Submitted to: Ecological Society of America Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 7/4/2002
Publication Date: 8/4/2002
Citation: MITCHELL, K.A., PETERS, D.C., HERRICK, J.E., MONGER, H.C. LONG-TERM CHANGES IN CARBON POOLS ACCOMPANYING SHRUB INVASION OF A DESERT GRASSLAND: THE JORNADA EXPERIMENTAL RANGE, 1850-TODAY. 87TH ANNUAL MEETING OF THE ECOLOGICAL SOCIETY OF AMERICA. 2002. ABSTRACT P. 215.
Technical Abstract: Coincident with a worldwide increase in the abundance of woody plants within former grasslands, desert grasslands throughout the southwestern U.S. have experienced a substantial increase in the abundance of shrubs during the last century. The displacement of grasslands with grass-shrublands has had important implications for ecosystem carbon cycling and rates of carbon sequestration. Building on a history of biogeochemistry research conducted at the Jornada Experimental Range in southern New Mexico, we measured and modelled aboveground and belowground carbon storage in black grama grasslands (Bouteloua eriopoda) and mesquite (Prosopis glandulosa) and creosotebush (Larrea tridentata) shrublands across the Jornada basin. We combined the simulation modeling predictions of the CENTURY model with data from recovered historical vegetation maps of 1858, 1915, 1928 and modern vegetation maps. Our results support the hypothesis that shrub encroachment into grasslands increases storage of belowground carbon. Landscape-level mapped estimates of carbon pools indicate that the desert grassland ecosystem of the Jornada basin may have served as a carbon sink during the last century.