Upload
others
View
1
Download
0
Embed Size (px)
Citation preview
2/25/2016
1
Soil Development and
Status
Neil Dominy
State Soil Scientist
Lincoln, Nebraska
www.ne.nrcs.usda.gov
USDA is an equal opportunity provider and employer.
Objectives
Setting the stage for the day
ClORPT
Soil Survey changes
Importance and complexity of Soils!
2/25/2016
2
INTRO Pictures
What is soil?
The unconsolidated mineral or organic material on the immediate surface of the earth that serves as a natural medium for the growth of land plants.
NRCS
2/25/2016
3
Hans Jenny
1941: soil is open system, properties are functionally
related; system changes when property(ies) change(s).
Jenny’s CLORPT equation
s = ƒ (cl, o, r, p, t)
Soil Forming Factors
Soil = CLORPT
Climate
Organisms/Biota
Relief (Topography)
Parent Material;
Time (Stability)
2/25/2016
4
Climate
Climate: Precipitation
http://www.nefb.org/ag-ed/
2/25/2016
5
Climate: Frost Free Days
Climate Resiliency 2012 and 2015
2/25/2016
6
Living Organisms
Organisms Vegetation
Prairie
Trees
Critters that mix the soil
Prairie dogs, gophers
Worms and all the bugs
More organisms in a spoonful of soil than
humans living today
2/25/2016
7
Living Soil
2/25/2016
8
Landscape position
Landscape Position
2/25/2016
9
Landscape Catena
2/25/2016
10
loess
till
eolian sand Soil Parent Materials in Nebraska
2/25/2016
11
TIME
Time
Effects of climate and living organisms, modified by
topography, on the development of soil from parent
material takes time.
Stability of a site is required to provide soil development
2/25/2016
12
Human Influence
Four general Processes of soil formation
Transformation – weathering synthesis of minerals and
decomposition of Organic matter
Translocation – movement of mineral and organic
materials in the developing soil
Addition – of organic matter or by deposition
Loss – leaching of soluble constituents or by erosion
2/25/2016
13
General soil map
NRI Erosion Data
2/25/2016
14
NRI Erosion data
Soil Mapping 1965 to 2004 what has
changed?
2/25/2016
15
Eroded soils correlation 1965 and 2004
ShC2 Sharpsburg silty clay loam, 4 to 6 percent slopes, eroded 7647
Yutan, eroded-Aksarben silty clay loams, 2 to 6 percent
slopes
ShD2 Sharpsburg silty clay loam, 6 to 12 percent slopes, eroded 7646
Yutan, eroded-Judson complex, 6 to 11 percent
slopes
ShD3 Sharpsburg silty clay loam, 6 to 12 percent slopes, severely eroded 7646
Yutan, eroded-Judson complex, 6 to 11 percent
slopes
MnC Monona silt loam, 6 to 12 percent slopes 8125 Pohocco silty clay loam, 6 to 11 percent slopes, eroded
MnC2 Monona silt loam, 6 to 12 percent slopes, eroded 8125 Pohocco silty clay loam, 6 to 11 percent slopes, eroded
MhE2 Monona silt loam, sand substratum, 12 to 30 percent slopes, eroded 8146 Pohocco-Pahuk complex, 11 to 17 percent slopes, eroded
MhC2 Monona silt loam, sand substratum, 6 to 12 percent slopes, eroded 8145 Pohocco-Pahuk complex, 6 to 11 percent slopes, eroded
Current Soil Survey data
2/25/2016
16
Why are surface soils
important
Infiltration
Water holding capacity
Soil Life
Many more!
http://soilquality.org.au/factsheets/w
ater-availability
Silt loam soilAvailable Water holding Capacity (AWC)
(cm H2O/ 25 cm soil)
(in. H2O/ ft. soil)
SOM = 0% 1% 2% 3%
2.3 cm
1.10 in.
3.2 cm
1.54 in.
4.2 cm
2.02 in.
5.1 cm
2.45 in.
Source: Berman Hudson, 1994. JSWC 49:189-194.
soil
matrix
water
Soil organic matter “sponge” water+
2/25/2016
17
Conclusion/Questions
ClORPT
Understanding the Importance of Soil
“Our Soil – A layer of life” MASWCD
More to do!