O Planalto Central e o problema da mudança da capital do Brasil

Resumo

The "Comissão de Estudos sobre a Localização da Nova Capital do Brasil" (Commission of Studies for the Localization of the New Capital of Brazil) organized in 1947 two geographic expeditions to the "Planalto Central" (Central Plateau). The first one, headed by Prof Francis Ruellan studied in detail the eight zones previously selected by the Commission, with the purpose of indicating adequate sites for the localization of the capital. The second, headed by Prof Fábio de Macedo Soares Guimarães and under the scientific guidance of Prof. Leo Waibel, studied the Central Plateau, having in view the problem of the location of the capital and the type of adequate sites. This preliminary report refers only to the under takings of the second expedition.

            The expedition, composed of nine technicians, worked in the field from July 4 to September 22, having traveled. some 10,000 kilometers, covering an area of 200,000 square kilometers. The geographic study comprised important details regarding general aspect and geologic structure, climate, drainage, vegetation, soil, population, types of economy and use of the soil, transportation and communication facilities, etc.

            As regarding the general aspect, the region is formed by an extended plateau, with altitudes varying up to 1,000 meters. This plateau is run through by valleys closely set together, being thus subdivided into almost perfectly horizontal parts locally called "chapadas”. The geologic structure ls relatively simple: a basement of old crystalline rocks (gneiss, micaschists and quartzites) formed of strongly bended or inclined layers, partially covered with mesozoic sediments (chiefly sandstone), in horizontal or nearly horizontal layers. In the Southern part found layers of basic effusive racks, basalts and diabases and wich are called "trapps". To the South-east volcanic tuffs can be seen. The Central Plateau is an extensive, partially dissected peneplain, the surface of which cuts indifferently into the rock layers.

            The climate is tropical but softened by the altitude, and there are a few upper valleys where frosts can be observed Rains are copious and there are two distinct seasons: the rainy and the dry. The latter season lasts from April or May until August or September. The upper regions are generally free from malaria.

            The rivers of the plateau are perennial and fed with subterranean water. The valleys are deeply cut and the "chapadas" dry.

            The vegetation is predominantly formed by grasslands; there are also a few forested areas, of which the following three are very important: "Mato Grosso de Goiás", "Mata da Corda" and the forests of the Paranaíba and Rio Grande, valleys The soil of these forests originate from basic rocks and are more fertile (old eruptive rocks, volcanic tuffs and "trapps"), whereas the grasslands ate indicative of a poor soil.

            The population is generally vet y scarce, less than 5 inhabitants pet square kilometer However, in the forest areas the population is denser, with mote than 5 and even exceeding 15 inhabitants pe1 square kilometer.

            While only extensive cattle breeding is being practiced in the grassland zones, agriculture as well as intensive cattle bleeding are concentrated in the forested areas. Besides rice, which is the principal crop, coffee, maize, beans and cotton are also cultivated. Although the large properties predominate, there are also smaller properties in the forest zones In "Mato Grosso de Goiás" and in the Paranaíba woods there are two pionee1 zones which attract a lat ge numbe1 of colonists, especially Brazilians.

            As regarding the idea of a good location, the expedition is of the opinion that the principal functions of a capital ate not colonization and strategy but administration and politic.

            In connection with the administrative function, the ideal location would be the demographic center. At present this center is situated in the São Francisco valley, to the Northeast of Pirapora, but the tendency of its movement is to the South-west, towards the source of the Paranaíba river, towards "Mata da Corda".

            The most important role of a capital as a political center is to unify the country. To achieve this, its location should allow easy communication with the various regions of the country, especially with those which are most populated and developed. Therefore, the best location would be the South-east of the Central Plateau, in "Mata da Corda", on the boundary of the spheres of influence of the States of São Paulo and Rio de Janeiro and near the town of Patos de Minas Communications maybe easily established from this point with the Southern, Eastern and Central-western regions, and also with the Northeastern part of Brazil, through the São Francisco valley.

            After the best location had been chosen, the eight zones indicated by the Commission were classified in accordance with their distance from that location.

            The Expedition then examined the conditions which an adequate site must offer as regarding following details: topography, climate, water supply, proximity of woods, hydraulic power, building materials, nature o f the subsoil and attractive scenery.

            Regarding topography and climate, it is easy to find adequate sites in the upper parts of the valleys.

            The supply of water presents a few difficulties for, as the capital must be located on an elevated area, it will be necessary to use pumps which would requite cheap and abundant electric power.

            The proximity of woods is essential so that provisions may be easily supplied to the capital.

            As regards the hydraulic power, it is only in the "trapp" zones in the South where large and numerous waterfalls are found.

            Adequate sites for the supply of construction materials and convenient in relation to the nature of the subsoil are also easily found; but attractive sceneries can only be observed in the vicinity of the forests, as the grassland zones me extremely monotonous.

            Taking into consideration all these conditions essential to the suitable localization of the capital, the Expedition selected the three following areas which, in a decreasing order, are the most favorable:

→ 1- C zone or Uberlândia/Tupaciguara;

→ 2 - D zone or Patos de Minas;

→ 3 - F zone or Goiânia/Anápolis.

            These areas are in the neighborhood of the three large forest zones The first is the most convenient as regards water supply and hydraulic power.

            The Expedition recommended the carrying out of detailed studies in those three zones, especially the organization of accurate maps and research made by experts, as well as hydrologic studies thus enabling the final choice of the best location for the new capital.