■ Background and Necessity
● Global problems are occurring due to climate warming, population growth, and urbanization.
- Climate change and population growth (8.7 billion people in 30 years, 9.7 billion people expected in 50 years) act as a burden on the global food production system
- Due to urban expansion, problems such as forest disappearance, biodiversity loss, and urban micro-climate change occur
● With the development of remote sensing technology and analysis technology such as deep learning, various solutions are being sought.
- Strengthen monitoring and promote precision agriculture through the operation of remote sensing satellites
- Searching for solutions by developing new satellite image analysis techniques using deep learning
● Korea also responds to changes through the development and operation of next-generation medium-sized satellites (land, agriculture, water resources, etc.)
- Therefore, it is necessary to understand international research trends and issues related to the use of satellite information in the field of land (agriculture, forestry, water resources, cities, coasts, etc.)
■ Research method
● Bibliographic analysis
- Used DB and analysis tools: SCOPUS, SciVal (2022)
- Analysis period: 2020 ~ 2022
- Contents of analysis: Research topic, current status of research cooperation, major countries and major research institute paper indicators
● Summary of research trends: authors, research contents, research results, keywords
■ Current status of research
● Major research countries: China, USA, Spain in order. There are no authors of review papers in the field of land in Korea.
● Major research institutes: Chinese Academy of Sciences has the most with 6
● Major research topics: NDVI-phenomenology-climate change, change detection-remote monitoring image-SAR, hyperspectral image-spectroscopy-image classification, etc.
■ Research trends in the use of satellite information in the field of land
● Research trends by sector
- Agriculture: remote sensing for precision agriculture, soil salinity monitoring, land monitoring, etc.
- Forestry: remote sensing of forest phenomenology, monitoring of cover and use, remote sensing of mine ecological restoration, remote sensing of tropical forests, etc.
- Water resources: drought remote sensing, flood risk analysis and evaluation, data assimilation for mountain snow cover estimation, data assimilation for seasonal snow estimation, evapotranspiration observation, modeling and satellite-based estimation, soil moisture content remote sensing using GNSS-R, water ・Heat circulation, etc.
- City: city information extraction, urban green space and vegetation fragmentation, etc.
- Coast: Coastal area analysis using L-band SAR, coastal erosion prediction evaluation, etc.
- Others: hyperspectral image classification, ground change map classification, multispectral-based change detection, pasture, road, malaria, etc.
● Analysis method
- Random forest (RF), maximum likelihood classification (MLC), pixel-based (PB) and object-based image analysis (OBIA), principality analysis (PCA), support vector machine (SVM), support vector regression (SVR), convolution Neural network (CNN), generative adversarial network (GAN), canonical correlation forest (CCF), multivariate analysis, linear discriminant analysis, spectral index, cloud-based computing, inverse forest reflection model, UAV data and convergence, etc.
■ Policy Implications
● Need to respond to rapid development of earth observation and image analysis technology
- Research on convergence methods that can be linked with other satellite images as well as other observation data, continuous exchanges and cooperation with institutions and personnel with the best technology, and training of related experts are required.
● Demand for infrastructure expansion to vitalize the use of satellite information by industry, academia, and research
- In order to encourage industry-university-institute participation, it is necessary to establish and service a big data platform that supports the production of additional data using innovative pricing policies, standard images and outputs, guarantee stable and continuous satellite operation, and prepare grounds for supporting private companies.
● Need to prepare for climate change in terms of food security
- It is necessary to prepare for food security, such as continuous monitoring of major agricultural production areas overseas, domestic crop monitoring, response to disasters due to climate change, and preparation of coastal erosion measures.