RIVERSIDE — William H. Schlesinger, a leading biogeochemist and the president of the Cary Institute of Ecosystem Studies, New York, will give a free, public lecture at the University of California, Riverside on Monday, Oct. 19, that focuses on the global nitrogen cycle — a biogeochemical cycle that describes the exchange of nitrogen between living organisms and the nonliving world.

His hour-long lecture, “Chasing the Atoms in the Global Nitrogen Cycle,” is at 4:10 p.m in the Statistics Building, Room B650.

Nitrogen, the most abundant element in the atmosphere, is essential for many biological processes and to all life, its availability playing a crucial role in the organization and functioning of the world’s ecosystems.

In his lecture, Schlesinger will attempt to estimate the fates of human-derived nitrogen on land — how much is moving through the atmosphere, to rivers, to groundwater and why this excess nitrogen is causing problems.

"Humans have more than doubled the inputs of nitrogen to the land surface, largely through the production of fertilizer," he said. "Unfortunately, we have very little idea of where all that nitrogen is going."

During his visit to campus, Schlesinger also will discuss the importance of building an ecosystem program at UC Riverside.

Ecosystem ecology is the study of flows of materials and energy between organisms and the environment. It includes large scale global issues such as climate change, nitrogen deposition and invasive species.

"Solving these problems requires a multidisciplinary effort by teams of researchers, with funding from federal agencies such as the National Science Foundation or the Department of Energy," said Edith Allen, an extension specialist and a professor of plant ecology in UC Riverside's Department of Botany and Plant Sciences who has led the effort to build an ecosystem program on campus. "UCR is poised to become nationally recognized in ecosystem ecology as critical areas in our program are filled."

Before joining the Cary Institute of Ecosystem Studies, Schlesinger served in a dual capacity at Duke University, as both the James B. Duke Professor of Biogeochemistry and dean of the Nicholas School of the Environment and Earth Sciences.

A graduate of Dartmouth College (A.B.) and Cornell University (Ph.D.), Schlesinger has been investigating the link between environmental chemistry and global climate change for more than 30 years. His recent work focuses on understanding how trees and soil influence atmospheric carbon dioxide levels.

Schlesinger is the author or coauthor of more than 180 scientific papers. His textbook "Biogeochemistry: An analysis of climate change" is widely taught at the university level. Findings from his research have been featured on NOVA, CNN, NPR and in the pages of Discover, National Geographic, the New York Times and Scientific American.

His distinctions include elected membership in both the National Academy of Sciences and the American Academy of Arts and Sciences. He is a board member of the Natural Resources Defense Council, a fellow of the American Geophysical Union and a past president of the Ecological Society of America.

Schlesinger is committed to bridging the divide between science and policy. He has testified before U.S. House and Senate Committees on a range of environmental issues, including desert habitat preservation, global climate change, and, most recently, carbon sequestration. Currently, he serves on the boards of the Doris Duke Charitable Foundation, the Southern Environmental Law Center and Terrapass LLC.

For more information about his talk, call (951) 827-2123 or e-mail edith.allen@ucr.edu.

The University of California, Riverside is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UC Riverside's enrollment of about 18,000 is expected to grow to 21,000 students by 2020. The campus is planning a medical school and has reached the heart of the Coachella Valley by way of the UC Riverside Palm Desert Graduate Center. The campus has an annual statewide economic impact of more than $1 billion.