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Soil Resource Assessment To guide production practices. Newell Kitchen USDA-ARS Cropping Systems and Water Quality Research Unit Columbia, MO. Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, 10-11 October 2012, Columbia, MO. - PowerPoint PPT Presentation
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SOIL RESOURCE ASSESSMENT TO GUIDE PRODUCTION PRACTICES
Newell KitchenUSDA-ARS Cropping Systems and Water Quality Research UnitColumbia, MO
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, 10-11 October
2012, Columbia, MO
• 1803 Louisiana Purchase and in 1804 a treaty between U.S. Government and Indian tribes (ignored by many Indians for several decades)
• 1850-1880 Railroads accelerated growth and commercialization
• 1820-30s Land purchase and settlement exploded with most of the public land purchased within these decades.
• With early homesteading, timber was an essential resource used for homes and sheds, tools, cooking, and heating. Thus, most homes were near streams.
• The broad flat grassland was viewed less valuable and was mainly used for free-roam grazing for many decades. • Early in the 1900s the face of the
Midwest rural landscape1. Farms increased in size2. People migrated to cities3. Agricultural mechanization
improved
• This major shift in land use
and intensity in the early 1900’s had an immediate impact on the rivers and streams
• During World War I, corn grain prices soared, and so did corn acreage.
• Extensive flat grasslands were plowed and put into grain production for the first time, typically corn, oats, wheat and a new crop, soybean.
• With the exception of two years, multiple and damaging large flood events caused severe soil erosion and property damage between 1926-1936. Grain crop yields for many fields actually declined when compared to the previous century (Bennett, 1939).
• Since, billions of dollars have been spent on soil and water conservation projects. But with some soils, the damage has been catastrophic and irreparable.
The first erosion plot research in the U.S. was established on the campus of University of Missouri-Columbia, on May 1, 1917.
Where in the Midwest was the negative impact of modern agriculture the greatest?
Cascading Soil Degradation
Poor Land Management Decisions on Sensitive Soil Landscapes
Degraded structure & aggregation
Compaction & crusting Water erosion
Reduced plant growth
Poor soil biology
Decreased yieldReduced Sustainability
1. Lost Topsoil. In less than 150 years, claypan soils have greatly lost topsoil, and consequently other important qualities (e.g.,microbial diversity, structure).
• Average 13 cm (5 in) of soil loss over the whole field. That averages ~7.5 tons/A/yr.
• Areas of extreme have lost 40 cm (16 in).
2. Historical topsoil loss from erosion has greatly impaired claypan soil field productivity, creating “marginal areas ” under some cropping.
3. Soil quality and ecosystem function for claypan soils will not likely improve much under grain cropping practices.
0.8
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Foot slope Back slope Summit
Landscape
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Min. Till CS (1)No Till CS (2)ICM No Till CSW (5)CRP (6)
4. Claypan soils are especially good candidate fields for in-season variable-rate N management, because of the high propensity for denitrification losses.
5. No-till corn-soybean on claypan soils often ends in failure and a return to tillage, because erosion persists. Adding cover crops with no-till is more successful.
6. Depth to the claypan and slope are key soil properties for identifying marginal vulnerable areas within claypan soil fields.
7. No-till cropping increases losses of runoff and soil active herbicides on claypan soils.
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atra
zine
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Plot Study
8. Claypan soil fields exhibit strong spatial patterns of variability for soil properties and crop growth. Important factors include topsoil depth and past practices.
1939 1956 1968 1982 19901939 1956 1968 1982 1990
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lb /A
P o ta ss iu m p H
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P o ta ss iu m p H
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Potassium Phosphorus pH
Topsoil Depth
9. The claypan drives surface hydrology and the environmental problems found on these fields. They behave as if they have much greater slope.
10.Depth of topsoil over the claypan is a strong measure of soil erosion and serves as a useful basis for future crop management planning.
AA
CC
BB
Whole Field:– no-till– grade to remove ponding problems– variable rate P, K, and lime– variable rate N for wheat and corn
Area A. 2-year rotation of wheat-cover crop hay-soybean.– no crop during droughty period– no soil active herbicides– cover crop during high erosion times– perennial crops reintroduced
Area B. Same as A but with waterway grass hedges
Area C. 2-year rotation of corn-soybean
