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7篇 您的检索式:作者名="Yaochen QIN"
    题名 作者 年代 出处 被引量
1The spatio-temporal variations of frost-free period in China from 1951 to 2012显示文摘The frost-free period(FFP)first frost date(FFD) and last frost date(LFD) have been regard as the important climate variables for agricultural production. Understanding the spatio-temporal variations of the FFPFFD and LFD is beneficial to reduce the harmful impacts of climate change on agricultural production and enhance the agricultural adaptation. This study examined daily minimum temperatures for 823 national-level meteorological stationscalculated the values of FFDLFD and FFP for station-specific and region-specific from 1951 to 2012estimated the gradients of linear regression for station-specific moving averages of FFDLFD and FFPand assessed station-specific time series of FFP and detected the abrupt change. The results as follows: at both the station level and the regional levelthe FFP across China decreases with the increase of latitude from south to northand with the increase of altitude from east to west generally. At the station levelthe inter-annual fluctuations of FFDLFD and FFP in south and west agricultural regions are greater than those in north and east. At the regional levelexcluding the QT regiontemporal changes of FFP are relatively small in both the low-latitude and the high-latitude regionsbut for the mid-latitude regions. According to the linear trend gradients of the moving average values of station-specific FFDLFD and FFPFFD was delayedLFD advancedand FFP extended gradually over the 80% of China. Furthermorethe change magnitudes for FFDLFD and FFP in the north and east agricultural regions are higher than that in the southern and western. Among the 659 station-specific time series of FFP examined by the Mann-Kendall test341 stationslocated mainly in the north regionhave one identifiable and significant abrupt change. And at the 341 stations with identified abrupt changesmost(57%) abrupt changes occurred during 1991–2012followed by the periods of 1981–1990(28%)1971–1980(12%)and 1951–1970(3%). The spatio-temporal variations of FFDLFD and FFP would provide important guidance to agricultural practices.NING Xiaoju LIU Gangjun ZHANG Lijun QIN Xiaoyang ZHOU Shenghui QIN Yaochen 2017Journal of Geographical Sciences2017,27,1:2
2The relationships between urban-rural temperature difference and vegetation in eight cities of the Great Plains显示文摘Interpreting the relationship between urban heat island (UHI) and urban vegetation is a basis for understanding the impacts of underlying surfaces on UHL The calculation of UHI intensity (UHII) requires observations from paired stations in both urban and rural areas.Due to the limited number of paired meteorological stations,many studies have used remotely sensed land surface temperature,but these time-series land surface temperature data are often heavily affected by cloud cover and other factors.These factors,together with the algorithm for inversion of land surface temperature,lead to accuracy problems in detecting the UHII,especially in cities with weak UHII.Based on meteorological observations from the Oklahoma Mesonet,a world-class network,we quantified the UHII and trends in eight cities of the Great Plains,USA,where data from at least one pair of urban and rural meteorological stations were available.We examined the changes and variability in urban temperature,UHII,vegetation condition (as measured by enhanced vegetation index,EVI),and evapotranspiration (ET).We found that both UHI and urban cold islands (UCI) occurred among the eight cities during 2000-2014 (as measured by impervious surface area).Unlike what is generally considered,UHII in only three cities significantly decreased as EVI and ET increased (p < 0.1),indicating that the UHI or UCI cannot be completely explained simply from the perspective of the underlying surface.Increased vegetative cover (signaled by EVI) can increase ET,and thereby effectively mitigate the UHI.Each study station clearly showed that the underlying surface or vegetation affects urban-rural temperature,and that these factors should be considered during analysis of the UHI effect over time.Yaoping CUI Xiangming XIAO Russell B DOUGHTY Yaochen QIN Sujie LIU Nan LI Guosong ZHAO Jinwei DONG 2019Frontiers of Earth Science2019,13,2:2
3Multi-scale integrated assessment of urban energy use and CO_2 emissions显示文摘Accurate and detailed accounting of energy-induced carbon dioxide(CO2) emissions is crucial to the evaluation of pressures on natural resources and the environment, as well as to the assignment of responsibility for emission reductions. However, previous emission inventories were usually production- or consumption-based accounting, and few studies have comprehensively documented the linkages among socio-economic activities and external transaction in urban areas. Therefore, we address this gap in proposing an analytical framework and accounting system with three dimensions of boundaries to comprehensively assess urban energy use and related CO2 emissions. The analytical framework depicted the input, transformation, transfer and discharge process of the carbon-based(fossil) energy flows through the complex urban ecosystems, and defined the accounting scopes and boundaries on the strength of ‘carbon footprint' and ‘urban metabolism'. The accounting system highlighted the assessment for the transfer and discharge of socio-economic subsystems with different spatial boundaries. Three kinds methods applied to Beijing City explicitly exhibited the accounting characteristics. Our research firstly suggests that urban carbon-based energy metabolism can be used to analyze the process and structure of urban energy consumption and CO2 emissions. Secondly, three kinds of accounting methods use different benchmarks to estimate urban energy use and CO2 emissions with their distinct strength and weakness. Thirdly, the empirical analysis in Beijing City demonstrate that the three kinds of methods are complementary and give different insights to discuss urban energy-induced CO2 emissions reduction. We deduce a conclusion that carbon reductions responsibility can be assigned in the light of production, consumption and shared responsibility based principles. Overall, from perspective of the industrial and energy restructuring and the residential lifestyle changes, our results shed new light on the analysis on the evolutionary mechanism and pattern of urban energy-induced CO2 emissions with the combination of three kinds of methods. And the spatial structure adjustment and technical progress provides further elements for consideration about the scenarios of change in urban energy use and CO2 emissions.ZHANG Lijun LIU Gangjun QIN Yaochen 2014Journal of Geographical Sciences2014,24,4:1
4A Theoretical Research on the System of Regional Development ModelsQIN Yaochen ZHAO Bingdong YUAN Zhongjin Henan University, Kaifeng 475001,P.R.China 1994Systems Science and Systems Engineering1994,4,3:0
5Regional Man-land System:Its Dynamics Characters,Structure and Evolutionary ModelsZHAO Bingdong QIN Yaochen ZHAO Qingliang Department of Geography, Henan University, Kaifeng 475001 1997Systems Science and Systems Engineering1997,7,3:0
6Geography's "World view": The ontological issues of geography显示文摘Contemporary science philosophy suggests that discussing ontological problems is of fundamental significance broadly within certain specific disciplines. Natural and social science research are inseparable from philosophical guidance; for instance, the philosophy of geography is the ideological basis for geography. The traditional philosophy of geography is methodology-oriented, which primarily emphasizes the 'logical structure of geography explanations,' and ignores the discussion of its ontology. This study, in the context of the philosophy of science, explores the relationships between methodology, ontology, and the philosophy of geography, defines the connotations of geographical ontology, analyzes the links and differences between philosophical ontology and scientific ontology of geography, clarifies the nature of geographical ontology, and summaries its theoretical values. The ontology of geography incorporates the philosophically ontological beliefs of geographers and geographical schools and the ontological commitment of the theory of geography. As different geographers hold different philosophical viewpoints, their ontological beliefs are different; one geographical theory asserts an ontological commitment of 'what is there,' which determines the nature and types of objectives the theory references. The ontological beliefs of geographers determine their epistemology, methodology, and axiology, and the ontological commitment of a geographical theory is the premise and basis of that theory.LIU Kai TANG Maolin LIU Rongzeng QIN Yaochen 2017Journal of Geographical Sciences2017,27,12:0
7Review on Quantitative Research Methods of Regional Sustainable Development in China显示文摘Since the 1990s, with the in-depth study and understanding of sustainable development, quantitative study of regional sustainable development (RSD) was increasingly hot in China. Based on quantitative study of RSD from Core Periodical in China National Knowledge Infrastructure (1992–2008), statistical analysis on the annual distribution, periodicals distribution and changes of the distribution were made. And from perspectives of social–economic, ecological, systematic and emerging methods, the course, problems and trends of the quantitative study methods on RSD were examined and analyzed to get a clear summary. By the review, the context on the quantitative study of RSD was to be clarified. The study also showed that, primarily, fields involving quantitative study are expanding; second, big progresses and constant development have been made on the systematic method gradually sophisticated, the flourishing ecological method and emerging new methods in the context of cross and integration which has made complex integrated systems a more satisfactory solution; third, the method system has been more multi-angled, and the clues of independent innovation have been observed despite the fact that the introduction of imported method is the main trend. Although many problems exist, multi-scale study, dynamic timeseries study and inter-regional comparative study will be further exploited and increasingly carried out with the progress of spatial information technology, which would boost the development and application of new methods in RSD study.Zhang Jinping Qin Yaochen Zhang Erxun 2010Chinese Journal of Population,Resources and Environment2010,8,3:0
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