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Effect of ground cover changes on solar radiation absorption in Three Northeastern Provinces of China
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作者 SHUAI Yanmin CHEN Yangyang +3 位作者 SHAO Congying TIAN Yanjun QU Ge HUANG Jiapeng 《地球环境学报》 CSCD 2024年第4期675-690,共16页
Background,aim,and scope Solar radiation is the main source of energy for terrestrial ecosystems.Small changes in the absorption of solar radiation at the ground surface can have a significant impact on the climatic e... Background,aim,and scope Solar radiation is the main source of energy for terrestrial ecosystems.Small changes in the absorption of solar radiation at the ground surface can have a significant impact on the climatic environment.Natural and anthropogenic changes in ground cover are important factors affecting the absorption of solar radiation at the ground surface.This phenomenon is particularly pronounced in the mid and high latitudes.In order to quantify the inf luence of surface cover change on the absorption of solar radiation at the surface and to provide a scientific basis for changes in the climatic environment,this paper analyzed ground cover change,ground absorbed solar radiation change and the effect of ground cover change on ground absorbed solar radiation in the Three Northeastern Provinces of China from 2001 to 2018.Materials and methods In this study,the Three Northeastern Provinces of China were used as the study area.Firstly,satellite remote sensing data were used to obtain land cover data and albedo data for Aug.1st of each year in 2001,2005,2010,2015 and 2018.The albedo data were further used to calculate the absorbed solar radiation data at the ground surface.Next,the land cover data were used to count the area changes and shifts of different land classes over the five-year period.The land cover data were overlaid with the surface absorbed solar radiation data to obtain the mean and standard deviation of radiation absorption for different ground classes.The surface absorbed solar radiation data were subtracted to obtain the changes in surface absorbed solar radiation for 2001-2005,2005-2010,2010-2015 and 2015-2018.Ultimately,we used a combination of shifted changes in ground classes and changes in surface absorbed solar radiation data,with unchanged ground classes as a baseline and data such as slope orientation as an aid.We analyzed the effect of ground cover change on surface absorbed solar radiation at regional and pixel point scales.Results(1)The area of woodland and waters in the Three Northeastern Provinces of China increased and then decreased from 2001 to 2018,with an overall increase of 3.96%and 10.51%respectively.Cropland decreased and then increased,with a total decrease of 1.22%.Grassland continued to decrease,with an overall decrease of 19.36%.Building sites increased all the time,with a total increase of 11.08%.The main types of ground cover shifted were woodland,cropland and grassland.The main factors for the change in ground cover were China’s woodland protection policy and the saturation of the total woodland stock.(2)The five ground types absorb solar radiation in the order of waters>building sites>woodland>grassland>cropland.The surface absorption of solar radiation in the Songnen Plain,the Sanjiang Plain and the Songhua River Basin flowing through the Songnen Plain and the Sanjiang Plain varies significantly,by more than 25 W·m^(-2).(3)Changes in the ground cover type affected the absorption of solar radiation energy by the ground surface.There was a clear trend of interconversion between waters and cropland/grassland,cropland and woodland/grassland.In particular,the conversion of waters to both cropland and grassland radiation absorption values decreased significantly,while the opposite increased.The absolute difference between waters and cropland was a maximum of -156.66 W·m^(-2)in 2010-2015,and between waters and grassland was a maximum of 102.36 W·m^(-2) in 2005-2010.The radiative absorption values of woodland and grassland reclamation declined and conversely increased.The absolute difference between woodland and cropland was a maximum of-13.94 W·m^(-2) in 2010-2015 when woodland converted to cropland,and between grassland and cropland was a maximum of 22.36 W·m^(-2) in 2001-2005 when cropland converted to grassland,respectively.Discussion Ground cover changes in the Three Northeastern Provinces of China from 2001-2018 were inextricably linked to natural factors and the inf luence of Chinese national policies.The main inf luencing factors were China’s woodland protection policy,restoration of woodland fire sites,saturation of total woodland,optimization of cropland patterns,sanding of grassland,expansion of water conservancy projects,and urbanization expansion.There were differences in the radiation absorption characteristics of different ground cover types.This was due to the nature of the ground type itself and the regional environment.When ground cover types changed,their ability to absorb solar radiation also changed.The degree of change could be inf luenced by different ground types and different environmental factors.Different spatial scales can also produce variability.We need to consider the effects of ground cover change on the absorption of solar radiation at the surface in an integrated and comprehensive way.Conclusions The Three Northeastern Provinces of China had frequent changes in ground cover from 2001-2018,with the area of grassland decreased by almost 20%.These changes were due to natural environmental change and policies issued by China since the 21st century.The extent to which solar radiation was absorbed by different ground cover types was different,with grassland being the strongest and cropland the least.In the past few years,the Songnen Plain and Sanjiang Plain regions were the most significant changes in the absorption of solar radiation by the ground cover.The change in ground cover type led to a change in solar radiation absorption at the ground surface,with the conversion of waters to cropland or grassland and the conversion of cropland to woodland or grassland showing the greatest change in radiation absorption values,and vice versa.Of these,the absolute difference in the conversion of waters to cropland amounts to-156.66 W·m^(-2) in 2010-2015.The variation in the absorption of solar radiation at the ground surface was related to the characteristics of the ground class itself,but was also limited by the regional environment.Recommendations and perspectives This study showed that surface cover change can affect the absorption of solar radiation at the surface to varying degrees.The unchanged land classes were used as a comparative analysis in this paper,and it was clear from the paper that some of the unchanged land classes showed significant changes in radiation absorption that should be of interest in future studies. 展开更多
关键词 land surface cover changes surface absorption of solar radiation the Three Northeastern provinces ALBEDO
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Spatiotemporal Differences and Classification Regulation of Urbanization Impact on Agricultural Development in Shrinking Areas:A Case Study of 15 Shrinking Cities in Three Provinces of Northeast China
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作者 CHEN Xiaohong LIU Haihan +4 位作者 AN Yongle DAI Yue PAN Wei WANG Ying TANG We 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1053-1067,共15页
Studying the impact of urbanization on agricultural development in shrinking areas is important for maintaining food security and promoted agricultural development in China.Based on the measurement results of the shri... Studying the impact of urbanization on agricultural development in shrinking areas is important for maintaining food security and promoted agricultural development in China.Based on the measurement results of the shrinking cities in the three provinces of Northeast China,this paper selects 15 shrinking cities as the research object,and constructs a multi-dimensional index system to explore the impact of the urbanization level of the shrinking areas on the agricultural development in the region since 2007–2019,analyzes the influencing factors and their differences by using the geographically-weighted regression model and Geodetector,and proposes a targeted regulation strategy.The results show that:1)overall,there is a negative correlation between the urbanization level and the agricultural development level in the contracted areas of the three northeastern provinces.The urbanization level in these areas has a certain negative impact on the overall level of agricultural development;2)regarding the time dimension,the impact of urbanization level on the agricultural development level in the contracted areas of the three northeastern provinces gradually increases over time;3)regarding the spatial pattern,the overall impact of shrinking urbanization levels in the three provinces of Northeast China on the agricultural development shows a significant distribution pattern of high in the east and low in the west;4)the total population and natural population growth rate at the end of the year were the main factors influencing a certain level of urbanization on agricultural development in the shrinking cities while population density and the urban fixed asset investment rate were the secondary factors;and 5)the main reasons why the level of agricultural development in different cities was affected by the level of urbanization were different.However,they can be categorized into areas of population loss and spatial construction,which can be further divided into area of population loss in the northeast,areas of negative population growth in the west,and areas of urban spatial change in the south.According to the causes of the impact,this paper adopted targeted regulation strategies and formulated relevant policies and solutions that cater to local conditions. 展开更多
关键词 URBANIZATION agricultural development classification and regulation shrinking cities three provinces of Northeast China
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Coordinated Development of Tourism Economy and Ecological Environment Coupling in Mountainous Provinces:A Case Study of Guizhou
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作者 WU Bingqin ZHANG Chengru 《Journal of Landscape Research》 2023年第4期57-61,共5页
The degree of coupling coordination can reflect the intensity of interaction between multiple-indicator system,and can characterize the harmonious and consistent degree of benign correlation between them.It is an effe... The degree of coupling coordination can reflect the intensity of interaction between multiple-indicator system,and can characterize the harmonious and consistent degree of benign correlation between them.It is an effective measurement method for analyzing the level of coordinated development of tourism economy and ecological environment coupling.Guizhou,a mountainous province,is taken as the research object in this paper.Using entropy method and coupling coordination model,the coordinated development level of tourism economy and ecological environment coupling during 2011-2020 is measured and analyzed,and the coordinated development strategies for the tourism economy and ecological environment coupling in Guizhou,a mountainous province,are proposed. 展开更多
关键词 Tourism economy Ecological environment Coupling coordination degree Mountainous province Guizhou Province
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Review on Drought Disasters in the Five Provinces of Northern China in 1920
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作者 王鑫宏 《Meteorological and Environmental Research》 CAS 2010年第4期87-91,共5页
This paper analyzed the severe drought that took place in the five provinces of Northern China in 1920.Study suggested that the severe damage caused by the drought was resulted from many reasons,such as certain specif... This paper analyzed the severe drought that took place in the five provinces of Northern China in 1920.Study suggested that the severe damage caused by the drought was resulted from many reasons,such as certain specific natural conditions,deterioration of ecological environment,malformations of the rural economy and turbulence of domestic politics.However,some new phenomena took shapes during this time disaster relief activity. 展开更多
关键词 1920 Five provinces in northern China DROUGHT Characteristics Cause of formation Disaster relief China
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A Microscopic and Nanoscale Understanding of the Formation of Gold Geochemical Provinces 被引量:5
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作者 YE Rong WANG Xueqiu ZHANG Bimin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第3期995-1003,共9页
Gold geochemical provinces in China were delineated through stream sediment or catchment sediment sampling in this study.Each gold geochemical province delineated by a threshold value of 2.5 ng/g covers an area of tho... Gold geochemical provinces in China were delineated through stream sediment or catchment sediment sampling in this study.Each gold geochemical province delineated by a threshold value of 2.5 ng/g covers an area of thousands of kilometers.It is a dilemma that geochemists traditionally thought that gold could not migrate for a long distance in rivers or streams to form a large-scale geochemical anomaly due to its chemical inertness and high specific density.The quantitative spectroscopic analysis and observations under a scanning electron microscope (SEM) indicate the presence of submicroscopic gold particles (〈5 μm in diameter) in large quantities,and observations under a Transmission Electron Microscopy (TEM) further suggest the presence of nanoscale gold particles (several tens of nanometre in diameter) in ores,rocks,soils and stream sediments.Particularly,submicroscopic and nanoscale gold particles less than 5 μm were only found in samples having a low gold content (〈10ng/g).This result shows that geochemical provinces,delineated by a threshold value of 2.5 ng/g,are formed by long-distance transport of ultrafine gold in streams.The findings may provide direct microscopic evidence for gold migration to form geochemical provinces. 展开更多
关键词 GOLD Geochemical provinces Formation Mechanism Microscopic particles nanoscaleparticles
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Study of Noble Metal Elements in Lower Cambrian Black Rock Series of Guizhou-Hunan Provinces, China 被引量:2
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作者 Li Shengrong Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083 Gao Zhenmin Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 《Journal of Earth Science》 SCIE CAS CSCD 1999年第1期93-96,共4页
Systematic analyses of noble metal elements in the Lower Cambrian black rock series of South China are reported. Correlations of w (Os)/ w (Ir), w (Au)/ w (Ir), w (Ag)/ w (Au), w (Pt+Pd)/ w (Os+R... Systematic analyses of noble metal elements in the Lower Cambrian black rock series of South China are reported. Correlations of w (Os)/ w (Ir), w (Au)/ w (Ir), w (Ag)/ w (Au), w (Pt+Pd)/ w (Os+Ru+Rh+Ir), relations of noble metal and platinum group element (PGE) distribution patterns reveal that the noble metals are not directly from extraterrestrial materials. Studying the data of 9 aspects, the authors conclude that the noble metals were mainly from ultramafic mafic igneous rocks and their enrichment in black rocks is mainly controlled by hydrothermal fluid. 展开更多
关键词 black shale Au Ag PGE Lower Cambrian Guizhou Hunan provinces China.
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Periodicities in the emplacement of large igneous provinces through the Phanerozoic:Relations to ocean chemistry and marine biodiversity evolution 被引量:8
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作者 Andreas Prokoph Hafida E1 Bilali Richard Ernst 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第3期263-276,共14页
Large igneous provinces (LIPs) are considered a relevant cause for mass extinctions of marine life throughout Earth's history. Their flood basalts and associated intrusions can cause significant release of SO4 and ... Large igneous provinces (LIPs) are considered a relevant cause for mass extinctions of marine life throughout Earth's history. Their flood basalts and associated intrusions can cause significant release of SO4 and CO2 and consequently, cause major environmental disruptions. Here, we reconstruct the long-term periodic pattern of LIP emplacement and its impact on ocean chemistry and biodiversity from δ34Ssulfate of the last 520 Ma under particular consideration of the preservation limits of LIP records. A combination of cross-wavelet and other time-series analysis methods has been applied to quantify a potential chain of linkage between LIP emplacement periodicity, geochemical changes and the Phanerozoic marine genera record. We suggest a mantle plume cyclicity represented by LIP volumes (V) of V= (350-770) × 103km3sin(27πt/ 170 Ma)+ (300-650)× 103 km3 sin(2πt/64.5 Ma + 2.3) for t= time in Ma. A shift from the 64.5 Ma to a weaker -28-35 Ma LIP cyclicity during the Jurassic contributes together with probably independent changes in the marine sulfur cycle to less ocean anoxia, and a general stabilization of ocean chemistry and increasing marine biodiversity throughout the last -135 Ma. The LIP cycle pattern is coherent with marine biodiversity fluctuations corresponding to a reduction of marine biodiversity of -120 genera/Ma at 600 x 103 km3 LIP eruption volume. The 62-65 Ma LIP cycle pattern as well as excursion in -34Ssulfate and marine genera reduction suggest a not-vet identified found LIP event at - 440-450 Ma. 展开更多
关键词 Large igneous provinces Wavelet transform Sulfur isotope Mantle plume Marine biodiversity Periodicity
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Time series analysis of mantle cycles Part Ⅱ:The geologic record in zircons, large igneous provinces and mantle lithosphere 被引量:1
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作者 Kent C. Condie Stephen J. Puetz 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1327-1336,共10页
Igneous and detrital zircons have six major U/Pb isotopic age peaks in common(2700 Ma,1875 Ma.1045 Ma,625 Ma,265 Ma and 90 Ma).For igneous rocks,each age peak is comprised of subpeaks with distinct geographic distribu... Igneous and detrital zircons have six major U/Pb isotopic age peaks in common(2700 Ma,1875 Ma.1045 Ma,625 Ma,265 Ma and 90 Ma).For igneous rocks,each age peak is comprised of subpeaks with distinct geographic distributions and a subpeak age range per age peak≤100 Myr.There are eight major LIP age peaks(found on≥10 crustal provinces)of which only four are in common to major detrital zircon age peaks(2715 Ma,1875 Ma,825 Ma,90 Ma).Of the whole-rock Re depletion ages,58%have correspo nding detrital zircon age peaks and 55%have corresponding LIP age peaks.Ten age pea ks are fou nd in common to igneous zircon,detrital zircon,LIP,and Re depletion age time series(3225 Ma,2875 Ma,2145 Ma,2085 Ma,1985 Ma,1785 Ma,1455 Ma,1175 Ma,825 Ma,and 90 Ma).and these are very robust peaks on a global scale as recorded in both crustal and mantle rocks.About 50%of the age peaks in each of these time series correspond to predicted peaks in a 94-Myr mantle cycle,including four of the ten peaks in common to all four time series(2875 Ma,1785 Ma,825 Ma and 90 Ma).Age peak widths and subpeak ranges per age peak suggest that mantle events responsible for age peaks are<100 Myr and many<50 Myr in duration.Age peak geographic distributions show three populations(≤1000 Ma,2500-1000 Ma,>2500 Ma),with the number of new provinces in which age peaks are represented decreasing with time within each population.The breaks between the populations(at 2.5 Ga and 1 Ga)fall near the onsets of two transitions in Earth history.The First Transition may represent a change from stagnant-lid tectonics into plate tectonics and the Second Transition,the onset of subduction of continental crust.The major factor controlling geographic distribution of age peaks is the changing locations of orogeny.Before^2 Ga,age subpeaks and peaks are housed in orogens within or around the edges of crustal provinces,mostly in accretionary orogens.but beginning at 1.9 Ga,collisional orogens become more important.The coincidence in duration between magmatic flare-ups in Phanerozoic arcs and duration of age subpeaks(10-30 Myr)is consiste nt with subpeaks representing periods of enhanced arcrelated magmatism.probably caused by increased subduction flux.The correlation of isotopic age peaks between time series supports a cause and effect relationship between mantle plume activity,continental magma production at convergent margins,and crustal deformation.Correlation of over half of the detrital zircon age peaks(and six of the nine major peaks)with Re depletion age peaks supports an interpretation of the zircon peaks as crustal growth rather than selective preservation peaks. 展开更多
关键词 Isotopic age PEAKS U/Pb zircon AGES Re depletion AGES Large IGNEOUS provinces Age peak correlation MANTLE cycles
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The Research on the Current Situation of English Interpreting Studies in Three Northeastern Provinces of China
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作者 刘璇 徐畔 《海外英语》 2015年第2期169-170,203,共3页
Since the Master of Translation and Interpreting has been established under the approval of the Academic Degrees Committee of the State Council and the Chinese Ministry of Education, translation discipline stepped int... Since the Master of Translation and Interpreting has been established under the approval of the Academic Degrees Committee of the State Council and the Chinese Ministry of Education, translation discipline stepped into a rapid development period in China as well as the research of interpreting studies. This paper aimed at providing a brief introduction of the current situation and existing problems of English interpreting studies in Three Northeastern Provinces of China under the comparative analysis of literature in CNKI China Academic Journal Network Publishing Database from 2004 to 2013. 展开更多
关键词 THREE NORTHEASTERN provinces of China ENGLISH INTERPRETING studies current SITUATION
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关联理论视角下来华游记The Provinces of Western China的汉译研究
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作者 杨军燕 何泠静 《英语广场(学术研究)》 2021年第18期40-42,共3页
英国传教士普鲁恩夫人于1906年撰写了来华游记The Provinces of Western China,记叙晚清时期作者及其家人在华西诸省的所见所闻,这一游记对于我们了解当时四川、重庆、云南、贵州等地的风土人情具有重要价值。目前国内外学者对The Provi... 英国传教士普鲁恩夫人于1906年撰写了来华游记The Provinces of Western China,记叙晚清时期作者及其家人在华西诸省的所见所闻,这一游记对于我们了解当时四川、重庆、云南、贵州等地的风土人情具有重要价值。目前国内外学者对The Provinces of Western China所做的翻译研究不多。因此,文章拟以关联理论为指导,从词汇、句子两个层面分析来华游记The Provinces of Western China中的汉译实例,从而总结关联理论,希望对来华游记汉译具有指导意义。 展开更多
关键词 关联理论 来华游记 The provinces of Western China 汉译研究
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The Forming Mechanisms of the Neoproterozoic Molartooth Carbonatites in North Anhui and Jiangsu Provinces
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作者 Zhihai Jia,Liwei Zhang School of Resources and Environmental Engineering,Hefei University of Technology,Hefei 230009,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期260-260,共1页
As a characteristic sedimentary type,molartooth carbonatites veins(MCV) can be found in almost all the Neoproterozoic carbonatite strata in the North Anhui and Jiangsu Provinces.But their forming mechanism is still an... As a characteristic sedimentary type,molartooth carbonatites veins(MCV) can be found in almost all the Neoproterozoic carbonatite strata in the North Anhui and Jiangsu Provinces.But their forming mechanism is still an enigma,and more than four incompatible forming hypotheses have been put forward according to the structures,mineral components and elements of the MCV.Though all the MCV with the similar shape 展开更多
关键词 molartooth CARBONATITES NEOPROTEROZOIC forming mechanism NORTH ANHUI and Jiangsu provinces
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ENVIRONMENTAL FEATURES AND WATERENVIRONMENTAL PROBLEMS IN THE CONTIGUOUSREGION OF JIANGSU,SHANGDONG,HENANAND ANHUI PROVINCES
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作者 季子修 于秀波 张琛 《Chinese Geographical Science》 SCIE CSCD 1999年第1期63-69,共7页
Owing to intensive human activities and the floods of the Huaihe River in historic peiod, the contiguous region of Jiangsu, Shandong, Henan and Anhui provinces is suffering from a variety of environmental problems and... Owing to intensive human activities and the floods of the Huaihe River in historic peiod, the contiguous region of Jiangsu, Shandong, Henan and Anhui provinces is suffering from a variety of environmental problems and naturaldisasters, of which water pollution and drought-flood disasters are most observable. Considering the special location andenvironmental status of the contiguous region, advices are proposed in the paper: perfecting trans-regional managementssystem of water environment incorporating basin management agencies in local government activities; strengthening cooperation of two agencies: water conservancy agency and environment protection agency; enhancing integrated control ofwater pollution and flood-drought disasters; taking the interests of the whole river into acount and paying attention to bothstorage and drainage; broadening sources of water supply and inceasing water delivery; controlling pollutant discharge,developing water saving production system. 展开更多
关键词 environmental problems drought and flood DISASTERS WATER pollution contiguous region of Jiangsu Shandong HENAN and ANHUI provinces
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Environmental Effects of Foreign Trade and Its Spatial Variations in Mid-eastern Provinces and Cities of China
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作者 JIN Xianfeng DONG Suocheng +4 位作者 LUO Lingjun LI Yu YUAN Chao SHU Kesheng CHEN Jiaquan 《Chinese Geographical Science》 SCIE CSCD 2012年第5期626-636,共11页
The studies on environmental effects of foreign trade and its spatial variations are helpful to design and implement environmental protection countermeasures.In order to eliminate the adverse effects of insufficient o... The studies on environmental effects of foreign trade and its spatial variations are helpful to design and implement environmental protection countermeasures.In order to eliminate the adverse effects of insufficient observation values on the accuracy of regression results and dynamic information quantity of fitting equation during empirical study,panel data of the mid-eastern provinces and cities of China from 1985 to 2007 were selected based on the adjustment of classical regression model in this paper.Panel unit root test and panel cointegration analysis method were applied to investigating the environmental effects of foreign trade and its spatial variations in the mid-eastern provinces and cities of China and its three groups divided by foreign trade dependence.The results show that all scale effects are positive,while all technical effects are negative and unable to counteract positive scale effects.Foreign trade development is regarded as an important cause for outstanding eco-environmental problems in the mid-eastern provinces and cities of China.Total effects and structural effects are significantly different among different groups because of spatial variations in environmental policies,export destinations,source of FDI,etc.Following the principle of′coordinating generality and considering differences comprehensively′,it is essential to issue a series of policies and countermeasures corresponding to differences in regional environmental effect of foreign trade,in order to coordinate the relationship between foreign trade development and eco-environment in each region. 展开更多
关键词 mid-eastern provinces and cities of China foreign trade environmental effect spatial variation cointegra-tion analysis
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Large Igneous Provinces, Their Giant Mafic Dyke Swarms, and Links to Metallogeny
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作者 Simon M.JOWITT Richard E.ERNST 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期193-194,共2页
Giant mafic dyke swarms are a key component of the feeder system of Large Igneous Provinces(LIPs),large volume(>0.1 Mkm;;frequently above>1 M km;),mainly mafic(-ultramafic)magmatic events of intraplate aff... Giant mafic dyke swarms are a key component of the feeder system of Large Igneous Provinces(LIPs),large volume(>0.1 Mkm;;frequently above>1 M km;),mainly mafic(-ultramafic)magmatic events of intraplate affinity. 展开更多
关键词 Their Giant Mafic Dyke Swarms and Links to Metallogeny Large Igneous provinces
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Efficient allocation of coal de-capacity quota among Chinese provinces:a zero-sum gains data envelopment model
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作者 Gang Ma Xu Li Jianping Zheng 《Chinese Journal of Population,Resources and Environment》 2019年第3期229-240,共12页
An efficient coal de-capacity quota allocation scheme is key for accelerating China's coal supplyside structure reform.This paper allocates the coal de-capacity quota from the perspective of efficiency to seek the... An efficient coal de-capacity quota allocation scheme is key for accelerating China's coal supplyside structure reform.This paper allocates the coal de-capacity quota from the perspective of efficiency to seek the optimal capacity allocation in each Chinese province.First,we estimate the coal capacity of 24 coal-producing provinces based on boundary production function model.According to the actual coal overcapacity in each province,we initially allocate the coal decapacity quota of reducing 0.8 billion tons among them.Then,we optimize the initial allocation plan by using the zero-sum gains data envelopment model(ZSG-DEA)considering backward coal capacity,coal economic output,and coal resource endowment of each province.The results indicate that:First,there is coal overcapacity all over China,and there are obvious differences among the provinces.Second,the optimal allocation results show that the large coal producing provinces,including Shanxi,Inter Mongolia,Shaanxi,etc.,need to undertake most of the coal decapacity tasks,while the old coal producing provinces in northeast and west China should undertake a heavier burden of coal de-capacity.Third,the“one-size fits-all”approach burdens the small coal producing provinces with reducing coal capacity,leading to a general low enthusiasm for coal de-capacity in these regions. 展开更多
关键词 Coal de-capacity ZSG-DEA model Chinese provinces quota allocation
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Advancing beyond May 1971: How Do We Deal with the Possibility of Complicated Dyke Geometries, Long-Lived Lips, and Contrasting Basement Geological Provinces?
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作者 David A.D.EVANS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期31-33,共3页
The iconic image of a giant radiating dyke swarm subsequently fragmented into three pieces via supercontinental breakup was produced by Paul May in1971(see next page).That figure presented a large part of
关键词 and Contrasting Basement Geological provinces Long-Lived Lips Advancing beyond May 1971 How Do We Deal with the Possibility of Complicated Dyke Geometries
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Assessing Livelihood Vulnerability to Salinity Intrusion and Climate Variability--A Case Study in Coastal Provinces of the Mekong River Delta of Vietnam
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作者 Nguyen Duy Can 《Journal of Environmental Science and Engineering(B)》 2019年第4期147-155,共9页
Both ST(Soc Trang)and KG(Kien Giang)are coastal provinces of the Mekong River Delta and are most vulnerable to saline intrusion and climate variability.In 2016,thousands of Hhs(Households)in these coastal provinces we... Both ST(Soc Trang)and KG(Kien Giang)are coastal provinces of the Mekong River Delta and are most vulnerable to saline intrusion and climate variability.In 2016,thousands of Hhs(Households)in these coastal provinces were at risk due to severe drought and saline intrusion.This study applied the LVI(Livelihood Vulnerability Index)to estimate saline intrusion vulnerability of those two provinces.Data on socio-demographics,livelihoods,health,social networks,physical,financial and natural resources,natural disasters and climate variability were collected from a survey of 298 Hhs.From these data,the LVI of each coastal province was calculated.Results show that the overall LVI of KG province is higher than that of ST province.The analysis revealed that this practical method can be applied in different circumstances of climate change and purposes. 展开更多
关键词 COASTAL provinces MEKONG River Delta LVI SALINE intrusion and climate variability
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Survey of Premarital Pregnancy In Seven Provinces
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《China Population Today》 1998年第3期15-16,共2页
SurveyofPremaritalPregnancyInSevenProvincesThereisanotableincreaseinpremaritalpregnancyinChina,accordingtoas... SurveyofPremaritalPregnancyInSevenProvincesThereisanotableincreaseinpremaritalpregnancyinChina,accordingtoasamplingsurveycond... 展开更多
关键词 SURVEY SEVEN In provinces PREGNANCY Premarital
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Benchmark Dose Estimation for Cadmium-Induced Renal Effects Based on a Large Sample Population from Five Chinese Provinces
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作者 KE Shen KE Qin Mei +6 位作者 JIA Wen Jing CHENG Xi Yu LI Hao ZHANG Jie Ying LUO Hui Fang HE Jin Sheng CHEN Zhi Nan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第5期383-387,共5页
A survey involving 6103 participants from five Chinese provinces was conducted to evaluate the threshold value of urinary cadmium (UCd) for renal dysfunction as benchmark dose low (BMDL). The urinary N-acetyl-13-D... A survey involving 6103 participants from five Chinese provinces was conducted to evaluate the threshold value of urinary cadmium (UCd) for renal dysfunction as benchmark dose low (BMDL). The urinary N-acetyl-13-D-glucosaminidase (UNAG) was chosen as an effect biomarker. The UCd BMDLs for UNAG ranged from 2.18μg/g creatinine (cr) to 4.26μg/g cr in the populations of different provinces. The selection of the sample population and area affect the evaluation of the BMDL. The reference level of UCd for renal effects was further evaluated based on the data of all 6103 subjects. With benchmark responses (BMR) of 10%/5%, the overall UCd BMDLs for males in the total population were 3.73/2.08 μg/g cr. The BMD was slightly lower in females, thereby indicating that females may be relatively more sensitive to Cd exposure than are males. 展开更多
关键词 Benchmark Dose Estimation for Cadmium-Induced Renal Effects Based on a Large Sample Population from Five Chinese provinces BMD Cd
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Neoarchaean-Palaeoproterozoic Mafic Dyke Swarms from the Singhbhum Granite Complex,Singhbhum Craton,Eastern India:Implications for Identification of Large Igneous Provinces and Their Possible Continuation on Other Formerly Adjacent Crustal Blocks
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作者 Rajesh K.Srivastava Ulf Soderlund +2 位作者 Richard E.Ernst Sisir K.Mondal Amiya K.Samal 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期17-18,共2页
The Singhbhum craton of the eastern India consists of the Singhbhum Granite Complex(SGC)and the Chotanagpur Gneissic Complex(CGC)separated by the Singhbhum Mobile Belt(SMB).The CGC is intruded by Mesoproterozoic as we... The Singhbhum craton of the eastern India consists of the Singhbhum Granite Complex(SGC)and the Chotanagpur Gneissic Complex(CGC)separated by the Singhbhum Mobile Belt(SMB).The CGC is intruded by Mesoproterozoic as well as Cretaceous mafic dykes;in 展开更多
关键词 In Implications for Identification of Large Igneous provinces and Their Possible Continuation on Other Formerly Adjacent Crustal Blocks Neoarchaean-Palaeoproterozoic Mafic Dyke Swarms from the Singhbhum Granite Complex Eastern India
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