Paisagens físicas da Guanabara

Resumo

In the present work the author attempts to treat the different com='ound elements of the physical landscape in a systematic and synthetic manner. He divided the previous work in some different compound elements as climate, geological structure, forms of relief, kinds o f vegetation, and soils.

            In a small, space of 1 356 km he identified some kinds of climates of the group A and C according a classification made by Koppen.

            The geological structure is characterized by outcrops in the mountainous parts - mainly granite and gneiss, and sedimentary rocks in the lower parts. From the point of view of the historical geology, the Precambrian terrains prevails in the massifs and quaternaries in the plains.

            The geomorphology is characterized by three mountainous massifs and parts of plain. These mountains were formed by epirogenisis in the beginning of the terciarian, and they composed the part o f the great. plain. In the Precambrian, these rocks supported the Laurencian diastrophism and still our day on see the directions lead in the doubled rocks.

            The typical formations like the "sugar loafs" constitute other remarkable feature of the morphology in the Guanabara's relief.

            The origin of Guanabara's bay constitutes a great controversial subject between the geomorphologists.

            The initial vegetable cover it was of forests, and a little space on field in the zone of Santa Cruz lowland. Now the forest vegetation was demolished in its great part. Moreover, we must to cite the marshy area in the place wh2re exists the saline influenced by oceanic waters.

            The soils constitute other important feature of the physical landscape. In the space of macifs the orange and red clays soil detache, while in the plant areas a variety is great. In the arenaceous fillets situated in the spits the soil are very siliceous, and both in the inner of the Sepetiba and Guanabara's bay the coils are constituted by coze (or mud) deposits. For these clayey soils in the lowlands, these are coming of transported material of the surrounding areas situated in the higher altimetrical position.

            The Anuário Estatístico do Estado was one of the most important informative book that informs the quantitative data with precision.

            According the heading the author searches to present the different features of landscape with reports and illustrations which complement the text.

            Sometime, the photographs were largely commented to provide a major subsidy of the landscape diversification.