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The vegetation history and climate in southeastern Brazil, as well as the oceanic dynamics of the tropical Atlantic Ocean offshore, were reconstructed for the last 7.4 cal ka BP. This reconstruction was based on pollen, fern spores and dinoflagellate cysts identified in a marine core (CF10–04B). It was possible to verify the presence of an ombrophilous forest from 7.4 cal ka BP. Near the base of the PI zone low concentrations of pollen and fern spores are recorded, along with low frequencies of forest taxa and fern spores and an increase in pollen types of open vegetation, suggesting less humid climatic conditions than currently observed in the coastal regions of Southeastern Brazil. The assemblages of dinoflagellate cysts suggest a neritic zone with warm upper column temperature, high salinity and oligotrophic environment (evidenced by the presence of O. centrocarpum , Spiniferites spp. and L. machaerophorum). An increase in Tropical Waters (TW) and the approximation of the Brazilian Current (BC) in the middle shelf of southeastern Brazil in the mid-Holocene probably influenced the low accumulation of cysts, pollen grains, fern spores, and their associations. It is still possible to verify that at approximately 4.6 cal ka BP, an increase in the rainfall in the southeastern Brazilian region was probably the fundamental factor for the expansion of vegetation, mainly based on the considerable increases in hygrophytic and aquatic plants. The marked increase in the accumulation of dinoflagellate cysts, with the dominance of autotroph taxa (mainly O. centrocarpum , followed by Spiniferites spp), evidences the warmer waters of the BC and more intense surface upwelling of the South Atlantic Central Water (SACW). [ABSTRACT FROM AUTHOR]

Integration of late Quaternary continental and marine proxies allows improved reconstruction of palaeoenvironment and palaeoclimates models for the south-eastern coast of Brazil. In this paper, we analyse pollen, fern spores, and dinoflagellate cysts in a marine sediment core (GL74) over the last ∼109 kyr. Results showed that, between 109 and 89.5 kyr, low sea levels promoted the expansion of herbaceous taxa across open areas while climatic conditions were relatively warm and humid, as indicated by the high frequency of Atlantic rainforest Ombrophilous forest pollen types and abundant of fern spores. Between ∼79–49 kyr, higher concentrations of palynomorphs were recorded, which were likely related to the low relative sea level during the last glacial period. During this interval, there was a decrease in tree pollen grains and an increase in shrub and herbaceous pollen grains, indicating cold and relatively dry weather conditions. In the Holocene period, the low deposition of palynomorphs may have been influenced by the gradual submergence of the central part of the Brazilian coast. This process was associated with warm and humid climatic conditions, as suggested by the expansion of rainforests and the presence of hygrophyte/aquatic taxa and fern spores, as well as the retraction of grassland pollen types. Dinocyst assemblages suggest that nutrient-rich waters and/or the presence of upwelling cells were dominant between ∼109–88 kyr, but gradually reduced between 88 and 65 kyr (and/or ∼ 88–20 kyr) under the influence of subtropical fronts. The study culminated in the dominance of unproductive warm water in the upper column between 65 and 0.5 kyr. • Correlation of continental and marine proxies in south-eastern Brazil during the late Quaternary Late • Quaternary dynamics of the South Atlantic Ocean based on dinocysts • Reconstruction of palaeovegetation and palaeoclimate for the last ∼109 kyr along the southeast coast of Brazil [ABSTRACT FROM AUTHOR]

Here palynological assemblages are presented from channel surface sediment samples from the Caceribu, Guaraí and Guapimirim-Macacú rivers located in an important area of the Brazilian coast (Guanabara Bay, State of Rio de Janeiro), in order to provide information relevant for the interpretation of palaeoecological records. The data indicate the predominance of pollen types from the Atlantic Forest in all samples and a relatively low representation of mangrove pollen, suggesting distant (regional) fluvial transport. Avicennia and Rhizophora were represented in those samples closer to the intertidal zone, Rhizophora being the most important. It was possible to verify a marked difference in pollen concentration/deposition among the three rivers, probably related to the different hydrodynamic pattern of each river. A low concentration of palynomorphs occurred in the Macacú-Guapimirim River, resulting from its higher flow, and there was a high deposition of palynomorphs in the sediments of Guaraí River, in response to its isolation from the hydrographic Guanabara Bay basin. It was possible to verify other interesting data, such as low palynomorph concentration in samples from near the mouth and an increase of palynomorphs in the upstream samples, mainly due to the more active action of the tidal currents. Meanwhile, the increase in the total concentration of the palynomorphs in the upstream samples coincides with the maximum reach of the saline waters and their meeting with the internal flow of the rivers. [ABSTRACT FROM AUTHOR]

Micropalaeontological analyses of two sediment cores (T_A and T_D) collected from a tropical bay in Brazil were conducted. Continental palynomorphs and carbonised particle data were associated with stable isotopes (C and N) assessed using 14C dating. The main objective was to integrate these data with the results of isotopic analyses in order to establish the palaeoenvironmental dynamics of the area during the Holocene. The samples were sub-sampled every 10 cm and then submitted for standard methodological processing for each analysis. The T_A sediment core was dated at three depths, and the oldest depth, 150 cm, had an age between 7241–7339 cal yr BP. The T_D sediment core had an age between 6778 and6948 cal yr BP at its deepest depth, 370 cm. Using radiocarbon dating and micropalaeontological analyses, the integrated assessment of the two sediment cores indicated that the core with a coarser granulometry core was a continuation of the core with the finest granulometry. Consequently, both the lithological change and the preservation of the microfossils could be directly related to periods of sea level variations observed in the coastal region of Brazil. [ABSTRACT FROM AUTHOR]

The aim of this study was to obtain data on the production and verify the adequacy, based on Brazilian legislation, of practices adopted during the processing of bee-pollen collected in nine Brazilian states; and, to identify the perception of the beekeepers about the vegetation visited by bees. The data were obtained from the beekeepersusing a questionnaire and, in the laboratory, the moisture content and the botanical origin of the 69 samples were identified. It was observed that the number of productive hives per apiary ranged from 3 to 300.The frontal type collector was used by all producers who answered this question. The interval between the collection and the dehydration of the samples varied between apiaries and only two samples were lyophilized, while the others were dehydrated in an electric oven. Part of the samples was dehydrated under temperature above the limit established in Brazilian legislation, and 91% of the analyzed products had moisture content above 4%. No food additives were used at any stage of the process. Pollen analysis indicated that, in some cases, the producers were able to identify the plants visited by bees. It is concluded that, the production of bee-pollen was performed by small or medium beekeepers, which adopt different practices of production and processing, respecting the non-use of additives, however, with failures in terms of dehydration temperature and moisture content in the final product. Moreover, when producers carefully observe the collection of pollen by bees, they are able to perceive the polliniferous sources. [ABSTRACT FROM AUTHOR]

Sixty-one samples of dried bee pollen collected from various apiaries in the southern Brazilian macro-region were examined to detect the botanical origin of the pollen and to enable more accurate product certification. The palynological analysis of the samples followed the standard methodology and was conducted without the use of acetolysis. The samples were washed once or twice with ethanol and then with water. The sediment obtained was homogenised in a water/glycerine solution for microscopic observation. The target number of pollen grains to be counted was 500 pollen grains or more per sample. The results demonstrated that 35 samples consisted of a unique pollen type representing more than 90% of the pollen sum (or more than 60% if no accessory pollen was present). These samples were considered monofloral. Several pollen types grouped in a sample were related to heterofloral pollen batches. The most frequent pollen types were ofMimosa scabrella, Eucalyptus, Andira, Machaerium, MyrciaandPiptocarpha. The results of the current study were related to the surrounding vegetation of the apiaries and reflected the resources available to the bees. Furthermore, these results are relevant to apicultural activities and are commercially significant. [ABSTRACT FROM PUBLISHER]

Bee pollen (BP) has been increasingly studied because it contains a wide variety of bioactive compounds, including vitamins. Brazilian botanical diversity, together with the potential of local beekeeping production, makes BP's capacity as a food source of bioactive compounds major focus for research. In this scenario, the objective of this study was to screen and evaluate the chemical composition, including antioxidant vitamins, of BP samples from southern Brazil, and to correlate them with their botanical origin. Analyses of nutritional composition were performed to compare them with the quality parameters established by Brazilian and international regulations. Additionally, individual sugars and vitamins (C, E and pro-vitamin A) were quantified and microscopic analysis for taxon classification was performed to correlate with vitamins and nutritional composition. The results of the chemical analysis showed that the samples were in accordance with the relevant regulations. The composition of vitamins and pollen types varied among the samples. Some BP could be classified as a source of a particular vitamin in a standard dose (25 g). Lipid and protein content from Rio Grande do Sul presented higher mean values (p < 0.05) compared with the other two states. Some correlations between chemical composition and botanical taxon were observed. Principal component analysis showed that the samples from the states of Rio Grande do Sul and Paraná presented similarities in terms of composition for each location. HCA and PLSDA were not able to classify the samples based on the chemical markers used. The analysis of vitamins confirmed that BP from this region can be a good source of antioxidant vitamins and that it can provide important nutritional information to food researchers and bioactive compounds for consumers. [ABSTRACT FROM AUTHOR]

Twenty-four samples of Apis mellifera honey and twenty-four samples of Melipona subnitida (Jandaira) honey were collected in the northeast of Brazil. Moisture, hydroxymethylfurfural, free acidity, insoluble solids in water, diastase activity, ashes, electrical conductivity, proteins, lipids, total carbohydrates, energy and sugars were the parameters analysed. The efficiency of the qualitative tests ( Fiehe's test, Lugol's reaction, Lund's reaction) was tested. Pollen types and the corresponding plant species were identified in all samples (3 in Apis and 1 in Melipona). Apis mellifera honey samples demonstrated parameters in accordance with the Brazilian Legislation, while the Melipona subnitida honey samples displayed moisture (24.80%) and diastase activity (null) in discordance with the established by the regulation for Apis mellifera honeys. Apis honey samples presented higher values of electric conductivity (284.00 μS cm−1) than the obtained from the Jandaira honey samples (102.77 μS cm−1) as well as a darker colour (26.67 mmPfund) when compared with Jandaira honey (7.00 mmPfund). The concentration of the glucose, fructose and sucrose was higher in the Apis honeys than in the Jandaira honey. The characteristics of the two types of honey were very different, highlighting the need of developing specific legislation for stingless bees' honey. [ABSTRACT FROM AUTHOR]