For pioneering research in disturbance and landscape ecology and in modeling of land-use change with its implications for global changes, which have influenced environmental decision making on a worldwide scale.
For distinguished research on the air/surface exchange of atmospheric trace gases and particles and their interactions with the Earth's biogeochemical cycles, and for pioneering developments in atmospheric sampling methodologies with special emphasis on the global mercury cycle.
For theoretical research on the electronic and vibronic structures and optical properties of defects in ionic crystals, and for work at the forefront of the rapidly developing field of laser annealing of semiconductors, leading to advances in the photovoltaic conversion of solar energy.
For original studies of the genetic effects of radiation in mammals. A world authority on mammalian mutagenesis, he and co-workers provided the experimental basis for estimating the genetic hazards of radiation to man and for the corresponding recommendations of national and international standards bodies