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The Irrawaddy River is the largest river in Myanmar with its river delta as the country’s agricultural center. It is of great significance to investigate river channel erosion and ecosystem evolution in such a river delta based on remote sensing. Thus, its river channel erosion/deposition and ecosystem evolution from 1970s to 2011 were analyzed based on Landsat and HJ satellite data through object-oriented supervised classification with the NDVI and NDWI threshold segmentation methods were used. The results show that river channel of Irrawaddy River from Burma Aung to the estuary delta hardly changes in 34 years while area of the estuary shoal is increasing slowly. An overall trend of continuously enlargement of cultivated land and urban land is found in the delta area with a gradually reduced forest land and wet land.

In the summer of 2013, the Heilongjiang River basin witnessed its biggest floods since 1984. The once-in-a-century flood happened in its lower reaches and spread to a range of 950 km along the main channel, causing large area of farmland to be flooded and lots of houses to collapse. There were about 8.29 million people were affected. In this paper, wide and high frequency-featured HJ-1A/B satellite images were used to monitor this whole flooding process across time and space. Very good results were achieved and a practicable monitoring method based on HJ-1A/B data was established for the applications in the future.

Poyang Lake, the largest freshwater lake in China, is well known for its ecological importance as a wetland system.. Understanding dynamics change in wetlands may benefit from a joint variation analysis in changes of size, shape, position and extent of water bodies. In this study, we used Cosmo-Skymed ScanSAR mode (HH) data for one-year monitoring of seasonal changes in the water surface areas of Poyang Lake from January 2014 to December 2014. To delinate water surface area, a histogram analysis with a global threshold classification was performed, and the results were validated using Landsat8 OLI data. The results showed: Poyang Lake water body area showed a significant seasonal variation, minimum value was about 690 km2 and maximum value reached 3500 km2. A unique spatial pattern occurred during those months that a dramatic flooding or recession happened. The Cosmo-Skymed time series could capture temporal changes in the water body spatial distribution. Comparison of the resultant classification of Cosmo-Skymed and Landsat8 OLI yielded 95% of mapping accuracy and 87% of puduct accuracy. This demonstrates the X-band Synthetic Aperture Radar is applicable to detect the wetland inundation area and there is a great potential of Cosmo-Skymed constellation for water bodies monitoring, regarding relative great revisit frequency and high resolution.

As an important means of obtaining spatial data, the unmanned aerial vehicle (UAV) remote sensing has such advantages as real-time, flexible, high-resolution, cost-effective etc, and it can gather information in dangerous environments without risk to flight crews. Because UAV remote sensing is a powerful supplement of spaceborne remote sensing and airborne remote sensing, it has enormous potential and bright prospect. In this paper, the compositions and key technologies of UAV remote sensing system are presented, and the applications such as land use, land supervision, flood disasters, meteorology disasters, geological disasters, forest fire disasters as well as surveying and mapping are summarized. In the end, we predict the main direction of studying on UAV remote sensing in the future.