Effects of Fire on Litter, Forage Dry Matter Production, and Forage Quality in Steppe Vegetation of Eastern Anatolia, Turkey

Abstract

The effect of fire on vegetation of semi - arid steppe has not bee n studied extensively. Wildfires are rare in some steppe rangelands because of high levels of large herbivore grazing. However, grazing is sometimes restricted or excluded in areas such as national parks or the areas where afforestation projects are conduc ted. Therefore, sometimes, wildfires occur during the dormant season when litter ( the uppermost layer of organic debris on the soil surface; essentially the freshly fallen or slightly decomposed vegetal material ) mass has resulted in peak levels. Our study assessed the effects of a single fire on litter mass, forage production, and forage crude protein, Neutral Detergent Fiber (NDF), and Acid Detergent Fiber (ADF) in high altitude rangelands of Eastern Anatolia. We found significant effects of treatment (fi re and no fire), years, and sampling date on all variables. Following the prescribed fire in 2011, litter mass and forage production was less in treated plots compared to untreated control plots during both years. The effect of the fire on litter and forag e production was more pronounced in 2012 compared to 2013. The effects of the fire on forage quality variables were also greater in 2012 than in 2013. Forage crude protein levels were consistently higher in treated plots during all 2012 sampling periods. S imilarly, NDF and ADF tended to be lower in treated plots relative to the control plots during 2012. All effects we found were more pronounced in the first growing season following the fire compared to the second growing season, suggesting a relatively tra nsient nature of fire effects in the steppe vegetation we studied. Keywords: ADF, Litter mass, NDF, O rganic debris, Semi - arid rangelands.