A pneumatically-operated, submersible, three-dimensional water sampler for microscale studies

Laurent Seuront, Dominique Menu

Limnol. Oceanogr. Methods 4:260-267 (2006) | DOI: 10.4319/lom.2006.4.260

ABSTRACT: To determine how marine microorganisms locally interact, it is critical to assess their 3-dimensional distribution with microscale spatial sampling resolution and minimal disturbance. Here we describe a 3-dimensional syringe pump water sampling device that overcomes the constraints of previous 1- or 2-dimensional samplers. 3DMAPPER consists of a 1-m3 cubic stainless-steel structure supporting three 10-by-10 arrays of 60-mL syringes with an intersample distance of 5 cm. The design ensures a high stability of syringe sampling position and an undisturbed sampling volume for mean flow velocities ranging from 5 to 180 cm s–1. 3DMAPPER can easily be disassembled into subsections to simplify the handling of multiple samples, the syringes are easy to replace, and the sampling of multiple large volumes allows statistical treatment of multiple variables. The 300 syringes of 3DMAPPER are drained under water by increasing the ambient hydrostatic pressure using a SCUBA tank, and simultaneously and immediately filled upon relieving the inside pressure via a surface valve. 3DMAPPER is independent of a surface power supply and is deployed directly in the water to be sampled, making it versatile and appropriate for in situ deployment.