Large Nitrogen Cycle Perturbations During the Early Triassic Hyperthermal Interval
Creator(s):
Du, Yong
Song, Huyue
Stüeken, Eva E
Grasby, Stephen
Song, Haijun
Tian, Li
Chu, Daoliang
Dal Corso, Jacopo
Li, Zhe
Tong, Jinnan
Abstract:
Ocean temperature, redox state, circulation, and nutrient levels regulate marine nitrogen (N) cycle, yet their impacts during greenhouse intervals remain poorly understood. Here, we examined the Smithian–Spathian hyperthermal event (~250.5 Ma) during the Early Triassic greenhouse using stable N isotopes (δ15NDCN) from two basins in South China. The Smithian hyperthermal interval exhibited low δ15NDCN (+1‰ – +3‰), indicating N deficiency and enhanced N2 fixation. Subsequent cooling across the Smithian–Spathian boundary led to discrete δ15NDCN changes, likely reflecting signals of partial NH4+ assimilation in anoxic and NH4+-enriched conditions. In the early Spathian with milder temperatures, biological N gradually changed to nitrate-dominated sources from partial denitrification, as indicated by increased δ15NDCN (up to +3‰ – +6‰). Eukaryotic algae thrived while prokaryotes declined during the Spathian, evidenced by elevated δ15NDCN and Δ13Ccarb-org (carbonate-organic carbon isotope difference). These findings highlight significant turnovers in N cycle in response to temperature changes in low-latitude South China.
How to cite this dataset:
Du, Y., Song, H., Stüeken, E. E., Grasby, S., Song, H., Tian, L., Chu, D., Dal Corso, J., Li, Z., Tong, J., 2023. Large Nitrogen Cycle Perturbations During the Early Triassic Hyperthermal Interval, Version 1.0. Interdisciplinary Earth Data Alliance (IEDA).
https://doi.org/10.26022/IEDA/112952. Accessed 2024-05-15.
DOI Creation Date:
2023-06-22
Related
Publication(s):
Du, Y., Song, H., Grasby, S.E. et al., (2023). Recovery from persistent nutrient-N limitation following the Permian–Triassic mass extinction. Earth and Planetary Science Letters, 602: 117944;
Du, Y., Song, H., Tong, J. et al., (2021). Changes in productivity associated with algal-microbial shifts during the Early Triassic recovery of marine ecosystems. Geological Society of America Bulletin, 133(1-2), 362-378
License:
Creative Commons Attribution-ShareAlike 4.0 International [CC-BY-SA-4.0]
Keyword(s):
Coverage Scope: Regional (Continents, Oceans)
Geographic Location: South China, Tethys
User Contributed Keyword(s):
nitrogen isotopes, Early Triassic, greenhouse, denitrification
Data Available On:
2023-06-23