NSF-OPP/ARCSS-9911122
DATE:	9/3/2001
TO:  	LAII ATLAS Investigators, NSF
FROM:	Wendy Eisner, Jim Bockheim, and Ken Hinkel
RE:	August 2001 Field Activities 

This report briefly describes our summer field season, which took place from
August 6 to August 20, 2001.   The field team consisted of Wendy Eisner, Ken
Hinkel, graduate student Elizabeth Wolfe, undergrad Ben Jones (University of
Cincinnati), Jim Bockheim, Nick Balster and Bledar Lushaj (University of
Wisconsin), Kim Peterson (University of Alaska), and Trent Hayden (University
of Massachusetts).  We conducted a program of basin age verification, soil
sampling, and vegetation description of drained thaw-lake basins between Barrow
and Atqasuk.  This is part of our effort to determine the amount of carbon
sequestered in drained basins, changes in carbon accumulation rates over time,
and to understand the influence of climate on the geomorphological evolution of
lake basins on the Arctic Coastal Plain.  This summer field work served as a
follow-up to our spring coring season, and expanded our study area toward the
south.

We are using Landsat-7 ETM+ data  to map these drained thaw lake basins and
classify them into relative age groups.  Spectral and textural data transforms
were utilized with pattern recognition algorithms to enhance features of the
thaw lake basins associated with age.  In order to test the accuracy of these
algorithms, we visited a total of 35 thaw lake basins within a 50 km radius of
Barrow, re-classifying them on the ground based on vegetation composition and
the degree of basin polygonization.  We found that the original algorithms
produced the correct classification for 65% of the basins, so we are attempting
to fine-tune our image-recognition classification scheme.
Before the field season, we submitted 20 samples for dating of the basin cores
which were drilled in April, 2001.  The resulting dates are highly encouraging,
and appear to verify the original vegetation-based classification scheme.  They
also confirm that our sampling strategy is consistent and reliable. Twenty-five
additional samples have been submitted for radiocarbon dating.
Our findings also confirm that organic C and ground ice increase with time in
the lake basins.  The soils show a remarkable change in degree of development
in relation to basin age.  The thickness of the surface organic layer increases
from <5 cm in the youngest basins to >50 cm in the oldest basins.  Similarly,
the degree of decomposition of the surface organic layers varies from
relatively undecomposed (Oi, fibric layer) in the youngest basins to highly
decomposed (Oa, sapric) in the oldest basins.  Soils are classified as
Aquorthels in the young and medium-aged basins, Historthels in old basins, and
Sapristels in the oldest ("Ancient") basins.  Measurement of total organic
carbon in over 450 samples is in progress. 
As always, BASC and VECO personnel were extremely helpful in arranging
logistical support.