Daniel Rodrigues de Lira

Stone and Sand Ruins in the Drylands of Brazil: The Rustic Landscapes of Catimbau National Park

Catimbau National Park (CNP) is the only one in Brazil entirely circumscribed by the semi-arid climate and the Caatinga biome of the Northeast region of the country. It is situated in the state of Pernambuco and comprises a set of sandstone landscapes of unique scenic beauty as well as holds important records of archaeological, biogeographical and geomorphological history of the central drylands of the country. The area displays a mosaic of natural landscapes developed on sand covers of the borders of Jatoba sedimentary basin, an important regional geologic feature that was severely deformed by post-Cretaceous tectonic movements following the break-up of Gondwana continent and the final opening of the South Atlantic Ocean . The occurrence of table-like buttes and uplifted homoclines, some in excess of 1,000 m in elevation, favours the development of moister and cooler environmental conditions, which are reflected in the local ecology by means of vegetation refuges and enclaves that differ significantly from the prevailing thorn-scrub xerophytic formations of the Caatinga. Concentration of drainage network towards the base and knick-points at the abrupt sandstone escarpments favours the formation of seasonal swampy areas and lagoons , which are rare natural features within this dryland region of the eastern seaboard of South America.

Avaliação do papel da drenagem na elaboração de feições geomorfológicas no município de GOIANA - PE

Este artigo apresenta uma analise da influencia da rede de drenagem no modelado da superficie terrestre e na evolucao geomorfologica no municipio de Goiana, Estado de Pernambuco. Foram aplicadas tecnicas de Modelagem Numerica do Terreno para estabelecer diferencas entre os padroes de drenagem, de relevo e de solos, buscando identificar areas morfogeneticamente distintas. Foram identificados quatro padroes de drenagem: 1- padrao pinado, orientado para sudeste e relacionado as colinas dissecadas; 2- padrao paralelo, orientado para nordeste, com formas tabulares dissecadas; 3-paralelo e subparalelo, orientado para sudeste, com forma tabular; e 4- paralelo, direcionado a leste, forma tabular. Esses padroes sao fortemente influenciados pela presenca de feicoes morfotectonicas de grabens e horsts.