Fertilizer and Global Change in the Nitrogen Cycle: Too Much of a Good Thing? will be the topic of a public lecture by Pam Matson, one of the world's leading ecologists, on Thursday, December 9, at 4 p.m. in the Thomas J. Dodd Research Center. The talk is part of the Edwin Way Teale Lecture Series on Nature and the Environment.

Matson is a MacArthur Fellow and a professor of geological and environmental sciences and international studies at Stanford University.

A biogeochemist, she has shown that serious negative global environmental changes result from changes in land use and the intensification of agriculture. Matson and a multidisciplinary team analyze the economic drivers and environmental consequences of land use decisions and seek alternative practices that are economically and environmentally viable.

"Human activities have dramatically altered the global cycle of nitrogen, with serious negative consequences for the environment," she says. "Through the use of industrial fertilizers, fossil fuel burning and the growth of nitrogen-fixing crops, humans have doubled the rate at which nitrogen becomes available for use by plants and animals in terrestrial ecosystems.

"While this increase in available nitrogen has contributed to the major increases in global food production over the last four decades, it also carries serious negative consequences for ecosystems and the environment."

In her talk, Matson will discuss the role that agriculture plays in these changes, drawing on research carried out in the United States and Mexico.

Matson is a member of the International Geosphere-Biosphere Programme, the National Research Council on Sustainable Development, the U.S. National Committee on Problems of the Environment (SCOPE), the American Academy of Arts and Sciences and numerous other national and international boards, and a prolific author of scientific articles and books.

The Edwin Way Teale Lecture Series on Nature and the Environment is intended to promote interdisciplinary and multidisciplinary thinking and action. Each year the series brings leading scholars and scientists to the University.

Carol Davidge