An in-situ portable pore-water sampler for evaluating the vertical distribution in the sediment interface

Abstract

The characteristics of chemical elements in marine pore-water are significant for investigating and evaluating the marine sediment environment (especially vertical distribution characteristics, etc.). Therefore, sampling high-quality pore-water is necessary for marine scientific research. This paper proposes an in-situ portable pore-water sampler that utilizes the compression spring structure, allowing the potential energy generated by the spring to be converted into kinetic energy for the sampling process. The sampler requires no other power and can be portable for marine pore-water sampling. We first described the sampler’s mechanical design, which can obtain one sediment-overlying water and three sediment pore-water samples at different depth profiles. Secondly, to judge the force state of the power spring, we designed laboratory experiments and simulation tests based on COMSOL Multiphysics to analyze the force during the working process of power springs. Finally, we deployed the sampler offshore in Zhoushan Islands for actual sampling, and we tested and compared the in-situ samples with the centrifugal samples to analyze the vertical distribution of chemical elements. The successful sea trials verified the reasonableness of the mechanical design, theoretical calculation and experimental analysis of the sampler. Furthermore, we will continue to optimize the sampler and apply it more widely.