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bioRxiv · 10.1101/2021.09.10.459852

Modeling the underlying environmental factors of milky sea case and luminous bacteria presence in Java Southern Sea in 2019

Wibowo, A. A.
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Abstract

The milky sea is one of the unique natural phenomena caused by the presence of luminous Vibrio bacteria in marine ecosystems. Recently a milky sea has been reported frequently included in the Java Southern Sea. Simultaneously, numerous remote sensing based approaches have been developed to detect the presence of luminous bacteria and the milky sea. Despite this state of the art, the information of detrimental factors of the marine bioluminescence was still limited. Then this research aims to model the underlying environmental factors causing the milky sea and luminous bacteria presence in the Java Southern Sea in 2019. The remote sensing assessment for the period of July 29-August 6, 2019 shows that the magnitude of bioluminescence measured in radiance was having a maximum value of 255 nanoW/cm2/sr and an average of 107 nanoW/cm2/sr/day (95%CI: 71.9 to 142 nanoW/cm2/sr/day). The milky sea size increased and reached its peak with a size of 44,124 km2 and then declined. The average milky sea size was 37,942 km2 (95% CI: 33,400 to 42,500 km2) and increased with average rate of 16.01% (95%CI: 5.41% to 26.66%). While Akaike Information Criterion (AIC) indicates that the best model to infer the relationship of bacterial bioluminescence with its environmental factors contained Chlorophyll a followed by sea surface temperature factors with AICc values of 101.16 (AICweight: 0.50) and 101.95 (AICweight: 0.34). This indicates that low temperature and high plankton cells is the limiting factors of the bacterial bioluminescence.

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Wibowo, A. A.. 2021-09-11. Modeling the underlying environmental factors of milky sea case and luminous bacteria presence in Java Southern Sea in 2019. https://doi.org/10.1101/2021.09.10.459852

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