What Can Tea Bags in Salt Marshes Tell Us About Climate Change? Jim Tang, Ph.D. Marine Biological Laboratory in Woods Hole

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1 What Can Tea Bags in Salt Marshes Tell Us About Climate Change? Jim Tang, Ph.D. Marine Biological Laboratory in Woods Hole

2 Funding: Acknowledgements NOAA/National Estuarine Research Reserve System Science Collaborative (BWM1 and BWM2) Collaborators: Faming Wang, Kevin Kroeger, Omar Abdul-Aziz, Serena Moseman-Valtierra,, Meagan Gonneea, Kate Morkeski, Jordan Mora, Joanna Carey, Tonna-Marie Surgeon-Rogers, James Rassman, Chris Weidman

3 Global carbon cycling 2.4 Unit: Billion ton Pg ? IPCC, 2001 IPCC, 2001

4 Carbon-climate-ecosystems-Earth system Carbon cycle Concentration (ppm ) A tm ospheric C O 2 record from Mauna Loa Y ear T em perature ( o C) G lobal m ean tem perature anom aly (relative to m ean) Y ear Climate change: warming, sea level, storms Ecosystems Earth system processes and modeling

5 Coastal blue carbon Photosynthesis: 6CO 2 + 6H 2 O + light C 6 H 12 O 6 + 6O 2 Respiration: C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + heat Calcification: Ca HCO - 3 CaCO 3 + H 2 O + CO 2 Tang et al

6 Therefore, to understand and predict climate change, we need to understand the carbon cycle; to mitigate climate change, we need to increase carbon uptake (the negative carbon emissions), where coastal salt marsh plays an important role.

7 Negative Emissions Technologies (NET) Developing a Research Agenda for Carbon Dioxide Removal and Reliable Sequestration US NAS 2018, Negative Emissions Technologies

8 Carbon cycling components F(L) R CH 4 F(L) R CH 4 GPP C stocks N restore GPP C stocks Tang et al. Unpublished

9 In-situ GHG Chamber flux measurement for salt marsh CO 2 /CH 4 Analyzer

10 Flux measurement for Phragmites

11 Blue carbon monitoring system Weather system Fluorescence CO 2 & CH 4 Camera Yang, Tang, et al Geo. Res. Letter; Yang, Tang, et al. 2017, Global Change Biology; Lu at al Agri. For. Met.; Lu et al. 2018a,b, Remote Sensing

12 Long sediment cores Use 210 Pb to date sediment cores (Gonneea et al.)

13 Tea decomposition experiment: to understand the decomposition rate of organic carbon Djukic et al. 2018

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15 Djukic et al. 2018

16 Using Cameras to record leaf phenology Tang et al Ecosphere

17 Greenness Leaf phenology vs. carbon (i.e. GPP) Winter Spring Full canopy Summer Senescence Autumn Leaf Abscission GPP Phenology Quiescence Bud-break January April July Day of the year October Courtesy of Jeremy Fisher

18 CO 2 and CH 4 fluxes in the pristine site (gc m -2 y -1 ) R(394) F(L) (215) CH 4 (4) GPP (773) NECB (160) C stocks Flux ( mol m -2 s -1 ) Flux (nmol m -2 s -1 ) NEP GPP R CH Tang et al. unpublished DOY

19 Case study: Herring River wetland restoration project Natural Dike marsh Degraded marsh

20 CO 2 -equavalent CH 4 emission (g CO 2 -C m -1 yr -1 ) C Burial Rate (g C m -2 yr -1 ) Net CO 2 uptake C from different ecosystems Saltmarsh Phragmites Brackish Typha Marsh 9, CH 4 emissions Salt marsh: gc m -2 y -1 ) Saltmarsh Phragmites Brackish Typha Marsh Wang et al. in review

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22 Blue Carbon Credit Carbon credit = Carbon storage after human intervention - Carbon storage baseline

23 Conclusions We use gas analyzers, cameras, and tea bag experiments to understand the carbon cycle. We found that the coastal wetland is a significant carbon sink (blue carbon). Restoration increased carbon sequestration and decreased CH 4 fluxes.

24 Global carbon cycling 2.4 Unit: Billion ton Pg IPCC, 2001 IPCC, 2001