1 / 46

Terrestrial Carbon Sequestration

Terrestrial Carbon Sequestration. Jay Angerer Texas AgriLife Research Blackland Research and Extension Center September 3, 2010. Outline. Introduction Global Carbon Cycle Plant processes Terrestrial Sequestration Forests Cropland Rangeland Disturbed or denuded land. Outline (cont.).

tracen
Télécharger la présentation

Terrestrial Carbon Sequestration

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Terrestrial Carbon Sequestration Jay Angerer Texas AgriLife Research Blackland Research and Extension Center September 3, 2010

  2. Outline • Introduction • Global Carbon Cycle • Plant processes • Terrestrial Sequestration • Forests • Cropland • Rangeland • Disturbed or denuded land

  3. Outline (cont.) • Other Benefits • Potential Pitfalls • Monitoring and Measurement • Decision Support Tools

  4. Where Does Terrestrial Sequestration Fit? From: http://www.netl.doe.gov/technologies/carbon_seq/overview/ways_to_store.html

  5. Terrestrial Carbon SequestrationDefined • From Lal et al. (2004): “Carbon sequestration implies transferring atmospheric CO2 into long-lived pools and storing it securely so it is not immediately reemitted. Thus, soil C sequestration means increasing Soil Organic Carbon (SOC) and Soil Inorganic Carbon (SIC) stocks through judicious land use and recommended management practices (RMPs).”

  6. Global Carbon Cycle From: http://www.netl.doe.gov/technologies/carbon_seq/overview/what_is_CO2.html

  7. Plants as “Injectors” From: http://www.epa.gov/sequestration/local_scale.html

  8. Local Carbon Cycle Photosynthesis From: http://www.fao.org/es/esa/pesal/role2.html

  9. Photosynthetic Pathway Differences • C3 Pathway – better able to acquire CO2 with increasing CO2 (fertilizer effect) • Rice, barley, wheat, most trees • C4 Pathway – CO2 is “pumped” into inner leaf cells to reduce water loss. • Does not respond as much to increasing CO2 • May be beneficial to C sequestration in hot, dry environments • Corn, tropical grasses From: http://www.geo.arizona.edu/palynology/geos462/14rockvarnish.html

  10. Pathways of Terrestrial Carbon From Lal et al. 2004. Science 304, 1623

  11. Carbon Sequestration: Forests • Reforestation – replanting areas where trees have been removed • Afforestation – planting trees in cropland • Increasing tree growth – increase biomass of tree species • Increasing permanence of forest products – reduce “throw-away” tendencies • Decreasing the loss of current forested areas

  12. Carbon Sequestration Rates and Saturation Periods: Forests From: http://www.epa.gov/sequestration/rates.html

  13. Forest Carbon Sequestration Programs • Reforestation of degraded lands with fast growing tree species • Urban tree planting • Fire management of forests and surrounding areas • Change other management practices (e.g. logging procedures)

  14. Cropland Carbon Sequestration • Changes in crop management • No-till • Minimum-till • Conversion to grassland • Manure management • Fertilizers • Irrigation • Increased use of legumes

  15. Carbon Sequestration Rates and Saturation Periods: Ag Lands From: http://www.epa.gov/sequestration/rates.html

  16. Soil Carbon Dynamics In Response To Tillage SOIL CARBON (% OF ORIGINIAL) IN RESPONSE TO CULTIVATION 100 Perennial Vegetation Conservation Tillage Plowing 50 SOILCARBON 0 1 50 years

  17. Factors Affecting Sequestration • Soil texture (sand, silt, clay percentages) • Soil profile characteristics (depth, rocks) • Climate (temperature, humidity, rainfall) • Rates can range from: • 0 to 150 kg C/ha per year in dry and warm regions • 100 to 1000 kg C/ha per year in humid and cool climates From: Lal et al. 2004. Science 304, 1623

  18. Potential Losses • Soil Erosion • Removal of residues and mulch can increase erosion • Deposition in channels or in aquatic systems • Deposition is 0.4 to 0.6 Gt C/year • 0.8 to 1.2 Gt C/year is lost to exposure to atmosphere • Must assess carbon used for crop management • Plowing • Fertilizer application • Chemical Use • These must be accounted for to get the proper offset From: Lal et al. 2004. Science 304, 1623

  19. Biochar for Improving Ag Soils • Fine grained, highly porous charcoal • Used as a soil amendment which improves soil physical and chemical properties • Can increase site productivity • First used by Amazonian natives

  20. Rangeland Carbon Sequestration • Rangelands are generally characterized as grasslands or shrublands that are not suitable for consistent crop production • Occupy almost 50% of worldwide land area • Carbon sequestration would require changes in grazing management • Reduced stocking rate or livestock removal • Grazing systems

  21. Improved resource management Reduce wildfires Reduce water and wind erosion Restore overgrazed and denuded areas Conversion of cropland to grazingland Introduce/promote nitrogen fixing legumes Rangeland Carbon Sequestration

  22. Carbon Sequestration Rates and Saturation Periods: Rangelands From: http://www.epa.gov/sequestration/rates.html

  23. Issues with Rangeland Carbon Sequestration • Large land area, but relatively low carbon storage • In US, most rangelands are privately owned or are public lands (e.g. BLM land) • High degree of uncertainty in sequestration estimates for most regions • Need large land areas to be attractive to potential buyer or as an offset • May require development of government programs for assisting farmers/ranchers in joining carbon sequestration programs

  24. Assessing Carbon Sequestration Potential for Programs

  25. Sequestration Potential for Southwest Region

  26. Uncertainty Analysis • Uncertainty in prediction of carbon sequestration on agricultural lands can be high, especially on rangelands • Lack of quantitative information on carbon sequestration for various practices and locales • Models need to be calibrated to these conditions • An uncertainty analysis was conducted using carbon modeling results for southwest region

  27. Assessing Uncertainty for Southwest Region • The estimated amount of carbon sequestered and its associated uncertainty were mapped • A weighted averaging procedure was used based on soil texture, soil map unit, major land resource area, and county. • Spatially explicit maps of the carbon sequestered and uncertainty were produced

  28. Sequestration on Disturbed Lands • Issues affecting carbon • Exposure of soil • Water Erosion • Wind Erosion • Carbon depleted to point where soil amendments may be required

  29. Sequestration on Disturbed Lands • Degraded or denuded land offers opportunity to replace/sequester carbon • Fast growing tree species • Grasses or grass/legume mix • Biochar?

  30. Potential Sequestration Rates From: Lal et al. 2004. Science 304, 1623

  31. Other Benefits of Terrestrial Sequestration • Improved Ecosystem Services • Cleaner water • Cleaner air • Improved soil fertility • Improved biodiversity • Potential for monetary benefits • Carbon trading/offsets

  32. Pitfalls • Interactions with biofuel production • Land areas may be used for biofuel production rather than C sequestration • Implications for food security/livelihoods • In the case of livestock producers, may reduce land available for grazing • Increasing population may drive land use change to meet food security needs and negate carbon gains

  33. Pitfalls • Leakage • The IPCC Special Report (2000) defines leakage as "the unanticipated decrease or increase in greenhouse gas (GHG) benefits outside of the project's accounting boundary as a result of project activities." • Example: For a forest under a C sequestration program, logging may be displaced to an area outside the Project area. The CO2 emissions that result from the displaced logging could partially or completely negate the benefits of avoiding CO2 emissions in the protected forest.

  34. Monitoring and Verification • Monitoring • Are (or where) the contracted practices being applied? • Verification • Are the contracted practices sequestering carbon • Evaluation • Is their leakage? Is there proper accounting? • Reporting • Is the project meeting contract goals?

  35. Monitoring and Verification • Generally need to sample large area in multiple places to get a reasonable representation of carbon amounts • Rangelands with non-uniform vegetation and terrain require more sampling • Samples using conventional lab analyses are expensive to process • Terrestrial sequestration verification would be too expensive to do with conventional methods.

  36. Measurements of Soil Carbon • Develop improved technologies and systems for direct measurements of soil carbon • Two Methods • Laser induced breakdown spectroscopy (LIBS) • Near Infrared Reflectance Spectroscopy (NIRS) • Allow rapid scans of samples in the field • Examine correlation of results with other technologies • Principles for cost effective sampling

  37. LIBS System

  38. Portable NIRS System

  39. Simulation Models and Decision Support Tools • Models can be used to assess carbon sequestration potential for a given area • Provide the ability to examine different management alternatives for carbon gain • Allow examination of other outputs such as erosion and water quality under the selected practice

  40. Simulation Models • CENTURY Model • Model and Documentation http://www.nrel.colostate.edu/projects/century5/ • Online tool: http://www.cometvr.colostate.edu/ • APEX and EPIC Model • http://epicapex.brc.tamus.edu/ • COLE (Carbon OnLine Estimator): Web-based Tool for Forest Carbon Analysis • http://www.ncasi2.org/COLE/

  41. Carbon Decision Support Tool

  42. Homework • Read two journal articles: • Soil Carbon Sequestration Impacts on Global Climate Change and Food Security R. Lal (11 June 2004) Science304 (5677), 1623. • Soil carbon sequestration to mitigate climate change and advance food security. R. Lal, et al. Soil Sci 172 no12 D 2007

  43. Questions?

More Related