Carbon Sequestration and Cycling

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1 Carbon Sequestration and Cycling Darrel Jenerette University of California Riverside Acknowledgements Isaac Park, Amit Chatterjee, Jen Hooper, Edith Allen, Travis Bean US Forest Service, Kearney Foundation, National Science Foundation

2 AB 32: Reducing CA Greenhouse Gases Reduce GHG emissions to 1990 levels by 2020 A further 80% cut by 2050 Cap and Trade market for carbon credits

3 CO 2 and other greenhouse gases are increasing Current (5/31/2015): ppm 10 Years Ago (5/31/2005): ppm 450 ppm CO 2 expected: ~2035 Dr. Pieter Tans, NOAA/ESRL ( and Dr. Ralph Keeling, Scripps Institution of Oceanography (scrippsco2.ucsd.edu/).

4 Dryland Soil 241 Pg C 16%

5 Will drylands sequester or release additional carbon in the future? Temperature CO 2 Ecosystems Precipitation Positive or Negative Feedback?

6 Carbon and Ecosystem Metabolism Net Ecosystem Productivity = Gross Primary Production Respiration Respiration = Autotrophic (plant)+ Heterotrophic (soil) Gross Primary Production Net Uptake 1:1 Net Loss Respiration

7 Sequestration Carbon sequestration is the difference between fixation and respiration, NOT total fixation. Time Scales of NEP are important 30 minute Daily Seasonal Annual Decadal Fire on Soil C: Depends on Temperature >500 C soil C is lost More Moderate Burning: minimal impact on soil C, may enhance sequestration through ash and charcoal

8 Global Distribution of Drylands Jenerette GD, et al Ecohydrology.

9 Pulse Driven Dynamics: A Cross Scale Framework PULSES in DRYLAND Event and Individual Scales Century and Watershed Scales Collins et al Ann. Rev. Ecol. Syst.

10 Dryland Pulses Across Scales Temporal Scale Jenerette et al Functional Ecology Jenerette et al Ecohydrology Jenerette et al Ecology Oikawa et al JGR Biogeosciences Spatial Scale

11 Measuring Ecosystem Carbon Balance Quantifying changes in C pools Direct measurements of C fluxes

12 Change in Carbon Pools Flux = C in Ecosystem(time 2) C in Ecosystem(time 1) Primary Ecosystem C Pools: Soil Plant (above and belowground) San Dimas Lysimeter Experiment: 41 Year Changes in Soils 0.09 kg m -3 yr -1 San Dimas (Ulery et al. 1995) 5-10 times rates from older and moister grassland soils in N California

13 Eddy Covariance: Whole Ecosystem CO 2 Fluxes Eddy Covariance Tower

14 Eddy-covariance instrumentation Fast response CO 2 Analyzer Fast response 3-D anemometer 30 Minute Measures of: Net CO 2 Flux Energy Balance

15 7 Years of Old Growth (100 year) Chaparral Eddy Covariance Measurements (Sky Oaks) Average C Uptake 52 g C m -2 yr -1 Uptake During Favorable Weather g C m -2 yr -1 Comparable to Old Growth Forests Worldwide g C m -2 yr -1 Luo et al Global Change Biology

16 Given chaparral is important in C cycle, what influences rates of emission and organization of soil C?

17 Santa Rosa Transect of Mediterranean Ecosystems SR7 (2489 m) SR6 (2155 m) 2200 m SR5 (1829 m) SR4 (1592 m) SR3 (1300 m) SR2 (825 m) Santa Rosa Mountain Transect SR1 (289 m)

18 Variation in Soil Organic Matter Content Chatterjee and Jenerette 2011, Landscape Ecology

19 Variation in Soil Organic Matter Spatial Structure Lowest Elevation 0-5cm %LOI (standardized) 30 m Highest Elevation 0-5cm %LOI (standardized) 100 m 30 m 100 m

20 Chatterjee and Jenerette 2011, Landscape Ecology

21 Soil Respiration Summer and Winter 0 Elevation Elevation 3000

22 Soil Respiration Summer and Winter 0 Elevation Elevation 3000 Proportional Contribution of under Canopy SOils

23 Soil Respiration Summer and Winter Soil Respiration Response to Wetting Soil Respiration Response to Wetting and C Addition

24 Variation in Wetting Pulses and Organic Matter Jenerette and Chatterjee Ecology

25 Looking Forward: Assessing Potential for Grass Invasion on Carbon and Other Ecosystem Services Doblas-Miranda Global Ecology and Biogeography

26 Greenhouse Gasses and Climate CO 2 Precipitation Warming

27 Urbanization

28 Nitrogen Deposition

29 Increasing Fire Image: S. Anderson

30 Invasive Exotics

31 Potential for Surprises in Ecosystem Responses to Global Changes Global Change Factors Ecosystem Drivers (e.g Temperature) Ecosystem Sensitivities (e.g. Type Conversion) Ecosystem Functioning Ecosystem Services

32 Carbon Consequences of Grass Invasion Deep Rooting Short Fire Cycle into Chaparral Grass Chaparral Global Change Response Resilience Resistance C Erosion C Photodegradation Soil C

33 Toward Landscape Management of Chaparral 1. Validate Remotely Sensed Grass Invasion Index Satellite Landsat (30m), Seasonal Worldview3: (1m), annual Airborne AVIRIS: 20m pixel, UAV mapping: <1m pixel, on demand Ground-based Phenocams <1m pixel, daily

34 Quantifying Grass Invasion into Chaparral of Angeles Forest Isaac Park

35 Toward Landscape Management of Chaparral 2. Quantify Change in Ecosystem Service Associated with shrub-grass transition Carbon pools Above and belowground Carbon Fluxes Soil, plant and whole ecosystem Erosion Soil NO x production Water

36 In-Situ Soil CO 2 Flux Systems Gore-Tex Soil R calculation: Fick s first law of diffusion FF = DDDD ( dddd dddd ) F-- surface efflux of CO 2 (µmoles m -2 s -1 ) Ds CO 2 diffusion coefficient dc/dz vertical soil CO 2 gradient Oikawa et al JGR Biogeosciences

37 A Scaling Study for Chaparral Ecosystem Services San Dimas Experimental Forest Angeles National Forest Greater Los Angeles Basin Chaparral Landscapes

38 A Scaling Study for Chaparral Ecosystem Services San Dimas Experimental Forest Angeles National Forest Future Projections Past Relationships Greater Los Angeles Basin Chaparral Landscapes

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42 Outline Intro to C dynamics (2.5 min) C in climate change C in metabolism C and sequestration C dynamics in dryland ecosystems (10 min) Distribution of drylands Ecohydrological stommel diagram Shrub-grass transitions Pulse dynamics as organizing framework C in Mediterranean Ecosystems (2.5 min) Santa Rosa Transect Data (10 min) Ongoing research directions (5 min) Our plan invasion Leaf n content analysis? Carbon flux estimates