1 / 25

Fire and prairie

Explore the historical factors shaping North American prairies, from uplifted Rocky Mountains creating rain shadows, to the vital role of fire, climate, and grazers. Learn about the adaptation of native grasses to drought, fire, and grazing, and the significance of warm and cold season grasses in the diverse prairie landscapes. Discover the impact of fire suppression on prairie diversity and the importance of implementing effective fire regimes for managing invasive species and enhancing biodiversity. Engage in practical discussions and outcomes for sustainable prairie ecosystem management.

lholman
Download Presentation

Fire and prairie

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. Fire and prairie Oct 12, 2010 From: http://www.cibolo.org/prairie

  2. Origin of North American Prairies • Uplift of Rocky Mountains created a rain shadow • Retreat of glaciers • Historically shaped by fire, climate, and grazers/browsers http://www.birdcanada.com/2009/11/a-whole-lot-of-empty/

  3. Uplift and rain shadow

  4. “The Great American Desert”

  5. Three prairies? • Western (“shortgrass”) prairie too dry to support much woody vegetation • Eastern (“tallgrass”) prairie can support broken to closed canopy forest • this shows the importance of fire to this region – with fire it is a grassland • Mixed grass prairie is between these two regions From: Anderson, RC. 1990. The historic role of fire in the North American Grassland. In: Colins, S, Collins, SL, Wallace, L. eds. Fire in North American Tallgrass Prairies.

  6. Tallgrass Prairie

  7. Mixed Grass Prairie

  8. Shortgrass Prairie

  9. Why grass in grasslands? • What adaptations do grasses have to drought? • To fire? • To grazers? • Basal meristems • Above ground • dormancy •  C4 photosynthesis • in some grasses

  10. Warm and cold season grasses • Warm Season (C4) Cool Season (C3) C4 have a competitive advantage under drought and high temperatures: C3 uses 833 molecules of water per CO2 molecule fixed vs 277 water molecules used by C4 Water use efficiency! • Examples C4 : big bluestem, indiangrass, bermudagrass, switchgrass, corn, sugar cane • Examples C3 : orchardgrass, fescues, and perennial ryegrass

  11. Time of burning: warm and cold season grasses

  12. Time of burning: perennial and annual forbs

  13. What happens with fire suppression?

  14. What happens with no disturbance?

  15. No Diversity

  16. Other sources of disturbance? • Grazing and browsing • Bison followed fires • Result: patchy Mosaic

  17. Grazing

  18. Browsing

  19. Patch Burn Grazing • Cattle focus on grasses instead of forbs • Replicates historical patterns • http://www.nrem.iastate.edu/research/patchburn/index.html

  20. Prairie Fire regime? • Frequency? Season? • Late spring fire suppresses cool-season grasses • Early spring or fall fires favors cool-season grasses over warm-season grasses

  21. TTYGroup: Practical Questions • A property has a remnant prairie, but is composed mostly of cool season invasive grasses such as smooth brome and kentucky bluegrass. What fire regime/ management practices would you recommend to manage this property to eventually reduce the invasive species and increase diversity?

  22. TTYGroup: Practical Questions 2. A property has been restored, and is mostly composed of warm season native grasses such as big bluestem and indian grass. What fire regime/management practices would you recommend to maintain these species and increase diversity?

  23. TTYGroup - Outcomes • Complete the outcome sheet with your group

More Related