RECOVERY OF

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RECOVERY OF DISTURBED AND RECLAIMED SOILS IN
NORTHEASTERN WYOMING P.D. Stahl, A.F. Wick, S.
Dangi, V. Regula, L.J. Ingram, D.L. Mummey, U.
Norton Dept. of Renewable Resources,
University of Wyoming Dept. of Crop and Soil
Environmental Sciences, Virginia Polytechnic
Institute Dept. of Biology, California State
University, Fresno Dept. of Biology, Idaho State
University Dept. of Biology University of Montana
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Reclamation and Long Term Recovery
Photo by L. Ingram
Jacobs Ranch Mine Pit
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Soil properties and processes examined by the
Soil Ecology Lab at the University of Wyoming
Biotic Components Processes Plant Community
Structure Biomass Production Microbial
Community Structure Carbon Cycling Arthropod
Community Structure Nitrogen Cycling Nematode
Community Structure
SOM Production Nematode Community
Structure Water Capture and Storage Abiotic
Components Soil Physical Properties Soil Chemical
Properties CHRONOSEQUENCES Soil Organic Matter
Content Quality
Reclaimed Seminoe 1 surface coal mine near Hanna,
WY Photo by J. Anderson
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OBJECTIVE Present the results of our studies on
the recovery of reclaimed soils in Wyoming.
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Microorganisms
Total Microbial Biomass
Actinomycetes
Gram Positive Bacteria
Gram Negative Bacteria
0.8 yr 15 yr 27 yr
undisturbed 0.8 yr
15 yr 27 yr undisturbed

Time after Reclamation
Recovery of the soil microbial community with
time after reclamation
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Microorganisms
Saprotrophic Fungi
Arbuscular Mycorrhizal Fungi
0.8 yr 15 yr 27 yr
undisturbed 0.8 yr
15 yr 27 yr undisturbed

Time after Reclamation
Recovery of the soil microbial community with
time after reclamation
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Arthropods

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Nematodes

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General Soil Properties
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Table 1. Coefficients of variation for soil
properties in reclaimed and undisturbed soils.
Soil Property Reclaimed
Undisturbed and Mine______________
0-5 cm 5-15 cm
_______ 0-5 cm _ 5-15 cm
----- coefficient of
variation ()----- pH Mine 1
3
2 6 4 Mine 2 4 3 8 5
electrical conductivity Mine
1 24 26 41 36 Mine
2 34 25 43 35 bulk density
Mine 1 6 9 25 10 Mine
2 7 3 11 11 organic carbon content
Mine 1 59 76 97 79 Mine
2 76 101 22 46 total carbon
content Mine 1 35 64 43 79
Mine 2 93 37 21 31 total nitrogen
content Mine 1 7 35 37 54
Mine 2 18 39 15 21 microbial
biomass content Mine
1 31 42 58 56 Mine
2 171 320 338 179 AMF biomass content
Mine 1 38 58 64 116
Mine 2 24 48 45 81 Collembola (springtail)
numbers Mine 1 150 91 157 57
Mine 2 64 66 125 70 nematode
numbers (bacterivores) Mine
1 70 63 71 74 Mine
2 73 57 47 73 __________________________________
__________________________________________________
________ Numbers in bold indicate the
highest coefficient of variation value for a
given soil property, depth and Mine.
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Soil Aggregates
(250-2000 µm)
(iPOM)
(LF, least protected)
(mM, most protected)
(53-250 µm)
(LF)
(iPOM)
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Aggregate Size Distribution
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Light Fraction Soil Carbon
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Light Fraction from Density Flotation
lt1 year reclamation
Native Site
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Soil Aggregate Carbon and Nitrogen
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Laboratory values for N-mineralization Mine
4-site 1 was an overburden site
Potentially Mineralizable Nitrogen
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ECOSYSTEM RECOVERY
POSSIBLE FUTURE RESTORED STATES
CURRENT STATE OF RECLAIMED SITES
TIME ?
PRE-MINING UNDISTURBED STATE
Biomass Production, Nutrient Flux, Energy Flow
ECOSYSTEM FUNCTION
CLIMATE CHANGE INVASIVE SPECIES SOIL
DEVELOPMENT SUCCESSION MANAGEMENT
DISTURBED STATE
Species and Complexity
ECOSYSTEM STRUCTURE
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CONCLUSIONS

• Our data indicate that reclamation practices
  result in recovery of the soil organisms we have
  examined.
• Our results show mitigation of soil environmental
  conditions through time towards those of
  undisturbed soil. (spatial variability?)
• Our studies of ecosystem processes (e.g. biomass
  production, carbon cycling, aggregate
  development, water infiltration) indicate they
  are they are returning to function similar to
  undisturbed systems.
• SOILS ARE RESILIENT !

Reclaimed open coal pit! Dave Johnson Mine near
Glenrock, WY Photo by A. Wick
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FUNDING SOURCES Office of Surface
Mining USDA-National Research Initiative National
Science Foundation Abandoned Mineland Research
Program - WYDEQ USDOE