Office of Research, UC Riverside
Emma Aronson
Assistant Professor
Microbiology & Plant Pathology
emmaa@ucr.edu
(951) 827-4201


RAPID: Gauging the impacts of California's 500-year drought on aeolian inputs to mountain soils and ecosystems

AWARD NUMBER
006933-002
FUND NUMBER
21279
STATUS
Closed
AWARD TYPE
3-Grant
AWARD EXECUTION DATE
7/14/2014
BEGIN DATE
8/1/2014
END DATE
7/31/2015
AWARD AMOUNT
$29,985

Sponsor Information

SPONSOR AWARD NUMBER
EAR-1449197
SPONSOR
NATIONAL SCIENCE FOUNDATION
SPONSOR TYPE
Federal
FUNCTION
Organized Research
PROGRAM NAME

Proposal Information

PROPOSAL NUMBER
14121141
PROPOSAL TYPE
New
ACTIVITY TYPE
Basic Research

PI Information

PI
Aronson, Emma
PI TITLE
Other
PI DEPTARTMENT
Microbiology & Plant Pathology
PI COLLEGE/SCHOOL
College of Nat & Agr Sciences
CO PIs

Project Information

ABSTRACT

Mounting evidence shows that California is currently experiencing the most severe drought since 1580, yet it is likely that droughts such as these will become more common as the climate changes. Any drought, particularly one of this magnitude, can elevate dust transport, from fallow croplands and bare natural ecosystems, to sometimes distant locations. The dust being transported may bring nutrients and microorganisms, with unknown, but potentially transformational, impacts on the ecosystems where the dust is deposited. This project proposes to take advantage of the unique extremity of the current drought by measuring the ecosystem impact of increased dust to the Sierra Nevada mountains. The investigator will measure the amount and microbial composition of dust transported to the Sierras. Collaborators will determine the origin (using isotopic chemistry) and chemical makeup of the dust. In the future, the investigator will endeavor to compare the data rapidly collected during this year of extreme drought to data to be collected in wetter years.

Dust will be collected at four sites along an elevational gradient in the Southern Sierra Critical Zone Observatory (SSCZO), ranging from 400 m to 2700 m elevation. At each site, dust will be collected monthly through November 2014, and again in Spring 2015, from passive dust collectors and from filters (1 um pore size) on the Eddy Covariance Towers active CO2 samplers. To complement dust collection, soil samples (10 cm depth) will be collected within the footprint of the towers. The origin of dust samples will be determined using radiogenic strontium (Sr) and neodymium (Nd) isotopic tracers. Nutrients and microbial composition of dust and soil samples will also be analyzed. This approach will allow to identify the effects of mega-droughts on i) dust-related contributions to the geobiology and biogeochemistry of soils and ecosystems, ii) the role of local versus distant dust sources of microorganisms, including bacteria, archaea and fungi, and of nutrients to the Sierra Nevada, and iii) the role of elevation in determining the ecological effects of mega-drought-induced dust transport.
(Abstract from NSF)