R1100 Permafrost Hydrology Schuur

Document Sample
R1100 Permafrost Hydrology Schuur Powered By Docstoc
					Permafrost/Hydrology
2009 LTER Symposium

      Ted Schuur
  University of Florida

   Merritt Turetsky
  University of Guelph

        Jay Jones
   University of Alaska
              State Factors
Climate         Humans              Time


             Ecosystem Dynamics

          Permafrost    Hydrology



Topography                   Organisms
              Parent material
        Presentation Overview
What is the effect of changes in permafrost and
 hydrologic regime on terrestrial and aquatic
 ecosystem dynamics?


1. Upland Thermokarst
   (Schuur; Eight Mile Lake/Healy)

2. Wetlands
   (Turetsky; APEX/Bonanza Creek Bluff)

3. Upland Streams
   (Jones; Caribou Poker Creek)
                  Schuur, E.A.G., J. Bockheim, J. Canadell, E.
                  Euskirchen, C.B. Field, S.V Goryachkin, S.
                  Hagemann, P. Kuhry, P. Lafleur, H. Lee, G.
                  Mazhitova, F. E. Nelson, A. Rinke, V. Romanovsky, N.
                  Shiklomanov, C. Tarnocai, S. Venevsky, J. G. Vogel,
                  S.A. Zimov. 2008. Vulnerability of permafrost
                  carbon to climate change: Implications for the
                  global carbon cycle. BioScience 58: 701-714.




Permafrost Thaw   Effects on Ecosystems/Hydrology
                              Global Carbon Pools
   Global Vegetation C                                                            650 Pg
   Global Soil C (1m)                                                             1500 Pg
   Atmosphere                                                                     777 Pg



   Permafrost Zone Soil C
       Peatlands (several m)                                                      277 Pg
       Mineral Soil (3m)                                                          747 Pg
       Siberian Deep C (~25m)                                                     407 Pg
       Alluvial Deep C (~25m)                                                     241 Pg
                                                                                  1672 Pg
[Jobaggy et al. 2000, Field et al. 2007, Zimov et al. 2006, Tarnocai, in press, Schuur et al. 2008]
The impact of permafrost thaw on old carbon release
           and net exchange from tundra
 Net Ecosystem Exchange

                          100

                          50
                                sink                       Minimal ≈ neutral
                                                           Moderate = sink
         (g C m-2)




                           0
                                                           (GPP, Reco)
                          -50                              Extensive = source
                     -100
                                               Minimal
                                                           (GPP, Reco)
                                               Moderate

                     -150 source
                                               Extensive
                                                                                    100




                                                                 Old Carbon Loss
                           2004         2005 2006                                          Minimal Thaw




                                                                   (g C m-2 yr-1)
                                                                                     90
                                   Calendar Year                                     80    Moderate Thaw
                                                                                     70    Extensive Thaw
                                                                                     60
                                                                                     50
                               Minimal = 66 g m-2 yr-1                               40
                                                                                     30
                               Moderate = 40%                                       20

                               Extensive = 78%
                                                                                     10
                                                                                      0
                                                                                          2004   2005       2006

[Schuur et al. in press, Vogel et al., in press]
                           Permafrost Carbon Pool

Permafrost Zone Soil C
    Gelisol Soil Order (3m)                  818 Pg
                                             x 9.4-12.9%
                                             77-106 Pg

     Permafrost C Loss                       (0.8-1.1 Pg/yr)
     Current Land Use Change                 (1.5±0.5
Pg/yr)
          Deep Permafrost C                  650 Pg
                                             x?
                                             ? Pg
[Schuur et al. in press]
Hydrologic Carbon Export
                      Annual Flux (g C m-2 yr-1)
                        Min     Mod     Ext
            DIC         1.9     0.9     1.6
            DOC         6.7     7.0     9.6

            GPP         320       419       435
            Reco        -336      -394      -467

            DIC+DOC     -2.6      -1.6      -2.6
            NEE         -17       25        -32




                         [Sickman et al. in prep]
                  Permafrost Warming Experiment




             0              5 cm           0.0              10 cm          0.0                             0.00
                                                                                            20 cm                           40 cm
                                                                                                           -0.05
             -1                            -0.5                            -0.2
Soil T (C)




                                                                                                           -0.10
                                           -1.0                            -0.4
             -2
                                                                                                           -0.15
                                           -1.5                            -0.6
             -3                                                                                            -0.20
                      + warming            -2.0                            -0.8
                      control                                                                              -0.25
             -4
                  1 2 3 4 5 6 7 8 9 1011          1 2 3 4 5 6 7 8 9 1011          1 2 3 4 5 6 7 8 9 1011           1 2 3 4 5 6 7 8 9 1011



 [S. Natali, unpublished data]
                                                 Climate
                                                          Gradual Warming/snow depth


                                                Extreme Events                 Drought/Fire or Deluge/Flooding


          Vegetation (composition,                                  Permafrost (hydroclimate,
                    physiology)                                       thaw depth, thermokarst)
                                                                  Thermal             Soil moisture, Redox
                                  C structure and
         Nutrients, ET                                           Insulation,
                                  decomposability,
                                                                 Storativity
                                    Microclimate




Soil Gaseous                                         Soil                                      Soil Liquid
   Phase                                         Solid Phase                                     Phase
 CO2/CH4 fluxes     Redox, Ebullition, Efflux      C Storage,            Conductivity,         DOC, DON fluxes
                                                  Accumulation        Connectivity,Redox,
Themes of current wetland research:
•How do interactions between vegetation and thaw depth affect the rate
and nature of soil organic matter formation?

•Soil hydroclimate controls (warming, drought, thermokarst) on
vegetation, organic matter formation, and carbon/energy balance

Approaches currently being used:
•Experimental manipulation of water table and soil temperature (OTCs,
snow depth)

•Gradient studies along ecotone from black spruce to open peatland

•Comparative studies across permafrost regimes (peatlands with intact
permafrost, thermokarst, no permafrost)
Wetland                                    12
                                              Black Spruce: Aerobic/CO2 Dominated
                                                                               25
Gradient/Ecotone




                         Soil Exposed to
                         Thaw (kg C m2)
                                                    Submerged




                                                                                      10 cm Temp oC
                                           10       Oxic                       20
                                            8       Temp                       15
                                                                               10
                                            6
                                                                               5
                                            4
                                                                               0
                                            2
      Black Spruce                                                             -5
                                            0                                  -10
                                             11/5    2/13    5/24    9/1   12/10

                                            Tussock Grass: Intermediate Hydrology
      Willow/Bog Birch                     25                                  25




                         Soil Exposed to
                         Thaw (kg C m2)




                                                                                      10 cm Temp oC
                                                  Submerged                    20
                                           20     Oxic
                                                  Temp
                                                                               15
                                           15                                  10
                                           10                                  5
                                                                               0
                                            5
      Tussock Grass                                                            -5
                                            0                                  -10
                                             11/5   2/13    5/24   9/1    12/10


                                           Emergent Fen: Anaerobic/CH4 Dominated
      Emergent Marsh                       80                                   25
                         Soil Exposed to
                         Thaw (kg C m2)




                                                    Submerged




                                                                                      10 cm Temp oC
                                                    Oxic                        20
                                           60                                   15
                                                    Temp
                                           40                                   10
                                                                                5
      Rich fen                             20                                   0
                                                                                -5
                                            0                                   -10
                                             11/5    2/13       5/24   9/1   12/10
Wetland                                    12
                                              Black Spruce: Aerobic/CO2 Dominated
                                                                               25
Gradient/Ecotone




                         Soil Exposed to
                                                    Submerged




                         Thaw (kg C m2)




                                                                                      10 cm Temp oC
                                           10       Oxic                       20
                                            8       Temp                       15
                                                  CO2                          10
                                            6
                                                  CH4                          5
                                            4
                                                                               0
                                            2                                  -5
      Black Spruce                          0                                  -10
                                             11/5     2/13   5/24    9/1   12/10

                                            Tussock Grass: Intermediate Hydrology
      Willow/Bog Birch                     25                                  25




                         Soil Exposed to
                         Thaw (kg C m2)




                                                                                      10 cm Temp oC
                                                    Submerged
                                           20       Oxic                       20
                                                    Temp                       15
                                           15     CO2                          10
                                           10     CH4                          5
                                                                               0
                                            5
      Tussock Grass                                                            -5
                                                                               -10
                                            0
                                             11/5     2/13   5/24   9/1   12/10


                                           Emergent Fen: Anaerobic/CH 4 Dominated
      Emergent Marsh                       80                                   25
                         Soil Exposed to
                         Thaw (kg C m2)




                                                    Submerged




                                                                                      10 cm Temp oC
                                                    Oxic                        20
                                           60                                   15
                                                    Temp
                                           40   CO2                             10
                                                CH4                             5
      Rich fen                             20                                   0
                                                                                -5
                                            0                                   -10
                                             11/5     2/13      5/24   9/1   12/10
                                           Hydroclimate
                                                                                                                             50




                                                                                                  Pmax (mol CO2 m-2 s-1)
                                                                                                                             40


                                           manipulations
                                                                                                                             30
                                                                                                                             20
                                                                                                                             10                              Veg controls
                         -2.5
                                   No warming       Warming                                                                   0
                                                                       GPP ~ PAR, WT                                           205       210          215     220    225        230
NEE (mol CO2 m-2 s-1)




                          -2    WT plot (p=<0.01)
                                                                                                                                                  Xmax (julian day)

                         -1.5                                                                                                -10




                                                                                                    GPP (mol CO2 m-2 s-1)
                                                                                                                                     Hydroclimate
                                                                                                                             -8
                          -1                                           ER ~ WT, temp                                                 controls
                                                                                                                             -6
                         -0.5
                                                                                                                             -4
                           0
                                                                                                                             -2

                         0.5                                                                                                  0
                                 Control        Lowered       Raised                                                              -65   -55     -45    -35    -25   -15    -5    5
                                                                                                                                              WT (cm beneath moss)


                           8
                                WT plot x warming (p=<0.01)




                                                                                        CH4 flux (mg m -2 d-1)
                           7                                                                                                400         Raised
                                                                                                                                        Control
mol CH4 m-2 min-1




                           6                                                                                                300         Lowered
                                                                       CH4 ~ WT, temp
                           5
                                                                                                                            200
                           4
                           3                                                                                                100
                           2
                                                                                                                              0
                           1
                           0                                                                                                  -70 -60 -50 -40 -30 -20 -10 0 10
                                 Control        Lowered       Raised                                                                 Mean daily WT position (cm)
Hydroclimate
manipulations                160
                             140
                             120
                             100




                mg DOC l-1
                              80
                              60
                              40
                              20
                               0
                             -20                             R2=0.32
                             -40
                                   0     20   40   60   80   100    120
                                       Depth to seasonal ice (cm)
      PERMAFROST, HYDROLOGY AND STREAM SOLUTES
Task I/S1: Monitoring patterns of retention and loss of water, carbon and nitrogen from watersheds with
differing permafrost extent and stability


                                              Climate


                                                         Fire
                                                    (Frequency &
                                                      Intensity)

     Permafrost
(extent, thaw depth,                              Vegetation
    thermokarst)                                  (spruce vs.
                                                  hardwoods;
                                                    moss)
                                                                                          Soil
                                                                                       composition


      Soil moisture/
      groundwater                                          Stream
           flows                                        hydrology and
                                                           solutes

                                                                           Fluvial exports
                          PERMAFROST, HYDROLOGY AND STREAM SOLUTES
                  120
                        C2 (4%)
                                                                                                                              600
                  100                                                                        1.25




                                                                                                                                                                            DOC concentration (mgC/L)
                                                                                                                                                                                                        • Hydrograph




                                                                                                    N concentration (µgN/L)
                                                                                                                              500                                       8




                                                                       Flux (kgN ha-1 y-1)
                   80                                                                        1.00
                                                                                                                              400                                       6                               separation using
                   60                                                                        0.75
                                                                                                                                                                                                        EMMA (PCA based
                                                                                                                              300
                                                                                                                                                                        4
                   40                                                                        0.50
                                                                                                                              200
                                                                                                                                                                                                        approach)
                   20                                                                        0.25                             100
                                                                                                                                                                        2
                                                                                                                                                                                                        • Four flowpaths: Q1
                    0                                                                        0.00                              0                                        0                               from soils, Q2, Q3 &
                           Jun            Jul            Aug                                                                        Dep Strm Flux Nitrate   DON   DOC
                                                                                                                                                                                                        Q4 from deeper source
                  800                                                                                                         600                                                                       waters
                        C4 (19%)                                                             1.25




                                                                                                                                                                            DOC concentration (mgC/L)
                                                                                                    N concentration (µgN/L)
                                                                                                                              500                                       8




                                                                       Flux (kgN ha-1 y-1)
                                                                                                                                                                                                        • Soil water dominant
Discharge (L/s)




                  600                                                                        1.00
                                   Q1                                                                                         400                                       6
                                   Q2                                                        0.75                                                                                                       source in the C3
                                   Q3                                                                                         300
                  400
                                                                                             0.50
                                                                                                                                                                        4                               stream, Q2 dominant
                                   Q4                                                                                         200                                                                       source in C2 and C4
                  200                                                                        0.25                                                                       2
                                                                                                                              100
                                                                                                                                                                                                        • Coupled to patterns
                                                                                             0.00                              0                                        0
                    0                                                                                                               Dep Strm Flux Nitrate   DON   DOC                                   in hydrology, the high
                           Jun            Jul            Aug                                                                                                                                            permafrost watershed
                  600
                        C3 (53%)                                                                                              600                                                                       has highest DOC, but
                                                                                             1.25




                                                                                                                                                                            DOC concentration (mgC/L)
                                                                                                                                                                                                        lowest nitrate
                                                                                                    N concentration (µgN/L)




                  500                                                                                                         500                                       8
                                                                       Flux (kgN ha-1 y-1)




                                                                                             1.00                                                                                                       concentrations
                  400                                                                                                         400                                       6
                                                                                             0.75
                  300                                                                                                         300                                                                       • Lower nitrate in the
                                                                                                                                                                        4
                  200
                                                                                             0.50
                                                                                                                              200                                                                       high PF stream
                                                                                             0.25                             100
                                                                                                                                                                        2                               indicative that shallow
                  100
                                                                                             0.00                              0                                        0
                                                                                                                                                                                                        soil not the source of
                    0                                                                                                               Dep Strm Flux Nitrate   DON   DOC                                   DIN to streams
                           Jun            Jul            Aug
                                        (from Jones et al., in prep)                                                                          (from Jones et al., 2005)
                                            FIRE AND STREAM SOLUTES

                                                                                                    • Fire had a dramatic effect
                                                                                                    on stream solutes
                         2002                            2005
                                                  C1                                                • Stream nitrate
                  1.00                            P6                                                concentration increased
                  0.75                                                                              ~130% (SO4= and K+ also
                  0.50                                                                              increased)
                  0.25                                                                              • Increase potentially due
                  0.00                                                                              to reduced competition
                                                                                                    between vegetation and
                         2003                            2006                                       soil microbes (nitrification),
Nitrate (µgN/L)




                  1.00                                                                              or increase in active layer
                                                                                                    depth and flushing of
                  0.75                                                                              deeper stores
                  0.50
                                                                                                    • Stream DOC declined
                  0.25                                                                              22% (DON, DOC:DON and
                  0.00                                                                              Ca2+ also declined)
                                                                                                    • Decline potentially due to
                         2004                            2007
                                                                                                    combustion of soil carbon,
                  1.00
                                                                                                    transformation of soil
                  0.75                                                                              carbon to less soluble
                  0.50                                                                              compounds, or decline in
                                                                                                    soil carbon mineralization
                  0.25
                  0.00
                         May    Jun   Jul   Aug    Sep   May    Jun     Jul     Aug      Sep
                                                                (from Betts and Jones, in review)
                                       SOURCE WATER AND DOM QUALITY
               DOM quality measured by one-month bioassays                                                                 DOM composition measured by fluorescence
                                                                                                                           excitation & emission
                                                                                                                                                 Streams
                 60   a.
                                                      4C                                                                   Thermokarsts
                                                      4C + nutrients




                                                                      Components 9 and 10 (%)
                                                      25 C
                                                                                                                           5
                 40                                   25 C + nutrients




                                                                                                Component 1 (%)
                                                                                                                           0




                                                                                                                  PCA 2
                 20
                                                                                                                           -5
DOC loss (%)




                  0
                            C2         C4          C3            CJ                                                       -10
                           (4%)       (19%)       (53%)                                                                            Springs

                      b.                                                                                                  -15
                 60                                                                                                          -20   -15   -10    -5    0    5    10
                                                                                                                                               PCA1

                 40                                                                                  • Axis 1 related to reduction-oxidation potential of DOM
                                                                                                                            Component 2 (%)
                                                                                                     (oxidized/reduced quinone)
                                                                                                                                         Component 8 (%)
                                                                                                     • Axis 2 related to DOM quality (tyrosine and tryptophan)
                 20
                                                                                                     • DOM from thermokarsts of low quality, whereas springs
                                                                                                     flowing from shallow source waters enriched in labile
                  0                                                                                  DOM
                       C3-1         C3-2      C4-1        K1     K2
                                                                                                     • Within streams, DOM tends to be fairly recalcitrant.
                           (from Balcarczyk et al., in review)                                       Labile DOM rapidly consumed near source

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:33
posted:9/14/2012
language:English
pages:20