Archive

  • 2019 Volume 39 Issue 8
    Published: 10 August 2019
      

  • Select all
    |
  • Wang Ruoyu,Huang Xu,Xue Desheng,Liu Ye
    Download PDF ( ) HTML ( )   Knowledge map   Save

    Based on the national statistical yearbook data from 2005 to 2015, this article studies the spatial pattern evolvement of the distribution of scientific research talents in China (limited to data, the study area not includes Hong Kong, Macao and Taiwan) and its influence mechanism by applying panel negative binomial regression and spatial auto-correlation analysis. The result shows that: 1)The distribution of scientific research talents in China showed great imbalance. Generally speaking, talents agglomerate in the southeast but sparse in the northwest. Scientific research talents are mainly agglomerate in Beijing, Tianjin and Shanghai; 2) The distribution of scientific research talents has some spatial agglomeration characteristics. Hot spots are the eastern coastal areas, especially Beijing, Tianjin, Shanghai and Jiangsu while the cold point area is concentrated in the western region and Heilongjiang Province. The area of cold points has decreased from 2005 to 2015; 3) Talent policy, the development of universities and the level of public service are the main factors that determines the overall spatial distribution of scientific research talents, but no evidence support that other factors have significant influence. With the increase of professional qualification, the influence of the economic factors on the scientific research talent gets weaker, but the influence of public service level gets stronger. On the other hand, from the perspective of regional differences, compared with the western regions, the scientific research talents working in middle and eastern universities are more likely to be affected by the public service.

  • Li Xueming,Guo Yujie,Tian Shenzhen,Bai Zhizhen,Liu He
    Download PDF ( ) HTML ( )   Knowledge map   Save

    Coupling coordination within the human settlements system is the basis for ensuring a balanced development of the human settlements. This paper expounds the internal coordination of the human settlements system and discusses the spatial and temporal distribution and driving force of the coupling and coupling coordination degree of human settlements in Liaoning Province, China. This paper builds the evaluation index system of the coupled development of human settlements system based on the five subsystems of ‘human-living-support-nature-society’. The coupling model between two systems is extended to five subsystems of human settlements. The entropy method and GIS spatial analysis methods are used to analyze the spatial-temporal evolution characteristics of coupling coordination degree of human settlements system in Liaoning Province from 2005 to 2016. The research shows that: 1) From 2005 to 2016, the coupling degree and coupling coordination degree of the human settlements system in Liaoning Province showed a slow upward trend. There is a difference in the degree of coordination between cities. The high value areas of coupling coordination degree includes Shenyang and Dalian. The median area of coupling coordination degree includes Anshan, Fushun, Benxi, Dandong, Jinzhou, Yingkou, Liaoyang, Panjin, Tieling, Chaoyang and Huludao. The coupling coordination degree low value area includes Fuxin. 2) The coupling coordination degree of human settlements in Liaoning Province is in a dispersed pattern which presents a ‘roof ridge’ pattern and a ‘dual-core structure’ that decrease from the middle to the sides. In the east-west direction, the spatial evolution trend gradually evolves from the inverted the ‘U’ shape to the‘—’shape, and the north-south direction changes from the tilted line type to the ‘L’ type. The coupling coordination degree between Shenyang and Dalian has been in the top two, far higher than other cities, as a dual core to lead the coordinated development of the human settlements system in Liaoning Province. 3) There are five types of zones: medium coupling-low coordination zone, medium coupling-transition coordination degree zone, high coupling-low coordination degree zone, high coupling-transition coordination degree zone and high coupling-high coordination degree zone. 4) We use geographic detector to explore the driving forces of the coupiling coordination within the human settlements system. The spatial differentiation driving force mainly includes people's needs, economic development, housing and internet development. People's needs are the basis for the coordinated development of the human settlements system. Economic development is the main driving force, and housing is a tool for coordinated development. However, the development of the Internet is a new driving force for the coordinated development of the human settlements system.

  • Yuan Yuan,Zhang Xiaolin,Li Hongbo,Hu Xiaoliang
    Download PDF ( ) HTML ( )   Knowledge map   Save

    Recognition of rural space in western countries has undergone a profound turn from material and ideational space to the three-fold model of rural space proposed by Halfacree. Fundamentally influenced by “the production of space” and widely accepted as the systematic theoretical framework of rural space in western world, this model provides a whole new perspective on the transition of rural space in western countries from productivism to post-productivism. Differentiated rural space in western countries manifest that affected by interwoven forces of globalization, urbanization and modernization, dynamics and patterns of rural space transition development has been regenerated by combination and reorganization of essential productive factors, as well as its functions and values. Process of rural space transition in western countries reflects general rules in the view of “global countryside” proposed by Woods, which offers a great and significant enlightenment for studies in China. Based on the situation that urban and rural space is going through a critical period of accelerated reconstruction, theoretical guidance is urgently needed for newly emerging problems, patterns and forces, especially more studies on multi-dimensional cognition, multi-functional trend and multi-agent mechanism of rural space and its transition . In the end, this paper calls for establishing research paradigm of rural geography with Chinese characteristics, so as to better respond to the theme of the times on rural revitalization

  • Xu Liting,Yao Shimou,Chen Shuang,Xu Yu
    Download PDF ( ) HTML ( )   Knowledge map   Save

    Eco-city is an essential form of sustainable urban development and represents the tendency of modern cities. The evaluation of eco-city provides the fundamental basis for the planning, construction and management of eco-city. With the rapid development of social and economic, the connotation and evaluation index system of eco-city also need to update with the times. Currently, China's economy has shifted from a rapid growth stage to a high-quality development stage. Urban is an essential platform of regional economic development, it will also enter the stage of high-quality development. The eco-city is highly compatible with the concept of high-quality development, it is necessary to integrate the high-quality development ideology in the eco-city evaluation, which is in line with the current urban transformation and development requirements of China. Therefore, on the basis of combing the evolution and connotation development of eco-city, we set up an eco-city evaluation system guided by the concept of high-quality development, and then taking the Yangtze River Delta Urban Agglomeration (YRDUA) as an example to carry out the ecological level evaluation study of urban. Thus, the characteristics of spatial-temporal variations of urban ecological level was evaluated and the main obstacle factors was revealed. Based on various statistical data of YRDUA in 2005, 2010 and 2015, 27 indicators for evaluating eco-city that reflects the requirements for high quality development ideology were constructed from three aspects, they are economic development, ecological environment protection and social civilization progress. The entropy-TOPSIS model then analyzed the ecological level of cities, and the major obstacle factors was measured through obstacle degree model. The results showed that: The ecological level of the YRDUA present a steady improvement trend, the urban ecological level spatial pattern of the YRDUA shows a "core-periphery" structure, and it experienced the evolution process of double-high value center in 2005, single-high value center in 2010 and multiple-high value center in 2015. The ecological level of Shanghai municipality, provincial capital cities and other economically-strong cities like Suzhou and Wuxi are significantly better than other cities. There is a significant correlation between ecological level and city hierarchical, which means the urban ecological level is directly proportional to the population scale. The higher the urban hierarchy, the more advantageous the urban construction has, thus the higher the ecological level is. And the ecological level gap of the different urban hierarchy has gradually expanded during the study period. From the perspective of the 3 subsystems, economic development, ecological environment protection and social civilization progress, each city presents different advantages and disadvantages regarding different indicators. Moreover, the difference of ecology level regarding the economy and society are significant than the ecological environment. The obstacle factors of the ecological level of the YRDUA are relatively stable. For most cities, economic development, infrastructure, and public service factors are the primary constraints, especially in cities with relatively backward economic development, while a few economically developed cities have significant obstacles to environmental foundation and social civilization progress. In the future, the differentiated policies deserve much more attention, urban ecological level should promote to higher quality according to local conditions especially its significant constraints.

  • Wang Yingzhi,Wang Lijun
    Download PDF ( ) HTML ( )   Knowledge map   Save

    With the rapid progress of society and increase of motorization level, traffic accident is also increasing. It has become the third leading cause of accidental death in China, seriously threatening human life and social development. How to identify the black point of traffic accident is one of the important issues of traffic safety management. This article took the view of spatio-temporal street-network, matched traffic accidents to the spatial-temporal subsection of street-network for calculating the network spatio-temporal kernel density estimate. A method of identifying accident black points, which using street-network spatio-temporal kernel density estimated value as identification index and cumulative frequency analysis to determine the identification threshold, was proposed. We took the traffic accident records of a county in East China from 2013 to 2015 as the research data, to identify the traffic accident black points. It can be seen that traffic accidents have significant clustering characteristics in spatial road network and temporal features. In addition, most of the spatio-temporal sub-sections of accident black appear at roads intersections, which proves that there is indeed geometric heterogeneity between intersections and ordinary sections. The accident black points is a closed area formed by the continuous sub-sections of spatio-temporal with high accident rate. Moreover, the accident incidence rate in the center of the area must be higher than that in the surrounding area. In this study, the accident black points are displayed in 3d scene with 2d plane and temporal dimension. Further, the road characteristics, surrounding location and temporal characteristics of 8 high-risk accident black points are analyzed. The experiments demonstrated that this method can more accurately identify the spatio-temporal boundary of accident black points.

  • Zhu Huayou,Li Han,Dai Zejuan,Jiang Ziran
    Download PDF ( ) HTML ( )   Knowledge map   Save

    The relocalization of enterprises is the reaggregation after industrial transfer, which has a complex and profound influence on the economic society of aggregation area. However the validity about theoretical research guiding local economic development is insufficient, due to relatively lacking of measurement and research about the effects of enterprises re-localization and its influence on regional transformation and development. Based on the theoretical context of localization, delocalization and re-localization, this study proposes the measurement method of enterprises re-localization effects and the mechanism of regional transformation and development, and then takes the demonstration area of Wanjiang industry as the object, to analyze the spatial and temporal evolution characteristics of enterprises re-localization effect from outside MAR externalities, Jacobs externalities and Porter externalities. Finally, the two-way fixed effect model is used to verify its impact on the transformation and development of the Wanjiang demonstration area, and corresponding policy recommendations are put forward. The results shows that: 1) Time evolution characteristics are related to the industrial inheritance policies of different cities and the types of industries transferred; 2) MAR externalities presents the evolutionary characteristics of “overall equilibrium-westward enhancement-southward enhancement”, Jacobs externalities From southwest to northeast, the Porter externalities is enhanced in the space of dimensions; 3) The influence of MAR externalities on regional economic development level and regional innovation is inverted “U” type; Jacobs externalities has significant positive effect on regional economic development level, and its relationship with regional innovation is “U” type; Porter externalities has a positive effect on the regional economic development level and a significant negative effect on regional innovation.

  • Cao Linjian,Wang Jie,Wang Huanhuan,Cui Huihui
    Download PDF ( ) HTML ( )   Knowledge map   Save

    By introducing utility function into the analysis of push-pull theory and drawing lessons from existing research, this article builts the coupling-coordination model to analyze the coupling between infrastructure and population agglomeration in Beijing-Tianjin-Hebei region based on the improvement and integration of the system development model, coordination model, coupling model and relative degree of development model. And the inverted U-shaped relationship between urban infrastructure construction and population agglomeration is analyzed; a comprehensive index system covering 11 aspects and 31 indicators of urban infrastructure construction and population agglomeration is constructed; an empirical analysis of the evolution laws of the coupling between infrastructure construction and population agglomeration in Beijing, Tianjin and Hebei region from 2006 to 2016 is made and an in-depth analysis of the characteristics of comprehensive development index, coupling status and coordinated development stage between the two systems is also part of the research. The research results reveal that the development index and coupling degree of the two systems, infrastructure construction and population agglomeration, show similar trend of increase, and there exists a good foundation for the coordinated development and a great coupling driving potential in Beijing, Tianjin and Hebei Region; the system coupling is developing from antagonistic stage to high-level coupling stage; the systems mostly develop synchronously in time sequence, and the inter-regional coupling degree is basically realized; there are differences in spatial distribution of system coupling degree which has reached the top of the inverted U-shaped relationship. In the future, we should focus on avoiding the occurrence of“urban diseases” and do more research on the two systems from the dynamic perspective.

  • Chen Huiling,Wang Boli,Cao Xiaoshu,Shi Enming,Liu Yongwei
    Download PDF ( ) HTML ( )   Knowledge map   Save

    Rail transit provides the possibility for residents from car travel to public transport travel. This paper studies the changes and characteristics of travel costs which subway construction brought up and the spatial equity of its influence from two aspects of travel time and travel expenses. The results show that: 1) The spatial patterns of weighted average time and fare indicators are core-peripheral. After the operation of subways, the relative change value of the weighted time in the southern suburbs is high, and the change rate of Huadu district is the lowest. The areas of high change rate of weighted fare accessibility are concentrated in the southern fringe areas and along the subway lines. 2) In the bus transit scenario, the isotime curves of CBD are concentric circles and eighty percent of residents could arrive in the nearest commercial complex within 80 minutes and RMB 2. In the rail transit scenario, the isotime curves are extended and diffused along the subway lines and eighty percent of residents could arrive in the nearest commercial complex within 30 minutes and RMB 5. 3) Whether or not to take the subway, the inequity degree of travel time between communities is higher than of travel fare. The absolute and relative improvement of travel time of Panyu district after with subway is great. Due to the bus transit network is well in central city, the absolute change of travel time which subway brought is slight, but its relative change is high. The rail transit has a significant on the cost-effective of medium-distance and long-distance travel. This research could provide the theoretical support for the development of the multi-modal transit system.

  • Jiao Limin,Yang Ludi,Liu Jiafeng,Zhang Boen,Xu Gang
    Download PDF ( ) HTML ( )   Knowledge map   Save

    The urban spatial structure and its evolution have a deep impact on the development of urban spatial pattern. The traditional urban expansion simulation ignores the important influence of urban spatial structure information. This study uses Multi-order Landscape Expansion Index (MLEI), which measures spatial adjacency of new patch to identify characteristics of urban cluster, and puts such information into MLEI-CA Model. This paper uses MLEI-CA Model to simulate the urban expansion of Wuhan, based on the remote sensing image data of 1990, 2000 and 2013. Meanwhile, this paper verifies the applicability of such method by comparing with Logistic-CA model. The result shows that the MLEI-CA model can reveal the spatial evolution of urban expansion more accurately and has a better simulation accuracy than Logistic-CA model, especially in the Kappa coefficient and urban land use accuracy. The accuracy of MLEI-CA model increases by 6% and 4% respectively. The MLEI-CA model puts the information of urban spatial structure into consideration from the perspective of city expansion cluster. Furthermore, it provides new ideas for simulation of urban expansion. The simulation results can provide reference for urban planning and urban expansion effect analysis. In addition, the research model mentioned in this paper can provide new theoretical references and technical support for urban expansion simulation. However, deficiencies still exist in this study. For example, if an intelligent algorithm was considered into the model, a more realistic result might be gotten; This article use MLEI-CA model to simulate urban space form only on the basis of current situation. In practice, different situation can get different scenarios of urban space form. The MLEI-CA model needs more deep research in different cities.

  • Cheng Lisha,Wang Shijun,Yang Ran
    Download PDF ( ) HTML ( )   Knowledge map   Save

    With the progress of the Belt and Road Initiative and its construction, China's multifaceted cooperation with its neighbors has further deepened. Due to the special geographical location and unstable surrounding international environment, the geo-relations in Northeast China have always been complex and changeable, profoundly affecting the region's economic and social development. By combing the relevant historical documents, this paper analyzes the evolution process of the geo-relations in Northeast China since the 20th Century, and comprehensively depicts the influence of the geo-relations on the regional development.The main conclusions are as follows. From 1910s to 1940s, As a result of the outbreak of World War I and the establishment of the Soviet government, the alliance between Japan and Russia collapsed. The relationship between Japan and the United States hovered between competition and cooperation. Japan's colonial rule over the Northeast China changed the balance of the strategic situation of Northeast Asia. While the victory of the Anti-Fascist War and Counter-Japanese War basically broke the conspiracy of some countries to Northeast China. Overall, the geo-relations in Northeast China were semi-deformedly open, and the region was in a state of warlords chaos and Japanese colonial rule for a long time. At the same time, the Northeast China ushered in the peak of immigration, and the agricultural economy and national industry developed rapidly. However, the Japanese economy expanded willfully in the region, and a lot of resources and wealth were plundered. Since the founding of new China, Sino-Korean and Sino-Soviet relations have undergone a transition from the honeymoon period to the tortuous development period. Then the geo-relations in Northeast Asia show a relatively stable, peaceful and pluralistic trend of development, but there are still some challenges in the process of development, mainly coming from the United States and its military alliances and Korean Peninsula. Accordingly, the industrial development in the region has grown from prosperity to decline. And the region has made some progress in opening up regional cooperation towards Northeast Asia, among them, the implementation of Tumen River regional cooperation and development strategy and Belt and Road Initiative are the most representative. Nowadays, the geopolitical relationship in Northeast Asia is complicated, while the prospect of geo-economic cooperation is broad. In the future, we should vigorously promote the political and economic cooperation between Northeast Asian countries and sub regions, simultaneously improving the endogenous development power and the level of opening up to the outside world in Northeast China.

  • Li Ning,Li Tiebin,Fang Yangang,Zhou Lijun,Wang Yu,Zhao Wei
    Download PDF ( ) HTML ( )   Knowledge map   Save

    County economy is the important support of China's economic growth, while the promotion of total factor productivity has become the only way to promote the economic growth of the county. Based on 11-year panel data of 39 counties in Jilin Province, the article estimated the total factor productivity of the counties, using the DEA-Malmquist index method. And then, by means of the exploratory spatial data analysis (ESDA), the article made a further study on the spatial correlation and spatial difference of the economic development efficiency of the counties from different time dimensions. Research findings: 1) During the inspection period, the total factor productivity of county area in Jilin Province was generally rising, and the differences among counties showed the trend of expanding first and then narrowing. And there is no positive correlation between total factor productivity and county economic aggregate; 2) In terms of total factor productivity improvement, technological progress has played a dominant role, but in recent years, the contribution to total factor productivity has decreased year by year. While the promoting effect of technical efficiency and scale efficiency on the total factor productivity of Jilin Province is increasing year by year; 3) As far as the whole province is concerned, there is no significant global spatial autocorrelation in the total factor productivity of the counties, and the spatial pattern of random distribution is basically presented. However, in the local spatial scale, there is a certain degree of spatial agglomeration, and the main distribution pattern is H-H and H-L; 4) The spatial and temporal differentiation of economic efficiency between counties is mainly affected by their resource endowment and county economic division, industrial structure and economic agglomeration level formed on this basis.

  • Huang Yuming
    Download PDF ( ) HTML ( )   Knowledge map   Save

    Coordinating urban-rural coordinated development is an important foundation for achieving economic sustainable development of region. This paper selects 36 prefecture-level units in Northeast China as samples and constructed systematic index system to evaluate the level of urban-rural coordinated development. Then, the paper uses Gini coefficient, spatial autocorrelation and spatial regression to research the spatial pattern and influence mechanism of urban-rural coordinated development in Northeast China in 2005, 2010 and 2015. The result shown that: 1) The regional difference of urban-rural coordination degree in Northeast China has shown an expanding trend, and the phenomenon of spatial agglomeration is obvious, but the intensity of spatial agglomeration is declining. 2) The level of urban-rural coordination varies diferent in different regions. During the study period, Dalian and Jinzhou have always been high level of urban-rural coordinated area, and Chaoyang has always been a low level of urban-rural coordinated area. Hegang and Qitaihe were the most obvious upward cities of urban-rural coordination order, while Harbin and Liaoyuan declined most significantly. 3) From the perspective of spatial pattern, intermediate urban-rural coordination areas increased and moved northward, while primary urban-rural coordination areas decreased and concentrated in the middle. Then, formed a "north-south high, middle low" urban-rural coordination pattern. At the same time, the cold and hot spots of urban-rural coordination are shrinking, and the spatial polarization effect tends to weaken. 4) Urbanization and large-scale agricultural management have a positive effect on urban-rural coordinated development, industrialization does not significantly promote the urban-rural coordination in northeast China and is negatively related to the urban-rural coordination, agricultural modernization plays a positive role in the urban-rural coordinated development. In recent years, transportation gradually plays an positive role in urban-rural coordinated development. Economic development level and informatization level in the urban-rural coordinated development in northeast China are not obvious.

  • Gu Kangkang,Zhu Pengxiang,Ning Yang,Wang Fei
    Download PDF ( ) HTML ( )   Knowledge map   Save

    Air pollution is one of the major environmental problems in cities, which seriously affects urban human health, and traffic exhaust emission is an important cause of air pollution. Green travel is a kind of traffic concept that aims to alleviate urban traffic congestion, urban pollution and other problems by developing low-carbon, green and environment-friendly travel modes based on the requirements of sustainable urban development. The assessment of zoning and regulation of air pollution based on the concept of green travel is significance for improving quality of urban environmental and human settlement environment. Taking the downtown of Hefei China as an example, an urban air pollution assessment framework was constructed based on green travel concept, evaluation indexes of three types were green travel for public transportation, walking and bicycle, the potentiality of green travel modes to improve air pollutant emissions were analyzed by using big data. The results showed that the public transportation had a banding distribution with East-west and North-south direction in the downtown area of Hefei, and the walking and bicycle trips were concentrated in the second ring of the city with high road network density. Green travel showed strong ability to improve air pollutant emissions in the 'one nuclear and two-axis' region; there are two high-vulnerability depressions of Hefei air pollution in first ring and the core area of Binhu; the relationship was explored among green transportation and urban air pollution , it was found that there was a certain spatial trade-off relationship among of them. Finally, the downtown of Hefei is divided into four areas: green travel zone, travel restriction zone, optimized construction zone and potential promotion zonebased on coordination of green transportation, urban air pollution. Optimization strategies were proposed for the air pollution in different regions.

  • Liu Tianbao,Yang Fangfang,Han Zenglin,Peng Fei
    Download PDF ( ) HTML ( )   Knowledge map   Save

    In human-ocean regional system, ocean gets important property of sociality. As for composition, ocean has 4 parts. The first ocean, namely natural ocean, is the naturally existing part of ocean in human-ocean region system. Its core elements are geographical location, physical composition and spatial form. The second ocean, namely artificial ocean, is the built facilities and related material and energy flow in human’s marine practices, including base and facilities, material flow between human subjects and collection & emission between human and ocean. The third ocean, namely relation ocean, is the relationship between human subjects concerning marine practices. Its main contents are subject composition, contents and representation form. The fourth ocean, namely concept ocean, is human’s cognition and perception of ocean and related practices. The core is the idea concerning the relationships between human and ocean, land and ocean and human subjects. In reality, natural ocean, practical ocean and conceived ocean interact one another, producing colorful oceans. With human’s marine practices development, relation and concept oceans, together with natural and artificial oceans, have become marine research and practice focuses.

  • Li Chuanhua,Han Haiyan,Fan Yeping,Cao Hongjuan,Wang Yutao,Sun Hao
    Download PDF ( ) HTML ( )   Knowledge map   Save

    The Tibetan Plateau is the largest plateau in China and the highest altitude in the world. Due to its unique natural conditions, this area not only directly affects the climate change in East Asia, but also has a great impact on the northern hemisphere. However, the Wudaoliang site on this Plateau has not been studied independently. The purpose of this study is to use Biome-BGC model to simulate NPP changes in Wudaoliang from 1961 to 2015. In addition, scenario simulation is also conducted to explore the response of NPP to climate change under different scenarios. Biome-BGC model has strong rationality and systematicness. It is a biogeochemical model in daily for studying the physiological processes and interactions of vegetation and soil energy, water, carbon and nitrogen in regional and global scale ecosystems. The input data of the model are meteorological data, initialized file data, atmospheric CO2 concentration data for many years, vegetation parameter data. The model has been widely applied. In order to improve the accuracy, some parameters, such as leaf C/N ratio and soil particle size, were also measured. In August 2017, the measured samples of grassland vegetation in the flourishing season were validated by directly converting the measured samples into biomass, and compared with previous studies. The verification results showed that the simulated NPP is acceptable and applicable to this area. NPP of Wudaoliang alpine grassland ranged from 57.6 to 79.8 g/(m 2·a), with an average of 67.94 g/(m 2·a), showing an overall growth trend (P<0.01), with an average annual growth rate of 0.18%/a. According to the criterion of Odum ecosystem productivity, the study area is the lowest productivity ecosystem. NPP increased by 5.9%, 11.77%, 17.57% and 23.32% respectively along with the temperature increased by 0.5℃, 1℃, 1.5℃ and 2℃ than the normal scenario. The greater the temperature rise, the more obvious the increase of NPP. In the scenarios of precipitation increasing and decreasing by 20% and 40%, the average NPP changed by 1.13%, 2.14%, 1.19% and -2.45% than normal scenarios. Increasing precipitation could promote the growth of NPP, but decreasing precipitation showed inhibition effect. The combined scenarios of T2W20+, T2W40+, T2W20- and T2W40- increased by 24.54%, 25.68%, 21.79% and 19.94% respectively than normal scenarios. Under the combined scenarios, the NPP increase is higher than that of a single increase in moderate precipitation scenarios. Biome-BGC model with localized parameters can better simulate the net primary productivity of grassland in Wudaoliang area of Tibetan Plateau. In the past 55 years, the net primary productivity of Wudaoliang grassland showed a significant upward trend, which was mainly caused by the extension of growing season and the rapid growth of biomass in September. In this area, temperature increase is beneficial to productivity increase. Precipitation increase is beneficial to productivity acceleration. Precipitation decrease inhibits NPP accumulation. Precipitation change within 40% has no significant effect on productivity. Temperature and precipitation interact with NPP and have an amplifying effect on a single effect.

  • Qi Qinghua,Cai Rongshuo,Guo Haixia
    Download PDF ( ) HTML ( )   Knowledge map   Save

    :Based on percentile and other statistical methods, the climate index was built to analyze the extreme peculiarities of temperature, its space-time evolution and the regional differences in the eastern China (ECM excluding Hongkong Macao and Taiwan), and the associations with the global and regional climatic and oceanic variabilities were discussed. The results show that, in the past 60 years, the long-term warming trend in the ECM is obvious. Due to the influence of latitude and seasons, the response to global warming is most obvious in the northern regions with high latitude and in winter and spring seasons. Compared with the daily minimum temperature, the daily maximum temperature did not distinctly increase especially in the central region between the Yellow River and the Yangtze River. As a result, the diurnal temperature range also showed a decreasing trend overall. In consistent with the average temperature extremes and climatic regioons, the intensity of extreme cold events (ECE) decreased significantly, especially in the north of the Yellow River and southeast coastal areas. However, the long-term trend of the intensity of extreme high temperature events (EHTE) is not obvious, especially in Huanghuai area where the decrease trend dominated. Long-term trends of annual frost and ice days and the cold wave duration experienced a reduce, while the heat wave duration gives priority to increase. The spatial pattern of the intensity and frequency of the extreme events were well consistency, and the response to global changes is remarkable. The impaction index of the ECE possessed greater values in northern region and inland, while lower in the southern regions and coastal areas. The corresponding long-term trend is decline with regional uniformity, especially in the eastern coastal areas. Meanwhile, the impaction index of the ECE in spring is higher than that in winter, and its decline trend is not obvious. The long-term increase trend of impact index of the EHTE was smaller and regional differences are significant. Moreover, the climatic trend in the areas with large values of impaction index was mainly enhanced, while that in the areas with smaller values most significantly weakened. Overall, the frequency of regional extreme temperature events is more sensitive to global climate change than the intensity. The analysis further shows that, the subtropical high, Antarctic and Arctic oscillations may be important factors influencing the formation and evolution of extreme temperature events in the EC.

  • Zhu Xiaohua, Gao Chundong
    Download PDF ( ) HTML ( )   Knowledge map   Save

    This paper conducts an in-depth and systematic analysis on the scientific research evaluation in China which is featured by the over-emphasis on SCI/SSCI publication and over-weighted focus on Impact Factor (IF) and the number of paper publication only. The highly stressed orientation of SCI/SSCI publication in scientific research evaluation has, in a direct or indirect way, brought about the prominent phenomenon of only pursuing the paper publication in academic journals with high IF for scientific researchers. All these have served as the main challenges facing China's academic society, thus urgently needed to be addressed. Therefore, this paper tries to, by conducting perception research in geography field and analyzing nearly 1 000 survey questionnaires disseminated to geography researchers, newly establish a comprehensive model to evaluate the academic value of scientific papers from the five dimensions of indicators, i.e., journal IF, paper citation frequency, paper downloads, social value of papers and innovativeness of papers, as well as identifies the three main pillar aspects for academic value recognition of papers, i.e., related policies on scientific research evaluation and academic status certification, academic achievement influencing power, and academic influencing power evaluation. The results show that the academic achievement influencing power and academic influencing power evaluation are positively correlated to the paper academic value recognition, while the related policies on scientific research evaluation and academic status certification have presented a negative correlation. Besides, the proposed evaluation model in this paper has been empirically applied and tested in selecting and awarding the Most Influential Academic Papers in Chinese geography journals in 2016 and 2018. Finally, by taking geography journals as case study, this paper aims to ease and convert the trend of only focusing on high IF SCI/SSCI publication, promote the evaluation standardization to journals in different languages and disciplines by mutual learning and bringing the gap between different sets of evaluation criteria, yet in a customized way according to the characters, contents and conditions of each discipline, thus providing valuable references to the scientific paper academic value evaluation system reform by other disciplines.