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  • Resources and Strategy
    LI Feng, DING Yuan-yuan, CAI Rong
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    The food supply in China has been adequate and stable for a long time and China has made remarkable achievements in food security which is proved to be true. However, this situation has been challenged by population growth and environmental degradation in recent years. On the one hand, the large population in China is still growing, which makes enormous demands on food supplies. On the other hand, grain production is constrained by resources and the environment, and importing foreign food excessively will squeeze domestic agricultural production. Therefore, the best way to ensure food security in China is to reduce food waste. As an important part of the consumption, households account for a large proportion of food waste production sector, which deserves our attention. What is the current situation of household food waste in China and what factors will affect household food waste in China are worth considering. From the perspective of food conversion, the food waste rate in this paper is defined as the proportion of family food consumption that is not normally converted to body mass index of family members. This paper uses data from China nutrition and health survey (CHNS) and applies stochastic frontier model to estimate household food waste rate from the perspective of food conversion and discusses the impact of heterogeneous family characteristics (such as household size, household structure, household income, storage condition, regional factors, the characteristics of the head of the household and the characteristics of the main female member) on food waste. The result shows that: the average household food waste rate is about 11.28%; such a family is likely to waste more, which has a small size, more children or the elderly, a higher per capita annual income, less-educated head of household, female with higher-education or have jobs, a bad grasp of dietary knowledge, and the family lives in Southern China. Therefore, it is of great importance to encourage the production of small packaging food and small cooking utensils, instruct household members to purchase food according to the actual needs, strengthen the efforts of the government, and raise the awareness of school children and their parents about food security so as to reduce food waste.

  • Resources and Strategy
    LI Yu-rui, BU Chang-li, WANG Peng-yan
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    Agro-product geographical indications (APGIs) are featured agricultural products with names of local region. Creating APGIs is an important means to develop featured agriculture and promote agricultural supply-side reform, and thus boost agricultural industry development and rural vitalization in the new era. It is of great significance to deeply study the regional differentiation characteristics and socio-economic effects of APGIs. This paper took 2274 APGIs as the main data source, combined with socio-economic data and natural geographic data, discussed the spatial pattern of APGIs in China. The research shows that: (1) Overall there are more APGIs in the east and less AGPIs in the west. It presents a pattern of concentration distribution in the horizontal direction, and shows a decreasing trend with the increase of elevation in the vertical direction. (2) There is a big difference in the number of APGIs between provinces. Shandong province has the most APGIs. The per capita APGIs is high in the provinces inhabited by ethnic groups, and the spatial distribution density is high in the provinces with small area and relatively good natural conditions. In the county-level administrative region, there exists a pattern of "large dispersion and small agglomeration", which is significantly related to the primary industry economic index, but the correlation coefficient is not high. (3) All kinds of APGIs, except tobacco and reptiles, show clustering distribution, among which the clustering effect of melon and fruit crops and aquatic products is the most obvious. (4) Different kinds of products have different geographic adaptation zones. Most APGIs require more than 400 mm precipitation, and at least 1600 ℃ for accumulative temperature above 10 ℃, especially between 3200-6400 ℃. (5) Natural geographical conditions, historical and cultural background, socio-economic development and government behaviors are the main factors influencing the regional differentiation of APGIs.

  • Regular Articles
  • Regular Articles
    XIONG Jin-hui, YUE Wen-ze, CHEN Yang, LIAO Rong, FANG Kai
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    In the context of the global initiative for the Sustainable Development Goals (SDGs), cities, as the main place for human activities, are not only the focal point of the SDGs, but also the focus of implementation of the SDGs in countries around the world. Taking the urban areas of the capitals of five Central Asian countries along the Belt and Road as an example, this study sets development scenarios and corresponding parameters towards SDGs, and uses the Markov-FLUS model to simulate the urban development pattern under natural development scenarios, ecological priority scenarios and economic priority scenarios in 2030. The change patterns of urban land use under the SDGs are estimated. The study provide a basis for decision-making in urban development through coordinating the city's society, ecology, and economy from a spatial perspective. The results show that: (1) From 2010 to 2015, the total amount of construction land in the study area increased and the total amount of ecological land decreased. (2) Ecological land fragmentation caused by the expansion of construction land occurred in future scenario simulations, ecological priority scenarios effectively inhibited the expansion of construction land, land converted to bare land has been reduced in the economic priority scenario, and construction land has been continuously expanding. (3) Future urban development should coordinate ecological protection and economic development, integrate ecological protection concepts into urban construction, and implement national policies to promote land resources sustainable use and promotion of the 2030 United Nations Sustainable Development Goals.

  • Regular Articles
    HU Sen-lin, JIAO Shi-tai, ZHANG Xiao-qi
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    Tourism industry has become an important driving force of China's economic growth, and its development has unique characteristics and complexity. Based on the analysis of static (spatial) Markov chain model, the non-static spatial Markov chain model is innovatively introduced to study the spatial-temporal pattern and influencing factors of urban tourism development in China. The results show that: (1) The development of urban tourism in China has the characteristics of long-term and sustainability, and there is a trend of 'path dependence' in general. At the same time, the probability that the low level area of tourism development evolves to the high-level area of tourism development is low, and the phenomenon of 'poverty trap' also exists in urban tourism development. (2) There is close spatial correlation in the evolution of urban tourism development, that is to say, the higher the level of tourism development adjacent to a city, the higher the probability of its transfer to the superior type area; conversely, the lower the level of tourism development adjacent to a city, the higher the probability of its transfer to the sub-type area. (3) The urban tourism development in China is influenced by the level of marketization, the density of star hotels, the endowment of tourism resources and other factors. Finally, in view of the over-commercialization and other problems existing in China's tourism development, we put forward some policy suggestions. Building tourism community is an important way to break the 'path dependence' effect of urban tourism development; then the future tourism development needs to restrain the over-commercialization and highlight the tourism characteristics of each city.

  • Regular Articles
    PAN Qiu-ling, SONG Yu-qiang, CHEN Le, PAN Zhi-kui
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    The development of tourism in China in the last four decades builds China into the ranks of the world's tourism powers. At present, the tourism industry is facing an important task of improving the quality and efficiency in the critical period of transformation and development. Recent research efforts have noted the neglect of regional tourism efficiency studies at county scale. Little research has been done on the county-scale tourism efficiency in Northwest China. To expand our understanding of this topic, this paper focuses on the contributions of the spatial pattern and influencing factors on the tourism efficiency of counties. In this paper, the tourism efficiency and spatial pattern of 107 counties in Shaanxi province was measured based on data envelopment analysis and Python crawling technique. The results showed the following: (1) The number of counties in Shaanxi that have reached the effective overall tourism efficiency was relatively small. The counties with high tourism efficiency were mostly suburban counties. In terms of decomposition, the scale efficiency of county-level tourism in the province was generally higher than that of technical efficiency, which suggests that most counties in Shaanxi were still focusing on large-scale investment in tourism development, but neglect to enhance the capacity of conversing resources. (2) From the analysis of the three geographical units of Shaanxi, the counties with high tourism efficiency in the north area of Shaanxi were mainly concentrated along the Yellow River. Guanzhong area presents the spatial layout of "high in the west and low in the east part", as the counties reaching effective tourism efficiency mainly concentrated along the Longxian-Jingyang-Tongguan county axis. The counties with high tourism efficiency in southern Shaanxi are mostly located at the junction of prefectures and cities. Meanwhile, some counties in the west of Hanzhong bordering neighbor province achieved high tourism efficiency. (3) In the analysis of factors affecting tourism efficiency, the proportion of tourism income to GDP, population density and number of bus stations directly affected tourism overall efficiency and technical efficiency. Tourism resource endowment and population density were the main factors influencing the scale efficiency of county tourism. In addition, the density of highways had a significant influence on it as well. Finally, combined with the research results, this paper provides countermeasures and suggestions for the development of county-level tourism in Shaanxi: optimizing resource allocation and accelerating technological innovation in the region, propelling the differentiated development of tourism and highlighting the tourism characteristics of each county, strengthening exchanges and cooperation between counties and promoting the integration of tourism, culture and other related industries.

  • Regular Articles
    ZHANG Jie, MA Xue-feng
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    Using the nearest neighbor index, geographical contact rate, kernel density analysis, spatial hot spot clustering and other spatial statistical methods, we examined the spatial distribution characteristics and influencing factors of five-star rural tourism areas in Hunan province. The results show that: Firstly, the five-star rural tourism areas are mainly distributed in the eastern part of Hunan. The province can be divided into four sub-regions: Xiangzhong (center), Xiangbei (north), Xiangxi (west) and Xiangnan (south). First-order hotspots are mainly distributed along the city of Changde-Changsha-Zhuzhou-Xiangtan-Hengyang-Chenzhou. The second-order hotspots are only concentrated in the Changsha-Zhuzhou-Xiangtan area. Rural tourism areas have roughly formed three industrial belts with Changsha-Zhuzhou-Xiangtan as the core. Thirdly, the spatial distribution of five-star rural tourism areas is mainly affected by factors such as topographic and hydrologic conditions, economic and social development, transportation location, tourist source market, and regional policy. Relying on the advantages of physical geography, urban economy and policy supply, the five-star rural tourism areas generally present a spatial differentiation pattern of "surrounding the mountain", "near the water", "around the city", and "along the road". According to the conclusions of the analysis and the current situation of rural tourism development in Hunan province, relevant policy suggestions are put forward from the aspects of policy environment, industrial development and rural governance, so as to strengthen the government's guidance to the construction of rural tourism areas, and promote the rational distribution of rural tourism areas. Local policies are further skewed in favour of less developed regions, to adapt to local conditions, integrate the advantages of regional natural and human resources, and promote the development model of rural tourism areas. Further we should strengthen ecological environment governance and improve infrastructure construction in the rural tourism area

  • Regular Articles
    YU Ru-yi, LIANG Liu-ke, SU Xiao-yan, ZHANG Chuan-cai
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    Rural tourism is an important part for implementing the strategy of rural revitalization. Based on the data survey of 375 tourist villages in the city of Luoyang, combined with geographical data and traffic data, this paper uses Bootstrap DEA method, traffic network accessibility algorithm and geographic detector to study the spatial differentiation and formation mechanism of village scale tourism efficiency in Luoyang. Result shows that the correlation between comprehensive efficiency and scale efficiency is significantly higher than that between comprehensive efficiency and pure technical efficiency. This suggests that the comprehensive efficiency of rural tourism development is mainly based on the scale efficiency, and the agglomeration of business units has not improved the pure technical efficiency. The high value areas are distributed around Luoyang and Luanchuan and extended along the Zhengzhou-Lushi Expressway and Luoyang-Luanchuan Expressway. The main factors of spatial differentiation of comprehensive technical efficiency are the tourism carrying capacity of the village and poverty-related factors. In the future, the development of village tourism should follow the path of intensive development, give full play to the combined effects of traffic accessibility, natural part of human settlements environment and agglomeration so as to promote the advanced production factors and innovation of business forms, and guide rural tourism from extensive to intensive development. In rural areas, especially in the mountainous areas of western Henan, the market of tourism elements such as land, labor force, science and technology, finance and information has not really been formed, which restricts the allocation of tourism development elements in the most effective way. Furthermore, the agglomeration effect of tourism elements is not significant and the total factor productivity of tourism is relatively low. Therefore, in order to improve the comprehensive technical efficiency of rural tourism development, it is necessary to strengthen the innovation of land system, tourism statistics and information system, financial market, social organization, and the cultivation of new farmers and management subjects, so as to give full play to the activation effect of the high-level tourism production factors on the rural tourism resources and elements.

  • Regular Articles
    LI He-yao, HE Si-yuan, WANG Guo-ping, DING Lu-bin, JIAO Wen-jun, MIN Qing-wen
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    Protected areas are hot spots for regional disaster risk management while national parks are the important components. Multiple management objectives of national parks determine the diversity of the hazard-bearing bodies that are exposed to a variety of hazards, making the disaster risk management of national parks very comprehensive. From the perspectives of management responsibilities, management planning practice and research hot topic of national parks, this paper summarized the general idea, common features and differences of disaster risk management in global national parks, and proposed three points of inspiration for China from the perspective of socio-ecological system management. First, disaster risk management is necessary for realizing the multiple management goals of national parks. Second, disaster risk management should aim at maintaining the desired state of the socio-ecological system of national parks. Third, disaster risk management should be carried out in an adaptive and holistic way through coordinating hierarchical management goals in an aspect of "vision-goal-objective" of departments concerned.

  • Regular Articles
    TIAN Yun, LIN Zi-juan
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    In this paper, the provincial distribution is completed by constructing a regional distribution model of carbon emission rights. On this basis, the initial space balance is clarified by comparing with the actual carbon emissions in various places. Then, the potential of carbon emission reduction in regions lacking carbon emission rights is comprehensively evaluated. The results show that: (1) The distribution of carbon emission rights in 30 provinces of China is quite different, among which Yunnan has the highest quota, accounting for 10.53%, while Ningxia has the least quota, accounting for only 0.28%. (2) The initial space balance of carbon emission rights in 14 provinces of China shows a surplus state, which can be divided into three types according to the difference of causes, namely "low emission, high quota", "low emission, low quota" and "high emission, high quota". All the other 16 provinces show some degree of deficiency. Combined with the numerical differences, they can be identified into three types: 4 provinces with slight deficiency represented by Jiangsu, 7 with moderate deficiency represented by Tianjin, and 5 with severe deficiency represented by Liaoning. (3) Currently, Zhejiang, Tianjin and Shandong have significantly higher carbon emission reduction potential than other regions, while the carbon emission reduction potential level of each region shows certain convergence but is not completely consistent with a lack of carbon emission rights.

  • Regular Articles
    DENG Xiang-zheng, JIANG Si-jian, LIU Bing, WANG Ze-hao, SHAO Qing
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    In order to quantify the relationship between carbon emissions and temperature rise with the spatially heterogenous distribution of carbon dioxide concentration, this paper used the spatial autocorrelation analysis and the spatial simultaneous equations model to reveal the spatial distribution and aggregation characteristics of global carbon dioxide concentration during 2003-2015 and estimated the impact of carbon emissions on temperature rise based on the grid data of global carbon dioxide concentration, carbon emissions and temperature. The results indicate that carbon dioxide concentration has high value in the northern hemisphere and low value in the southern hemisphere. Spatially heterogenous distribution of carbon dioxide concentration will slightly decrease the estimation results of the impact of carbon emissions on temperature rise. The results show that the spatially heterogenous distribution is an important parameter that should be introduced into the assessment of global warming. At the same time, due to the existence of the spatial scale effect, the selection of spatial range and resolution deserves more attention.

  • Regular Articles
    QIN Zhi-qin, NI Yun-song, JIANG Xiao-li, WANG Rang-hu
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    Mining enterprises are the key elements for achieving regional transformation in resource-based regions. It is of great significance to study the spatial agglomeration characteristics and driving mechanisms of mining enterprises to reveal the spatial process and spatial effects of resource-based regional transformation. The paper takes Shanxi province as an example, and based on the point data of coal mining enterprises, adopts a variety of GIS spatial analysis methods to analyze the evolution of the spatial agglomeration pattern and location change of Shanxi's coal mining enterprises during economic transformation from 1990 to 2017. Furthermore, a negative binomial regression model is constructed to examine the influencing factors of the spatial agglomeration and evolution of coal mining enterprises in the province, and to explain the driving mechanism of the transformation and development of resource-based regions. The results show that: (1) The overall agglomeration changes of coal mining enterprises were relatively stable, but the development connotation has changed significantly, and the enterprises were trending toward large-scale, modern and sustainable development. (2) The spatial agglomeration of coal mining enterprises gradually tended to the direction of coal seam line, and showed the characteristics of low-slope directivity and directivity of adjacent traffic lines. (3) On the macro scale, the spatial concentration of coal mining enterprises presents a trend of dominance of clustering to coexistence of point clustering and band-shaped diffusion along the coal seam line. On the micro scale, the regions with reduced kernel density and regions with increased kernel density had geographical proximity characteristics, which spatially represented the suburbanization process of coal mining enterprises. (4) Resource endowment had the most significant impact on the location selection of coal mining enterprises. Terrain slope, path dependence, provincial roads, corporate ownership, fixed asset investment, and the area of region also had significant effects on location selection of coal mining enterprises. But there are differences in the direction and intensity; the level of urbanization, railways, highways and other elements have no significant impact on the location selection of coal mining enterprises, indicating that the quality of transformation in resource-based regions is constrained by factors such as natural base conditions, industrial development foundations, and regional development stages.

  • Regular Articles
    CHEN Xie-yang, SHI Xing-min
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    The attitude of residents towards resource development is an important social and public basis for resource development management. Based on the survey data of coal mine community residents, this paper empirically analyzes the characteristics of residents' attitude to resource development and the differences of influencing factors. The results show that the residents of coal mine community are generally opposed to the development of resources. The higher the education level of residents is, the greater their support for resource development is; women support coal mining more than men. At the social and cultural levels, employment opportunities and social personal interests have a positive and significant impact on the residents' attitude towards resource development, and the adverse impact of coal mining on the life and health of residents has a negative and significant impact on the residents' attitude towards resource development. In terms of economic and transportation, the construction of supporting facilities for resource development has a positive and significant impact on residents' attitude towards resource development; land destruction and grain production reduction have a negative and significant impact on residents' attitude towards resource development. At the level of ecological environment, the occurrence of natural and geological disasters and the decline of water quality and quantity have a negative and significant impact on the residents' attitude towards resource development. It is suggested that in the future, targeted policies should be formulated to improve residents' attitude towards resource development, and special attention should be focused on the improvement of communication mechanism for resource development, the formulation of residents' participation in resource development planning and the enhancement of external management system construction capacity.

  • Regular Articles
    TANG Fang, LI Yang-bing, WANG Quan, LIU Xiu-ming, WANG Shi-jie
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    The in-depth analysis of the spatial and temporal distribution characteristics and driving mechanism of rural settlements in the karst trough valley area is of great significance for the construction of beautiful new countryside in complex terrain and economically lagging areas. This study, with the support of GIS technology, combined kernel density method, grid method, center-of-gravity model, transect and terrain profile, and used the data from rural settlements in trough valley areas covering years of 2005, 2010, 2014 and 2017, to conduct a comparative analysis of the spatio-temporal evolution characteristics of rural settlements in the study area. The results show that: (1) The rural settlements in trough valleys show a spatial distribution pattern of "small clusters and large scales in the western trough valleys, and large and small scales in the central and eastern trough valleys". (2) The rural residential areas in the western troughs have a tendency to migrate to the trough dam vertically, while the central and eastern troughs are opposite. The terrain of the rural residential areas is: eastern trough valleys > central trough valleys > western trough valleys. (3) The rural residential areas in the western trough valleys present an inverted "U"-shaped distribution pattern with large trough dam heights and low slopes on both sides of the hillside, while the central and eastern trough valleys are opposite. (4) There is a close spatial response relationship between the distribution pattern of rural settlements in the trough valley area and the terrains.

  • Regular Articles
    WANG Shao-jian, WANG Ze-hong
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    In order to promote the coordinated development of the Yangtze River Delta region in the economic transition context, it is of great significance to study the influence of globalization, marketization and decentralization on the expansion of urban land. In this paper, the difference index and the intensity index of urban land expansion are used to analyze the hot spots and each city's sequential variation of urban land expansion in the delta from 2001 to 2015, and the spatio-temporal differentiation of different driving forces' influence is studied by using geographically and temporally weighted regression model. The results show that: (1) In the study area, the urban land expansion has characteristics of spatial concentration in periods, and some areas such as Suzhou-Wuxi-Changzhou are the hot spots of urban land expansion. At the same time, the gap of developmental state of each city will be narrowed with the improvement of regional coordination level. (2) The urban land expansion intensity in the delta showed an upward trend on the whole and on the individual level during the study period, and the average urban land expansion intensity was roughly in line with the circle layer distribution with Shanghai as the center decreasing to the periphery, while the expansion intensity of the peripheral cities increased in a more stable and rapid state. (3) Globalization, marketization and decentralization can well explain the urban land expansion in the region. Globalization is an important driving force for urban development in the delta, and there are obvious regional differences. The development of marketization has significantly promoted the urban development in in Shanghai, South Jiangsu and North Zhejiang, while the developing regions need to further stimulate the dividends of market reform. The fiscal deficit is an important factor for the local governments to implement the strategy of urban expansion, but the development modes will change with the improvement of development level. (4) Among the control variables, the influence of economic development is significant and relatively stable; the population density also plays a significant role in promoting urban land expansion and its influence enhanced in some cities, while the effect of fixed asset investment is more concentrated.

  • Regular Articles
    SUN Qin-ke, ZHOU Liang, TANG Xiang-long, SUN Dong-qi, DANG Xue-wei
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    Oasis city and town is a fragile ecological environment area with the most densely population, the most intense human activities and the most prominent contradiction between human and land in arid regions. Affected by global climate change and China's western development strategy, the dynamic changes between regional towns and oasis cultivated land and the trade-offs between them have become the hotspots of current concern. Based on the multi-temporal remote sensing land use data from 1990 to 2015, this paper takes the oasis cities and towns of the Hexi Corridor, a typical arid area as the research region, introduces Markov and ANN-CA models to deeply explore the land change process, quantifies the temporal and spatial dynamic transformation of urban land and cultivated land, and reveals the process and mechanism of urban expansion from cultivated land. The results show that: (1) The land types in Hexi are mainly unused land and grassland, and the urban and cultivated land accounted for 0.63% and 6.35%, respectively. The urban land and cultivated land areas showed a V-shaped change trend of first decrease and then increase. (2) From 1990 to 2015, the urban area of the expanded by 1.53 times, of which 15.67% was converted from cultivated land, and the others were mainly from unused land such as grasslands, deserts, and Gobi. The proportions of cultivated land occupied by urban expansion in five cities were quite different. (3) The simulation and prediction results combined with the Markov and ANN-CA models show that 79.77% of urban expansion land will come from cultivated land in 2015-2030, and the mode of urban spatial expansion is mainly extended. In addition, the pressure on cultivated land occupied by urban expansion will be greater in the future. The results will provide decision making support for future urban development planning and cultivated land protection.

  • Regular Articles
    SONG Shi-xiong, ZHANG Jin-xi, LIU Zhi-feng, HE Chun-yang
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    Understanding the characteristics of location factors of urban expansion is important to urban sustainable development in the drylands. Taking the Hohhot-Baotou-Ordos-Yulin Urban Agglomeration in China as an example, this study assessed the impacts of location factors on urban expansion using the random forest model. The results indicated that the random forest model can effectively quantify the basic characteristics of location factors of urban expansion in the drylands, with the area under curve (AUC) index of 0.97. The distance to the urban centers had the greatest influence on urban expansion from 1980 to 2017, with the importance of 42.62%. The traffic factors such as highways, national roads, and railways also played an important role with the importance above 10%. All location factors had scaling effects on regional urban expansion, among which the topographic, the climate and the river factors had the most obvious effects. The importance of topography, climate and rivers to large cities was 27.17%, 20.23% and 8.12%, respectively, 4.02 times, 3.91 times and 2.36 times that of small cities. Thus, we suggest that the local governments should pay close attention to the constraint effects of the natural factors (e.g., topography, climate and rivers) on the urban construction in the drylands, and perform urban planning and construction according to local conditions.

  • Regular Articles
    ZHAN Jian-yi, HUANG Guan-chao, ZHOU Hua, DUAN Wen-song, WU An-an, WANG Wen-jie, LI Ting
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    Based on the data of air quality concentration of cities in North China in 2017, the spatial and temporal distribution characteristics of particle concentration in this region are studied. On this basis, the spatial autocorrelation analysis method is used to quantitatively describe the spatial aggregation characteristics of particle concentration in the region, and the spatial measurement model is used to analyze the particle concentration affected cities in North China. The results show that: on the whole, the average frequency of PM2.5 and PM10 pollution is 17.25% and 14.23% respectively in the study area. In terms of temporal distribution, there is a "U"-shaped change in the monthly average concentration of particulate matter in all provinces and cities, the average concentration has obvious seasonal changes, showing a pattern of winter > autumn ≈ spring > summer. In terms of spatial distribution, the annual average concentration of particulate matter in different prefecture-level cities has obvious aggregation characteristics. The high concentration mainly occurs in the south of Hebei province, while the low concentration mainly appears in Inner Mongolia. The spatial econometric model shows that wind speed, rainfall and GDP per capita have a significant negative impact on the average annual concentration of PM2.5 and PM10 of cities in North China, while the proportion of secondary industry, coal use and the number of vehicles have a positive impact on the concentration of particulate matter, among which coal consumption has the largest impact, followed by the number of vehicles. The above results can provide scientific basis for formulating policies for air pollution control in North China.

  • Regular Articles
    ZHANG De-jun, YANG Shi-qi, WANG Yong-qian, SUN Liang, GAO Yang-hua, ZHU Hao, YE Qin-yu
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    The surface information in cloud-covered regions cannot be captured by thermal infrared sensors. Therefore, thermal infrared remote sensing product data have lost their ability to monitor drought in cloudy regions. In this paper, remotely sensed daily land surface temperature reconstruction (RSDAST) model is used to reconstruct LST value of cloud pixels in FY3C/VIRR LST product data, and the reconstructed LST and NDVI data are used to monitor drought in Chongqing in 2018 by TVDI index. And the correlation between soil moisture and OTVDI (original TVDI) and RTVDI (reconstructed TVDI) was examined in this study so that we can evaluate the ability of RTVDI to monitor drought under cloudy conditions. The evaluation results show that the RSDAST model not only expands the spatial scope and temporal continuity of drought monitoring in cloudy regions, but also raises the accuracy of regional drought monitoring (the R value between RTVDI and soil moisture in long time series and spatial distribution is higher than that of OTVDI), which greatly improves the availability and reliability of thermal infrared remote sensing data in cloudy conditions.

  • Regular Articles
    CAO Qi-wen, GU Chao-lin, GUAN Wei-hua
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    China is still experiencing the process of rapid urbanization. How will cultivated land and ecological land, such as woodland, grassland, and water body change? Will construction land continue to grow rapidly? These are not only the concerns of national macro-policy makers, but also the specific problems faced by scholars and ordinary people. This paper attempts to make a multi-scenario analysis of the above issues by constructing a system dynamics (SD) model of China's urbanization based on land use. This SD model integrates the relationship between land use and multi-factors in the urbanization process, including economy and population, and highlights the dominant role of land resources in the urbanization process. The conclusions can be drawn as follows: First, according to the results of stock-flow validation and sensitivity analysis, the China's urbanization SD model based on land use is effective with great reliability and stability. Therefore, the model can be used to predict and simulate the future trend of urbanization process and land resource use in China. Second, in order to meet the requirement of the "National Land Planning Outline (2016-2030)" that the amount of cultivated land should be maintained at 12166.67×104 hm2, there will be a need to supplement 83.17×104-412.67×104 hm2 of cultivated land from other types of land by 2050. This is because the cultivated land will show a decreasing trend in the China's urbanization in the future. In the low scenario, medium and high-speed economic growth, the amount of cultivated land by 2050 will be reduced to 12366.60×104, 12083.50×104, and 11754.00×104 hm2, respectively. Third, with the improvement of urbanization levels, the total amount of construction land will increase accordingly. Specifically, if China's urbanization level reaches 78% by 2050, the total construction land will increase to 4283.89×104-4464.90×104 hm2, with a net increase of 155.87×104-342.88×104 hm2 compared with 2020. Fourth, the overall trend of ecological land in 2020-2050 is to increase first and then decrease. By 2050, the woodland will significantly increase to 29406.60×104-30733.80×104 hm2, the grassland will decrease to 25784.50×104-27809.90×104 hm2, and the water body will not decrease and even increase slightly, the area of which would be 4283.89×104-4464.90×104 hm2. The research results can provide scientific supports for the multi-scenario simulation, evaluation, and decision-making of territorial spatial planning.