Estuaries provide many ecosystem services and host a majority of the world’s population. Here, the response of microbial communities after a record-breaking flood event in a highly urbanized estuary was followed. Hurricane Harvey (hereafter Harvey) was a category 4 hurricane that made landfall on the Texas coast in 2017 and lashed the Houston area with 1.4–1.7 × 1010 m3 of rainfall, disrupting the natural gradients of nutrients and salinity. Here, we utilized metagenomics to analyze how Harvey altered the microbial community of Galveston Bay over five weeks following the storm. We hypothesized that the community would shift from a marine dominated community to that of a terrestrial and freshwater origin. We found that following the storm there were changes in the distribution of species with specific metabolic capacities, such as Cyanobacteria, enriched in oxygenic photosynthesis and nitrogen fixation genes, as well as Verrucomicrobia and Betaproteobacteria, with high prevalence of the SOX complex and anoxygenic photosynthesis genes. On the other hand, dominant members of the community with more diverse metabolic capabilities showed less fluctuations in their distribution. Our results highlight how massive precipitation disturbances can alter microbial communities and how the coalescence of diverse microorganisms creates a resilient community able to maintain ecosystem services even when the system is in an altered state.
Intense rainfall from tropical cyclones has the potential to induce coastal acidification, which will become more common and severe as climate change continues. We collected carbonate chemistry samples from Galveston Bay, Texas before and after Hurricane Harvey in 2017 and 2018. Here, we show ecosystem level acidification and calcium carbonate undersaturation in Galveston Bay following the storm. This acidification event, driven by extreme rainfall from Harvey, persisted for over 3 weeks because of prolonged flood mitigation reservoir releases that continued for over a month after the storm. In addition, the large volume of stormwater led to high oyster mortality rates in Galveston Bay and acidification may have impeded recovery of these vital reefs. It is also likely that undersaturation has occurred outside of our study, unrecorded, following other high-rainfall storms. The projected increase in tropical cyclone rainfall under climate change may thus represent a significant threat to coastal calcifying ecosystems.
more » « less- NSF-PAR ID:
- 10382257
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Communications Earth & Environment
- Volume:
- 3
- Issue:
- 1
- ISSN:
- 2662-4435
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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