Geochemistry and the Biosphere. Vladimir I. Vernadsky
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volumes, following are some examples of points that I had to ponder (others are presented as footnotes):
Vernadsky’s thoughts about Earth’s history might have been radically changed if he had known about the oxygen revolution that is now thought to have occurred about two billion years ago in the Precambrian. Actually, he came very close to discovering it himself (in certain iron rocks). Again and again, he states that the Earth has remained essentially the same since its formation. This cannot be the case if oxygen built up to a high level during Earth’s history – such a build-up would change many aspects of geochemistry, not to mention the functioning of the biosphere (which surely was responsible for the oxygen build-up; Vernadsky often mentions that nearly all atmospheric oxygen can only be the product of life, of photosynthesis).
Along with other scientists of his time, Vernadsky assumed that, on an area basis, ocean plankton carried on about the same photosynthesis as land plants. Since the area of the ocean is about twice that of the land, they assumed that, in total, ocean plankton photosynthesize about twice as much as do land plants. We now know that most of the oceans are “nutrient deserts,” limited in life by the absence of certain mineral nutrients, especially iron. We think that land plants account for about twice as much photosynthesis as do ocean plankton.
There is a minor matter that struck me as a plant physiologist and would-be ecologist: Vernadsky states that the total area of leaves above a given land area is about 100 times that of the area below (but also counting photosynthesizing organisms on the soil). This “leaf-area index” has now been measured many times and proves to vary from about 1 (deserts) to 11 (tropical rain forests), with a few instances going to 38 (boreal conifers). Averages are about 5 to 8 (typical of deciduous forests).
Perhaps the field that Vernadsky least understood was biochemistry. He never mentions enzymes or genes, and even in his time, the importance of enzymes was becoming known (beginning near the end of the nineteenth century). At one point he even seems to take issue with the importance of proteins (all enzymes are proteins), implying that the concept of “living proteins” is nonsense. By now, enzymes and the genes that control their syntheses are thought to be paramount in life function. Vernadsky does mention that proteins are important, but he never mentions enzymes.
My thoughts and annotations are limited by my knowledge, but an earlier edition of The Biosphere was annotated extensively by Mark A. S. McMenamin.1 I found the annotations in that edition to be most interesting and valuable. Clearly, McMenamin’s knowledge in this field goes well beyond my own.
Both Vernadsky and the translator use some words that might not be familiar to those of us who are not geologists. After much study, I added some footnotes to explain some of these terms. One of them really provided a trap for me: Vernadsky repeatedly speaks of processes, organisms, and chemicals occurring in the stratisphere. At first, being a poor speller, I tried to visualize these things taking place high in the stratosphere, but that seemed increasingly preposterous. I went to the dictionaries but could never find stratisphere. Considering related terms as well as the context in which Vernadsky used the term, it finally became clear that he was talking about the “sphere” made up of Earth’s strata – the sphere of sedimentary rocks. The term is so insidious that I would have changed it if I could have thought of a suitable synonym, but terms such as sedimentaryrockosphere just wouldn’t do, so I left stratisphere as Vernadsky used it. Be aware!
All these problems are completely secondary to Vernadsky’s main theme: The biosphere is a powerful geological force that has transformed this planet and its geochemistry in a most spectacular way. I think this must have been apparent to many of his contemporaries (e.g., the science of ecology was vibrant by his time), but there is probably no other writing produced during that time that pulls it all together as well as these two volumes do.
In his introduction, Alexander Yanshin tells how Vernadsky was fascinated by the world around him from a very early age – how he read avidly in several languages everything that he could lay hands on in his father’s large library. Thus his mind accumulated a vast amount of knowledge about the science of his time, as well as the centuries preceding.
Over the years he developed many suitable characteristics for a life of science. He was able to pull together and organize an incredible amount of information and then to apply powers of analysis that were truly phenomenal. As we might well expect, these personality talents of a great scientist led to some highly unique views, relating both to science and how it works as well as to the details of geochemistry and the biosphere. All of this becomes clear in these two volumes.
We see these ideas from the standpoint of a Russian scientist who lived both in his native land and abroad during the period of the Russian Revolution and the Stalin era – which he never mentions in these writings! That in itself provides a perceptive insight into the Russian scientific mind: Although Vernadsky was active in the politics of his day, he leaves all that behind in these writings as he concentrates on questions of the biosphere and Earth’s geochemistry.
You’ll see that Vernadsky had a tremendous drive, not only to understand the natural world, but to know those who preceded him in seeking that understanding. As he cites and describes the work of hundreds of scientists who came before him, we gain a very broad view of how our modern science has developed.
Today, many scholars who write textbooks or review a particular topic confine their interests to work done in the preceding few years, or at most, few decades. In contrast, as a historian of science, Vernadsky’s interests stretch back for a few centuries (especially the eighteenth and nineteenth centuries), revealing that the twentieth century (and now the twenty-first) are not alone in producing good and valid facts and ideas. Furthermore, his admiration for those scientists of previous centuries shines through strongly. Many of us might dismiss the scientists of the age of phlogiston or a geocentric universe, or those who talked about biology and the biosphere (not yet even named!) before the importance of the cell was realized, but Vernadsky could appreciate the creativity and power of their minds and focus on the penetrating ideas that others had overlooked, bringing them to our attention and pointing out that they are reflected in our current thoughts about natural history. One notes Vernadsky’s love of history again and again in these writings, but especially in the second of his Essays on Geochemistry, in which he reviews the development of his science.
Vernadsky was a philosopher of science as well as a scientist who was concerned with how the universe functions. Some of his philosophical ideas struck me as rather strange (especially in The Biosphere) until I was gradually able to fit them into an overall context of his approach to science. At one point he rails against the reliance on mere hypotheses, insisting that the only suitable method for a scientist is the (Baconian) system of accumulating facts until empirical generalizations, as he calls them, become apparent from the data. Such hypotheses as those relating to the origin of life were “philosophical and religious” hangovers, hardly worthy of true science.
A prime example of an empirical generalization is the Periodic Table of the Elements. When enough was known about the valences and atomic masses of enough elements, it became apparent to his professor, Mendeleyev, that they obeyed a “Periodic Law,” and this law was so powerful that it predicted the existence of many more elements. These predictions were fulfilled to a great extent in Vernadsky’s time and continue right up to our time. It is noteworthy that Vernadsky was well acquainted with developing chemical theory, based on the atomic models that were only being established with the formation of quantum mechanics; indeed, most of that new science was being worked out during the time that Vernadsky was writing The Biosphere.
Although he disparages hypotheses at some points, it is clear from other discussions that he agrees with the modern scientific approach of formulating hypotheses that can be tested by suitable observations and/or experiments. Vernadsky’s way of developing empirical generalizations is essentially an inductive method, which is at the heart of most of our modern science. (Since it is impossible to observe every instance of some phenomenon, we must sample the phenomenon and then generalize that our sample is typical of the phenomenon in general. This is induction, but Vernadsky sometimes applies the term deduction to this process. Deduction deduces specific ideas from general laws.)
Vernadsky held to a substantive uniformitarianism, or at