Do ecosystem services have a biological cost? Ozone and climate regulation by Norway spruce forests along

an Alpine altitudinal transect in Trentino, northern Italy

Elena Gottardini, Fabiana Cristofolini, Antonella CristoforiResearch and Innovation Centre, Fondazione Edmund Mach (FEM)

San Michele all'Adige, Trento, Italy

Marco FerrettiTerraData environmetrics

Monterotondo M.mo, Grosseto, Italy

Scheme of the presentation

• Introduction– Ozone and impact on ecosystem services

provided by forests• The study on Picea abies along an

altitudinal transect on Alps– Study design– Measurements of environmental and tree

response variables • Results

– Environmental variables– Ozone removal– Relationship between ozone removal and

(i) structural/environmental variables(ii) tree responses

• Discussion– Functional interpretation of monitoring data – Possible biological costs of removing ozone

Ecosystem services

• Cultural• Provisioning• Supporting • Regulating

• Slope stability• Water cycle regulation• Carbon storage• Climate regulation• Air pollutant removal

Introduction

Ecosystem servicesbenefits people obtain from

ecosystems

Regulating servicesof forests

Mills et al., 2013

Ecosystem services

• Cultural• Provisioning• Supporting • Regulating

• Slope stability• Water cycle regulation• Carbon storage• Climate regulation• Air pollutant removal

Introduction

Ecosystem servicesbenefits people obtain from

ecosystems

Regulating servicesof forests

Mills et al., 2013

• Ozone can potentially affect the vegetation:- phytotoxicity - high values- wide distribution in remote areas

• Forests may reduce ozone through stomatal and non-stomatal deposition

Stomatal uptake

Surface reaction

depositionO3

Aim of the study is to assess the size of ozone regulating services provided by forests:

i) the portion of ozone removed by vegetationii) if ozone removal may have a biological cost for plants

with vegetation

without vegetation

20%

grad

ient

Scheme of the presentation

• Introduction– Ozone and impact on ecosystem services

provided by forests• The study on Picea abies along an

altitudinal transect on Alps– Study design– Measurements of environmental and tree

response variables • Results

– Environmental variables– Ozone removal– Relationship between ozone removal and

(i) structural/environmental variables(ii) tree responses

• Discussion– Functional interpretation of monitoring data – Possible biological costs of removing ozone

Fully randomized study on Norway spruce along an altitudinal gradient(900 - 1600 m a.s.l.) in Trentino, north Italy

Study design

Picea abies L.

0 20000 40000 60000

0-300

>300-600

>600-900

>900-1200

>1200-1500

>1500-1800

>1800-2100

>2100

elev

atio

n, m

a.s

.l.

ha

Fully randomized study on Norway spruce along an altitudinal gradient(900 - 1600 m a.s.l.) in Trentino, north Italy

Study design

Picea abies L.

0 20000 40000 60000

0-300

>300-600

>600-900

>900-1200

>1200-1500

>1500-1800

>1800-2100

>2100

elev

atio

n, m

a.s

.l.

ha

Statistical selection of:- 3 + 1 sites (open area)- 3 x 3 plot (forest)

750 m asl

900 m asl

1200 m asl

1600 m asl

Study design

open area

forest plot

Site 1

Site 2

Site 3

Environmental variables

In each forest plot and open area, measurement at 2 m of:

Passive sampling:- Ozone - Nitrogen dioxide

Data logger:- Temperature- Relative humidity

Period: May - August 2013

Tree response variables

• Chl a fluorescence (n=9 trees, 15 shoots per tree, C0 and C1)Fv/Fm = maximum quantum yield efficiency

• Crown condition (n=27 trees)

• Needle weight (n=9 trees, 900 needles per tree, C0)

• Shoot length (n=9 trees, 45 shoots per tree, C0)

Tree health

Productivity

Photosynthetic efficiency

Picea abies L.

Scheme of the presentation

• Introduction– Ozone and impact on ecosystem services

provided by forests• The study on Picea abies along an

altitudinal transect on Alps– Study design– Measurements of environmental and tree

response variables • Results

– Environmental variables– Ozone removal– Relationship between ozone removal and

(i) structural/environmental variables(ii) tree responses

• Discussion– Functional interpretation of monitoring data – Possible biological costs of removing ozone

Altitudinal profile of T and RH concentration

600

800

1000

1200

1400

1600

0 10 20

Temperature, °C

elev

atio

n, m

a.s

.l.

open areasforests

600

800

1000

1200

1400

1600

0 50 100

Relative humidity, %

elev

atio

n, m

a.s

.l.open areasforests

600

800

1000

1200

1400

1600

0 2 4 6NO2, g m-3

elev

atio

n, m

a.s

.l.

open areasforests

Altitudinal profile of NO2 concentration

• Nitrogen dioxide concentration decreased with altitude, both inside and outside forests.

• Concentrations are very low (1.4 ug m-3)

600

800

1000

1200

1400

1600

40 50 60 70 80 90 100O3, g m-3

elev

atio

n, m

a.s

.l.

open areasforests

Altitudinal profile of ozone concentration

• Ozone concentration increased with altitude, both inside and outside forests.

• Lower ozone concentrations within the forest (64.8 ug m-3) than in open areas (74.5 ug m-3) (P<0.001)

Site 0

Site 1

Site 2

Site 3

010002000300040005000

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Week

AOT4

0, p

pbh

0

20

40

60

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Week

O3,

ppb

AOT40 estimation

Weekly O3 concentration Weekly AOT40

AOT40 = [O3] x 75.484 – 2462.9

Site 1 - 913 m a.s.l.

0

1000

2000

3000

4000

5000

6000

7000

22/5 5/6 19/6 3/7 17/7 31/7

AO

T40,

ppb

h

AOT40: differences between open areas and forest

UNECE Critical level

Site 3 - 1521 m a.s.l.

0

1000

2000

3000

4000

5000

6000

7000

22/5 5/6 19/6 3/7 17/7 31/7

AO

T40,

ppb

h

Site 2 - 1177 m a.s.l.

01000200030004000500060007000

22/5 5/6 19/6 3/7 17/7 31/7

AO

T40,

ppb

h

0

1000

2000

3000

4000

5000

6000

7000

22/5 5/6 19/6 3/7 17/7

AO

T40,

ppb

h

open areaforest

Mean site 1, 2, 3

0

1000

2000

3000

4000

5000

6000

7000

22/5 5/6 19/6 3/7 17/7

AO

T40,

ppb

h

open areaforest

Site 1 - 913 m a.s.l.

0

1000

2000

3000

4000

5000

6000

7000

22/5 5/6 19/6 3/7 17/7 31/7

AO

T40,

ppb

h

AOT40: differences between open areas and forest

UNECE Critical level

Site 3 - 1521 m a.s.l.

0

1000

2000

3000

4000

5000

6000

7000

22/5 5/6 19/6 3/7 17/7 31/7

AO

T40,

ppb

h

Site 2 - 1177 m a.s.l.

01000200030004000500060007000

22/5 5/6 19/6 3/7 17/7 31/7

AO

T40,

ppb

h

Mean portion of ozone removed by forest 56%

Mean site 1, 2, 3

• Is there a relationship between ozone removal and environmental/structural factors?

– Elevation

– Ozone concentration

– LAI

– Tree circumference

Ozone removal vs. environmental/structural factors

0

2000

4000

6000

0 500 1000 1500 2000

Elevation, m a.s.l.

O3 r

emov

al, p

pbh

0

2000

4000

6000

50 60 70 80 90[O3], ug m-3

O3 r

emov

al, p

pbh

0

2000

4000

6000

50 100 150Tree circumference, cm

O3 r

emov

al, p

pbhy = -1528.8x + 10789

R2 = 0.72

0

2000

4000

6000

2 4 6 8LAI

O3 r

emov

al, p

pbh

P<0.05

• Is there a biological “cost” for plants because of ozone removal?

Response indicators:

– Trasparency

– Shoot lenght, needle wheight

– Chlorophyll fluorescence

Ozone removal vs. tree responses

0

3

6

9

12

0 2000 4000 6000Ozone removal, ppbh

Sho

ot le

nght

, cm

0

2

4

6

8

0 2000 4000 6000Ozone removal, ppbh

Nee

dle

wei

ght,

mg

0.80

0.82

0.84

0.86

0.88

0 2000 4000 6000Ozone removal, ppbh

Fv/F

m

0

10

20

30

40

50

0 2000 4000 6000Ozone removal, ppbh

Tran

spar

ency

, %

~ 900 m a.s.l.~1200 m a.s.l.~1500 m a.s.l.

Elevation vs. tree responses

y = 0.02x - 20.93R2 = 0.47

0

10

20

30

40

50

0 500 1000 1500 2000Elevation, m a.s.l.

Tran

spar

ency

, %

~ 900 m a.s.l.~1200 m a.s.l.~1500 m a.s.l.

y = -0.0048x + 13.87R2 = 0.98

0

3

6

9

12

0 500 1000 1500 2000Elevation, m a.s.l.

Shoo

t len

ght,

cmy = -0.00x + 7.39

R2 = 0.99

0

2

4

6

8

0 500 1000 1500 2000Elevation, m a.s.l.

Nee

dle

wei

ght,

mg

y = -0.00x + 0.88R2 = 0.97

0.80

0.82

0.84

0.86

0.88

0 500 1000 1500 2000Elevation, m a.s.l.

Fv/F

m

Relationship among tree responses

Nested within such a superimposed effect of the

elevation, the various response indicators were

related to each other

y = -0.00x + 0.85R2 = 0.90

0.810.82

0.830.84

0.850.86

0 10 20 30 40Transparency, %

Fv/F

m

y = 0.01x + 0.78R2 = 0.73

0.81

0.820.83

0.840.85

0.86

0 3 6 9 12Shoot lenght, cm

Fv/F

m

y = -0.10x + 9.34R2 = 0.80

0

3

6

9

12

0 10 20 30 40Transparency, %

Sho

ot le

nght

, cm

~ 900 m a.s.l.~1200 m a.s.l.~1500 m a.s.l.

Scheme of the presentation

• Introduction– Ozone and impact on ecosystem services

provided by forests• The study on Picea abies along an

altitudinal transect on Alps– Study design– Measurements of environmental and tree

response variables • Results

– Environmental variables– Ozone removal– Relationship between ozone removal and

(i) structural/environmental variables(ii) tree responses

• Discussion– Functional interpretation of monitoring data – Possible biological costs of removing ozone

Higher elevation > increase of abiotic stress(climate, solar radiation, ozone)

Lower photosyntheticefficiency

Greater susceptibility to other stress

Growth decrease

Worse crownconditions

More biotic andabiotic damages

Functional interpretation of monitoring data

Higher elevation > increase of abiotic stress(climate, solar radiation, ozone)

Lower photosyntheticefficiency

Greater susceptibility to other stress

Growth decrease

Worse crownconditions

More biotic andabiotic damages

Functional interpretation of monitoring data

Higher elevation > increase of abiotic stress(climate, solar radiation, ozone)

Lower photosyntheticefficiency

Greater susceptibility to other stress

Growth decrease

Worse crownconditions

More biotic andabiotic damages

Functional interpretation of monitoring data

• Vegetation provides ecosystem services → ozone removal

• Ozone removal resulted:

– slightly dependent on elevation and on ozone concentration

– slightly associated to lower productivity and photosynthetic activity, and higher crown transparency

• Thus, ozone removal seems to have a slight (if any) “biological cost”

• Plants are able to play an important role in regulating services -like ozone removal - also where environmental conditions are more stressful

• Side findings: data suggest a possible functional interpretation of forest health monitoring data

Possible biological costs of removing ozone

Acknowledgments

Forest and Fauna Serviceof Autonomous Province of Trento

Parco Naturale Paneveggio, Pale di San Martino