绿帽换妻

I am particularly interested in minimizing the negative impact of managed lands on climate, water, and air quality. My expertise is in greenhouse gas and reactive trace gas emissions from diverse ecosystems including restored wetlands and agricultural land. I employ field monitoring and manipulation techniques in addition to process-based biogeochemical modeling with an emphasis on model-data fusion approaches. I collaborate with regional to global-scale modeling projects and am actively incorporating models into carbon policies in California.

• PhD Department of Biology, University of Virginia
• B.S. Department of Ecology and Evolution, UC Santa Barbara

1. Delwiche, K.,…Oikawa, P.Y.,…Baldocchi, D.D. (2025) Dynamic methane emissions in a restored wetland: Decadal insights into uncertain climate outcomes and critical science needs. Agricultural and Forest Meteorology

2. Reed, D.E. Chu, H….Oikawa, P.Y….Zona, D. (2025) Network of networks: Time series clustering of Ameriflux sites. Agricultural and Forest Meteorology.
3. Oikawa P.Y., D. Sihi, I. Forbrich, E. Fluet-Chouinard, M. Najarro, *O. Thomas, *J. Shahan , A. Arias-Ortiz, S. Russell, S.H. Knox, G. McNicol, J. Wolfe, L. Windham-Myers, E. Stuart-Haentjens, S.D. Bridgham, B. Needelman, R. Vargas, K. Schäfer, E.J. Ward, P. Megonigal, and J. Holmquist (2024) A New Coupled Biogeochemical Modeling Approach Provides Accurate Predictions of Methane and Carbon Dioxide Fluxes Across Diverse Tidal Wetlands. Journal of Geophysical Research: Biogeosciences, 129(10), p.e2023JG007943.
4. Koontz, E.L., S.M. Parker, A.E. Stearns, B.J. Roberts, C.M. Young, L. Windham-Myers, Y. Oikawa,…J.R. Holmquist (2024) Controls on spatial variation in porewater methane concentrations across United States tidal wetlands. Science of the Total Environment. Accepted.
5. Arias‐Ortiz, A., Wolfe, J., Bridgham, S.D., Knox, S., McNicol, G., Needelman, B.A., *Shahan, J., Stuart‐Haëntjens, E.J., Windham‐Myers, L., Oikawa, P.Y., Baldocchi, D.D….Holmquist J.R. (2024) Methane fluxes in tidal marshes of the conterminous United States. Global Change Biology, 30(9), p.e17462.
6. Richardson, J.L., Desai, A.R., Thom, J…Oikawa P.Y., *J. Shahan, M. Matsumura (2024) On the Relationship Between Aquatic CO₂Concentration and Ecosystem Fluxes in Some of the World’s Key Wetland Types. Wetlands 44, 1.
7. *Fenster, T.L., Torres, I., Zeilinger, A., Chu, H. and Oikawa, P. (2023) Compost amendment to a grazed California annual grassland increases gross primary productivity due to a longer growing season. Journal of Geophysical Research: Biogeosciences, 128(12), p.e2023JG007621.
8. Bansal, S., Creed, I.F., Tangen, B.A., … Oikawa, P., …. and Zhu, X. (2023) Practical guide to measuring wetland carbon pools and fluxes. Wetlands (Mark Brinson Review) 43:105 
9. Windham–Myers, L., Oikawa, P., Deverel, S., Chapple, D., Drexler, J.Z. and Stern, D., (2023) Carbon Sequestration and Subsidence Reversal in the Sacramento–San Joaquin Delta and Suisun Bay: Management Opportunities for Climate Mitigation and Adaptation. San Francisco Estuary and Watershed Science, 20(4).
10. Russell, S.J., Windham-Myers, L., Stuart-Haëntjens, E.J., Bergamaschi, B.A., Anderson, F., Oikawa, P. and Knox, S.H. (2023) Increased salinity decreases annual gross primary productivity at a Northern California brackish tidal marsh. Environmental Research Letters, 18(3), p.034045.
11. *Shahan, J., Chu, H., Windham‐Myers, L., Matsumura, M., Carlin, J., Eichelmann, E., Stuart‐Haentjens, E., Bergamaschi, B., Nakatsuka, K., Sturtevant, C. and Oikawa, P.Y. (2022) Combining eddy covariance and chamber methods to better constrain CO₂ and CH₄ fluxes across a heterogeneous restored tidal wetland. Journal of Geophysical Research: Biogeosciences, 127(9), p.e2022JG007112.
12. Andrews, H.M., Homyak, P.M., Oikawa, P.Y., Wang, J. and Jenerette, G.D. (2022) Water-conscious management strategies reduce per-yield irrigation and soil emissions of CO2, N2O, and NO in high-temperature forage cropping systems. Agriculture, Ecosystems & Environment, 332, p.107944.
13. Arias‐Ortiz, A., Oikawa, P.Y., Carlin, J., Masqué, P., *Shahan, J., Kanneg, S., Paytan, A. and Baldocchi, D.D. (2021) Tidal and nontidal marsh restoration: A trade‐off between carbon sequestration, methane emissions, and soil accretion. Journal of Geophysical Research: Biogeosciences, 126(12), p.e2021JG006573.
14. Miller, G.J., Dronova, I., Oikawa, P.Y., Knox, S.H., Windham-Myers, L., *Shahan, J. and Stuart-Haëntjens, E. (2021) The potential of satellite remote sensing time series to uncover wetland phenology under unique challenges of tidal setting. Remote Sensing, 13(18), p.3589.
15. Eichelmann, E., Mantoani, M.C., Chamberlain, S.D., Hemes, K.S., Oikawa, P.Y., Szutu, D., Valach, A., Verfaillie, J. and Baldocchi, D.D. (2022) A novel approach to partitioning evapotranspiration into evaporation and transpiration in flooded ecosystems. Global change biology, 28(3), pp.990-1007.
16. Novick, K.A., S. Metzger, WRL Anderegg, M. Barnes, D.S. Cala, K. Guan, K.S. Hemes, D.Y. Hollinger, J. Kumar, M. Litvak, D. Lombardozzi, C.P. Normile, Y. Oikawa, B.R.K. Runkle, M. Torn, S. Wiesner (2022) Informing Nature‐based Climate Solutions for the United States with the best‐available science. Global change biology, 28(12), pp.3778-3794.
17. Fenster, T.L., Oikawa, P.Y. and Lundgren, J.G. (2021) Regenerative almond production systems improve soil health, biodiversity, and profit. Frontiers in Sustainable Food Systems, 5, p.664359.
18. Irvin, J., Zhou, S., McNicol, G., Lu, F., Liu, V., Fluet-Chouinard, E., Ouyang, Z., Knox... Oikawa, P.Y….Jackson, R.B. (2021) Gap-filling eddy covariance methane fluxes: Comparison of machine learning model predictions and uncertainties at FLUXNET-CH4 wetlands. Agricultural and Forest Meteorology, 308, p.108528.
19. Wang, Y., C. Ge, L. Castro Garcia, D. Jenerette, Oikawa, J. Wang (2021) Improved modeling of soil NOx emissions in a high temperature agricultural region: role of background emissions on NO₂ trend over the US. Environmental Research Letters, 16(8), p.084061.
20. Chu, H., X. Luo, Z. Ouyang,… Y. Oikawa, … D. Zona (2021) Representativeness of Eddy-Covariance Flux Footprints for Areas Surrounding Ameriflux Sites. Agricultural and Forest Meteorology 301 p.108350.
21. Delwiche, K.B., Knox S.H.,…Y. Oikawa…R.B. Jackson (2021) FLUXNET-CH4: A global, multi-ecosystem dataset and analysis of methane seasonality from freshwater wetlands Earth System Science Data Discussions(2021): 1-111.
22. Dronova, I., S. Taddeo, K. Hemes, S.H. Knox, A. Valach, Y. Oikawa, K. Kasak, D.D. Baldocchi (2021) Remotely sensed phenological heterogeneity of restored wetlands: linking vegetation structure and function. Agricultural and Forest Meteorology 296 (2021): 108215
23. Fertitta-Roberts, C., Oikawa, P.Y., Jenerette G.D. (2019) Evaluating the GHG mitigation-potential of alternate wetting and drying in rice through life cycle assessment. Science of the Total Environment. 653:1343-1353.
24. Hemes, K., Eichelmann, E., Chamberlain S.D., Knox S.H., Oikawa, P.Y., Sturtevant C., Verfaillie J., Baldocchi D.D. (2018) A unique combination of aerodynamic and surface properties contribute to surface cooling in restored wetlands of the Sacramento-San Joaquin Delta, California. Journal of Geophysical Research Biogeosciences, DOI: 10.1029/2018JG004494
25. Chamberlain, S.D., T. Anthony, W. Silver, Eichelmann, E., K. Hemes, Y. Oikawa, C. Sturtevant, D. Szutu, J. Verfaillie, D.D. Baldocchi (2018) Soil properties and sediment accretion modulate methane fluxes from restored wetlands. Global Change Biology, DOI: 10.1111/gcb.14124
26. Eichelmann, E., K. Hemes, S.H. Knox, Y. Oikawa, S.D. Chamberlain, C. Sturtevant, J. Verfaillie, D.D. Baldocchi (2018) The effect of land cover type and structure on evapotranspiration from agricultural and wetland sites in the Sacramento–San Joaquin River Delta, California. Agricultural and Forest Meteorology, 256:179-195.
27. Oikawa, P.Y., G.D. Jenerette, S.H. Knox, C. Sturtevant, J. Verfaillie, I. Dronova, C.M. Poindexter, Eichelmann, E., D.D. Baldocchi (2017) Evaluation of a hierarchy of models reveals importance of substrate limitation for predicting carbon dioxide and methane exchange in restored wetlands. Journal of Geophysical Research, Biogeosciences, doi:1002/2016JG003438.
28. Oikawa, P.Y., Sturtevant, S.H. Knox, J. Verfaillie, Y.W. Huang, D.D. Baldocchi. (2017) Revisiting the partitioning of net ecosystem exchange of CO₂ into photosynthesis and respiration with simultaneous flux measurement of ¹³CO₂ and CO₂, soil respiration and a biophysical model, CANVEG. Agricultural and Forest Meteorology, 234:149-163.
29. Jardine K.J., Fernandes de Souza V., Oikawa, P.Y., Higuchi N., Bill M., Porras R., Niinemets U., Chambers J. (2017) Integration of C1 and C2 metabolism in trees. International J. of Molecular Sciences, doi:3390/ijms18102045.
30. Knox, S.H., I. Dronova, C. Sturtevant, Oikawa, P.Y., Matthes, J., J. Verfaillie, D.D. Baldocchi (2017) Using digital camera and Landsat imagery with eddy covariance data to model gross primary production in restored wetlands. Agricultural and Forest Meteorology 237: 233-245.
31. Baldocchi, D.D., S.H. Knox, I. Dronova, Verfaillie, P.Y. Oikawa, C. Sturtevant, J. Hatala-Mathes, M. Detto (2016) The impact of expanding flooded land area on the annual evaporation of rice. Agricultural and Forest Meteorology, 223:181-193.
32. Knox, S.H., J. Hatala-Mathes, C. Sturtevant, Y. Oikawa, J. Verfaillie, D.D. Baldocchi (2016) Biophysical controls on the interannual variability in ecosystem-scale in CO₂ and CH₄ exchange in a California rice paddy. Journal of Geophysical Research: Biogeosciences, doi: 10.1002/2015JG003247.
33. Oikawa, P.Y., C. Ge, J. Wang, J.E. Eberwein, L. Liang, L.A. Allsman, D.A. Grantz, G.D. Jenerette (2015) Unusually high soil nitrogen oxide emissions influence air quality in high temperature agricultural region. Nature Communications, https://doi.org/10.1038/ncomms9753.
34. Sturtevant, C., B.L. Ruddell, S.H. Knox, J. Verfaillie, J. Hatala, Y. Oikawa, D.D. Baldocchi (2015) Identifying scale-emergent, nonlinear, asynchronous processes of wetland methane exchange. Journal of Geophysical Research: Biogeosciences, 121(1), pp.188-204.
35. Eberwein, J.R., Oikawa, P.Y., Allsman, L.A. and Jenerette, G.D. (2015) Carbon availability regulates soil respiration response to nitrogen and temperature. Soil Biology and Biochemistry, 88, pp.158-164.
36. Eberwein, J.E., Y. Oikawa, L.A. Allsman, G.D. Jenerette (2014) The effects of C, N and temperature interactions on soil respiration quantified through Michaelis-Menten kinetics. Journal of Soil Biology and Biochemistry.
37. Oikawa, P.Y., G.D. Jenerette, A. Grantz (2014) Offsetting high water demands with high productivity: Sorghum as a biofuel crop in a high irradiance arid ecosystem. Global Change Biology Bioenergy, doi:10.1111/gcbb.12190.
38. Oikawa, P.Y., D.A. Grantz, A. Chatterjee, J.E. Eberwein, L.A. Allsman, G.D. Jenerette (2014) Unifying soil respiration pulses, inhibition, and temperature hysteresis through dynamics of labile carbon and soil O₂. Journal of Geophysical Research: Biogeosciences,
39. Oikawa, P.Y., M.T. Lerdau (2013) Catabolism of phytogenic volatile organic compounds. Trends in Plant Science, 18:695-703.
40. Oikawa, P.Y., B.M. Giebel, L. da S.L. Sternberg, L. Li, M.P. Timko, P.K. Swart, D.D. Riemer, J.E. Mak, M.T. Lerdau (2011) Leaf and root pectin methylesterase activity and ¹³C/¹²C stable isotopic ratio measurements of methanol emissions give insight into methanol production in Lycopersicon esculentum. New Phytologist, 191:1031-1040.
41. Oikawa, P.Y., L. Li, M.P. Timko, J.E. Mak, M.T. Lerdau (2011) Short term changes in methanol emission and pectin methylesterase activity are not directly affected by light in Lycopersicon esculentum. Biogeosciences, 8:1023-1030

Oikawa, P.Y., C. Fertitia, S. Knox, E. Eichelman, C. Sturtevant, K. Hemes, J. Verfaillie, J. Hatala-Matthes, G.D. Jenerette, D.D. Baldocchi. 2017. Improving ecosystem model PEPRMT and remote sensing photosynthesis (GPP) products in wetlands using stable carbon and oxygen isotopes. Ecological Society of America. Portland, OR (oral presentation)

Oikawa, P.Y., C. Fertitia, S. Knox, E. Eichelman, C. Sturtevant, K. Hemes, J. Verfaillie, J. Hatala-Matthes, G.D. Jenerette, D.D. Baldocchi. 2017. Modeling effects of Alternate Wetting and Drying (AWD) on methane fluxes from rice. FLUXNET conference. Berkeley, CA (poster presentation)

Deverel, S., Dore S., Oikawa P.Y., Knox S., Brock B. 2016. Greenhouse gas emissions reductions on agricultural lands in the Sacramento-San Joaquin Delta using the protocol for wetland implementation and rice cultivation. Bay-Delta Science Conference, Oakland, CA (poster presentation)

Oikawa, P.Y. 2016. Modeling greenhouse gases in restored wetlands in the Sacramento-San Joaquin River Delta, Affinity Speaker Series and Earth and Environmental Sciences Seminar Series, 绿帽换妻, East Bay

Deverel, S., P.Y. Oikawa. 2016. Methodology for quantifying greenhouse gas emissions reductions: Wetland implementation and rice cultivation in the Sacramento-San Joaquin Delta, San Francisco Estuary and the California Coast, American Carbon Registry Webinar (webinar)

Oikawa, P.Y., S. Knox, C. Sturtevant, J. Verfaillie, I. Dronova, C. Poindexter, G.D. Jenerette, D.D. Baldocchi. 2015. Using eddy covariance of CO₂, ¹³CO₂ and CH₄, continuous soil respiration measurements, and digital photography to constrain a process-based biogeochemical model for carbon market-funded wetland restoration. American Geophysical Union. San Francisco, CA (oral presentation)

Oikawa, P.Y., G.D. Jenerette, S. Knox, C. Sturtevant, J. Verfaillie, I. Dronova, C. Poindexter, D.D. Baldocchi. 2015. Farming carbon instead of corn: A biogeochemical model for carbon market-funded wetland restoration. Ecological Society of America. Baltimore, Maryland. (oral presentation)

Oikawa, P.Y., G.D. Jenerette, S. Knox, C. Sturtevant, J. Verfaillie, I. Dronova, C. Poindexter, D.D. Baldocchi. 2015. Farming carbon instead of corn: A biogeochemical model for carbon market-funded wetland restoration. USDA-NIFA Postdoctoral Fellows Meeting. Washington, D.C. (poster presentation)

Oikawa, P.Y., S. Knox, J. Verfaillie, C. Sturtevant, G.D. Jenerette, B. Brock, J.D. Jenerette, D.D. Baldocchi. 2015. Farming carbon instead of corn: A biogeochemical model for carbon market funded wetland restoration. Department of Environmental Science, Policy and Management, UC Berkeley. (oral presentation)

Oikawa, P.Y., G.D. Jenerette, S. Knox, C. Sturtevant, J. Verfaillie, I. Dronova, C. Poindexter, D.D. Baldocchi. 2015. Process-based modeling of CO₂ and CH₄ from managed peatland systems: introducing the PEPRMT model. Society for Wetland Scientists. Providence, Rhode Island. (oral presentation)

Oikawa, P.Y., S. Knox, J. Verfaillie, C. Sturtevant, G.D. Jenerette, B. Brock, D.D. Baldocchi. 2014. Process-based modeling of CO₂ and CH₄ from managed peatland systems. Data Assimilation in Biogeochemical Cycles. Trieste, Italy. (poster presentation)

Oikawa, P.Y., S. Knox, J. Verfaillie, C. Sturtevant, G.D. Jenerette, B. Brock, D.D. Baldocchi. 2014. Improving process-based modeling of CO₂ and CH₄ from managed peatland systems. Air Pollution and Global Change Symposium. Monterey, CA. (poster presentation)

Oikawa, P.Y., G.D. Jenerette, S. Knox, C. Sturtevant, J. Verfaillie, D.D. Baldocchi. 2014. Improving process-based modeling of CO₂ and CH₄ from managed wetland and rice systems in the Delta. Bay-Delta Science Conference. Oakland, CA. (poster presentation)

Oikawa, P.Y., D.A. Grantz, A. Chatterjee, J.R. Eberwein, L.A. Allsman, G.D. Jenerette. 2012. Factors regulating soil surface CO₂ and NO_x flux in response to high temperature, pulse water events, and nutrient fertilization. American Geophysical Union. San Francisco, CA. (oral presentation)

Oikawa, P.Y., D.A. Grantz, G.D. Jenerette. 2011. Variation in the temperature sensitivity of heterotrophic soil respiration in response to pulse water events and substrate limitation. American Geophysical Union. San Francisco, CA. (poster presentation)

Oikawa, P.Y., D.A. Grantz, G.D. Jenerette. 2011. Investigating heterotrophic soil respiration in response to pulse water events. Department of Botany and Plant Sciences Seminar, University of California Riverside, CA. (invited oral presentation)

Oikawa, P.Y., L. Li, M.P. Timko, J.E. Mak, M.T. Lerdau. 2010. Short term changes in methanol emission and pectin methylesterase activity are not directly affected by light in Lycopersicon esculentum. American Geophysical Union. San Francisco, CA. (poster presentation)

Oikawa, P.Y., B.M. Giebel, L. da S.L. Sternberg, L. Li, M.P. Timko, P.K. Swart, D.D. Riemer, J.E. Mak, M.T. Lerdau. 2010. Investigating the source of mature leaf methanol emissions in tomato Lycopersicon esculentum. Gordon Research Conference on Biogenic Hydrocarbons and the Atmosphere. Les Diablerets, Switzerland. (invited oral presentation)