Modern processes of palynomorph deposition at lakes of the northern region of the Rio de Janeiro State, Brazil

Palynological analysis of pollen, Pteridophyta spores and algae deposited in the superficial sediments at Lagoa de Cima and Lagoa do Campelo Lakes, located in the north of Rio de Janeiro state, was used to determine the spatial variation of the palynomorphs deposition. A total of 67 pollen types were identified at Lagoa de Cima, with an expressive contribution of regional arboreous taxa, hydrophytes and ruderal plants of the pastureland. The depositional pattern of palynomorphs depends on the fluvial leakage, the proximity of the local sedimentation to the inlet of the Imbé and Urubu Rivers and the bathymetry of lake bottom. The highest concentrations of palynomorphs were observed in the decentralized and less deeper area, without the interference of the northeastern wind. At Lagoa do Campelo, a total of 58 pollen types were identified, among which the majority of the pollen grains came from hydrophytes, with the highest concentrations found along the northeastern shore. The southeastern shore showed high percentages of pollen and spores with degraded exine and mechanical damage, due to the transport through the lakeby the currents caused by the wind, confirmed by the depositional trend of damaged palinomorphs along the same direction as the prevailing winds.

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Spatial distribution of pollen grains and spores in surface sediments of Guanabara Bay, Rio de Janeiro, Brazil

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652012005000049 ◽

2012 ◽

Vol 84 (3) ◽

pp. 627-644 ◽

Cited By ~ 7

Author(s):

Cintia F. Barreto ◽

Claudia G. Vilela ◽

José A. Baptista-Neto ◽

Ortrud M. Barth

Keyword(s):

Rio De Janeiro ◽

Surface Sediments ◽

Pollen Grains ◽

Source Area ◽

Guanabara Bay ◽

Differential Distribution ◽

Hydrographic Basin ◽

River Transport ◽

Pollen Types ◽

Janeiro State

Aiming to investigate the deposition of pollen grains and spores in Guanabara Bay, Rio de Janeiro State, 61 surface sediment samples were analyzed. The results showed that the current deposition of palynomorphs in surface sediments of Guanabara Bay represents the regional vegetation of this hydrographic basin. The differential distribution of palynomorphs followed a pattern influenced by bathymetry, tidal currents speed, discharge of numerous rivers, and by human activity. The dominance of representatives of Field Vegetation reflects the changes of the original flora caused by intense human activities in the region. The continued presence and richness of pollen types of rain forest in the samples indicates that their source area might be the vegetation from riparian border of rivers in the western sector of the Bay, where the mangrove vegetation is being preserved. The large amount of damaged palynomorphs may be related to abrasion that occurs during river transport, indicating removal or reworking from their areas of origin.

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Mercury and organic carbon distribution in six lakes from the North of Rio de Janeiro State

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132004000100019 ◽

2004 ◽

Vol 47 (1) ◽

pp. 139-145 ◽

Cited By ~ 11

Author(s):

Wanderson Primo de Sousa ◽

Carlos Eduardo Veiga de Carvalho ◽

Claudia Calasans Veiga de Carvalho ◽

Marina Satika Suzuki

Keyword(s):

Organic Carbon ◽

Rio De Janeiro ◽

Gold Mining ◽

Mercury Contamination ◽

Carbon Distribution ◽

Mining Areas ◽

The Past ◽

The North ◽

Superficial Sediments ◽

Janeiro State

The objectives of the study was to evaluate the mercury contamination in sediments of six lagoons located in the north region of Rio de Janeiro State, trying to relate the Hg concentrations with factors that could influence it's mobility, such as organic carbon. The highest values observed in the superficial sediments in lakes like Campelo (349,6 µg.kg -1) suggested a recent Hg input into the system. The correlation Hg/Organic carbon was positive for most areas, indicating that the organic carbon was a significant parameter for Hg retention in this region. The obtained results suggested that the mercury used as fungicide in agriculture lands and in gold mining areas in the past were probably responsible for the contamination of this environment.

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Spatial distribution of palynomorphs in the surface sediments of the Lagoa do Campelo lake, North region of Rio de Janeiro State, Brazil

Acta Botanica Brasilica ◽

10.1590/s0102-33062005000400009 ◽

2005 ◽

Vol 19 (4) ◽

pp. 741-752 ◽

Cited By ~ 7

Author(s):

Cynthia Fernandes Pinto da Luz ◽

Ortrud Monika Barth ◽

Cleverson Guisan Silva

Keyword(s):

Spatial Distribution ◽

Surface Sediments ◽

Mechanical Damage ◽

Pollen Grains ◽

Pollen Grain ◽

New Information ◽

Lake Bottom ◽

Wind Driven Currents ◽

Trees And Shrubs ◽

Janeiro State

Four samples of the surface sediments of the Lagoa do Campelo lake bottom were collected in a transect of 500 m by 500 m from edge to edge, in a northeast/southwest direction, the dominant wind direction in the region. The analysis of pollen grains, fern spores and algae were used to evaluate their spatial deposition and level of deterioration. In total, 58 types of pollen grains were identified, mainly from herbs as Cyperaceae, Poaceae and Typhaceae. Pollen grains occurred in all the analyzed sediments. The area of highest concentration was the northeast side of the lake. The southwest side showed the highest pollen grain and fern spore degradation and mechanical damage, probably as they were carried across the lake by wind-driven currents, confirming the depositional tendency of damaged palynomorphs in the same direction as the dominant wind. Among the pollen of trees and shrubs, Alchornea, Arecaceae, Cecropia, Celtis, Clethra and Myrtaceae were dominant at more than 1,000 pollen grains per gram of sediment. The quantity of fern spores was practically constant in all samples (± 10% of the total of palynomorphs). The algae Pediastrum tetras (Ehrenberg) Ralfs and Mougeotia occurred in all samples, but Spirogyra only in three of them. The results obtained gave new information about the richness, concentration and distribution of palynomorphs in the lake, representing the local and regional vegetation.

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Photosynthetic capacity of 'Niagara Rosada' grapes grown under transparent plastic covering

Ciência Rural ◽

10.1590/0103-8478cr20150400 ◽

2016 ◽

Vol 46 (6) ◽

pp. 950-956 ◽

Cited By ~ 2

Author(s):

Bruna Corrêa da Silva de Deus ◽

Fábio Afonso Mazzei Moura de Assis Figueiredo ◽

Luciana Venturotti Braun de Almeida ◽

Tiago Massi Ferraz ◽

Amanda Oliveira Martins ◽

...

Keyword(s):

Rio De Janeiro ◽

Photosynthetic Capacity ◽

Block Design ◽

Northern Region ◽

Maximum Temperature ◽

Transparent Plastic ◽

Tropical Regions ◽

The North ◽

Janeiro State ◽

Niagara Rosada

ABSTRACT: New techniques in tropical regions such as use of transparent plastic covering (TPC), have been employed in grapes to avoid the wetting leaves and fruits, which can reduce the occurrence of fungal diseases, reduce the use of sprays, and reduce damage caused by hail and high winds. TPC may significantly affect the photosynthetic rates of grapevines cultivated in tropical regions, and thus have strong effects on plant productivity and improve fruit quality. However, in the North of Rio de Janeiro region there are lacks of studies related to TPC effects on photosynthetic capacity. The objective of this study was to evaluate the photosynthetic capacity in 'Niagara Rosada' vines grown under TPC and without transparent plastic covering (WTPC). The experiment was conducted between April and June 2013, on Tabuinha farm, located in the 3rd district of São Fidélis, Rio de Janeiro State, Brazil. A completely randomized block design was used with two treatments (TPC and WTPC) and twelve replications. Evaluations consisted of climatological variables, gas exchange and maximum quantum efficiency of open photosystem II centers-quantum yield (Fv/Fm) It was possible to observe that under TPC maximum temperature increase of 2.3°C, relative humidity reduced 1.5%, vapor pressure deficit increase 0.4kPa, and light intensity reduced 47.7%. These changes did not cause photochemical damage to the leaves. The TPC promoted higher net photosynthetic rate at 800h, which was associated with higher stomatal conductance. Thus, the TPC used in the northern region of Rio de Janeiro State did not impair the photosynthetic capacity of 'Niagara Rosada' vines.

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Geo-enviromental diagnoses of the são francisco de itabapoana city in the north of Rio de Janeiro state

Brazilian Journal of Development ◽

10.34117/bjdv6n5-217 ◽

2020 ◽

Vol 6 (5) ◽

pp. 26764-26775

Author(s):

Graziele Arantes Reis ◽

Iago Matheus Lopes Macêdo ◽

Rodson de Abreu Marques

Keyword(s):

Rio De Janeiro ◽

The North ◽

Janeiro State

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Glomalin in soil aggregates under different forest and pasture systems in the North of Rio de Janeiro state, Brazil

Environmental and Sustainability Indicators ◽

10.1016/j.indic.2020.100088 ◽

2020 ◽

Vol 8 ◽

pp. 100088

Author(s):

Alessandro Santos ◽

Cristiane Figueira da Silva ◽

Emanuela Forestieri Gama-Rodrigues ◽

Antonio Carlos Gama-Rodrigues ◽

Marcus Sales ◽

...

Keyword(s):

Rio De Janeiro ◽

Soil Aggregates ◽

The North ◽

Janeiro State

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Thermal characterisation of red clay from the Northern Region of Rio de Janeiro State, Brazil using an open photoacoustic cell, in relation to structural changes on firing

Applied Clay Science ◽

10.1016/j.clay.2008.01.010 ◽

2008 ◽

Vol 42 (1-2) ◽

pp. 168-174 ◽

Cited By ~ 19

Author(s):

L. Mota ◽

R. Toledo ◽

F.A.L. Machado ◽

J.N.F. Holanda ◽

H. Vargas ◽

...

Keyword(s):

Rio De Janeiro ◽

Structural Changes ◽

Northern Region ◽

Photoacoustic Cell ◽

Red Clay ◽

Open Photoacoustic Cell ◽

Janeiro State

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ARRANJO POPULACIONAL PARA A VARIEDADE UENF-14 DE MILHO PIPOCA

Revista Brasileira de Milho e Sorgo ◽

10.18512/1980-6477/rbms.v16n3p401-413 ◽

2017 ◽

Vol 16 (3) ◽

pp. 401

Author(s):

CÁSSIO VITORAZZI ◽

ANTONIO TEIXEIRA AMARAL JÚNIOR ◽

LILIAM SILVIA CANDIDO ◽

ISMAEL LOURENÇO DE JESUS FREITAS ◽

THIAGO RODRIGUES DA CONCEIÇÃO SILVA

Keyword(s):

Zea Mays ◽

Grain Yield ◽

Rio De Janeiro ◽

Zea Mays L ◽

Block Design ◽

Grain Production ◽

Maize Population ◽

The North ◽

Randomized Complete Block Design ◽

Janeiro State

RESUMO - A adequação do arranjo populacional está entre as técnicas que podem maximizar a produtividade da cultura do milho. Daí a importância das pesquisas que buscam estudar o desempenho de cultivares de milho e milhos especiais, a fim de determinar o arranjo de plantas ideal. O objetivo deste trabalho foi avaliar o desempenho da variedade UENF-14, de milho pipoca, cultivada em diferentes arranjos populacionais, na safra e safrinha, para otimizar a recomendação fitotécnica para os produtores rurais do Norte Fluminense. Foram instalados dois experimentos em Campos dos Goytacazes-RJ. Um na safrinha 2011 utilizando a variedade UENF-14 e o híbrido experimental P2 x P9, e o outro na safra 2011-2012, com a variedade UENF-14 e o híbrido comercial IAC-112. O delineamento experimental, nos dois experimentos, foi o de blocos casualizados arranjados em parcelas subsubdivididas, em que as parcelas foram compostas pelos genótipos, as subparcelas constituídas pelos espaçamentos entre linhas de semeadura (0,45, 0,60 e 0,90 m) e as subsubparcelas compostas pelas densidades de plantas (60.000, 75.000 e 90.000 plantas ha-1). A UENF-14 apresentou desempenho superior aos híbridos, demonstrando seu potencial para cultivo na região Norte Fluminense. Houve aumento do rendimento de grãos com a diminuição do espaçamento entre linhas de plantio. Para a variedade UENF-14, a redução do espaçamento entre linhas de plantio foi vantajosa para a produção de grãos, independentemente da época de semeadura.Palavras-chave: Zea mays L., densidade de semeadura, espaçamento entre linhas, épocas de semeadura. POPULATION ARRANGEMENT FOR THE VARIETY OF POPCORN UENF-14 ABSTRACT - The adequacy of the maize population arrangement is among the most important techniques for obtaining higher yields. Therefore, many researchers have been conducting an attempt to study the performance of corn and specialty corn. The objective was to evaluate the performance of the popcorn variety UENF-14 in different population arrangements, in the harvest season and off-season. Two experiments were carried out in Campos dos Goytacazes, North of Rio de Janeiro State, Brazil, in the off-season 2011, using the UENF-14 variety and the experimental hybrid P2 x P9, and in the season 2011-2012 using UENF-14 and the commercial hybrid IAC-112. The treatments were arranged in randomized complete block design with split plots, in which plots were composed by popcorn genotypes, the subplots consisting of three spacings between sowing lines (0.45, 0.60 and 0.90 m) and the subsubplots composed of three plants per hectare densities (60,000, 75,000 and 90,000 plants.ha-1). The variety UENF-14 presented higher performance than the hybrids, demonstrating its potential for recommendation to the North of Rio de Janeiro State. There was an increase of grain yield by reducing the spacing between the plants rows. The cultivation of the variety UENF-14 reducing the spacing between rows was advantageous for grain production, regardless of planting date.Keywords: Zea mays L., densities of plants, spacing between rows, sowing times.

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