Mobile internet and wireless communication technologies have produced unprecedented location-aware data. Such big geospatial data can be used as a proxy measure of the ‘digital footprints’ left by us on the planet and provide a valuable opportunity to understand the dynamic and short-term human disturbance on the nature at fine scales. This study investigated the spatiotemporal variations of human’s digital footprints on the Qinghai-Tibet Plateau using smartphone-users-generated Tencent’s location request data. The results showed that human’s digital footprints cover less than 5% of Qinghai and Tibet, exhibiting either a U-shaped or an N-shaped temporal change pattern during the major festivals. Spatial changes of the digital footprints manifested a transition process from dispersion to concentration in Xining and Lhasa. Human disturbance assessment of seven large nature reserves on the plateau showed that the Qinghai Lake is the most disturbed one as shown by 14.6% of its area is stained with human digital footprints and the areal average of footprint intensity is 1.59, and the disturbance was significantly escalated during the National Day holiday. By contrast, the Qangtang and Hoh Xil are the least affected nature reserves with the two indices less than 1% and 0.1, respectively.
Developing a comprehensive understanding of inter-city interactions is crucial for regional planning. We therefore examined spatiotemporal patterns of population migration across the Qinghai-Tibet Plateau (QTP) using migration big data from Tencent for the period between 2015 and 2019. We initially used decomposition and breakpoint detection methods to examine time-series migration data and to identify the two seasons with the strongest and weakest population migration levels, between June 18th and August 18th and between October 8th and February 15th, respectively. Population migration within the former period was 2.03 times that seen in the latter. We then used a variety of network analysis methods to examine population flow directions as well as the importance of each individual city in migration. The two capital cities on the QTP, Lhasa and Xining, form centers for population migration and are also transfer hubs through which migrants from other cities off the plateau enter and leave this region. Data show that these two cities contribute more than 35% of total population migration. The majority of migrants tend to move within the province, particularly during the weakest migration season. We also utilized interactive relationship force and radiation models to examine the interaction strength and the radiating energy of each individual city. Results show that Lhasa and Xining exhibit the strongest interactions with other cities and have the largest radiating energies. Indeed, the radiating energy of the QTP cities correlates with their gross domestic product (GDP) (Pearson correlation coefficient: 0.754 in the weakest migration season, WMS versus 0.737 in the strongest migration season, SMS), while changes in radiating energy correlate with the tourism-related revenue (Pearson correlation coefficient: 0.685). These outcomes suggest that level of economic development and level of tourism are the two most important factors driving the QTP population migration. The results of this analysis provide critical clarification guidance regarding huge QTP development differences.
As one of the most ecologically sensitive issues in the world, migration now plays an important role in population growth on the Qinghai-Tibet Plateau. To promote sustainable development in the world’s third pole, it is necessary to investigate population migration on the Plateau. Using 2010 census data, a spatial database of county-level migrants on the Plateau was constructed, and migrants were divided into short-distance and long-distance migrants according to the hukou-registered origins. Measuring migration intensity allowed the spatial pattern of population migration on the Plateau to be ascertained. The driving factors were identified using spatial regression models, and the main conclusions are as follows: (1) In 2010, there were 1.23 million inter-county migrants on the Qinghai-Tibet Plateau, and the overall migration intensity reached 10.50%. There existed significant spatial differences in population migration intensity on the Plateau at that time, and the provincial or prefectural capitals were attractive destinations for migrants. Northwestern Qinghai, which boasted mining industries, constituted a significant spatial cluster with a relatively high migration intensity. However, most areas on the Plateau attracted relatively few migrants, especially in western and northern parts of Tibet, which were sparsely populated and uninhabitable. (2) There were 0.95 million short-distance migrants and 0.28 million long-distance migrants. The short-distance migration intensity was 8.14%, while the long-distance migration intensity was only 2.36%. Short-distance migration was the main form of population migration, with a pattern similar to the layout of overall population migration intensity. Only a few county-level units strongly attracted long-distance migrants, which were mostly distributed in northwestern Qinghai. (3) Economic factors were considered fundamental drivers for migrants to live on the Plateau. Destinations with high levels of economic development and more opportunities in non-agricultural jobs proved more attractive for migrants. For short-distance migrants, urbanization level also proved a considerable driving factor for in-migration. However, long-distance migrants were mainly affected by the job chances of the secondary industry on the Qinghai-Tibet Plateau.
Human migration between cities is one important aspect of spatial interaction that not only reflects urban attractiveness but also denotes interactions amongst agglomerations. We therefore implemented a web-based visualization system to analyze and interactively explore local and distant population flow patterns between cities on the Qinghai-Tibet Plateau (QTP). We utilized 2017 Tencent population flow data from which we initially constructed inbound and outbound vectors for cities on the QTP. We then used multidimensional scaling to examine and visualize migration patterns and similarities between cities. Results reveal the presence of six local and three distant human mobility patterns on the QTP as well as average summer monthly migrations more than twice the level of those in the winter.
The cultivation and development of modern metropolitan areas with the aim of establishing new regional centers with competitive edge is a key objective for the new-type urbanization directions in China. The construction of the Lhasa Metropolitan Area is of great significance for the promotion of the South Asia Channel, the ‘Belt and Road’ initiative, the Bangladesh-China-India-Myanmar Economic Corridor, the Himalaya Economic Cooperation Zone, and for rapid development and long-term stability of the Qinghai-Tibet Plateau. This paper examines the scope of the Lhasa Metropolitan Area including Chengguanqu (Chengguan District), Doilungdeqen, Dagze, Lhunzhub, Damxung, Nyemo, Quxu, Maizhokunggar, Samzhubze Qu (Samzhubze District), Gyangze, Rinbung, Bainang, Nedong, Gonggar, and Zhanang using a spatial field energy model that combines nodality and accessibility indices and considers multiple indicators including traffic flow between cities. By combining factors such as the natural background, population agglomeration, the social economy, infrastructure construction, and the urban spatial structure of the Lhasa Metropolitan Area, it is proposed to build a bow-and-arrow-shaped urban system with ‘one core, two centers, one axis, and two wings’ along the valleys and the transportation trunk lines of the area. The study advocates the construction of a pure land industrial system comprising a green cultural and tourism-oriented plateau.
Based on a total of 519 images, the composite images with the lowest possible cloud cover were generated at pixel level with image synthesis method on Google Earth Engine (GEE) platform. The Remote Sensing Ecological Index (RSEI) was adopted, and calculated in an efficient way with the assistance of parallel cloud computing of the GEE platform. The RSEI was used in this paper to evaluate and monitor the eco-environmental quality of the Lhasa Metropolitan Area. Results show that: (1) The ecological quality is better in the west than in the east of Lhasa Metropolitan Area, with Lhasa as an approximate dividing point. The ecological quality improved and then deteriorated dramatically before 2000, with the mean RSEI value dropping from 0.51 to 0.46; the trend was followed by a gradual increase up until 2017, with the mean RSEI value increased from 0.46 to 0.55. (2) The RSEI is weakly and positively correlated with socioeconomic indicators. This indicates that the population growth and economic development did not negatively influence the ecological quality, but actually boosted it. (3) The GEE can serve as an efficient computing platform for the assessment and monitoring of eco-environmental quality in vast regions.
The Yarlung Zangbo River Basin (YZRB) is a key ecological protection area on the Qinghai-Tibet Plateau (QTP). Determination of the ecosystem service values (ESVs) can help recognize the benefits of sustainable management. It is gradually becoming the main path that constructs plateau spatial planning of integrating ecological protection, and achieves global sustainable development goals (SDGs) in China. In this paper, the spatio-temporal dynamic evolutions of the ESVs were estimated on the multiple scales of “basin, subbasin and watershed” from 1980 to 2015. The main factors influencing ESVs were explored in terms of physical geography, human activities, and climate change. It had been proposed that sustainable spatial planning including ecological protection, basin management, and regional development was urgent to set up. Our results show that the increase in wetland and forest and results in an increase of 9.4% in the ESVs. Attention should be paid to the reduction of water and grassland. Water conservation (WC), waste treatment (WT), and soil formation and conservation (SFC) are the most important ecosystem services in the YZRB. At present, the primary problem is to solve the ESVs decreasing caused by glacier melting, grassland degradation, and desertification in the upper reaches region. The middle reaches should raise the level of supply services. Regulation services should be increased in the lower reaches region on the premise of protecting vegetation. The ESVs in adjacent watersheds are interrelated and the phenomenon of “high agglomeration and low agglomeration” is obvious, existing hot-spots and cold-spots of ESVs. Additionally, when the altitude is 4500-5500 m, the temperature is 3-8°C, and the annual precipitation is 350-650 mm, ESVs could reach its maximum. A framework of sustainable plateau spatial planning could provide references to delimit the ecological protection red line, key ecological function zone, and natural resource asset accounting on the QTP.
A scientific evaluation of the broad reciprocal influences between urbanization and the eco-environment in the Tibetan Plateau region is of great significance for increasing the speed and quality of urbanization as well as restoring and improving the eco-environment. Based on a thorough look at the progress made by research on interactions between urbanization and the eco-environment in the Tibetan Plateau region, this article attempts to construct a complete analytical model of the reciprocal influences that can achieve the whole process of analyzing evaluation indexes, quantifying coupling coordination, identifying coupling types, exploring decoupling paths, and predicting future trends. Using multi-scale analysis of the Tibetan Plateau and its provinces and prefecture-level units as a means of comparison, we attempt to clarify differences at different scales, identify problem areas and propose targeted improvement measures. The result shows that the urbanization evaluation indexes for the Tibetan Plateau at different scales rise in stages and that the urbanization index for Qinghai is higher than for Tibet; the changes in the eco-environment index of the two regions are also different, with a downward trend in Qinghai and a trend toward stability in Tibet, and with stratification in the eco-environment indexes of prefecture-level units; the degree of coupling coordination between urbanization and the eco-environment at different scales in the Tibetan Plateau region is increasing overall, with the type of coordination changing from uncoordinated deterioration to borderline uncoordinated deterioration, and ultimately changing into scarcely coordinated development, which basically puts the region into the logging urbanization category; and the urbanization and eco-environment indexes display a dynamic trend of alternating between strong decoupling and weak decoupling, indicating that there is a negative reciprocal influence between urbanization and eco-environment at different scales and that the phenomenon of passive urbanization is prominent. We predict that in the next 10 years, the system coupling coordination of prefecture-level units in the Tibetan Plateau region will steadily increase, but there will be significant discrepancies in the growth rates of different regions.
