Long Term Ecological Research (nematode experimental area) site investigation of soil properties; this site (LTER 4) was selected for repeat sampling to measure changes in soil moisture adjacent to a retreating snow bank; the snow edge on day 9 was 54cm from the saampling transect
Description:
North side of the LTM Datalogger plot, approximately 100m south of Lake Hoare, on the lower slope of a shallow gully which forms part of an undulating ridge and gully/basin topography; the site is a fine gravelly toe slope surface and is immediately adjacent to a snow patch which was retreating; this site is approximately 25m to the east of LTER 1
Altitude:
90 m
Aspect:
N
Slope:
2 °
Location Data
Observer
IBC
GPS
Yes
Latitude Longitude DMS
77° 37.99' S 162° 52.92' E
Latitude Longitude DD
-77.63320 162.88200
Latitude longitude precision DD
0.00008 0.00008
Locality
Near Lake Hoare, Taylor Valley, McMurdo Dry Valley region, Transantarctic Mountains
Survey
Lake Bonney Quadrangle, Antarctic 1:50,000 Topographic Series, USGS 1975
Climate
Soil climate zone:
Coastal mountain;
Estimated mean annual temperature:
-20
°C
Frozen ground depth:
0 Nd
Frozen type:
Nd
Frozen comment:
Nd
Geology
Geological setting:
The deposit is unweathered Ross I till, possibly derived from the Canada Glacier but almost certainly with an up-valley influence because of the presence of marble clasts from basement rocks; the tills may be fluvio-glacial owing to complex depositional ice-marginal processes as the sand % generally increases downwards while there are noticeably more coarse clasts at the surface
Patterned ground:
Weakly developed 15m net with 30cm trough width, 10cm deep
Surface weathering or surface features:
A pebble pavement surface with few weathering features
Soil
Soil parent material:
Predominantly granite/gneiss/schist sandy gravel with minor amounts of dolerite, volcanic (scoria), sandstone and marble
Previous disturbance:
Site probably disturbed by foot traffic activity during biological research activities near the site
Xerous to subxerous; a moist site; the snow patch adjacent to the sampling transect was continuing to thaw
Biological activity:
Nil observed at site, nematodes present in adjacent soil; some green algae beneath marble clasts in the general area
Profile Description
Horizon
Depth
Description
884a
0
–
2
cm
moist; rock particles subangular to subrounded; some carbonate coatings; diffuse boundary,; light olive grey to pale olive (5Y 6/2 - 6/3) pebbly sandy gravel; loose to weakly cohesive
884b
2
–
5
cm
light olive grey to pale olive (5Y 6/2 - 6/3) pebbly sandy gravel; loose to weakly cohesive; moist; rock particles subangular to subrounded; some carbonate coatings; diffuse boundary