Seamount refers to the uplift that is more than 1000 meters high from the seabed, but still does not protrude from the sea level. Seamounts are similar to ridges on land and the typical seamounts are formed by dead volcanoes. It is estimated that there are more than 30000 seamounts in the global ocean, more than 60% of which are distributed in the Pacific Ocean. According to reports, the main feature of seamounts is that they are rich in marine biodiversity. Understanding rare suspended particulate matter (including planktonic microorganisms) in the seamount is important but difficult to sample, for which we deigned a large-sized in-situ water sampler (200—1000L), i.e., a large volume water transfer and graded filtration system. The system comprises of a deep-sea pump assemble, a filtering device, data acquisition and control devices, a supporting frame, a power supply component, a connecting mechanism, and a flow meter, etc. The filtering device integrates membranes for three-graded filtration at 0.22, 1, and 5μm. The system has been applied for high-level multi-layer filtration to obtain planktonic microorganisms in tropical western Pacific seamounts of Yap seamount and Caroline seamount. The applications of the large volume water in-situ transfer in the seamounts practice show: The in-situ filtration completed by large volume water transfer system is an effective method, which has much more efficiency and simplicity than traditional method of taking water out and filtrating on deck. In situ filtration of the large volume water transfer system is of great significance in reducing the real community structure of deep-sea microorganisms. The deeper the sampling depth, the greater the loss caused by traditional methods, and this loss is biased, which will lead to the loss of nearly 50% of microbial species.

Yonghua Chen, Hegang Hu, Qingkui Liu, Bin Jiang. Application of the IOCAS Large Volume Water Transfer System in the Research of the Tropical Western Pacific Seamounts. Academic Journal of Engineering and Technology Science (2021) Vol. 4, Issue 7: 51-56. https://doi.org/10.25236/AJETS.2021.040709.

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