We have analysed the diversity of the late Paleozoic palynoflora of the Paraná (Brazil and Uruguay), Parnaíba and Amazon (Brazil) basins using already published data. In order to do this the total diversity and diversity with range-through approach curves were built up, as well as Foote's appearance and disappearance rates at the generic level. These parameters were also obtained separately for each group of sporomorphs. An important increase in diversity in the Asselian and Sakmarian and a posterior decrease until the Lopingian were observed. The values of the appearance rates were higher than those of disappearance and they peaked in the Asselian, while the highest disappearances took place in the Capitanian and, to a lesser extent, in the Sakmarian. On the other hand, spores and pollen grains show some differences in the general diversity trend. However, there are differences in the patterns of appearance and disappearance. Despite possible biases, mainly related to the collecting effort, the diversity curves and appearance and disappearance rates obtained are congruent with the climatic phases proposed for this region in these periods. The increase in the number of palynomorph genera is associated to the early Permian climatic amelioration whilst a decrease in diversity is related to the beginning of an arid phase.Keywords: Brazil, diversity, Paleozoic, Palynology, Uruguay. tado, resulta difícil asignar afinidades botánicas a muchos palinomorfos. Además, muchos morfotipos diferentes pueden ser producidos por la misma planta (Lindström et al., 1997). Sin embargo, se pueden observar patrones generales que se repiten en las diferentes cuencas ubicadas en diferentes zonas geográficas, que podrían relativizar los sesgos mencionados anteriormente. Por lo tanto, la presente contribución puede ser un aporte válido como una aproximación inicial a la temática de la diversidad en el Paleozoico superior.
: This paper analyses daily and seasonal variations on pollen concentrations and the influence of meteorological conditions on the airborne pollen from June 2011 to May 2014. Data is also compared with results from a previous pollen survey from 2000-2001. Ninety-three taxa were identified, belonging to 49 trees and shrub taxa and 44 herbaceous taxa. The most important pollen sources were Poaceae, Platanus, Cupressaceae/Taxaceae, Eupatorieae type, Celtis, Urticaceae, Myrtaceae, Casuarina, Amaranthaceae, Cyperaceae, Fraxinus, Arecaceae, Ricinus communis, Moraceae, Myrsine, Ambrosia, Quercus, and Pinaceae. Pollen was recorded all year round but the main pollen season was from August to April. Inter-annual differences were observed on pollen indexes, dates and values of daily peak concentrations and monthly accumulated concentrations. Temperature, relative air humidity and wind speed and direction seem to be the most influential meteorological variables on pollen concentrations. The number of days that pollen concentrations are above moderate and high thresholds levels is estimated and woody and non-woody pollen concentrations would be above moderate levels on average 182 days per year.
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