I obtained my PhD from IISc Bangalore where I worked on developing a new proxy for atmospheric relative humidity levels. This work led to the establishment of stable isotope ratios of carbon and oxygen in rice (Oryza sativa L.) grains as a proxy for relative humidity levels. The calibration curve thus obtained was applied to archaeological rice grains for reconstructing palaeo-relative humidity at the sites of Harappan civilization. Recently, I developed the first empirical relationship between the triple oxygen isotope composition of rice grain phytoliths (biogenic silica) and relative humidity. This state-of-the-art approach enables the reconstruction of paleo-relative humidity using well-preserved phytoliths.
For my postdoctoral research, I received the Academia Sinica Fellowship (2019) and the Sir Charles Clore Postdoctoral Fellowship (2022) for conducting postdoctoral research in Taiwan and Israel, respectively. These research projects were undertaken in Dr. Danie Liang’s laboratory in Academia Sinica and Prof. Dan Yakir’s Biosphere -Atmosphere Research Group at the Weizmann Institute of Science, Israel. My postdoctoral research at these two institutions included the application of triple oxygen isotopes in nitrate to investigate nitrate dynamics in freshwater reservoirs, and the development of hyperspectral remote sensing technique of sun induced chlorophyll fluorescence (SIF) as a proxy for gross primary productivity.
1. Ritika Kaushal, Prosenjit
Ghosh, and Ilya N. Bindeman. 2025. Triple oxygen isotopes of rice (Oryza
sativa L.) phytoliths as a quantitative proxy for relative humidity. Chemical
Geology, 122823. https://doi.org/10.1016/j.chemgeo.2025.122823
2. Ritika Kaushal, Yu-Hsin Hsueh,
Chi-Ling Chen, Yi-Ping Lan, Ping-Yu Wu, Yi-Chun Chen, Mao-Chang Liang. 2022.
Isotopic assessment of soil N2O emission from paddy soil under
varying N-inputs. Science of the Total Environment, 827, 154311. https://doi.org/10.1016/j.scitotenv.2022.154311.
3. Ritika Kaushal, Chao-Chen Lai,
Fuh-Kwo Shiah, and Mao-Chang Liang. 2021. Utilization of Δ17O for
nitrate dynamics in a subtropical freshwater reservoir. Science of The Total
Environment 753, 141836. https://doi.org/10.1016/j.scitotenv.2020.141836.
4. Ritika Kaushal, Prosenjit Ghosh
and Anil K. Pokharia. 2019. Stable isotopic signature in rice grains marking a
rapid hydroclimatic shift during the structural transformation of Harappan civilization.
Quaternary International, 512, 144-154. https://doi.org/10.1016/j.quaint.2019.04.017.
Impact factor: 2.2.
5. Ritika Kaushal and Prosenjit
Ghosh. 2018. Stable oxygen and carbon isotopic composition of rice (Oryza
sativa L.) grains as recorder of relative humidity." Journal of
Geophysical Research: Biogeosciences 123, 2, 423-439. https://doi.org/10.1002/2017JG004245.
6. Ritika Kaushal, Prosenjit Ghosh.
2018. Oxygen isotope enrichment in rice (Oryza sativa L.) grain organic
matter captures signature of relative humidity. Plant Science, 274, 503-513.
https://doi.org/10.1016/j.plantsci.2018.05.022.
7. Ritika Kaushal, Prosenjit
Ghosh., Heike Geilmann. 2016. Fingerprinting environmental conditions and
related stress using stable isotopic composition of rice (Oryza sativa L.) grain
organic matter. Ecological Indicators, 61, 941–951. https://doi.org/10.1016/j.ecolind.2015.10.050.
Institute Seed Grant (2025-2028). Biogeochemistry for Paleoclimate reconstruction and Seaweed Carbon Sequestration.
This funding is supporting stable isotope assessment of lagoonal and riverine molluscs in Odisha for paleoclimate reconstruction, and seaweed carbon research.
