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Baseline concentrations of elements in the Antarctic macrolichen Umbilicaria decussata
Entry ID: Antar_Macrolichen_Umbilicaria


Summary
Abstract: Total concentrations of major and trace elements were determined in samples of
the epilithic lichen Umbilicaria decussata from 24 ice-free areas in coastal
Victoria Land (Antarctica) during 1991 - 2001. Overall average concentrations
of trace elements except Cd were the lowest ever reported for lichens of the
genus Umbilicaria. Specifically, the mean level of Pb in lichen from granitic
rock (0.46 +/- 0.18 mg/g-1 dry wt) was more than four times lower than the
lowest record in Arctic lichens. No impact of local human activities was
detected, but the elemental composition of U. decussata was affected by
entrapment of soil of rock dust particles and probably by uptake of soluble
elements from substrate.

Relationship between elements and their distributions patterns in the study
area indicated that the marine environment is the main source of major ions and
perhaps of Cd in lichens. Accumulation of P was detected in samples from
coastal sites frequented by seabirds. Although the present results can be taken
as baseline levels of major and trace elements in Antarctic U. decussata from
substrates with very different geochemical features, further research is
necessary to evaluate the relative element contribution from each substrate
with respect to those from snow, marine aerosol, salt encrustation and guano.

Geographic Coverage
 N: -72.0333 S: -77.0333  E: 162.4166  W: 170.1666
 Min Altitude: 3.0M  Max Altitude: 500.0M

Location Keywords
CONTINENT > ANTARCTICA > TERRA NOVA BAY
CONTINENT > ANTARCTICA > VICTORIA LAND
GEOGRAPHIC REGION > ARCTIC
GEOGRAPHIC REGION > POLAR


Science Keywords
LAND SURFACE >SOILS >MICRONUTRIENTS/TRACE ELEMENTS    [Definition]
BIOLOGICAL CLASSIFICATION >FUNGI >LICHENS    [Definition]
BIOSPHERE >ECOLOGICAL DYNAMICS >ECOSYSTEM FUNCTIONS >BIOGEOCHEMICAL CYCLES    [Definition]
BIOSPHERE >ECOLOGICAL DYNAMICS >ECOTOXICOLOGY >SPECIES BIOACCUMULATION    [Definition]


ISO Topic Category
BIOTA
GEOSCIENTIFIC INFORMATION


Platform
FIELD INVESTIGATION    [Information]


Instrument
SOIL SAMPLER    [Information]
SPECTROMETERS    [Information]


Quality
A composite sample of U. decussata thalli was collected from boulders and rock
outcrops in 24 hours. In each site, a sample of surface soil was collected. In
the laboratory of Baia Terra Nova station, the lichen and soil samples were
dried at 40 degrees C for 36 hrs. The lichens were then sorted to remove
extraneous materials and dead or senescent tissue. Soil samples were sorted to
remove gravel and larger organic debris and then sieved through a 0.20 mm
screen. Once in Italy samples were mineralized in clean Teflon vessels under
pressure with 2.5 ml conc. HNO3 at 120 degrees C for 8 hrs. A total of 13
elements were analyzed in the mineralized samples. Al, Fe, Na, K, Ca, Mg, Mn,
Cu, P and Zn concentrations were determined by air/acetylene Flame Atomic
Absorption spectrometry (FAAS) and by Inductively coupled Plasma Atomic
Emission Spectrometry (ICP-AES). Those of Cd, Cr and Pb determined by
Electrothermal Atomic Absorption Spectrometry with Zeeman correction (ZETAAS).


Use Constraints
none


Keywords
(Sector 1) major and trace elements
(Sector 1) heavy metals
(Sector 1) lichens
(Sector 1) Terra Victoria
(Sector 1) Terra Nova Bay
Lichen U. decussata and surface soil from Victoria Land (Antarctica)


Data Set Progress
COMPLETE


Data Center
Dipartimento di Science Ambientali (G. Sarfatti), Universita Delgi Studi di Siena, Italy    [Information]
Data Center URL: http://www.unisi.it/ricerca/dip/dba/

Data Center Personnel
Name: ROBERTO BARGAGLI
Phone: +39 0577 232828
Fax: +39 0577 232806
Email: bargagli at unisi.it
Contact Address:
via P. A. Mattioli n.4
City: Siena
Province or State: Tuscany
Postal Code: 53100
Country: Italy



Distribution
Distribution_Media: Scientific publications
Distribution_Format: none
Fees: none



Creation and Review Dates
DIF Creation Date: 2004-09-20
Last DIF Revision Date: 2016-01-27



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