Physiological Responses of Pocillopora acuta and Porites lutea Under Plastic and Fishing Net Stress

Abstract

Marine debris has become a global problem affecting coral health around the globe. However, the photophysiological responses of corals to marine debris stress remain unclear. Therefore, this study firstly investigated transparent and opaque plastic bag shading and fishing nets directly contacting the coral. Photosynthetic performance, pigment content, symbiont density, and calcification rate of a branching coral Pocillopora acuta and a massive coral Porites lutea were investigated after 4 weeks of exposure to marine debris. The results show that the maximum quantum yield of PSII significantly decreased in P. lutea with all treatments, while P. acuta showed no effect on the maximum quantum yield of PSII from any treatments. Transparent plastic bag shading does not affect P. acuta, but significantly affected the maximum photochemical efficiency of P. lutea. Photoacclimation of cellular pigment content was also observed under opaque plastic bag shading for both species at week 2. Fishing nets had the strongest effect and resulted in P. acuta bleaching and P. lutea partial mortality as well as a decline in zooxanthellae density. Calcification rate of P. acuta significantly decreased with treatments using opaque plastic bag and fishing net, but for P. lutea only the treatment with fishing net gave any observable effects. This study suggests that the sensitivities of corals to marine debris differ strongly by species and morphology of the coral.

A new approach to classifying polymer type of microplastics based on Faster-RCNN-FPN and spectroscopic imagery under ultraviolet light

“…In addition, numerous studies on marine life have shown that fish that consume microplastics have early mortality, energy depletion, reproductive problems, behavioural issues, and gut obstructions. The impact of these microplastics also extends to marine ecosystems, such as seagrass meadows, mangroves, and coral reefs 5 , 13 .…”

Bacterial Communities Vary from Different Scleractinian Coral Species and between Bleached and Non-Bleached Corals

“…The health of the coral holobiont hinges on multiple external and internal factors. The former includes temperature changes ( 8 ), eutrophication ( 9 , 10 ), ocean acidification ( 11 ), and other anthropogenic environmental stresses (such as plastic pollution and overfishing) ( 12 ). All of these factors can destabilize the symbiosis between the host and their symbionts, leading to massive mortality and bleaching events ( 13 ).…”

Dominance of the coral Pocillopora acuta around Phuket Island in the Andaman Sea, Thailand

“…(2017). In the Andaman Sea, several authors refer to the prevalent species as P. damicornis (Brown et al., 2019; Kuanui et al., 2008; Phongsuwan & Chansang, 2012; Putchim et al., 2017) whereas others classify it as P. acuta (Rinkevich et al., 2016; Ying et al., 2021).…”

“…Pocillopora damicornis type γ (sensu Schmidt-Roach et al, 2013) corresponds to mtORF Type 3 (sensu Pinzón et al, 2013), Type NF (sensu Souter et al, 2009), as well as ORF 35-48 within the Primary Species Hypothesis PSH13 proposed by Gélin, Postaire, et al (2017). In the Andaman Sea, several authors refer to the prevalent species as P. damicornis (Brown et al, 2019;Kuanui et al, 2008;Phongsuwan & Chansang, 2012;Putchim et al, 2017) whereas others classify it as P. acuta (Rinkevich et al, 2016;Ying et al, 2021).…”