Articles | Volume 21, issue 5
https://doi.org/10.5194/os-21-2379-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-21-2379-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Phytoplankton detection study through hyperspectral signalling in the Patagonian fjords
Pilar Aparicio-Rizzo
CORRESPONDING AUTHOR
Centro i-mar, Universidad de Los Lagos, Puerto Montt, Chile
Centro del Clima y la Resiliencia (CR)2, Santiago de Chile, Chile
Dagoberto Poblete-Caballero
Centro i-mar, Universidad de Los Lagos, Puerto Montt, Chile
Cristian Vera-Bastidas
Centro i-mar, Universidad de Los Lagos, Puerto Montt, Chile
Iván Pérez-Santos
Centro i-mar, Universidad de Los Lagos, Puerto Montt, Chile
Centro i-mar, Universidad de Los Lagos, Puerto Montt, Chile
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EGUsphere, https://doi.org/10.5194/egusphere-2025-4807, https://doi.org/10.5194/egusphere-2025-4807, 2025
This preprint is open for discussion and under review for Ocean Science (OS).
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Submarine canyons are known hotspots of marine productivity and biodiversity, but we do not fully understand why. We studied a submarine canyon located in central Chile and found that it is a highly dynamic environment in both space and time. We think that the alternating currents and the contrasting distribution of zooplankton within the canyon might interact to promote zooplankton retention. Our results help to explain why submarine canyons host such high zooplankton diversity and abundance.
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Marine heatwaves and cold spells are periods of extreme sea temperatures. This study focuses on Chilean Northern Patagonia, a fjord region vulnerable due to its aquaculture. It aims to understand these events' distribution and identify the most affected basins. Results show higher intensity in enclosed areas like Reloncaví Sound and Puyuhuapi Fjord. Marine heatwaves are becoming more frequent over time, while cold spells are decreasing.
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Biogeosciences, 21, 1433–1459, https://doi.org/10.5194/bg-21-1433-2024, https://doi.org/10.5194/bg-21-1433-2024, 2024
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The Patagonian fjords comprise a world region where low-oxygen water and hypoxia conditions are observed. An in situ dataset was used to quantify the mechanism involved in the presence of these conditions in northern Patagonian fjords. Water mass analysis confirmed the contribution of Equatorial Subsurface Water in the advection of the low-oxygen water, and hypoxic conditions occurred when the community respiration rate exceeded the gross primary production.
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Short summary
This work combines a hyperspectral sensor and an unmanned aerial vehicle to detect and differentiate phytoplankton species from optical data in Patagonian fjords at local scale. The results show differences between in situ spectral signals, especially in the blue, green and red near-infrared spectra, distinguishing between diatom and dinoflagellate. These tools are useful especially in coastal areas where cloud cover and geographical heterogeneity make satellite data acquisition difficult.
This work combines a hyperspectral sensor and an unmanned aerial vehicle to detect and...