Background Corals, which form the foundation of biodiverse reef ecosystems, are under threat from warming oceans. Reefs provide essential ecological services, including food, income from tourism, nutrient cycling, waste removal, and the absorption of wave energy to mitigate erosion. Here, we studied the coral thermal stress response using network methods to analyze transcriptomic and polar metabolomic data generated from the Hawaiian rice coral Montipora capitata . Coral nubbins were exposed to ambient or thermal stress conditions over a 5-week period, coinciding with a mass spawning event of this species. The major goal of our study was to expand the inventory of thermal stress-related genes and metabolites present in M. capitata and to study gene-metabolite interactions. These interactions provide the foundation for functional or genetic analysis of key coral genes as well as provide potentially diagnostic markers of pre-bleaching stress. A secondary goal of our study was to analyze the accumulation of sex hormones prior to and during mass spawning to understand how thermal stress may impact reproductive success in M. capitata . Methods M. capitata was exposed to thermal stress during its spawning cycle over the course of 5 weeks, during which time transcriptomic and polar metabolomic data were collected. We analyzed these data streams individually, and then integrated both data sets using MAGI (Metabolite Annotation and Gene Integration) to investigate molecular transitions and biochemical reactions. Results Our results reveal the complexity of the thermal stress phenome in M. capitata , which includes many genes involved in redox regulation, biomineralization, and reproduction. The size and number of modules in the gene co-expression networks expanded from the initial stress response to the onset of bleaching. The later stages involved the suppression of metabolite transport by the coral host, including a variety of sodium-coupled transporters and a putative ammonium transporter, possibly as a response to reduction in algal productivity. The gene-metabolite integration data suggest that thermal treatment results in the activation of animal redox stress pathways involved in quenching molecular oxygen to prevent an overabundance of reactive oxygen species. Lastly, evidence that thermal stress affects reproductive activity was provided by the downregulation of CYP-like genes and the irregular production of sex hormones during the mass spawning cycle. Overall, redox regulation and metabolite transport are key components of the coral animal thermal stress phenome. Mass spawning was highly attenuated under thermal stress, suggesting that global climate change may negatively impact reproductive behavior in this species.
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This content will become publicly available on October 6, 2024
Ultraporous superactivated hydrochars from food waste: comparing environmental impacts of char impregnation versus direct chemical activation method
The monumental challenge associated with food waste management has emphasized the dire need of upcycling it into useful materials, including ultraporous adsorbent. Among various technologies of maximizing porosity of such waste-derived porous sorbents, potassium hydroxide (KOH) activation of food waste hydrochar has emerged to be a prominent one. There are two different ways to synthesize ultraporous adsorbent, namely, direct chemical activation (DCA) and char impregnation (CI). This study aims in investigating the environmental impact comparison of DCA and CI using life cycle assessment (LCA). The results demonstrate that CI processes in an environmentally sound way for synthesizing ultraporous carbons from food waste, where freshwater ecotoxicity (57.2%) plays the major contributing role in environmental impact category, primarily due to acid neutralization in the mixer unit of the CI technique of activation. In addition, the dryer unit in the CI process, which is powered by natural gas combustion, was responsible for climate change impact category. Therefore, as an alternative, employment of renewable solar energy (from solar thermal power plant) was also investigated, and results highlighted the possibility of achieving reduced climate change and acidification potential.
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- Award ID(s):
- 2123495
- NSF-PAR ID:
- 10475647
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Biomass Conversion and Biorefinery
- ISSN:
- 2190-6815
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Location 1700‐km Eurasia Arctic Transect (EAT), Yamal Peninsula and Franz Josef Land (FJL), Russia.
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