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The Araucaria Plateau is a geomorphological unit that occupies approximately three-quarters of the terrain in the southern region of Brazil. The plateau displays different altitudinal levels (600 to <1400 m a.s.l.) that are locally recognized as remnants of planed surfaces (S8-S1). These surfaces are maintained by basic (S3-S8) and acidic (S1 and S2) volcanic flows from the Neocretaceous period of the Paraná Basin. The largest extent of this plateau is located in a humid subtropical climate zone. Colluvial, colluvial-alluvial, alluvial sediments and paleosols (Ab diagnostic horizons) occur predominantly in S2. The paleosols are located in low-hierarchical-order fossil valleys (first- to fourth-order in Strahler's stream classification) and valley heads, which are referred to as paleovalleys in this paper. We employed these paleosols as stratigraphic level markers of the pedogenesis of the regional Upper Quaternary and propose their importance as records of the paleoenvironmental conditions of the Araucaria Plateau in areas above 1200 m a.s.l. These paleosols were dated by 14C and show ages between 23.8 ± 0.05 kyr BP (28.06-29.08 kyr cal. BP) and 41.16 ± 0.48 kyr BP (44.13-45.58 kyr cal. BP). The calibrated ages are related to Marine Isotope Stage 3 (MIS 3), in which the last period of global warming occurred (approximately 60-25 kyr cal. BP). We integrated the morphological, pedogeochemical, clay fraction mineralogy, micromorphological and δC-13 analyses of five paleosols from S2 to verify the paleoenvironmental conditions of the Araucaria Plateau and its correspondence with the paleoclimatic phenomena that were identified on a global scale during MIS 3 in the Southern Hemisphere. We obtained the following conclusions: a) the properties of paleosols reflect pedological processes that are adjusted to the paleoenvironmental conditions at the end of MIS 3 and the transition to MIS 2 (Last Glacial Maximum); b) aplasmogenic partial acidolysis was the predominant pedogeochemical process during MIS 3; c) during this period, the water regime was sufficiently humid to develop hydromorphic horizons in the valley bottoms of the entire drainage network to the valley heads; d) regional change toward a drier hydric regime occurred in MIS 2, when erosion of the paleosols predominated; and e) in MIS 1 (current Holocene interglacial), burial of the paleosols and relief inversion occurred, which resulted in fossilization of the valleys. [ABSTRACT FROM AUTHOR]

Abstract: Lapa das Boleiras rockshelter, a Paleoamerican archaeological site in Central Brazil, was intensely occupied by humans from 10,000 14C BP (11.8calkyrBP), until approximately 7500 14C BP (8.4calkyrBP). In this paper we present some interpretations about the formation processes operating on the site. One of our main conclusions is that the bulk of accumulated sediments at the site is of anthropogenic origin: they are constituted by volumetrically significant quantities of plant ash remains, what is somewhat unexpectedly in view of prevailing models about the lifestyle of Paleoamerican hunter–gatherers in South America. The evidence we discuss below is also consistent with paleoenvironmental data that suggest a dry period during the mid-Holocene in the region, probably leading to a decrease in human occupation [Araujo, A.G.M., Neves, W., Piló, L.B., Atui, J.P., 2005. Holocene dryness and human occupation in Brazil during the ‘Archaic Gap’. Quaternary Research 64, 298–307]. We surmise that both factors underpin a surprising reduction in sediment accumulation at the site during the mid-Holocene. [Copyright &y& Elsevier]

Stemodia sensu lato is one of the largest genera of the Gratioleae (Plantaginaceae). Recent phylogenetic studies corroborated the paraphyly of Stemodia in its traditional circumscription and suggested the segregation of S. stellata from this genus. This species belongs to a morphologically cohesive group along with S. cipoensis, S. harleyi and S. lobata, all endemic to the Espinhaço Range, eastern Brazil. In this study, we tested the monophyly and interspecific relationships of this group by reconstructing its phylogeny, based on sequences of three cpDNA regions (rps16 and trnL introns and the trnL–trnF intergenic spacer), and one nrDNA region (ITS1 spacer), using Maximum parsimony and Bayesian inference. The monophyly of the 'S. stellata group' was confirmed, and its segregation from Stemodia corroborated. We propose Lapaea as a new genus to accommodate its species, with subsequent four new combinations: L. cipoensis, L. harleyi, L. lobata, and L. stellata. Additionally, we describe and illustrate L. rubriflora, a remarkable red-flowered new species, based on morphological and micromorphological evidence. Lastly, a taxonomic revision of the species recognized in Lapaea is presented, providing an identification key, photos, descriptions, distribution map and notes on their morphology, geographic distribution, habitat, ecology, and conservation status. Lapaea is restricted to the Espinhaço Range comprising five threatened species, each of them with a narrow distribution and phylogenetic relationships consistent with biogeographic provinces. [ABSTRACT FROM AUTHOR]

Itatiaia National Park was the first conservation unit created in Brazil and houses an important remnant of the Atlantic Forest in the Serra da Mantiqueira. The pollen morphology of six species that occur in this locality was analyzed. Pollen material was submitted to acetolysis, measured and photographed, and the data submitted to statistical treatment including multivariate analyses. In addition, pollen grains were submitted to scanning electron microscopy in order to perform a more detailed examination of sexine ornamentation. The results revealed small pollen; subprolate only in S. erecta and prolate spheroidal in the other species; 3‐colporate; sexine ornamentation varying among microreticulate‐striate, rugulate‐striate and striate. Cluster analysis revealed that Ouratea and Sauvagesia form distinct groups. Although the qualitative characters overlap, the genres Ouratea and Sauvagesia are clearly differentiated in multivariate analysis based on metric variables. This work provides, for the first time, descriptions of pollen morphology for Ouratea camposportoi. It can be concluded that the most informative pollen attribute for species delimitation was sexine ornamentation. Palynology proved to be a useful tool for delimiting species, thus aiding taxonomic studies of Ochnaceae. [ABSTRACT FROM AUTHOR]

Mantiqueira Range is the most important headwater region in southeastern Brazil, being responsible for streamflows that feed a significant part of Brazilian hydroelectric energy production. This region is extremely fragile with endemic species like those that compose the upper mountain cloud forest (UMCF), and the dominant soils are typical Inceptisols. These forest environments are rapidly disappearing in Brazil. The changing land use combined with shallow Inceptisols lead to important effects on hydrology. Therefore, studies addressing streamflow behavior in these landscapes are urgently needed for understanding the groundwater recharge process. The objectives of this study were to investigate the role of shallow Inceptisols linked to the land use changes in the streamflow behavior of the Mantiqueira Range region and to understand the mechanisms of water flow into the saturated zone. To validate the study, a comparative analysis was developed for a representative watershed of Mantiqueira Range, whose land use is divided into pasture and Atlantic Forest, known as Lavrinha Creek Watershed (LCW) and a typical UMCF located inside of LCW. The results showed that in general, UMCF has greater potential for water percolation beginning from the surface layer towards the saturated zone. Micromorphological soil images provided useful information about the soil pore system associated with the physical properties of Inceptisols, and this background helped to understand the water recharge process and streamflow behavior. In addition, the water balance for two years (2009-2011) in the UMCF showed that the flow stored in the saturated zone occurs rapidly, increasing its potential for storage, characterized by the process of refilling water in the Inceptisols soil profile under forests in this region. [ABSTRACT FROM AUTHOR]

Brazilian shell sites are largely considered to have been multifunctional and the location of both sacred and secular activities. This article explores the joint contribution that zooarchaeological and geoarchaeological analysis can bring to understanding the depositional history of shell sites and their functions. This combined approach is applied to the study of two shell mounds that represent important aspects of the diverse array of shell sites found along the southern Brazilian coast. Jabuticabeira II is a monumental shell mound that has shown unquestionable evidence of being used mainly as a cemetery, and Encantada III is a smaller shell deposit whose function is more difficult to define. Research focusing on formation processes at Jabuticabeira II played an important role in developing a better understanding of the mortuary rituals performed at the site. In Encantada III, zooarchaeology and geoarchaeology contribute to a better characterization of its role as a short-term deposit of long-lasting permanence. Both shell sites and their practical and symbolical attributes represent examples of the complex dynamics of the anthropic construction of a landscape. [ABSTRACT FROM AUTHOR]