Does nitrogen and phosphorus limitation impact methane oxidation, and can we measure that from

space?

Natalie N. Kashi

PhD studentUniversity of New

Hampshire

Impact Permafrost ??

http://www.noaanews.noaa.gov/stories2015/noaa‐analysis‐journal‐science‐no‐slowdown‐in‐global‐warming‐

in‐recent‐years.html

Permafrost

http://www.johnshawphoto.com/permafrost/

Permafrost

Wik, M., R. K. Varner, K. W. Anthony, S. MacIntyre, and D. Bastviken. "Climate-sensitive northern lakes and ponds are critical components of methane release."

Nature Geoscience (2016).

28 % of permafrost areas are peatlands

~277 Pg of soil organic carbon stored in permafrost peatland soils

Peatland Ecology Accumulate large quantities of organic matter in the soil profile

Imbalance between net primary production and decomposition

Photo Credit:  K. Wieder

3 % land surfaces, 1/3 of the world’s terrestrial soil carbon 90 % of peatlands are found in the northern ecosystems

Gore, A.J.P. (1983) Ecosystems of the World 4A: Mires, Swamp, Bog, Fen and Moor: General Studies. Elsevier

Peatlands – Global Significance

UAV Image Credit: M. Palace, C. Herrick, c.herrick@unh.edu;

Abisko, Sweden

Discontinuous Permafrost

Stordalen Mire, Sweden100 miles north of the Arctic circle

Permafrost Disturbance

HydrologyPermafrost

Thaw VegetationGreenhouse

Gas Emission

CH4 has 25 x greater global warming potential than CO2

Understand mechanism -> predict global warming scenarios

Methane (CH4) anaerobically produced by microbes

Decomposition of Organic

Matter

CH4 + 2H2O

CO2 + 4H2 acetateRoot exudates

CH3COOH CH4 + CO2

CH4CH4

WATER TABLETEMPERATUREVEGETATION

NPP

Methane Emissions and Oxidation

Methane Emissions and Oxidation

www.uvm.edu

Net CH4 Emissions = CH4 Production – CH4 Oxidation

Methane Emissions and Oxidation

CH4

CH4CH4

CO2 Carbon re-fixation CO2

CH4

CH4

10 - 30%

Palsa Carexfen

SphagnumLawn

3 PermafrostThaw Stages

10 PermafrostThaw Stages

Malhotra and Roulet 2015

Controls on CO2 & CH4 :

• water table depth • thaw depth • temperature • photosynthetically

active radiation• vascular green area

2015 Field Research

Christensen et al. 2004

Permafrost Disturbance

Nitrogen: Phosphorus: PotassiumN:P:K

Key Nutrients

Nitrogen:

ChlorophyllAmino acids, proteins,

DNA Rapid growth

Phosphorus:

Structure of Nucleic acidCell division

New plant tissueEnergy transformations

T01

T10

T03

T04T07

T05T08

T02

T06

T09

UAV Image Credit: M. Palace, C. Herrick, c.herrick@unh.edu; Photo Credits: Eric Heim

Stordalen PeatlandPermafrost Thaw Stages

T01- T10

CH4 Flux

CH4 Flux

CH4 Flux

CH4Flux

CH4 Flux

Stordalen Transitional Thaw Stages CH4 Flux 

Malhotra, A., and N. T. Roulet. 2015. Environmental correlates ofpeatland carbon fluxes in a thawing landscape: do transitionalthaw stages matter? Biogeosciences 12:3119–3130.

What are the CH4 Oxidation rates across this thaw

stage?

Do nutrients control CH4Oxidation?

2015 Permafrost- Methane Oxidation Research

2015 Permafrost- Methane Oxidation Research

AAB

DD

DD

D

D

BC

CD

Potential CH4 Oxidation in Transitional Permafrost Thaw Stages

Stage P < 0.0001Surface or Depth P = 0.9654Stage X Surface or Depth p = 0.3336

Phosphorus Concentrations in Transitional Permafrost Thaw Stages

A

A"

A"

D"

BC"

BC"

C"

BC"BC" BC"

AB

Stage p < 0.0001Surface or Depth p = 0.1680Stage X Surface or Depth p = 0.9552

Stordalen Transitional Thaw Stages CH4 Flux 

Phosphorus and Potential CH4 Oxidation

R2 = 0.42

Permafrost- Methane Oxidation- Nutrients

Total Nitrogen (mg/g)

R2 = 0.31

Nitrogen and Potential CH4 Oxidation

Permafrost- Methane Oxidation- Nutrients

%N  %P

Methane

 Oxidatio

n 

Methane

 Oxidatio

n 

early July mid July late July early July mid July late JulyPhosphorus and Potential CH4 OxidationNitrogen and Potential CH4 Oxidation

Phosphorus and Potential CH4 Oxidation

Permafrost- Methane Oxidation- Nutrients

Nitrogen and Potential CH4 Oxidation

%N  %P

Methane

 Oxidatio

n 

Methane

 Oxidatio

n 

Permafrost- Methane Oxidation- Nutrients

BCCBC

A:C

A:C

A:C

AA

AB

A:C

CDB:D

D

CD

A:D

CD

A

A:C

AB

A:C

Aerobic

Anaerobic

Aerobic

Anaerobic

35

30

25

20

15

10

5

0

N: P

Nitrogen and Phosphorus Ratios Along Permafrost Thaw Transition Stages

T01

T10

T03

T04T07

T05T08T02

T06

T09

UAV Image Credit: M. Palace, C. Herrick, c.herrick@unh.edu; Photo Credits: Eric Heim

Stordalen PeatlandPermafrost Thaw Stages T01- T10

CH4Flux CH4

Oxidation

CH4Oxidation

CH4Flux

CH4 FluxCH4Oxidation

CH4Flux

CH4Oxidation

CH4Flux

CH4Oxidation

Macrosystems and IsogenieResearch

Dr. Ruth Varner et al.

Scaling methane emissions using remote sensing

Varner 2016, unpublished data

Classification

LegendWet

Tall Shrub

Tall Gram

Semi-wet

Rock

Other

Hummock

Water Varner 2016, unpublished data

Varner 2016, unpublished data

Total methane production belowground

The next step…..

Refine methane emission scaling using nitrogen and phosphorus limitation by 

remote sensing

Guo et al. 2013 

• Existing Hyperion images at 30 meter resolution

• UAV drone with hyperspectral to get 1 cm accuracy

The next step…..

Can we identify nitrogen and phosphorus limitation from space?

Use nutrient limitation as a fingerprint to redefine plant communities by functional guilds

Relate biogeochemical processes to seasonal emissions 

Refine emission predictions across landscape

Use to continuously monitor emissions

Thank You!

Advisor: Dr. Ruth Varner

Committee members: Dr. Jill Bubier, Dr. Steve Frolking, Dr. Tom Lee, Dr. Wilfred Wollheim

REU Mentees: Erin Merik and Clarice PerrymanFellow lab members and NRESS studentsCollaborator: Dr. Reiner Geisler, Dr. Micheal Palace

Funding: NH Space Grant FellowshipEarth Science Department TA FellowshipNERU NSF REU ProgramHubbard Endowment for instrumentation purchase

Conclusions

Questions ?

If Nutrient limitations correlate with methane emissions, can we scale emissions along a permafrost thaw gradient?

Can we identify nitrogen and phosphorus limitation from space?

How will hyperspectral help us link scale hyper to scale across landscape, refine and specific with oxidation 

Conclusion any n and p with production or oxidation

Hyperion sensor‐ decomission?Operational and task again in fall Partially squares regressionAsd spectra

Permafrost Disturbance

Palsa Carexfen

SphagnumLawn

Surface (0-5) cmDepth (5-10) cm

Peat Cores in Glass Jars

Incubate with CH4,Rate of CH4 uptake

Measured:

• Potential CH4 oxidation rates• Peat nutrient analysis

(Nitrogen, Phosphorus, Carbon, Sulfur, Iron, Magnesium)• Enzymatic activities for Carbon, Nitrogen, and Phosphorus

• Stable Isotopes Nitrogen and Carbon

2015 Field Research

2015 Field Research

Phosphorus vs. 15N

R2 = 0.50

Phosphorus Concentrations in Transitional Permafrost Thaw Stages

A

A"

A"

D"

BC"

BC"

C"

BC"BC" BC"

AB

Stage p < 0.0001Surface or Depth p = 0.1680Stage X Surface or Depth p = 0.9552

Permafrost Thaw - Hypothesis 2

Phosphorus vs. 15N

R2 = 0.50

Tfaily, Malak M., William T. Cooper, Joel E. Kostka, Patrick R. Chanton, Christopher W. Schadt, Paul J. Hanson, Colleen M. Iversen, and Jeffrey P. Chanton. "Organic matter transformation in the peat column at Marcell Experimental Forest: Humification and vertical stratification." Journal of Geophysical Research: Biogeosciences 119, no. 4 (2014): 661-675.

Are nutrients from deeper peat a nutrient acquisition source?

0-15 cm peat

depth

Methanogensis

https://en.wikipedia.org/wiki/Palsa