6. INFLUENCE OF ORGANISMS

From Lavoisier (1790) we owe the rule of the indestructability of matter: “rien ne se perd, rien ne se crée”. Robert Mayer (1842) has created its analogue in energetics: the rule of the indestructibility of energy, “das Gesetz der Erhältung der Kraft”. Both rules have become to one since Einstein’s demonstration of the identity of matter and energy.

Now Clausius formulated the second law of thermodynamics in 1855. This law states that the diffuse form of heat, the entropy interacts at the expense of the useful work performed during any energy transaction. Bolzmann recognises this increase of entropy as a general trend in nature and predicts a “Wärmetod” for the Kosmos.¹

We are interested in the material counterpart of the second law of thermodynamics. Analogous to an increase in diffuse, non-utilisable energy, the entropy, there should be, during a chemical or mechanical reaction an increase in the material dispersion of the system. This material dispersion we call dissipation. At another place in this book, we shall revert to this problem (see Baas Becking, Proc. Roy. Ac., 1942 and Burgers, Entropie en Levensverschijnselen, Verh. Ak., 1943) when we deal with the influence of forces both animate and intelligent.² The workings of man as shaper of the environment. Here it should suffice to state the influence of organisms upon the dissipation. Organisms are able to concentrate (geochemically) rare elements. Organisms are also able to exclude chemical compounds from their internal milieu. But the effect of the element upon the organism does not need to go parallel to its concentration. Now in squandering our heritage we have sown that which we cannot harvest. We have dissipated, minutely dispersed, a number of elements, that actually belong in earth’s molten core, or in the calx surrounding it. We owe it to living things that these are brought back to us concentrated by the anti-dissipatory action of living matter. Of course, care should be taken not to squander at a rate greater than accumulation and concentration. And the squandering may be not only our doing, and the concentration not only a biological process, at that. Thus, both animate and inanimate seem to collaborate here.³

(Baas Becking, 1942a; see also Noddack, 1942, Naturwiss.),⁴ V.M. Goldschmidt (1923).

When we plot the log concentration of the bioelement within in the organism against the logarithm of the concentration of these elements in the earth crust, we find little correlation (Fig. 6.1). If we plot against the concentration in the hydrosphere, we see only 2 elements, hydrogen and oxygen on the diagonal, they are neither concentrated or dissipated. This is rather evident, in as much as organisms consist for such a large part of water. But the organism has apparently created its own world, and the composition of this world, is quite different from that of its surroundings. We have seen in Section 1 how preponderant the elements O, Al, Fe, Si are, still, the organism has to build something quite different, at least quantitatively different.

Carbon is, of course, preponderant, it has to be concentrated from 0.002% in the hydrosphere to ±10% in living matter! This concentration is brought about by the carbon dioxide assimilation of the green plant and the subsequent dehydration of the glucose formed to products as cellulose. The dissipation of the carbon is never so great as the concentration, or part of it, formerly was.

Iron is, in seawater only present in a few γ/cm² (as Cooper (1935) showed), as the fluoride.⁵ How the intake and concentration take place we do not know. Inorganic iron is present in plants (Molisch). Most of it is bound to porphines and the like. The re-dissipation is presumably complete.

The most interesting case of concentration we find in the iodine. In freshwater it is hardly present. Still all organisms contain it, and some (mammals, sponges, algae) in appreciable quantities. We only know it in organic compounds with the organisms, such as di-iodothyrosines or thyroxine (Bayer) [small drawing of the molecule structure]

In freshwater and in seawater a veritable minimum factor. Enters the plant as acid phosphate ion (v.d. Honert),⁶ and is built in in various compounds (lecithinoids, Cu phosphate and apatite). It cannot be induced by living cells, although there are, perhaps, bacteria that may perform this feat.

Toxic when present in more than a few γ/cm² in the milieu. Enormously concentrated and built in the structure of bone and tooth, in the marine organisms more than in land inhabiting organisms. Its influence in plants to most well known.

The inspection of the mineral analysis of ore, or a few groups of organisms, is never sufficient to obtain an idea about the significance of such minerals. Notably this is the case with Na and Cl. We know that they are useful things in the external milieu, as sodium and the most abundant of the earth alkalis, such as Ca and Mg. We know that the formation of HCl plays a role in the digestion in higher animals, and that NaCl is a regular component of the body fluids. Also, its decrease goes parallel with certain pathological phenomenon. Still, NaCl causes in plants curious aberrations (succulence) which are induced hereditarily on certain species, but make us suspect that the role of Na and Cl is not as universal as we thought before.

There is a tenfold decrease at least from seawater concentrations to body fluid. As Kuenen has shown even halophyte organisms like Artemia have quite diluted body fluids.⁷ Ancel Keys demonstrated the presence of a NaCl secretory gland in the cell.⁸ Kidney function also performs work to concentrate excretion NaCl and so to dissipate it (Nernst RT log C₁/C₂).

In organisms, in certain enzymes, in chlorophyll, and in the aleurone protein. Necessary apparently in very small quantities, while present in seawater in high concentrations. The method of dissipation is totally unknown. How its permeation as against the necessary Ca is regulated, remains a mystery.

Excretion of chlorides is known to occur in succulents, as well as in other plant families. This should elaborate the statement made above under sodium. Its position in the Hofmeister (1888) series, (or better, lyotropic permeability series) might account for its lack of accumulation within the cell.⁹

Although hydrogen and oxygen are intensely used in the cell, the amount of these elements taken up in metabolic activity is so small as compared with the total amount of cellular water that it may conveniently be neglected. Even all of the hydrogen and oxygen fixed in organic compounds is out small percentage of the total cell weight.

A plant may grow, constantly accumulating and concentrating atmospheric carbon (Fig. 6.2). It grows from I to M, and the dissipation of the carbon decreases, perhaps following some such curve as given in the diagram. At M it dies and decays or is eaten, the dissipation of its carbon increases, but never to the level as where it comes from. There is a gain, a net gain in concentration, incarcerated in the bodies of the organisms which fed upon the original plant and also incorporated in fossilising carbonaceous material. In the cycle of the carbon there is no complete repetition, part of it is held back. In the case of the iodine, we meet the same thing, although the factor ‘fossilification’ is absent. But still the concentration in an original organism I-M may partly be maintained by organisms feeding upon this initial organism (level c in the figure). The ‘fossil’ concentration becomes again quite important in such elements as phosphorus while in others, like nitrogen, it is neglectable (only Chilean nitrate and guano).

It would be interesting and worthwhile to investigate in detail the concentration and dissipation of a number of bioelements. As we shall see later, ‘waste’ is one of our chief problems. The concept of dissipation is closely allied to this problem. In this section we shall further deal with the influence of organisms upon the inanimate world. It will be seen that the influence is profound and in certain cases, as in the atmosphere, dictatorial. Biochemically, this influence may be ultimately traced to the accumulation, the concentration power of the living cell. To elaborate upon the mechanism of this concentration, intrability and permeability in general, is a task for physiology and being outside the scope of this essay.

People in a crowded room not only change the CO₂ tension, but also the temperature and the vapour pressure. Soon we are right outside the ‘area of well being’ and we become too dazed even to speculate upon the influence of organisms upon the physical milieu. We are struck, when aboard a steamer, or walking along the beach, or in the forest, by the wonderful phenomena of bioluminescence. From the example given it would appear that organisms exert a marked influence upon the physical milieu. But this influence is local, and, what is more important goes with very little energy exchange. The biophysical phenomena, while curious, lack the great geological importance which is particular to many other biological phenomena.

Description of the wonderful thermostat which is the warm blooded animal, falls outside the scope of this essay. Animals with imperfect eurythermy (duck bill, insectivores, bats and rodents) show real hibernation.¹⁰ During hibernation they are poikilothermic after awaking a bat may raise its temperature by 25 °C in less than a minute. It should be remarked, however, that even cold blooded animals may raise the temperature of the environment by several degrees. Pythons are said to incubate their eggs. The heat production by microbes is a well known phenomenon and is dealt with more fully in Section 5.4. Animals make use of this heat production! The mallard hen, Megapodiidae,¹¹ occurring in Australia and islands of the Pacific, lays her eggs in mounds made of rotting leaves. The cobra is said to do the same. About the regulation of temperature inside a beehive (see Shelford, 1929, p. 322). Higher plants may produce heat in the floral organ, raising the temperature as high as 48 °C. (Nymphaeacea, Aracea, Aristolochiacea). In Sauromatumvenosum (Aracea), van Herk (1937) found enormous consumption of sugar under the influence of the yellow respiration enzymes.¹² Post-mortal (necrobiotic) changes in leaves (tobacco) may give rise to temperatures up to 50 °C. According to Schwarz and Laupper (1922) the self combustion of hay is due to a chemical reaction catalysed by iron. According to Mach (1900a and b) this is a (pyrophoric iron) in probably localised in the plastid.¹³

Certain marine bacteria (B. phosphoreum, V. indicus)¹⁴ various Hymenomycetae (Mycena, Xylaria),¹⁵ lampyrid beetles, a crustacean (Cypridina)¹⁶, jellyfish, and gastropods are able to radiate a blue or green, perfectly cold light. The mechanic of this emission was first studied by R. Dubois (1886 and 1892) and later by E.N. Harvey and co-workers (1928) .¹⁷ Pierantoni (1921) claims that light emission of higher animals and worms takes place by symbiotic bacteria.¹⁸ In the last decade the late L.S. Ornstein and A.J. Kluyver and co-workers have been able to elucidate the mechanism of light emission further.¹⁹ Already, Dubois (1886) assumed the presence of a substance luciferin and atmospheric oxygen changed into oxyluciferin. Now Kluyver has been able, by a very ingenious method, to obtain the spectrum of bacterial luciferin and to find organic, luminescent compounds, which show similar spectra (oxychinones ?).²⁰

50 millivolt is usually the potential drop near the other phase of a living cell. Certain specialised cells of specialised tissues of tropical fishes (electric eel, and rays [order Torpediniformes]) are able to generate currents of 40 – 60 V. About the mechanism of the process the literature is still obscure.

At another place (Section 3.6.11) we shall deal with the influence of organisms upon atmospheric humidity. Where the evaporating capacity of bare soil and vegetation often greatly differ, it is obvious that organisms contribute greatly to the atmosphere and influence its humidity. The effect has, up till now, been studied little, although much speculation exists upon this, and allied matter.

While the changes caused by organisms in the chemical milieu are of enormous geological importance the microbes, the plants and the animals leave no imprint upon the physical milieu. The changes here are interesting, they are measurable, they are manifold, but they are of no further geobiological consequence. Of course, the influence upon the cystic movements of water is enormous, and requires special treatment at another place.

Already, Sachs (1865) could demonstrate the excretion of acids (he ascribed the action to CO₂ of plant roots, which he grew between marble slabs, with the resulting corrosion of the calcite).²² It is known that spectacle lenses, window glass and photographic plates are attacked, in the tropics, by a silica dissolving fungus, an organism, therefore, that is able to secrete alkali. The chemical influence of organisms is manifold, and only a few instances may be mentioned.

Respiration in an aqueous milieu, by liberation of CO₂, will acidify the water as H₂CO₃ is formed which has a dissociation constant of 4.7 × 10^-7. According to some, only part of the CO₂ forms, with H₂O, H₂CO₃. According to others the acid present is not H₂CO₃ but either a brine acid C(OH)₄. In any case the acid seems too weak for H₂CO₃!

Photosynthesis, by withdrawal of CO₂ will make the water more alkaline. The water, which is much buffered to the acid side, but very weakly buffered to the alkaline side will suffer, in 1 litre, a large starfish for hours without marked drop in the pH. A few fragments of the alga Ulva, in the light, will cause the pH to rise within a few hours from 8.1 - 9.2.

In the section on metabolism many examples of the excretion of important organic compounds by plants may be given. Here we call attention to substances which may poison the milieu, for competition. We mention here the well known penicillin of Raistrick²³ and the remarkable, amine-like compound excreted by the alga Chara and the anti-germination substances discovered by Troschel (1854) as secreted by many seeds of economic plants. Sepia is a remarkable camouflage substance secreted by Loligo. [in margin: Tonna galea, H₂SO₄,²⁴ centipede, HCN, beetles, iodine!]

Baumann and Gully (1910) claim the following origin for the acid in Sphagnum bog.²⁵ The bog being ombrogenic (fed by rainwater only) mineral content of the water will be low. The cations in the rainwater (mainly Na) are absorbed in the cell walls of the Sphagnum and exchanged for H⁺. Assuming a plausible value for NaCl in rainwater, ±30 micromolar we might expect the equivalent of 0.5 × 10^-3 N Na⁺ in H ⁺ions, corresponding to a pH of 4 - 0.7 = 3.3. This may be actually a pH observed in a fen moor! Baas Becking and Nicolai (1934) and Vaas repeated the experiments under a variety of conditions and confirmed, on the whole, the above hypothesis.²⁶ Activity of so called humic acid (Odén, 1922), CO₂, iron salts or organic acids they were able to exclude. As the only anions in the rainwater were Cl^- and SO₄^2- is quantitatively reduced in a Sphagnum bog to H₂S the acid present should be hydrochloric acid.

Thompson, Lorah and Rigg (1927) were able to corroborate these findings for Canadian peat bogs. We shall have occasion to revert to this problem again in Section 9. Suffice is to state that agar treated with HCl to remove the Ca, and washed until neutral, will become acid again when watered with dilute NaCl (H. Bungenberg de Jong). Roots have been shown (by means of radioactive K) (Schuffelen and Loosjes, 1942 a and b) (see Section 6.3, Periodic Changes in Chemical Milieu), to exchange K between internal and external milieu. Both processes are of almost equal intensity. Here, apart from potential and membrane effects, metabolism plays a large role.

Arens (1934) and his pupils (Lausberg, 1935) have shown that leaves excrete large quantities of salt (leaf weight per season) chiefly potassium acid phosphate.²⁷ When the leaves (tobacco) are washed by rain these salts will become available to the plant again. The amount excreted in this way may mean more than ½ of the weight of the leaf per season. It is, therefore, not indifferent whether tobacco is harvested before or after rain!

“L’influence des êtres infiniment petits est infiniment grande.” [Louis Pasteur]

The more permanent changes caused by organisms result from interference with the biological cycle. By suppression or inhibition of one or more chain processes inside a cycle, compounds may accumulate. They may be changed by later geochemical or geological forces, but the rhythm is interfered with. Only in special instances organic material may accumulate, usually the changes in the chemical environment only show in the mineral realm, although they are caused by biological agents. We shall mention:

An incandescent earth could hardly show any free oxygen in the atmosphere in contact with the lithosphere. The formation of oxides would consume the oxygen. V.H. Goldschmidt has called attention to this fact in 1923 and has elaborated the hypothesis that the ±21% oxygen in our atmosphere is entirely derived by the biological reduction of carbon dioxide, resulting in a gradual increase of the oxygen. Goldschmidt assumes a small initial amount of oxygen without which “life could not start.”⁴⁰ Biologically, this assumption seems unnecessary. We know, and have treated these cases in this book, of many organisms which are utterly autotrophic and still able to persist without oxygen, if only free loosely bound hydrogen be available in the milieu. Goldschmidt gives, moreover, a geochemical calculation which should account, quantitatively, for the increase in oxygen in the atmosphere. His reasoning is as follows.

The oxygen liberated in photosynthesis, may be used for the oxidation of organic material. As the respiratory quotient of this process, like that of photosynthesis, averages around the same numbers (1.00), this process contributes equally to the debt and credit side of the balance. Plants have to reduce the oxidised compounds NO₃-NH₃, SO₄-H₂S before animals can make use of them. This harks back, to the original earth, where everything was always honest! See also v. Tongeren. Chem. Weekbl. 32, 304 (1935).⁴¹

1. Part of the organic matter remains as humus or as caustobiolith. There should be a relation between the amount of oxygen liberated. [in the margin: This consumption has to be estimated lower, however, as the oxygen of sulphates becomes available, by its reduction, for the oxidation of other compounds, both inorganic and organic, such as H and organic acids. See for older literature, Clarke (1916), (Kelvin), Lénicque.]⁴²

2. Weathering of volcanic minerals, by which bivalent iron, manganese and pyritic sulphur are oxidised will consume a certain amount of oxygen.

3. Extracting consumption from production should give the amount of oxygen present in the atmosphere. This amounts to 0.232 kg/cm² earth surface. Now the amount sub 2 [see above = weathering of volcanic minerals] (oxidation of Fe²⁺, Mn²⁺, S^2-) may be estimated as 0.2-0.5 kg/cm². Therefore, the amount given as 1a should be 0.2-0.5 + 0.212 = 0.4-0.7 kg/cm², corresponding to 12/32 × 0.5 – 0.8 or 0.18 – 0.29 kg/cm² fossil carbon. This should be divided over 170 kg/cm² sedimentary rock yielding an average carbon percentage in the rock of 0.17%. This seems to be in good agreement with the analytical data.

It seems to the author, however, that not only the reduction of the carbon dioxide, but also other inorganic reductions may ultimately give rise to oxygen. Even if this is not atmospheric oxygen it should influence the amount of 2 [= weathering of volcanic minerals] as the sulphate reduction is one of the most intense geobiological processes. Still, Goldschmidt’s concept elucidates much that remains mysterious. Goldschmidt has, moreover, shown that, in order to satisfy the basic oxides originated by weathering ±6.5 kg/cm² CO₂ are necessary. In order to satisfy photosynthesis, we have to increase this value to 7.5 kg/cm² CO₂. This enormous amount may only be supplied by volcanic action.

In 1937, at a meeting of the Royal Netherlands Academy the author called attention to the great influence of Goldschmidt’s concept on biology.⁴³ The earth is becoming increasingly aerobic and in as much as differentiation in organisms is caused by a large number of sugar metabolites, the formation and existence of which depends, to a large extend, in adequate redox potential (see also Ruhland, 1938).⁴⁴ It seems obvious that a region where differentiation is prepared (meristems of shoots and roots) should be kept at a certain maximum oxygen potential, above which the valuable ergones should be irretrievably oxidised. Meristems are, therefore protected. In buds by waxed or varnished scales. In Aesculus dwarfing seems to go parallel with the structure of the bud. Furthermore, plants related to those that, according to Goldschmidt should have lived, under considerably reduced oxygen pressure, in the Carboniferous era, like horse tails and Lycopods, show typically exposed, vegetation cones. In the Carboniferous epoch, about 500 million years ago, the atmospheric oxygen might have amounted to ±15% instead of 21% assuming a proportional increase of oxygen contents since the inception of a cooled earth about 2000 million years ago.

When dealing with the symbiosis problem of Ardisia, we have dealt with this matter (see Section 7.5.2).⁴⁵ Here we have a plant that apparently obtained ‘too much’ oxygen from our normal atmosphere. It seems not too far fetched to comment the enormous development of Lycopods and Equisetes (the poor remnants of which are now dragging out a precarious existence) with the favourable oxygen tension existing in those days. The problem seems capable of experimental approach. The influence of vegetation upon rainfall will be dealt with in Section 8 under deforestation.

Very important is the nitrogen fixation, apart from certain bluegreens (Galestin, 1933),⁴⁶ we have the aerobic Azotobacter, the symbiotic Radiobacter and the anaerobe Closteridiumpasteurianum. All these forms need probably molybdenum. According to Virtanen (1930) they first form hydroxylamine, later NH₃.⁴⁷ The efficiency, as compared to Haber process, seems to be rather high (Baas Becking and Parks, 1925). See survey by Löhnis, (1943, Vakbladvoor Biologen). ⁴⁸

Volcanic activity might cause high CO₂ content of the atmosphere. The influence of this high CO₂ tension in volcanic valleys on vegetation has not been investigated, as far as the author is aware. Von Faber investigated the plants that occur near solfataras on Javanese volcanoes - plants that are probably to a certain degree immune for SO₂ vapour.⁴⁹ We know from industrial damage caused by flume gases of smelters that SO₂ exerts a deleterious effect on many plants, especially on the photosynthetic apparatus. Apparently the SO₂ combines with chlorophyll. Large colonies of man (cities) cause a marked pollution of the atmosphere, especially around industrial areas: NH₃, toluene, benzene etc. are often present. Jacq has called attention to the fact that most species of Lichens seem to stream the town.⁵⁰ They appear as “père du organisms.” The author has checked this idea in several waters in the vicinity of Rotterdam. Further anthropic influences shall be dealt with in Section 8 on Man.

[Baas Becking referred to Section 5.7.6.]

1. Photosynthesis and respiration. During photosynthesis alkalinity will increase until Ca, and later Mg, precipitate. Also, HCO₃^- decreases at the expense of CO₃^2- (K in Fig. 6.3 and arrow from A running N-E). Respiration causes the opposite changes in acidity, increase in Ca and Mg until dissolved.

2. Sulphate reduction and sulphide oxidation during sulphate reduction the oxygen disappears, the alkalinity increases (A in Fig. 6.3). The opposite takes place when sulphide is oxidised, water is created, oxygen tension increases, and acidity increases (see Section 9.6).

3. The origin of the acidity in bog water will be treated in Section 9, see also Section 3.7. The oxidation of sulphur by the formation of sulphuric acid, and acid ferrisulphate causes oxidation sometimes higher than 1N H₂SO₄ (pH = 0). These oxidations are obtained by means of a ‘living catalyst’ Thiobacillus thiooxidans (Waksman and Joffe, 1922).

[in the margin:]

[4]. Denitrification and oxidations.

[5.] Cellular fermentation sequences CaCO₃etc.

See also Figure 5.14.

F.E. Hecht: “Der Verbleib der Organischen Substanz bei Meerischer Einbettung.” Senckenbergiana 15 (1933, p. 165-249). Chemical decomposition of animals. Krejci-Graf, K., Oelgeologische Thesen, Berlin (1931).⁵¹

Petroleum is of biological origin (optimal activity, substance like chlorophyll and haemoglobin). Petroleum originated from an original bitumen, probably anaerobically (under H₂S?), probably marine, diatoms, benthos, fishes, coproliths? (Hecht).⁵² Hyles obtained oil by distillation of algae. Thayer tied fatty acids R-COOH to decarboxylation, he obtained methane in the whole series up to inorganic acid.⁵³ Frank found no oil in recent sediments.⁵⁴ Adipose is only slightly changed animal fat. It is probable that oil originated in alkaline milieu. In 10 years, fat of a shark not materially changed olive glycerol. From diatom oil Hashimoto a whole bouquet of sterols. But origin of oil remained as obscure as ever.⁵⁵

Glucose is the mother substance of all caustobiolith formations. There is a road from glucose to fatty substances which according to Haehn and Kintoff (1923 and 1924),⁵⁶ originates from lower fatty acids by unsaturation. It is possible that from the fatty materials the heterogenous mass known as “oil” arises (line 1 in Fig. 6.4). In this phase of carbonisation the carbon is still in the diamond grating (aliphatic). In anthracite and graphite we already find the typical graphite grating (laminar). In carbonisation the diamond grating is left for the graphite C, aromatic compounds have to be converted [?] before we reach the carbon. As line 2 in Figure 6.4 is more than a straight dehydration, hydrogenation also plays a role. Finally, caramelisation, as shown by Schweizer is nothing but the reversal of water from the sugar molecule, but rather none than in the formation of the cellular chain.⁵⁷ This should follow line 3. The series lignine → brown coal → cannel coal → anthracite is non-biological and takes place in an anaerobic, alkaline milieu, where most of the organic substances disappear by bacterial activities (eutrophic plankton). Fatty substances remain but there is not a shred of experimental evidence as to how oil originates from them. Caramelisation may take place in the presence of oxygen. It may be, in certain cases, a vital process (formation of phytomelanins). For nomenclature see Potonié (1910), Haquébard (1943).

While carbonisation to caramel or anthracite takes centuries to perform, caramelisation may proceed quite rapidly. De Vries has shown that the black ‘humic’ substance in ebony and in composite fruit (sunflower),⁵⁸ the so called phytomelanins are probably identical with caramelisation products of sugar. The carbon is, as micro X-ray by Mr. D. Krejer [=K. Kreji-Graf (1930)] showed, amorphous.

Here the possibility for participation of animal remains is much greater than in petroleum oil, as many fish remains are found in ichthyol and as, near Rancho La Bréa, California,⁶⁰ the excavated organisms are equally recognisable.

Chitin is found in trilobites, in all ‘closed universe’ (Section 7.9.2). Bacillus chitinovorus of Benecke (1905) seems to have little appetite!⁶¹Lignine is found in coal, in all fossil and subfossil pollen grains, thus enabling us to reconstruct the flora of glacial epochs. Chlorophyll was found by Treibs in petroleum.⁶²

[Baas Becking inserted in the paragraph Fig. 6.5, Table 6.2 and Fig. 6.6. These figures and Plate 3.1 in Section 3.5.15, give in more detail the changes in composition of the organic compounds during the processes of humification, caramelisation and carbonisation. In the figures Baas Becking referred to Curt Enders.⁶³]

[Baas Becking made the following additional remarks in Fig. 6.6.]

Enders (1943) assumes methylglyoxaline (13) to play a role! This is very probable as carbonisation (A) and caramelisation (B) both obviously start from cellulose. A by changing over the graphite lattice, B by dehydration (keeping the diamond lattice).

In Section 3.6, it has been stated that due to the low solubility product (10^-8) of CaCO₃ this substance should precipitate from seawater, were it not for its tendency to form oversaturation and colloidal solutions. The influence that makes CaCO₃ precipitate are;

1. Changes in the physical environment such as pressure and temperature, which change the solubility of the CaCO₃.

2. Changes in the chemical environment resulting in an increase of pH or [CO₃^2-] or both. Among the latter we will name:

   • a) Photosynthesis,

   • b) Internal deposition,

   • c) Secretion of alkali,

   • d) Photosynthesis will alter the carbon dioxide equilibrium in a water. It will decrease the [H₂CO₃] and [HCO₃^-] and cause therefore [CO₃^2-] to increase, with concomitant increase in pH. Baas Becking and Irving (1924) found, in Corallines, a preliminary increase in pH of seawater in the light (Fig. 6.7).⁶⁶

The entire excess base had been exhausted by internal deposition of CaCO₃ (in the light), which also takes place in the dark. 8 g algae deprived 10 litres of seawater of its entire excess base in 18 hours.⁶⁷ Shells, corals and the like also are able to deposit lime in the dark, probably by pH increase in the internal milieu. Hubert (1935) found that a water moss Fontinalis was able in the light, to increase the pH up to 10.⁶⁸ Close to the precipitation point of organic salts! The natural, original formation of dolomite needs not be diagenetic as assumed by most authors (Correns, 1939, pp. 200-202). Arisz claims that aquatics are able to secrete Ca(OH)₂ from one side of the leaf (Elodea, Valisneria).⁶⁹ The old controversy about the action of the Bacillus calcis of Drew (1914), which should be active in the deposition of lime near the Bahama’s,⁷⁰ has lost much of its sharpness since Bavendamm (1931) showed that in Tortugas lime deposition will take place everywhere bacteria excrete alkali (probably NH₃) into the outer milieu.⁷¹ The Pasteur Bacillusurea, which deoxidises urea according to

should be considered here; the more so as their milieu limits seem very wide.⁷² They are eurybionts [animal or plant organisms capable of surviving under substantial changes of environmental conditions] as far as salt tolerance is concerned (Hof, 1933).⁷³ For further considerations in relation to lime deposition see Section 6.6.5. The oversaturation of seawater in CaCO₃ and its increase with increasing temperature is described in Section 3.6.⁷⁴

Senckenbergiana, bd 11, p. 160 (Schwarz, 1929).⁷⁵

Lydites in deep sea radiolarite.⁷⁶ Flint is made out of sponge needles. Van Niel, Yellowstone, found travertine terraces probably from oversaturated SiO₂ solution. Silica precipitated by bluegreen algae through dehydration locally by photosynthesis, where water is absorbed. Rivers are under estimated in silica (See also 6.6, Sediments). Solubility function of pH. Certain plants accumulate silica, grasses and palms, often in stigmata, further Equisetes. In Bamboo often very porous connections of pumice-like consistency, entirely formed by opal (= colloidal amorphorous SiO₂), ‘tabashir’ (absorbs gases readily).⁷⁷

Except for P in magnetic rocks and such minerals, [apatite, wavellite, andalusite, chiastolite, dahllite, collophan, vivianite], all phosphate is of organic origin. Bones contain up to - -, guano - - -.⁷⁸ Phosphate ion may not be reduced by plant cells, although there are claims that the ‘will-o-the-wisp’,⁷⁹ the light over a marsh may be due to spontaneous combustion of PH₃, originated by reduction of a diphosphate. Arens and Lausberg found excretion, of K₂H₂PO₄ by leaves.⁸⁰ Van den Honert found H₂PO₄^- ion only P compound absorbed by super ion.

As iron is usually only very slightly soluble in a natural water it must be surmised that most of the biochemical reactions in which iron plays a role, it should be in colloidal solution. The sulphate reduction forms sulphide in which, above a pH = 5 forms black FeS with ferrous salts. This FeS is probably the greatest oxygen consumer in nature as its oxidation by Fe₂O₃ + H₂SO₄ requires 7 atoms of O per molecule of pyrite oxidised. Part of this process (FeS → S) is chemical, part (S → SO₄^2-) is biological (see Verhoop (1940), Section 7.9.4 and Section 6.5). Another chemical reaction is FeS + S with the formation of pyrite FeS₂. If marcasite is formed in this way is unknown. Vaas claims to have demonstrated an accelerating action of iron bacteria (Gallionella) upon the reaction Fe²⁺ → Fe³⁺ (see also Section 7.6.4). Fe₂ (SO₄)₃, and FeSO₄ also occur in nature where Thiobacteria and FeS react under the influence of oxygen.

Certain Halophytes (Salicicornia) resist to severe salt NaCl.⁸¹ According to Keys and Wilmer (1932), the eel has the power in a special gland to excrete NaCl.

May be Echinoderm coprolith, according to Galliher (1935 and 1939) it is formed from biotite.⁸²

Is bird excrement saturation young chalk.

[in margin: Correns (1939, pp. 218-235) claims that all gypsum is of marine origin. If S deposits are – biological – why should not CaSO₄.2H₂O originate from them?].

There is often considerable doubt as to the cause of a geochemical process. Let us consider, as an example, the organisms playing a role in the sulphur cycle. As described by Bunker (1936), Ellis, Bavendamm (1931 and 1932), and others. Here we have a number of chemical processes for which either a microbiological or a chemical cause has been ascribed. A detailed study of a number of these processes was performed by Verhoop (now G.J.A. Iterson Jr.) in her Leyden doctor’s thesis.⁸³ Natural black mud (finely divided FeS in clay) originated by biological sulphate reduction, oxidises at the air, according to

Aerobically, the sulphate originated is oxidised further to sulphate into sulphonic acid. Verhoop measured the oxidation of the pyrite (hydrotroilite) colourimetrically and found a steady acceleration of the process up to 100 °C, the Q₁₀ being in the neighbourhood of 2.0. If the process had been a biological one, temperature over 40-50 °C would show a retardation of the process. It may be concluded therefore, that the oxidation of black mud at the air is a chemical, non-biological process.

It has been stated repeatedly that the oxidation of sulphur at the air may take place without the influence of organisms, particularly when catalysed by ultraviolet light. However, the process is exceedingly slow under sterile conditions, as Miss Verhoop has been able to show. If a bit of soil is added to the culture media the process is enormously speeded up and the Thiobacillus, therefore, actually catalyses the exothermic reaction:

We shall not hesitate to name this reaction an example of a geobiological process. From the thesis cited, it also appeared that, under anaerobic and sterile conditions pyrite (FeS₂) originated from troilite FeS and S, as both mineralogical and X-ray control showed. The process FeS + S → FeS₂ is, therefore, non-biological. Of a great many processes, however, the cause remains obscure, of others the cause is contested. Modern mineralogy, for example (Escher, 1939) claims biological origin for (sedimentary) sulphur deposits, while Correns (1939) claims all gypsum deposits (which could easily originate from sulphur by oxidation in the presence of Ca and Mg) are of marine origin and are derived from evaporated seawater.

In the section on calcareous sediments, we shall meet with a similar controversy. Natural waters may become easily supersaturated with calcium carbonate. The work of the Laboratory of the Senckenbergianum, however, has shown, how careful one has to be to exclude biological influence in calcite deposition from supersaturated solutions! A peculiar problem is given by the so called self combustion of hay, a problem closely related to that of temperature increase during fermentation of tobacco leaf and high temperature measured in the spathe of certain Araceous flowers (van Herk, 1937) or Nymphaeaceae. Relegated, in the older literature (Molisch; Miehe, 1907) to necrobiotic or biotic changes in the plant,⁸⁴ Miehe (1930) showed that sterile plant material (intact!), showed hardly any temperature increase.⁸⁵ Gaümann was able to show that diseased plant tissue reacted by light (+0.1 °C) temperature increase (potato fever!).⁸⁶ Miehe (1930) ascribed the rise in temperature of peas etc. in Dewar flasks as observed by Molisch to the action of bacteria. His theory of the temperature increase in hay stacks is microbiological (see p. 216 of his book). Recently mown wet grass, however, may increase in temperature up to 65 °C in a few hours. It seems plausible, therefore, that Schwarz and Laupper (1922, p. 351-365), also in view of extra physiological temperatures (100-300 °C) observed in hay stacks promote a chemical theory. Quite recently Noack (1943) called attention to the role that the so called pyrophoric iron in the leaf plastid may play in this process as a catalyser.⁸⁷ It may still be that we should find a multiplicity of causes for temperature elevation. Vital and necrobiotic processes microbiological as well as chemical processes each playing a role.

In sediment geology organisms play an important role, if the sediment as in the case of clay is a more or less flocculated suspension, or whether the organism functioned as nuclei of crystallisation in an oversaturated solution (gypsum, calcite) the effect is similar, in as much as the action depends upon the activity of the organism. From sedimentation proper we segregate those phenomena that are dependent upon profound changes in the milieu (shifts of equilibria etc.) which have been dealt with at other places. But one form of sedimentation which has a decided biochemical side, has to be mentioned here. Allen (1934) found the influence of algae upon the travertine sedimentation in Mammoth Hot Springs, Yellowstone Park to be negligible. According to van Niel (1932), however, in cooler waters the deposition of milieu could be enhanced by the functional activity of the algae. Photosynthesis

requires water and it may well be that local decrease of water contents of the silica-charged water may so far change the concentration as to exceed markedly the solubility product of SiO₂.

Supersaturation prevented van ‘t Hoff (1912) to experiment with natural seawater upon the deposition of oceanic salt.⁸⁹ When the total concentration of salt is about 11%, Ca₂SO₄.2H₂O should precipitate. As a matter of fact, the solution becomes a rather stable colloidal suspension. Outside the tropics, the suspension is clarified by the action of the brine worm, the phyllopod crustacea Artemiasalina (Kuenen and Baas Becking, 1938; Warren, Kuenen and Baas Becking, 1938). This small crustacean is a so called ‘Strudler’ (Lang) it whirls the water towards its mouth and mechanically makes the external milieu pass through its intestinal tract, but the fact remains that a few of these shrimps are able to clear a quart of brine within 2 hours. The gypsum lying in pellets on the bottom of the jar. The effect may also be obtained by means of stable BaSO₄ suspensions which shows up better. Practical briners call Artemia ‘the clearer worm.’ An old Italian foreman once told he thought that he couldn’t make good salt without Artemia. As at that time the older work of Audouin was unknown to him the thing seemed very much like a fairy story.

In the tropics, where Artemia does not occur, the gypsum is taken out of the brine by means of sulphate reducing bacteria, which, with the aid of iron, form the insoluble FeS, which impregnates the loamy bottom of the pans as a tough black mud (see Section 9).

The activity of Cardium edule, the heart shell (Senckenbergiana, 14, 1932, Schwarz, p. 118. Der tierische Einflusz auf die Meeressedimente),⁹⁰ several times already mentioned great activity. Mytilus and Cardiumedulis stabilise the suspended clay in “coproliths”, which are rather resistant and form sediments. According to Schwarz this sediment containing much organic matter may be an “inbitumen.” None of the low clay region (Wadden) N. of the Dutch and German coast is nothing but recent and sub-fossil coproliths. The animals have to make use of silt.

Richter, Natur und Museum 5, p. 50, (1927), reports on Sandkorallen Riffe in den Nordsee. Here a worm Sabellariaalveolate L. makes organic coral-like reefs, metres high, in the sand. In Devonian we find fossil quartz like it. It makes evil, the worm whirls the sand grains towards its mouth and sticks then together with particles. In this way it builds land. Discovered 1920 the worm was long known, but it makes on a still bottom very irregular tubes, beautiful pictures! Mytilis edulis may kill the whole community, (Galaine and Houlbert, Les Récifs d’Hermelles et l’assèchement de la Baie de Mont Saint Michel, Bull. Soc. Geol. et Min. de Bretagne, 2, p. 319, 1921) shows that Sabellaria reefs form as dam of 3 km wide of small islands 10 km long. A lagoon has been separated. The reefs are 6 m high. Therefore, Sabellaria may form regular rock, which only with dynamite or metal nets, may be removed.⁹¹

Linné is quoted as having said “omno calx ex vivo.” This statement expresses modern opinions in a restricted sense. As Wattenberg has shown, natural waters, and in particular seawaters, are, at the surface, oversaturated in calcium carbonate (see also Sections 3.6.2 and 3.13.4). This oversaturation changes with the temperature (diagram in side cover of this book),⁹² at the equator the oversaturation may reach 300%. The solution may remain stable, but CaCO₂ may crystallise out around active nuclei. The full treatment of the topic would require a large space (this section has to be elaborated considerably later!). We follow the classification of Correns (1939, pp. 193-194) which shall be given with a few additions.

a) Plant

𝛼) Benthonic algae: (Chara, Corallinines, Halomids etc.).

𝛽) Planktonic algae: (Coccolithes).

b) Animals

𝛼) Benthonic: Corals, Sponges, Foraminafera, Bryozoa, Brachiopoda, Echinodermata, Molluscs, Worms.

𝛽) Plankton: Foraminafera, Pleropods.

𝛾) Nektonic: Crustacaea.

a) Green plants, CO₂ assimilation

b) Bacteria, NH₃ Production

Each of these items would require a separate section. Globigerina cover 128 × 10⁶ km², this is 37.1% of the ocean bottom or 25% of the earth’s surface. Average CaCO₃ 65%.

Pondweed, Potamogeton lucens may contribute 5 g CaCO₃/cm².

Dolomites are also partly biogenic. The chemical CaCO₃ deposition at the Bermudas consists of fine needles of aragonite. Calcite is found in coralline. Baas Becking and Irving, 1925 [= 1924] have shown that here the assimilation and the intracellular CaCO₃ deposition may be segregated by filtering the excess base (A of Wattenberg [[B] in the formula below]) in the light and in the dark (Coralline and Amphizoa) (see Fig. 6.7).

The population equation has been simplified by Wattenberg for seawater as [H⁺] approximately equals [OH^-] and may therefore be written: ⁹³

Mechanical CaCO₃ deposits occur in soils with ascending water circulation (African desert) and also in caves etc. where stalagmite formation occurs. Section 6.6.5 should be extended by those mechanical and chemical deposits. Still the overwhelming part belong to the biogenic sediment.

The school of Rudolf Richter has done much to drive home the idea that the role of the organism in the sediment formation is even larger as we even had expected.⁹⁴ And in the cases treated we only have demonstrated the impact of the problem. The influence of the organism upon the composition of soil, hydrosphere, atmosphere and sediment is enormous. There exists an almost classic treatise, written by a young fellow countryman, who unfortunately died when still quite young. Van Dieren (1934), in his Organogene Dünenbildung, has claimed that the formation of the sand dunes, both as geomorphological and as geochemical phenomenon, is profoundly influenced by organisms. Beginning with the moving sand in the beach and ending with the podsolised heather, van Dieren (1934) traces the influence of the higher plants on this beautiful sequence of events and convinces us, that even in this unexpected corner the influence of life upon dead material prevails.⁹⁵