• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • Tagged with
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Foramin?feros como ferramenta de estudo na geologia ambiental do estu?rio do Rio Potengi e da plataforma interna, RN, Brasil

Farias, Cristiane Le?o Cordeiro de 16 November 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T19:35:28Z No. of bitstreams: 1 CristianeLeaoCordeiroDeFarias_DISSERT.pdf: 6033643 bytes, checksum: 958aa1ad7170e354d48b68819bbeaf94 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-28T23:04:10Z (GMT) No. of bitstreams: 1 CristianeLeaoCordeiroDeFarias_DISSERT.pdf: 6033643 bytes, checksum: 958aa1ad7170e354d48b68819bbeaf94 (MD5) / Made available in DSpace on 2016-07-28T23:04:10Z (GMT). No. of bitstreams: 1 CristianeLeaoCordeiroDeFarias_DISSERT.pdf: 6033643 bytes, checksum: 958aa1ad7170e354d48b68819bbeaf94 (MD5) Previous issue date: 2015-11-16 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Os estu?rios tem grande import?ncia como abrigo e ber??rio natural de animais marinhos, prov?m peixes para o homem,sustenta a cadeia alimentar, controla as a??es erosivas e alagamentos, atua nosistema de filtragem natural da polui??o e purifica??o do ar. O Rio Potengi temsido afetado por diversos fatores antr?picos ao longo dos anos, com v?riosdesastres ambientais que mataram peixes, aves e outros animais. Para analisar asitua??o recente do estu?rio do Rio Potengi, foram coletadas 42 amostras, 18 emOutubro/2011 ao longo do Rio Potengi e sua foz, e 24 em Janeiro/2012, inclu?mosa plataforma interna. An?lises univariadas (?ndices ecol?gicos) e multivariadas(PCA, MDS, CLUSTER e BIOENV) foramaplicadas ? matriz dos dados biol?gicos de foramin?feros e abi?ticos (CaCO3,salinidade, profundidade, temperatura e granulometria). Os resultados mostram a domin?ncia deforamin?feros oportunistas A. tepida,B. striatula, Q. patagonica e Q. milettiespecialmente nas regi?es pr?ximas ?s fazendas de carcinicultura e ao esgoto doCanal do Baldo em ambientes de granulometria fina, e Q. lamarckiana indicadora da penetra??o da cunha salina e ambientesde alta hidrodin?mica associada a sedimentos de areia grossa a muito fina. A presen?a de esp?cies caracter?sticasmarinhas H. boueana, E. discoidale, P. atlanticum, T. earlandie T. gramen na Foz do Rio Potengi ena plataforma interna indicam ambientes de altas salinidades. A ocorr?ncia dealgumas esp?cies tolerantes ? baixa salinidade como T. inflata e T. squamatano Canal do Rio Potengi sugerem que provavelmente devem ter sido transportadosdo manguezal pr?ximo ? foz do Rio Potengi para as regi?es de plataformainterna, sugerindo que o contribuinte fluvial ? capaz de exportar organismos de?gua doce preferivelmente em dire??o sul do que em dire??o norte. / The Potengi River estuary has been affected by various anthropogenic factors over the years, as periodic dredging, industrial and domestic waste, traffic and other factors, causing various environmental disasters, including the notorious ecological accident in July 2007, which covered the municipalities of S?o Gon?alo do Amarante, Maca?ba and Natal. Foraminifera serve as viable study tools in these environments; they are able to identify ecologically stressed environments, pointing out hydrographic changes and depositional environments in estuaries. The necessity to check the differences in environmental gradients in places anthropically impacted in Potengi River and adjacent inner shelf through species of foraminifera, and, the responses of these organisms to physical, chemical and geological factors is to provide baseline in the diagnosis of environments. The results show the dominance of opportunistic Ammonia tepida, Bolivina striatula, Quinqueloculina patagonica and Q. miletti especially in regions close to shrimp farms and Baldo Channel sewage in fine grain environments; and Q. lamarckiana indicates penetration of the saline waters in Potengi River. The occurrence of low-salinity tolerant foraminiferal species typical of mangrove environments as Trochammina inflata and T. squamata in Potengi River Channel suggest they probably could have been transported from mangrove area near the Potengi river mouth to the inner shelf regions. These findings suggest Potengi River is able to export mixohaline and mangrove organisms to inner shelf. Two distinct environments were observed, the outermost area is more influenced by marine influence and the innermost area is less influenced. Calcareous and agglutinated species dominate Potengi River, while mouth and inner shelf areas are dominated by calcareous, agglutinated and porcelaneous species, which are typical of highly saline and hydrodynamic environments and the contributive factors that controls foraminiferal distribution were balance of marine and freshwater currents, grain size, availability of CaCO3 and organic matter.

Page generated in 0.125 seconds