Future challenges

More variable weather within and among seasons

Warmer temperatures Shifting seasonality of precipitation More demand for food, feed, and fiber

Midwest Corn Grain Production

Year1860 1880 1900 1920 1940 1960 1980 2000 2020

Yiel

d (k

g ha

-1)

0

2000

4000

6000

8000

10000

12000

MichiganIowa

Midwest Soybean Production

Year1920 1940 1960 1980 2000 2020

Yiel

d (k

g ha

-1)

0

500

1000

1500

2000

2500

3000

3500

IllinoisIndiana

Midwest Sweet Corn Production

Year1960 1970 1980 1990 2000 2010 2020

Yiel

d (k

g ha

-1)

1000

1500

2000

2500

3000

3500

MinnesotaWisconsin

Midwest Potato Production

Year1860 1880 1900 1920 1940 1960 1980 2000 2020

Yiel

d (k

g ha

-1)

0

2000

4000

6000

8000

10000

MichiganWisconsin

Figure source: NOAA NCDC / CICS‐NC

Mishra and Cherkauer, 2010

Mean NCCPI

0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Cou

nty

Yiel

d (g

m-2

)

180

200

220

240

260

280

300

320

340

KentuckyIowaNebraska

Kentucky(Double crop)Y = 131.187 + 187.458X. r2 = 0.72***

Soybean yields across Iowa, Kentucky, and Nebraska

NCCPI-AG

0.4 0.6 0.8 1.0

Mea

n C

ount

y Yi

eld

(g m

-2)

500

600

700

800

900

1000

KentuckyIowa

Y = 436.096 + 478.149X, r2 = 0.58***

Iowa Maize Story County

Year1950 1960 1970 1980 1990 2000 2010 2020

Yiel

d (k

g ha

-1)

-2000

0

2000

4000

6000

8000

10000

12000

14000

Attainable YieldActual YieldYield Gap

Iowa Maize Story County

Fraction of Attainable Yield0.0 0.2 0.4 0.6 0.8 1.0

Cum

ulat

ive

Freq

uenc

y

0.0

0.2

0.4

0.6

0.8

1.0

Midwest Corn Production

Year1985 1990 1995 2000 2005 2010 2015

Tota

l Cla

ims

0

1000

2000

3000

4000

5000

Excessive Moisture/PrecipitationDroughtFrost

Midwest Soybean

Year1985 1990 1995 2000 2005 2010 2015

Tota

l Cla

ims

0

1000

2000

3000

4000

5000

Excessive Moisture/Precipitation Drought Frost

Poor Land Management

Aggregation Degradation

Compaction& crusting

Water & Wind Erosion

Plant Growth Soil Biology

Yield

Reduced Soil Productivity

Biological Activity

Improved Nutrient Cycling

Organic Matter Turnover

Improved Soil Structure

Improved WaterAvailability

EfficiencyYieldProfit

We build soil through biological activity not by physical or chemical manipulation

Feeding the complex soil biology working hard for you below the surface.

Crop residue benefits

Simple crop residue on the surface

Organic Matter Effects on Available Water Capacity

Silt loam

OM increase from 1% to 4.5%AWC doubles!

5.7% 22.9% (% by Vol.)

Data from Soil Survey Investigation Reports(surface horizons only)

- Sands: FL (n = 20)- Silt loams: IA, WI, MN, KS (n = 18)- Silty clay loams: IA, WI, MN, KS (n = 21)

Sands AWC = 3.8 + 2.2 (OM) r2 = 0.79

Silt loams AWC = 9.2 + 3.7(OM)r2 = 0.58

Silty clay loams AWC = 6.3 + 2.8 (OM)r2 = 0.76

Hudson, B. D. 1994. Soil organic matter and availablewater capacity. J. Soil Water Conserv. 49(2):189-194.

Will not change the precipitation availability

Will be able to change the soil water availability if we reduce E of ET, residue can reduce the soil water evaporation by 50 to 100%

Increase the soil biology will increase the organic matter content 

Organic Matter (%)0 1 2 3 4 5 6 7

Ava

ilabl

e W

ater

Con

tent

(%)

0

5

10

15

20

25

30

35

Data Points Sand, AWC = 3.8 + 2.2 OMSilt Loam, AWC = 9.2 + 3.7 OMSilty clay loam, AWC = 6.3 + 2.8 OM

Early August Late August

Carbon          Water          Nitrogen

Key ProcessesPhotosynthesis               Precipitation            N FixationRespiration                        Evaporation             MineralizationOrg Matter decomp      Infiltration DenitrificationPlant decomposition     Runoff Plant decomposition

Percolation    

Soil surface

Solar Radiation

Cycles interact over time and space with different rates

Water Cycle

Lal, 2015, JSWC70:82A‐88A

Requires a soil to supply water and nutrients throughout the life cycle of the plant 

Cropping system that can withstand the stresses imposed by variable weather

Requires an integration of genetics and management to offset the environmental impacts (G x E x M) 

Enhancing the soil will increase the capacity of the agroecosystem to be resilient