HR: 1340h
AN: H13A-0962 [Abstracts]
TI: Southern Sierra Critical Zone Observatory: integrating water cycle and biogeochemical processes across the rain-snow transition
AU: * Bales, R
EM: rbales@ucmerced.edu
AF: University of California, Merced, Sierra Nevada Research Institute, Merced, CA 95344,
AU: Boyer, B
AF: University of California, Berkeley, Dept Env Science Policy & Mgmt, Berkeley, CA 94720-
3114,
AU: Conklin, M
AF: University of California, Merced, Sierra Nevada Research Institute, Merced, CA 95344,
AU: Goulden, M
AF: University of California, Irvine, Dept Earth System Science, Irvine, CA 92697-3100,
AU: Hopmans, J
AF: University of California, Davis, Hydrology Program, Hydrology Program, CA 95616,
AU: Hunsaker, C
AF: Pacific Southwest Research Station, USDA Forest Service, Fresno, CA 93710,
AU: Johnson, D
AF: University of Nevada, Reno, Natural Resources & Environmental Science, Reno, NV
89557,
AU: Kirchner, J
AF: University of California, Berkeley, Dept Earth & Planetary Science, Berkeley, CA 94720,
AU: Tague, C
AF: University of California, Santa Barbara, Bren School of Env Science, Santa Barbara, CA
93106-5131,
AB:
The Southern Sierra Critical Zone Observatory (CZO) is establishing a rain-snow transition research platform for
research by investigators from multiple disciplines and a research program aimed at yielding general knowledge
and tools for understanding the interactions between water, atmosphere, ecosystems and landforms in the
critical zone. A primary, overarching goal is to understand how critical zone processes control fluxes and stores of
water across the landscape, and how the water cycle modulates (bio)geochemical, biological, geomorphological
and soil processes in the critical zone. Five science questions define and focus the core measurement and
research program: i) how do coupled hydrologic and biogeochemical fluxes vary across the rain-snow transition,
ii) what is the role of extreme hydrologic events in water and biogeochemical balances, iii) to what extent does
vegetation modulate or actively control the primary subsurface fluxes of water and nutrients, iv) over what time and
space scales, and during what seasons, are short-circuit pathways dominant in the critical zone, and v) how
does the presence of a seasonal snowpack affect the subsurface, critical zone, soils, geomorphology,
biogeochemistry and hydrology, and how will the system respond as climate warms and snowpacks recede.
Some unique features of the Sierra Nevada system as compared to more mesic sites include: i) hydrophobic
soils, ii) islands of fertility in soils, iii) dominant role of catastrophic events, e.g. fire, and iv) spatial decoupling of
decomposition from root uptake in soil profile. The rationale for measurement design, including the value of
high-frequency data will be illustrated, as will the strategy for providing community data and information, and
educational programs.
UR: http://snri.ucmerced.edu/CZO
DE: 1804 Catchment
DE: 1863 Snow and ice (0736, 0738, 0776, 1827)
DE: 1876 Water budgets
SC: Hydrology [H]
MN: 2007 Fall Meeting