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AMMONIA AND WATER FLUXES MODELLING OVER

AGRICULTURAL PLOTS

Gianfranco Rana

CRA – Unità di ricerca per i Sistemi Colturali degli Ambienti caldo aridi, CRA – Unità di ricerca per i Sistemi Colturali degli Ambienti caldo aridi, BariBariINRA – Unité Mixte Recherche Environnement et Grandes Cultures, INRA – Unité Mixte Recherche Environnement et Grandes Cultures, GrignonGrignon, ,

FranceFrance

AMMONIA AND WATER FLUXES MODELLING OVER

AGRICULTURAL PLOTS

AMMONIA AND WATER FLUXES MODELLING OVER

AGRICULTURAL PLOTS

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Summary

• “FIDES 3D”– Transport model– The sources and the sinks of ammonia

• “Volt’air”– Mechanistic model– Ammonia volatilization

• Water fluxes– A review on the reference evapotranspiration

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Problems with NH3 sampling and flux measure

Tendence to make strong hydrogen link with H2O

Adsorbment and memory effect

Punctual sources, spatial variability

Time variability

Dispersion, possible minimum deposition

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NH3 volatilization from agricultural system

It dipends on (Sommer et al., 2003): NH4

+ concentration

Temperature, solar radiation, wind speed, rain, air humidity … Turbolent transport pH Evaporation rate, dew Soil type, soil moisture Application techniques

The process: NH3 transfert from nitrogen liquid solution to the air in contactN applied losses: Urea: 10-25%; Slurry: > 60%

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FIDES3D: Flux Interpretation by Dispersion and

Exchange over Short range in three Dimensions Loubet et al., 2001; Loubet et al., 2010

HypothesisHypothesis Advection-diffusion equation (Philip, 1959) Power laws for wind speed and vertical diffusivity profiles (Huang, 1979) No chimical reactions in atmosphere and surface

Inputs:Inputs:• Turbulence of atmosphere

• Concentration of NH3 at background and level z

• Fetch, geometrical properties of the source

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Superposing principleSuperposing principleIt relates the concentration of scalar in a point of the field to the source strength in another point (Raupach, 1989; Thompson, 1998)

Principles

sy

xCzyxC, xall

sssssss bgd

s

dx )z ,y , x| zy,D(x, )z ,y ,(S ),,(

Source strength in (xs, ys,zs): function of Rb(u*, B) e Cc

Dispersion Function

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Surface/air NH3 exchange

• The resistance analogy approach a stomatal pathway a cuticular pathway

b

czsssss R

CzyxCzyxS

,,,,

Ammonia has a canopy compensation point =concentration value for which the flux is zero

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Set-up

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Final considerations on FIDES3D

• the following input are needed: (1) the NH3 air concentration at least at one height above the

surface(2) the background concentration(3) the standard micrometeorological variables acquired usually by

a sonic anemometer(4) the dimension of the local source along the wind direction and

the fetch where the NH3 is measured • From the computational point of view

– the cuticular resistance Rw and the strength Ss are considered as unknown and they are inferred with a standard iterative method using the classical Netwon-Raphton technique

– once Rw and Ss are calculated the advection flux Fa of ammonia is estimated by a numerical integration of the advection-dispersion equation

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Volt’air (Génermont and Cellier, 1997)

Ammonia volatilization from the surfaceAmmonia volatilization from the surfaceVan der Molen et al. (1990)Van der Molen et al. (1990)

Transfer of ammonia from the surface toward the Transfer of ammonia from the surface toward the atmosphereatmosphere

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Starting hypothesis

Urea is converted to ammoniacal nitrogen and carbonate within a few hours after application

The simulation takes place for a short period (week), thus nitrogen transformations by organic matter mineralization, ammoniacal uptake by the plants, oxidation and/or nitrification are not taken into account for

The mineralization of the organic nitrogen from the slurry is considered to be negligible

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• The flux of ammonia is bidirectional and the source is not known a priori

• Model of local advection (Itier and Perrier, 1976)• Change in the surface flux as a function of the

distance from the leading edge in the wind direction (fetch) and the difference in the surface concentration for an abrupt change in the surface concentration

• The flux of ammonia is bidirectional and the source is not known a priori

• Model of local advection (Itier and Perrier, 1976)• Change in the surface flux as a function of the

distance from the leading edge in the wind direction (fetch) and the difference in the surface concentration for an abrupt change in the surface concentration

ib

NHia z

XkuaF

0

* 3.03

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Inputs: 1. general informationInputs: 1. general information

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Inputs: 2. agricultural practicesInputs: 2. agricultural practices

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Inputs: 3. soil hydraulic properties

Inputs: 3. soil hydraulic properties

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Inputs: 4. physical and chemical properties

Inputs: 4. physical and chemical properties

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Inputs: 5. SoilInputs: 5. Soil

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Inputs: 6. MeteorologyInputs: 6. Meteorology

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Landriano (45° 18‘; 9° 15' E) (Università di Milano)

Field ~ 4 ha bare soil

27-31 March 2009

Surface spreading of cow slurry, filling after 24 h

~184 kgN ha-1 ~93 kgN-NH4+ ha-1

Slurry spreadingSlurry spreading

15 cm

20

0

5

10

15

20

25

30

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26.03.200918:22

27.03.200909:30

28.03.200900:30

28.03.200915:30

29.03.200907:30

29.03.200922:30

30.03.200913:30

time

NH

3 fl

ux

1.45

m (m g

/m2s)

FIDES EDDY

NHNH3 3 Flux by FIDES3DFlux by FIDES3D

Soil filling

Start spreading

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Rutigliano (CRA-SCA Bari)

17-29 July 2008

Grain Sorghum (~ 2 ha)

Urea application: 30 kgN ha-1 (01/07/2008) 90 kgN ha-1 (16/07/2008) 120 kgN ha-1 (22/07/2008)

Irrigation by aspersion

Urea spreadingUrea spreading

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NH3 Flux by FIDES3DNH3 Flux by FIDES3D

0

1000

2000

3000

4000

5000

6000

22.07.200801:01

23.07.200805:01

24.07.200809:01

25.07.200813:01

26.07.200817:01

27.07.200821:01

29.07.200801:01

Date

NH

3 F

luxe

s (n

g/m

2s)

EC (1.3 m) Emiss FIDES F QC corrTF mia del 170111 (no phase shift) EC_corr Tfexp lim dx0.5

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Cumulate valuesCumulate values

0 48 96 144 192 240 288 336Hours after spreading

0

0.2

0.4

0.6

0.8

1N

orm

aliz

ed

NH

3 lo

sses

T-I: s lurryT-II: urea

last urea spreading andirrigation

slurry/urea spreading

slurryincorporation

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WATER FLUXES

Katerji, N., Rana, G., 2011. Crop reference evapotranspiration: a discussion of the concept, analysis of the process and validation. Water Resources Management, on line since 5 January 2011.

DOI 10.1007/s11269-010-9762-1

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Analisi teorica e fisica dellAnalisi teorica e fisica dell’’evaporazioneevaporazione

• Penman (1946): evaporazione da superficie di acqua libera

• Monteith (1963-1965): evapotraspirazione da una coltura teorica

• Thom (1975-1978): formalizzazione della resistenza aerodinamica

• Perrier (1975-1983): evapotraspirazione da una coltura reale

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Evaporazione potenziale (Penman)

ap

p

rDcAE

•Nessun controllo biologico da parte di una eventuale coltura•Nessun controllo dovuto alla struttura di una eventuale coltura•Può rappresentare bene la domanda evaporativa dell’atmosfera

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Evaporazione potenziale di una coltura (Perrier)

a

pcp

rr

EE

01

Una coltura con acqua sempre disponibile oppone solo una resistenza dovuta alla sua struttura

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pcp EE

Crop Height Climatic conditions

r0

Grass 0.1 Normal 0-5

Bean 0.4 Normal 5-10

Maize 0.6 Normal 10-15

Maize 2.2 Normal 20-30

Wheat 0.2 Weak demand 0

Wheat 0.4 Weak demand 6

Wheat 0.6 Weak demand 10

Wheat 0.2 Normal 5

Wheat 0.4 Normal 10

Wheat 0.6 Normal 20

-Situazione teorica-Solo dopo una pioggia o rugiadao irrigazione per aspersione-Le due quantità possono essere uguali per il prato in particolari condizioni

Evaporazione potenziale di una coltura (Perrier)

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Evapotraspirazione (Monteith)

a

c

p

sc

rr

EE

rrr

1

0

Se non vi è nessuna saturazione a nessun livello allora la coltura oppone una resistenza biologica: la resistenza colturale

Questa varia tra un minimo, quando la coltura è in buone condizioni idriche e un massimo quando è completamente secca

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Relazioneresistenza stomatica/resistenza colturale

Monteith et al. (1965)

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SintesiPenman -> Perrier -> Monteith

pcp EEE

-Situazione teorica-Solo dopo una pioggia o rugiada o irrigazione per aspersione-Le due quantità possono essere uguali per il prato in particolari condizioni

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, ρ, γ, cp quasi constanti

• A, energia disponibile = Rn-G

– Rn, radiazione netta

– G, flusso di calore nel suolo

• D, deficit di pressione di vapore

• ra, resistenza aerodinamica

• rc, resistenza colturale

ac

ap

rr

rDcAE

1

Modello di Penman-Monteith versione Perrier

Le misure dovrebbero esser fatte Le misure dovrebbero esser fatte SULLA COLTURASULLA COLTURA

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Prato di riferimento

• Ben irrigato• Ben concimato• 10 - 15 cm• Esteso • Solo una specie (lolium

perenne L.)

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Penman-Monteith FAO56

• ET0 calcolata sopra un prato di riferimento• Scala temporale

– Cn=37 e Cp=0.24– Cn=900 e Cp=0.34

2

2

0 1273

408.0

uC

DuT

CGR

ETp

nn

Resistenza colturale costanteResistenza colturale costante

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TomatoGrass

Soybean

Sunflower Sweet sorghum

Grain sorghum

Emod=0.61 Em+2.06 R2=0.55

Emod=0.80 Em+0.73 R2=0.77

Emod=0.92 Em+0.27 R2=0.40

Emod=0.98 Em R2=0.55

Emod=0.78 Em+0.30 R2=0.94

Emod=0.64 Em+1.69 R2=0.77

ET

FA

O 5

6 (m

m d

-1)

ET measured (mm d-1)0 4 8

0

4

8

0 4 8

0

4

8

0

4

8

FAO 56 DAILY SCALE

LA I>2

LA I<=2

TomatoGrass

Soybean

Sunflower Sweet sorghum

Grain sorghum

Emod=0.61 Em+2.06 R2=0.55

Emod=0.80 Em+0.73 R2=0.77

Emod=0.92 Em+0.27 R2=0.40

Emod=0.98 Em R2=0.55

Emod=0.78 Em+0.30 R2=0.94

Emod=0.64 Em+1.69 R2=0.77

ET

FA

O 5

6 (m

m d

-1)

ET measured (mm d-1)0 4 8

0

4

8

0 4 8

0

4

8

0

4

8

FAO 56 DAILY SCALE

LA I>2

LA I<=2

37

effc

c

sc

LAIr

LAIr

LAI

rr

1005.0

100

min,

rrcc=70 s/m=70 s/m

rrcc=50 s/m=50 s/m

Storia della resistenza colturale costante per un prato Allen et al., (1989; 1994; 1998; 2006)

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Monteith, J.L., 1965. Evaporation and the environment. XIXth Symposia of the Society for

Experimental Biology. In the State and Movement of Water in Living Organisms. University Press,

Swansea, Cambridge, pp. 205–234

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J. Appl. Ecology, 1965*Rothamsted, UK

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Pubblicazioni1. Katerji, N., Rana, G., Mastrorilli, M., 2010. Modelling of actual evapotranspiration in open top

chambre (OTC) at daily and seasonal scale: Multiannual validation on soybean in contrasted conditions of water stress and air ozone concentration. European Journal of Agronomy, 33, 218-230

2. Rana, G., Katerji, N., Ferrara, R., Martinelli, N., 2010. An operational model to estimate hourly and daily crop evapotranspiration in hilly terrain: validation on wheat and oat crops. Theoretical and Applied Climatology (on line, under press)

3. Katerji, N., Rana, G., Fahed, S., 2010. Parameterizing canopy resistance using mechanistic and semi-empirical estimates of hourly evapotranspiration: critical evaluation for irrigated crops in the Mediterranean. Hydrological Processes (on line, under press)

4. Loubet, B., Gènermont, S., Ferrara, R., Bedos, C., Decuq, C., Personne, E., Fanucci, O., Durand, B., Rana, G., Cellier, P., 2010. An inverse model to estimate ammonia emissions from fields. Eur. J. Soil Sci (on line, under press)

5. Katerji, N., Rana, G., 2011. Crop reference evapotranspiration: a discussion of the concept, analysis of the process and validation. Water Resources Management, (on line, under press).

6. R. M. Ferrara, B. Loubet, P. Di tommasi, T. Bertolini, V. Magliulo, P. Cellier, G. Rana. Evaluation of eddy covariance measurement of ammonia fluxes with a Quantum Cascade Tunable Infrared Laser Differential Absorption Spectrometer (QC-TILDAS) (in preparazione).

7. R. M. Ferrara, B. Loubet, P. D. Palumbo, V. Magliulo, G. Rana. Dynamic of ammonia volatilization over sorghum fertilized under Mediterranean conditions (in preparazione).

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