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Geosites in syn- and post-collisional granitoid rocks of the Rio Doce Magmatic Arc are important markers of the tectonic environments associated with the amalgamation of the western portion of Gondwana during the Neoproterozoic. Another aspect that stands out in these geosites is the relief that resulted from the breakup of Pangea with the opening of the South Atlantic Ocean and the action of the climate propitiating the alteration of the rocks and the soil erosion during the Cenozoic, leaving a landscape full of inselbergs that allow us to reach minerals, rocks, and structures that were formed between 630 and 480 Ma. The morphology of syn-collisional granitoid geosites is controlled by NNW-SSE fractures of Colatina lineament, and secondarily, by a shear fracture pair of WNW-ESE and WSW-ENE directions. In post-collisional granitoid geosites, the main control is the shape of the intrusion, and secondarily, a pair of shear fractures of WNW-ESE and WSW-ENE directions. The State of Espírito Santo has a strong connection between rural communities and cities with the local geology. Several initiatives to preserve this landscape can be noticed in the different tourist areas, such as the Pontões Capixabas Natural Monument and Pedra Azul State Park. Espírito Santo is a good example of geoconservation in Brazil, but at the same time, it needs to be aware of its geotourism potential, which can contribute to the local rural communities. For this, actions are needed to spread geological knowledge in schools, by training guides and taking this information to rural communities through new routes and using existing routes combined with geological knowledge, geodiversity, and cultural manifestations of the region. [ABSTRACT FROM AUTHOR]

The municipality of Boa Nova, in northeastern Brazil, is in an ecotone zone between the Caatinga and Atlantic Forest phytogeographic domains. The transition phytophysiognomy is seasonal forest and known locally as mata de cipó. In these phytophysiognomies there are lajedos, which are rock outcrops colonized by vegetation well-adapted to extreme microclimatic variation and vegetation diversity is affected by the vegetation types of the surrounding areas. Due to the singularity of these environments and the relevance of floristic studies for conservation, this work aimed to identify the species richness and compare the similarity of the flora on four rock outcrops in Boa Nova. The flora was surveyed during exploratory walks along lajedos between 2016 and 2019. In total, 162 species were identified on the Boa Nova outcrops. The flora has a composition and structure similar to semiarid outcrops, as well as endemic species that also occur in surrounding phytophysiomies. Despite the proximity, a similarity index revealed there is floristic dissimilarity between the areas. Nine new occurrences were recorded for the region, five species are threatened with extinction (Aosa gilgiana, Ficus cyclophylla, Hippeastrum stigmovittatum, Pleroma caatingae and Trixis pruskii), and 43 species are common in anthropogenic areas. This reinforces the importance of actions to conserve these areas. [ABSTRACT FROM AUTHOR]

The characterisation of geoheritage and the understanding of the physical and socio-cultural features of a territory are essential to achieve the major geoconservation goals: protection and sustainable use of exceptional elements of geodiversity. This research was done in the Sertão Central, an economic vulnerable area in the hinterland of northeast Brazil, remarked by the Caatinga Biome and a rocky, semiarid landscape. The area comprises an assemblage of deformed igneous and metamorphic rocks, such as gneisses, TTG rocks, schists, and granites. Starting from a regional geoheritage inventory done in 2015, fourteen geosites were selected and assessed, representing a wide regional tectonic evolution from the Precambrian West Gondwanan orogenesis to the Cenozoic development of particular examples of Brazilian granitic inselbergs. In addition to the inventory of geosites, six geodiversity sites were also evaluated, along with five geocultural sites, highlighting the cultural value of geodiversity in the area. Based on the available information, an analysis with the main features and spatial configuration of the geoheritage was developed, allowing to designate the most appropriate use for each geological site. Considering geoconservation as a geoscientific fostering for the sustainable development, our study suggests a set of general guidelines for the management of geoheritage, in order to facilitate the decision-making process by local managers and stakeholders as well as to promote the discussion on geotourism strategies for the region. Organised according to well-defined geoconservation strategies, these guidelines could enhance the sustainable development of vulnerable regions, such as Sertão Central itself. [ABSTRACT FROM AUTHOR]

This paper subscribes to the concept of Key Geoheritage Area (KGA) which is currently being developed. Three localities in northeast Brazil are described as possible candidates for KGA. They represent the diversity of erosional granite landscapes found in cratonic areas. Pedra da Boca is an impressive cluster of tall domes rising from the marginal escarpment of Borborema Plateau, with gigantic tafoni. Pai Mateus is located on the Borborema Plateau and consists of a group of low granite elevations (ruware, whalebacks) with residual boulders scattered on their surfaces. These boulders are hollowed out by weathering, providing another very distinctive type of tafoni. Quixadá area is an inselberg landscape, with a few dozens of bedrock hills rising from the plain. Among minor features, karren are ubiquitous. Collectively, these three sites show different types of cratonic granite scenery, a multitude of medium-size and minor geomorphic features, and illustrate pathways for inselberg formation and decay through long-term weathering and erosion. Therefore, they are considered to fit the concept of KGA. In addition, each landscape has considerable aesthetic and scenic values, with great potential for geotourism and geoeducation. Nevertheless, their current conservation status is low and geointerpretation nearly nonexistent and these challenges are to be addressed in the future. [ABSTRACT FROM AUTHOR]

Andorinhas Hill is an integral part of the Serra da Tiririca State Park rocky outcrop complex and is located in the municipality of Niterói, RJ. The colonization by exotic plants was evaluated based on point-transect and intercept-line techniques. On the main trail, the plants were registered with the GPS aid, and their presence was recorded in two circular plots of five meters on both sides of the trail, at horizontal intervals of 100 m, totaling 19 intervals. Each species cover values were estimated according to Braun-Blanquet scales, considering five classes: C1 (10%), C2 (25%), C3 (50%), C4 (75%) and C5 (100%). In the adjacent tracks, twenty transects were stretched, perpendicularly arranged to the main trail and the line length that was intercepted by each exotic species was taken note. With the obtained values in the two techniques, the phytosociological parameters were calculated. From the point-transect technique 15 invasive species were collected, belonging to 13 families and 15 genus. The species with the highest frequency and coverage values were Megathyrsus maximus, Hibiscus rosa-sinensis, Furcraea foetida e Euphorbia umbellata. In turn, the line intercept technique showed eight species belonging to five families. The species of most importance were F. foetida, Phyllostachys aurea, Oeceoclades maculata, M. maximus e Tradescantia zebrina. Of the exotic species total number, those with invading characteristics are Furcraea foetida, Megathyrsus maximus and Phyllostachys aurea which are cultivated in the surroundings, along the trails and established on the outcrop. [ABSTRACT FROM AUTHOR]

The Atlantic forest is among the hottest hotspots for biodiversity conservation. Within this biome, inselbergs are isolated granitic and gneiss rocks that rise sharply above the lowland surrounding forests. Due to prevailing stressful conditions and resource paucity of inselbergs, distinguished plant communities are formed in these rocky-associated vegetation, which comprise unusually high levels of endemic and threatened species. Here, we evaluated the importance of competitiveness:stress-tolerance:ruderalism ecological strategies in different vegetation patches on the inselberg, tested for a connection between patch structure and functional traits, and compared the variation in functional traits between native and an exotic species, which represents a major threat to inselberg communities. Despite the stressful conditions of inselbergs, we found a relatively high diversity of ecological strategies, but most species and patches lied between the S and C strategy. The invasive Melinis repens, in turn, was functionally distinctive from native communities, with the predominance of traits associated with ruderalism. We also found that most functional traits significantly correlated with at least one environmental driver, highlighting their role in structuring plant communities in this heterogeneous environment. Since inselberg patches were spatially heterogeneous, and the variation in resource availability implies in favouring different ecological strategies, some patch types were more invasive-prone than others. Our data provide significant advances for identifying the environmental drivers of biological invasion in resource-limited environments. We argue that further trait-based approaches will become critical for developing conservation and management strategies for inselberg plant communities, especially in the context of rapid habitat loss and fragmentation of the Atlantic forest. [ABSTRACT FROM AUTHOR]

Plants often combine multiple strategies to achieve pollen transfer. The dioecious Clusia nemorosa (Clusiaceae) produces floral resin, a specialized reward for resin-collecting bees. It also exhibits floral automimicry with female flowers mimicking male flowers in order to attract pollen-collecting insects. We observed the hourly visitation frequency and behaviour of bee visitors on two rock savanna sites in French Guiana. The major strategy in pollen transfer and the variation in visitation rates among visitor species were examined. We hypothesized that the visitation rate will vary between the floral sexes and degree of this variation will differ between the two-reward systems. We found no evidence for visits being exclusively related to resin collection, which we expected to be the principal strategy in pollen transfer. Deceit pollination appeared to have minor importance and seemed to be locally associated with the site, where demand for pollen was greater. Flower visits that probably facilitated most pollen transfer, combined resin and pollen. The pollinators involved in this system collected pollen from male flowers and resin from female flowers. The fruit set was not particularly low (44.19%) so offering different rewards by different flower genders has not constrained reproductive success in this system. Pronounced variation in visitation rates between sexes was not related to the pollination mechanisms but to the demand for the two rewards. Overall demand for pollen was greater than demand for resin. Female flowers were visited much less frequently than male flowers. Peak pollen collection occurred in the morning, i.e., as soon as the resource was available, while resin was collected throughout the day. There was a local variability in demand for the two resources because both the visitation rate and the behaviour of foraging bees varied between the two observation sites. [ABSTRACT FROM AUTHOR]

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Studies of organisms on ‘terrestrial islands’ can improve our understanding of two unresolved issues in evolutionary genetics: the likely long-term effects of habitat fragmentation and the genetic underpinnings of continental species radiations in island-like terrestrial habitats. We have addressed both issues for four closely related plant species of the adaptive radiation Bromeliaceae, Alcantarea imperialis, A. geniculata, A. regina and A. glaziouana. All four are adapted to ancient, isolated inselberg rock outcrops in the Brazilian Atlantic rainforest and are thus long-term fragmented by nature. We used eight nuclear microsatellites to study within-population spatial genetic structure (SGS) and historical gene dispersal in nine populations of these species. Within-population SGS reflected known between-species differences in mating systems. The strongest SGS observed in A. glaziouana (Sp=0.947) was stronger than literature estimates available for plants. Analysis of short- and long-distance components of SGS identified biparental inbreeding, selfing and restricted seed dispersal as main determinants of SGS, with restricted pollen dispersal by bats contributing in some localities. The ability of Alcantarea spp. to colonize isolated inselbergs probably stems from their flexible mating systems and an ability to tolerate inbreeding. Short-ranging gene dispersal (average sigma=7–27 m) is consistent with a loss of dispersal power in terrestrial island habitats. Population subdivision associated with sympatric colour morphs in A. imperialis is accompanied by between-morph differences in pollen and seed dispersal. Our results indicate a high potential for divergence with gene flow in inselberg bromeliads and they provide base-line data about the long-term effects of fragmentation in plants.Heredity (2008) 101, 285–296; doi:10.1038/hdy.2008.65; published online 23 July 2008 [ABSTRACT FROM AUTHOR]

Plant species diversity is surveyed in the southern part of the Taï National Park (TNP), Côte d'Ivoire. This park is the largest remaining tract of pristine forest in the West African rainforest biodiversity hotspot. Plant assemblages and environment factors were surveyed in 39 temporary 625-m² plots within three areas. The species list was completed thanks to itinerant prospections. TWINSPAN classification and detrended correspondence analysis were applied to the 39 relevés. We recorded a total of 916 plant species, including 169 West African endemics, that rises the floristic richness of TNP in 1233 species. Most plant species recorded were Guineo- Congolian species (90.9%) among which 8% were 'Sassandrian species', i.e. endemics of the extreme southwest Côte d'Ivoire. Eight of these endemics were exclusive of the southern part of TNP. The forest is very species-rich, particularly in Rubiaceae, Leguminosae and Euphorbiaceae. Most of the sampled species (59.5%) were erect phanerophytes with a dbh ≤ 10 cm. We distinguished 7 plant community types, mainly determined by geomorphology and disturbance history. Lowland forests were typical dense evergreen forests with different degrees of maturity related to historical human impact. Inselbergs and swampy depressions provide an original azonal vegetation. We conclude that the southern part of TNP contributes significantly to the regional biodiversity hot- spot since it includes the last remnants of primary evergreen rainforest and contains species assemblages from both higher rainfall biomes on moist soils derived from schist parent material and lower rainfall biomes on inselberg slopes and top. As anthropogenic disturbance clearly reduces biodiversity, these last remnants should be integrally protected. [ABSTRACT FROM AUTHOR]

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We examined avian communities of kopjes (naturally occurring insular rock outcrops) in grassland and thorn tree woodland habitats in the Seronera region of Serengeti National Park, northwestern Tanzania. Although kopjes cover a small proportion of the Park's area, they provide resources that are uncommon in the Serengeti landscape and are known to host diverse, yet poorly documented, biotic communities. The primary objectives of this study were (1) to compare avian communities of kopjes with those of their surrounding habitat matrixes; (2) to compare the avian communities among kopjes; and (3) to determine the effects of kopje characteristics (e.g., size, vegetation cover, level of human disturbance and matrix type) on avian diversity and community composition. The avian communities of kopjes differed significantly from those of the matrixes in species composition and guild characteristics. Rare species, frugivorous species and nectarivorous species were more abundant on kopjes, whereas there were more ground-feeding species in matrix sites. Species richness was positively correlated with the area of kopjes covered by tall vegetation (5+ m), but neither total habitat area nor total vegetation cover significantly affected avian diversity. The surrounding habitat type, the fruiting phenology of Ficus and Commiphora trees and the level of human disturbance also influenced the presence and abundance of individual species and accounted for differences in community composition among kopjes. Our results show that kopjes support unique avian assemblages comprising many species that are otherwise rare in Serengeti, and consequently that kopjes may be local hotspots of avian diversity in the region. [ABSTRACT FROM AUTHOR]