Content of Regular Articles in our journal

  • Published in last 1 year
  • In last 2 years
  • In last 3 years
  • All

Please wait a minute...
  • Select all
    |
  • Regular Articles
    WANG Shihao, HUANG Lin, XU Xinliang, LI Jiahui
    Journal of Geographical Sciences. 2022, 32(9): 1683-1704. https://doi.org/10.1007/s11442-022-2018-1

    The rapid expansion of China’s urban agglomerations in recent decades has resulted in over-occupied ecological spaces and increased ecological pressure that are restricting healthy regional development. This paper examines the structure and characteristics of distribution of “production-living-ecological” spaces in five mega-urban agglomerations in China: Beijing-Tianjin-Hebei (BTH), the Yangtze River Delta (YRD), Guangdong-Hong Kong-Macao Greater Bay Area (GBA), Chengdu-Chongqing (CY), and the middle reaches of the Yangtze River (MYR). We analyze spatial and temporal variations in the ecological spaces and factors influencing them from 1990 to 2020, and examine the comprehensive ecological carrying capacity and status of ecological spaces in the past 30 years based on the available water resources, regulation of water and air quality, and leisure and recreation. The results show the following: (1) Urban agglomerations in different stages of formation and development represent varying area ratios of “ecological-production-living” spaces. The modes of expansion and evolution of the living spaces are dominated by multi-center combinations as well as the spatial structure of ecological spaces, including barrier, compact, discrete, and fully enveloping spaces. (2) From 1990 to 2020, the area occupied by living spaces in urban agglomerations continued to increase significantly while that of spaces for ecological production decreased. Except in the GBA, ecological spaces have exhibited a trend of increase in area, especially in the past 10 years. The area ratios and spatio-temporal variations in the “production-living-ecological” spaces indicate that the main functions of production and ecological spaces in mega-urban agglomerations have shifted from supply to regulation and culture, and reflect the transition from rapid urbanization to sustainable urbanization in China. (3) The comprehensive ecological carrying capacities of 78.6%, 73.1%, 54.5%, 56.3%, and 25.8% of cities in BTH, YRD, GBA, CY and MYR are severely overburdened. Water supply and the regulation of water quality are the main factors restricting the ecological carrying capacity of BTH and YRD while leisure and recreation services have hindered the capacities of GBA and CY. Policymakers thus need to pay attention to the conservation and rational layout of ecological spaces to reduce the ecological pressure in urban agglomerations. The work here can provide a scientific basis for the green and sustainable development of urban agglomerations as well as the optimized configuration of “production-living-ecological” spaces.

  • Regular Articles
    KUANG Wenhui, ZHANG Shuwen, DU Guoming, YAN Changzhen, WU Shixin, LI Rendong, LU Dengsheng, PAN Tao, NING Jing, GUO Changqing, DONG Jinwei, BAO Yuhai, CHI Wenfeng, DOU Yinyin, HOU Yali, YIN Zherui, CHANG Liping, YANG Jiuchun, XIE Jiali, QIU Juan, ZHANG Hansong, ZHANG Yubo, YANG Shiqi, SA Rigai, LIU Jiyuan
    Journal of Geographical Sciences. 2022, 32(9): 1705-1723. https://doi.org/10.1007/s11442-022-2019-0

    High-resolution mapping and monitoring of national land use/cover changes contribute significantly to the knowledge of the interaction between human activities and environmental changes. China’s Land Use/cover Dataset (CLUD) for 2020 and its dynamic changes in 2015-2020 were developed to extend the CLUD to over 30 years (i.e., the 1980s to 2020 at 5-year intervals) by integrating remote sensing big data and knowledge-based human-computer interaction interpretation methods. This integrating method for CLUD 2020 improved the efficiency of national land use/cover mapping and the accuracy of land use pattern change detection compared to earlier CLUD products, with an overall accuracy of 95%. The intensity of land use change decreased across China in 2015-2020 compared to 2010-2015, although both characteristics of its spatial changes were similar. The cropland area continued to shrink at national scale in 2015-2020, with two regional hotspots including the widespread conversions from dry land into paddy land in Northeast China and the coexistence of widespread land cultivation and cropland abandonment in Xinjiang of Northwest China. Built-up land area continued to expand in China, showing consistency between 2015-2020 and 2010-2015, in which hotspots transited from the surroundings of coastal megacities to the city surroundings of the central and western zones. For natural land, although the woodland and grassland decreased in 2015-2020, its magnitude expanded compared to 2010-2015. In comparison, the water body area in Qinghai-Tibet Plateau increased significantly under the continuous impact of climate change. These characteristics of land use change were closely related to the development strategy of the top-level design of the 13th Five-Year Plan (2016-2020) (e.g., ecological civilization construction and high-quality development).

  • Regular Articles
    BAI Yu, LIU Yansui, LI Yuheng, WANG Yongsheng, YUAN Xuefeng
    Journal of Geographical Sciences. 2022, 32(9): 1724-1744. https://doi.org/10.1007/s11442-022-2020-7

    Eco-environmental sustainability is the basis for sustainable development in ecologically fragile areas. Land consolidation plays an important role in coordinating human-land relationships and achieving economic growth and eco-environment protection. Taking the Loess Plateau as the study area, this paper diagnoses the associated eco-environmental problems and their chain effect. The research results show that the overall eco-environment of the region is still relatively fragile. An eco-environment multi-subject co-management model, a scale-differentiated management model, and an elements comprehensive management model are proposed to improve the eco-environmental management efficiency after implementing land consolidation in the plateau. This paper takes the Gully Land Consolidation Project in Baota district of Yan’an city in Shaanxi province as an example to illustrate the relationship between land consolidation and eco-environmental sustainability in the Loess Plateau. Policy implications for eco-environmental protection in the Loess Plateau are proposed.

  • Regular Articles
    LIU Mengxue, GAO Ya, WEI Hejie, DONG Xiaobin, ZHAO Bingyu, WANG Xue-Chao, ZHANG Peng, LIU Ranran, ZOU Xinyu
    Journal of Geographical Sciences. 2022, 32(9): 1745-1765. https://doi.org/10.1007/s11442-022-2021-6

    The nexus exploration among land use/land cover change, ecosystem services and human well-being has been increasingly crucial in the context of Future Earth. However, the spatial heterogeneity and the entwining process among these three aspects have not yet been in-depth and systematically explored. Here we identified the spatiotemporal pattern of ecosystem services during the past 20 years in Yushu, the eco-fragile region and the centre of Qinghai-Tibet Plateau, as well as clarified its relationships with land use change and human well-being. We revealed that: (1) The structure of the ecosystem and land use in this area have been increasingly stable, and the ecological projects have exerted a positive impact. (2) Although the ecological environmental issues still need more attention, the ecosystem services of the area have been positively developing. (3) Derived by the ecosystem services increase, environmental projects and policies, the human well-beings of culture and education performed much better than other aspects. (4) It is crucial to carry out long-term ecological projects and increase educational investment for maintaining the stability of this ecologically fragile area. This study provides significant support for the regional ecological sustainability decision making, especially for the Qinghai-Tibet Plateau, the roof of the world.

  • Regular Articles
    MU Xufang, FANG Chuanglin, YANG Zhiqi
    Journal of Geographical Sciences. 2022, 32(9): 1766-1790. https://doi.org/10.1007/s11442-022-2022-5

    The continuous growth of urban agglomerations in China has increased their complexity as well as vulnerability. In this context, urban resilience is critical for the healthy and sustainable development of urban agglomerations. Focusing on the Beijing-Tianjin-Hebei (BTH) urban agglomeration, this study constructs an urban resilience evaluation system based on four subsystems: economy, society, infrastructure, and ecology. It uses the entropy method to measure the urban resilience of the BTH urban agglomeration from 2000 to 2018. Theil index, standard deviation ellipse, and gray prediction model GM (1,1) methods are used to examine the spatio-temporal evolution and dynamic simulation of urban resilience in this urban agglomeration. Our results show that the comprehensive evaluation index for urban resilience in the BTH urban agglomeration followed a steady upward trend from 2000 to 2018, with an average annual growth rate of 6.72%. There are significant differences in each subsystem’s contribution to urban resilience; overall, economic resilience is the main factor affecting urban resilience, with an average annual growth rate of 8.06%. Spatial differences in urban resilience in the BTH urban agglomeration have decreased from 2000 to 2018, showing the typical characteristic of being greater in the central core area and lower in the surrounding non-core areas. The level of urban resilience in the BTH urban agglomeration is forecast to continue increasing over the next ten years. However, there are still considerable differences between the cities. Policy factors will play a positive role in promoting the resilience level. Based on the evaluation results, corresponding policy recommendations are put forward to provide scientific data support and a theoretical basis for the resilience construction of the BTH urban agglomeration.

  • Regular Articles
    Shobhit CHATURVEDI, Kunjan SHUKLA, Elangovan RAJASEKAR, Naimish BHATT
    Journal of Geographical Sciences. 2022, 32(9): 1791-1812. https://doi.org/10.1007/s11442-022-2023-4

    Analyzing long term urban growth trends can provide valuable insights into a city’s future growth. This study employs LANDSAT satellite images from 1990, 2000, 2010 and 2019 to perform a spatiotemporal assessment and predict Ahmedabad’s urban growth. Land Use Land Change (LULC) maps developed using the Maximum Likelihood classifier produce four principal classes: Built-up, Vegetation, Water body, and “Others”. In between 1990-2019, the total built-up area expanded by 130%, 132 km2 in 1990 to 305 km2 in 2019. Rapid population growth is the chief contributor towards urban growth as the city added 3.9 km2 of additional built-up area to accommodate every 100,000 new residents. Further, a Multi-Layer Perceptron - Markov Chain model (MLP-MC) predicts Ahmedabad’s urban expansion by 2030. Compared to 2019, the MLP-MC model predicts a 25% and 19% increase in Ahmedabad’s total urban area and population by 2030. Unaltered, these trends shall generate many socio-economic and environmental problems. Thus, future urban development policies must balance further development and environmental damage.

  • Regular Articles
    LIAO Weihua, JIANG Weiguo, HUANG Ziqian
    Journal of Geographical Sciences. 2022, 32(9): 1813-1830. https://doi.org/10.1007/s11442-022-2024-3

    Accurate and rapid evaluation of the regional eco-environment is critical to policy formulation. The remote sensing ecological index (RSEI) model of the Guangxi Beibu Gulf Economic Zone (GBGEZ) during 2001-2020 was established and evaluated using four indices: dryness, wetness, greenness, and heat. This paper proposes an information granulation method for remote sensing based on the RSEI index value that uses granular computing. We found that: (1) From 2001 to 2020, the eco-environmental quality (EEQ) of GBGEZ tended to improve, and the spatial difference tended to expand. The regional spatial distribution of the eco-environment is primarily in the second-level and third-level areas, and the EEQ in the east and west is better than that in the middle. The contribution of greenness, wetness, and dryness to the improvement of EEQ in the study region increased year by year. (2) From 2001 to 2020, the order of the contribution of the EEQ index in the GBGEZ was dryness, wetness, greenness, and heat. (3) The social and economic activities in the study region had a certain inhibitory effect on the improvement of the EEQ.

  • Regular Articles
    LI Xia, LIU Zhenhai, WANG Shaoqiang, LI Fengting, LI Hui, ZHU Tongtong, QIAN Zhaohui, TU Yongkai, LIU Yuanyuan, WANG Xiaobo, WANG Qinyi, SHI Weibo, LI Donghui
    Journal of Geographical Sciences. 2022, 32(9): 1831-1846. https://doi.org/10.1007/s11442-022-2025-2

    In tropical regions, mangrove forests are located in the inter-tidal areas between land and sea, and are at risk from both freshwater and seawater floods. Using satellite-derived Normalized Difference Vegetation Index (NDVI) products, this study compared the differences in resistance and resilience of mangrove ecosystems to freshwater and seawater floods in Southeast Asia, and analyzed the spatial characteristics of the stability of mangrove ecosystems under floods in representative areas. Results show that mangroves tended to have lower mean resistance (28.24 vs. 37.32) and higher mean resilience (3.74 vs. 3.56) under freshwater floods, compared to seawater floods. Their resistance increased with the distance from rivers, such that the resistance of coastal areas to freshwater and seawater floods was lower than that of inland areas. These areas with lower resistance showed higher resilience compared to those with higher resistance. Damaged mangroves hardly fully recovered to their normal NDVI levels one year after seawater floods, especially in coastal areas. Although the occurrence of seawater floods was relatively rare in the past, it is likely to increase under more-intense climate extremes in the future, and the threat to the survival of mangroves may also increase. Thus, it is essential to evaluate the stability of mangrove ecosystems under floods.

  • Regular Articles
    WU Shihai, YAN Jianzhong, ZHANG Yili, PENG Ting, SU Kangchuan
    Journal of Geographical Sciences. 2022, 32(9): 1847-1865. https://doi.org/10.1007/s11442-022-2026-1

    Traditional trade routes that penetrate the natural barrier of the Himalayas are critical for connecting major Chinese and South Asian markets. Research on these trade routes can contribute significantly to facilitating the construction of the South Asian Corridor and enhancing trans-Himalayan connectivity. Combining historical literature, field surveys, and geographic information system (GIS) techniques, this study examined the spatial distribution characteristics and evolution process of the routes, focusing on transverse valleys of the Himalayan arc. The key findings were as follows. First, there are 21 traditional trade routes traversing the Himalayan region: six Sino-Nepalese routes, four Sino-Bhutanese routes, and eleven Sino-Indian routes. Second, the evolution of traditional trade routes has entailed five distinct phases: an incipient period (pre-7th century), formation (7th century-842 AD), development (842-1959), decline (1959-1962) and recovery (1962-present). Third, the incipient and formative developmental phases were prompted by the spread of Buddhism and the exchange of goods. The stability of local governments in Tibet and Central China and favourable border trade policies along with Britain’s colonial expansion and commercial interests stimulated further development of traditional trade routes. However, India’s strategic miscalculation and “Forward Policy” instigated the decline phase, while the demands of regional cooperation and development are currently the key drivers of the restoration and construction phase. Finally, to shelve disputes, promote cooperation and development, and enhance political mutual trust, governments should recover and construct traditional trade routes by replanning and constructing border trade markets, expanding border trade, developing pilgrimage and tourism, and strengthening cross-border cooperative research under global climate change.

  • Regular Articles
    LI Yuheng, WU Wenhao, WANG Yongsheng
    Journal of Geographical Sciences. 2021, 31(8): 1159-1170. https://doi.org/10.1007/s11442-021-1890-4

    There is less than a decade left to accomplish the goal of ending global poverty by 2030. This paper investigates global poverty dynamics and finds a shift in the world's poverty gravity center from South Asia to Africa in the period 1990-2015. Sub-Saharan Africa has become the main battlefield for poverty reduction in the world. Global poverty reduction has been accompanied by political instability and local conflicts, economic marginalization, rural decline, and natural hazards as well as climate change which are jointly impacting the least developed areas and making the world's poverty reduction vulnerable to external shocks. The “STAR” scheme, including maintaining political stability, promoting targeted poverty alleviation, implementing regular assessments of poverty reduction initiatives, and revitalizing rural and poverty-stricken areas, is proposed with specific measures to enhance the resilience capacity of poverty alleviation in the world.

  • Regular Articles
    NIU Fangqu, JIANG Yanpeng
    Journal of Geographical Sciences. 2021, 31(8): 1171-1186. https://doi.org/10.1007/s11442-021-1891-3

    Since the implementation of the economic reform and opening up policy in 1978, China has miraculously created long-term high-speed economic growth, but has also had to face the problem of excessive consumption of resources as well as an intensification of environmental pollution. As a result, China is now facing a slowdown in development. China must maintain a certain speed of development to realize its goal of being a powerful nation, and becoming a developed country by 2050. To this end, China is facing a transformation of its economic development. There is a need to agree on an expected economic growth rate, along with the corresponding development modes or means of regulation in the medium- and long-term periods. This study developed a systematic-dynamic model to simulate the coupling relationship between economic growth, development modes, and the environmental supply system, and explored the possible options for future economic growth as well as the resource use and environmental protection requirements (the main factors). The results showed that to achieve the development goal of becoming a developed country by 2050, while maintaining a good ecological environment, the suitable growth rate for China's economy is 3.8%-6.3%. Within this range, a growth rate of 3.8%-4.4% was found to be relatively safe, while a growth rate of 4.4%-6.3% required further technical progress. This study provides an early warning in regard to China's environmental and development status. The study was a response to the “Future Earth” framework document and, in terms of development speed, it developed a theoretical system for the determination of resource and environmental carrying capacity (RECC).

  • Regular Articles
    Ilan STAVI, Eli ZAADY, Alexander GUSAROV, Hezi YIZHAQ
    Journal of Geographical Sciences. 2021, 31(8): 1187-1204. https://doi.org/10.1007/s11442-021-1892-2

    A long-term drought has led to the mass mortality of shrubs in the semi-arid Israeli Negev. The most impacted shrub species is the Noaea mucronata (Forssk.) Asch. and Schweinf. In a four-year study, we found that herbaceous vegetation growth was greater in the dead shrub patches than in the surrounding inter-patch biocrusted spaces, suggesting that the dead shrub patches encompass improved micro-habitats. However, unexpectedly, the soil moisture in the dead shrub patches was consistently lower than that of the inter-patch biocrusted spaces. At the same time, soil quality in the dead shrub patches was higher than that in the inter-patch spaces. Therefore, it seems that the overall better soil conditions in the dead patches overcome the scarcity of soil-water, supporting increased herbaceous productivity. For explaining the discrepancy between herbaceous vegetation and soil-water, we formulated a conceptual framework, which highlights the key factors that regulate soil-water dynamics in this dryland ecosystem. We demonstrate that herbaceous vegetation is facilitated in the dead shrub patches by a legacy effect that takes place long after the shrubs have died. The dead shrub patches encompass a unique form of ecosystem engineering. The study high- lights the complex and unpredicted impacts of prolonged droughts on dryland ecosystems.

  • Regular Articles
    ZHANG Xueru, ZHOU Jie, LI Guoning, CHEN Chun, LI Mengmei, LUO Jianmei
    Journal of Geographical Sciences. 2020, 30(4): 601-620. https://doi.org/10.1007/s11442-020-1745-4

    Reconstruction of the spatial pattern of regional habitat quality can revivify the ecological environment background at certain historical periods and provide scientific support for revealing the evolution of regional ecological environmental quality. In this study, we selected 10 driving factors of land use changes, including elevation, slope, aspect, GDP, population, temperature, precipitation, river distance, urban distance, and coastline distance, to construct the CA-Markov model parameters and acquired the land use spatial data for 1975, 1980, 1985, 1990, and 1995 by simulation based on the land use status map for 2010. On this basis, we used the InVEST model to reconstruct the spatial pattern of habitat quality in the study area and conducted classification division and statistical analysis on the computed habitat degradation degree index and the habitat quality index. (1) The results showed that from 1975 to 2010, the habitat degradation degree gradually increased, and the habitat degradation grade spatially presented a layered progressive distribution. Habitat quality presented a constantly decreasing trend. The high-value zones were mainly distributed in the mountainous areas, while the low-value zones were mostly located in built-up areas. During the period of 1975-2010, low-value zones gradually expanded to their surrounding high-value zones, and the high-value zones of habitat quality tended to be fragmented. (2) The spatial-temporal variation characteristics of habitat quality from 1975 to 2010 showed that the regions with low habitat quality were difficult to be restored and mostly maintained their original state; the regions with poor habitat quality, which accounted for 6.40% of the total study area, continued to deteriorate, mainly around built-up areas; the regions with good and superior habitat quality, which accounted for 5.68% of the total study area, were easily converted to regions with bad or poor habitat quality, thus leading to the fragmentation of the regional habitat. (3) From 1975 to 2010, land use changes in the study area were significant and had a huge influence on habitat quality; the habitat quality in the study area decreased consistently, and the area of the regions with bad and poor habitat quality accounted for more than 60% of the total study area. Construction land was the largest factor threatening habitat quality.

  • Regular Articles
    YANG Wenjie, GONG Qianwen, ZHANG Xueyan
    Journal of Geographical Sciences. 2020, 30(4): 621-641. https://doi.org/10.1007/s11442-020-1746-3

    The calculation of ecological compensation and boundary identification of stakeholders represent the key challenges for Beijing-Tianjin-Hebei Region in its implementation of the trans-regional ecological compensation mechanism. Breaking administrative boundaries and spatially coordinating ecological resources helps to restructure an ecological compensation mechanism of the region based on the coordinated development of Beijing, Tianjin and Hebei. According to the estimated ecological assets in the counties of the region in 2000, 2005, 2010 and 2015, a quantitative model for total ecological compensation was built based on ecological assets and county-level economic development. Then, the spatiotemporal distribution characteristics of the total ecological compensation in the region were defined, and the boundaries of ecological surplus and deficit areas were identified. Results indicate: (1) The region’s annual average ecological assets amounted to ¥1379.47 billion; in terms of annual total ecological assets, Hebei ranked first (¥1123.80 billion), followed by Beijing (¥157.46 billion) and Tianjin (¥98.21 billion); and in terms of ecological assets per unit area, Beijing ranked first, Tianjin second and Hebei last. (2) Among ecosystem services, hydrological regulation and climate regulation had the highest annual average value and contributed most to the increase in ecological assets. In 2015, the contribution of water and soil conservation to the total ecological assets decreased to -15.66%, showing the degradation of the function played by different ecosystems. (3) The ecological surplus of the region in four periods of 2000, 2005, 2010 and 2015 were ¥398.98 billion, ¥870.37 billion, ¥1254.93 billion and ¥2693.94 billion respectively, basically offsetting the ecological deficit of each corresponding period, but the urgency for ecological compensation was increased. (4) The ecological surplus and deficit areas showed a great fluctuation in different time periods. Larger time span means more noticeable convergence of deficit areas towards central and eastern areas. Public resources such as education, transportation and medical care in central urban areas should be decentralized to encourage population dispersal, weaken the agglomeration effect of deficit areas and finally achieve the ecological synergy of the region.

  • Regular Articles
    ZHAO Fang, LIU Junjie, ZHU Wenbo, ZHANG Baiping, ZHU Lianqi
    Journal of Geographical Sciences. 2020, 30(4): 642-656. https://doi.org/10.1007/s11442-020-1747-2

    To determine the dividing index between warm temperate and subtropical zones based on the spectra of altitudinal belts, this paper collected 33 spectra of altitudinal belts in the Qinling-Daba Mountains from published literatures and then analyzed the structures and the spatial patterns from south to north, from west to east and based on exposure directions. The results show that: 1) From south to north, the basal belt gradually changes from subtropical evergreen broadleaf forest to warm temperate deciduous broadleaf forest; the spectra of altitudinal belts change from complex to simple; the dominant belt changes from montane broadleaf-conifer mixed forest and evergreen-deciduous broadleaf mixed forest to deciduous broadleaf forest. 2) From west to east, the structures of the altitudinal belt spectra show complexity in the east and west but simplicity in the middle section; the upper limits of both the evergreen-deciduous broadleaf mixed forest belt and montane deciduous broadleaf forest belt present a quadratic curve distribution pattern in the longitudinal direction. However, the upper limit of the montane broadleaf-conifer mixed forest belt exhibits a nearly linear decrease in the west-east direction. 3) Both the north and south slopes in the Qinling Mountains have the similar basal belt, whereas it varies greatly between the north and south slopes in the Daba Mountains. Comparably, dominant belts are very similar in the Qinling Mountains and the north slope of the Daba Mountains, but the south slope of the Daba Mountains has its own unique dominant belt: evergreen-deciduous broadleaf mixed forest. This implies that the Daba Mountains are more appropriate than the Qinling Mountains to act as the boundary between subtropical and warm-temperate zones in central China.

  • Regular Articles
    ZHAO Ting, BAI Hongying, YUAN Yuan, DENG Chenhui, QI Guizeng, ZHAI Danping
    Journal of Geographical Sciences. 2020, 30(4): 657-668. https://doi.org/10.1007/s11442-020-1748-1

    Based on air temperature observation data from 32 meteorological stations, temperature changes in the middle Qinling Mountains from 1959 to 2016 were analysed with respect to the north-south, seasonal and altitude differences. Our research mainly showed the following results. The annual temperature (TA) rose approximately 0.26℃/10a within the past 58 years. This warming trend was stronger on the northern slope than on the southern slope, and a warming trend reversal occurred in 1994 on the northern slope, which was three years earlier than on the southern slope. The temperature changes for the four seasons were not synchronized, and the trend in spring contributed the most to the TA trend, followed by winter, autumn, and summer. The temperature difference between summer and winter (TDSW) decreased significantly over the past 58 years. The temperature change in the middle Qinling Mountains was clearly dependent on altitude. With increases in altitude, the TA increased gradually and became stronger while the TDSW decreased gradually and became weaker. Differences in temperature change between the north and south were mainly observed in low-altitude areas. With increase in altitude, the differences gradually tended to disappear.

  • Regular Articles
    SONG Xiaoqing, WEN Mengmeng, SHEN Yajing, FENG Qi, XIANG Jingwei, ZHANG Weina, ZHAO Guosong, WU Zhifeng
    Journal of Geographical Sciences. 2020, 30(4): 669-687. https://doi.org/10.1007/s11442-020-1749-0

    Urban growth and shrinkage constitute the overall pattern of growing urbanization across the globe. Studies on urban vacant land (UVL) are few, and have proved to be mainly rudimentary and subjective. This paper first presents the definition of UVL based on bibliometric analysis. Typology, morphology, proximate causes, and the multiple functions of UVL are then analyzed at parcel, transect, city, and national levels based on an international review. Results show that UVL can be categorized by land cover, land usage, and land ownership. Worldwide, UVL has been widespread and extensive. For example, the occurrence probabilities of UVL in the cases of Guangzhou and New York are 8.46%-8.88% and 3.17%-5.08%, respectively. The average vacancy rate of residential land amounts to 11.48% in 65 U.S. cities. Generally, UVL shows fragmentation and irregular shape, and significant spatial differences exist at parcel, transect, city, and national levels. Proximate causes, such as excessive land division, irregularly shaped land parcels, decreases in resident population, deindustrialization, land speculation, insufficient investment, and environmental concerns, can all result in UVL. Currently, UVL has become a gray area of social, economic, and ecological space. However, it can also be considered a potential resource for enhancing urban sustainability. Policy implications to promote urban sustainability using monitoring, control, and differential revitalization of UVL are presented.

  • Regular Articles
    Qifei ZHANG, Yaning CHEN, Zhi LI, Yupeng LI, Yanyun XIANG, Wei BIAN
    Journal of Geographical Sciences. 2019, 29(6): 984-1000. https://doi.org/10.1007/s11442-019-1640-z

    In this study, we analyzed glacier changes in the Aksu River Basin during the period 1975-2016, based on Landsat MSS/TM/ETM+/OLI imagery analysis and the Chinese Glacier Inventory (CGI). The results showed that the total number, area, and volume of the studied glaciers in the Aksu River Basin decreased by 202 (7.65%), 965.7 km2 (25.88%), and 74.85-78.52 km3 (23.72%-24.3%), respectively. The rate of glacier retreat in the basin was slower in the north, northwest and west, but reached the highest in the east (measuring 0.86% yr-1). Furthermore, there were significant regional differences in the distribution and change of glaciers, the Kumalak River Basin had the largest glacier number and area, about 63.15% and 76.47% of the studied basin, and the rate of glacier retreat in the Kumalak River Basin was 0.65% yr-1, it was higher than the Toxkan River Basin which reached 0.57% yr-1. We found the shrinkage rate of glacier for different periods in the past 41 years, during 1975-1990 the glaciers showed the greatest retreat, while the rate of glacier area retreat slowed down significantly from 1990 to 2000. In recent 16 years since 2000, the rate of glacier retreat in the Toxkan River Basin was higher compared with 1990-2000. The RGI50-13.04920 glacier of Kumalak River Basin had been in a state of retreat since 1990. Over the past 41 years, the temperature and precipitation in the Aksu River Basin increased obviously, and the warming temperatures were clearly the main reason for glacier retreat in the region, while the increased precipitation in the mountain area may have a direct relation with the retreating rate of glaciers.

  • Regular Articles
    Wenlan GAO, Keqin DUAN, Shuangshuang LI
    Journal of Geographical Sciences. 2019, 29(6): 971-983. https://doi.org/10.1007/s11442-019-1668-0

    Among the most devastating extreme weather events, cold surge (CS) events frequently impact northern China. It has been reported that extreme weather events will increase in the global warming context. However, the direct evidence of this hypothesis is limited. Here, we investigated the changes in frequency, number, duration, and temperature of CS events in northern China using the daily minimum temperature dataset of 331 stations from 1960 to 2016. The results indicate that the annual CS events in terms of frequency and number decreased, and the duration shortened as the starting date was later and the ending date earlier. Meanwhile, the annual CS temperature increased. In addition, spatial trends in the CS events in terms of frequency, number, and duration decreased while the CS temperature increased in most regions of northern China. We interpreted these variations as a response to global warming. However, the extreme CS events in terms of frequency, number and the earliest starting date and the latest ending date showed little change though the extreme CS temperature increased, implying climate warming had not limited extreme CS events. The adverse effect of CS events on agriculture and human health remain concerning.

  • Regular Articles
    Li ZENG, Jing LI
    Journal of Geographical Sciences. 2019, 29(6): 1021-1038. https://doi.org/10.1007/s11442-019-1642-x

    Water conservation is one of the most important ecosystem services of terrestrial ecosystems. Identifying the optimization regions of water conservation using Bayesian belief networks not only helps develop a better understanding of water conservation processes but also increases the rationality of scenario design and pattern optimization. This study establishes a water conservation network model. The model, based on Bayesian belief networks, forecasts the distribution probability of the water conservation projected under different land use scenarios for the year 2050 with the CA-Markov model. A key variable subset method is proposed to optimize the spatial pattern of the water conservation. Three key findings were obtained. First, among the three scenarios, the probability of high water conservation value was the largest under the protection scenario, and the design of this scenario was conducive to the formulation of future land use policies. Second, the key influencing factors impacting the water conservation included precipitation, evapotranspiration and land use, and the state set corresponding to the highest state of water conservation was mainly distributed in areas with high annual average rainfall and evapotranspiration and high vegetation coverage. Third, the regions suitable for optimizing water conservation were mainly distributed in the southern part of Maiji District in Tianshui, southwest of Longxian and south of Weibin District in Baoji, northeast of Xunyi County and northwest of Yongshou County in Xianyang, and west of Yaozhou District in Tongchuan.

  • Regular Articles
    Liying SUN, Haiyan FANG, Qiangguo CAI, Xihua YANG, Jijun HE, John L. ZHOU, Xunming WANG
    Journal of Geographical Sciences. 2019, 29(6): 1001-1020. https://doi.org/10.1007/s11442-019-1641-y

    It is of great significance to quantify sediment load changing with erosion processes for improving the precision of soil loss prediction. Indoor rainfall experiments were conducted in 2 rainfall intensities (90 mm·h-1 and 120 mm·h-1), four slope gradients (17.60%, 26.80%, 36.40%, 46.60%) and 2 slope lengths (5 m, 10 m). Erosion processes are divided into five stages. Results show that sediment yield is mainly sourced from rill erosion, contributing from 54.60% to 95.70% and the duration of which is extended by slope gradients. Sediment load and sediment concentration are significantly different along erosion stages, with the highest values in rill development stage (SIV). Surface flow velocities (interrill and rill) demonstrate less significant differences along erosion stages. Rainfall intensity increases sediment load in all stages, with up to 12.0 times higher when changing from 90 to 120 mm·h-1. There is an increasing trend for sediment load and sediment concentration with the rising slope gradient, however, fluctuations existed with the lowest values on 26.80% and 36.40%, respectively, among different treatments. The slope gradient effects are enhanced by rainfall intensity and slope length. Results from this study are important for validating and improving hillslope erosion modelling at each erosion stage.