Effects of Forest Management on Carbon Flux and Storage

1. Effects of Forest Management on Carbon Flux and Storage Jiquan Chen, Randy Jensen, Qinglin Li, Rachel Henderson & Jianye Xu University of Toledo & Missouri Department of Conservation

2. A Few Relevant Advancements in Carbon Study • Global warming associated with human activities is much greater than the portion associated with greenhouse gases (GHG); • Carbon sequestration strength varies with management (e.g., harvesting, fertilization), climate and natural disturbances, but no widely accepted models for managers; • Respiratory carbon loss dominates over the carbon gain through photosynthesis; • Retention of green trees during harvests might prevent a stand from being a carbon source.

3. Qs? Autotrophic respiration Leaf gross photosynthesis Net ecosystem exchange Leaf net photosynthesis Leaf respiration Photorespiration Stem respiration Gross primary production Net primary production Root & mycorrhizal respiration Leaf litter respiration CWD respiration Heterotrophic soil respiration Heterotrophic respiration Soil surface CO2 efflux Ecosystem Carbon Fluxes Atmosphere Photo-tissue Non-photo-tissue CWD Leaf litter Soil Roots Modified from Gifford (2003) by Li & Chen

4. Annual Carbon Storage in N. Hemisphere Forests Gough et al. (2008), Bioscience

5. Growing season NEP for comparable pine ecosystems of various age classes – results of a meta-analysis Euskirchen, Pregitzer & Chen (2006), JGR Gough et al. (2008), Bioscience

6. Effects of clearcut and fire on annual carbon storage by site index at UMBS Gough et al. (2008), Bioscience

7. Hypothesized change in annual carbon storage of disturbed forests Created by J. Chen (2004)

8. Management disturbances will increase the amount of carbon loss through respiration.

9. Changes in elevated respiration rate (%) at MOFEP compartment, showing rapid diminish trends. EAM Difference from the Refs (%) UAM Year

10. Daily mean ecosystem component respiration in the NHM stands

11. Daily mean ecosystem component respiration in the UAM stands

12. Daily mean ecosystem component respiration in the EAM stands

13. Mean respiration (percentage) of different components at the three treatments unit: Kg CO2.ha-2.yr-1

14. Soil respiration not an exponential function of soil temperature – complex regulations! Reduction in photosynthesis (C-gain) at higher VPD (Temperature) will also reduce respiratory C loss!

15. Change in NEE in comparison to low-VPD conditions as a function of VPD at midday. Noormets et al. (2008), New Phytologists

16. Summer respiration (C loss) is linearly related to annual/winter precipitation in California’s Serra Nevada. Concilio et al. (2008), Clim. Change.

17. Ms > 15%. 5 ~ 15%. < 5%. Relationship between soil respiration & temperature • SRR was positively related to Ts5 when Ms >15%. • The positive relationship changed to the negative when Ms <5%. Clearly, water and other resource use and biophyscial environmental variable can alter the conventional Q10 predictions. Ma et al. (2004), For. Sci.

18. Challenges For Managing Ozark Forests • Understand the long-term dynamics of carbon fluxes and regulative mechanisms as climate, species composition, and management practices will be agile; • Link management options directly to carbon storage and fluxes (i.e., credit) in adaptation plans (e.g., climate change and societal needs); • Examine the C credits and sequestration of Ozark forests in context of overall ecosystem functions and services.

19. Thank You!