ghg presentation 2 [autosaved]

Greenhouse Gas Emissions Following Seasonal Flooding of Southeast Asian Tropical River Deltas

Amy Salvador[2] Michael Schaefer[1] Kate Roberts[1] Marco Keiluweit[1] Sam Ying[2] Scott Fendorf[1]

August 13th 2015

[1] Stanford University [2]University of California, Riverside

Global Scale Soil Carbon & Nitrogen

Global Scale Soil Carbon & Nitrogen

?

Why is this important?

CO2

CH4N2O

Why is this important?

CO2

CH4N2O

How much C & N from flooded soil?

Overarching Goal

• Be able to project the contribution of natural and anthropic flooding to Greenhouse gases

Soil

Biosphere

Soil

BiosphereRespiration &

Photosynthesis

CO2

SugarsO2

Microbes

Plants

Soil

Terrestrial

Soil

Terrestrial

INPUT OUTP

UT

Soil

Hydrosphere

Weathering

Carbon

Carbon

Carbon

Global Scale Soil Moisture

Illustration courtesy European Space Agency. image © ESA

Why in the Mekong Delta?Wet Season Dry Season

Research Question

What are the effects of flooding of soil on greenhouse gas emissions?

Hypothesis

When soil moisture is high, methane concentration is high and carbon dioxide concentration as well as nitrous oxide is low.

Field Sampling Lysimeter

Field Sampling Lysimeter

Porous

Field Sampling

H2O

H2O

H2O

H2O

H2O

H2O

Lysimeter

Other Elements (Ions)

Other Elements (Ions)

Field Sampling Lysimeter

Licor Cores with Rhizon Samplers

Soil Core

Laboratory Methods

Cores with Rhizon Samplers

Laboratory Methods

LicorSoil Core

Laboratory Methods

Soil CoreLicor Cores with

Rhizon Samplers

CO2 Exchange in Dry Conditions

O2

CO2 Exchange in Dry Conditions

O2

CO2 Exchange in Dry ConditionsCO2

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

Flux

CO2

Drying

Results of Flooding Conditions

O2

Results of Flooding Conditions

O2

Results of Flooding Conditions

Carbon

+

O2

Results of Flooding ConditionsCO2

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

Small CO2 Peak

May 10 – 24,2015

Flooding Event

CO2

Results of Flooding Conditions

H2

O

Results of Flooding Conditions

H2

OCarbo

n+

CO2

CO2 Exchange in Flooded Conditions

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

Small CO2 Peak

May 10 – 24,2015

Flooding Event

CO2

O2

CO2 Exchange in Dry ConditionsCO2

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

CO2 Flux

May 10 – 24,2015

Flooding Event

CO2

O2

CH4 Exchange in Flooded Conditions

CH4 Exchange in Flooded Conditions

Carbon

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

Flux

CH4 Exchange in Flooded Conditions CH4Flooding Event

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

Flux

CH4

CO2

O2

Gas Exchange When Soil Dries

N2O Gas Exchange When Soil Dries

O2 Nitroge

n+

N2O Gas Exchange When Soil DriesN2O

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

Flux

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

Flux

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

Flooding Event

CH4

N2OCO2

Drying

{Zone

of

Biot

ic

Influ

ence

6/14/2

015 1

4:00

5/13/2

015 1

7:00

4/11/2

015 2

0:00

3/10/2

015 2

3:00

2/7/20

15 2:

00

1/6/20

15 5:

00

12/5/

2014

8:00

11/3/

2014

11:00

10/2/

2014

14:00

20253035404550556065

0

20

40

60

80

100

120

140

160

Water at Biotic Zone (Depth 7 cm)

Date 10/1/2014 – 6/1/2015

Soil

Moi

stur

e (%

)High Soil Moisture Decreasing Soil Moisture

6/14/2

015 1

4:00

5/10/2

015 4

:00

4/4/20

15 18

:00

2/28/2

015 8

:00

1/23/2

015 2

2:00

12/19

/2014

12:00

11/14

/2014

2:00

10/9/

2014

16:00

20253035404550556065

020406080100120140160

Water at Biotic Zone (Depth 7 cm)

Date 10/1/2014 – 6/1/2015

Soil

Moi

stur

e (%

)

NPO

C (m

g/L)

“O

rgan

ic

Carb

on”

High Soil Moisture Decreasing Soil Moisture

{

Zone

of

Biot

ic

Abse

nce

{Zone

of

Biot

ic

Influ

ence

{{Zo

ne o

f Bi

otic

In

fluen

ce

Zone

of

Biot

ic

Abse

nce

6/14/2

015 1

4:00

5/15/2

015 1

1:30

4/15/2

015 9

:00

3/16/2

015 6

:30

2/14/2

015 4

:00

1/15/2

015 1

:30

12/15

/2014

23:00

11/15

/2014

20:30

10/16

/2014

18:00

20

25

30

35

40

45

5055

Water Below Biotic Zone (Depth 21 cm)

Date 10/1/2014 – 6/1/2015

Soil

Moi

stur

e [%

]High Soil Moisture Decreasing Soil Moisture

20

25

30

35

40

45

50

55

0

10

20

30

40

50

60Water Below Biotic Zone (Depth 21 cm)

Date 10/1/2014 – 6/1/2015

Soil

Moi

stur

e (%

)

NPO

C (m

g/L)

“O

rgan

ic

Carb

on”

High Soil Moisture Decreasing Soil Moisture

O2

O2

C CC

CC

C

C

O2

C CC

CC

C

C

O2

Summary

Gas Emissions Available aqueous Carbon Soil Carbon availability

Summary

Gas Emissions Available aqueous Carbon Soil Carbon availability

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

Flux

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

Flux

5/10/15 5/12/15 5/14/15 5/16/15 5/18/15 5/20/15 5/22/15 5/24/15

CH4

N2OCO2

Flooding Event Drying

Summary

Gas EmissionsAvailable aqueous Carbon Soil Carbon availability

Summary

Gas Emissions Available aqueous CarbonSoil Carbon availability

My piece applied to larger goal

“Organic carbon oxidation rates, as measured by dissolved inorganic carbon (DIC) concentrations, further support arsenic liberation via near-surface anaerobic microbial respiration.”

Water Quality

Water Quality

Food Security

Water Quality

Food Security

Climate Change

Acknowledgements

Michael Schaefer Scott Fendorf Fendorf Lab Group Guangchao Li Doug Turner Samantha Ying Wakuna Galega Jerry Harris Tenea Nelson Lupe Carillo

Thank You