Ecophysiological responses of Chihuahuan desert grasses to fire

To better understand the effects of fire in the Chihuahuan desert, gas exchange characteristics of two dominant grass species, Bouteloua eriopoda and Aristida purpurea, and soil nitrogen availability were studied in response to prescribed fire at the Jornada Experimental Range in southern New Mexico. Burned and unburned plant individuals we re measured before and after fire. Rates of net photosynthesis and stomatal conductance were highest in burned individuals, with those of A. purpurea exceeding B. eriopoda. Soil nitrogen supply rates increased compared to unburned controls. Similar to other grasslands where fire is common, physiological characteristics of vegetation responded positively. These adaptations indicate that fire may be beneficial in the preservation and restoration of native grasses. (c) 2008 Elsevier Ltd. All rights reserved.