ica, I considered myself an old hand: when I started to study the
environment of the North Bohemian region in 1963, the ecosystemic
changes and health effects result- ing from extremely high
concentrations and deposition of sulfurous and nitrogenous air
pollutants and particulate matter could not be ignored. When I returned
to the area in 1966 to work there for nearly three years as a consultant
in energy and environmental affairs, I came to realize the difficulties
of efficiently controlling the problem. Hiking on the crest of the Ore
Mountains overlooking the valley, I saw much destruction and degradation
of coniferous plantings-but I was also repeatedly surprised by the
contrast of the withering tops and stunted dried-out growth of spruces
and firs with the magnificent beech trees and the healthy understory of
shrubs and wild flowers. I recall this impressive lesson of ecosystemic
vulnerability and resistance every time I read sweeping generalizations
about the environmental effects of acid deposition. At the same time, in
the second half of the 1960s, I was introduced by a friend, an engineer
working in analytical chemistry and biochemistry, to some of the
mysteries of enzymes; this led me to nitrogenase, one of the most
incredible sub- stances on this planet, and to an interest in various
aspects of the nitrogen cycle, which was further strengthened by my
later work on the energy cost of crop production, involving inevitable
comparisons between natural nitrogen fixation and Haber-Bosch ammonia
synthesis.