World Fertilizer N
Consumption and
Challenges
Nitrogen Use Efficiency Conference
Stillwater, Oklahoma
August 3, 2010
C.S. Snyder, PhD, CCA
Nitrogen Program Director
Background
• N is essential to the survival of all life
• Over 40% of the people on Earth owe their
existence to the food production made possible
by N fertilizers
• “Human alterations of the N cycle have caused a
variety of environmental and human health
problems ranging from too little to too much
reactive N in the environment.” (Woods Hole Research
Center)
• half the synthetic N fertilizer ever used
has been utilized since 1985
(Howarth, 2005).
http://www.whrc.org/policy/global_nitrogen.htm
A Growing World Population Requires
an Increased Global Food Supply
”Stewart et al. (2005) reviewed data representing 362 seasons of crop
production and reported at least 30 to 50% of crop yield can be
attributed to commercial fertilizer inputs.”
“…food production will have to increase by 50% by 2013 and
double in 30 years to help solve the current food crisis.”
(Roberts. 2009. Better Crops 93(2):12-15)
World Fertilizer N Consumption, 1961-2007
100
80
Oceania
70
Africa
W. Asia
60
E. Europe & C. Asia
50
L. America & Caribbean
40
W. & C. Europe
30
N. America
S. Asia
20
E. Asia
2007
2005
2003
2001
1999
1997
1995
1993
1991
1989
1987
1985
1983
1981
1979
1977
1975
1973
1971
1969
1967
1965
0
1963
10
1961
Million tonnes of N
90
IFA Statistics 2010
World Fertilizer N Consumption by Source
IFA Statistics 2010
U.S. N Source Consumption: 1970-2007
Source: H. Vroomen -TFI, and AAPFCO
World and U.S. Fertilizer N Consumption
World
U.S.
Source: IFA Statistics, 2010
U.S. Fertilizer N Consumption
0.5% increase per year, since 1980
Acres of corn
grain harvested
(million)
Corn grain Corn grain
yield, bu/A production, bu
(billion)
1981
74.524
108.9
8.119
2008
78.510
153.9
12.092
5%
41%
49%
0.002%
1.5%
1.8%
change
change/yr
Source: AAPFCO and TFI, 2010
Source: Heffer. 2009. Assessment of Fertilizer Use by Crop at the
Global Level: 2006/07 – 2007/08 . IFA. Paris, France
Fertilizer,
Increased N Inputs
and Global N Flows
Pose Environmental
et al. 2008.
Challenges Galloway
Science 320, 889
31 Tg N
Grain, 12 Tg N
Meat, 0.8 Tg N
1 Tg = 1 million tonnes (Mt)
Global N Use Efficiency
• Can be defined many different ways
– Ladha et al. 2005. Advances in Agronomy 87: 85-176.
– Dobermann. 2007.IFA Workshop on Fertilizer BMPs.
Brussels, Belgium. March 7-9, 2007.
• Worldwide fertilizer N use efficiency in cereal
production was estimated at 33% (Raun and
Johnson. 1999. Agron. J. 91:357–363)
– NUE =
(est. grain N removal – (est. N from soil + rainfall))
est. cereal fertilizer N consumption
x 100
Global Nitrogen Use Efficiency,
Expressed as Apparent N Recovery (REN)
• <50% N use efficiency globally by most crops
(Balasubramanian et al., 2004; Ladha et al., 2005)
• typical on-farm REN (Dobermann and Cassman, 2002)
– only 30% in rice and 37% in maize,
– with good management REN could be 50 to 80%
• in cereal crop research
– total REN from a one-time application of N averages 50 to 60%, and
40 to 50% under most on-farm conditions (Dobermann, 2007)
CF Industries
OSU
Kitchen and Goulding (2001) in
Nitrogen in the Environment:
Sources, Problems and Management
• “ nitrogen use efficiency …rarely
exceeds 70% ……. often ranges from
30-60%”
• “conversion of N inputs to products
for arable crops can be 60-70% or
even more”
EPA SAB Integrated N Committee report on reactive N
(Aug. 27, 2009 DRAFT): recommends crop N-uptake efficiencies
increase by up to 25% over current practices, through a combination of
knowledge-based practices and advances in fertilizer technology
How Much N Loss via Major Pathways ?
• Runoff, leaching and
drainage
• Ammonia volatilization
• Denitrification and N2O
emissions (direct and
indirect)
Education & Natural Resources District
Regulation Help Lower Groundwater NO3
Central Platte Valley, Nebraska
180
40
NORTH
N Fertilizer Applied
N price doubles
N (lbs/acre)
120
30
100
N Removed in Grain
y = 1.8242x - 3517.2
R² = 0.4484
α = 0.01
80
25
Groundwater N
y = -0.2369x + 495.89
R² = 0.8657
α = 0.001
60
40
1985
1987
1989
1991
1993
1995
1997
1999
2001
2003
2005
20
2007
20
200
Irrigation Water: NO3-N = -0.1142x + 245.55
R² = 0.68
18
180
160
140
16
120
100
14
80
60
12
Soil Residual NO3-N = -1.7725x + 3627.7
R² = 0.42
40
20
10
1985
0
1990
1995
2000
2005
Source: Personal communication with Richard Ferguson (2010)
For more info refer to Exner et al.2010. The Scientific World Journal 10:286-297.
2010
Soil Residual NO 3 -N (kg ha-1 )
35
140
Groundwater Nitrate-N (mg/L)
y = 0.3668x - 591.26
R2 = 0.0464
Irrigation Water NO 3-N (mg L-1 )
160
River N Flux is Predicted to Increase with
Increased N Inputs (Bouwman et al., 2005)
Global N Input
River N Flux
600
60
transition
country
industrialized
country
400
developing
country
300
200
100
50
River N flux, Tg per yr
N input, Tg per year
500
transition
country
industrialized
country
40
developing
country
30
20
10
0
0
1970
1995
2030
1 Tg = 1 million tons (Mt)
1970
1995
2030
USGS Estimates of Loss and Delivery of
N and P to the Gulf of Mexico
SPARROW - Modeled Estimate of N and P
Discharge in Watersheds of the Mississippi R. Basin
kg/ha
.01
.01- 0.1
0.1 to 1
1 to 5
5 to 10
>10
kg/ha
.001
.001- 0.01
0.01 to 0.1
0.1 to 0.5
0.5-1.0
>1
Alexander et al. Environ. Sci. Technol. 2008, 42, 822–830
Gulf of Mexico Hypoxia Area
new Aug. 2, 2010
2015
Hypoxia
Goal
15
No Data
Square miles of hypoxia
Year
Hypoxia data from N. Rabalais, LUMCON
Hypoxic Zones Are Increasing Globally
Diaz and Rosenberg. 2008.
Science 321:926-929
NH3 Volatilization Losses from N Fertilizers
• Up to 45% of the urea-N applied under surface-applied,
warm, moist field conditions can be lost as NH3(Watson,
2005)
• Volatilization of NH3 from N fertilizers has been estimated
by Bouwman et al. (2002) at:
– 18% in developing countries, based on N sources used and
environmental conditions,
– 7% in industrialized countries
– Estimated global median NH3 loss
• 14% for fertilizer N
• 23% for manure N
• NH3 volatilization loss has exceeded
– 50% of applied urea N in transplanted rice paddy systems in Asia
– 30% of the applied N if flooding is delayed for up to 14 days after
urea is surface broadcast in drill-seeded flood-irrigated rice
2008 Total U.S. GHG Emissions,
based on CO2 equivalents
Agriculture share
6% of all U.S. GHG emissions
2007 Total EU-27 GHG Emissions,
based on CO2 equivalents
Agriculture share
9% of all EU-27 GHG emissions
Radiative Forcing (GWP)
N2O x 296 = CO2e
CH4 x 23 = CO2e
U.S. EPA Inventory of GHG Emissions
and Sinks,1990 – 2008 (2010)
European Environment Agency. 2010. Greenhouse
gas emission trends and projections in Europe 2009
U.S. GHG Emissions & N2O from
Ag Soil Management
(EPA 2010 U.S. GHG inventory, 1990-2008)
3.9%
3.7%
3.3%
3.5% 3.5%
3.4%
3.6%
Ag soil mgmt.
4% in EU-27
in 2007
Agricultural soil management N2O as
portion of total U.S. GHG emissions
Agricultural soil management includes fertilizer application and
cropping practices; the largest sources of N2O emissions,
accounting for 68% of all U.S. N2O emissions in 2008
1 gigaton (Gt) = 109 tonnes = 1012 kg = 1015 g = 1,000 Tg = 1018 g
1 terragram (Tg) = 1012 g = 109 kg =106 tonnes
Source: Flynn and Smith. 2010. Greenhouse gas budgets of crop
production – current and likely future trends. IFA. Paris, France
Nitrous Oxide (N2O) Emissions from
Agricultural Soils, 1990-2020 (EPA, 2006)
4R Nutrient Stewardship
Crops & Soils 42(2): Mar-Apr 2009
http://www.ipni.net/4r
Crops & Soils 42(3): May-Jun 2009
Crops & Soils 42(4): Jul-Aug 2009
Know Your Fertilizer Rights: Right Place
Crops & Soils 42(5): Sep-Oct 2009
by T.S. Murrell (IPNI), G.P. Lafond (AAFC), and T.J. Vyn (Purdue U.)
Crops & Soils 42(6): Nov-Dec 2009
Agriculture, Ecosystems and Environment
(2009) 133:247-266.
Fertilizer N : source, rate, timing, and place of application
N Rates Used by Farmers on Corn ?
USDA NASS/ERS and Corn N Rate Calculator
• USDA: average N rate applied for corn in 2000-2005 was
135 lb/A (151 kg/ha)
• N Rate Calculator: @ $0.36/lb of N and $3.60/bu of corn:
2005 applied,
MRTN, lb N/A
lb N/A (NASS)
–
–
–
–
–
–
Illinois
Indiana
Iowa
Michigan
Minnesota
Ohio
• 6-state ave. =
168
171
125
130
105
174
146
147
141
128
139
161
146
144
Fertilizer N Effects on Profile SOC
After 39 Years of Continuous Corn with a
Winter Cereal Cover Crop
Grove et al. 2010. Better Crops 93(4):6-8
Duration III and ESN = Polymer Coated
urea
SuperU and UAN+AP contain urease
and nitrification inhibitors
20 to 50 %
reduction
possible with N
source
selection
192 bu/A
1 Mg/ha =15.9 bu/A
Corn grain yield (Mg/ha) is shown near the bottom of each bar
Source: Halvorson et al., 2009 Better Crops 93(1):16-18; Submitted to JEQ on Feb. 1, 2010.
N Source Affects Growing Season N2O
and CO2 Emissions, and Corn Yields (MN)
•N rate = 146 kg N/ha,
in spring 1-2 weeks
before planting:
•NH3 knifed, urea
bdcst. & incorporated
N2O emissions with urea
were half of those with
anhydrous ammonia
“It is likely that the effects
of fertilizer form will be
site specific and depend
to some extent on soil
pH.”
Venterea et al. 2010. Soil Sci. Soc. Am. J. 74:407–418
N2O Emissions Tend to Increase
as N Rates Increase
(Halvorson et al., 2009. Better Crops 93:16-18)
N Rate Effects on Daily N2O Flux
in Corn (8-site-years, MI)
Millar et al. 2010. Mitig. Adapt. Strateg. Glob. Change. 15:185–204.
Is Lower Input, Less Intensive Ag the Answer?
Snyder et al. 2009. Agric. Ecosyst. Environ. 133:247-266
More Intensive Systems Can Help Lower
GWP per Unit of Food Produced
- Ecological Intensification State
Rotation &
System
Tillage
Food Yield,
Gcal/ha/yr
N2O
GWP/Food
Yield
MI
C-S-W
CT
12
43
95
MI
C-S-W
NT
13
43
11
MI
C-S-W low input
w/legume
CT
12
50
53
MI
C-S-W organic
w/legume
CT
9
62
46
NE
C-C BMP
CT
48
24
41
NE
C-C intensive
CT
51
41
60
NE
C-S BMP
CT
35
26
107
NE
C-S intensive
CT
37
34
101
Snyder et al. 2009. Agric. Ecosyst. Environ. 133:247-266
Net
GWP/Food
Yield
More Intensive Systems Can Help Lower
GWP per Unit of Food Produced
State
Rotation &
System
MI
C-S-W
MI
Tillage
Food Yield,
Gcal/ha/yr
N2O
GWP/Food
Yield
Net
GWP/Food
Yield
CT
12
43
95
C-S-W
NT
13
43
11
MI
C-S-W low input
w/legume
CT
12
50
53
MI
C-S-W organic
w/legume
CT
9
62
46
NE
C-C BMP
CT
48
24
41
NE
C-C intensive
CT
51
41
60
NE
C-S BMP
CT
35
26
107
NE
C-S intensive
CT
37
34
101
4X
more
food
Snyder et al. 2009. Agric. Ecosyst. Environ. 133:247-266
The Key is to
Limit Potential
“Surplus N”
“ … agricultural
management
practices to reduce
N2O emissions
should focus on
optimizing fertilizer-N
use efficiency under
median rates of N
input, rather than on
minimizing N
application rates.”
Van Groenigen et al. 2010. Europ. J. Soil Sci. doi: 10.1111/j.1365-2389.2009.01217.x
Will Variable-Rate N Using Canopy
Sensors Deliver Environmental Benefits?
Source: Roberts, Kitchen, Scharf & Sudduth. 2010. Agron. J. 102: 85-95
Each dollar invested in higher crop yields has
resulted in 68 fewer kg of C (249 kg CO2e) emitted.
Stanford University
Source: Burney et al. 2010. Proc. Natl. Acad. Sci. 107(26):12052-12057
A Preliminary
Nutrient Use Geographic
Information System (NuGIS)
for the U.S.
2010
Estimated N balance by watershed, 1987.
IPNI, 2010
Estimated N balance by watershed, 1992.
IPNI, 2010
Estimated N balance by watershed, 1997.
IPNI, 2010
Estimated N balance by watershed, 2002.
IPNI, 2010
Estimated N balance by watershed, 2007.
U.S. Partial N Balance
IPNI, 2010
1987
31.2 lb/A
1992
33.6
1997
32.4
2002
32.8
2007
35.3
Improving N Use Efficiency
• Implementation of fertilizer best management practices
(BMPs)
• Site-Specific Nutrient Management (SSNM) - to help
achieve improved economic results and environmental
objectives
Thank You
Better Crops, Better Environment … through Science
www.ipni.net