Global biogeochemical cycles in the climate system / Глобальная биогеохимия. Циклы в климатической системе

In the late 20 th century, biogeochemistry emerged as a new discipline in which the biological, physical, and human sciences collaborate (CGCR, 1999; Schlesinger, 1997). Biological, because the chemical cycles of the planet are mediated by life (Table 1). Physical, because of the strong coupling between climate and atmospheric composition so evident in the glacial-interglacial record of the ice cores (Fig. 1). And, human, because of the massive human disruption of the planet's carbon and nitrogen cycles by fossil fuel burning (which produces CO2 and a range of volatile nitrogen compounds) (Fig. 2). 

From the three figures, one gets an overview of the way in which the field of biogeochemistry has emerged. The evidence for the importance of biology in the composition of the atmosphere (Fig. 2) was deduced from geochemical measurements of air enabled by advances in analytical technology. The chemistry of the atmosphere and the discipline of atmospheric chemistry provided a view of the biosphere not accessible from "within" the discipline. The atmosphere reflects biotic processes operating over "deep" time as well as processes operating on rapid time scales (especially with respect to the oxidized N species). Some compounds, especially the hydrocarbons, may reflect plant-insect coevolution, and so to understand the atmosphere requires a deep understanding of biology. When insights into atmospheric chemistry were combined with emerging ecosystem studies of nitrogen and other elements (e.g., Vitousek and Reiners, 1977), a paradigm emerged that enriched both ecology and geophysics (Andreae and Schimel, 1989) <...>