Research Interests

We have interests in both the physiological and the evolutionary underpinnings of ecological processes and the system-level implications of these processes. Our research centers around fundamental questions of element movement in ecosystems and touches upon such topics as herbivory and tri-trophic interactions, atmospheric chemistry and air pollution, community and ecosystem impacts of biological invasions, and controls over nutrient cycling. We are also very interested in the development and application of analytical technologies in addressing ecological questions.

The Emission and Regulation of Volatile Hydrocarbons

vocFor the last several years much of our attention has been on the regulation of allocation to volatile hydrocarbons (VH) and the processes governing the emission of these compounds from ecosystems to the atmosphere. This research has allowed us to combine our interests in basic ecosystem science, physiological ecology, and applications of ecology. We have worked on the mechanisms governing production of these compounds (e.g., Lerdau et al. 1995; Lerdau and Keller 1997; Funk et al., 2004), the application of evolutionary models and a phylogenetic perspective to hydrocarbon production (Lerdau and Gershenzon 1997; Harley, Monson, and Lerdau 1999; Lerdau and Gray, 2003), and the implications of these emissions for atmospheric chemistry and climate (Keller and Lerdau 1999; Fuentes, Lerdau, Hayden et al. 2000). This research has been supported by grants from NSF and NASA.

The Exchange of Mercury between Ecosystems & the Atmosphere
We are beginning research examining the physiological and ecosystem controls over mercury flux between terrestrial ecosystems and the atmosphere. Preliminary research suggests that terrestrial systems regulate the rate of mercury transfer from the atmosphere to aquatic systems (where Hg is a serious pollutant) and that plant and soil processes control this transfer. This research is conducted in close collaboration with my colleague, Sergio Sañudo-Wilhelmy of Marine Sciences at Stony Brook.

Biological Invasions
We have recently expanded our efforts to examine the ecology of biological invasions. The invasions research, in collaboration with Professor Jessica Gurevitch, a community ecologist, looks at the role of species-specific properties such as nutrient uptake and use patterns, as well as population biology, to understand the impacts that invasions have on large scale properties such as species assemblages, decomposition, and element cycling. This research has been supported by The Nature Conservancy / Mellon Foundation, The US FWS and the US EPA.

Leaf Chemisty and Decomposition

We have recently begun a new project examining the impacts of leaf chemistry on decomposition and nutrient release and the regulation of that chemistry by phylogenetic and ecological factors in the tropical dry forest of Guanacaste, Costa Rica . Previous efforts to identify the impacts of species-specific properties on ecosystem-scale phenomena have been conducted primarily in temperate regions and have been limited by the relatively few number of species present within the community. By focusing on the diverse (but not overwhelmingly so) tropical dry forest we hope to be able to identify and quantify the impacts of allocation to photosynthetic, structural, and defensive compounds on decomposition and nutrient release. This research is supported by the Andrew Mellon Foundation.

Analytical techniques
Our interests in analytical techniques have proceeded along several lines. When our research questions have demanded novel techniques, we have worked with scientists from other disciplines to apply these techniques to ecosystem ecology. For example, in order to identify the carbon sources of isoprene, we have collaborated with John Mak, an atmospheric chemist, in developing Continuous Flow Isotope-Ratio methods (e.g., Funk et al., 2004. In our Hg research we collaborate with Dr. Sanudo (see above) a geochemist specializing in ultra-clean techniques and ICPMS. We are also involved in an effort to develop positron emission tomography (PET) scanning to understand patterns of carbon and water allocation in plants in collaboration with an analytical chemist, Rich Ferrieri.We are using the capabilities of recently developed instruments at Brookhaven National Lab to measure in vivo movements of labeled carbon and water. These efforts are supported by NSF and DOE.

Revised by Manuel Lerdau,  mlerdau @ life.bio.sunysb.edu  1 November, 2004