New paper out in #JGR #Biogeosciences written by the excellent Yeganeh Mirzei. I was very happy to collaborate with her on the application of #machineLearning methods and validation to the dataset of #StLawrence sedimentary organic matter, #sedimentaryOM.
Please contact me directly for a copy following sharing guidelines for Wiley journal articles.
http://doi.org/10.1029/2025JG009527
RE: https://mastodon.social/@EuroGeosciences/115666291558411415
Featuring my co-authored #review #article « #Reviews and #syntheses: Best practices for the application of #marine #GDGTs as proxy for #paleotemperatures: #sampling, #processing, #analyses, #interpretation, and #archiving protocols » published in the @EuroGeosciences journal #Biogeosciences one month ago!
https://doi.org/10.5194/bg-22-6465-2025
#Science
#ScienceMastodon
#AcademicMastodon
#Consensus #Synthesis
#isoGDGTs #brGDGTs #TeamArchaea #TeamBacteria
#archaeal #bacterial #tetraether #lipids
RE: https://mastodon.world/@nina_davtian/114502798389880294
Let's give a try to the new #QuotePost functionality, so that I can remind the names of the lead authors of my new co-authored #review paper published in the @EuroGeosciences #journal #Biogeosciences, as well as which team and research center I represent in this #synthesis!
https://doi.org/10.5194/bg-22-6465-2025
#Science
#ScienceMastodon
#AcademicMastodon
#Consensus #Scientific #Publication
#isoGDGTs #brGDGTs #TeamArchaea #TeamBacteria
#archaeal #bacterial #tetraether #lipids
#Paleotemperature #Biogeoscience
Abstract. Membrane lipids of ammonia-oxidizing Thaumarchaeota, in particular isoprenoidal glycerol dialkyl glycerol tetraethers (isoGDGTs) and hydroxylated isoGDGTs (OH-isoGDGTs), have been used as biomarkers and as proxies in various environments. Controlled growth experiments have been used to investigate the factors that influence the composition of these lipids, in particular on how these factors affect the TEX86 temperature proxy, which is based on the degree of cyclization of isoGDGTs. Recently, the ring index of OH-isoGDGTs (RI-OH′), based on cyclization patterns of OH-isoGDGTs, and the abundance of OH-isoGDGTs relative to summed abundances of OH-isoGDGTs and regular isoGDGTs (% OH) have emerged as promising temperature proxies. Here, we examined the impact of growth temperature and growth phase on the distribution of OH-isoGDGTs and their associated proxies using cultures of two thaumarchaeotal strains. Analysis of core lipids and headgroup compositions of isoGDGTs and OH-isoGDGTs showed no consistent differences between the mid-exponential and stationary phases for both strains. Nitrosopumilus adriaticus NF5 shows a substantially higher relative abundance of OH-isoGDGTs (∼ 49 %) compared to Nitrosopumilus piranensis D3C (∼ 5 %) and also relative to observations reported for core lipids in the marine environment (< 17 %), indicating large variations in % OH values even among closely related species. Unlike in the marine environment, the % OH did not decrease with increasing temperatures in either of the strains, possibly reflecting a threshold below 15 °C for this response in the natural environment. The RI-OH′ increases with increasing temperature in cultures of both strains, similar to the ring index of regular isoGDGTs. The relative abundances of the headgroups varied between strains and did not respond to changes in temperature or growth phase. The % OH and RI-OH′ calculated from intact polar lipids with different headgroups revealed large differences between the distinct intact polar lipids, similar to that previously observed for regular isoGDGTs. Together, our findings suggest that growth temperature has a pronounced effect on the degree of cyclization in isoGDGTs and OH-isoGDGTs, in contrast to the relative abundance of OH-isoGDGTs, which mainly exhibits interspecies variability.
Following the 20th anniversary of its journal #Biogeosciences, the @EuroGeosciences provided some statistics. What a journey it has been!
- 1st submission received: 11 March 2004
- 1st final revised article published: 13 August 2004
- Preprints posted: 6,589
- Final articles published: 5,697
- Editors (incl. guest editors): 409
- Reviewer comments posted in the public discussion: 14,778
- Comments posted in the public discussion: 31,001
- Final article pages published: 92,115
Outtakes from #midjourney generated illustrations for #AGU22 presentation sessions. Prompts are quotes from session abstracts presented by members of the #BigData Cluster.
(prompts L-R)
1 - soil gas and water chemistry data
2 - a noticeable deterioration of water quality
3 - unprecedented wildfires and reduced snowmelt runoff
4 - using AI techniques with a focus on detecting peak anomalies
#EarthScience #CriticalZone #biogeosciences #Science #SciComm
As snow falls and daylight dims, the final sessions of #AGU22 begin. We're settling in for a few hours of Catchment and Critical Zone Science – Understanding Ecosystems Through Monitoring, Analysis, and Experimentation.
🔗 🗓️ : https://bit.ly/3hDEYch
Convened by Big Data Cluster collaborator Jamie Shanley and features a wide range of #CriticalZone research questions looking at #watershed #catchments
Catchment, critical zone, and ecosystem studies are foundational to hydrological and biogeochemical process understanding. These place-based studies with sustained monitoring have shaped our understanding of fundamental processes and consequences of environmental change on ecosystems. They also inform environmental policy and lead to transformative ideas that advance science and benefit society. In this session we seek contributions that synthesize hydrologic and biogeochemical findings and concepts, including across sites and over time. We encourage contributions from catchment, critical zone, and observatory studies, particularly research programs that are crucial to scientific discovery, resource management, shaping policy, or promoting societal well-being.
Gregor Kos
Nina Davtian
Jean-Pierre Gattuso 🇪🇺🇺🇦🍉
The Big Data Cluster