suny-esf kikang bae (kbae02@syr)

SUNY-ESFKikang Bae

(kbae02@syr.edu)

Still waiting for fertilization effects on soil respiration and root respiration

Introduction

• Soil respiration is a major flux of carbon to the atmosphere.

• Nutrient additions to forest soils can af-fect soil respiration.

The global carbon cyclehttp://sitemaker.umich.edu/section2group4/the_link__human_influences_on_storm_intensity

Introduction

Ways nutrient addi-tion affects soil respi-ration:

Altering root activity Altering microbial activ-

ity Change above- and be-

low- ground carbon production

Soil respiration will in-crease or decrease af-ter nutrient addition?

soil respira-tion

aboveground respiration

photosynthesis

root + microbial respiration

CO2

CO2

CO2

CO2

Objectives

• To determine effects of nutrient additions on soil respiration and root respiration be-tween forest ages

• To understand which component (root or microbial) causes changing soil respira-tion, if there is a change at all

• To know which nutrients (N, P, N+P) have the greatest effect on soil respiration in our stands.

Hypothesis

Adding nutrients (N, P, N+P)

Soil respiration(root/microbial respiration)

An

nu

al soil r

esp

irati

on

(g

C/m

2)

Mid Old0

100

200

300

400

500

600

700

800

900

1000 Series1Series3Series5

Bartlett Hubbard BrookJeffers Brook

Age: P = 0.11Site: P = 0.02

Hypothesis

Adding nutrients (N, P, N+P)

Soil respiration(root/microbial respiration)

Soil respira-tion before fertilization(09’-11’)

Hypothesis

Adding nutrients (N, P, N+P)

Soil respiration(root/microbial respiration)

Soil respiration more Young: N+P > N > P >

ControlOld: N+P > P > N > Control

Middle (30~40 yrs)

Old (77~127 yrs)

Study sites

• Bartlett Experimental Forest (BEF)• Hubbard Brook (HB, WS 101)• Jeffers Brook (JB)

Young (20~22 yrs)Bartlett• C1• C2• C3

Bartlett• C4• C5• C6Jeffers Brook• MidHubbard Brook• Mid

Bartlett• C7• C8• C9Jeffers Brook• OldHubbard Brook• Old

Inten-sivetrench-ing

Methods

• Soil respiration: Chamber (Licor 8100).• Root respiration (Soil respiration – without live root respiration): Trenching

Results (Fertilization on soil respira-tion)

6/1/

2009

10/1

/200

9

2/1/

2010

6/1/

2010

10/1

/201

0

2/1/

2011

6/1/

2011

10/1

/201

1

2/1/

2012

6/1/

2012

0

2

4

6

8

BEF mid (C6)

So

il r

esp

ira

tio

n (

um

ol/

m2

/se

c)

6/1/

2009

8/1/

2009

10/1

/200

9

12/1

/200

9

2/1/

2010

4/1/

2010

6/1/

2010

8/1/

2010

10/1

/201

0

12/1

/201

0

2/1/

2011

4/1/

2011

6/1/

2011

8/1/

2011

10/1

/201

1

12/1

/201

1

2/1/

2012

4/1/

2012

6/1/

2012

0

2

4

6

8

10

12

BEF old (C9)

N+PNPC

Fertilization start

Fertilization start

P < 0.001

0

2

4

6

8

HB midS

oil

re

sp

ira

tio

n (

um

ol/

m2

/se

c)

6/1/

2009

10/1

/200

9

2/1/

2010

6/1/

2010

10/1

/201

0

2/1/

2011

6/1/

2011

10/1

/201

1

2/1/

2012

6/1/

2012

0

2

4

6 JB mid

So

il r

esp

ira

tio

n (

um

ol/

m2

/se

c)

6/1/

2009

8/1/

2009

10/1

/200

9

12/1

/200

9

2/1/

2010

4/1/

2010

6/1/

2010

8/1/

2010

10/1

/201

0

12/1

/201

0

2/1/

2011

4/1/

2011

6/1/

2011

8/1/

2011

10/1

/201

1

12/1

/201

1

2/1/

2012

4/1/

2012

6/1/

2012

0

2

4

6

8 JB old

0

2

4

6

8

HB old N+PNPC

Fertilization start

Fertilization start

Fertilization start

Fertilization start

P = 0.006

0

2

4

6

8

10

BEF young (C1)S

oil

re

sp

ira

tio

n

(um

ol/

m2

/se

c)

0

2

4

6

8

BEF young (C2)

N+PNPC

5/1/

2010

7/1/

2010

9/1/

2010

11/1

/201

0

1/1/

2011

3/1/

2011

5/1/

2011

7/1/

2011

9/1/

2011

11/1

/201

1

1/1/

2012

3/1/

2012

5/1/

2012

7/1/

2012

0

2

4

6

8

10 BEF mid (C4)

So

il r

esp

ira

tio

n (

um

ol/

m2

/se

c)

6/1/

2010

8/1/

2010

10/1

/201

0

12/1

/201

0

2/1/

2011

4/1/

2011

6/1/

2011

8/1/

2011

10/1

/201

1

12/1

/201

1

2/1/

2012

4/1/

2012

6/1/

2012

0

2

4

6

8

10

12

14 BEF old (C7)

Fertilization start

Fertilization start

Fertilization start

Fertilization start

BEF young (C2)

BEF mid (C6) BEF old (C7) JB mid JB old0

10

20

30

40

50

60

70

80

90

100

3733

49

44

53

46

39

47

41

4844

55

3740

4344 44

49

5458

N+P N P CR

oo

t co

ntr

ibu

tio

n (

%)

Results (Root contribution on soil respira-tion)

Soil respira-tion – without live root respi-ration

Results (Fertilization on trenching)

Jun 10'

Aug 10'

May 11'

Jun 11'

early Jul 11'

late Jul 11'

Aug 11'

Sep 11'

May 12'

Jun 12'

0

2

4

6

8

JB mid

So

il r

esp

ira

tio

n (

um

ol/

m2

/se

c)

Jun 10'

Aug 10'

May 11'

Jun 11'

early Jul 11'

late Jul 11'

Aug 11'

Sep 11'

May 12'

Jun 12'

0

2

4

6

8

JB old

N+PN PC

Fertilization start

Fertilization start

Jun

10'

Aug 1

0'

May 1

1'

Jun

11'

early

Jul 1

1'

late

Jul 1

1'

Aug 1

1'

Sep

11'

Oct 1

1'

May 1

2'

Jun

12'

0

2

4

6

8

BEF young (C2)S

oil

re

sp

ira

tio

n (

um

ol/

m2

/se

c)

Jun 10'

Aug 10'

May 11'

Jun 11'

early Jul 11'

late Jul 11'

Aug 11'

Sep 11'

Oct 11'

May 12'

Jun 12'

0

2

4

6

8

BEF mid (C6)

N+PN PC

Jun

10'

Aug 1

0'

May 1

1'

Jun

11'

early

Jul 1

1'

late

Jul 1

1'

Aug 1

1'

Sep

11'

Oct 1

1'

May 1

2'

Jun

12'

0

2

4

6

8 BEF old (C7)

So

il r

esp

ira

tio

n (

um

ol/

m2

/se

c)

Fertilization start

Fertilization start

Fertilization start

Summary

Adding nutrients (N, P, N+P)

Soil respiration No change (except C9 and HB mid)

Root respiration No change

Soil respiration No change Regardless of nutrients (N, P, N+P) and forest age

Conclusion

• There was little evidence of fertiliza-tion effects on soil respiration after 2 years nutrient addition.

Future plans

http://wric.ucdavis.edu/yst/images/none/nc5.JPG

May June

• Keep measuring soil respiration. • How do N, P, and N+P additions affect

root growth?

Acknowledge

Tim FaheyRuth Yanai

Melany Fisk

Acknowledge

Thank you...kbae02@syr.edu