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Thermodynamics of Environment Journal ofMining and Metallurgy, 36 (1-2)B (2000) 93 - 110 Letters to Editor THERMODYNAMICS OF ENVIRONMENT v. M. Zhukovsky Chemistry Dept., Ural State University, 51 Lenin av., 620083, Ekaterinburg, Russia e-mail: [email protected] (Received 10 November 1999; accepted 10January 2000) Abstract A possibility of non-equilibrium thermodynamic application to analysis of systems like living organisms - environment were considered. The significance ofthe human com­ munity interaction and coexisting with the biosphere were discussed. V.I. Vernadsky (1863 - 1945) conception oftransformation the biosphere into noosphere was considered. Keywords: ecology, environment, thermodynamics, anthropogenic factor, biosphere, coevolution, noosphere. 1. Introduction The environmental problems actually have overgrown problems of local industrial company, town, city or region. The transboundary transfer of pollutants over countries and continents makes these problems very important for humanity taken as a whole. The term ecology (from Greek oikos = house, residence, and logos = word, teaching) was introduced into scientific usage by E. Haeckel in 1866. J.Min.Met. 36 (1-2)B 2000 93 Letters to Editor Ecology was regarded as a part of biology, which studied an interaction of living organism and environment (dwelling place) (Fig. I). Modern concept of environment regards ecology as part of it. Interaction ~ EmriroJtllleuW field ----Interaction Fig. 1. The environmental field. The environment involves both nonliving physical and chemical com­ ponents (sunlight, heat, moisture, wind, oxygen, carbon dioxide, nutrients in atmosphere, hydrosphere, soil) and living biological components (geneti­ cally identical bodies, each and all objects of vegetable life and animals). The terms ecology (environmental science) and economics have a common basis. Modern term environmental study, in particular, involves study of Nature economy. Living organism in its environment investigation uses different sci­ ence: climatology, hydrology, oceanography, physics, chemistry, geology and edaphology. Organism interaction study in the frames of ecology applies methods of ecology, ethology, taxonomy, physiology and mathe­ matical simulation. Genetically identical bodies, populations, community of species, ecosystems and biosphere can be considered as environmental object. It is generally recognized that modern ecology originates from C. Darwin. The main idea of evolution theory is an adaptation of living organ­ isms to environmental effects through the natural selection. Continual increase of human pressure to environment for going on the XXth century 94 i.Min.Met. 36 (I-2)B 2000 Letters to Editor to made extension the operating of ecology field. In our days environmen­ tal science get a footing as scientific basis for environmental management and biological diversity (biota) protection. At the beginning of 1970's social ecology appeared, which studies on interaction of human civilization with environment and the ways of their preservation (Fig. 2). Interaction Industrial Military Social Moral 013 ;Movable ---=--t>board Interaction <:1---of action Fig. 2. The environmental field ofmankind. Social ecology considers various philosophical, social, ethical, eco­ nomical, geographical and some aspects. At present the problem of human survival, environment protection and public health appeared to be one ofthe most important for mankind. That is why the actions for solution of domes­ tic and international environmental problems, formation of ecological way of thinking are especially important. As the result international and nation­ al agency "Greenpeace" deprecates environmental pollution. Unfortunately their unconscious emotionality and exclamatory gives quite a few to replace scientific competence and decreases the efficiency of environmental activi­ ties. Human race genesis is a natural consequence of living substance evo­ lution or more exactly coevolution of living and nonliving substance in bio­ sphere (relatively thin zone of air, soil, and water on the Earth, which is capable to being us life). Hence mankind is part of nature and it exist according to the laws of nature. J.Min. Met. 36 (1-2)B 2000 95 Letters to Editor 2. Thermodynamics method Thorough study of the interaction of living organisms with environ­ ment thermodynamics method is very fruitful. In terms of thermodynamics every organism, biota and biosphere as whole should be described as non­ isolated open strong non-equilibrium system, which exist only in stationary state when its internal parameters are stabilized on the level of survival. Stationary state stability can be preserved only as a result of intensive exchange between living system and its environment by energy, entropy, matter and information (Fig.3). For description of these systems the non­ equilibrium thermodynamics should be used. Environment (Biosphere) Fig. 3. The intensive exchange ofliving system with its environment. The second law of thermodynamics in R.Clausius form of equality-inequal­ ity can be presented as: 8Qe dS'2­ (1) T where sign of equality is valid for reversible process and sign of inequality is valid for irreversible processes. In accordance with the 1. Prigogine postulate [1,2] total entropy varia­ tion for open systems can be as a result of exchange with its environment e i (dS ) or a result of internal irreversible processes (dS ): 96 J.Min.Met. 36 (J-2)B 2000 Letters to Editor (2) In each real processes dSi > 0, and at equilibrium dSi = O. For isolated sys­ tem dSe =0 and dS =dSi ~ O. The entropy growth rate (entropy production) dS i a=&~O (3) is basic attribute for the behavior of natural processes in real time scale. If the growth of the entropy in a system have as unique origin its inter­ nal processes, the growth of entropy is due to the thermodynamic potential decrease: i a= dS =~(dGJ ~O (4) dt T dt TP The growth of the entropy for open systems functionally depend on motive force (Xi) and generating flows (J): VI == To == LXiii> 0 (5) where tflis the dissipative function, Xi are the gradients of temperature, con­ centration, electric potential, thermodynamic potential etc., and J, - the flows of heat, substance, charge, the rate of chemical reaction etc., respec­ tively. The dissipative function for the irreversible evolutionary system can be only positive (Fa >0). At first glance biological systems functioning itself leads to contradiction with the second law of thermodynamics, because any living organism creation leads to spontaneous local ordering and consequently to the decrease of the entropy in the system. Though in Eq. (5) with the sum productions l..iX/i included one part of the productions can be less then zero (X/i < 0). Total sum is positive (l..iX/i >0) as a result of several conjunctive processes. Therefore in the situation like shown above local self-organization of matter becomes possibility. For example, thermal diffusion processes: (diff)Ta <0, (therm.)Ta >0, but (diff)Ta + (therm.)Ta >0. J.Min.Met. 36 (i-2)B 2000 97 Letters to Editor For the open systems stationary we have the Eq. dS ds' dS i (J' =a' + a' =- =--+ --=0 (6) dt dt dt where every addend (if and d) differ from zero. In accordance with the I. Prigogine theorem for stationary system (Fig. 4) ddldt<O and positive function . dS i a' =--~ min (7) dt 0' (J'min ••••••••••••,;".:'"1'._----- t Fig. 4. Conversion system to stationary state. The result of irreversible processes in open systems is entropy transfer from system to environment. a b Fig. 5. The bifurcation. 98 I. Min.Met. 36 (i-2)B 2000 Letters to Editor Eqs (5) - (7) are faithfully exact only for open close to equilibrium sys­ tems (L.Onsager linear approximation). Deviation from equilibrium results to Xi and J, growth, system can loose stability and disintegrate or leave the linear thermodynamics region without loss of overall stability. However strongly non-equilibrium systems can be non-linear. In bifurcation point (Fig.5) the systems come to new stability state, new dissipative structure is formed and the system structure transforms from simple to complex one [3,4], 3. Living organism and environment The result of thermodynamic analysis shows that every living system is characterized with treatment (revised) function, namely can denature environment with entropy increase. Within all history of the Earth living organisms are very active in global element cycle (Fig. 6). As a result the essence of interaction between living matter with geo­ logical media, Earth landscape and atmosphere changed. Coral reefs and islands, calciferous rocks, soil, mine field of coal, oil and gas - are products of the revised (biogeochemical) function. In evolution process and envi­ ronment change the many kinds of living organisms were not adapted to changes and disappeared. According to the energy concept of evolution one genus can have advantages over the other ones to survive in natural selection processes if same have a mechanism on maximum reception energy and efficiency usage ones. The same principle is correct for information reception, con­ version and use. The man (Homo sapiens) is a product of evolution. After segregation from the animal world mankind created tools and obtained new powerful sources of energy (mineral fuel, natural water energy, nuclear energy). As a result the revised function of mankind increased in many thousand times. To-day mankind is the main actions factor in environment. Contrary to other living organisms, which adapted (coevaluated) to environment, mankind itself
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