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Mangroves are key ecosystems which respond to global changes in tropical and subtropical regions worldwide. We describe late Holocene mangroves that established close to the southernmost limit (28°S) for this type of ecosystem in South America. Our findings are based on a C dated core obtained from Babitonga Bay, Santa Catarina State, Brazil (26°12′S, 48°33′W). Analysis of palynology, sedimentary facies, isotopic and elemental data shows that mangrove establishment took place ~500 yrs. B.C.E., following an increase in humidity, and expanded further during the Roman Warm Period and at the end of Dark Age Cold Period. Mangrove and precipitation proxies records appear to be sensitive to rainfall patterns imposed both by the expansion/retraction of the Intertropical Convergence Zone and also the interaction with the South Atlantic Subtropical Anticyclone which affects coastal region due to sea surface temperature variations., The authors thank the Coastal Dynamic Laboratory (LADIC-UFPA) , C-14 Laboratory of the Center for Nuclear Energy in Agriculture (CENA-USP) , University of Joinville (UNIVILLE) and Radiocarbon Laboratory (LAC-UFF) for all infrastructure and support. We also thank three anonymous Reviewers and Prof. H. Falcon-Lang for their constructive comments. The first and third author thanks Brazilian Council for Technology and Science-CNPq for fellowship (process 131813/2016-1 , 165911/2015-8 and 305074/2017-2 ). This study was financed by CNPq ( 445111/2014-3 , 405060/2013- 0 ) and FAPESP ( 2011/00995-7 , 2017/03304-1, and 2020/13715-1 ). This study also was financed in part by the Coordenação de Aperfeiçoamento de Pessoal Nível Superior – Brazil (CAPES) – Finance Code 001 .

Made available in DSpace on 2020-12-12T01:30:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Temperature influences the global distribution of mangroves, and global warming may be causing a poleward mangrove expansion. Sedimentary features, pollen, and isotopes data from six sediment cores, as well as 14C datings, indicated a marine transgression during the Holocene, and it contributed to the expansion of tidal flats occupied by saltmarshes. Environmental conditions suitable for mangroves development occurred on the study site during the Holocene, but, according to 210Pb and 14C dating, the establishment of mangroves mainly represented by Laguncularia trees only began between ~1957 and ~1986 (AD) on the studied tidal flats. Spatial-temporal analysis, based on satellite and drone images, revealed a mangrove expansion of ~10 ha in the study area between 2003 (96.1 ha) and 2019 (106.1 ha). Nowadays, in the study area, saltmarshes, mainly characterized by Spartina and Acrostichum, are sharing tidal flats with mangroves, represented by Laguncularia (≤5 m tall) and Avicennia (≤11 m tall). Probably, the absence of mangroves during the Holocene, followed by their establishment and expansion during the Anthropocene in the subtropical zone, is associated with a migration of the austral mangrove limit into the temperate zone, caused by the gradual increase in winter temperatures. This process may be related to a poleward mangrove migration since the late Holocene, caused by a natural Holocene global warming. However, the industrial-era warming must have intensified the mangrove expansion into temperate zones. Graduate Program of Geology and Geochemistry Federal University of Pará, Av. Perimentral 2651, Terra Firme University of São Paulo CENA/14C Laboratory, Av. Centenário 303 Federal Institute of Pará, Av. Alm. Barroso, 1155, Marco Instituto de Geociências e Ciências da Terra Universidade Estadual Paulista Júlio de Mesquita Filho-UNESP University of São Paulo CENA/Stable Isotopes Laboratory, São Paulo Instituto de Geociências e Ciências da Terra Universidade Estadual Paulista Júlio de Mesquita Filho-UNESP FAPESP: 2011/00995-7 FAPESP: 2017/03304-1

Globally, mangroves are expected to move inland as sea-level rises. However, local characteristics mainly related to mangrove structure, geomorphology and coastal hydrodynamics may change the mangrove response to sea-level rise. The most useful evidence to support projections for the future likely comes from mangrove history reconstruction corresponding to past sea-level changes. This study characterized modern (1985–2018 CE) and past (

Generally, palaeoenvironmental interpretations consider only allogenic processes, when autogenic factors may have a strong influence on proxies of stratigraphic sequences. For instance, the Holocene history of the vegetation along the southern littoral of the State of Bahia in north-eastern Brazil is characterized by mangrove dynamics controlled by allogenic processes. However, over smaller timescales (~700 years), autogenic processes may have controlled vegetation dynamics and hence observed pollen distribution. This work proposes tidal channel dynamics as one of the main cause for changes in pollen assemblage along the studied stratigraphic profiles during the last centuries, based on sedimentology, pollen and elemental analysis (δ13C, δ15N and C/N) and radiocarbon dating of sedimentary organic matter from two cores sampled from an abandoned meander and a tidal flat at the mouth of the Jucurucu River. One core was sampled from a mangrove formed during the past ~550 cal yr bp. Another core recorded sediments in a varzea forest (swamp seasonally and permanently inundated by freshwater) located ~2.7 km from the current shoreline, which displayed a maximum age of ~680 cal yr bp. Two facies associations were identified: tidal channel (A) and tidal flat/oxbow lake (B). This work proposes allogenic processes as the main driving forces controlling the wetlands dynamics at the studied site during the Holocene. However, our data also reveal that part of the changes in vegetation over the last ~700 years reflect tidal channels and tidal flats development, which represent autogenic processes. The change in timescale analysis from the Holocene to recent centuries may have weakened the influence of allogenic factors. However, this needs interpretation with reference to the spatial scale of the depositional environment as the larger the depositional system analyzed, the stronger the influence of autogenic processes on stratigraphic sequences over longer timescales. Copyright © 2017 John Wiley & Sons, Ltd.

The aim of this paper is to evaluate the compatibility between the Holocene relative sea-level (RSL) curves proposed for the Brazilian littoral and mangrove dynamics along a fluvial valley in the state of southern Bahia. This was done integrating geomorphological, sedimentological, palynological, and stable isotopic data from two cores collected at the mouth of the Jucuruçu River and at a site 23 km inland, near the city of Prado, northeastern Brazil. Core PR07, sampled from a fluvial plain at about 4.5±1 m above the RSL, reveals mangrove pollen (5–20%) and estuarine/terrestrial organic matter (δ13C=~–25‰, C/N=7.3–67) between 4.5 m (~7400 cal yr BP) and 1.75 m depth (~5350 cal yr BP). Core PR11, sampled from a mangrove tidal flat, also revealed mangrove pollen taxa (5-28%) since 660 cal yr BP. Core PR07 indicated absence of mangrove pollen and increase of sedimentary organic matter sourced from terrestrial C3 plants (δ13C=~–27‰, C/N=22–159) during the last 5350 cal yr BP. Probably, the changes in vegetation and sedimentary organic matter identified in core PR07 were caused by the combined effects of the RSL fluctuations, with a highstand at about 5350 cal yr BP of 2.7±1.35 m, and changes in fluvial discharge.

This study demonstrates the usefulness of palynofacies as a tool for characterizing the origin, transport, and settling of particulate organic matter preserved in fluvial plain sediments and its integration with diatoms for inferring past depositional environments. Palynofacies, diatoms, and organic geochemistry (S, C/S) data from a sediment core (PR07) collected from the Jucurucu River valley in coastal southern Bahia, northeastern Brazil were used to better understand ecosystem changes that occurred in the region during the last ~7.5k years. Elemental values (S: 0.15–5.9%; C/S: 0.12–41.5) suggest marine and fluvial influences in the valley during the Holocene, and organic matter was derived from freshwater and marine phytoplankton. The presence of heterolithic deposits, brackish/marine diatoms, predominance of amorphous group, non-opaque phytoclasts, pyrite crystals, and marine microfossils suggests that a tidal flat formed during a mid-Holocene sea-level highstand. A fluvial plain developed in the last 5k years, due to marine regression and an increase in fluvial sediment supply to the region.

The Atlantic Rainforest, covering the area from northern Espirito Santo to Southern Bahia states, has been considered as a stable forest during Pleistocene Glacial times. Aside from modelling and phylogenetic studies, this hypothesis has never been tested with empirical, fossil pollen, paleo-vegetation data. By using palynology, radiocarbon dating, and carbon and nitrogen elemental and isotopic analyses of organic matter, we reconstructed the vegetation dynamics and inferred climatic changes since the Late Pleistocene in the centre of this global biodiversity hotspot. Our results show that the forest biome was resilient to Last Glacial Maximum - LGM conditions, but that the floristic composition differed from that of today. Since the late glacial, the floristic composition of the dense forest changed from cold- to warm-adapted taxa. Structural, as well as floristic, changes occurred during drier conditions of the early and middle Holocene, with an opening of the forest, providing insights into the type of vegetation impacts that might be expected under predicted future drought.

The aim of this paper is to reconstruct an 11,000-year history of depositional environmental change in southeastern Brazil, based upon the integration of particulate organic matter and stable isotope (C and N) data from a 136-cm sediment core from Lake Canto Grande. These proxies are used to explore the evolution of terrestrial and marine influence on the lake. Isotopic (δ13C: −27.87‰ to −31.9‰; δ15N: −0.07‰–4.9‰) and elemental (total organic carbon - TOC: 0.58%–37.19%; total nitrogen - TN: 0.08%–1.73%; C/N: 0.3 to 54.7) values recorded in Lake Canto Grande suggest that the sedimentary organic matter was derived from mostly C3 land plants and freshwater phytoplankton. Particulate organic matter and cluster analyses distinguished four associations characterized by the predominance of amorphous organic matter, followed by phytoclasts and palynomorphs. These results indicate two different phases of lake evolution. The first phase (136 - 65 cm; ∼10,943 cal yr. B.P. to ∼8529 cal yr. B.P.) is recorded by sand layers interbedded with mud, which contain amorphous organic matter (AOM, 45–59%) and phytoclasts (opaques - OP: 6–18%; non-opaques – NOP: 17–23%) which indicate a floodplain area. The second phase (65–0 cm; ∼8529 cal yr. B.P. to ∼662 cal yr. B.P.) comprises mud, AOM (68–86%) and palynomorphs (PAL, 8–16%) related to lake establishment comparable to modern conditions. Thus, characterizing particulate organic matter, in combination with stable isotopes, proved to be invaluable proxies for lacustrine paleoenvironmental change through the Holocene.

Particulate organic matter in sediments constitutes a valuable proxy for paleoenvironmental reconstructions. A 192 cm lacustrine sediment core (~ 7521 cal yr. B.P.) from the northern coast of the State of Espirito Santo, southeastern Brazil, was radiocarbon dated and then analyzed for palynofacies, stable isotopes (C and N), and grain size. The values for total organic carbon – TOC (1.91% to 20.89%), total nitrogen – TN (0.08% to 1.1%), δ13C (− 27.10‰ to − 29.01‰), δ15N (1.92‰ to 5.09‰) and C/N (12.87 to 50.11) suggest predominance of C3 plants and changing mixtures of terrestrial and aquatic organic matter in the sediments. Palynofacies and cluster analyses were used to identify four palynofacies associations that reflect different phases in the Lake Macuco evolution. Palynofacies 1 (192 to 106 cm, ~ 7521 cal yr. B.P. to ~ 7054 cal yr. B.P.—interpolated age) is characterized mainly by amorphous organic matter (AOM), non-opaque phytoclasts (NOPs), mangrove pollen grains (Rhizophora sp. L. 1753 and Avicennia sp. L. 1753), and foraminiferal test linings. Palynofacies 2 (106 to 65 cm, ~ 7054 cal yr. B.P.—interpolated age to ~ 4847 cal yr. B.P.) is dominated by NOPs and AOM, with an increase in the values of mangrove pollen grains relative to Palynofacies 1. Both palynofacies reflect marine and fluvial influences in a depositional environment related to the development of an estuarine system during the mid-Holocene transgressive stage. Palynofacies 3 (65 to 27 cm, ~ 4847 cal yr. B.P. to ~ 3800 cal yr. B.P.—interpolated age) comprises high abundances of fluvial elements (NOP and opaque phytoclasts—OP) and low values of AOM. The depositional environment is interpreted as being an estuary during the marine regression, with the displacement of the estuarine basin and mangroves towards the sea. Palynofacies 4 (27 to 0 cm, < ~ 3800 cal yr. B.P.) is characterized by the predominance of AOM and NOP, increase in the values of freshwater algae, and no evidence of marine influence. This last phase reflects the beginning of the establishment of Lake Macuco and floodplain of the Barra Seca River under conditions similar to the present-day.

A 190 cm mangrove sediment core from the Ilha do Cardoso State Park, State of Sao Paulo, southeastern Brazil was analyzed for pollen, diatoms as well as carbon and nitrogen isotopes. The goal was to determine the dynamics of the coastal terrestrial/aquatic ecosystems, vegetation history and climate change in this region of the Brazilian Atlantic rainforest, during the Late Pleistocene and Holocene. The values for total organic carbon—TOC (from ~ 3 up to 40%), C/N ratios (from ~ 10 up to 130), and δ15N (~ 0 to > 8) are associated with well preserved aquatic and terrestrial organic matter and possibly influenced by nitrogen cycling (e.g., denitrification) that caused 15N enrichment between > 40,000 cal yr B.P. and ~ 23,000 cal yr B.P. Depleted δ13C values (~ -28.0‰) are also observed and indicate the predominance of C3 plants. During this time interval, the pollen analysis reveals the presence of the genera Ilex, Alchornea, Weinmannia, Myrsine, Symplocos, Drimys and Podocarpus on a site currently occupied by mangrove vegetation. These data suggest that in the past prevailed a colder and more humid climate than today, with a low relative sea-level. From ~ 23,000 cal yr B.P. to ~ 2200 cal yr B.P. a sedimentary hiatus likely occurred, related to an erosive event associated to the post glacial sea-level rise. Since at least ~ 2200 cal yr B.P., sediments are marked by relatively low C/N ratios (from 2 to 27), exhibit more enriched δ13C (from ~-26.0‰ to − 24.0‰) and δ15N (up to ~ 7) values and are characterized by the presence of marine diatoms. This indicates the return of the marine coastal line to its current position, and consequently the development of mangrove.

This study was carried out in a continental Atlantic Forest located in the southern region of Sao Paulo State, southeastern Brazil. The aim of the study was to evaluate the vegetation dynamics in ∼70 km forest ecosystem transect that occurred during the late Pleistocene and Holocene in this region, using the stable carbon isotopes (δ 13 C) analysis on soil organic matter (SOM) and the 14 C dating of buried charcoal fragments and the humin fraction of SOM. The isotope data (δ 13 C) of SOM in the deeper horizons, indicating the presence of more open vegetation than the present, with a probable mixture of C 3 and C 4 plants, suggesting the presence of a drier climate in the period of ∼20 ka to ∼16–14 ka BP. From ∼16 to 14 ka BP to the present, a significant predominance of C 3 plants was observed, indicating an expansion of the forest, probably associated with the presence of a more humid climate than the previous period. The results indicated the presence of open vegetation during the late glacial, probably associated with a drier period, also observed in other regions of Brazil. The Atlantic Forest ecosystem seems to have developed at least since the early Holocene in southeastern Brazil.

Um testemunho de 12 metros de profundidade e idade de ~47260 anos cal AP na sua base foi coletado na planicie deltaica do litoral norte do estado do Espirito Santo. Esse trabalho teve como principal objetivo a caracterizacao do conjunto de fitolitos, auxiliado pelas facies sedimentares, dados isotopicos (C e N) e datacoes 14 C para reconstituir o paleoambiente. Os valores de carbono orgânico total - COT (0,16% a 3,28%), nitrogenio total - N total (0,01% a 0,09%), δ 13 C (-4,25‰ a -28,06‰), δ 15 N (-6,19‰ a 15,75‰) e da razao C/N (7,8 a 99) mostraram em linhas gerais que a materia orgânica sedimentar foi originada a partir de fitoplâncton, e da mistura de plantas C 3 e C 4. A analise de fitolitos foi efetuada ao longo de 1,50 metros do perfil, e a partir dos agrupamentos por similaridade foi possivel o estabelecimento de tres intervalos que refletem mudancas na vegetacao e provavelmente no clima a partir de ~7589 anos cal AP. No intervalo 1 (~7589 anos cal AP a ~5441 anos AP – idade interpolada), a assembleia fitolitica e os indices estatisticos de fitolitos calculados refletem uma vegetacao composta pela mistura de arvores e gramineas C 3 e C 4 , semelhante e/ou comparavel a vegetacao de restinga, provavelmente sob clima quente e umido. A analise de fitolitos do intervalo 2 (~5441 anos AP – idade interpolada a ~143 anos cal AP) sugeriu a presenca de uma vegetacao em mosaico provavelmente constituida por diferentes formacoes da restinga, sob influencia de clima quente e sazonal, com periodos de estresse hidrico. A diminuicao da densidade arborea, assinalada pelo indice D/P, e a formacao da vegetacao semelhante a atual, herbacea e com sinais de antropizacao, ocorreu nos ultimos ~200 anos (Intervalo 3), sob clima quente e umido. Os dados de fitolitos sao ineditos para a costa do Espirito Santo e mostram o potencial destes bioindicadores em estudos de reconstituicao paleoambiental. Normal 0 21 false false false PT-BR X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-fareast-language:EN-US;}

The study place is in the Barreirinhas region, Maranhão State, northeastern Brazil. A vegetation transect of 78 km was studied among four vegetation types: Restinga (coastal vegetation), Cerrado (woody savanna), Cerrad"o (dense woody savanna), and Forest, as well as three forested sites around Lagoa do Caçó, located approximately 10 km of the transect. Soil profiles in this transect were sampled for δ13C analysis, as well as buried charcoal fragments were used for 14C dating. The data interpretation indicated that approximately between 15,000 and ∽9000 14C yr B.P., arboreal vegetation prevailed in the whole transect, probably due to the presence of a humid climate. Approximately between ∽9000 and 4000–3000 14C yr B.P., there was the expansion of the savanna, probably related to the presence of drier climate. From ∽4000–3000 14C yr B.P. to the present, the results indicated an increase in the arboreal density in the area, due to the return to a more humid and probably similar climate to the present. The presence of buried charcoal fragments in several soil depths suggested the occurrence of palaeofires during the Holocene. The vegetation dynamic inferred in this study for northeastern Brazil is in agreement with the results obtained in areas of Amazon region, based on pollen analysis of lake sediments and carbon isotope analysis of soil organic matter (SOM), implying than similar climatic conditions have affected these areas during the late Pleistocene until the present.

This study presents paleoenvironmental data based on pollen, elemental and isotopic compositions of organic matter (TOC, N, d13C and d15N) and 14C dating of 170 cm lake sediment record. Samplings have been made in Lagoa Grande at Parque Estadual Turístico do Alto Ribeira - PETAR, Southern São Paulo State, Southeastern Brazil. The variations in relative frequencies (in percentage) of arboreal pollen along the core range between 40 and 80%. The d13C values ranged from -23‰ to -30‰ and C/N of ~10 to 15, indicating the contribution of terrestrial C3 plants and algae in the sediment organic matter. The d15N results presented values from 3 to 4.5‰, also suggesting a mixture of algae and terrestrial C3 plants. The 14C dating indicates modern age for the shallow horizons to ~1030 BP at the base of the core. A probable wetter climate in the period of ~370 BP to ~340 BP was inferred from the data set, which corresponds to a part of the period covered by the Little Ice Age (LIA).Este estudo apresenta dados paleoambientais baseados em análises de pólen, da composição elementar e isotópica da matéria orgânica (TOC, N, d13C e d15N) e datação 14C, de um testemunho sedimentar lacustre de 170 cm. A amostragem foi realizada na Lagoa Grande localizada no Parque Estadual Turistico do Alto Ribeira - PETAR, Vale do Ribeira, sul do estado de São Paulo, sudeste do Brasil. As variações nas frequências relativas de pólen arbóreo (em porcentagem) apresentaram-se entre 40 e 80% ao longo de todo o testemunho. Os valores de d13C variaram de -23‰ à -30‰, indicando a contribuição de plantas C3 (terrestres) e algas na matéria orgânica sedimentar. Os resultados de d15N apresentaram valores entre 3 e 4,5‰, também sugerindo uma mistura de algas e plantas C3. A datação 14C indica idade moderna para as camadas superficiais do testemunho e uma idade de até 1030 anos AP para a camada mais profunda do mesmo. Um provável clima mais úmido para o período de ~ 370 anos AP até ~ 340 anos AP foi inferido a partir dos resultados apresentados, correspondendo a uma parte do período do Little Ice Age (LIA - Pequena Idade do Gelo).

The aim of this research was to reconstruct vegetation changes (with climate inferences) that occurred during the Holocene in the Fernando de Noronha Island, Pernambuco State, northeastern Brazil. The research approach included the use of geochemical (mineralogy, elemental), carbon isotopes (δ13C, 14C) and pollen analyses in soil organic matter (SOM) and sediments collected in Lagoa da Viração and Manguezal do Sueste. The carbon isotopes data of SOM indicated that there was no significant vegetation changes during the last 7400 BP, suggesting that the climate was not the determinant factor for the vegetation dynamics. The pollen analysis of the sediment of a core collected in the Lagoa da Viração showed the absence of Quaternary material in the period between 720 BP and 90 BP. The mineralogical analysis of deeper layer showed the presence of diopside indicating this material was developed "in situ". Only in the shallow part of the core were found pollen of similar plant species of the modern vegetation. The geochemistry and isotope results, in association with the sediment type and pollen analyses of sediment samples of Manguezal do Sueste, indicated variations in the vegetation and in its location since the middle Holocene. Such variations can be associated with climatic events and sea level oscillations and also with anthropogenic events considering the last five hundred years._________________________________________________________________________________________ RESUMO: Esta pesquisa teve o objetivo de reconstruir trocas de vegetação (com referências climáticas) que ocorreram durante o Holoceno na ilha de Fernando de Noronha, Estado de Pernambuco, nordeste do Brasil. Para o desenvolvimento da pesquisa utilizou-se de análises geoquímicas (minerais, elementar), isótopos do carbono (δ13C, 14C) e análises polínicas em solos e sedimentos coletados na Lagoa da Viração e no manguezal do Sueste. Os isótopos do carbono dos solos indicaram que não houve trocas significativas de vegetação durante os últimos 7400 anos AP, sugerindo que o clima não foi um fator determinante para a dinâmica da vegetação. A análise polínica dos sedimentos da Lagoa da Viração mostrou ausência de elementos quaternários no período entre 720 AP e 90 AP. A análise mineralógica das camadas mais profundas mostrou a presença de diopsídeo, indicando que este material foi desenvolvido"in situ". Somente na parte superficial do testemunho foram encontrados palinomorfos de plantas similares à vegetação moderna. Os resultados geoquímicos e isotópicos, em associação com o tipo de sedimento e as análises polínicas das amostras de sedimento do Manguezal do Sueste, indicaram variações na vegetação e na sua localização desde o Holoceno médio. Tais variações podem estar associadas a eventos climáticos e oscilações do nível do mar e também a eventos antrópicos considerando os últimos quinhentos anos.

Analysis of biological proxies in lake sediment and geochemical analysis of soil profiles reveal natural vegetation dynamics, with climate inferences, since the late Pleistocene in a fragment of the pristine lowland Atlantic Forest of southeastern Brazil. Carbon isotopes from soil organic matter and 14C ages from the humin fraction indicate the dominance of C3 plants since ∼17,000 cal BP. Palynological analysis of a sediment core indicates the presence of Atlantic Forest vegetation since 7700 cal BP. Changes in the relative abundance of tree ferns and palms suggest the predominance of a humid period from ∼7000–4000 cal BP and establishment of the modern seasonal climate at ∼4000 cal BP. Data indicate maintenance of the regional forest coverage since the late Pleistocene, corroborating previous suggestions that this region was a forest refuge during less humid periods of the late Pleistocene and Holocene. Some plant taxa with currently divided distributions between Amazonia and the Atlantic Forest colonized the region since at least 7500 cal BP, indicating an earlier connection between Amazonia and Atlantic Forest.

A sediment core was studied to characterize the influences of Holocene sea-level variations in the Barra Seca River valley, in the Atlantic rainforest, Linhares, Espírito Santo, southeastern Brazil. Biological proxies (pollen, spores, and sponge spicules), 14C dating, granulometry, δ13C, δ15N, C/N and major chemical elements revealed the establishment and the evolution of a paleo-estuary during the interval from ∼7700–585 cal BP. During the interval ∼7700–7000 cal BP, the study site was occupied by a bay-head delta, the inner portion of the paleo-estuary, presenting the most dense mangrove coverage of the entire record. In the interval ∼7000–3200 cal BP, the site was occupied by the central basin, possibly a consequence of the landward migration of the paleo-estuary. This interval presents reduced mangrove coverage, probably due to the permanent flooding of the valley. From ∼3200 cal BP, the marine influence at the site decreased probably as result of the seaward migration of the coast line. From ∼600 cal BP, the modern floodplain and freshwater lake were established. This interpretation is in agreement with the sea-level curves for the southeastern Brazilian coast, except for the fact that evidence of sea levels lower than the present at ∼4000 and ∼2500 cal BP as suggested by some authors were not found.