Soils Cubed
Purpose: To evaluate the effects of ecosystem disturbance and soil
type on soil nutrient cycling (N and P) in two forest
ecosystems.
Study sites:
Gadway - Jack pine barrens ecosystem
Minimally disturbed by ice storm of 1998
Ricker Rock Outcrop soil series
Family?
5-15 cm total soil depth to sandstone bedrock
2-3 cm of mineral soil (E horizon).
Altona
- Jack pine barrens ecosystem
Extensively disturbed by ice storm of 1998
Ricker Rock Outcrop soil series
Remediation logging in summer of 1998
5-15 cm total soil depth to sandstone bedrock
2-3 cm of mineral soil (E horizon).
Hardwood – Sugar maple and ??
Deep, well drained soils, stony
Soil series?
Soil Family?
No logging following icestorm disturbance.
Methods:
-
Intact soil cores (20cm x 20cm x 20cm) constructed of 1/8”
plexiglass
Drain holes along one side
Extracted by sinking core through soil as roots and soil cut by
knife
Watered daily with 100 – 200 ml of an artificial acid rain
solution.
200 ml represents 0.5 cm of rain (~.2 in.) each day
Approximately 125 ml leached out of core each day, the rest
lost to evapotranspiration - nutrients concentrated.
NH4+ measured conductimetrically on a Wescan ammonia
analyzer.
NO3-, SO42- and Cl- measured on a Dionex ion chromatograph.
Soluble phosphate measured using the ascorbic acid procedure
(Standard Methods) on a spectophotometer at 880 nm.
Total soil nitrogen measured by digestion in H2SO4/H2O2,
followed by analysis of NH4+ with a Wescan ammonia analyzer.
PH measured with a glass electrode
-
Previous Results:
Concentration of Ortho-P (ppb)
200
n=2
180
160
140
191.55
120
100
80
60
40
20
n=4
n=8
0
Gadway
Uncut
Cut
Site
Fig. ? Soluble phosphate concentrations draining seeps on July 2,
2001 in Undisturbed (Gadway), North Altona (Uncut) Icestorm
disturbed but uncut sites, and Altona Icestorm disturbed and
restoration harvested sites (Cut)
Precipitation
7
6
5
4
Nitrate
3
2
Sulfate
Chloride
1
0
Seeps
Site
7
6
5
4
Chloride
Sulfate
3
2
1
Nitrate
0
Site
Fig ? Anion concentrations (ppm) in precipitation at the Gadway site
(undisturbed), North Altona (Icestorm disturbance only), and Altona sites
(Ice storm and remediation logging; 2 and 3 year old cuts, respectively).