my country's mountainous and hilly areas account for about 65% of the country's land area, and the geological conditions are complex, making it difficult to prevent geological disasters. At present, there are 300,000 proven geological hazards in my country, threatening the lives of about 20 million people and 450 billion yuan of property. Therefore, investigating and identifying hazard bodies is a crucial task.
However, in the detailed investigation of geological disasters, there are usually three major problems:
1. The hidden danger points of major geological disasters are basically located in the middle and upper part of the mountain, with high and steep slopes, making it difficult for people to reach.
2. The dense vegetation leads to the coverage of hidden danger points, which are difficult to find by traditional means.
3. There are various disasters, and the signs of disasters are complicated, and it is difficult to identify them by a single method.
Using LiDAR technology can effectively solve the above problems: After removing vegetation by using LiDAR data, the obtained digital surface/elevation model (DSM/DEM) will expose various mountain damage and loose accumulations covered by vegetation, In this way, we can clearly and intuitively check the collapsed loose accumulation bodies covered by vegetation, large shattered mountain cracks, and signs of landslide deformation and damage, and can quickly and effectively identify hidden dangers of geological disasters.
The advantages of lidar in the detailed investigation of geological disasters are as follows:
1. Active, all-weather: not affected by light, it can work around the clock, and the drone can be carried flexibly. 2. High density and high efficiency: the dot density exceeds 100 dots/m2, and the DEM production efficiency is high.
2. Strong penetration and high precision: The multi-echo technology of lidar can penetrate vegetation and obtain accurate terrain information.
4. Multi-source data fusion: Obtain topographic information together with remote sensing technology (InSAR) and photogrammetry technology, and conduct a more comprehensive and scientific comprehensive assessment of the topography and landform of disaster sites through the superposition and fusion of multi-source data.
The application of laser radar technology in the detailed investigation of geological disasters can make data collection convenient and efficient, save a lot of costs in field work and data editing and processing, and at the same time greatly improve safety and make management of results more efficient. In addition, according to the application mode of lidar in the detailed investigation of land disasters, it is also extended to the fields of discovery and protection of disaster hazards along highways, railways, power lines, and pipelines, protection of hydropower stations, and emergency relief.