- Email: [email protected]
Humans, humus, and universe
Applied Soil Ecology xxx (xxxx) xxx–xxx
Contents lists available at ScienceDirect
Applied Soil Ecology journal homepage: www.elsevier.com/locate/apsoil
Short communication
Humans, humus, and universe Augusto Zanella1,
⁎
University of Padova, Department TESAF, Viale dell’Università 16, 35020 Legnaro (Agripolis), Italy
A R T I C L E I N F O
A B S T R A C T
Keywords: Humus Internal energy Entropy Natural evolution Life Olympic Games Global Change Second law of thermodynamics Soil Organic Carbon Soil biodiversity Anthopocene
By inverting the movement of the galaxies, which are constantly moving (except the ones forming local clusters) away from each other and thanks to a system of complex equations, astrophysicists have found that all matter detected in a 13.799 billion light-year radius was originally contained in a volume 1024 times smaller than an atom. In the same spirit, a relationship between the processes of biodegradation and the general evolution of the entire universe is suggested in this short communication. This reflexion aims at answering questions related to humus systems from a biological perspective: Why is life always the result of recycling of previously formed structures? Why do organisms get old and die? The cyclic succession of life and death can be puzzling and may go beyond a scientific discussion into a more existential realm relating matter, life essences, and even philosophical or religious considerations. To read in moderation.
1. Light and internal energy Not visible to the naked eye, billions of bacterial cells are living in each cubic meter of air we breathe, millions are growing on each squared cm of our skin, billions inside our body (microbiome) and billions develop in each gram of productive soil. What about invisible light photons? It is well known that light has a double-sided existence: an “inertial essence” of matter particles behaving like minuscule bullets and an “electromagnetic essence” acting like waves. Both are running through the space at 299 792 458 m/s. Nothing can go faster than light. To go as fast as light, matter has to become light. It has to transform into something we still do not yet understand. Matter bathes in a sea of light, always and everywhere. This flux of electromagnetic waves puts matter particles in communication and keeps them in equilibrium at a shared “energetic level” The concept of internal energy may help in understanding what matter is and how a dynamic exchange of energy might be related to an exciting concept of life. Internal energy can be explained considering three of its components: a) kinetic energy, due to the microscopic motion of the composing particles (translations, rotations, vibrations of molecules or atoms); b) potential energy, related to the forces between the particles (attraction, repulsion, chemical bonds); c) mass energy: in case of thermonuclear reactions – we have to use Einstein’s formula (E = mc2) – accounting for consistent gains or losses of mass. More
⁎
1
simply, a change in internal energy is registered following changes in temperature (kinetic energy), and/or heat (potential energy), and/or mass (matter). In this article, admitting a certain inaccuracy, the word “light” is used as synonym of “electromagnetic waves” and the word “temperature” as an estimation of the “internal energy level” of a given mass of matter. If the first approximation is only a question of the domain of the same variable, the second might be wrong if taken without precautions. Interdepending kinetic, potential, and mass energies may change in opposing directions. In an attempt to avoid confusion, in the following text we will us “temperature” as a synonym of “internal energy” for purely conceptual and practical purposes. We consider that temperature and internal energy are positively correlated, meaning that they operate in the same manner and are intrinsically intertwined and inseparable. Light can transfer energy from more energetic to less excited particles, until reaching a temperature of equilibrium (Fig. 1). The transfer of energy caused by light is literally “magic”: a part of a particle matter becomes light through lose of its inertial mass and thus is transformed into a wave form. When this light particle reaches another particle under the form of electromagnetic waves it becomes inertial mass again, the receiving particle becoming heavier. Usually matter cannot stop irradiating its internal energy. As if it were obliged to lose light in order to feed colder matter around it, as a star in dark cold space. In doing so, the light passes through the matter
Tel.:+39 0498272755; fax: +39 0498272686. E-mail address: [email protected]. Music while reading? Naragonia – Lilac/Dave The Watchman: https://www.youtube.com/watch?v=PKiprmZJ43M.
http://dx.doi.org/10.1016/j.apsoil.2017.07.009 Received 19 March 2017; Received in revised form 6 July 2017; Accepted 7 July 2017 0929-1393/ © 2017 Elsevier B.V. All rights reserved.
Please cite this article as: Zanella, A., Applied Soil Ecology (2017), http://dx.doi.org/10.1016/j.apsoil.2017.07.009
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
Darwin (1859) compares the human eye and telescope evolutions, the former led by the Creator and the second by man. We will see that a younger Schrödinger, who knew of the existence of the DNA, proposed a different explanation observing the evolution of similar human inventions. Four steps resume the Darwinian theory: 1) Through a procesuss of reproduction, a genetic character (today we say “genetic”, Darwin was not aware of this notion) can express itself in a larger number of individuals, each one with singular and slightly different morphological and functional characteristics; 2) these functional differences (example: a more performing insectivore beak on a bird) are selected by the environment, because they are more adapted for exploiting a given habitat (a beak catching insects hidden in small holes, for instance) in a precise historical moment (because these insects are numerous); 3) at each reproductive cycle the environmental conditions may change and will obviously act as feedback on the selection process operating on performing individuals; 4) a long-time period of reproduction/selection involving a great number of individuals generates the observed renovation of the species.
Fig. 1. Matter particles exchanging energy/matter thanks to electromagnetic waves. 1) The particle on the left is more excited (at higher temperature) than the same particle on the right at lower temperature. For this reason, the particle on the left of the scale is heavier than the same particle in the right; 2) particles in electromagnetic equilibrium, the one on the left yielding part of its internal energy to the one on the right thanks to an electromagnetic exchange.
like water in a mill wheel, which turns and conserves as long as possible its inertial newly received energy (Fig. 2). This phenomenon is similar to the one that links life and death. Dying, organisms disappear and become source of nutriments for new organisms. Living organisms are continuously enriched by material coming from decomposing organisms, microorganisms and DNA fragments (Ascher et al., 2012; Cartenì et al., 2016; Lal et al., 2015; Nagler et al., 2016).
2.2. Erwin Schrödinger (1887–1961) Considering evolution as a means of transport, Schrödinger (1967) gave an “as if Lamarck were right” interpretation of the evolution. JeanBaptiste Lamarck (1744–1829) believed that an organism changes during its life in order to adapt to environmental changes and that this same organism can pass on this changes to its offspring. As a matter of fact, recent experiments reopened this question,: Chen et al. (2016), Heard and Martienssen (2014), Rechavi et al. (2011). Schrödinger stated that “the true parallel of the evolutionary development of organisms could be illustrated, for example, by a historical exhibition of bicycles, showing how this machine gradually changed from year to year, from decade to decade, or, in the same way, of railway-engines, motor-cars, acroplanes, typewriters, etc. […] We must, of course, not think that ‘behaviour’ after all gradually intrudes into the chromosome structure (or what not) and acquires ‘loci’ there. It is the new organs
2. What’s natural evolution? Why can we not stop growing older? There are physical joining biological reasons. None is exhaustive. The journey among them may be amusing. 2.1. Charles Darwin (1809–1882) In a section of The Origin of Species by Means of natural Selection,
Fig. 2. Representation of the relationship between the second law of thermodynamics and the processes of matter structuration and decomposition: a) General evolution of a confined system of gas molecules (or other “clusters of matter”). The represented moving matter tends to occupy a larger volume and respecting the second law of thermodynamics, the less probable system on the left evolves towards the more probable system illustrated on the right; b) an expanding universe works like a system evolving from left to right of the figure, because the place in which the matter may diffuse is increasing and temperature lowing. This allows the formation of “local clusters” respecting the second law of the thermodynamics, which imposes a general increase of the entropy in the long run. Notice that even light may “evolve”, from a relatively low number of high-energy photons in a “small universe” to a larger number of low-energy photons in a larger universe.
2
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
themselves (and they do become genetically fixed) that carry along with them the habit and the way of using them. Selection would be powerless in ‘producing’ a new organ if selection was not aided all along by the organism’s making appropriate use of it. And this is very essential. For thus, the two things go quite parallel and are ultimately, or indeed at every stage, fixed genetically as one thing: a used organ − as if Lamarck were right.”
functional units [unit of nature, in the sense of Tansley (1935)], belong to other systems at different scales inside an infinite universe that is constantly changing and expanding (as in Nottale, 2010). Ecosystems renew themselves thanks to a soil interface [among many papers: Baddeley et al. (2017), Garau et al. (2017), KögelKnabner (2017), Pizzeghello et al. (2017), Trivedi et al. (2017)]. In this process, the soil plays the role of a digestive system. Each ecosystem has a specific coevolving soil (Cartenì et al., 2016). Because of the second law of the thermodynamics, which states that the entropy of the entire universe, considered as an isolated system, will never diminish (Boltzmann (1909), review in Reeves (1986) and Feynman (2006)), every ecosystem has to develop a soil allowing compensation between decreasing and increasing entropy. In fact, building ordered structures (decreasing locally the entropy) may be possible on the condition that sooner or later these structures must return to their original dispersed bricks increasing the entropy, as requested by the second law of the thermodynamic (Fig. 2). A tree can use its photosynthetic chemical means and fix light and atoms in molecules in its leaves, on the condition that sooner or later an inverse process of decomposition shall compensate the previously diminished entropy. This process of decomposition takes place in the soil and reduces large molecules into smaller ones, freeing the previously chained energy. Similarly, sky galaxies and stars systems may form on the condition that an average number of structural units become free sooner or later elsewhere. This phenomenon was written by Ludwig Boltzmann in a formula (engraved on his tombstone at the Vienna Zentralfriedhof): S = kB ln W, where: S = entropy kB = Boltzmann’s constant ln = natural logarithm W = “Wahrscheinlichkeit”, a German word meaning the probability of occurrence of the number of possible microstates (positions and momenta of elementary particles) corresponding to the macroscopic state of a system. This formula states that the number of possible microstates (proportional to the number of elementary particles that constitutes a closed system) is exponentially related (logarithm relationship) to the quantity of entropy. Applied to natural ecosystems (a forest, or even smaller systems like single living organisms, cells…), this law predicts that structured and well organised living systems are possible only if they are able to create entropy elsewhere, which is possible in an expanding universe (Fig. 2). A natural system produces a lot of photons, which irradiate into space. The number of infrared photons leaving our planet into space is very large. They come from incident and energetic sun light photons, which are transformed by the system in numerous infrared photons. This process occurs all over the planet in every natural ecosystem, which can be seen as “engines” for transforming visible energetic sun light (λ = 400-700 nanometres) into infrared light (λ > 700 nm) made of less energetic photons. Note that this visible light is not even the strongest form of energy arriving on Earth from the Sun. As stated above, the more particles released, the more important the growth of entropy and the more stable the whole universe with all its organised systems and released particles. Following this logic, the system Earth with its produced infrared photons is more probable than the same system with a smaller number of visible photons. Because of photosynthesis, plants capture part of the sun’s energy and store this light energy in organic structures. At the soil and humus levels, a chain of living organisms degrades fallen litter, extracting energy previously stored in them by living plants. The longer the chain, the higher the number of steps that energy must cross before delivery (Fig. 3). As at each step, energy is lost in the form of infrared photons, the higher the number of steps and the higher the number of released infrared photons [interestingly, even cell roots have photoreceptors and can perceive light conducted through the plant tissues (Lee et al., 2016)]. Humus and soil extend the chain of chemical reactions allowing
2.3. Jean Perrin (1870–1942) Perrin (1923): “I have observed the possibility to warm water in dropping a mass (Joule effect). The contrary, raising a weight and cooling water, seems not absurd but in fact is never possible. We can accept as ‘second principle’ the following proposal: “when a change is spontaneously realisable, the contrary is never possible”. Or, under a more intuitive formulation: “an isolated system never passes through a preceding stage”. Thus, the second principle appears as a principle of evolution. I cannot resume here the discussion that justifies this point of view, which gives in a simple manner the several notions related to the second principle (usable energy and entropy)”. 2.4. Jacques Monod (1910–1976) Monod (1970): “The information enrichment corresponding to the formation of a three-dimensional structure comes from the fact that the genetic information (represented by the sequence) expresses itself into well-defined initial conditions (in aqueous phase, between narrow limits of temperature, ionic composition, etc.) so that only one among the possible structures is really accomplished. The initial conditions, as a consequence, contribute uniquely to eliminate other possible structures, offering then, or rather imposing one univocal interpretation of a message a priori partially equivocal”. 2.5. Richard Feynman (1918–1988) Feynman (2006), remembering a lecture given in 1963: “From some reason, the universe at one time had a very low entropy for its energy content, and since then the entropy has increased. So that is the way toward the future. That is the origin of all irreversibility, that is what makes the processes of growth and decay, that makes us remember the past and not the future, remember the things which are closer to that moment in the history of the universe when the order was higher than now, and why we are not able to remember things where the disorder is higher than now, which we call the future”. 2.6. A possible synthesis: the Ludwig Boltzmann (1844–1906) legacy The impossibility to raise a weight making water cooler is compared to the irreversibility of the process of evolution. Made of matter, all systems (even living organisms, because themselves are composed of smaller “systems”), should change in a direction that makes entropy increase. Initial conditions influence, in an unpredictable manner, the process of forming a new system [historical research and theories in Lorenz (1963), Mandelbrot (1983), May and Oster (1976); review in Gleick (1988) and Ruelle (1991); critical reading in Shenker (1994); new theoretical developments in Nottale (2010, 2003, 1998, 1993), Nottale and Schumacher (1998), Nottale et al. (2002), Chaline (2003); an attempt to explore the genesis of humus systems in Zanella et al. (2001)]. Individuals in a confined ecosystem, and/or molecules in a limited aqueous system, are both submitted to selection processes. The selected individuals or molecules have to respond to the changing functionality of a renewing system (humus molecules, for instance: Nannipieri et al., 1996; Ponge, 2013; Stevenson, 1983). Finally, subject to evolution are not just molecules [as genes in Dawkins (1976, 2006)], nor individuals, even collected in “populations” and defining “species” as in Darwin (1859), but these plus their environments, considered as 3
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
Fig. 3. Life under spotlight. A curtain of light may hide the mystery of life: the more the photons, the thicker the curtain, and the higher the entropy and complexity of Earth ecosystems. Crusts systems on rocky substrate or equivalent less complex ecosystems (to the left) are less able to reduce the incident radiation than complex forest ecosystems on structured soil (to the right: larger plant community, larger number of animals and microorganisms in a more structured physical-chemical habitat). Made of a low number of high energy visible photons of high frequency, the incident radiation is transformed in a leaving radiation made of a high number of low energy and low frequency infrared photons. The higher the complexity, the higher the number of steps that energy must accomplish for returning to the space. Each step generating new low frequency photons, the higher the number of steps, the higher the number of released infrared photons. Like in the picture, life on planet Earth looks like a rolling ball set on a slope, ineluctably falling along an inclined plane of increasing biodiversity. The process may be related to the universe expansion, as shown in Fig. 2.
matter and energy in our universe (from https://science.nasa.gov/ astrophysics/focus-areas/what-is-dark-energy: “fitting a theoretical model of the composition of the universe to the combined set of cosmological observations, scientists have come up with the composition that we described above, ∼68% dark energy, ∼27% dark matter, ∼5% normal matter.”)? Reality 1: This short animation (33 s) shows the location of one among the farthest galaxies ever seen. The video [made by NASA, ESA, and G. Bacon (STScI); science – NASA, ESA, P. Oesch (Yale University), G. Brammer (STScI), P. van Dokkum (Yale University), and G. Illingworth (University of California, Santa Cruz)] begins by locating the Big Dipper in the Ursa Major constellation, then zooms out of our Milky Way into a mist made of galaxies, ending with the image of the young galaxy GN-z11 (https://www.nasa.gov/feature/goddard/2016/ hubble-team-breaks-cosmic-distance-record). This primordial galaxy existed 13.4 billion years in the past, just 400 million years after the big bang, when the universe was only three percent of its present age. Reality 2: Andrew Z. Colvin arranged this space-time conception as a Russian matryoshka doll, starting with planet Earth and zooming out 7 times until arriving at the entire observable universe: http:// twistedsifter.com/2012/10/putting-the-size-of-the-observableuniverse-in-perspective/. The expanding universe resembles the one sketched in Fig. 2, groups and clusters of galaxies merging to form larger ones, until composing the whole observable universe. A living soil is made up of organic-mineral aggregates. We define these aggregates as being biomicro, biomeso, or biomacro structures. They can be detected by the naked eye and are classified by size: (< 1), (1–4) and (> 4) mm respectively (for details and figures: Humusica 1, article 4). These aggregates are continuously recycled in an active soil. On the contrary, a poorly active soil (low biodiversity) is made principally of massive or single-grained features. In fact, we say that it lacks structure, mainly with large coarse clay blocks (> 5–10 cm), or sandy loamy texture free of small mineral grains. The universe shows a non-homogeneous structure, made of star systems aggregated into galaxies, these
previously built organic structures to be decomposed into their smallest components, which at the current planet temperature, are infrared photons and small molecules or atoms. Growth and decomposition are thus possible because they are interdependent. It is relatively easy to detect even in ordinary landscapes or “units of nature” (Tansley, 1935) similar to the ones sketched in Fig. 3. In temperate climates, they can evolve in a way similar to imaginary spherical volumes racing down a slope of limiting ecological constraints and, as a result, increasing their biodiversity, moving from pioneer ecosystems (for instance Crusto and Bryo humus systems, in Humusica 2 article 13) to common mature and complex forest ecosystems. On another level of reflexion, ecosystems on Earth can be considered to be functionally similar to the cold (3 K) intergalactic space, where galaxies and invisible dark matter and energy are still challenging human imagination. In the third part of the article, we will enlarge our quest to stars, galaxies, and intergalactic space while still looking for a general explanation of evolutionary processes.
3. Comparing the evolution process at different scales Hubble (1936) discovered that galaxies are running away at high speed from our Local Group of galaxies (the one containing our Milky Way). By inverting their movement and using mathematical tools, astrophysicists developed the theory of a highly concentrated initial “grain”, which exploded 13.8 billion years ago generating the famous “Big Bang.” Because of its extreme consistence, this still unexplained germinal point exploded, generating usual and dark matter, energy and light. Even the time and space system that we know, in which the expansion of the universe operates and continues, was generated at that point in time. Is it possible to consider that a living universe made of locally dying structures is generating new universe parts elsewhere? Is it scientifically acceptable that matter falling into black holes comes out elsewhere as universe embryons? What are the indiscernible proportions of dark matter and energy that constitutes the largest part of 4
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
Fig. 4. The universe shows a non-homogeneous structure, made of star systems aggregated into galaxies, these forming clusters and then superclusters. Because of the continuing cycle of generation, augmentation, and disintegration of clusters, the entire universe is constantly evolving like an immense living organism.
Fig. 5. Dipole Repeller and Shapley Attractor (from Hoffmann et al., 2017) compared to a very small cluster of humic molecules (from Piccolo, 2002). Aside and occupying the rest of the picture, a dancing natural evolution of planet Earth (medals representing the beginning of planet Earth on the left and its evolution towards more biodiverse consistence, many collected in internet), bathing in a dark substrate (dark matter and energy, electromagnetic and gravity waves), which resembles to a mass of humus. In the centre of the picture, the “Pioneer plaque” placed by NASA in 1972 and 1973 on Pioneer 10 and 11 space crafts, featuring a pictorial message for possible extraterrestrial intelligent creatures.
black holes. The apparent absence of such a population is still under investigation. Reality 4: In far space, a force is imposing a global movement to the Local Galactic Group of galaxies in which our Milky Way evolves (Tully et al., 2014). In fact, the Local Galactic Group is situated half way between a huge Supercluster of galaxies called Shapley and a very large empty space named Dipole Repeller. Because of this disposition of matter, the Local Group (in a larger Supercluster) is attracted by Shapley Supercluster and pushed by the Dipole Repeller. Hoffman et al.
forming clusters and then superclusters. Because of the continuing cycle of generation, augmentation, and disintegration of clusters, the entire universe is constantly evolving like an immense living soil (Fig. 4). Reality 3: Trakhtenbrot et al. (2016) analysed 14 faint, X-ray-selected active galactic nuclei, corresponding to black holes, in a volume of Cosmos field. Compared to preceding studies, they succeeded in improving by one order of magnitude the precision to detect high redshifts. In the deepest X-ray available source, they hoped to estimate the accretion rate of a significant population of hidden supermassive 5
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
DNA modifications that express controlled functionalities within a given organism in a targeted ecosystem. Even worse: it is possible to induce a non-controlled chain of reactions that may interfere with current processes and cause unforecasted and dangerous evolutions (Maghari and Ardekani, 2011). As other molecules, DNA’s are governed by the systems in which they exist and evolve. Humans are able to influence the natural evolution at their scale (ITPS, 2015). Generally, it is relatively easy to impose a regression to a natural system, which comes back to preceding stages of evolution, biologically and energetically poorer, made of less complex structures and with a net diminished number of relationships between their components (Huhta, 2007; Kelley, 1990). It is more difficult to increase biodiversity. We probably do it against our will, in generating what we call “globalisation”, i.e. a new planet Earth made of a more mixed and strongly interconnected new biosphere. As humans, we need to know how to use the soil for producing sufficient food and water for us and for the ecosystem in which we all are evolving. One possible way is producing food using composts, or functionally controlled hydroponic systems. We certainly must recover the natural inherited soil, because it could be the best and the most “compatible with what we are today,” and try to co-evolve in harmony with it and with its bacteria and other living organisms.
(2017) calculated that the Local Group is approaching the Shapley attractor with a speed of 631 ± 20 km/s (top-left,). Reality 5: What is soil? Soil is not a “thing”. Many soil definitions are reported in Humusica 1, article 1. All of them are less effective than the abstract of an article published by Hole (1981) and titled “Effect of animals on soil”: “Soil is defined here in terms of arbitrary boundaries rather than of functions of a soil body. Soil animals are defined in relation to their effects on the soil body. Animals living in the soil body and intimately related to it are indeed part of the soil. Animals living above the soil make contributions to it. Many animals are amphihabitant, that is, they live for a time in the soil and then in environments outside the soil. Exopedonic (outside the soil) and endopedonic (inside the soil) animals are considered with respect to twelve activities: mounding, mixing, forming voids, back-filling voids, forming and destroying peds, regulating soil erosion, regulating movement of water and air in soil, regulating plant litter, regulating nutrient cycling, regulating biota, and producing special constituents. Animals participate in numerous processes of soil formation and affect the usefulness of soils”. Reality 6: There is evidence for recent exchange of antibiotic resistance genes between soil bacteria and clinical pathogens (Forsberg et al., 2012). We come from the soil and we cannot live without it (Gilbert and Neufeld, 2014; McFall-Ngai et al., 2013). Reality 7: In the soil, the processes of aggregation and decomposition produce micro-structures (bottom-left, Fig. 5). Following “humeomic studies” (Canellas et al., 2010; Piccolo, 2002) humic acids are made of smaller molecules – hydrosoluble constituents, non-covalently, weakly ester-bound or strongly ester-bound organic soluble components and other unextractable residues – which can be aromatic (planar ring-shaped molecules, with delocalized π electrons), aliphatic (atoms in linear chains) and hydrophobic or hydrophilic compounds. All these molecules interact in the soil and form suprastructures (super-microcluster). For instance, we know that hydrophobic compounds with linear chains or regular stackable aromatic rings are more abundant in larger suprastructures, while hydrophilic irregularly shaped components are instead eluted in the smallest sized suprastructures (Nebbioso and Piccolo, 2012). Independent of scale, clusters of galaxies and humus molecules are actually both aggregates of matter. In both cases, this matter bathes in a flux of gravitational and electromagnetic waves, which fill the space everywhere and put large and small scales in communication at light speed (red lines in Fig. 5). In this perspective, living on the planet Earth means, essentially a) responding to gravitational waves and turning around a star; b) absorbing electromagnetic waves (light, photons) and returning them to the space, keeping inside for as long as possible the largest part of them (the largest number of photons). Our sun (6000 K) delivers photons into the dark space (3 K). A very low part of them arrives on our planet and is provisionally captured in inorganic and organic molecules. Thanks to a process of accumulation of photons in larger molecules, plants break water molecules, extracting their electrons. The internal energy of these electrons is then transferred in energetic molecules, involving atoms of Carbon previously taken in the air and forming new organic matter. Consuming organic matter, heterotroph organisms can partially recuperate this energetic value. During all processes of biotransformation, photons flee away, returning to the space. Working like a sucking machine, an expanding universe is extracting photons from matter, entertaining a never-ending process of life.
5. Conclusion If life and death cannot be avoided because much is still unknown about matter properties, the need for survival of the Homo sapiens species should make us acknowledge that we need organised processes of feedback. For instance, it is probably safer to adopt a less incisive agriculture and adopt cultural practices that preserve soil biodiversity [following Fukuoka (1985) principles, or organic farming processes…]. Also, better understand the natural laws that generated, maintained, and prepared the soil of our ecosystems, in equilibrium with a universe in perpetual co-evolution, could be a mandatory prerogative. As living organisms, we are engulfed in a general design, which is larger than our knowledge. Charles Darwin (a very good bird hunter when young (Darwin, 1887), might be wrong on a crucial point: we cannot win the fight for life. Because in the end single individuals inevitably die. Combined hazardous single actions can produce unhappy coordinated effects (as a climate warming, for instance). Reeves (1986), developed and supported by data in (Reeves, 2013; Reeves and Lenoir, 2009), expressed a very judicious opinion, that may summarize the content of this article: “The universe generates complexity. Complexity generates efficacy. But efficacy does not necessarily generate sense. It can even generate non-sense. An arbitrary act is necessary to get sense and avoid non-sense. Humans must begin to make decisions as a conscious Homo sapiens species, collectively, in order to assure the survival of the planet Earth niche and habitat. […] If we have a role to play in the universe, it might be just the one to accompany nature to deliver by herself.” Global change looks like a first real universal challenge. Before things get worse, humanity should be involved in a referendum: a) A crucial question, during a world manifestation such as the Olympic Games could be (why not in Pyeongchang in 2018 and in Tokyo in 2020?) an effective way to use media at a world scale: “As planet Earth citizens, will you stop the climate from warming?” b) Citizens phone-messages (with identity card reference of all persons older than 5) may be collected at the level of Olympic Organisation and the “yes” or “no” answers counted; c) the Olympic Games Organisers may announce the score on a world scale, as a humanity will. Scientists may also be asked to prepare other crucial questions for coming Olympic Games.
4. Anthropocene and soil biodiversity When James Watson and Francis Crick presented the structure of the DNA-helix in 1953, and given the ability we have to detect all the sequences of bases, we, as a human society, thought ourselves capable of modifying genes and building Supermen (and other useful GMOs). But with DNA units being elements of larger systems, and their sequences related to functional organisms, it is still not easy to obtain
It is possible that photons – the ones we do not see at all (even less 6
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
Arabidopsis thaliana roots., Sci. Sci. Signal. 9, ra106. http://dx.doi.org/10.1126/ scisignal.aaf6530. Lorenz, E.N., 1963. Deterministic nonperiodic flow. J. Atmos. Sci. 20, 130–141. http:// dx.doi.org/10.1175/1520-0469(1963)020<0130:DNF>2.0.CO;2. Maghari, B.M., Ardekani, A.M., 2011. Genetically modified foods and social concerns. Avicenna J. Med. Biotechnol. Mandelbrot, B.B., 1983. The Fractal Geometry of Nature/Revised and Enlarged Edition/. New York. May, R.M., Oster, G.F., 1976. Bifurcations and dynamic complexity in simple ecological models. Am. Nat. 110, 573–599. http://dx.doi.org/10.1086/283092. McFall-Ngai, M., Hadfield, M.G., Bosch, T.C.G., Carey, H.V., Domazet-Lošo, T., Douglas, A.E., Dubilier, N., Eberl, G., Fukami, T., Gilbert, S.F., Hentschel, U., King, N., Kjelleberg, S., Knoll, A.H., Kremer, N., Mazmanian, S.K., Metcalf, J.L., Nealson, K., Pierce, N.E., Rawls, J.F., Reid, A., Ruby, E.G., Rumpho, M., Sanders, J.G., Tautz, D., Wernegreen, J.J., 2013. Animals in a bacterial world, a new imperative for the life sciences. Proc. Natl. Acad. Sci. 110, 3229–3236. http://dx.doi.org/10.1073/pnas. 1218525110. Monod, J., 1970. Le hazard et la nécessité Essai sur la philosophie naturelle de la biologie moderne. Points Sci., Paris. Nagler, M., Ascher, J., Gómez-Brandón, M., Insam, H., 2016. Soil microbial communities along the route of a venturous cycling trip. Appl. Soil Ecol. http://dx.doi.org/10. 1016/j.apsoil.2015.11.010. Nannipieri, P., Sequi, P., Fusi, P., 1996. Humus and enzyme activity. Humic Subst. Terr. Ecosyst. 293–328. http://dx.doi.org/10.1016/B978-044481516-3/50008-6. Nebbioso, A., Piccolo, A., 2012. Advances in humeomics: enhanced structural identification of humic molecules after size fractionation of a soil humic acid. Anal. Chim. Acta 720, 77–90. http://dx.doi.org/10.1016/j.aca.2012.01.027. Nottale, L., Schumacher, G., 1998. Scale relativity, fractal space–time and gravitational structures. Fractals Beyond Complexities Sci. World Sci London, UK 0, 149–160. Nottale, L., Chaline, J., Grou, P., 2002. On the fractal structure of evolutionary trees. In: Losa, G.A., Merlini, D., Nonnenmacher, T.F., Weibel, E.R. (Eds.), Fractals in Biology and Medicine. Birkh{ä}user, Basel, pp. 247–258. http://dx.doi.org/10.1007/978-30348-8119-7_25. Nottale, L., 1993. Fractal Space-time and Microphysics: Towards a Theory of Scale Relativity. World Scientific. Nottale, L., 1998. La Relativité Dans Tous Ses états: Au Delà De l’Espace-Temps. Hachette, Hachette Paris, France. Nottale, L., 2003. Scale-relativistic cosmology. Chaos Solitons Fractals 16, 539–564. http://dx.doi.org/10.1016/S0960-0779(02)00222-9. Nottale, L., 2010. Scale relativity and fractal space-time: theory and applications. Found. Sci. 15, 101–152. http://dx.doi.org/10.1007/s10699-010-9170-2. Perrin, J., 1923. Notice Sur Les Travax Scientifiques De Jean Perrin. Imprimerie, Toulouse, France. Piccolo, A., 2002. The supramolecular structure of humic substances: a novel understanding of humus chemistry and implications in soil science. Adv. Agron. 75, 57–134. http://dx.doi.org/10.1016/S0065-2113(02)75003-7. Pizzeghello, D., Francioso, O., Concheri, G., Muscolo, A., Nardi, S., 2017. Land use affects the soil C sequestration in alpine environment, NE Italy. Forests 8. http://dx.doi.org/ 10.3390/f8060197. Ponge, J.F., 2013. Plant-soil feedbacks mediated by humus forms: a review. Soil Biol. Biochem. http://dx.doi.org/10.1016/j.soilbio.2012.07.019. Rechavi, O., Minevich, G., Hobert, O., 2011. Transgenerational inheritance of an acquired small RNA-based antiviral response in C. elegans. Cell. http://dx.doi.org/10.1016/j. cell.2011.10.042. Reeves, H., Lenoir, F., 2009. Terracide. Cormorant Books Inc. Reeves, H., 1986. L’heure De Senivrer. Lunivers a-t-il Un Sens? In: Du Seu, Ed. (Ed.), Paris. Reeves, H., 2013. Là où Croît Le Peril…croît Aussi Ce Qui Sauve. Edition du., Paris, France. Schrödinger, E., 1967. What Is Life? Mind and Matter, Genetic Fixation of Habits and Skills. Shenker, O.R., 1994. Fractal geometry is not the geometry of nature. Stud. Hist. Philos. Sci. 25, 967–981. http://dx.doi.org/10.1016/0039-3681(94)90072-8. Stevenson, F.J., 1983. Humus chemistry: genesis, composition. Reactions. Nature 303, 835–836. http://dx.doi.org/10.1016/0146-6380(83)90043-8. Tansley, A.G., 1935. The use and abuse of vegetational terms and concepts. Ecology 16, 284–307. http://dx.doi.org/10.2307/1930070. Trakhtenbrot, B., Civano, F., Urry, C.M., Schawinski, K., Marchesi, S., Elvis, M., Rosario, D.J., Suh, H., Mejia-Restrepo, J.E., Simmons, B.D., Faisst, A.L., Onodera, M., 2016. Faint COSMOS AGNs at z∼3.3. I. black hole properties and constraints on early black hole growth. Astrophys. J. 825, 4. Trivedi, P., Delgado-Baquerizo, M., Trivedi, C., Hamonts, K., Anderson, I.C., Singh, B.K., 2017. Keystone microbial taxa regulate the invasion of a fungal pathogen in agroecosystems. Soil Biol. Biochem. http://dx.doi.org/10.1016/j.soilbio.2017.03.013. Tully, R.B., Courtois, H., Hoffman, Y., Pomarède, D., 2014. The Laniakea supercluster of galaxies. Nature 513, 71–73. http://dx.doi.org/10.1038/nature13674. Zanella, A., Tomasi, M., Cesare, D.S., Frizzera, L., Jabiol, B., Nicolini, G., Sartori, G., Calabrese, M.S., Manacabelli, A., Nardi, S., Pizzeghello, D., Maurizio, O., 2001. Humus Forestali − Manuale Di Ecologia Per Il Riconoscimento E l’interpretazione − Applicazione Alle Faggete. Centro di. ed. Edmund Mach Fondazione (San Michele all’Adige) Trento, Trento (Italy).
than we see bacteria in the air we breathe), the ones who are neither particles nor waves, are forcing us to grow older. It is possible that an expanding universe, draining photons in an increasing volume of spacetime, might be the cause of the observed natural evolution. Are we living because photons come (as visible light, from the sun), give something to us (free energetic electrons), and leave (as infrared photons) our planet in order to fill an expanding universe? If this is an acceptable hypothesis, it is time to better investigate the processes of organic matter recycling and organisms’ death. They may correspond to living, evolution feedbacks carried on at soil level by invisible microorganisms. References Ascher, J., Sartori, G., Graefe, U., Thornton, B., Ceccherini, M.T., Pietramellara, G., Egli, M., 2012. Are humus forms, mesofauna and microflora in subalpine forest soils sensitive to thermal conditions? Biol. Fertil. Soils 48, 709–725. http://dx.doi.org/10. 1007/s00374-012-0670-9. Baddeley, J.A., Edwards, A.C., Watson, C.A., 2017. Changes in soil C and N stocks and C:N stoichiometry 21 years after land use change on an arable mineral topsoil. Geoderma 303, 19–26. http://dx.doi.org/10.1016/j.geoderma.2017.05.002. Boltzmann, L., 1909. Wissenschaftliche Abhandlungen. In: Hasenöh, F. (Ed.), . Canellas, L.P., Piccolo, A., Dobbss, L.B., Spaccini, R., Olivares, F.L., Zandonadi, D.B., Façanha, A.R., 2010. Chemical composition and bioactivity properties of size-fractions separated from a vermicompost humic acid. Chemosphere 78, 457–466. http:// dx.doi.org/10.1016/j.chemosphere.2009.10.018. Cartenì, F., Bonanomi, G., Giannino, F., Incerti, G., Vincenot, C.E., Chiusano, M.L., Mazzoleni, S., 2016. Self-DNA inhibitory effects: underlying mechanisms and ecological implications. Plant Signal. Behav. 11, e1158381. http://dx.doi.org/10.1080/ 15592324.2016.1158381. Chaline, J., 2003. Continu versus discontinu, lin??aire versus non lin??aire dans l’??volution des esp??ces. Comptes Rendus – Palevol 2, 413–421. http://dx.doi.org/10. 1016/j.crpv.2003.09.025. Chen, Q., Yan, W., Duan, E., 2016. Epigenetic inheritance of acquired traits through sperm RNAs and sperm RNA modifications. Nat. Rev. Genet. 17, 733–743. http://dx. doi.org/10.1038/nrg.2016.106. Darwin, C., 1859. L’origine Delle Specie Per Selezione Naturale. Grandi tas, Roma. Darwin, F., 1887. The Life and Letters of Charles Darwi, Including an Autobiographical Chapter. In: Murra, John (Ed.), London. Dawkins, R., 1976. The Selfish Gene. Oxford Uni, Oxford. Dawkins, R., 2006. The Selfish Gene: 30th Anniversary Edition–with a New Introduction by the Author. Oxford University Press citeulike-article-id:636057. Feynman, R., 2006. Lectures on Physics, Definitive. Library of Congress Cataloging in Publishing Data. Forsberg, K.J., Reyes, A., Wang, B., Selleck, E.M., Sommer, M.O.A., Dantas, G., 2012. The shared antibiotic resistome of soil bacteria and human pathogens. Science(80-) 337, 1107–1111. http://dx.doi.org/10.1126/science.1220761. Fukuoka, M., 1985. The Naturam Way of Farming. The Theory and Practice of Green Philosophy. Reprint 20, Madras, India. Garau, G., Silvetti, M., Vasileiadis, S., Donner, E., Diquattro, S., Deiana, S., Lombi, E., Castaldi, P., 2017. Use of municipal solid wastes for chemical and microbiological recovery of soils contaminated with metal(loid)s. Soil Biol. Biochem. 111, 25–35. http://dx.doi.org/10.1016/j.soilbio.2017.03.014. Gilbert, J.A., Neufeld, J.D., 2014. Life in a world without microbes. PLoS Biol. 12. http:// dx.doi.org/10.1371/journal.pbio.1002020. Gleick, J., 1988. Chaos, making a new science. Am. J. Phys. http://dx.doi.org/10.1119/1. 15345. Heard, E., Martienssen, R.A., 2014. Transgenerational epigenetic inheritance: myths and mechanisms. Cell. http://dx.doi.org/10.1016/j.cell.2014.02.045. Hoffman, Y., Pomarède, D., Tully, R.B., Courtois, H.M., 2017. The dipole repeller. Nat. Astron. 1, 36. Hole, F.D., 1981. Effects of animals on soil. Geoderma 25, 75–112. Hubble, E., 1936. Effects of red shifts on the distribution of nebulae. Astrophys. Journal. 84, 517–554. http://dx.doi.org/10.1086/143782. Huhta, V., 2007. The role of soil fauna in ecosystems: a historical review. Pedobiologia (Jena) 50, 489–495. http://dx.doi.org/10.1016/j.pedobi.2006.08.006. ITPS, F. and 2015 Status of the World’s Soil Resources (SWSR) – Technical Summary. Rome, Italy Kögel-Knabner, I., 2017. The macromolecular organic composition of plant and microbial residues as inputs to soil organic matter: fourteen years on. Soil Biol. Biochem. http://dx.doi.org/10.1016/j.soilbio.2016.08.011. Kelley, H.W., 1990. Keeping the Land Alive. Soil Erosion: Its Causes and Cures. M-57, Roma. Lal, R., Negassa, W., Lorenz, K., 2015. Carbon sequestration in soil. Curr. Opin. Environ. Sustain. http://dx.doi.org/10.1016/j.cosust.2015.09.002. Lee, H.-J., Ha, J.-H., Kim, S.-G., Choi, H.-K., Kim, Z.H., Han, Y.-J., Kim, J.-I., Oh, Y., Fragoso, V., Shin, K., Hyeon, T., Choi, H.-G., Oh, K.-H., Baldwin, I.T., Park, C.-M., 2016. Stem-piped light activates phytochrome B to trigger light responses in
7
Contents lists available at ScienceDirect
Applied Soil Ecology journal homepage: www.elsevier.com/locate/apsoil
Short communication
Humans, humus, and universe Augusto Zanella1,
⁎
University of Padova, Department TESAF, Viale dell’Università 16, 35020 Legnaro (Agripolis), Italy
A R T I C L E I N F O
A B S T R A C T
Keywords: Humus Internal energy Entropy Natural evolution Life Olympic Games Global Change Second law of thermodynamics Soil Organic Carbon Soil biodiversity Anthopocene
By inverting the movement of the galaxies, which are constantly moving (except the ones forming local clusters) away from each other and thanks to a system of complex equations, astrophysicists have found that all matter detected in a 13.799 billion light-year radius was originally contained in a volume 1024 times smaller than an atom. In the same spirit, a relationship between the processes of biodegradation and the general evolution of the entire universe is suggested in this short communication. This reflexion aims at answering questions related to humus systems from a biological perspective: Why is life always the result of recycling of previously formed structures? Why do organisms get old and die? The cyclic succession of life and death can be puzzling and may go beyond a scientific discussion into a more existential realm relating matter, life essences, and even philosophical or religious considerations. To read in moderation.
1. Light and internal energy Not visible to the naked eye, billions of bacterial cells are living in each cubic meter of air we breathe, millions are growing on each squared cm of our skin, billions inside our body (microbiome) and billions develop in each gram of productive soil. What about invisible light photons? It is well known that light has a double-sided existence: an “inertial essence” of matter particles behaving like minuscule bullets and an “electromagnetic essence” acting like waves. Both are running through the space at 299 792 458 m/s. Nothing can go faster than light. To go as fast as light, matter has to become light. It has to transform into something we still do not yet understand. Matter bathes in a sea of light, always and everywhere. This flux of electromagnetic waves puts matter particles in communication and keeps them in equilibrium at a shared “energetic level” The concept of internal energy may help in understanding what matter is and how a dynamic exchange of energy might be related to an exciting concept of life. Internal energy can be explained considering three of its components: a) kinetic energy, due to the microscopic motion of the composing particles (translations, rotations, vibrations of molecules or atoms); b) potential energy, related to the forces between the particles (attraction, repulsion, chemical bonds); c) mass energy: in case of thermonuclear reactions – we have to use Einstein’s formula (E = mc2) – accounting for consistent gains or losses of mass. More
⁎
1
simply, a change in internal energy is registered following changes in temperature (kinetic energy), and/or heat (potential energy), and/or mass (matter). In this article, admitting a certain inaccuracy, the word “light” is used as synonym of “electromagnetic waves” and the word “temperature” as an estimation of the “internal energy level” of a given mass of matter. If the first approximation is only a question of the domain of the same variable, the second might be wrong if taken without precautions. Interdepending kinetic, potential, and mass energies may change in opposing directions. In an attempt to avoid confusion, in the following text we will us “temperature” as a synonym of “internal energy” for purely conceptual and practical purposes. We consider that temperature and internal energy are positively correlated, meaning that they operate in the same manner and are intrinsically intertwined and inseparable. Light can transfer energy from more energetic to less excited particles, until reaching a temperature of equilibrium (Fig. 1). The transfer of energy caused by light is literally “magic”: a part of a particle matter becomes light through lose of its inertial mass and thus is transformed into a wave form. When this light particle reaches another particle under the form of electromagnetic waves it becomes inertial mass again, the receiving particle becoming heavier. Usually matter cannot stop irradiating its internal energy. As if it were obliged to lose light in order to feed colder matter around it, as a star in dark cold space. In doing so, the light passes through the matter
Tel.:+39 0498272755; fax: +39 0498272686. E-mail address: [email protected]. Music while reading? Naragonia – Lilac/Dave The Watchman: https://www.youtube.com/watch?v=PKiprmZJ43M.
http://dx.doi.org/10.1016/j.apsoil.2017.07.009 Received 19 March 2017; Received in revised form 6 July 2017; Accepted 7 July 2017 0929-1393/ © 2017 Elsevier B.V. All rights reserved.
Please cite this article as: Zanella, A., Applied Soil Ecology (2017), http://dx.doi.org/10.1016/j.apsoil.2017.07.009
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
Darwin (1859) compares the human eye and telescope evolutions, the former led by the Creator and the second by man. We will see that a younger Schrödinger, who knew of the existence of the DNA, proposed a different explanation observing the evolution of similar human inventions. Four steps resume the Darwinian theory: 1) Through a procesuss of reproduction, a genetic character (today we say “genetic”, Darwin was not aware of this notion) can express itself in a larger number of individuals, each one with singular and slightly different morphological and functional characteristics; 2) these functional differences (example: a more performing insectivore beak on a bird) are selected by the environment, because they are more adapted for exploiting a given habitat (a beak catching insects hidden in small holes, for instance) in a precise historical moment (because these insects are numerous); 3) at each reproductive cycle the environmental conditions may change and will obviously act as feedback on the selection process operating on performing individuals; 4) a long-time period of reproduction/selection involving a great number of individuals generates the observed renovation of the species.
Fig. 1. Matter particles exchanging energy/matter thanks to electromagnetic waves. 1) The particle on the left is more excited (at higher temperature) than the same particle on the right at lower temperature. For this reason, the particle on the left of the scale is heavier than the same particle in the right; 2) particles in electromagnetic equilibrium, the one on the left yielding part of its internal energy to the one on the right thanks to an electromagnetic exchange.
like water in a mill wheel, which turns and conserves as long as possible its inertial newly received energy (Fig. 2). This phenomenon is similar to the one that links life and death. Dying, organisms disappear and become source of nutriments for new organisms. Living organisms are continuously enriched by material coming from decomposing organisms, microorganisms and DNA fragments (Ascher et al., 2012; Cartenì et al., 2016; Lal et al., 2015; Nagler et al., 2016).
2.2. Erwin Schrödinger (1887–1961) Considering evolution as a means of transport, Schrödinger (1967) gave an “as if Lamarck were right” interpretation of the evolution. JeanBaptiste Lamarck (1744–1829) believed that an organism changes during its life in order to adapt to environmental changes and that this same organism can pass on this changes to its offspring. As a matter of fact, recent experiments reopened this question,: Chen et al. (2016), Heard and Martienssen (2014), Rechavi et al. (2011). Schrödinger stated that “the true parallel of the evolutionary development of organisms could be illustrated, for example, by a historical exhibition of bicycles, showing how this machine gradually changed from year to year, from decade to decade, or, in the same way, of railway-engines, motor-cars, acroplanes, typewriters, etc. […] We must, of course, not think that ‘behaviour’ after all gradually intrudes into the chromosome structure (or what not) and acquires ‘loci’ there. It is the new organs
2. What’s natural evolution? Why can we not stop growing older? There are physical joining biological reasons. None is exhaustive. The journey among them may be amusing. 2.1. Charles Darwin (1809–1882) In a section of The Origin of Species by Means of natural Selection,
Fig. 2. Representation of the relationship between the second law of thermodynamics and the processes of matter structuration and decomposition: a) General evolution of a confined system of gas molecules (or other “clusters of matter”). The represented moving matter tends to occupy a larger volume and respecting the second law of thermodynamics, the less probable system on the left evolves towards the more probable system illustrated on the right; b) an expanding universe works like a system evolving from left to right of the figure, because the place in which the matter may diffuse is increasing and temperature lowing. This allows the formation of “local clusters” respecting the second law of the thermodynamics, which imposes a general increase of the entropy in the long run. Notice that even light may “evolve”, from a relatively low number of high-energy photons in a “small universe” to a larger number of low-energy photons in a larger universe.
2
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
themselves (and they do become genetically fixed) that carry along with them the habit and the way of using them. Selection would be powerless in ‘producing’ a new organ if selection was not aided all along by the organism’s making appropriate use of it. And this is very essential. For thus, the two things go quite parallel and are ultimately, or indeed at every stage, fixed genetically as one thing: a used organ − as if Lamarck were right.”
functional units [unit of nature, in the sense of Tansley (1935)], belong to other systems at different scales inside an infinite universe that is constantly changing and expanding (as in Nottale, 2010). Ecosystems renew themselves thanks to a soil interface [among many papers: Baddeley et al. (2017), Garau et al. (2017), KögelKnabner (2017), Pizzeghello et al. (2017), Trivedi et al. (2017)]. In this process, the soil plays the role of a digestive system. Each ecosystem has a specific coevolving soil (Cartenì et al., 2016). Because of the second law of the thermodynamics, which states that the entropy of the entire universe, considered as an isolated system, will never diminish (Boltzmann (1909), review in Reeves (1986) and Feynman (2006)), every ecosystem has to develop a soil allowing compensation between decreasing and increasing entropy. In fact, building ordered structures (decreasing locally the entropy) may be possible on the condition that sooner or later these structures must return to their original dispersed bricks increasing the entropy, as requested by the second law of the thermodynamic (Fig. 2). A tree can use its photosynthetic chemical means and fix light and atoms in molecules in its leaves, on the condition that sooner or later an inverse process of decomposition shall compensate the previously diminished entropy. This process of decomposition takes place in the soil and reduces large molecules into smaller ones, freeing the previously chained energy. Similarly, sky galaxies and stars systems may form on the condition that an average number of structural units become free sooner or later elsewhere. This phenomenon was written by Ludwig Boltzmann in a formula (engraved on his tombstone at the Vienna Zentralfriedhof): S = kB ln W, where: S = entropy kB = Boltzmann’s constant ln = natural logarithm W = “Wahrscheinlichkeit”, a German word meaning the probability of occurrence of the number of possible microstates (positions and momenta of elementary particles) corresponding to the macroscopic state of a system. This formula states that the number of possible microstates (proportional to the number of elementary particles that constitutes a closed system) is exponentially related (logarithm relationship) to the quantity of entropy. Applied to natural ecosystems (a forest, or even smaller systems like single living organisms, cells…), this law predicts that structured and well organised living systems are possible only if they are able to create entropy elsewhere, which is possible in an expanding universe (Fig. 2). A natural system produces a lot of photons, which irradiate into space. The number of infrared photons leaving our planet into space is very large. They come from incident and energetic sun light photons, which are transformed by the system in numerous infrared photons. This process occurs all over the planet in every natural ecosystem, which can be seen as “engines” for transforming visible energetic sun light (λ = 400-700 nanometres) into infrared light (λ > 700 nm) made of less energetic photons. Note that this visible light is not even the strongest form of energy arriving on Earth from the Sun. As stated above, the more particles released, the more important the growth of entropy and the more stable the whole universe with all its organised systems and released particles. Following this logic, the system Earth with its produced infrared photons is more probable than the same system with a smaller number of visible photons. Because of photosynthesis, plants capture part of the sun’s energy and store this light energy in organic structures. At the soil and humus levels, a chain of living organisms degrades fallen litter, extracting energy previously stored in them by living plants. The longer the chain, the higher the number of steps that energy must cross before delivery (Fig. 3). As at each step, energy is lost in the form of infrared photons, the higher the number of steps and the higher the number of released infrared photons [interestingly, even cell roots have photoreceptors and can perceive light conducted through the plant tissues (Lee et al., 2016)]. Humus and soil extend the chain of chemical reactions allowing
2.3. Jean Perrin (1870–1942) Perrin (1923): “I have observed the possibility to warm water in dropping a mass (Joule effect). The contrary, raising a weight and cooling water, seems not absurd but in fact is never possible. We can accept as ‘second principle’ the following proposal: “when a change is spontaneously realisable, the contrary is never possible”. Or, under a more intuitive formulation: “an isolated system never passes through a preceding stage”. Thus, the second principle appears as a principle of evolution. I cannot resume here the discussion that justifies this point of view, which gives in a simple manner the several notions related to the second principle (usable energy and entropy)”. 2.4. Jacques Monod (1910–1976) Monod (1970): “The information enrichment corresponding to the formation of a three-dimensional structure comes from the fact that the genetic information (represented by the sequence) expresses itself into well-defined initial conditions (in aqueous phase, between narrow limits of temperature, ionic composition, etc.) so that only one among the possible structures is really accomplished. The initial conditions, as a consequence, contribute uniquely to eliminate other possible structures, offering then, or rather imposing one univocal interpretation of a message a priori partially equivocal”. 2.5. Richard Feynman (1918–1988) Feynman (2006), remembering a lecture given in 1963: “From some reason, the universe at one time had a very low entropy for its energy content, and since then the entropy has increased. So that is the way toward the future. That is the origin of all irreversibility, that is what makes the processes of growth and decay, that makes us remember the past and not the future, remember the things which are closer to that moment in the history of the universe when the order was higher than now, and why we are not able to remember things where the disorder is higher than now, which we call the future”. 2.6. A possible synthesis: the Ludwig Boltzmann (1844–1906) legacy The impossibility to raise a weight making water cooler is compared to the irreversibility of the process of evolution. Made of matter, all systems (even living organisms, because themselves are composed of smaller “systems”), should change in a direction that makes entropy increase. Initial conditions influence, in an unpredictable manner, the process of forming a new system [historical research and theories in Lorenz (1963), Mandelbrot (1983), May and Oster (1976); review in Gleick (1988) and Ruelle (1991); critical reading in Shenker (1994); new theoretical developments in Nottale (2010, 2003, 1998, 1993), Nottale and Schumacher (1998), Nottale et al. (2002), Chaline (2003); an attempt to explore the genesis of humus systems in Zanella et al. (2001)]. Individuals in a confined ecosystem, and/or molecules in a limited aqueous system, are both submitted to selection processes. The selected individuals or molecules have to respond to the changing functionality of a renewing system (humus molecules, for instance: Nannipieri et al., 1996; Ponge, 2013; Stevenson, 1983). Finally, subject to evolution are not just molecules [as genes in Dawkins (1976, 2006)], nor individuals, even collected in “populations” and defining “species” as in Darwin (1859), but these plus their environments, considered as 3
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
Fig. 3. Life under spotlight. A curtain of light may hide the mystery of life: the more the photons, the thicker the curtain, and the higher the entropy and complexity of Earth ecosystems. Crusts systems on rocky substrate or equivalent less complex ecosystems (to the left) are less able to reduce the incident radiation than complex forest ecosystems on structured soil (to the right: larger plant community, larger number of animals and microorganisms in a more structured physical-chemical habitat). Made of a low number of high energy visible photons of high frequency, the incident radiation is transformed in a leaving radiation made of a high number of low energy and low frequency infrared photons. The higher the complexity, the higher the number of steps that energy must accomplish for returning to the space. Each step generating new low frequency photons, the higher the number of steps, the higher the number of released infrared photons. Like in the picture, life on planet Earth looks like a rolling ball set on a slope, ineluctably falling along an inclined plane of increasing biodiversity. The process may be related to the universe expansion, as shown in Fig. 2.
matter and energy in our universe (from https://science.nasa.gov/ astrophysics/focus-areas/what-is-dark-energy: “fitting a theoretical model of the composition of the universe to the combined set of cosmological observations, scientists have come up with the composition that we described above, ∼68% dark energy, ∼27% dark matter, ∼5% normal matter.”)? Reality 1: This short animation (33 s) shows the location of one among the farthest galaxies ever seen. The video [made by NASA, ESA, and G. Bacon (STScI); science – NASA, ESA, P. Oesch (Yale University), G. Brammer (STScI), P. van Dokkum (Yale University), and G. Illingworth (University of California, Santa Cruz)] begins by locating the Big Dipper in the Ursa Major constellation, then zooms out of our Milky Way into a mist made of galaxies, ending with the image of the young galaxy GN-z11 (https://www.nasa.gov/feature/goddard/2016/ hubble-team-breaks-cosmic-distance-record). This primordial galaxy existed 13.4 billion years in the past, just 400 million years after the big bang, when the universe was only three percent of its present age. Reality 2: Andrew Z. Colvin arranged this space-time conception as a Russian matryoshka doll, starting with planet Earth and zooming out 7 times until arriving at the entire observable universe: http:// twistedsifter.com/2012/10/putting-the-size-of-the-observableuniverse-in-perspective/. The expanding universe resembles the one sketched in Fig. 2, groups and clusters of galaxies merging to form larger ones, until composing the whole observable universe. A living soil is made up of organic-mineral aggregates. We define these aggregates as being biomicro, biomeso, or biomacro structures. They can be detected by the naked eye and are classified by size: (< 1), (1–4) and (> 4) mm respectively (for details and figures: Humusica 1, article 4). These aggregates are continuously recycled in an active soil. On the contrary, a poorly active soil (low biodiversity) is made principally of massive or single-grained features. In fact, we say that it lacks structure, mainly with large coarse clay blocks (> 5–10 cm), or sandy loamy texture free of small mineral grains. The universe shows a non-homogeneous structure, made of star systems aggregated into galaxies, these
previously built organic structures to be decomposed into their smallest components, which at the current planet temperature, are infrared photons and small molecules or atoms. Growth and decomposition are thus possible because they are interdependent. It is relatively easy to detect even in ordinary landscapes or “units of nature” (Tansley, 1935) similar to the ones sketched in Fig. 3. In temperate climates, they can evolve in a way similar to imaginary spherical volumes racing down a slope of limiting ecological constraints and, as a result, increasing their biodiversity, moving from pioneer ecosystems (for instance Crusto and Bryo humus systems, in Humusica 2 article 13) to common mature and complex forest ecosystems. On another level of reflexion, ecosystems on Earth can be considered to be functionally similar to the cold (3 K) intergalactic space, where galaxies and invisible dark matter and energy are still challenging human imagination. In the third part of the article, we will enlarge our quest to stars, galaxies, and intergalactic space while still looking for a general explanation of evolutionary processes.
3. Comparing the evolution process at different scales Hubble (1936) discovered that galaxies are running away at high speed from our Local Group of galaxies (the one containing our Milky Way). By inverting their movement and using mathematical tools, astrophysicists developed the theory of a highly concentrated initial “grain”, which exploded 13.8 billion years ago generating the famous “Big Bang.” Because of its extreme consistence, this still unexplained germinal point exploded, generating usual and dark matter, energy and light. Even the time and space system that we know, in which the expansion of the universe operates and continues, was generated at that point in time. Is it possible to consider that a living universe made of locally dying structures is generating new universe parts elsewhere? Is it scientifically acceptable that matter falling into black holes comes out elsewhere as universe embryons? What are the indiscernible proportions of dark matter and energy that constitutes the largest part of 4
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
Fig. 4. The universe shows a non-homogeneous structure, made of star systems aggregated into galaxies, these forming clusters and then superclusters. Because of the continuing cycle of generation, augmentation, and disintegration of clusters, the entire universe is constantly evolving like an immense living organism.
Fig. 5. Dipole Repeller and Shapley Attractor (from Hoffmann et al., 2017) compared to a very small cluster of humic molecules (from Piccolo, 2002). Aside and occupying the rest of the picture, a dancing natural evolution of planet Earth (medals representing the beginning of planet Earth on the left and its evolution towards more biodiverse consistence, many collected in internet), bathing in a dark substrate (dark matter and energy, electromagnetic and gravity waves), which resembles to a mass of humus. In the centre of the picture, the “Pioneer plaque” placed by NASA in 1972 and 1973 on Pioneer 10 and 11 space crafts, featuring a pictorial message for possible extraterrestrial intelligent creatures.
black holes. The apparent absence of such a population is still under investigation. Reality 4: In far space, a force is imposing a global movement to the Local Galactic Group of galaxies in which our Milky Way evolves (Tully et al., 2014). In fact, the Local Galactic Group is situated half way between a huge Supercluster of galaxies called Shapley and a very large empty space named Dipole Repeller. Because of this disposition of matter, the Local Group (in a larger Supercluster) is attracted by Shapley Supercluster and pushed by the Dipole Repeller. Hoffman et al.
forming clusters and then superclusters. Because of the continuing cycle of generation, augmentation, and disintegration of clusters, the entire universe is constantly evolving like an immense living soil (Fig. 4). Reality 3: Trakhtenbrot et al. (2016) analysed 14 faint, X-ray-selected active galactic nuclei, corresponding to black holes, in a volume of Cosmos field. Compared to preceding studies, they succeeded in improving by one order of magnitude the precision to detect high redshifts. In the deepest X-ray available source, they hoped to estimate the accretion rate of a significant population of hidden supermassive 5
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
DNA modifications that express controlled functionalities within a given organism in a targeted ecosystem. Even worse: it is possible to induce a non-controlled chain of reactions that may interfere with current processes and cause unforecasted and dangerous evolutions (Maghari and Ardekani, 2011). As other molecules, DNA’s are governed by the systems in which they exist and evolve. Humans are able to influence the natural evolution at their scale (ITPS, 2015). Generally, it is relatively easy to impose a regression to a natural system, which comes back to preceding stages of evolution, biologically and energetically poorer, made of less complex structures and with a net diminished number of relationships between their components (Huhta, 2007; Kelley, 1990). It is more difficult to increase biodiversity. We probably do it against our will, in generating what we call “globalisation”, i.e. a new planet Earth made of a more mixed and strongly interconnected new biosphere. As humans, we need to know how to use the soil for producing sufficient food and water for us and for the ecosystem in which we all are evolving. One possible way is producing food using composts, or functionally controlled hydroponic systems. We certainly must recover the natural inherited soil, because it could be the best and the most “compatible with what we are today,” and try to co-evolve in harmony with it and with its bacteria and other living organisms.
(2017) calculated that the Local Group is approaching the Shapley attractor with a speed of 631 ± 20 km/s (top-left,). Reality 5: What is soil? Soil is not a “thing”. Many soil definitions are reported in Humusica 1, article 1. All of them are less effective than the abstract of an article published by Hole (1981) and titled “Effect of animals on soil”: “Soil is defined here in terms of arbitrary boundaries rather than of functions of a soil body. Soil animals are defined in relation to their effects on the soil body. Animals living in the soil body and intimately related to it are indeed part of the soil. Animals living above the soil make contributions to it. Many animals are amphihabitant, that is, they live for a time in the soil and then in environments outside the soil. Exopedonic (outside the soil) and endopedonic (inside the soil) animals are considered with respect to twelve activities: mounding, mixing, forming voids, back-filling voids, forming and destroying peds, regulating soil erosion, regulating movement of water and air in soil, regulating plant litter, regulating nutrient cycling, regulating biota, and producing special constituents. Animals participate in numerous processes of soil formation and affect the usefulness of soils”. Reality 6: There is evidence for recent exchange of antibiotic resistance genes between soil bacteria and clinical pathogens (Forsberg et al., 2012). We come from the soil and we cannot live without it (Gilbert and Neufeld, 2014; McFall-Ngai et al., 2013). Reality 7: In the soil, the processes of aggregation and decomposition produce micro-structures (bottom-left, Fig. 5). Following “humeomic studies” (Canellas et al., 2010; Piccolo, 2002) humic acids are made of smaller molecules – hydrosoluble constituents, non-covalently, weakly ester-bound or strongly ester-bound organic soluble components and other unextractable residues – which can be aromatic (planar ring-shaped molecules, with delocalized π electrons), aliphatic (atoms in linear chains) and hydrophobic or hydrophilic compounds. All these molecules interact in the soil and form suprastructures (super-microcluster). For instance, we know that hydrophobic compounds with linear chains or regular stackable aromatic rings are more abundant in larger suprastructures, while hydrophilic irregularly shaped components are instead eluted in the smallest sized suprastructures (Nebbioso and Piccolo, 2012). Independent of scale, clusters of galaxies and humus molecules are actually both aggregates of matter. In both cases, this matter bathes in a flux of gravitational and electromagnetic waves, which fill the space everywhere and put large and small scales in communication at light speed (red lines in Fig. 5). In this perspective, living on the planet Earth means, essentially a) responding to gravitational waves and turning around a star; b) absorbing electromagnetic waves (light, photons) and returning them to the space, keeping inside for as long as possible the largest part of them (the largest number of photons). Our sun (6000 K) delivers photons into the dark space (3 K). A very low part of them arrives on our planet and is provisionally captured in inorganic and organic molecules. Thanks to a process of accumulation of photons in larger molecules, plants break water molecules, extracting their electrons. The internal energy of these electrons is then transferred in energetic molecules, involving atoms of Carbon previously taken in the air and forming new organic matter. Consuming organic matter, heterotroph organisms can partially recuperate this energetic value. During all processes of biotransformation, photons flee away, returning to the space. Working like a sucking machine, an expanding universe is extracting photons from matter, entertaining a never-ending process of life.
5. Conclusion If life and death cannot be avoided because much is still unknown about matter properties, the need for survival of the Homo sapiens species should make us acknowledge that we need organised processes of feedback. For instance, it is probably safer to adopt a less incisive agriculture and adopt cultural practices that preserve soil biodiversity [following Fukuoka (1985) principles, or organic farming processes…]. Also, better understand the natural laws that generated, maintained, and prepared the soil of our ecosystems, in equilibrium with a universe in perpetual co-evolution, could be a mandatory prerogative. As living organisms, we are engulfed in a general design, which is larger than our knowledge. Charles Darwin (a very good bird hunter when young (Darwin, 1887), might be wrong on a crucial point: we cannot win the fight for life. Because in the end single individuals inevitably die. Combined hazardous single actions can produce unhappy coordinated effects (as a climate warming, for instance). Reeves (1986), developed and supported by data in (Reeves, 2013; Reeves and Lenoir, 2009), expressed a very judicious opinion, that may summarize the content of this article: “The universe generates complexity. Complexity generates efficacy. But efficacy does not necessarily generate sense. It can even generate non-sense. An arbitrary act is necessary to get sense and avoid non-sense. Humans must begin to make decisions as a conscious Homo sapiens species, collectively, in order to assure the survival of the planet Earth niche and habitat. […] If we have a role to play in the universe, it might be just the one to accompany nature to deliver by herself.” Global change looks like a first real universal challenge. Before things get worse, humanity should be involved in a referendum: a) A crucial question, during a world manifestation such as the Olympic Games could be (why not in Pyeongchang in 2018 and in Tokyo in 2020?) an effective way to use media at a world scale: “As planet Earth citizens, will you stop the climate from warming?” b) Citizens phone-messages (with identity card reference of all persons older than 5) may be collected at the level of Olympic Organisation and the “yes” or “no” answers counted; c) the Olympic Games Organisers may announce the score on a world scale, as a humanity will. Scientists may also be asked to prepare other crucial questions for coming Olympic Games.
4. Anthropocene and soil biodiversity When James Watson and Francis Crick presented the structure of the DNA-helix in 1953, and given the ability we have to detect all the sequences of bases, we, as a human society, thought ourselves capable of modifying genes and building Supermen (and other useful GMOs). But with DNA units being elements of larger systems, and their sequences related to functional organisms, it is still not easy to obtain
It is possible that photons – the ones we do not see at all (even less 6
Applied Soil Ecology xxx (xxxx) xxx–xxx
A. Zanella
Arabidopsis thaliana roots., Sci. Sci. Signal. 9, ra106. http://dx.doi.org/10.1126/ scisignal.aaf6530. Lorenz, E.N., 1963. Deterministic nonperiodic flow. J. Atmos. Sci. 20, 130–141. http:// dx.doi.org/10.1175/1520-0469(1963)020<0130:DNF>2.0.CO;2. Maghari, B.M., Ardekani, A.M., 2011. Genetically modified foods and social concerns. Avicenna J. Med. Biotechnol. Mandelbrot, B.B., 1983. The Fractal Geometry of Nature/Revised and Enlarged Edition/. New York. May, R.M., Oster, G.F., 1976. Bifurcations and dynamic complexity in simple ecological models. Am. Nat. 110, 573–599. http://dx.doi.org/10.1086/283092. McFall-Ngai, M., Hadfield, M.G., Bosch, T.C.G., Carey, H.V., Domazet-Lošo, T., Douglas, A.E., Dubilier, N., Eberl, G., Fukami, T., Gilbert, S.F., Hentschel, U., King, N., Kjelleberg, S., Knoll, A.H., Kremer, N., Mazmanian, S.K., Metcalf, J.L., Nealson, K., Pierce, N.E., Rawls, J.F., Reid, A., Ruby, E.G., Rumpho, M., Sanders, J.G., Tautz, D., Wernegreen, J.J., 2013. Animals in a bacterial world, a new imperative for the life sciences. Proc. Natl. Acad. Sci. 110, 3229–3236. http://dx.doi.org/10.1073/pnas. 1218525110. Monod, J., 1970. Le hazard et la nécessité Essai sur la philosophie naturelle de la biologie moderne. Points Sci., Paris. Nagler, M., Ascher, J., Gómez-Brandón, M., Insam, H., 2016. Soil microbial communities along the route of a venturous cycling trip. Appl. Soil Ecol. http://dx.doi.org/10. 1016/j.apsoil.2015.11.010. Nannipieri, P., Sequi, P., Fusi, P., 1996. Humus and enzyme activity. Humic Subst. Terr. Ecosyst. 293–328. http://dx.doi.org/10.1016/B978-044481516-3/50008-6. Nebbioso, A., Piccolo, A., 2012. Advances in humeomics: enhanced structural identification of humic molecules after size fractionation of a soil humic acid. Anal. Chim. Acta 720, 77–90. http://dx.doi.org/10.1016/j.aca.2012.01.027. Nottale, L., Schumacher, G., 1998. Scale relativity, fractal space–time and gravitational structures. Fractals Beyond Complexities Sci. World Sci London, UK 0, 149–160. Nottale, L., Chaline, J., Grou, P., 2002. On the fractal structure of evolutionary trees. In: Losa, G.A., Merlini, D., Nonnenmacher, T.F., Weibel, E.R. (Eds.), Fractals in Biology and Medicine. Birkh{ä}user, Basel, pp. 247–258. http://dx.doi.org/10.1007/978-30348-8119-7_25. Nottale, L., 1993. Fractal Space-time and Microphysics: Towards a Theory of Scale Relativity. World Scientific. Nottale, L., 1998. La Relativité Dans Tous Ses états: Au Delà De l’Espace-Temps. Hachette, Hachette Paris, France. Nottale, L., 2003. Scale-relativistic cosmology. Chaos Solitons Fractals 16, 539–564. http://dx.doi.org/10.1016/S0960-0779(02)00222-9. Nottale, L., 2010. Scale relativity and fractal space-time: theory and applications. Found. Sci. 15, 101–152. http://dx.doi.org/10.1007/s10699-010-9170-2. Perrin, J., 1923. Notice Sur Les Travax Scientifiques De Jean Perrin. Imprimerie, Toulouse, France. Piccolo, A., 2002. The supramolecular structure of humic substances: a novel understanding of humus chemistry and implications in soil science. Adv. Agron. 75, 57–134. http://dx.doi.org/10.1016/S0065-2113(02)75003-7. Pizzeghello, D., Francioso, O., Concheri, G., Muscolo, A., Nardi, S., 2017. Land use affects the soil C sequestration in alpine environment, NE Italy. Forests 8. http://dx.doi.org/ 10.3390/f8060197. Ponge, J.F., 2013. Plant-soil feedbacks mediated by humus forms: a review. Soil Biol. Biochem. http://dx.doi.org/10.1016/j.soilbio.2012.07.019. Rechavi, O., Minevich, G., Hobert, O., 2011. Transgenerational inheritance of an acquired small RNA-based antiviral response in C. elegans. Cell. http://dx.doi.org/10.1016/j. cell.2011.10.042. Reeves, H., Lenoir, F., 2009. Terracide. Cormorant Books Inc. Reeves, H., 1986. L’heure De Senivrer. Lunivers a-t-il Un Sens? In: Du Seu, Ed. (Ed.), Paris. Reeves, H., 2013. Là où Croît Le Peril…croît Aussi Ce Qui Sauve. Edition du., Paris, France. Schrödinger, E., 1967. What Is Life? Mind and Matter, Genetic Fixation of Habits and Skills. Shenker, O.R., 1994. Fractal geometry is not the geometry of nature. Stud. Hist. Philos. Sci. 25, 967–981. http://dx.doi.org/10.1016/0039-3681(94)90072-8. Stevenson, F.J., 1983. Humus chemistry: genesis, composition. Reactions. Nature 303, 835–836. http://dx.doi.org/10.1016/0146-6380(83)90043-8. Tansley, A.G., 1935. The use and abuse of vegetational terms and concepts. Ecology 16, 284–307. http://dx.doi.org/10.2307/1930070. Trakhtenbrot, B., Civano, F., Urry, C.M., Schawinski, K., Marchesi, S., Elvis, M., Rosario, D.J., Suh, H., Mejia-Restrepo, J.E., Simmons, B.D., Faisst, A.L., Onodera, M., 2016. Faint COSMOS AGNs at z∼3.3. I. black hole properties and constraints on early black hole growth. Astrophys. J. 825, 4. Trivedi, P., Delgado-Baquerizo, M., Trivedi, C., Hamonts, K., Anderson, I.C., Singh, B.K., 2017. Keystone microbial taxa regulate the invasion of a fungal pathogen in agroecosystems. Soil Biol. Biochem. http://dx.doi.org/10.1016/j.soilbio.2017.03.013. Tully, R.B., Courtois, H., Hoffman, Y., Pomarède, D., 2014. The Laniakea supercluster of galaxies. Nature 513, 71–73. http://dx.doi.org/10.1038/nature13674. Zanella, A., Tomasi, M., Cesare, D.S., Frizzera, L., Jabiol, B., Nicolini, G., Sartori, G., Calabrese, M.S., Manacabelli, A., Nardi, S., Pizzeghello, D., Maurizio, O., 2001. Humus Forestali − Manuale Di Ecologia Per Il Riconoscimento E l’interpretazione − Applicazione Alle Faggete. Centro di. ed. Edmund Mach Fondazione (San Michele all’Adige) Trento, Trento (Italy).
than we see bacteria in the air we breathe), the ones who are neither particles nor waves, are forcing us to grow older. It is possible that an expanding universe, draining photons in an increasing volume of spacetime, might be the cause of the observed natural evolution. Are we living because photons come (as visible light, from the sun), give something to us (free energetic electrons), and leave (as infrared photons) our planet in order to fill an expanding universe? If this is an acceptable hypothesis, it is time to better investigate the processes of organic matter recycling and organisms’ death. They may correspond to living, evolution feedbacks carried on at soil level by invisible microorganisms. References Ascher, J., Sartori, G., Graefe, U., Thornton, B., Ceccherini, M.T., Pietramellara, G., Egli, M., 2012. Are humus forms, mesofauna and microflora in subalpine forest soils sensitive to thermal conditions? Biol. Fertil. Soils 48, 709–725. http://dx.doi.org/10. 1007/s00374-012-0670-9. Baddeley, J.A., Edwards, A.C., Watson, C.A., 2017. Changes in soil C and N stocks and C:N stoichiometry 21 years after land use change on an arable mineral topsoil. Geoderma 303, 19–26. http://dx.doi.org/10.1016/j.geoderma.2017.05.002. Boltzmann, L., 1909. Wissenschaftliche Abhandlungen. In: Hasenöh, F. (Ed.), . Canellas, L.P., Piccolo, A., Dobbss, L.B., Spaccini, R., Olivares, F.L., Zandonadi, D.B., Façanha, A.R., 2010. Chemical composition and bioactivity properties of size-fractions separated from a vermicompost humic acid. Chemosphere 78, 457–466. http:// dx.doi.org/10.1016/j.chemosphere.2009.10.018. Cartenì, F., Bonanomi, G., Giannino, F., Incerti, G., Vincenot, C.E., Chiusano, M.L., Mazzoleni, S., 2016. Self-DNA inhibitory effects: underlying mechanisms and ecological implications. Plant Signal. Behav. 11, e1158381. http://dx.doi.org/10.1080/ 15592324.2016.1158381. Chaline, J., 2003. Continu versus discontinu, lin??aire versus non lin??aire dans l’??volution des esp??ces. Comptes Rendus – Palevol 2, 413–421. http://dx.doi.org/10. 1016/j.crpv.2003.09.025. Chen, Q., Yan, W., Duan, E., 2016. Epigenetic inheritance of acquired traits through sperm RNAs and sperm RNA modifications. Nat. Rev. Genet. 17, 733–743. http://dx. doi.org/10.1038/nrg.2016.106. Darwin, C., 1859. L’origine Delle Specie Per Selezione Naturale. Grandi tas, Roma. Darwin, F., 1887. The Life and Letters of Charles Darwi, Including an Autobiographical Chapter. In: Murra, John (Ed.), London. Dawkins, R., 1976. The Selfish Gene. Oxford Uni, Oxford. Dawkins, R., 2006. The Selfish Gene: 30th Anniversary Edition–with a New Introduction by the Author. Oxford University Press citeulike-article-id:636057. Feynman, R., 2006. Lectures on Physics, Definitive. Library of Congress Cataloging in Publishing Data. Forsberg, K.J., Reyes, A., Wang, B., Selleck, E.M., Sommer, M.O.A., Dantas, G., 2012. The shared antibiotic resistome of soil bacteria and human pathogens. Science(80-) 337, 1107–1111. http://dx.doi.org/10.1126/science.1220761. Fukuoka, M., 1985. The Naturam Way of Farming. The Theory and Practice of Green Philosophy. Reprint 20, Madras, India. Garau, G., Silvetti, M., Vasileiadis, S., Donner, E., Diquattro, S., Deiana, S., Lombi, E., Castaldi, P., 2017. Use of municipal solid wastes for chemical and microbiological recovery of soils contaminated with metal(loid)s. Soil Biol. Biochem. 111, 25–35. http://dx.doi.org/10.1016/j.soilbio.2017.03.014. Gilbert, J.A., Neufeld, J.D., 2014. Life in a world without microbes. PLoS Biol. 12. http:// dx.doi.org/10.1371/journal.pbio.1002020. Gleick, J., 1988. Chaos, making a new science. Am. J. Phys. http://dx.doi.org/10.1119/1. 15345. Heard, E., Martienssen, R.A., 2014. Transgenerational epigenetic inheritance: myths and mechanisms. Cell. http://dx.doi.org/10.1016/j.cell.2014.02.045. Hoffman, Y., Pomarède, D., Tully, R.B., Courtois, H.M., 2017. The dipole repeller. Nat. Astron. 1, 36. Hole, F.D., 1981. Effects of animals on soil. Geoderma 25, 75–112. Hubble, E., 1936. Effects of red shifts on the distribution of nebulae. Astrophys. Journal. 84, 517–554. http://dx.doi.org/10.1086/143782. Huhta, V., 2007. The role of soil fauna in ecosystems: a historical review. Pedobiologia (Jena) 50, 489–495. http://dx.doi.org/10.1016/j.pedobi.2006.08.006. ITPS, F. and 2015 Status of the World’s Soil Resources (SWSR) – Technical Summary. Rome, Italy Kögel-Knabner, I., 2017. The macromolecular organic composition of plant and microbial residues as inputs to soil organic matter: fourteen years on. Soil Biol. Biochem. http://dx.doi.org/10.1016/j.soilbio.2016.08.011. Kelley, H.W., 1990. Keeping the Land Alive. Soil Erosion: Its Causes and Cures. M-57, Roma. Lal, R., Negassa, W., Lorenz, K., 2015. Carbon sequestration in soil. Curr. Opin. Environ. Sustain. http://dx.doi.org/10.1016/j.cosust.2015.09.002. Lee, H.-J., Ha, J.-H., Kim, S.-G., Choi, H.-K., Kim, Z.H., Han, Y.-J., Kim, J.-I., Oh, Y., Fragoso, V., Shin, K., Hyeon, T., Choi, H.-G., Oh, K.-H., Baldwin, I.T., Park, C.-M., 2016. Stem-piped light activates phytochrome B to trigger light responses in
7