Departmentof

Plant Ecology

Ozone Risk Assessment for Winter Wheatat Local Scale:

Evaluation of the UNECE Flux Approach

Ludger Grünhage1), Harald Braden2), Jürgen Bender3),

Janina Wojtkowiak1), Hans-Joachim Weigel3), Klaus Hanewald4)

1) Department of Plant Ecology, Justus-Liebig University, Giessen

2) German Meteorological Service, Agrometeorological Research and Advisory

Station, Braunschweig

3) Institute of Biodiversity, Johann Heinrich von Thünen-Institute (vTI),

Federal Research Institute for Rural Areas, Forestry and Fisheries, Braunschweig

4) Hessian Agency for the Environment and Geology, Wiesbaden

Grünhage et al.

22nd TFM ofICP Vegetation

Ozone Risk Assessment for Winter Wheat at Local Scale:Evaluation of the UNECE Flux Approach

•••• Council Directive 96/62/EC Article 6 of 27 September 1996

•••• Council Directive 2002/3/EC of 12 February 2002

•••• Council Directive 2008/50/EC of 21 May 2008

→ air quality in the EU has to be assessed and managed

by means of sampling points for fixed measurement of

concentrations of the respective air pollutant

Grünhage et al.

22nd TFM ofICP Vegetation

Ozone Risk Assessment for Winter Wheat at Local Scale:Evaluation of the UNECE Flux Approach

•••• introduction

•••• flowchart of the risk evaluation procedure

•••• stomatal conductance model•••••••• work programme

•••• conversion of [O3] at zref to canopy height•••••••• work programme

•••• stomatal uptake calculations

•••• results

gflag leaf,stom,O3

Fflag leaf,stom

Fflag leaf,stom6

AFflag leaf,stom6

potential yield loss

risk evaluationlocal risk assessment- flowchart -

Mapping Manual(UNECE 2007)

cO3(zh)Fc(O3) = −cO3(zref)

Rtotal

Rca

no

py

, O

3

Rc,

O3

Rc, stom, O3

upsc

alin

g

stomatal conductance model

derived from open-top chamber experiments with "old" wheat cultivars

gflag leaf, stom, O3 = gflag leaf, stom, max, O3 · Jarvis-Stewart functions

���� gflag leaf, stom, max = 450 mmol O3 m−−−−2 PLA s−−−−1

initial registration: Astron 1989 Pegassos 1994

gflag leaf, stom, max

(Massman 1998; Grünhage & Haenel 1997, 2008: DO3/DH2O = 0.662)

Bender et al.(2009)

stomatal conductance model

derived from open-top chamber experiments with "old" wheat cultivars

gflag leaf, stom, O3 = gflag leaf, stom, max, O3 · Jarvis-Stewart functions

���� gflag leaf, stom, max = 450 mmol O3 m−−−−2 PLA s−−−−1

���� DO3/DH2O in air

���� Jarvis-Stewart function for phenology fphen

(cf. Massman 1998; Grünhage & Haenel 1997)

?

2

1

3 24

Environmental Monitoringand Climate Impact Research

Station Linden

http://www.uni-giessen.de/cms/ukl-en

winter wheat initial registration

(Germany)

1: Carenius 2006

2: Manager 2006

3: Opus 2003

4: Limes 2003

spring wheat (in Braunschweig)

Taifun 2003

•••• gstom, max for several winter and spring wheat cultivars

•••• parameterization of gstom

- Work Programme -

conversion of [O3] at zref to that at zh

���� Ratmosphere

���� Rquasi.laminar layer

���� Rcanopy

•••• Gc, stom

•••• Gc, non-stom

→ canopy development

(cf. Simpson et al. 2003)

(upscaled from gflag leaf, stom)

(cf.G

rünhag

e &H

aenel

2008)

•••• DOYstart 60

•••• DOYgrowth stage 31 stem elongation

•••• DOYgrowth stage 51 beginning of heading

•••• DOYgrowth stage 87 hard dough

•••• DOYharvest over ripe

winter wheat canopy development

- LAInon-senescent, LAIsenescent, h -

based on observed growth stages:

•••• DOYgrowth stage 39 flag leaf fully developed : DOYgrowth stage 51 −−−− 9

•••• DOYgrowth stage 61 beginning of anthesis : DOYgrowth stage 51 + 7

•••• DOYgrowth stage 65 mid anthesis : DOYgrowth stage 61 + 3

•••• DOYgrowth stage 75 medium milk : DOYgrowth stage 51 + 25

estimated entry date of growth stages:

AM

BA

Vag

rom

eteoro

logical

model

for estim

ation actu

alev

apotran

spiratio

n(G

erman

Meteo

rolo

gical

Serv

ice, Brau

nsch

weig

)

winter wheatcanopy development

LAInon-senescentLAIsenescent

canopy height

winter wheat

'Batis'

initial registration in Germany:1994

(2)

upscaling from leaf to canopy level

yields in an overestimation of Gc, stom

→ "higher" total ozone flux density Fc(O3)

→ "lower" ozone concentration at canopy top cO3(zh)

→ "lower" stomatal uptake Fflag leaf, stom

→ "lower" risk than in reality

•••• Gc, stom = gflag leaf, stom · LAInon-senescent

•••• Gc, stom = gflag leaf, stom · LAInon-senescent ·1

1 −−−− ββββ*sunlit

- sun-shade model of de Pury & Farquhar (1997)parameterized for wheat

- www.uni-giessen.de/cms/ukl-en/PLATIN

consideringradiation absorptionby the sunlit leaves

(1)

•••• upscaling of gstom from leaf to canopy level (Braunschweig)

•••• radiation and AMBAV canopy development model (Giessen, Braunschweig)

−−−− evapotranspiration

−−−− LAI and canopy height development

−−−− within canopy radiation distribution

- Work Programme -

canopy gasexchangechamber

Dr. Stefan Burkartvti, Institute of Agricultural

Climate Research

weighablebackfilledlysimeter

DWD, Braunschweig

soil water potential

stomatal uptake calculations

method 1: "real" atmospheric stratification

method 2: neutral atmospheric stratification

The estimation of stomatal flux of ozone (Fst) is based on the assumption that the concentration

of ozone at the top of the canopy represents a reasonable estimate of the concentration at the

upper surface of the laminar layer near the flag leaf. (Mapping Manual Revision, 31.08.2007)

Rflag leaf, laminar layer + Rflag leaf, total

Fflag leaf,stom = c(zh) · gflag leaf, stom ·Rflag leaf, total

1:1

The estimation of stomatal flux of ozone (Fst) is based on the assumption that the concentration

of ozone at the top of the canopy represents a reasonable estimate of the concentration at the

upper surface of the laminar layer near the flag leaf. (Mapping Manual Revision, 31.08.2007)

Rflag leaf, laminar layer + Rflag leaf, total

Fflag leaf,stom = c(zh) · gflag leaf, stom ·Rflag leaf, total

1:1

The estimation of stomatal flux of ozone (Fst) is based on the assumption that the concentration

of ozone at the top of the canopy represents a reasonable estimate of the concentration at the

upper surface of the laminar layer near the flag leaf. (Mapping Manual Revision, 31.08.2007)

Rflag leaf, laminar layer + Rflag leaf, total

Fflag leaf,stom = c(zh) · gflag leaf, stom ·Rflag leaf, total

1:1

results

Observed and estimated potential yield losses of winter wheat

risk evaluation for the monitoring station Linden

of the air quality monitoring network of Hesse

links to the monitoring network:

http://www.hlug.de or http://www.uni-giessen.de/cms/ukl-en

yield loss not likely

low probability for yield loss

increasing probability for yield loss

high probability for yield loss

Grünhage et al.

22nd TFM ofICP Vegetation

Ozone Risk Assessment for Winter Wheat at Local Scale:Evaluation of the UNECE Flux Approach

- conclusion -

���� In principle, the stomatal uptake (AFflag leaf, stom6) based riskevaluation for wheat can be applied successfully at local scale.

���� The approach presented here requires an appropriate upscalingprocedure from leaf to canopy level and based on parametersroutinely measured by the air quality monitoring networks.

unsolved problems/questions:

•••• gap filling procedure for the input parameters measured by the air quality

monitoring stations

•••• validation of stomatal conductance parameterization with "modern" wheat

cultivars

•••• upscaling procedure from leaf to canopy level

Thanks for your attention!