25 February 2024, Volume 34 Issue 2 Previous Issue   
Research Articles
Geographical big data and data mining: A new opportunity for “water-energy-food” nexus analysis
YANG Jie, CAO Xiaoshu, YAO Jun, KANG Zhewen, CHANG Jianxia, WANG Yimin
2024, 34 (2):  203-228.  doi: 10.1007/s11442-024-2202-6
Abstract ( )   HTML ( )   PDF (3526KB) ( )  

Since the Bonn 2011 conference, the “water-energy-food” (WEF) nexus has aroused global concern to promote sustainable development. The WEF nexus is a complex, dynamic, and open system containing interrelated and interdependent elements. However, the nexus studies have mainly focused on natural elements based on massive earth observation data. Human elements (e.g., society, economy, politics, culture) are described insufficiently, because traditional earth observation technologies cannot effectively perceive socioeconomic characteristics, especially human feelings, emotions, and experiences. Thus, it is difficult to simulate the complex WEF nexus. With the development of earth observation sensor technologies and human activity perception methods, geographical big data covering both human activities and natural elements offers a new opportunity for in-depth WEF nexus analysis. This study proposes a five-step framework by leveraging geographical big data mining to dig for the hidden value in the data of various natural and human elements. This framework can enable a thorough and comprehensive analysis of the WEF nexus. Some application examples of the framework, major challenges, and possible solutions are discussed. Geographical big data mining is a promising approach to enhance the analysis of the WEF nexus, strengthen the coordinated management of resources and sectors, and facilitate the progress toward sustainable development.

Figures and Tables | References | Related Articles | Metrics
Experience and future research trends of wetland protection and restoration in China
JIANG Weiguo, ZHANG Ze, LING Ziyan, DENG Yawen
2024, 34 (2):  229-251.  doi: 10.1007/s11442-024-2203-5
Abstract ( )   HTML ( )   PDF (1295KB) ( )  

Wetlands are important natural resources for humans and play an irreplaceable ecological function in the terrestrial ecosystem. To curb the continued loss of wetlands globally, international organizations and many countries have taken a series of major conservation and restoration measures. This work reviews these wetland conservation and restoration measures, interprets China’s wetland conservation and restoration management policies, and proposes that future research on wetland resources in China should be conducted from the aspects of international frontiers and national strategic plans, socioeconomics, and smart services. The results show that the 27 International Wetlands Days from 1997 to 2023 provided new goals and tasks for the protection and management of wetlands. The important topics and outcomes of the 14 Conferences of the Contracting Parties to the Convention on Wetlands from 1980 to 2022 provided new directions and new challenges for wetland development. In the future, we should enhance wetland ecological functions, promote sustainable wetland development, and overcome the technical bottleneck of fragile wetland ecosystem restoration. From 1992 to 2022, China embarked on a new phase of wetland protection and restoration. The overall experience of wetland protection and restoration in China has been formed through national strategic deployment, legal policy establishment, and project planning and implementation. The needs to provide for and plan the long-term protection of wetlands at the national level, to innovate restoration and management techniques and application systems, and to effectively address the complex issues of wetland protection and restoration through collaborative division of labor among multiple departments were emphasized. Research on the future trends of wetlands should be directed towards the exploration and practice of the United Nations Sustainable Development Goals and several international conventions in support of sustainable wetland development. Wetland protection, restoration, and management services should be promoted for national strategic needs and local, high-quality social and economic development. In addition, research on cross-integration and academic innovation should be enhanced for disciplinary development, global supervision, comprehensive assessment, and smart decision making.

Figures and Tables | References | Related Articles | Metrics
Spatial and temporal coordinated development research on ecosystem services and human well-being in the typical pastoral area of the Qinghai-Tibet Plateau
REN Siyu, JING Haichao, QIAN Xuexue, LIU Yinghui
2024, 34 (2):  252-288.  doi: 10.1007/s11442-024-2204-4
Abstract ( )   HTML ( )   PDF (4657KB) ( )  

In this study, the interplay between ecosystem services and human well-being in Seni district, which is a pastoral region of Nagqu city on the Qinghai-Tibet Plateau, is investigated. Employing the improved InVEST model, CASA model, coupling coordination model, and hierarchical clustering method, we analyze the spatiotemporal patterns of ecosystem services, the levels of resident well-being levels, and the interrelationships between these factors over the period from 2000 to 2018. Our findings reveal significant changes in six ecosystem services, with water production decreasing by 7.1% and carbon sequestration and soil conservation services increasing by approximately 6.3% and 14.6%, respectively. Both the habitat quality and landscape recreation services remained stable. Spatially, the towns in the eastern and southern areas exhibited higher water production and soil conservation services, while those in the central area exhibited greater carbon sequestration services. The coupling and coordination relationship between ecosystem services and human well-being improved significantly over the study period, evolving from low-level coupling to coordinated coupling. Hierarchical clustering was used to classify the 12 town-level units into five categories. Low subjective well-being townships had lower livestock breeding services, while high subjective well-being townships had higher supply, regulation, and support ecosystem services. Good transportation conditions were associated with higher subjective well-being in townships with low supply services. We recommend addressing the identified transportation disparities and enhancing key regulatory and livestock breeding services to promote regional sustainability and improve the quality of life for Seni district residents, thus catering to the diverse needs of both herdsmen and citizens.

Figures and Tables | References | Related Articles | Metrics
Spatial pattern evolution and driving factors of urban green technology innovation in China
LI Ying, FANG Yuanping, MENG Qinggang
2024, 34 (2):  289-308.  doi: 10.1007/s11442-024-2205-3
Abstract ( )   HTML ( )   PDF (1032KB) ( )  

This study uses green patent data from 264 cities in China between 2006 and 2020 to examine the evolution of spatial patterns in urban green technology innovation (GTI) across the country and identify the underlying driving factors. Moran’s I index, Getis-Ord Gi* index, standard deviation ellipse, and geographical detector were used for the analysis. The findings indicate an increase in the overall level of GTI within Chinese cities. Provincial capitals, cities along the eastern coast, and planned cities emerge as the prominent “highlands” of GTI, whereas the “lowlands” of GTI predominantly lie in the western and northeastern regions, forming the spatial pattern of “hot in the east and center of the country, cold in the northwest and the northeast.” The distribution center of gravity of GTI is toward the southwest of China. The distribution pattern is in the “northeast-southwest” direction, which is characterized by “diffusion,” followed by “agglomeration.” Differences in economic development have the highest determining power on the spatial differentiation of GTI in Chinese cities, whereas differences in environmental regulation and industrial structure have the lowest degree of relative influence. The interaction between any two factors contributes to an amplified explanatory power in understanding the differences in GTI.

Figures and Tables | References | Related Articles | Metrics
Tourism development potential and obstacle factors of cultural heritage: Evidence from traditional music in Xiangxi
ZHANG Xianyong, PENG Baofa, ZHOU Lulu, LU Chunyang, WANG Yali, LIU Rui, XIANG Hui
2024, 34 (2):  309-328.  doi: 10.1007/s11442-024-2206-2
Abstract ( )   HTML ( )   PDF (1747KB) ( )  

Traditional music is an important component of cultural heritage. However, studies have scarcely explored the tourism development potential and the obstacle factors of traditional music. This study takes Xiangxi as the research site, constructs an evaluation index system, and utilizes survey and geographical methods. The major research results are as follows: First, the average potential of resource endowment, tourism industry development, and socio-economic conditions are 0.28, 0.36, and 0.24, respectively. The potential of resource endowment is higher in the west and lower in the east, that of tourism industry development is higher in the north and south and lower in the center, and that of socio-economic conditions is higher in the south and lower in the north. Second, the comprehensive potential is 0.29, which is higher in the northwest and southwest regions. Coordination in most administrative units is at a medium level, and most regions have obvious advantages in resource endowment. Third, the primary obstacle factor is socio-economic conditions (39.21%), followed by resource endowment (30.73%) and tourism industry development (30.06%). The administrative units can be classified into four groups: socio-economic condition obstacle, resource endowment and tourism industry development obstacles, resource endowment and socio-economic condition obstacles, and tourism industry development and socio-economic condition obstacles. The highest priority goals for Xiangxi involve economic development and the integration of modern technologies to stimulate passenger flow. For regions with limited traditional music items (eastern area of Xiangxi), tourism development should be restrained and other resources with stronger inherent advantages should be exploited. This study explored the quantification of traditional music tourism potential, representing a novel breakthrough in this field of research. The indicator system and research methods used in this study can provide guidance and methodological references for cultural heritage research. The suggestions proposed in this article contribute to the rational development and effective protection of cultural heritage resources and the healthy development of the tourism industry.

Figures and Tables | References | Related Articles | Metrics
Land cover change and its response to water level around Tonle Sap Lake in 1988-2020
ZHANG Jing, MA Kai, FAN Hui, HE Daming
2024, 34 (2):  329-354.  doi: 10.1007/s11442-024-2207-1
Abstract ( )   HTML ( )   PDF (5826KB) ( )  

The transboundary influence of environmental change is a critical issue in the Lancang-Mekong region. As the largest river-connected lake in the lower Mekong, the ecological change and influence of Tonle Sap Lake have received widespread attention and discussion, especially after 2008, when the hydrological regime of the Lancang-Mekong River mainstream underwent distinct changes. However, the linkage and coupling mechanism between the lake riparian environment and mainstream water level change are still unclear. In this study, the interannual spatiotemporal changes in land cover in the Tonle Sap Lake riparian zone (TSLRZ) and their relationship with mainstream water levels were analysed. The results showed that the expansion of farmland was the most notable change in 1988-2020. After 2008, the land cover changes intensified, manifested as accelerated farmland expansion, intensified woodland fragmentation and significant water body shrinkage. Furthermore, the responses of the water body, degraded land, wasteland and grassland areas to the mainstream water levels weakened after 2008. Evidently, the land cover changes in the TSLRZ in the last 30 years were less related to the mainstream water level change than to local reclamation and logging. These results can offer a new scientific basis for the transboundary influence analysis of hydrological change.

Figures and Tables | References | Related Articles | Metrics
Quantitative response of vegetation phenology to temperature and precipitation changes in Eastern Siberia
WEN Kege, LI Cheng, HE Jianfeng, ZHUANG Dafang
2024, 34 (2):  355-374.  doi: 10.1007/s11442-024-2208-0
Abstract ( )   HTML ( )   PDF (9223KB) ( )  

Significant changes to the world’s climate over the past few decades have had an impact on the development of plants. Vegetation in high latitude regions, where the ecosystems are fragile, is susceptible to climate change. It is possible to better understand vegetation’s phenological response to climate change by examining these areas. Traditional studies have mainly investigated how a single meteorological factor affects changes in vegetation phenology through linear correlation analysis, which is insufficient for quantitatively revealing the effects of various climate factor interactions on changes in vegetation phenology. We used the asymmetric Gaussian method to fit the normalized difference vegetation index (NDVI) curve and then used the dynamic threshold method to extract the phenological parameters, including the start of the season (SOS), end of the season (EOS), and length of the season (LOS), of the vegetation in this study area in the Tundra-Tagar transitional zone in eastern and western Siberia from 2000 to 2017. The monthly temperature and precipitation data used in this study were obtained from the climate research unit (CRU) meteorological dataset. The degrees to which the changes in temperature and precipitation in the various months and their interactions affected the changes in the three phenological parameters were determined using the GeoDetector, and the results were explicable. The findings demonstrate that the EOS was more susceptible to climate change than the SOS. The vegetation phenology shift was best explained by the climate in March, April, and September, and the combined effect of the temperature and precipitation had a greater impact on the change in the vegetation phenology compared with the effects of the individual climate conditions. The results quantitatively show the degree of interaction between the variations in temperature and precipitation and their effects on the changes in the different phenological parameters in the various months. Understanding how various climatic variations effect phenology changes in plants at different times may be more intuitive. This research provides as a foundation for research on how global climate change affects ecosystems and the global carbon cycle.

Figures and Tables | References | Related Articles | Metrics
Spatiotemporal differentiation and attribution of land surface temperature in China in 2001-2020
TIAN Hao, LIU Lin, ZHANG Zhengyong, CHEN Hongjin, ZHANG Xueying, WANG Tongxia, KANG Ziwei
2024, 34 (2):  375-396.  doi: 10.1007/s11442-024-2209-z
Abstract ( )   HTML ( )   PDF (2675KB) ( )  

The variation of land surface temperature (LST) has a vital impact on the energy balance of the land surface process and the ecosystem stability. Based on MDO11C3, we mainly used regression analysis, GIS spatial analysis, correlation analysis, and center-of -gravity model, to analyze the LST variation and its spatiotemporal differentiation in China from 2001 to 2020. Furthermore, we employed the Geodetector to identify the dominant factors contributing to LST variation in 38 eco-geographic zones of China and investigate the underlying causes of its pattern. The results indicate the following: (1) From 2001 to 2020, the LST climate average in China is 9.6℃, with a general pattern of higher temperatures in the southeast and northwest regions, lower temperatures in the northeast and Qinghai-Tibet Plateau, and higher temperatures in plains compared to lower temperatures in mountainous areas. Generally, LST has a significant negative correlation with elevation, with a correlation coefficient of -0.66. China’s First Ladder has the most pronounced negative correlation, with a correlation coefficient of -0.76 and the lapse rate of LST is 0.57℃/100 m. (2) The change rate of LST in China during the study is 0.21℃/10 a, and the warming area accounts for 78%, demonstrating the overall spatial pattern a “multi-core warming and axial cooling”. (3) LST’s variation exhibits prominent seasonal characteristics in the whole country. The spatial distribution of average value in winter and summer differs significantly from other seasons and shows more noticeable fluctuations. The centroid trajectory of the seasonal warming/cooling area is close to a loop shape and displays corresponding seasonal reverse movement. Cooling areas exhibit more substantial centroid movement, indicating greater regional variation and seasonal variability. (4) China’s LST variation is driven by both natural influences and human activities, of which natural factors contribute more, with sunshine duration and altitude being key factors. The boundary trend between the two dominant type areas is highly consistent with the “Heihe-Tengchong Line”. The eastern region is mostly dominated by human activity in conjunction with terrain factors, while the western region is predominantly influenced by natural factors, which enhance/weaken the change range of LST through mutual coupling with climate, terrain, vegetation, and other factors. This study offers valuable scientific references for addressing climate change, analyzing surface environmental patterns, and protecting the ecological environment.

Figures and Tables | References | Related Articles | Metrics
Lake surface water-heat flux variation and its correlations with meteorological factors on multiscale in the Yamzhog Yumco, south Tibet
ZHANG Xueqin, JIN Zheng, SHEN Pengke, ZHENG Du
2024, 34 (2):  397-414.  doi: 10.1007/s11442-024-2210-6
Abstract ( )   HTML ( )   PDF (3036KB) ( )  

Lake surface water-heat exchange and its climatic attribution critically influence alpine lakes’ evaporation mechanism and water storage balance with climate change. Here, this paper first explored the hourly, daily, and monthly water-heat flux variations of the lake surface and their correlations with meteorological factors based on the eddy covariance turbulent flux observation over the Yamzhog Yumco, an alpine lake in south Tibet in the non-freezing period (April-December) in 2016 and 2017. We found that the average latent heat flux was much higher than the sensible heat flux on the lake surface from April to December. Meanwhile, the water-heat flux exhibited remarkable seasonal variation, with a prominent role of higher air temperature and humidity in summer jointly controlling the lake-air energy exchange. Moreover, the main controlling meteorological factors for the water-heat flux variation of the lake surface differed with diversified timescales. First, the lake-air temperature difference was the most significant meteorological factor related to sensible heat flux on the half-hourly, daily, and monthly timescales. Second, the latent heat flux was strongly positively correlated with wind speed and the synergies of wind speed and water vapor pressure deficit on the daily and half-hourly timescales. Third, the lake surface heat flux was significantly negatively correlated with net radiation flux on the daily and monthly scales. The negative correlation can be attributed to the seasonal variation of the water surface net radiation, and the phase difference in heat flux intensity caused by the lake-air temperature difference and heat capacity contrast. Our findings will hopefully improve the understanding of energy exchange and evaporation mechanisms for alpine lakes in a warming climate.

Figures and Tables | References | Related Articles | Metrics