Xiahong Feng Stable Isotope Geochemistry and Hydrochemistry

Contact Information:

Overview of Research:

The main feature of my research is the interdisciplinary approach to global and local environmental problems. I use major and trace element concentrations and variations of stable isotopic ratios of oxygen, hydrogen, carbon and nitrogen in natural materials, such as rocks, water, tree-rings, soils and air, to study the function and dynamics of natural systems, to trace the history of the climatic and environmental changes and to understand the mechanisms for such changes. Recent projects include solute and contaminant transport in watersheds or in snow and their effects on stream chemistry, rates and mechanisms of plant and soil organic matter decomposition and the implications to the global carbon cycle, and reconstruction of paleohumidity using oxygen and hydrogen isotopic compositions of tree rings. These research topics are discussed in more detail below:

• Effect of Sea Ice on Arctic Precipitation
• Hydrogen and oxygen isotope studies of tree rings
• Oxygen and hydrogen isotopic compositions in leaf water
• Study of plants’ water used efficiency using C isotopes of tree rings
• Carbon and nitrogen cycles in plant-soil systems
• Isotope hydrology and hydrochemistry

Research Group Website: Stable Isotopes Laboratory

Selected Recent Publications:

1. Feng, X. , A. M. Faiia, and E. S. Posmentier (2009), Seasonality of isotopes in precipitation: A global perspective, J. Geophys. Res. , 114, D08116, doi:10.1029/2008JD011279

2. Lee, J., Feng, X. , Posmentier, E.S., Faiia A.M. and Taylor S. (2009) Stable isotopic exchange rate constant between snow and liquid water. Chemical Geology , 260, 57-62.

3. Lee, J., Nez, V., Feng, X. , Kirchner, J.W., Osterhuber, R., Renshaw, C.E. (2008) A study of solute redistribution and transport in seasonal snowpack using natural and artificial tracers. Journal of Hydrology , 357 (3-4), 243-254.

4. Wang, G., Feng, X. , Han, J., Zhou, L., Tan, W. and Su, F. (2008) Paleovegetation reconstruction using d 13 C of soil organic matter. Biogeosciences , 5, 1325-1337 .

5. Shu, Y., Feng, X. , Posmentier, E.S., Faiia, A.M., Ayres, M.P., Conkey L.E. and Sonder L.J. (2008) Isotopic studies of leaf water 2. Between-age isotopic variations in pine needles. Geochimica et Cosmochimica Acta, 72, 5189-5200.

6. Shu, Y., Feng, X. Posmentier, E.S., Sonder L.J., Faiia, A.M. and Yakir, D. (2008) Isotopic studies of leaf water 1. A physically based two-dimensional model for pine needles. Geochimica et Cosmochimica Acta, 72, 5175-5188.

7. Lee, J., Feng, X. , Posmentier, E.S., Faiia, A.M., Osterhuber, R., Kirchner J.W. (2008) Modeling of solute transport in snow using conservative tracers and artificial rain-on-snow experiments, Water Resources Research , 44, W02411, doi:10.1029/2006WR005477.

8. Feng, X. , Reddington, A.L., Faiia, A.M., Posmentier, E.S., Shu Y., and Xu, X. (2007) Changes in North American atmospheric circulation patterns indicated by wood cellulose, Geology , 35(2), 163-166, doi: 10.1130/G22884A.1.

9. Lennon *, J.T. Faiia, A.M. Feng, X., Cottingham, K.L. (2006) Evidence for CO 2 recycling in lakes along a terrestrial carbon gradient, Limnology and Oceanography, 51(4), 1602-1613.

10. Liu, W., Feng, X., Ning, Y., Zhang, Q., Cao, Y., and An, Z. (2005) d 13C variation of C 3 and C 4 plants across an Asian monsoon rainfall gradient in arid northwestern China, Global Change Biology, 11, 1094-1100.
11. Shu *, Y., Feng, X., Gazis, C., Anderson, D. Faiia *, A.M., Tang *, K., Ettl, G.J. (2005) Relative humidity recorded in tree rings: a study along a precipitation gradient in the Olympic Mountains, Geochimica et Comochimica Acta, 69, 791-799.

Complete CV