Pliocene seasonality across the North Atlantic inferred from cheilostome bryozoans

Previous studies have shown an inverse correlation between zooid size in cheilostome bryozoans and ambient water temperature. This relationship underlies the MART technique which uses intracolonial variation in zooid size to predict mean annual range in temperature experienced by bryozoan colonies during their life. Here we apply the MART technique to study Early and Mid Pliocene bryozoans from Central America (Panama, Costa Rica), the USA (Florida, South Carolina, North Carolina, Virginia) and the UK (Suffolk) to reconstruct palaeoseasonality across a range of latitudes for the North Atlantic during the Pliocene Epoch. Compared to the present-day, our analyses suggest greater seasonality (ca 4.5 degrees C) in the southern Caribbean at the time of Cayo Agua Formation deposition (ca 4.25 Ma), in keeping with inferred upwelling prior to the closure of the isthmian barrier at 2.7 Ma. Bryozoans also indicate seasonal upwelling on the Gulf Coast of Florida in a similar manner to the present-day. Because upwelling can be highly localised and prone to spatial and temporal variation in the Gulf of Mexico today, it contributes little to a broad understanding of Pliocene North Atlantic waters. However, MART estimates for the coastal plain region indicate a general reduction in the annual range in temperature relative to the present, suggesting that the colder surface waters that today reach south to Cape Hatteras had less influence in Early to Mid Pliocene times. These results, along with evidence from other proxies, strongly support reduced seasonality and warmer conditions along the eastern seaboard of the USA in the Early to Mid Pliocene. Finally, the MART estimates amongst Coralline Crag localities provide evidence for an increased annual range in temperature in the southern North Sea than at present. Our study shows that bryozoan MART estimates provide a powerful, independent proxy for palaeoseasonality and is the first to demonstrate that the MART technique can be applied to infer palaeoclimates across a wide range of latitudes focusing on a variety of geological formations and geographical regions. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.

Reproductive biology of six Brazilian Myrtaceae: is there a syndrome associated with buzz-pollination?

The floral phenology and reproductive biology of six sympatric arboreal Myrtaceae species were studied in the coastal plain forest (Ubatuba, Brazil, 44 degrees 48`W 23 degrees 22`S), from September 1999 to April 2002. Flowering started in the transition from the driest to the most humid season (Sep/Oct) and lasted until March. The sequence with which the species flowered each year was consistently the same. However, the timing of flowering onset, peak, end, and overlap differed from one year to another. Myrtaceae species were classified as xenogamic according to the pollen:ovule ratios, but two of them seem to present some degree of self-compatibility. Flowers of all species opened at sunrise and lasted for I day. Bombus morio (Apidae: Bombini) was the most common visitor followed by Melipona rufiventris (Apidae: Meliponini). Buzz pollination in Myrtaceae was common at the study area and seems to be related to bees` behaviour and to some aspects of flowers` morphology.

Hybridization and introgression across different ploidy levels in the Neotropical orchids Epidendrum fulgens and E-puniceoluteum (Orchidaceae)

The hypothesis of gene flow between species with large differences in chromosome numbers has rarely been tested in the wild, mainly because species of different ploidy are commonly assumed to be reproductively isolated from each other because of instantaneous and strong postzygotic barriers. In this study, a broad-scale survey of molecular variation was carried out between two orchid species with different ploidy levels: Epidendrum fulgens (2n = 2x = 24 chromosomes) and Epidendrum puniceoluteum (2n = 4x = 52 chromosomes). To test the strength of their reproductive barriers, we investigated the distribution of genetic variation in sympatric and allopatric populations of these two species and conducted crossing experiments. Nuclear and plastid microsatellite loci were used to genotype 463 individuals from eight populations across the geographical range of both species along the Brazilian coastal plain. All six sympatric populations analysed presented hybrid zones, indicating that hybridization between E. fulgens and E. puniceoluteum is a common phenomenon. Bayesian assignment analysis detected the presence of F(1) and F(2) individuals and also signs of introgression, demonstrating a high potential for interspecific gene flow. Introgression occurs preferentially from E. fulgens to E. puniceoluteum. Pure parental individuals of both species display strong genotype-habitat associations, indicating that environment-dependent selection could be acting in all hybrid zones. This study suggests that hybridization and introgression are evolutionary processes playing a role in the diversification of Epidendrum and indicates the importance of investigations of hybrid zones in understanding reproductive barriers and speciation processes in Neotropical orchid species.

STRUCTURE OF THE SHRUB-ARBOREAL COMPONENT OF AN ATLANTIC FOREST FRAGMENT ON A HILLOCK IN THE CENTRAL LOWLAND OF RIO DE JANEIRO, BRAZIL

The present study describes and evaluates the horizontal and vertical structures of a lowland forest fragment on a hillock in the municipality of Silva Jardim, Rio de Janeiro State, Brazil (22 degrees 31`56 `` S and 42 degrees 20`46 `` W). Twenty plots (10x2m) totaling 0.5ha were laid out following the slope grade using DBH >= 5cm as the inclusion criterion. A total of 734 individuals were encountered, yielding a total density of 1468 ind./ha and a total basal area of 10783m(2). The richness values (129 species/41 families), Shannon-Wiener diversity (4.22) and equitability (0.87) indices indicated an accentuated floristic heterogeneity and low ecological dominance. Lauraceae, Myrtaceae, Fabaceae and Euphorbiaceae showed the greatest species richness, corroborating other studies that indicated these species as the most representative of Atlantic Forest areas in southeastern Brazil. The species with the greatest importance values (VI) were Aparisthmium cordatum, Guapira opposita, Lacistema pubescens, Xylopia sericea, Tapirira guianensis and Piptocarpha macropoda. The high diversity observed was influenced by earlier anthropogenic actions and by the current successional stage. The forest fragment studied demonstrated closer floristic similarity to areas inventoried in a close-by biological reserve than to fragments dispersed throughout the coastal plain. Similarities in soil type, degree of soil saturation and use-history of forest resources all support these relationships. The fragmented physiognomy of the central lowland in this region and the use-history of the landscape make these small remnant forest areas important in terms of establishing strategies for landscape restoration and species conservation.

Terraços da margem leste da Laguna dos Patos, Litoral Médio do Rio Grande do Sul: estratigrafia e evolução holocênica

O presente trabalho discute os terraços lagunares da margem leste da Laguna dos Patos, localizados próximo à cidade de Mostardas. Através desse estudo é apresentado um novo modelo evolutivo para os últimos 5.000 anos no Litoral Médio do Rio Grande do Sul. Novas ferramentas foram utilizadas pela primeira vez no estudo da planície costeira do Rio Grande do Sul. Com respeito a aquisição dos dados de subsuperfície foi utilizado com êxito um GPR (Ground Penetretion Radar). Na análise e interpretação dos dados foi feita uma tentativa de aplicação da estratigrafia de seqüências. Através do uso de um scanner foram elaborados perfis dos testemunhos de sondagem, identificando aspectos distintos na composição e porosidade de diferentes litologias. Outras ferramentas utilizadas constam de sensoriamento remoto, nivelamento altimétrico e batimétrico, vibracore e datação radiométrica. Dessa forma, foram definidas três feições de terraceamento lagunar de idade holocênica na área de estudo, cada uma relacionada a um nível lagunar distinto. Através dos dados obtidos em subsuperfície foi possível traçar um esboço cronoestratigráfico, bem como uma curva de variação relativa do nível lagunar para a região. Também, como resultado dos dados geológicos de superfície, associados a novas interpretações baseadas em fotografias aéreas e imagens de satélite, foi elaborado um mapa geológico atualizado.

Monitoramento por dgps e análise dos processos erosivos da linha de costa na praia de Pirangi do Norte - Parnamirim / RN

Through out the course of a steady increase in search and recovery of space in the coastal zone, there is also an expanding concern about the erosion processes of this area. The main problem in coastal areas is that urbanization occurs in a disorderly fashion and unsustainable, further aggravating the problems of coastal dynamics. The study area of this work is located on the southern coast of Pirangi do Norte beach to about 20km south of Natal, capital of Rio Grande do Norte in the Parnamirim City. This area has the length of approximately 1km, divided into three sections (Western, Central and Eastern) with a morphology consisting of a tableland at the top, sea cliffs in the West and Central parts and sand dunes in the Eastern section, both vegetated, and a coastal plain on the inferior part associated with the presence of beach rocks. This study aimed to analyze the erosion processes operating in the excerpt of Pirangi do Norte beach and assess the feasibility of their monitoring making use of DGPS (Global Positioning System Differential mode). During the work it was carried out a physical description of the area through photo-interpretation and site survey after measurement of the shoreline in the period between November 2004 and November 2009 and beach profiles between August 2005 and July 2006. The analysis of the results of the annual surveys showed the occurrence of variations of the shoreline along the stretch traveled. Sites are identified in advancement coast from the sea and it was verified in loco the presence of erosion with deposition of materials on the lower part of the coastal bluff, the former position of the shoreline, showing a false notion of advancing it. This leads to the conclusion that the data collected in a survey of the shoreline should always be accompanied by photographic records of the local area and with the highest rate of erosion, thus avoiding the mistake of treating the deposit materials as evidence of progress coast. At the end of the study, after a review of various works to mitigate the erosion in the coastal zone, it is recommended to the area of study the adoption of an artificial feeding of the beach, aiming the minimization of the erosive effects of the tides. Moreover, it is suggested that even the continuity of monitoring, maintenance of existing vegetation and control of the occupation on the edge of sea cliffs

Caracterização de processos morfodinâmicos e hidrodinâmicos do cinturão lacustre meridional da Reserva Biológica do Lago Pirituba, Amapá

The Amapá State has an important natural lake system, known as The Amapá Lakes Region . Most of these lakes are on the southern part of Amapá s coastal plain, which has 300 km of extension and it s composed by holocenic sediments deposited at the northern part of Amazon River to the Orange Cape located on the northern part of Amapá state. This region is under influence of the Amazon River discharge which is the largest liquid discharge of about 209.000 m³/s and biggest sediment budget discharged on the ocean in the order 6.108 ton per day. The climate is influenced by the Intertropical Convergence Zone and El Niño Southern Oscillation which act mainly under precipitation, nebulosity, local rivers and tidal hidrology. In this region lake belts are Ocidental, Oriental and Meridional Lake Belts. The last one is formed by the by the lakes Comprido de Cima, Botos, Bacia, Lodão, Ventos, Mutuco and Comprido de Baixo. These lakes are the closest to the Araguari River and are characterized by pelitic sedimentation associated with fluvial and estuarine flood plains under influence of tides. The lakes are interconnected, suffer influence of flood pulses from the Tartarugal, Tartarugalzinho and Araguari rivers and the hydrodynamic and morphodynamic know edge is poor. Volume and area reduction, natural eutrophication, anthophic influence, hidrodynamic alterations, morphological changes and are factors which can contribute to the closing of such lakes on the Meridional Lake Belt. This belt is inside the boundaries of the Biological Reserve of Piratuba Lake, created in 1980 for integral protection. Due to the fragility of the environment together with the poor knowledge of the system and with the study area relevancy it is necessary to know the hydrodynamic and geoenvironmental processes. This work aims the characterization of morphodynamic and hydrodynamic processes in order to understand the geoambiental context of the Meridional Lake Belt, from the Comprido de Baixo Lake to the dos Ventos Lake, including the Tabaco Igarape. Methodology was based on the hydrodynamic data acquisition: liquid discharge (acoustic method), tides, bathymetry and the interpretation of multitemporal remote sensing images, integrated in a Geographic Information System (GIS). By this method charts of the medium liquid discharges of Lake Mutuco and Tabacco Igarape the maximum velocity of flow were estimated in: 1.1 m/s, 1.6 m/s and 1.6 m/s (rainy season) and 0.6 m/s, 0.6 m/s and 0.7 m/s (dry period), the maximum flow in: 289 m³/s, 297 m³/s and 379 m³/s (rainy season) and 41 m³/s , 79 m³/s and 105 m³/s (dry period), respectively. From the interpretation of multitemporal satellite images, maps were developed together with the analysis of the lakes and Tobaco Igarape evolution from 1972 to 2008, and were classified according to the degree of balance in the area: stable areas, eutrophic areas, areas of gain, and eroded areas. Troughout analysis of the balance of areas, it was possible to quantify the volume of lake areas occupied by aquatic macrophytes. The study sought to understand the hydrodynamic and morphodynamic processes occurring in the region, contributing to the elucidation of the processes which cause and/or favor geoenvironmental changes in the region; all such information is fundamental to making the management of the area and further definition of parameters for environmental monitoring and contributing to the development of the management plan of the Biological Reserve of Lake Piratuba. The work activities is a part of the Project "Integration of Geological, geophysical and geochemical data to Paleogeographic rebuilding of Amazon Coast, from the Neogene to the Recent

Candida bromeliacearum sp nov and Candida ubatubensis sp nov., two yeast species isolated from the water tanks of Canistropsis seidelii (Bromeliaceae)

Strains belonging to two novel yeast species, Candida bromeliacearum and Candida ubatubensis, were isolated from the bromeliad tank of Canistropsis seidelii (Bromeliaceae) in a sandy coastal plain (restinga) ecosystem site in an Atlantic rainforest of south-eastern Brazil. These species were genetically distinct from all other currently accepted ascomycetous yeasts, based on sequence divergence in the D1/D2 domains of the large-subunit rDNA and in the small-subunit rDNA. The species occupy basal positions in the Metschnikowiaceae clacle. The type strains are Candida bromeliacearum UNESP 00-103(T) (=CBS 10002(T) = NRRL Y-27811(T)) and Candida ubatubensis UNESP 01-247R(T) (=CBS 10003(T) = NRRL Y-27812(T)).

Reproductive phenology of Euterpe edulis (Arecaceae) along a gradient in the Atlantic rainforest of Brazil

The palm Euterpe edulis Mart. is one of the dominant tree species in the Atlantic rainforest and considered a key resource for many frugivorous birds. We compared the reproductive phenology of E. edulis in three types of Atlantic rainforest (two lowland forests, restinga and coastal-plain, and a premontane forest) on Cardoso Island (Cananeia, São Paulo, Brazil), aiming to answer the following questions: (i) whether the reproduction of E. edulis is annual and seasonal across the years in the three forest types studied; (ii) what are the environmental factors influencing the reproductive phenology of E. edulis; and (iii) how does the timing of fruiting and fruit production of E. edulis vary among the three forest types? We evaluated the presence of flowers and fruits (immature, unripe and ripe) from August 2001 to July 2004 in 150 individuals (50 per forest), and estimated the number of infructescences with ripe fruits and the production of fruits and seeds by collecting them on the forest floor in the three forest types. Flowering and fruiting of E. edulis were annual and significantly seasonal in the three forest types, with a high synchrony of flowering and medium to low synchrony of fruiting. Flowering peaked in November and December, and immature and unripe fruits peaked in January and March, all during the rainy season. Immature and unripe fruit phases were correlated with the daylength, precipitation and temperature, important factors for fruits development. Ripe fruits peaked in April and May, in the less rainy season, with significant differences in the mean dates among forests. The number of infructescences with ripe fruits and the biomass of fruits and seeds collected on the ground also differed significantly among the forest types, being greater in the restinga and coastal plain forests, respectively. Differences in productivity were related to palm density in each area and the soil fertility. The complementary fruiting pattern of E. edulis in the forests studied may affect the distribution and abundance of certain frugivorous bird species that feed on their fruits.

Composição florística e estrutura fitossociológica de dois fragmentos de floresta de restinga no Município de Bertioga, SP, Brasil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Florística e fitossociologia em parcelas permanentes da Mata Atlântica do sudeste do Brasil ao longo de um gradiente altitudinal

This paper summarizes floristic and phytossociology data of 11, out of 14 plots of 1 ha, allocated along an altitudinal gradient in the Serra do Mar, Silo Paulo, Brazil. The study was conducted at Serra do Mar State Park and the plots start at the sea level (10 m - plot of Restinga Forest that occurs at Praia da Fazenda, Picinguaba, municipality of Ubatuba) up to 1100 m above sea level (the Montane Ombrophilous Dense occurs alongside the Itamambuca Trail, municipality of Silo Luis do Paraitinga). The Restinga Forest occurs in Pleistocenic Coastal Plain where the soil is classified as a sandy Quartzipsamment (Quartzenic Neosol), while along the slopes of the Serra do Mar, the Ombrophylus Dense Forest grows on the top of a pre-Cambrian crystalline basement with granitic rocks, where the soil is a sandy-loam Dystrophic Inceptisol (Cambisol/Latosol). In all 14 plots soils are acidic (pH 3 - 4), chemically poor, with high dilution of nutrients and high saturation of aluminum. In the Restinga and at the foot of the slope the climate is Tropical/Subtropical Humid (Af/Cfa), with no dry season, an average annual rainfall over 2,200 mm and an average annual temperature of 22 degrees C. Towards the top of the Serra do Mar there is a gradual cooling along the slope, but there is no reduction in rainfall, so at 1,100 m above sea level the climate is classified as Humid Subtropical (Cfa/Cfb), with no dry season and an average annual temperature of 17 degrees C. It is important to remark that, almost daily, from 400 m above sea level up to the top of slopes the mountains are covered by a dense fog. In the 14 plots 21,733 individuals with DBH >= 4.8 cm, including trees, palms and ferns, were marked, measured and sampled. The average number of individuals sampled in each plot was 1264 ind.ha(-1)(+/- 218 SE 95%). Within the parameters considered trees prevailed (71% in the Montane ODF to 90% in the Restinga Forest), followed by palms (10% in the RF and 25% in the Montane Ombrophilous Dense Forest/ODF) and ferns (0% % in the RF and 4% in the Montane ODF). Regarding these proportions the Exploited Lowlands ODF differs from the others with only 1.8% of palm trees and striking 10% of ferns. The forest canopy is irregular with heights ranging from 7 to 9 m, rarely emergent trees reach 18 m, and due to this irregularity of the canopy the amount of light that gets through sets conditions for the development of hundreds of epiphytic species. Aside from Montana ODF, where the number of dead trees was more than 5% of individuals sampled, in the other phytophysiognomies this value was below 2.5%. In the 11 plots where the floristic study was conducted we found 562 species in 195 genera and 68 families. Only seven species - Euterpe edulis Mart. (Arecaceae), Calyptranthes lucida Mart. ex DC. and Marlierea tomentosa Cambess (both Myrtaceae), Guapira opposita (Veil.) Reitz (Nyctaginaceae), Cupania oblongifolia Mart. (Sapindaceae), Cecropia glaziovii Snethl. and Coussapoa microcarpa (Schott) Rizzini (both Urticaceae) - occurred from Restinga to Montane ODF, while 12 other species did not occur only in the Restinga Forest. Families with the greatest number of species are Myrtaceae (133 spp), Fabaceae (47 spp), Rubiaceae (49) and Lauraceae (49) throughout the gradient and Monimiaceae (21) specifically in portions Montane ODF. Only in the F plot, where logging has occurred between 1950 and 1985, the abundance of palm trees has been replaced by Cyatheaceae. The study shows a peak of diversity and richness, Shannon-Weiner index (H') ranging from 3.96 to 4.48 nats.ind(-1), in the intermediate altitudes (300 to 400 m) along the slope. Several explanations for this result are raised here, including the fact that these elevations are within the limits expansions and retractions of the different phytophysiognomies of the Atlantic ODF due to climate fluctuations during the Pleistocene. The results presented in this paper demonstrate the extraordinary richness of tree species of the Atlantic Rainforest from the northeastern coast of the State of São Paulo, reinforcing the importance of its conservation throughout the altitudinal gradient. The richness of this forest justifies a long term commitment to study its dynamics and functioning through permanent plots, and monitor the impacts of climate change in this vegetation.

Estudo comparativo da fenologia de nove espécies arbóreas em três tipos de floresta atlântica no sudeste do Brasil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)