|
CALM SITE U17 |
WICKERSHAM |
|
Site code |
U17 |
|
Site name |
Old Man Grid |
|
CAPS I Metadata
form |
GGD355 |
|
CAPS II Metadata
form |
GGD313U_17 |
|
Responsible for
data submission |
Karl Olson |
|
Email Address |
kdolson@alaska.edu |
|
Institution/Organization |
|
|
Location
description |
Subarctic Alaska |
|
Location Lat. |
65 deg. 6 min. N |
|
Location Lon. |
148 deg. 03 min. W |
|
Elevation avg.
(m) |
335 |
|
Methods Grid |
|
|
Methods Other |
20 m transect, Air Temperature,
Soil temperature |
|
Landscape
Description |
Foot of long west-facing slope |
|
Vegetation
/Classification |
Open black spruce forest |
|
Soils (or
Material) |
Histic Cryaquept |
|
Thaw depth
measurements (year started)
|
1971 |
|
Air temp.
measurements (year started) |
NA |
|
Snow cover
measurements (year started) |
NA |
|
soil temp. measurements (year started) |
1975-1983 |
|
soil moisture
measurements (year started) |
NA |
|
general
description of soil moisture (dry, moist, wet, saturated) |
Moist |
|
soil texture: if
non organic describe texture, if organic indicate thickness of organic layer
(cm) |
silt loam (a Histic Cryaquept (USDA 1975) |
DESCRIPTION
OF AREA CONTAINING SITE:
The
Wickersham CALM site was established as part of a major fire-effects study
conducted by the Institute of Northern Forestry following the 1971 Wickersham
Fire.
As
part of these studies a series of thaw probe lines were established to follow
the changes in the active layer as a result of the fire and fireline
construction. Details of the fire and related studies were presented by Viereck and Dyrness (1979). The
data for the Wickersham CALM site comes from an undisturbed black spruce stand
that was established as a “control” for the studies of active layer
changes in the burned and fireline areas.
The
Wickersham site is approximately 50 km northwest of Fairbanks and adjacent to
the Elliot Highway. (65 o 10’N: 147 o 54’W)
The probe line is at an elevation of 335 m near the foot of a long west-facing
slope. The vegetation along the probe line is an open black spruce forest type
(Open Picea mariana/Ledum groenlandicum/Sphagnum
spp-Cladonia
spp community) (Viereck
et al 1993). The black spruce have a density of 1240 trees/ha and 45% canopy
cover. Average diameter of the trees in 1971 was only 5.2 cm. A detailed
description of the vegetation at the site can be found in Viereck,
1982.
SOIL
DESCRIPTION: (predominant texture, i.e., ‘sand’,
‘gravel’, ‘peat’, etc.):
The
soil at the site is a Saulicch silt loam (a Histic Cryaquept (USDA 1975).
These are poorly drained soils formed of a silty loam more than 75 cm in depth
with a shallow active layer. There is a moss-litter layer (01 and 02) of 25 to
30 cm underlain by approximately 10 cm of a dark grayish-brown silty loam A horizon over a frozen C horizon of olive-gray silty loam.
SAMPLING DESIGN AND METHOD:
A probe line
20 meters long was established parallel to the slope: 10 probing sites at
2-meter intervals were permanently marked along the line. A trail was
established below the line to avoid disturbance of the vegetation at each of
the probe sites. For the first four years of the
study the active layer was measured at two-week intervals. Starting in 1975
soil temperatures were also taken at two-week intervals at depths of 5, 10, 20,
and 50 cm with a steel probe with a thermistors at the tip. In 1978 a set of
thermistors was installed near one end of the probe line at depths of 5, 10,
20, 50, and 90 cm and were read weekly or biweekly. In addition, in October of
1978 a thermograph and weather station were installed at the site to record air
temperatures. Snow depth was measured throughout the winter using two permanent
snow poles. These
weekly observations were continued through October of 1983. After that the
active layer was measured at the ten points along the probe line once a year,
usually in mid September.
REFERENCES:
Viereck, L. A., Effects of fire and firelines on active layer thickness and soil temperatures
in interior Alaska, in Proceedings of the 4th Canadian Permafrost Conference,
The Roger J. E. Brown Memorial Volume, pp. 123– 134, Natl. Res. Counc. of
Viereck,
Viereck,
Only
thaw depth data determined by mechanical probing is reported on CALM website.
For additional data contact site investigators directly