Abstract:
Recent studies have shown an increase or even outbreaks of jellyfish in many bays and seas around the world, which has a negative impact on the marine ecological environment, marine fisheries, coastal tourism, nuclear safety and so on. In August 2017, the self-developed shipborne polarized oceanic lidar carried out experimental measurements in the Yellow Sea. Rich strongly scattered individual signals were observed. Combined with the video monitor information, the signals were determined to come from the jellyfish (Nemopilema nomurai), demonstrating the polarized oceanic lidar is available to realize the remote sensing detection of jellyfish. The results show that the optical properties of jellyfish in the same waters show clustering. The signal contrast distribution of jellyfish in different waters was similar, and the distribution of depolarization rate was different, indicating that the optical properties of jellyfish were closely related to the water environment where they lived. As a result, the polarized oceanic lidar can monitor the distribution and population changes of jellyfish efficiently, economically and accurately and its future promotion can improve the dynamic monitoring methods of jellyfish in Chinese waters.