Response of Cross-biome Productivity to the Early 21st Century Drought

Authors: PONCE CAMPOS, G.E. - University Of Arizona; Moran, Mary; HUETE, A. - University Of Technology Sydney; ZHANG, Y. - University Of Arizona; BRESLOFF, C. - University Of Arizona; HUXMAN, T.E. - University Of Arizona; Bosch, David - Dave; Buda, Anthony; Gunter, Stacey; KITCHEN, S.G. - Us Forest Service (FS); MCNAB, W.H. - Us Forest Service (FS); MCCLARAN, M. - University Of Arizona; Morgan, Jack; Peters, Debra; Sadler, Edward; Seyfried, Mark; Starks, Patrick; Montoya, Ann; HEARTSILL SCALLEY, T. - Us Forest Service (FS); EAMUS, D. - University Of Technology Sydney

Submitted to: American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: 12/8/2012
Publication Date: 12/8/2012
Citation: Ponce Campos, G., Moran, M.S., Huete, A., Zhang, Y., Bresloff, C., Huxman, T., Bosch, D.D., Buda, A.R., Gunter, S.A., Kitchen, S., Mcnab, W., Mcclaran, M., Morgan, J.A., Peters, D.C., Sadler, E.J., Seyfried, M.S., Starks, P.J., Montoya, A.D., Heartsill Scalley, T., Eamus, D. 2012. Response of Cross-biome Productivity to the Early 21st Century Drought. [abstract]. American Geophysical Union Fall Meeting, San Francisco, CA. December 3 - 7,2012.

Interpretive Summary: The response of ecosystem productivity to contemporary drought coupled with record warming presents important challenges to predictive ecological modeling. In this study, we investigated the response of annual above-ground net primary production (ANPP) to precipitation variability during the early 21st century drought (2000-2009). The analysis combined satellite estimates of vegetation greenness with meteorological data from in situ climate network stations at experimental sites across a range of biomes from grassland to forest in Northern and Southern Hemispheres. We found that despite enduring prolonged warm drought conditions, all biomes retained their ANPP sensitivities to mean annual precipitation. Rain use efficiencies (RUE = ANPP/precipitation) were highest for the grassland and decreased with higher precipitation over the humid forest sites. For the most extreme drought conditions in the driest years, cross-biome RUE converged to a common, maximum rain use efficiency (RUEmax) that exceeded values previously reported. These results have implications for predicting productivity responses to potential climate change across a range of terrestrial biomes. The satellite-based approach demonstrated here may provide a means of monitoring productivity at experimental sites to better understand the consequences of predicted climate change on food security and resource management.

Technical Abstract: The response of ecosystem productivity to contemporary drought coupled with record warming presents important challenges to predictive ecological modeling. In this study, we investigated the response of annual above-ground net primary production (ANPP) to precipitation variability during the early 21st century drought (2000-2009). The analysis combined satellite estimates of vegetation greenness with meteorological data from in situ climate network stations at experimental sites across a range of biomes from grassland to forest in Northern and Southern Hemispheres. We found that despite enduring prolonged warm drought conditions, all biomes retained their ANPP sensitivities to mean annual precipitation. Rain use efficiencies (RUE = ANPP/precipitation) were highest for the grassland and decreased with higher precipitation over the humid forest sites. For the most extreme drought conditions in the driest years, cross-biome RUE converged to a common, maximum rain use efficiency (RUEmax) that exceeded values previously reported. These results have implications for predicting productivity responses to potential climate change across a range of terrestrial biomes. The satellite-based approach demonstrated here may provide a means of monitoring productivity at experimental sites to better understand the consequences of predicted climate change on food security and resource management.