Dr. Robert O. Lawton
Professor
Department of Biological Sciences
Research Area
Ecology
Research Description
I am fascinated by the structure and dynamics of species-rich forests, particularly tropical cloud forests. Defined by, and dependent upon, immersion in cloud, cloud forests characteristically occur in tropical mountains where air is forced by the terrain to rise to the lifting condensation level -- the point of cloud formation. I am involved in collaborative projects, funded by NASA and NSF, which investigate the processes - both local and regional - influencing cloud formation and the interception of cloud water in the Cordillera de Tilarán of northern Costa Rica, home to the well-known Monteverde cloud forests.
In the windswept Monteverde cloud forests, strong gradients in forest structure and species composition parallel a gradient of exposure to wind and cloud, which may be changing due to global and regional influences. I am part of a group establishing a research program to evaluate species distribution and performance along this changing gradient. Windthrow of trees is common in these forests, and concentrated during strong winter storms associated with outbreaks of North American polar air. Demographic analyses of a dominant tree species suggest, however, that these forests are in equilibrium with chronic disturbance by storms. Ongoing monitoring is aimed at addressing temporal variation in storm disturbance due to climatic oscillations such as the El Nino/Southern Oscillation, and the relation of spatial variation in the pace of community dynamics to community composition.
In addition to my cloud forest research interests, I work with students to study various problems in temperate forest plant ecology and population dynamics. I am also involved with the UAH Natural Products Research Group, and share with my wife, Dr. Marcy F. Lawton, a serious interest in corvids.
Selected Publications
Lawton, R. O. , U. S. Nair, D. K. Ray, A. Regmi, A. Pounds, & R. M. Welch. in press. Quantitative measures of immersion in cloud and the biogeography of cloud forest. In: Mountains in the Mist: Science for conserving and managing tropical montane cloud forest. L. A. Bruijnzeel, J. Juvik, F. N. Scatena, L. S. Hamilton & P. Bubb (eds.) University of Hawaii Press.
Nair, U. S., D. K. Ray, R. O. Lawton, R. M. Welch, R. A. Pielke, Sr., & J. Calvo. in press. Impact of deforestation on orographic cloud formation in a complex tropical environment. In: Mountains in the Mist: Science for conserving and managing tropical montane cloud forest. L. A. Bruijnzeel, J. Juvik, F. N. Scatena, L. S. Hamilton & P. Bubb (eds.) University of Hawaii Press.
Ray, D.K., U. S. Nair, R. O. Lawton, R. M. Welch, & R. A. Pielke, Sr. in press. Impact of land use on Costa Rican tropical montane cloud forests: 2. Sensitivity of orographic cloud formation to deforestation in the plains. J. Geophysical Research.
Setzer, M. C., D. M. Moriarity, R. O. Lawton, W. N. Setzer, G. A. Gentry & W. A. Haber. 2003. The medicinal value of tropical cloud forest plants from Monteverde, Costa Rica. J. Tropical Biology 31(3-4): 647-674.
Nair, U. S., R. O. Lawton, R. M. Welch, and R. A. Pielke. 2003. Impact of land use on Costa Rican tropical montane cloud forests: 1. Sensitivity of cumulus cloud fields to lowland
deforestation. J. Geophysical Research - Atmospheres. Paper 10.1029/2001JD001135.
Lawton, R..O., U. S. Nair, R. A. Pielke, Sr., R. M. Welch. 2001. Climatic impact of tropical lowland deforestation on nearby montane cloud forests. Science 294: 584-587.
Nadkarni, N., R. O. Lawton, K. L. Clark & T. Matelson. 2000. Ecosystem ecology and forest dynamics. In, N.Nadkarni and N. Wheelwright (eds), Monteverde: Ecology and Conservation of a Cloud Forest. Oxford University Press.
Clark, K., R. O. Lawton, and P. R. Butler. 2000. The Physical Environment. In, N. Nadkarni and N. Wheelwright (eds), Monteverde: Ecology and Conservation of a Cloud Forest. Oxford University Press.
Talley, S. M., R. O. Lawton, and W. N. Setzer. 1996. Host preferences of Rhus radicans (Anacardiaceae) in a Southern deciduous hardwood forest. Ecology 77(4): 1271-1276.
Williams-Linera, G. and R. O. Lawton. 1995. The ecology of hemiepiphytes. In, M. Lowman and N. Nadkarni (eds.), Forest Canopies. Academic Press.
Williams, D. A., M. F. Lawton, and R. O. Lawton. 1994. Population growth, range expansion,and competition in the cooperatively breeding brown jay, Cyanocorax morio. Animal Behavior 48: 309-322.
