Hazards Assessment of Regional Debris Flows Based on Geographic Information Science

Supported by the spatial analysis feature of geographic information science and assessment model of regional debris flows, hazards degrees of the debris flows in the Upper Yangtze River Watershed （UYRW） are divided into five grades based on grid cell. The area of no danger, light danger, medium danger, severe danger and extreme severe danger regions respectively are 278 000, 288 000, 217 000, 127 000, 15 000 km^2. Furthermore, the counties in the UYRW are classified into four classes based on the hazards degrees in each county. The number of severe danger, medium danger, light danger and no danger counties respectively are 49, 82, 77 and 105. The assessment results will be provided for the hazards forecasting and mitigation in the UYRW and ongoing regionalization of Main Function Regions in China as data and technique framework.

Topography and human disturbances are major controlling factors in treeline pattern at Barun and Manang area in the Nepal Himalaya

The alpine treeline ecotone is an important component of mountain ecosystems of the Nepal Himalaya; it plays a vital role in the livelihood of indigenous people,and provides ecosystem services. However,the region faces a problem of paucity of data on treeline characteristics at the regional and landscape scales. Therefore,we used Remote Sensing(RS),and Geographic Information Science(GIS) approaches to investigate cross-scale interactions in the treeline ecotone. Additionally,European Space Agency land cover map,International Center for Integrated Mountain Development(ICIMOD) land cover map,ecological map of Nepal,and United States Geological Survey Shuttle Radar Topography Mission-Digital Elevation Model were used to analyze treeline pattern at the regional scale. Digital Globe high-resolution satellite imagery of Barun(eastern Nepal) and Manang(central Nepal) were used to study treeline patterns at the landscape scale. Treeline elevation ranges from 3300-4300 m above sea level. Abies spectabilis,Betula utilis,and Pinus wallichiana are the main treeline-forming species in the Nepal Himalaya. There is an east to west treeline elevationgradient at the regional scale. No slope exposure is observed at the regional scale; however,at the landscape scale,slope exposure is present only in a disturbed area(Manang). Topography and human disturbance are the main treeline controlling factor in Barun and Manang respectively.

Spatiotemporal analysis,hotspot mapping,and clustering of confirmed cases of COVID-19 in the initial phase of the pandemic in Qom province,Iran

Objective:To identify the incidence rate,relative risk,hotspot regions and incidence trend of COVID-19 in Qom province,northwest part of Iran in the first stage of the pandemic.Methods:The study included 1125 officially reported PCR-confirmed cases of COVID-19 from 20 February 2020 to 20 April 2020 in 90 regions in Qom city,Iran.The Bayesian hierarchical spatial model was used to model the relative risk of COVID-19 in Qom city,and the segmented regression model was used to estimate the trend of COVID-19 incidence rate.The Poisson distribution was applied for the observed number of COVID-19,and independent Gamma prior was used for inference on log-relative risk parameters of the model.Results:The total incidence rate of COVID-19 was estimated at 89.5 per 100000 persons in Qom city(95%CI:84.3,95.1).According to the results of the Bayesian hierarchical spatial model and posterior probabilities,43.33%of the regions in Qom city have relative risk greater than 1;however,only 11.11%of them were significantly greater than 1.Based on Geographic Information Systems(GIS)spatial analysis,10 spatial clusters were detected as active and emerging hotspot areas in the south and central parts of the city.The downward trend was estimated 10 days after the reporting of the first case(February 7,2020);however,the incidence rate was decreased by an average of 4.24%per day(95%CI:−10.7,−3.5).Conclusions:Spatial clusters with high incidence rates of COVID-19 in Qom city were in the south and central regions due to the high population density.The GIS could depict the spatial hotspot clusters of COVID-19 for timely surveillance and decision-making as a way to contain the disease.

Disciplinary structure and development strategy of information geography in China

The advent of the information era has resulted in exceptional advances in geographic science.The domain of geographic science has expanded from traditional physical and human geography to physical,human,and information geography,resulting in the emergence of the field of information geography.Three subdisciplines have gradually formed,i.e.,geographic remote sensing science,geographic information science,and geographic data science.With a view towards preparing a description of the disciplinary structure of geographic science for the“Development Strategy of Discipline and Frontier Research in China(2021-2035)”,this article summarizes the history,definition,and disciplinary structure of information geography.The strategic layout of the discipline,along with the goals and key directions of priority development fields,are also highlighted.The insights into this new discipline provided in this paper will promote the development and application of remote sensing and geographic information within the framework of geographic science,advancing the synthesis of geographic research and the integrated development of geographic science.

Core or edge? Revisiting GIScience from the geography-discipline perspective

As an inter-disciplinary area between geography and computer sciences, geographical information science(GIScience) inherits the spatial analysis tradition of the former. Together with other branches of information geography, it seeks the balance between universality and particularity of geographical laws by combining methods from neighboring disciplines(such as big data and artificial intelligence) with the special nature of geographical spaces. Meanwhile, at the core position of the geography discipline, GIScience makes geography stronger from two directions: "strengthening the theoretical foundation" and "improving technology and promoting the practical applications".

Geomorphology-oriented digital terrain analysis:Progress and perspectives

Digital terrain analysis(DTA)is one of the most important contents in the research of geographical information science(GIS).However,on the basis of the digital elevation model(DEM),many problems exist in the current research of DTA in geomorphological studies.For instance,the current DTA research appears to be focused more on morphology,phenomenon,and modern surface rather than mechanism,process,and underlying terrain.The current DTA research needs to be urgently transformed from the study of landform morphology to one focusing on landform process and mechanism.On this basis,this study summarizes the current research status of geomorphology-oriented DTA and systematically reviews and analyzes the research about the knowledge of geomorphological ontology,terrain modeling,terrain derivative calculation,and terrain analytical methods.With the help of DEM data,DTA research has the advantage of carrying out geomorphological studies from the perspective of surface morphology.However,the study of DTA has inherent defects in terms of data expression and analytic patterns.Thus,breakthroughs in basic theories and key technologies are necessary.Moreover,scholars need to realize that DTA research must be transformed from phenomenon to mechanism,from morphology to process,and from terrain to landform.At present,the research development of earth science has reached the critical stage in which the DTA research should focus more on geomorphological ontology.Consequently,this study proposes several prospects of geomorphology-oriented DTA from the aspects of value-added DEM data model,terrain derivatives and their spatial relations,and macro-terrain analysis.The study of DTA based on DEM is at a critical period along with the issue on whether the current GIS technology can truly support the development of geography.The research idea of geomorphology-oriented DTA is expected to be an important exploration and practice in the field of GIS.

Geoinformatics education in China

The paper gives an overview of the current status of education in geoinformatics in China.First,the paper provides a brief introduction to the history of geoinformatics education in China and a general review of the scientific and technological development.It then presents how the development affects the education and training in China.In the paper,universities and institutes in China that can award academic degrees related to geoinformatics are summarized,and undergraduate majors are briefly introduced.Next,the paper reports the work having been done by the national expert group on Surveying and Mapping,including the revision of discipline catalog and guide for graduate education and requirements.A list of typical curricula in geoinformatics education is suggested.Activities on promoting the graduate student exchange platform are presented.Finally,a case study of geoinformatics education in Wuhan University is discussed.