Rates of Soil Processes in
Reclaimed Lands
Eric C. Brevik
Dickinson State University
Soil Formation
• Natural soil formation at any given place is
controlled by the five soil forming factors:
1.
2.
3.
4.
5.
Parent material
Organisms
Topography
Climate
Time
• Soil formation rates in newly exposed parent
materials tend to be high and decline with
time/depth (Brevik, 2013; Troeh et al., 2004)
300
Natural Soil Formation Rates
Soil Depth (cm)
250
200
150
R² = 0.3748
100
50
0
0
10000
20000
30000
40000
50000
Years of Soil Formation
Natural Soils
Log. (Natural Soils)
60000
70000
80000
Natural Soil Formation Rates
50
45
40
Soil Depth (cm)
35
R² = 0.5006
30
25
20
15
10
5
0
0
20
40
60
80
100
Years of Soil Formation
Natural 160
Log. (Natural 160)
120
140
160
Reclaimed Soil Formation
• In reclaimed lands, the 5 traditional soil
forming factors are not easily applied
(Sencindiver and Ammons, 2000)
– The time factor is extremely short
– Topography is due to earth-moving equipment,
and does not predict spatial variations in parent
material properties
– Human actions have a major influence on soil
formation rates
Reclaimed Soil Formation
• Soil formation can occur very rapidly in
shallow reclaimed soils:
– A horizons greater than 5 cm can form in 3
years or less (Roberts et al., 1988)
– C content of upper 10 cm may equal
surrounding native soils in 30-50 years
(Sencindiver and Ammons, 2000)
– Physical and chemical weathering breaks down
rock fragments very rapidly in the upper few cm
(Ciolkosz et al., 1985)
Reclaimed Soil Formation
• Soil formation below 10 cm takes place very
slowly
– 400 years or more may be required to reach
organic C levels comparable to native soils
(Sencindiver and Ammons, 2000)
• This is similar to studies of natural soil
formation, where deep soil processes take long
periods of time (Brevik, 2013; Troeh et al.,
2004)
– 1000 years to form 1 inch of soil is for a depth of
~40 inches
Reclaimed Soil Formation Rates
Random Sites
50
Soil Depth (cm)
40
30
y = 4.0563ln(x) + 9.6702
R² = 0.0609
20
10
y = 4.5706ln(x) - 4.4541
R² = 0.7394
0
0
5
Reclaimed Soils
10
15
20
Years of Soil Formation
Natural Soils
Log. (Reclaimed Soils)
25
Log. (Natural Soils)
30
Reclaimed Soil Formation Rates
Common sites
20
18
16
y = 4.4778ln(x) + 3.2308
R² = 0.6509
Soil Depth (cm)
14
12
10
y = 2.6296ln(x) + 0.9751
R² = 0.7943
8
6
4
2
0
0
5
Reclaimed Soils
10
15
20
Years of Soil Formation
Natural Soils
Log. (Reclaimed Soils)
25
Log. (Natural Soils)
30
60
Soil Formation Rate by Reclamation
Method
Soil Depth (cm)
50
40
30
y = 4.3468ln(x) + 6.673
R² = 0.0478
20
y = 4.91ln(x) + 3.6401
R² = 0.1678
10
0
0
5
10
15
20
Years of Soil Formation
Plantings Only
Fertilizer and/or OM
Log. (Plantings Only)
Log. (Fertilizer and/or OM)
25
30
Other Ways to Quantify Reclamation
• Several other measures are frequently used to
quantify the relative success of soil reclamation
efforts:
–
–
–
–
–
–
–
Organic C and N accumulation in the soil
Reduction in bulk density and void creation
Formation of soil structure
Improvements in pH and/or base saturation %
Crop yields or above ground biomass production
Plant species diversity
Measures of microbial activity
Other Ways to Quantify Reclamation
• Alexander (1989) investigated reclamation of
tin mines over 23 years using plantings of
eucalyptus trees in Nigeria; no lime, fertilizer,
or OM additions utilized
• Noted an increase of 0.008-0.010% organic C
per year with reclamation and 0.006-0.008%
organic C per year without reclamation
• Also noted decreased pH and base saturation
under eucalyptus, leading to soil degradation
• Selection of reclamation techniques is
important
Other Ways to Quantify Reclamation
• Pietrzykowski and Krzaklewski (2007)
investigated reclamation of sand quarries in
Poland over 25 years using native tree species
and OM, lime, and fertilizer additions
• Organic C increased 0.031-0.039% per year
with reclamation and 0.029-0.032% per year
without reclamation
• Total N increased 0.0020-0.0038% per year
with reclamation and 0.0013-0.0022% per year
without reclamation
Conclusions
• Reclamation efforts can improve soil properties
versus natural succession
• Rates of horizon development may not
increase under reclamation, but the initial
parent material conditions can be improved
• Rates of soil formation decrease with time in
both natural and reclaimed environments
• It is important to carefully consider
reclamation techniques, as there are some
examples of situations where reclamation may
have actually set the soil back
References
Alexander, M.J. 1989. The long-term effect of Eucalyptus plantations on tin-mine spoil and
its implication for reclamation. Landscape and Urban Planning 17:47-60.
Brevik, E.C. 2013. Forty years of soil formation in a South Georgia, USA borrow pit. Soil
Horizons 54(1): doi:10.2136/sh12-08-0025.
Ciolkosz, E.J., R.C. Cronce, R.L. Cunningham, and G.W. Peterson. 1985. Characteristics,
genesis, and classification of Pennsylvania minesoils. Soil Science 139:232-238.
Pietrzykowski, M., and W. Krzaklewski. 2007. Soil organic matter, C and N accumulation
during natural succession and reclamation in an opencast sand quarry (southern Poland).
Archives of Agronomy and Soil Science 53(5):473-483.
Roberts, J.A., W.L. Daniels, J.C. Bell, and J.A. Burger. 1988. Early stages of mine soil genesis
as affected by topsoiling and organic amendments. Soil Science Society of America Journal
52:730-738.
Sencindiver, J.C., and J.T. Ammons. 2000. Minesoil genesis and classification. In: Reclamation
of drastically disturbed lands. Agronomy Monograph No. 41, ASA, CSSA, SSSA, Madison, WI,
USA. p. 595-613.
Troeh, F.R., J.A. Hobbs, and R.L. Donahue. 2004. Soil and water conservation for productivity
and environmental protection, 4th ed. Pearson Prentice Hall, Upper Saddle River, NJ.