5:15 PM - 6:30 PM
[SCG45-P19] Technical protocol for deep-sea environmental monitoring by the portable seafloor observation platform Edokko Mark 1
Keywords:seafloor monitoring, deep-sea environments, environmental impact assessment
The mooring, lander, and cable connected station are conventional methods for deep-sea monitoring. Recently, increasing interest for seabed mining, requirement of environmental management, and demand for marine biodiversity raises the issue of seafloor monitoring techniques, especially for deep-sea environments. The portable seafloor observation platforms with standalone operation mechanisms have been developed. In Japan, the joint project of private companies and academia developed the portable seafloor observation platform Edokko Mark 1, consisting of grass spheres with a built-in HD video cameras system and an acoustic release mechanism (1). The Edokko Mark 1 has four types with unique abilities to adopt monitoring targets; HSG for anti-corrosion, 365 for long-term observation, COEDO for simple operation by human power. These products are commercially available from Okamoto Glass Co. Ltd. (https://ogc-jp.com/productinfo/glassball/).
The system of Edokko Mark 1 has been improved in the Japan projects for technology development on seabed mining. Since the trial to 8000m depth of Japan trench in 2013, the Edokko Mark 1 has been deployed on the seafloor of Okinawa Trough from 2014 to18 and off Minami Torishima from 2018 to 2021. The video image is commonly used for biological and ecological survey in deep-sea expedition, although the observation area is limited within lighting power. The hydrophone is an optional sensor of Edokko Mark 1, can record biological sound as well as anthropogenic and geological sources. The soundscape is complementary to image data, and enables the expand observation area for deep-sea communites. Electromagnetic current meter and acoustic current meter could be installed on Edokko Mark 1 at 1.5m position from the seafloor and measured bottom current. Another observation of 2019 in the Suruga Bay recorded deep-sea turbidity current triggered by heavy precipitation of the Super Typhoon Hagibis (2). In this case, a deep-water displacement phenomenon was determined and drastic turbidity change was quantified from video images.
The projects of marine environmental assessment anticipate the transportability and quick deployment capability of the portable seafloor observation platform such as Edokko Mark 1. The guidance for environmental impact assessment on seabed mining (ISBA/25/LTC/6/Rev.1) published by the International Seabed Authority recommends the Edokko Mark 1 as a suitable system adopted deep-sea observation protocol (https://www.isa.org.jm/). These knowledge on video observation strongly supported establishing the technical protocol and making the International Standard (ISO /DIS23730, 23731).
In this presentation we will explain the observation techniques and results from deep-seafloor surveys.
References:
1) Miwa, T., et al. 2016. Underwater Observatory Lander for the Seafloor Ecosystem Monitoring using a Video System. Pages 333-336 in Techno-Ocean. IEEE, Kobe.
2) Kawagucci, S., et al. 2020. Deep-sea water displacement from a turbidity current induced by the Super Typhoon Hagibis. PeerJ 8:e10429.
The system of Edokko Mark 1 has been improved in the Japan projects for technology development on seabed mining. Since the trial to 8000m depth of Japan trench in 2013, the Edokko Mark 1 has been deployed on the seafloor of Okinawa Trough from 2014 to18 and off Minami Torishima from 2018 to 2021. The video image is commonly used for biological and ecological survey in deep-sea expedition, although the observation area is limited within lighting power. The hydrophone is an optional sensor of Edokko Mark 1, can record biological sound as well as anthropogenic and geological sources. The soundscape is complementary to image data, and enables the expand observation area for deep-sea communites. Electromagnetic current meter and acoustic current meter could be installed on Edokko Mark 1 at 1.5m position from the seafloor and measured bottom current. Another observation of 2019 in the Suruga Bay recorded deep-sea turbidity current triggered by heavy precipitation of the Super Typhoon Hagibis (2). In this case, a deep-water displacement phenomenon was determined and drastic turbidity change was quantified from video images.
The projects of marine environmental assessment anticipate the transportability and quick deployment capability of the portable seafloor observation platform such as Edokko Mark 1. The guidance for environmental impact assessment on seabed mining (ISBA/25/LTC/6/Rev.1) published by the International Seabed Authority recommends the Edokko Mark 1 as a suitable system adopted deep-sea observation protocol (https://www.isa.org.jm/). These knowledge on video observation strongly supported establishing the technical protocol and making the International Standard (ISO /DIS23730, 23731).
In this presentation we will explain the observation techniques and results from deep-seafloor surveys.
References:
1) Miwa, T., et al. 2016. Underwater Observatory Lander for the Seafloor Ecosystem Monitoring using a Video System. Pages 333-336 in Techno-Ocean. IEEE, Kobe.
2) Kawagucci, S., et al. 2020. Deep-sea water displacement from a turbidity current induced by the Super Typhoon Hagibis. PeerJ 8:e10429.