Although it is known that the Ross Sea is responsible for more than a quarter of CO2 absorption of the Southern Ocean, more information is needed to model the primary production of this key area. In particular, it is necessary to improve the characterization of the size class distribution, biomass and taxonomic composition of phytoplankton in the Ross Sea. Recently, an innovative compact lidar fluorosensor was deployed for real-time sensing of chlorophyll a, during the Ross Sea Mesoscale Experiment (RoME), conducted in the XXIX (2014) and XXXI (2016) Italian Antarctic expeditions. Furthermore, high-performance liquid chromatography (HPLC) was also performed to provide pigment analysis of in situ samples. Lidar fluorosensors are laser-induced fluorescence (LIF) instruments and have been extensively operated by the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) since the 1990s to monitor water bodies. Spectra obtained with LIF contain signatures of phytoplankton pigments, chromophoric dissolved organic matter and dispersed impurities, such as crude oils. The study of algal pigments provides not only the phytoplankton biomass—directly linked to chlorophyll a—but also its taxonomic composition through detection of several accessory pigments. Moreover, some models allow the identification of phytoplankton size classes. Lidar and HPLC mapped the spatiotemporal distribution of algal biomass and showed that during RoME, the phytoplankton assemblage structure was dominated by large-size cells (micro-phytoplankton) and the prevailing algal groups were diatoms.
|Titolo:||Lidar Monitoring of Chlorophyll a During the XXIX and XXXI Italian Antarctic Expeditions|
|Data di pubblicazione:||2019|
|Appare nelle tipologie:||1.1 Articolo in rivista|