Phase 5 Nutrient Land Calibration
24
Phase 5 Nutrient Land Calibration Jing Wu 04/04/2006 Modeling Subcommittee
description
Phase 5 Nutrient Land Calibration. Jing Wu 04/04/2006 Modeling Subcommittee. Calibration Targets – 8 for each land use. NH 3 NO 3 Labile ORGN Refractory ORGN. }. SURFACE. INTERFLOW. (“slow” surface flow). lower soil layer. NH 3 NO 3 Labile ORGN Refractory ORGN. Groundwater. - PowerPoint PPT Presentation
Transcript of Phase 5 Nutrient Land Calibration
Phase 5 Nutrient Land Calibration
Jing Wu
04/04/2006
Modeling Subcommittee
Calibration Targets – 8 for each land use
SURFACE
INTERFLOW
Groundwater
}NH3
NO3
Labile ORGNRefractory ORGN
NH3
NO3
Labile ORGNRefractory ORGN
(“slow” surface flow)
lower soil layer
• Decision rules developed to relate each target to relevant parameters
- Parameters in the first two layers affected
surface loading
- Parameters in the 3rd and 4th layer affected
below surface loading
Calibration Strategy
• Only two land uses tested
• Most EoF targets not reached
• Suggested changes on application data, EoF targets, and different decision rules
Results for forest
0
20
40
60
80
100
BNH4 BNO3 BLON BRON SNH4 SNO3 SLON SRON
Status at last meeting:
Results for hwm
0
20
40
60
80
100
BNH4 BNO3 BLON BRON SNH4 SNO3 SLON SRON
• Application data (timing, plant uptake curve, etc..)
• EoF targets TN remains same, changes in break-up between different
species
Surface: NH3/NO3 = 1:10
Subsurface: NH3/NO3 = 1:5
• Calibration strategy – decision rules different for different land uses
- forest
- crop, hay
Changes made since last meeting:
Forest Calibration
• Targets changed based on literature values and P4.3 results
TN = 1.7(lbs/acre/yr), same targets everywhere
• Same decision rules as applied before
0
20
40
60
80
100
BNH4 BNO3 BLON BRON SNH4 SNO3 SLON SRON TN
Crop calibration
Three goals need to be accomplished:
1. EoF loads within reasonable range of targets
2. Plant N uptake simulated correctly, within
reasonable range of observed data (critical,
account for most of N loss)
3. Stable N storage over time
Calibration Strategy
• Optimize parameters as did for Forest
- to reach EoF targets
• Optimize initial storages for labile and refractory organic nitrogen
- to eliminate huge spike at the first year due to
high initial storage
- to stabilize storage over time
Export of TN through Time
0
20
40
60
80
100
120
1982 1984 1986 1988 1990 1992 1994 1996 1998 2000
Ann
ual e
xpor
t of T
N
Balanced TN ExportTN Export
Related initial storage to organic N export at the first three years
Storage of nitrate and organic N vs time
0
100
200
300
400
500
600
1982 1984 1986 1988 1990 1992 1994 1996 1998 2000
Sto
rage
on
Jan
1
Nitrate Storage
Labile Organic Storage
Balanced Nitrage Storage
Balanced Labile Organic Storage
Calibration Strategy (cont.)
• Improve simulation on crop uptake
- Change the timing of application data
- Return 60% plant N to refractory organic N
. act as a way to harvest plant
(will increase refractory organic N export,
though)
Old data
Application timingcloser to uptake
After fixed storage and plant N return
0
30
60
90
120
150
0 50 100 150 200 250 300Segment
An
nu
al N
up
take
(lb
s/yr
)
Observed
Simulated
0
30
60
90
120
150
180
0 50 100 150 200 250 300Segment
An
nu
al N
up
take
(lb
s/yr
) Observed
Simulated
0
30
60
90
120
150
180
0 50 100 150 200 250 300Segments
An
nu
al N
Up
take
(lb
s/yr
) Observed
simulated
Percent of each crop
hom
hwm
lwm
50%
8%
42%
High till with manure
0
20
40
60
80
100
BNH4 BNO3 BLON BRON SNH4 SNO3 SLON SRON TN
% o
f seg
men
ts r
each
ed
targ
et
0
30
60
90
120
150
180
0 50 100 150 200 250 300Segments
An
nu
al N
Up
take
(lb
s/yr
) Observed
simulated
High till without manure
0
20
40
60
80
100
BNH4 BNO3 BLON BRON SNH4 SNO3 SLON SRON TN
% o
f seg
men
ts r
each
ed
targ
ets
0
30
60
90
120
0 50 100 150 200 250Segment
An
uu
al N
up
take
(lb
s/yr
)
Observed
Simulated
Low till with manure
0
20
40
60
80
100
BNH4 BNO3 BLON BRON SNH4 SNO3 SLON SRON TN
% o
f seg
men
ts r
each
ed
targ
et
0
40
80
120
160
200
0 50 100 150 200 250Segment
An
nu
al N
up
take
(lb
s/yr
) Observed
Simulated
0
20
40
60
80
100
BNH4 BNO3 BLON BRON SNH4 SNO3 SLON SRON TN
0
20
40
60
80
100
BNH4 BNO3 BLON BRON SNH4 SNO3 SLON SRON TN
Comparison of regular crop and nutrient management crop
• Test model’s capacity of simulating management actions
• Use the calibrated land parameters to run nutrient management land
• TN and plant uptake compared
Comparison of hom and nho
0
20
40
60
80
100
120
0 50 100 150 200 250Segment
An
nu
al N
up
take (
lbs/y
r) hom_uptake
nho_uptake
On average, 32% lower
On average, 11% lower
0
10
20
30
40
50
0 50 100 150 200 250Segment
Eo
F T
N (l
bs/a
c/y
r)hom_eof
nho_eof
Preliminary observations:
• New results promising
• Majority of EoF loadings within reasonable range of targets
• Plant N uptake within the range of observed data
• Further refinement needed
