Economy e Energy No 71e - Página Principal

Economical zoning needs to be widely discussed and a consensus should be reached regarding the different methods that will permit to obtain appropriate answers to questions relative to geo-environmental losses, potentials, transformations that can become operational and success criteria aiming at sustainable economical productivity. The sustainability notion is formulated so that it will integrate production relationships directly linked to the land and production costs regarded as logical operation aiming at the integration in some way of the environmental notion and the economical one. This zoning is part of a sequence of the Ecological Zonings, Economical Zoning, Ecological-economical Zoning, Design of Optimal Use of Hydrographic Basins- DUOT, and finally the Economical and Geo-environmental Certification of Hydrographic Basin – CQGB.

Zoning, economical productivity, ecology, sustainability, land use, hydrographic basin, agro-environmental planning.

The economical zoning - Ec-Z - of a territory has, without doubt, a dual aspect because it is economic and at the same time it must be based on an ecological zoning – El-Z - (Martins Jr. et al. 2006, b). This indicates the fundamentals of the economic activities, especially when it is developed in a close relationship with the use of land, bodies of water, ecosystems and natural vegetation.

Economically speaking, a zoning can be carried out under three aspects: (1) the ad natura zoning, ZE-Nan – in which the economic activities of any type are recognized in its possible realities within the conditions guided by ecological zoning; (2) the diagnostic zoning - ZE-Nd - that retraces the current economic reality of a territory and (3) the economical zoning of the economic potentialities and expansion - ZE-Np - of types: (a) potentialities not effectively discovered and/or described, (b) potentialities known but not explored, and (c) both situations (a) and (b), specially when technological progress can bring out new explicit possibilities. These are the three types of Ec-Z. Finally, it must be established an Integrated Model of Ecological-economical Zoning – EEZ, which is the integral model of the zoning aspects used to establish the cognitive basis for the planning and construction of elements for decision making.

The ecological – El-Z and economical zoning - Ec-Z, are necessarily based on multiple sciences, and are fundamental techniques for regional environmental planning as well as for economic and social planning. They are a set of “Interdisciplinary Approach”, which is appropriate for territory ordering.

It can be mentioned several current zonings that were implemented in the country, such as the EEZ of Minas Gerais, developed by a team from the University of Lavras, and the EEZ of the Maranhão State. Rio de Janeiro State has established laws which give directives on ecological zoning - Law 4,063 of 01/02/2003. In previous researches (MDBV Project, 2002-2004) (Martins Jr. et al., 1993 it, 1993-b, 1994 it, 1994-b, 1998) it was introduced the idea of “land classifications in homogenous areas with groups of n-order sub-basins” to be used as the effective multi-systems zoning methods in which the fundamental aspect is to classify the homogeneous areas for land management. Oliveira (2004) pointed out another fundamental aspect of the EEZ approach.

At the CETEC Foundation, together with the Federal University of Ouro Preto - UFOP, some projects have been relevant for the zoning methods development: ¾ MDBV Project (1992-1994); MPEH Project (1995-1997); CRHA Project (2002-2006); GZRP Project (2007-2008). With these projects it was developed a “triple system of regional and agro-environmental planning tools”. The first system is divided in three sub-systems ¾ the Ecological Zoning (El-Z), the Economical Zoning (Ec-Z), with its three versions, and the Ecological-economical Zoning (EEZ) based on references regarding the following sciences, engineering and subjects: ¾ Physical Economy (PE), Environmental Geology (EG), Structural Geology (SG), Lithology (Lt), Stratigraphy (St), Geotechnical Engineering (Gt), Pedology (Pd), Soils Aptitude (SA), Environmental Impacts (EI), Hydrology (Hy), Hydrogeology (Hg), underground Water Recharge Zones (WRZ), and Precise Areas of underground Water Recharge (PAWR) (Martins Jr. et al., 2006), Botany (Bt), Conservation Techniques (CT), Analysis of Impacts on the biomes (AI), Climatology (Cl), Exergetic Analysis (EA), Climate Changes Implications (CCI), Forest Engineering (FE), Electrical Engineering (EE), Agronomy (AE), Agricultural Engineering (AE), Economics (Ec), Interdisciplinary Logic (IL) and Artificial Intelligence (AI).

This triple System of Management Tools (SIGest) with zonings is introduced in a renewed manner, also in the development of a new knowledge branch proposed as Agrarian and Environmental Geosciences (AEG) (Martins Jr., 1998). Two other systems will be discussed in future articles.

The central question concerning the economical zoning, Ec-Z, refers to three fundamental aspects:

Economical zoning is its classification in ecological homogeneous areas, as a basis of the zoning process, and then the reclassification in economic basis starting from the ecological basis. This operation implies the integration of the totality of information that will form specific cognitive frameworks, and that assume and identify in fact the existence of environmental structures in Nature. In a complementary manner, it is the articulation of the identified structures with current and potential economical activities. Thus, all Ec-Z must be a set of zonings, as “multiple scene zonings”, considering the wide economic options as a function of the variation of the relationships of demands versus possibilities and supplies.

After the procedures of the initial discipline approach, the binomial - Ecological Zoning and Economical Zoning - constitutes, effectively, the third procedure together with the “Multidisciplinary and Interdisciplinary Approaches “, for the elaboration of essential products for the management, either rural as urban, in the basins territories.

A cognition system for the economic management must conjugate the three economical zonings - ZE-Nan, ZE-Nd and ZE-Np - in the scope of an economical theory, especially the Theory of Physical Economy.

Physical Economy can be defined in the Classical Economics context, although this concept is not very disseminated. The Classical Economics deals with the relationships among production, consumption, commerce of goods etc., using their own concepts such as: capital, value, income, opportunity cost, discount rate and others.

During the centuries, different subjects drew the economist’s attention: the availability of natural resources and the countries’ income, the capital accumulation, the human labor importance, the technology role in the production growth, etc. Adopting different models for each studied situation, the Classical Economics was not able to develop a model, general enough to include the several revealed trends. Demonstrating the economic variables in monetary terms, it ignored the production environment that represents the last barrier for human development in all its aspects.

Economists with perception of the production-environment relationships, as Georgescu-Roegen (1970) and Robert Ayres (1973), as well as Odum (1996) and others, have proposed to apply the laws of Physics, specially the Thermodynamic ones, to the economic phenomenon. Some models are already used to physically and economically optimize the energy conversion (vd. Economics-term) and to distribute the costs to co-products of an industry, among other objectives. The laws of Physics involved in the Economics are the laws of Energy and Mass Conservation (First Law of Thermodynamics) and the Increase of the Entropy (Second Law of Thermodynamics) in isolated system.

The concept of value associated to these laws corresponds to the exergy thermodynamic function ^[1], measured in Joule, than can be understood as “available energy”, resultant of the joint application of the basic laws mentioned. The exergy can be calculated for any substance, from the history of the chemical elements formation based on the Nernst Law (Third Law of Thermodynamics), which establishes that the entropy of pure crystalline substances is null at the absolute zero temperature (- 273,2°C or 0ºK).

In this methodology, the value aggregation is described by the exergy increase of the system, caused by the application of some mechanic work on this system. In the same way, the depreciation of any system is described by the exergy decrease, due to irreversible phenomena that occur inside the production system. The damage to the environment is directly evaluated by the exergy of the production and consumption wastes. On the other hand the convenience of recycling is made trough the comparison of the waste exergy with the product exergy, at some intermediary production stage.

It should be also pointed out that natural systems, which are open systems, also have exergy. Thus, some situations can be mentioned, such as: (1) water-driven exergy actually available for electricity production; (2) soils exergy, proportional to the relationships and demands of the agricultural plants as a function of the humus and the micro-nutrients; (3) the photosynthesis exergy in the production of natural products, as fruits, wood and biomass and (4) exergy of active principles in plants of the pharmacopeia, etc. Thus the exergy is in fact the energy factor convertible to chemical, natural and industrial work, and that can be converted into financial resources that are only symbolic resources of the production systems – natural and/or anthropogenic. In this sense, the exergy has an immediate relationship with the production efficiency, whatever its kind might be, as well as the products efficiency in generating work, so that work is an ample concept that may be, in this case, indicated in the form of “service for man”.

The exergy can also be understood, for example, as the energy part of the “information” contained in a chemical substance. However, in this case, the exergy would be the part of the information that can exert work on the environment, while environmentally speaking a chemical substance can also decompose its exergy, namely, the free energy that is part of the total internal energy, and can also, eventually, decompose its energy retained in the structure.

In general, the information regarding chemical substances is equivalent to all the internal energy contained in a substance, except those specific of atoms, excluding the nuclear fission. The total internal exergy is equivalent to the information, but it is not equal, as the form and information must be considered fundamental units of the Universe.

The zonings are procedures necessarily based on the Multidisciplinary and Interdisciplinary Approaches (Martins Jr., 2002). They must be developed with different methods, some of them already known and respected. Yet, there is no ample consensuses about the theoretical and methodological points of view, as well as about contents and semiotic. These zonings can be defined as a methodology with products that integrate practices and consensus among the several types of zoning carried out in the country; thus:

These definitions seem to be ample enough to contain the three varieties of proposed economical zonings. On the other hand, to normalize these concepts, it should be considered their predominant aspects of: (1) diagnosis; (2) conceptual recognition between different natural and cultural systems; (3) the specialist paradigms to make the diagnosis and finally (4) the reality representations.

When normalizing the concept this way, it can be perceived the amplitude of questions with which a zoning should be treated. Some of the questions are: (1) natural vegetation, agriculture and pastures zonings; (2) erosion, erosion processes and structures susceptible to it; (3) climate and plants/land/water relationships; (4) anthropic impacts; (5) agricultural projects variations in space and time; (6) productivity modelling; (7) transport and production sources systems and their impacts on natural systems; (8) systemically susceptible areas and areas with previous impacts; (9) demographic distribution and production sources; (10) existing logistic system for the location of activities, rural industries and cities as well as for transportation systems; (11) mining impacts and their situations; (12) conditions for control and/or exclusion of inputs use, etc. These examples indicate how far it is possible to go with the zonings procedures that, rigorously, can be as numerous as needed for perceiving, studying and planning the society actions concerning the environment.

For all intents and purposes Ec-Z zonings can be considered as part of a Interdisciplinary Approach - IA, which is indispensable for the sustainability planning, whatever the conditions may be in a given region. Anticipating this approach, it is necessary to continue the various classical studies of specialized sciences relative to the “Disciplinary Approach” and with the classical disciplinary cartography.

In hydrographic basins, the economic question focuses on both the potential and production of energy, agriculture, foresting, pastures, routes, logistic and rural industries, when they exist outside the urban areas and villages. Although urban areas are part of the hydrographic basins, these same areas deserve special treatment, for the obvious consequences on the surrounding area.

The economic question must be seen considering the following variables: (1) total planted area; (2) continuity index of the total planted area; (3) floral discontinuity index of the basin and its impact on the biome(s); (4) forests interconnection and massive forests index; (5) productivity in the several producing categories and agriculture fields; (6) capital mobilization; (7) producers indebtedness; (8) profits; (9) value aggregation in the geographic proximities; (10) inputs use; (11) environmental risks; (12) social inclusion in the different categories of producers; (13) use or non-use of effective process of soil conservation; (14) effective processes of water conservation; (15) successes of productions forms and measures that are ecological and economical sound; (16) non-used potentials and available potentials and (17) the effective energy production, among others. These 17 aspects allow the elaboration of economic models in which the relationships of gains per planted area are inserted, and where it must be computed all the ecosystem integrity loss that might lead it to the condition of environmental risk and to be inadequate for vegetal and animal life. Therefore, it is again considered an example of a logical equation to constitute some relationships of Ecology-economics with some variables (Table 1) (Martins Jr, 1998).

Table 1 – Table of logical, ecological and economic variables and logical operational symbols proposed (updated of Martins Jr., 1998).

Two logical equations are presented below, as examples of applications for the economical conditions analysis in a Ec-Z zoning. Those can be used to establish the development basis of a logical system of economical uses description for several conditions (seeTable 1):

Condition 1: Vs (>) [atp + Icatp + Idf] << Atbh_order-n is a possible diagnostic measure of the sustainability value expressed in exergy or in energy, which is the exergy reported to the solar constant, according to (Odum, 1996). (1)

It should be pointed out that the financial calculations are the ones adopted and known in economics, while in Physical Economy it is possible to move on with the whole economical accounting, with the measured and/or estimated exergy evaluations of the several productive phases, and only express all of it in financial units at the end, if it is necessary.

The economic aspects are multiple and can be combined in different manners. In this sense, it should be kept the ones that can be general enough to indicate the relationships between society and Nature concerning the renewable resources, or the non-renewable ones, in a way that they must be described in a Ec-Z . The sense of auto-sustainable development can be translated in a simple equation whose variables are the following (Table 2; in Martins Jr, 1998).

Table 2 – Variables of relationships between natural systems of renewable and non-renewable production and economic and logical variables (updated of Martins Jr., 1998).

§ renewable resource availability [Drr],

§ non-renewable resource availability [Drn],

§ extraction and transformation viability [Vet],

§ sustainability of involved ecosystems

§ [Se]

§ primary technology aggregation [Atp],

§ advanced technology aggregation [Ata],

§ transportation cost [Ct],

§ cost and great expense of energy [Cde]

§ aggregated value [Va]

§ market demand [Dm],

§ local impacts [il]

§ delayed impacts in the cycle of the natural-products-residues resource [it].

In a distorted sense, the generations from the 16^th to the 20^th centuries neglected a basic ethical principle, which is “the Earth does not belong to us, but to the future generations”.

Two notable examples in Brazil are the deforestation of the Vale do Paraíba do Sul in the Rio de Janeiro State for coffee plantations from the “Empire” to the “Old Republic” time, when these areas lost their agricultural potentials and the coffee production migrated to the São Paulo State. The result is a very poor land of difficult recovery, even though it is still possible to recover it. The deforestation of Vale do Rio Doce occurred without learning lessons from the past, for the main interest of the metallurgic companies in this hydrographic basin and in other places, in the 1980 decade.

The environmental prices aggregated to the current products should, in fact, start to aggregate the environmental liabilities caused by the companies that, currently, owe the Nation a solution for this problem. How to aggregate to the industrial microeconomics and to social macroeconomics the real cost of this restoration, without turning an industrial process to a non-viable one? However, the problem exists and does not have a logic that associates mitigation with social-economic interests. As long as the experience demonstrates it, the economic process will be unviable for the future centuries, so that the ecosystems that remain will inexorably progress to irreversibility.

What actually occurred is that the implemented industrial processes in the Vale do Rio Doce were not evaluated at all regarding the environmental cost, ending in its current ecological devastation. How to effectively aggregate this cost to the environmental policy and to the industrial price policy through two principles, the taxes and the current quality control? Would this be a lost cause?

Let us consider the aspects bellow as a criterion that must be used as a part of a formal equation of Eco-sustained viability of enterprises. The factors that indicate the Eco-sustained viability of exploration and/or production of any resource in an Eco-sustained perspective are the following (Table 3).

Table 3 - Factors of an economical and ecological viability of the productive activities in relation to a hydrographic basin (updated of Martins Jr., 1998).

§ resource access,

§ resource availability,

§ market value,

§ demand and supply relative to the resource,

§ purposes for its usage,

§ ethical justification of the purposes,

§ impacts on the geographic area of extraction,

§ conservation of the systematically important areas,

§ extraction, transportation and transformation values relative to the possible impacts on the environment,

§ problems relative to the environmental landscape degradation,

§ specific impacts on waters,

§ availability or not of clean technologies,

§ competitiveness as a function of the cost of the most efficient and clean technologies,

§ social gain trough environmental taxes, and social investments,

§ relation with the hydrographic basin management in the condition of payer-user that pollutes or does not pollute,

§ possible aggregation effect of population increment in the surrounding area of the production or extraction.

These are some of the aspects of economical-social order that influence the perspective of the relations of the Ecology and Economics in the case of natural resources extraction, as well as in the case of implementation of industries and forest agro-pastoral projects. In these cases it is possible to occur excessive demand of water quantity, which can lead to an environmental stress in the hydrographic basin.

This concept implies that in every territory we will find areas with vegetation in several altered states, agricultural planted areas and/or with mono-specific woodlands and also areas that can be understood as to be replanted to reach ecological and/or ecological-economical requirements. To plan the regional ordering of the land to estimate the total area to be replanted, considering that the geo-ecological interests between rocks/geoforms/soils/agricultural areas and the economic interests are guaranteed, have as a fundamental equation:

S S_F = S_BH ± S_Rs - S_Gi - S_Si - S_CVr ± S_Ad ± S_Av ± S_P - S_U - S_OE - S_Ca (3)

The economic question is also based on the ecological questions or on adequacy of plant/water/soils/climates-microclimates in a manner that the specific relationships between biomass production for energy - BE - and biomass for feeding - BF – are placed as critical in the Country.

Effectively, the direction to the options on the areas that can be planted for these two situations is currently under the focus of national and international economic and political interests. The fact that the population grows in the planet, that more people can eat better, that the international capital acts in a speculative manner regarding the food when facing the critical pressures of the prices of the energy sources of greater exergy (as petroleum), lead to the fact that the options for lands must obey the following general equation:

S S_pAE º S_BH - S_Ad _traditionals - S_CVr - S_Ca + ( _{eventual fraction} S_Ad + S_P + _{areas of semi or total barn for the cattle} S_stEg << S_P) - S_pag (4)

S S_pAE - total area that can be planted for the energy production of biomass and feeding production

It is clear that the ecological zonings - El-Z and the economical zoning - Ec-Z serve as a base for integrating ecological-economical zoning EEZ. As showed previously, there are three types of Ec-Z, and thus the choices and manners of presenting them will have a more interesting use according to the economical questions to be considered, and that can be treated better in each method of representation. The representation of total economic applications constitutes a legitimate product for the environmental and economical management of the biomes and hydrographic basins.

Among questions such as reforestation, erosion, highways, canals and hydro ways construction, production of hydroelectric energy, etc., there are several combinations of the three Ec-Z based on the El-Z zonings, including several discipline mappings, that can articulately give us important information to understand the questions of the relationships between human activities and undertakings with the environment. This focus includes the the natural structures as well as the geological processes in their ample sense.

The Economy, if represented by tables, diagrams, organization charts, flowcharts, in UML (unified modelling language) and in relations to the Natural systems, allows the maps to be auto-clarifying, as long as the relationships are shown with their own semiotic. Tables 1 and 3 show some forms of indicating economic questions with the use of logical equations. The equations (3) and (4) open especially the logical field of questions for the “Design of Optimal Use of Hydrographic Basins” (DUOT^®), design in which the zonings become a general drawing, ideal normative about a territory totality, conserving all the sustainability conditions. To these several equation types, it should be added the Physical Economy analysis with the exergetic analysis, or with the system entropy analysis, with the materials cycle, from production to discarding, as a step to organize a general framework of all the actions of conservation, preservation, mitigation and optimal use of a hydrographic basin land.

The “geo-environmental/economical” thematic leads, after carrying out the El-Z and Ec-Z, to a new step that should be followed for the ecological-economical management process of a territory and of the relationships between man/Nature, or, the integrated Ecological-economical Zoning – EEZ, from the ample methods here discussed.

* CETEC Foundation. Av. J.C. da Silveira 2000. Horto. 31,170-000 Belo Horizonte, MG. paulo.martins@cetec.br; Phone.: +55 (31) 3489-2250; FAX +55 (31) 3489-2227.

** Federal University of Ouro Preto, Mines School, Geology Department. Post-graduation Program.

*** Economy & Energy Organization (OSCIP): Rua Jornalista Jair Silva, 180, Bairro Anchieta, 30310-290, Belo Horizonte, MG, Phone.: +55 (31) 3284-3416;

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^[1] The exergy variation of a system, defined as the maximum work that can be obtained when taking a thermodynamic system from its current state, described by internal energy and the system entropy, to the state of balance with the ambient is given by the equation E = U - T₀S, being T₀the ambient temperature. The exergy in the state of balance with the ambient is null.

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