Development on a New Type of Marine Plankton Temperature-Retained and Pressure-Retained Sampler

The marine plankton temperature-retained and pressure-retained sampler is an innovative, deep-sea (maximum 6,000 m) sampler that is equipped with three trawls to obtain marine plankton samples at specified depths and with simultaneous collection of sensor data. The sampler can collect plankton horizontally near the seabed or vertically at different levels of water driven by an underwater fluid power system. The sampler is equipped with a temperature-retained and pressure-retained system to keep the obtained plankton alive when it is brought to the deck, which improves the effective sampling rate of the sampler. The sampler can be monitored in real time and controlled from the deck via a coaxial cable, such that operators onboard can choose the proper sampling location, control the attitude and the moving speed of the sampler, and collect pressure-retained plankton samples in different depths during one deployment. In its verification deployment in the South China Sea (longitude 111°11′´E, latitude 18°05′), the sampler was operated three times at depths of 1,200, 1,500, and 1,600 m. Some plankton samples with in-situ pressure retained have been successfully obtained and the pressure did not decrease after 24 h.