northern provinces(60.76%)rather than the southern provinces;(3)the official production statistics and remote sensing-derived mariculture area revealed a highly corresponding trend at the provincial level,with an R{1.reaching 0.78,which is much higher than the 0.07 and 0.41.values of the comparison *** results directly provide data reference for mariculture production estimation and site selection or ideas for mariculture extraction in other regions and globally.

关键词： Aquaculture mariculture multi-source remote sensing time-series China’s coastal zone

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青藏高原表土磁化率空间分布特征及影响因素

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土壤学报 2024年第2期61卷 361-371页

作者：陈雅敏宋效东刘峰叶明亮张楚张甘霖土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所) 南京210008 中国科学院大学北京100049 中国科学院南京地理与湖泊研究所流域地理科学重点实验室南京210008

土壤磁化率是古环境重建的常用代用指标,对表土磁化率与现代环境的关系研究有助于理解磁化率产生差异的原因。当前,区域尺度上土壤磁化率变化成因认识尚不清楚,限制了磁化率作为古环境重建重要代用指标的精准应用。本研究系统调查了青... 详细信息

土壤磁化率是古环境重建的常用代用指标,对表土磁化率与现代环境的关系研究有助于理解磁化率产生差异的原因。当前,区域尺度上土壤磁化率变化成因认识尚不清楚,限制了磁化率作为古环境重建重要代用指标的精准应用。本研究系统调查了青藏高原的2.4个样点表层(发生层A层)土样,测定土壤磁化率和其他土壤属性,结合母质、气候、地形和植被等数据,阐明青藏高原地区土壤磁化率空间变化特征及其主要影响因素。结果表明:(1.不同母质类型之间,表层土壤磁化率(χ_(lf))无显著差异,百分频率磁化率(χ_(fd)%)差异显著,表现为黄土和砂页岩风化物>冰碛物和结晶盐风化物,其他母质类型之间无显著差异;不同土地利用之间,表层土壤χ_(lf)无显著差异,χ_(fd)%差异显著:森林和旱地>草地>荒地。(2.各因子对土壤磁化率影响表现为植被>理化性质>地形>母质。(3)空间分布上,χ_(lf)与χ_(fd)%均呈现由东南向西北降低的趋势。此外,χ_(lf)和χ_(fd)%的空间分布规律与青藏高原植被分区相吻合。因此,磁化率能更好地指示植被空间分布。

关键词：青藏高原表土磁化率气候

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N-(2.Phenoxy)ethyl imidazo[1.2.a]pyridine-3-carboxamides containing various amine moieties:Design,synthesis and antitubercular activity

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chinese Chemical Letters 2020年第2期31卷 409-412页

作者： Linhu Li Apeng wang {1. wang mingliang liu Kai Lv Zeyu Tao Chao Ma Xican Ma {1.g Han Aoyu wang Yu Lu institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Limin Chemical Co. Ltd.Xinyi 221422China beijing Key Laboratory of Drug Resistance Tuberculosis {1. Department of PharmacologyBeijing Tuberculosis and Thoracic Tumor Research InstituteBeijing Chest HospitalCapital Medical UniversityBeijing 100149China

Seven 2.6-disubstituted N-(2.phenoxy)ethyl imidazo[1.2.a]pyridine-3-carboxamide series containing various amine moieties were designed and synthesized as new anti-TB *** of them show excellent in vitro activity against both drug-sensitive MTB strain H37Rv and two MDR-MTB clinical isolates(MIC:2.0.030 μg/mL).Compounds 2.,5e and 5g display acceptable safety and pharmacokinetic profiles,opening a new direction for further development.

关键词： N-(2.Phenoxy)ethyl imidazo[1.2.α]pyridine Design Synthesis Antimycobacterial activity

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基于无人机遥感的盐渍化土壤有机质反演方法研究

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地球信息科学学报 2024年第3期26卷 736-752页

作者：王玮莹彭金榜朱婉雪杨斌刘振公华锐王俊栋杨婷娄金勇孙志刚中国科学院地理科学与资源研究所北京100101 中国科学院大学资源与环境学院北京100049 中科山东东营地理研究院东营257000 长光禹辰信息技术与装备(青岛)有限公司青岛266000

土壤有机质含量是衡量土壤肥力的重要指标,对粮食生产具有重要影响。我国滨海盐碱地分布广阔,土壤有机质呈现显著的空间异质性。传统的“实地采集-实验测量”的方法费时费力,难以快速描绘盐碱地区土壤有机质含量的空间分布特征。因此,... 详细信息

土壤有机质含量是衡量土壤肥力的重要指标,对粮食生产具有重要影响。我国滨海盐碱地分布广阔,土壤有机质呈现显著的空间异质性。传统的“实地采集-实验测量”的方法费时费力,难以快速描绘盐碱地区土壤有机质含量的空间分布特征。因此,采用遥感技术对土壤有机质含量进行高效且精准地反演,可以快速了解土壤肥力,从而调整与优化农业生产与管理。本研究以黄河三角洲典型滨海盐碱地裸土(0~1. cm土层)为研究对象,通过提取土壤的无人机遥感光谱与空间纹理信息,构建并筛选遥感指数。分别采用多元线性逐步回归、偏最小二乘以及随机森林模型对土壤有机质含量进行反演,并对比分析耕作与未耕作处理对反演的影响,同时探究融入对土壤盐分含量敏感的遥感信息是否可提高盐碱地区土壤有机质的反演精度。研究结果表明:(1.在土壤有机质含量反演中,随机森林模型的反演精度(R2.0.83~0.95)显著高于多元线性逐步回归(R2.0.2.~0.69)和偏最小二乘模型(R2.0.37~0.72.;(2.与未耕作土壤(R2.0.2.~0.95)相比,耕作处理下的土壤有机质的反演精度较高(R2.0.54~0.94),即土壤的耕作处理能提高光谱指数对于土壤有机质含量的响应,从而提升土壤有机质含量的反演精度,为更加精准地监测土壤有机质提供新思路;(3)融入遥感纹理信息或土壤盐分含量信息(盐分实测值和盐分敏感指数)可显著提高土壤有机质反演精度。本研究将为提升田块尺度滨海盐渍化农田的土壤有机质含量反演提供理论与技术支撑,从而促进滨海盐渍化地区现代化农业的发展。

关键词：土壤有机质反演无人机多光谱遥感土壤盐分光谱指数盐碱地裸土耕作未耕作

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Kinetics of FeSe_2.oxidation by ferric iron and its reactivity compared with FeS_2

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Science China Chemistry 2014年第9期57卷 1300-1309页

作者： MA bin NIE Zhe {1. ChunLi KANG {2. BARDELLI Fabrizio CHEN FanRong CHARLET Laurent beijing National Laboratory for Molecular {1. Fundamental Science Laboratory on Radiochemistry & Radiation ChemistryCollege of Chemistry and Molecular EngineeringPeking University Sino-French institute of Nuclear Engineering and Technology Sun Yat-sen University CAS Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of Sciences Environmental Geochemistry Group ISTerreUniversity of Grenoble I38041 GrenobleFrance

The mobility and bioavailability of selenium is a major health and environmental issue and a main concern for geological disposal of high-level radioactive waste. Chemically and/or microbially mediated oxidation of insoluble Se-bearing particulate, such as iron selenides, to dissolved and mobile phases controls the transport and distribution of Se in the environment. The oxidation of ferroselite （FeSe2. by ferric iron was investigated in anoxic conditions. The redox reaction can be represented by： FeSe2.＋ 2.e3＋ = 2.e^0 ＋ 3Fe2.. Kinetic studies indicated that the reaction can be described by second-order rate law, with rate constants of 0.49±0.01. 0.85±0.02. 1.84±0.04, and 3.2.±0.1. L mol^-1.s^-1.at pH 1.62. 1.87, 2.2., and 2.49, respectively. The positive correlation between reaction rate and pH implies that diffusion of Fe3＋ oxidant to the mineral surface is the rate-determining step. The strong reactivity of FeSe2.towards Fe^3＋ suggests that ferric iron may play a significant role in FeSe2.oxidation process （e.g., by Se^4＋, 02. etc.） and Se^0 should be the first reaction product. Also, it was shown that the reduction rate of Fe^3＋ or Se^4＋ by pyrite （FeS2. can be significantly increased in the presence of FeSe2. suggesting a stronger reactivity of FeSe2.compared with pyrite. The results obtained extend our knowledge about the subtle interaction between Se, pyrite and iron selenides in the environment, and give insight into the transfer of selenium from iron selenides to bio-available selenium （i.e., selenite and selenate） in the Se-rich environment.

关键词： high-level radioactive waste disposal ferroselite oxidative dissolution second-order rate law

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Water consumption and biodiversity:Responses to global emergency events

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Science Bulletin 2024年第16期69卷 2632-2646页

作者： Dandan Zhao Junguo liu Laixiang Sun Klaus Hubacek Stephan Pfister Kuishuang Feng Heran Zheng Xu Peng Daoping {1. Hong Yang Lei Shen Fei Lun Xu Zhao {2. Chen Marko Keskinen Shaohui Zhang Jialiang Cai Olli Varis Water&Development research Group Department of Built EnvironmentAalto UniversityEspoo 15200Finland School of Water Conservancy North China University of Water Resources and Electric PowerZhengzhou 450046China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Department of geographical {1. University of MarylandCollege Park 20742USA School of Finance and Management SOASUniversity of LondonLondon WC1H0XGUK Integrated research on Energy Environment and SocietyEnergy and Sustainability Research Institute GroningenUniversity of GroningenGroningen 9747AGthe Netherlands ETH Zurich Institute of Environmental EngineeringZurich 8093Switzerland The Bartlett School of Sustainable Construction University College LondonLondon WC1E6BTUK School of Business Jiangnan UniversityWuxi 214122China Department of Computer Science and Technology University of CambridgeCambridge CB21TNUK w2. Environmental Consulting GmbH Duebendorf 8600Switzerland Key Laboratory for Resource Use and Environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Land Science and Technology China Agricultural UniversityBeijing 100083China institute of Blue and Green Development Shandong UniversityWeihai 264209China Fudan Tyndall Center Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China School of Economics and Management Beihang UniversityBeijing 100191China International institute for Applied Systems Analysis Laxenburg A-2361Austria

Given that it was a once-in-a-century emergency event,the confinement measures related to the coronavirus disease 2.1.(COVID-1.)pandemic caused diverse disruptions and changes in life and work *** changes significantly affected water consumption both during and after the pandemic,with direct and indirect consequences on ***,there has been a lack of holistic evaluation of these ***,we propose a novel framework to study the impacts of this unique global emergency event by embedding an environmentally extended supply-constrained global multi-regional input-output model(MRIO)into the drivers-pressure-state-impact-response(DPSIR)*** framework allowed us to develop scenarios related to COVID-1. confinement measures to quantify country-sector-specific changes in freshwater consumption and the associated changes in biodiversity for the period of *** results suggest progressively diminishing impacts due to the implementation of COVID-1. vaccines and the socio-economic system’s self-adjustment to the new *** 2.2.,the confinement measures were estimated to decrease global water consumption by about 5.7% on average across all scenarios when compared with the baseline level with no confinement ***,such a decrease is estimated to lead to a reduction of around 5% in the related pressure on *** the interdependencies and interactions across global supply chains,even those countries and sectors that were not directly affected by the COVID-1. shocks experienced significant impacts:Our results indicate that the supply chain propagations contributed to 79% of the total estimated decrease in water consumption and 84%of the reduction in biodiversity loss on *** study demonstrates that the MRIO-enhanced DSPIR framework can help quantify resource pressures and the resultant environmental impacts across supply chains when facing a global emergency ***,we recommend the development o

关键词： Global emergency events Water-biodiversity causal effect COVID-1. Biodiversity MRIO-enhanced DPSIR framework Supply-chain network High-resolution water consumption dataset Supply-constrained multi-regional input-output(mixed MRIO)model

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Could the Recent Taal Volcano Eruption Trigger an El Ni?o and Lead to Eurasian Warming?

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Advances in Atmospheric sciences 2020年第7期37卷 663-670页

作者： Fei liu Chen XING Jinbao LI {1. {2. Jing CHAI Chaochao GAO Gang HUANG Jian liu Deliang CHEN School of Atmospheric sciences and Guangdong Province Key Laboratory for Climate Change and {1. Disaster Studies Sun Yat-sen UniversityZhuhai 519082China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Earth System Modeling and Climate Dynamics research Center Nanjing University of Information Science and TechnologyNanjing 210044China Department of Geography University of Hong KongPokfulamHong Kong Department of Atmospheric sciences and International Pacific {1. Center University of Hawaii at ManoaHonoluluHI 96822USA Department of Environmental Science Zhejiang UniversityHangzhou 310058China State key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory for Virtual geographic Environment Ministry of EducationJiangsu Provincial State Key Laboratory Cultivation Base of Geographical Environment EvolutionSchool of Geography ScienceNanjing Normal UniversityNanjing 210023China Department of Earth sciences University of GothenburgGothenburg 40530Sweden

The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines.A recent eruption occurred on 1.0}January 2.2.(Fig.1.),and this volcano is still active with the occurrence of volcanic *** eruption has become a deep concern worldwide,not only for its damage on local society,but also for potential hazardous consequences on the Earth’s climate and environment.

关键词： Volcano Philippines worldwide

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Urban expansion patterns and their driving forces based on the center of gravity-GTWR model:A case study of the beijing-Tianjin-Hebei urban agglomeration

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Journal of geographical {1. 2020年第2期30卷 297-318页

作者： wang Haijun ZHANG {1. {2. Yaolin {2. Yanfang XU Shan ZHAO Yuntai CHEN Yuchen HONG Song School of resources and Environmental Science Wuhan UniversityWuhan 430079China Key Laboratories of geographic Information Systems Ministry of EducationWuhan UniversityWuhan 430079China Collaborative Innovation Center for Geospatial Information Science Wuhan UniversityWuhan 430079China institute of {1.{2. and natural resources research CASBeijing 100101China China Land Survey and Planning institute Beijing 100035China

research into urban expansion patterns and their driving forces is of great significance for urban agglomeration development planning and *** this paper,we reveal the multi-dimensional characteristics of urban expansion patterns,based on the intensity index of the urban expansion,the differentiation index of the urban expansion,the fractal dimension index,the land urbanization rate,and the center of gravity model,by taking the {1.-Tianjin-Hebei(Jing-Jin-Ji)urban agglomeration as an *** then build the center of gravity-{2.ally and temporally weighted regression(GTWR)model by coupling the center of gravity model with the GTWR *** the analysis of the temporal and spatial patterns and by using the center of gravity-GTWR model,we analyze the driving forces of the urban land expansion and summarize the dominant development modes and core driving forces of the Jing-Jin-Ji urban *** results show that:1.Between 1.90 and 2.1.,the expansion intensity of the Jing-Jin-Ji urban agglomeration showed a down-up-down trend,and the peak period was in *** 2.05,high-speed development took place in {1.,Tianjin,Baoding,and Langfang;after 2.05,rapid development was seen in Xingtai and Handan.2.Although the barycenter of cities in the Jing-Jin-Ji urban agglomeration has shown a divergent trend,the local interaction between cities has been enhanced,and the driving forces of urban land expansion have shown a characteristic of spatial spillover.3)The spatial development mode of the Jing-Jin-Ji urban agglomeration has changed from a dual-core development mode to a multi-core development mode,which is made up of three functional cores:the transportation core in the northern part,the economic development core in the central part,and the investment core in the southern *** synergistic development between each functional core has led to the multi-core development mode.4)The center of gravity-GTWR model combines the analy

关键词： urban land expansion driving forces center of gravity geographically and temporally weighted regression Jing-Jin-Ji

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