Under new editorial direction, Advances in Agronomy both continues its long tradition and expands to include innovative methods and technologies. Leading international scientists cover topics in plant and soil sciences, biotechnology, terrestrial ecosystems, and environmental concerns. The second volume under new editorial direction, Advances in Agronomy, Volume 47 focuses on environmental quality and biotechnology. Four articles on soil science cover acid deposition, chemical transport, and surface complexation. Two articles on crop science survey variety fingerprinting and corn evolution. This and related volumes will be of interest to agronomists and biotechnologists in academe, industry, and government.