LAPIS: A new imaging tool for macro-zooplankton

摘要

Accurate sampling of macrozooplankton and micronekton has always been challenging. The organisms are often sparse and patchy, and can sometimes detect oncoming nets and avoid capture. Gelatinous zooplankton are particularly difficult to sample. Some are so fragile that they are destroyed in the net, while others may be so abundant that they clog nets. As an alternative sampling approach, camera systems can obtain images of particles or plankton in a quantitative fashion. However, plankton-imaging devices built to date operate at too small a spatial scale to be useful for macrozooplankton and micronekton, which range in size from 1 cm to 1 m, with varied shapes, transparency and reflectivity. We have designed and built the Large Area Plankton Imaging System (LAPIS) to address this gap in current imaging capabilities. LAPIS uses hardware and software similar to the Video Plankton Recorder [1] but illuminates much larger volumes in order to image macroplanktonic organisms, including crustaceans, fish and gelatinous animals. This paper briefly describes the current instrument, which was first used on a research cruise in February and March, 2006, and summarizes it capabilities and potential, with examples of image data and their interpretation.