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Ecological restoration for sustainable development in China

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National Science Review 2023年第7期10卷 60-71页

作者： Bojie Fu yanxu liu Michael E.Meadows State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical Science Beijing Normal University School of Geographic and Oceanographic Sciences Nanjing University College of Geography and Environmental Sciences Zhejiang Normal University Department of Environmental and Geographical Science University of Cape Town

Facing the need for transdisciplinary research to promote ecological restoration that achieves both social and ecological benefits,research on past restoration efforts that have directly or indirectly contributed to regional or national sustainable development warrants *** China as an example,in this review,we address three basic research questions that can be summarized as follows:ecological restoration—of what,for whom and to what purpose?Accordingly,a landscape pattern—ecosystem service—sustainable development’ co-evolutionary framework is proposed here to describe landscape-scale ecological restoration and its impact on landscape patterns and ecological processes,ecosystem services for human well-being,sustainable livelihoods and socioeconomic *** the strategic pattern of national ecological security to the pattern of major projects to protect and restore major national ecosystems,the spatial pattern of China’ s ecological restoration is more geographically *** major function-oriented zoning to systematic ecological protection and restoration,and for the purpose of achieving the Beautiful China Initiative,there are three stages of ecosystem services management:classification,synergy and integration,*** difference in geographic processes should be considered in the key re quirements of ecological restoration for China’ s five national strategies for regional sustainable-development *** understanding of the relationship between humans and nature in different geographical contexts is a scientific prerequisite to support policymaking related to ecological *** promote greater harmony between humans and nature,we propose four important research directions:(ⅰ) understanding coupling processes among key components,(ⅱ) identifying ecosystem service flows,(ⅲ) evaluating social-ecological benefits and(ⅳ) supporting adaptive management for regional sustainable development.

关键词： social-ecological system landscape pattern ecological process ecosystem services sustainable livelihoods policymaking

Dynamic Analysis of Geared Rotor System with Hybrid Uncertainties

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CHINESE JOURNAL OF MECHANICAL ENGINEERING 2024年第1期37卷 1-10页

作者： Feng, Wei Wu, Luji liu, yanxu liu, Baoguo liu, Zongyao Zhang, Kun Henan Univ Technol Henan Key Lab Super Hard Abras Grinding Equipment Zhengzhou 450001 Peoples R China Zheng Zhou Res Inst Mech Engn CO LTD Zhengzhou 450001 Peoples R China Tongji Univ Sch Mech Engn Shanghai 200092 Peoples R China

Current research on the dynamics and vibrations of geared rotor systems primarily focuses on deterministic models. However, uncertainties inevitably exist in the gear system, which cause uncertainties in system parameters and subsequently influence the accurate evaluation of system dynamic behavior. In this study, a dynamic model of a geared rotor system with mixed parameters and model uncertainties is proposed. Initially, the dynamic model of the geared rotor-bearing system with deterministic parameters is established using a finite element method. Subsequently, a nonparametric method is introduced to model the hybrid uncertainties in the dynamic model. Deviation coefficients and dispersion parameters are used to reflect the levels of parameter and model uncertainty. For example, the study evaluates the effects of uncertain bearing and mesh stiffness on the vibration responses of a geared rotor system. The results demonstrate that the influence of uncertainty varies among different model types. Model uncertainties have a more significant than parametric uncertainties, whereas hybrid uncertainties increase the nonlinearities and complexities of the system's dynamic responses. These findings provide valuable insights into understanding the dynamic behavior of geared system with hybrid uncertainties.

关键词： Geared rotor system Dynamic response Hybrid uncertainty Nonparametric modeling

Balancing Carbon Emission Reductions and Social Economic Development for Sustainable Development: Experience from 24 Countries

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Chinese Geographical Science 2020年第3期30卷 379-396页

作者： KANG Meimei ZHAO Wenwu JIA Lizhi liu yanxu State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal Univer-sityBeijing 100875China Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

The impact of human carbon emissions on climate has generated widespread global concern. We selected 24 countries as research objects and analysed the changes in carbon emissions in different countries between the establishment of emission reduction actions in 1990 and 2014. Then, we selected 19 factors representing four categories(economy, population, technology and energy) to explore the key factors that led to changes in carbon dioxide(CO2) emissions in different countries. Emission reduction actions since 1990 did not lead to marked improvements, and only five countries(Russia, Germany, the United Kingdom, Italy and France) achieved reductions in carbon emissions. The factors that influenced CO2 emissions varied among countries. In most developing countries, reductions in CO2 emissions were caused by reductions in poverty and inherent natural conditions. Moreover, the extent of influence of a given factor on CO2 emissions differed among countries. The global economic crisis may cause similar fluctuations in CO2 emissions in many countries. Adjustments to energy and industrial structures are the main reason for the reduction in carbon emissions, whereas economic growth and urbanization are the two major contributors to the growth of carbon emissions. According to historical carbon emissions data, a green energy revolution must be implemented to address global climate change and ensure the sustainable development of human societies.

关键词： carbon dioxide(CO2)emissions climate change economic growth sustainable development

New Developments and Perspectives in Physical Geography in China

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Chinese Geographical Science 2019年第3期29卷 363-371页

作者： FU Bojie TIAN Tao liu yanxu ZHAO Wenwu State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical Science Beijing Normal University

Physical geography is the cornerstone of geography. In this article, the starting points of disciplines in physical geography in recent years in China are discussed. With the coupling of systems set as the research object, and sustainable development as the ultimate goal, the upgrade of physical geography can be deconstructed into three steps: deepen physical geography from the perspective of pattern-process coupling, improve the focus of physical geography from ecosystem processes to ecosystem services, and increase the understanding of the physical geography ‘pattern, process, service, sustainability' research cascade. The incorporation of human activities into physical geographic processes is essential to conduct integrated analysis on physical and human factors at different scales. The development of ecosystem service models that couple supply-demand and sustainable development are of great importance to bridge the role of ecosystem services between the natural environment and human well-being. Moreover, human-land systems and sustainable development have become the core areas and frontiers of integrated physical geography and even geography in general. China faces the great strategic demand of constructing an ecological civilization in a new era, and the development of the disciplines of physical geography should give full access to the advantages of intersecting and comprehensive disciplines, focus on the human-land system patterns,processes, and services in key research areas, and provide disciplinary support for regional, national, and global sustainable development.

关键词： pattern-process coupling ecosystem services sustainability human-land system China’s national demands

Hydrocarbon Exploration in the South Yellow Sea Based on Airborne Gravity,China

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Journal of Earth Science 2016年第4期27卷 686-698页

作者： Wenyong Li yanxu liu Bing Li Feng Luo China Aero Geophysical Survey&Remote Sensing Center for Land and Resources Beijing 100083China

Differences between the Cenozoic and pre-Cenozoic strata and structures in the middlesouth South Yellow Sea are analyzed using high-resolution airborne gravity data combined with data from offshore wells, seismic exploration and the regional geological background, using forward and inverse methods. We discuss why hydrocarbon exploration has so far failed in the South Yellow Sea, and put forward alternative future exploration plans. The results show that there are thick Cenozoic strata over Jurassic-Cretaceous continental strata in the southern basin of the South Yellow Sea, contrasted with thick Mid-Paleozoic marine strata preserved in the middle uplift area. In the mid-southern South Yellow Sea, airborne Bouguer gravity anomalies are fragmentized with scattered local anomalies. Many tensile normal faults and minor fault blocks occur in the Cenozoic strata. In contrast, reverse faults and nappe structures are found in pre-Cenozoic strata. The essential reasons for the lack of a breakthrough in hydrocarbon exploration are the complexity of geological structures, hydrocarbon accumulation environments, seismic-geologic conditions, and the difficulty of interpreting and understanding these features, rather than an imbalance of exploration framework. Hydrocarbon exploration should be targeted at Mid-Cenozoic continental strata, especially of Paleogene age, in the middle to southern parts of the South Yellow Sea. Special attention should be paid to the favorable structural belts SYI1, SYI2, SYI3 and SYI4 in the southern basin of the South Yellow Sea, where detailed seismic exploration or drilling should be carried out. Attention should also be given to Mid-Paleozoic marine strata in the middle uplift area of the South Yellow Sea. Key strategies that could lead to a hydrocarbon exploration breakthrough are improving exploration resolution, conducting detailed studies of fine structures, and accurately locating minor structures.

关键词： airborne gravity strata and structures hydrocarbon exploration Paleogene SouthYellow Sea.

Study of Residual Basin and Tectonolayering Based on Airborne Gravity and Magnetic Data

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Acta Geologica Sinica(English Edition) 2013年第4期87卷 1137-1153页

作者： LI Wenyong ZHOU Jianxin XIONG Shengqing liu yanxu XU Jianchun China Aero Geophysical Survey and Remote Sensing Center for Land and Resources

This paper takes the South Yellow Sea as an example to show a new method for comprehensive geological-geophysical research such as residual basin and tectonolayering using airborne gravity and magnetic data in China. Based on airborne gravity and magnetic data, by measuring and analyzing stratigraphic density and susceptibility, the depths to the pre-Sinian magnetic basement top, the pre-Jurassic top and the Cenozoic bottom, are obtained by forward and inverse methods constrained by seismic and drilling data; and furthermore, the residual thicknesses of the Sinian-Triassic, the Jurassic-Cretaceous and the Cenozoic are calculated. Based on airborne gravity and magnetic anomalies, the faults in the pre-Sinian magnetic basement, the Jurassic-Cretaceous and the Cenozoic are respectively interpreted by the qualitative and quantitative methods. On the basis of the above study, and combining regional important tectonic events, four tectonolayers are divided in the vertical succession in South Yellow Sea, namely the pre-Sinian magnetic basement, the Sinian-Triassic, the Jurassic-Cretaceous and the Cenozoic. The result shows that there are thick Cenozoic and Jurassic-Cretaceous strata and thin residual Sinian-Triassic strata in the Suzhong-Huangnan depression area, but there are thin or only sporadic Mesozoic-Cenozoic terrestrial strata and thick Sinian-Triassic marine strata reserved in Subei-Huangzhong uplift area and Sunan-Wunansha uplift area. The four tectonolayers are very different in structures as well as distributions in plane.

关键词： airborne gravity and magnetics comprehensive interpretation residual basin,tectonolayering South Yellow Sea

Superimposed versus residual basin:The North Yellow Sea Basin

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Geoscience Frontiers 2012年第1期3卷 33-39页

作者： Wenyong Li Wenfen Lu yanxu liu Jianchun Xu China Aero Geophysical Survey and Remote Sensing Center for Land and Resources Beijing 100083China

The North Yellow Sea Basin is a Mesozoic and Cenozoic basin. Based on basin-margin facies, sedimentary thinning, size and shape of the basin and vitrinite reflectance, North Yellow Sea Basin is not a residual basin. Analysis of the development of the basin＇s three structural layers, self-contained petroleum systems, boundary fault activity, migration of the Mesozoic--Cenozoic sedimentation centers, different basin structures formed during different periods, and superposition of a two-stage extended basin and one-stage depression basin, the North Yellow Sea Basin is recognized as a superimposed basin.

关键词： Superimposed basin Residual basin Identification method Basinal structures Basin superposition North Yellow Sea Basin

Study on the Flow of Rural Labor Force and the Contribution of Terrain Factor in Shaanxi,China

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Chinese Journal of Population,Resources and Environment 2012年第4期10卷 77-83页

作者： liu yanxu Li Chunyue Ren Zhiyuan College of Tourism and Environment Sciences Shaanxi Normal University Northwest Land and Resources Research Center Shaanxi Normal University

The flow of rural labor to urban is a significant phenomenon in China during the last 20 *** spite of many researches focus on the driving force of economy,terrain is an important index in the rural *** is a question that whether the flow of rural labor has some relationships with *** study used the relief degree of land surface (RDLS) as terrain index,and the cost distance model and the center of gravity model to analyze the relationship between terrain and labor *** results indicated:(1) In the last 20 years,the rural labor force was not simply flowing to the low terrain region in Shaanxi *** the RDLS was constantly strengthening the influence on the movement.(2) The RDLS was low in Guanzhong region,and the translation of rural labors relatively was not *** North Shaanxi act as the energy industry base,the number of rural labors there increased faster than in South Shaanxi.(3) The movements of economical centers took an important role in the change of rural labor centers,and terrain factors also showed a high correlation with *** is found that the lower of the terrain index,the higher of the land intensive degree,the more intensive of nonagriculturalization process.

关键词： rural labor force relief degree of land surface center of gravity spatio-temporal pattems

Using Impervious Surfaces to Detect Urban Expansion in Beijing of China in 2000s

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Chinese Geographical Science 2016年第2期26卷 229-243页

作者： PENG Jian liu yanxu SHEN Hong XIE Pan HU Xiaoxu WANG Yanglin Laboratory for Earth Surface Processes Ministry of Education College of Urban and Environmental Sciences Peking University

The change of impervious surface area(ISA) can effectively reveal the gradual process of urbanization and act as a key index for monitoring urban expansion. Experiencing rapid growth of the built environment in the 2000 s, urban expansion of Beijing has not been fully characterized through ISA. In this study, Landsat TM images of Beijing in 2001 and 2009 were obtained, and the eight-year urban expansion process in Beijing was analyzed using the ISA extracted by means of the vegetation-imperious surface-soil(V-I-S) model. From the spatial variation in ISA, the ring structure of urban expansion in Beijing was significant during the study period, with decreasing urban density from the city center to the periphery. In the ring road analysis, the most dramatic changes of ISA were found between the fifth ring and the sixth ring. This area has experienced the most new residential development, and is currently the main source of urban expansion. The typical profile lines revealed the directional characteristics of urban expansion. The east-west profile was the most urbanized axes in Beijing, while ISA change in the east-north profile was more significant than in the other five profiles. Moreover, the transition matrix of ISA levels revealed an increase in urban density in the low density built areas; the Moran′s I index showed a clear expansion of the central urban area, which spread contiguously; and the standard deviational ellipse indicated the northeast was the dominant direction of urban expansion. These findings can provide important spatial control guidelines in the next round of national economic and social development planning, overall urban and rural planning, and land use planning.

关键词： impervious surface area(ISA) vegetation-imperious surface-soil(V-I-S) model profile line analysis urban expansion direction Beijing China