Managing uplands in the sagebrush steppe
•Transferir como PPTX, PDF•
1 gostou•922 visualizações
The factors influencing vegetation (and thus habitat) in the sagebrush-steppe have changed dramatically in the past 100 years. There is clear evidence that the introduction of invasive species such as cheatgrass and medusahead has changed the way plant communities function and increased fire risk. Projections of future climate suggest fire risk will continue to increase over time. Informed management will play a key role in mitigating the loss of native plant communities in the future.
Recomendados
Mais conteúdo relacionado
Mais procurados
Mais de Conrad Communications
Mais de Conrad Communications (16)
Último
Último (20)
Managing uplands in the sagebrush steppe
- 1. Kirk Davies, Chad Boyd, and Tony Svejcar USDA-ARS, Burns, OR
- 6. Increase in wildfires is a global and local issue Most models suggest fire will become more frequent and severe Fuel management is critical to limiting fire risk and severity Rangelands are expansive, thus limiting options Grazing is the only treatment that is feasible across large landscapes
- 7. Northern Great Basin Experimental Range Not grazed since 1937 Both grazed and ungrazed plots burned in 1993
- 8. 3 times fuel loads on PG Increased fuel depth Current year’s biomass equal Ungrazed Grazed
- 9. Grazed Burned 15 yrs post-fire Ungrazed Burned 15 yrs post-fire Native perennial grasses Light colored vegetation is cheatgrass
- 10. Grazed in Nov –March for 4 years. Compared to adjacent non-grazed sites . Burned in Sept 2014
- 12. Date July August September Fuelmoisture(%) 0 20 40 60 80 Ungrazed Winter grazed * * * * * Fuel moisture of extinction
- 14. Grazing can decrease wildfire risk Also increase resilience to wildfire Lower temperature More unburned patches Grazed areas are more suppressible Slower moving fire Reduced flame lengths Allows for direct attack Effect will vary by community composition and fire weather Needs to be a strategic and flexible plan
- 15. QUESTIONS?
Notas do Editor
- Nice-looking native community that provides a multitude of ecosystems services.
- Fires were a part of the sagebrush steppe, but with the additions of invasive annuals, esp. cheatgrass and medusahead, things have changed.
- Continuous fuel load –much higher risk of wildfires. Will we be stuck with annuals and what seems like a never – ending cycle of fire and more cheatgrass –HAVE WE CROSSED A THRESHOLD? Most would say yes – And we are not good at restoring these systems. What does the future hold for these shrubs? Next lightning strike and they are gone.
- Root and shoot mass after 6 weeks of growth under pretty ideal conditions. Cheatgrass on left, bluebunch wheatgrass on right – who will win out in this race to extract soil water and nutrients!
- Exclosures are at Northern Great Basin Experimental Range 35 miles west of Burns
- Much more deal material in ungrazed – this explains the next graph of fuel moisture.
- Below the line the chances of wildfire spreading are much higher (dry fuel). So the period of risk is drastically reduced with winter grazing.
- These are actual fire results from the September 2014 burn. This burn was done during the active wildfire season.