Add link to preprint

README.md

@@ -5,10 +5,10 @@ This repository has QIIME 2 compatible files, metadata, R Markdown files, and al
 **Assessing the effects of warming and carbonate chemistry parameters on marine microbes in the Gulf of Mexico through basin-scale DNA metabarcoding**<br/>
 *Sean R. Anderson, Katherine Silliman, Leticia Barbero, Fabian A. Gomez, Beth A. Stauffer, Astrid Schnetzer, Christopher R. Kelble, and Luke R. Thompson, (2024)*
 
-* [Preprint](add link)
+* [Preprint](https://www.biorxiv.org/content/10.1101/2024.07.30.605667v1)
 
 ### 1. Summary
-Ocean acidification and warming threaten marine life, either directly or indirectly, which can lead to loss of biodiversity and negative impacts for marine ecosystems. The effects of carbonate chemistry parameters and temperature on diverse marine microbes remains unclear. Yet, it is important to consider microbes because they form the base of ocean food webs, mediate global carbon and nutrient cycles, and are potential indicators of environmental change. In large part, this disconnect is rooted in a lack of spatial sampling of microbes and environmental variables in many ocean basins, including the Gulf of Mexico (GOM). In this study, we collected DNA samples at the basin scale in the GOM as part of the fourth Gulf of Mexico Ecosystems and Carbon Cycle (GOMECC-4) cruise that sailed in the summer-fall of 2021. DNA samples were collected at 51 sites along 16 inshore-offshore transects and up to three depths per site that reflected the surface, deep chlorophyll maximum, and near bottom (481 total filters). DNA metabarcoding captured prokaryotes (16S V4-V5) and protists (18S V9) at previously unresolved spatial scales. Generalized linear models were used to reveal the effects of carbonate chemistry parameters, temperature, and other variables on group-specific relative abundance in the photic zone. Models supported prior physiological trends among certain microbes, like positive temperature effects on SAR11 and SAR86, as well as a negative response of *Prochlorococcus* to lower pH. New insights were observed for Syndiniales and Sagenista, ubiquitous protists that represent parasitic and herbivorous lifestyles. At the species level, picoeukaryotes like *Ostreococcus* sp. and *Gephyrocapsa huxleyi* were found to be indicator taxa of less buffered waters in the GOM at this time.
+Ocean acidification and warming threaten marine life, either directly or indirectly, which can lead to loss of biodiversity and negative impacts for marine ecosystems. The effects of carbonate chemistry parameters and temperature on diverse marine microbes remains unclear. Yet, it is important to consider microbes because they form the base of ocean food webs, mediate global carbon and nutrient cycles, and are potential indicators of environmental change. In large part, this disconnect is rooted in a lack of spatial sampling of microbes and environmental variables in many ocean basins, including the Gulf of Mexico (GOM). In this study, we collected DNA samples at the basin scale in the GOM as part of the fourth Gulf of Mexico Ecosystems and Carbon Cycle (GOMECC-4) cruise that sailed in the summer-fall of 2021. DNA samples were collected at 51 sites along 16 inshore-offshore transects and up to three depths per site that reflected the surface, deep chlorophyll maximum, and near bottom (481 total filters). DNA metabarcoding captured prokaryotes (16S V4-V5) and protists (18S V9) at previously unresolved spatial scales. Generalized linear models were used to reveal the effects of carbonate chemistry parameters, temperature, and other variables on group-specific relative abundance in the photic zone. Models supported prior physiological trends among certain microbes, like positive temperature effects on SAR11 and SAR86, as well as a negative response of *Prochlorococcus* to lower pH. New insights were observed for Syndiniales and Sagenista, ubiquitous protists that represent parasitic and herbivorous lifestyles. At the species level, picoeukaryotes like *Ostreococcus* sp. and *Emiliania huxleyi* were found to be indicator taxa of less buffered waters in the GOM at this time.
 
 ### 2. Bioinformatics
 Code for 16S and 18S datasets are available in the `code` folder.