[Enviro-lunch] this Thursday (10/19): Jesse Wilson, "Complex microbial community interactions control carbon cycling along natural and experimental carbon and nutrient gradients in marine lakes"

[Lixia Jin]

[cid:35AD16B5-5C20-4F2C-BCD3-8BAC0F72CAFB at hsd1.ca.comcast.net.]
Dear all,
Please join us this Thursday for our speaker, Dr. Jesse Wilson from UC Merced.

Jesse Wilson
Environmental systems, UC Merced

Complex microbial community interactions control carbon cycling along natural and experimental carbon and nutrient gradients in marine lakes


Abstract: Collective interactions within microbial communities drive biogeochemical cycling of carbon (C) and nitrogen (N) but remain poorly understood: are biogeochemical shifts driven by a few keystone taxa, for instance, or do complex changes in community composition, diversity, and function occur? We assessed microbial communities and C-cycling rates across marine lakes in Palau—a natural experimental system with lakes differing in nutrient enrichment and stratification—and in experimental incubations. Multivariate analyses showed that low nutrient, unstratified lake communities (assessed via 16S rRNA gene sequencing) were similar, whereas stratified lakes differed from unstratified lakes and each other. Metabolic rates were higher in stratified lakes, and the lake with the shallowest chemocline (nutrients closest to the surface) possessed the highest rates of community respiration (CR) and gross primary production (GPP). We performed experimental additions to identify key factors for C cycling groups and their responses to changing C and N; we found that incubations changed communities in a similar manner across lakes (e.g. Pseudoalteromonas increased), but communities remained clustered according to stratification. Net autotrophy was correlated with increased levels of Synechococcus, and N addition often increased Synechococcus. N and C co-additions caused the greatest community shifts and also drove metabolic shifts from autotrophy to heterotrophy. While addition of C alone never increased CR to the same degree, C additions resulted in communities that clustered with communities from N and C co-additions. Network analysis identified changes in community structure associated with high CR and GPP (usually stimulated by N and C co-addition). Collectively these results suggest that changes in C-cycling rates are accompanied by underlying shifts in microbial interactions, including rapid responses in key taxa, as well as overall modification of microbial network structure.

When: Oct. 19th, Thursday, 12pm – 1pm
Where: SE2-302

Coffee will be provided and please bring your own mugs.
We look forward to seeing you,

Organizers for 2017-18: Nate Bogie and Lixia Jin
Faculty coordinator: Asmeret Asefaw Berhe

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ucmerced.edu/pipermail/enviro-lunch/attachments/20171017/797d9e2f/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: PastedGraphic-1.png
Type: image/png
Size: 25776 bytes
Desc: PastedGraphic-1.png
URL: <http://lists.ucmerced.edu/pipermail/enviro-lunch/attachments/20171017/797d9e2f/attachment-0001.png>