The Cerrado plant species present periodic variations in its growth and reproduction usually closely related to climate seasonality. This study aimed to compare the reproductive phenology (flowering and fruiting) of plant species from a dry and a wet grassland in a Cerrado (Brazilian savanna) area at southeastern Brazil (Itirapina, SP) in order to answer the following questions: (i) do the plant species of each physiognomy flower and fruit seasonally? (ii) are the phenological patterns similar, in each physiognomy, among different life forms? (iii) do the physiognomies differ in respect to the proportion of species according to seed dispersal modes? (iv) do the physiognomies differ in respect to the fruiting patterns according to seed dispersal modes? (v) is the reproductive phenology of the species in each physiognomy, according to its life forms and dispersal modes, correlated to the climatic seasonality? We analyzed the vouchers included in the collection of the Herbarium of the Instituto de Biociências de Rio Claro, Universidade Estadual Paulista -UNESP from 1983 to 2005. The plant species were classified into life forms (woody and herbaceous) and dispersal modes (anemo, auto and zoochorous). In both physiognomies the phenological patterns were very seasonal, usually with a peak during the wet season, but differing according to the life form and dispersal mode. The observed differences were related to the environmental conditions of each physiognomy, mainly to the patterns of soil drainage. Phenological patterns were largely influenced by life forms, but the dispersal modes did not show the expected fruiting patterns, based on other studies of different Cerrado areas, emphasizing the importance of conducting detailed field phenological studies in dry and wet grasslands.

Flowering patterns are crucial to understand the dynamics of plant reproduction and resource availability for pollinators. Seasonal climate constrains flower and leaf phenology, where leaf and flower colors likely differ between seasons. Color is the main floral trait attracting pollinators; however, seasonal changes in the leaf-background coloration affect the perception of flower color contrasts by pollinators. For a seasonally dry woody cerrado community (Brazilian savanna) mainly pollinated by bees, we verified whether seasonality affects flower color diversity over time and if flower color contrasts of bee-pollinated species differ between seasons due to changes in the leaf-background coloration. For 140 species, we classified flower colors based on human-color vision, and for 99 species, we classified flower colors based on bee-color vision (spectral measurements). We described the community’s flowering pattern according to the flower colors using a unique 11 years phenological database. For the 43 bee-pollinated species in which reflectance data were also available, we compared flower color diversity and contrasts against the background between seasons, considering the background coloration of each season. Flowering was markedly seasonal, peaking at the end of the dry season (September), when the highest diversity of flower colors was observed. Yellow flowers were observed all year round, whereas white flowers were seasonal, peaking during the dry season, and pink flowers predominated in the wet season, peaking in March. Bee-bluegreen flowers peaked between September and October. Flowers from the wet and dry seasons were similarly conspicuous against their corresponding background. Regardless of flowering season, the yellowish background of the dry season promoted higher flower color contrast for all flower species, whereas the greener background of the wet season promoted a higher green contrast. Temporal patterns of flower colors and color contrasts were related to the cerrado seasonality, but also to bee’s activity, visual system, and behavior. Background coloration affected flower contrasts, favoring flower conspicuousness to bees according to the season. Thus, our results provide new insights regarding the temporal patterns of plant–pollinator interactions.

Summary Genetic divergence between species depends on reproductive isolation (RI) due to traits that reduce interspecific mating (prezygotic isolation) or are due to reduced hybrid fitness (postzygotic isolation). Previous research found that prezygotic barriers tend to be stronger than postzygotic barriers, but most studies are based on the evaluation of F1 hybrid fitness in early life cycle stages. We combined field and experimental data to determine the strength of 17 prezygotic and postzygotic reproductive barriers between two Lysimachia species that often co‐occur and share pollinators. We assessed postzygotic barriers up to F2 hybrids and backcrosses. The two species showed near complete RI due to the cumulative effect of multiple barriers, with an uneven and asymmetric contribution to isolation. In allopatry, prezygotic barriers contributed more to reduce gene flow than postzygotic barriers, but their contributions were more similar in sympatry. The strength of postzygotic RI was up to three times lower for F1 progeny than for F2 or backcrossed progenies, and RI was only complete when late F1 stages and either F2 or backcrosses were accounted for. Our results thus suggest that the relative strength of postzygotic RI may be underestimated when its effects on late stages of the life cycle are disregarded.

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Key message Forest fragmentation leads to a micro-environmental condition that favors the proliferation of liana, which infest trees, compete with them, and reduce their performance. To report the state of the art of the main actions to manage this structural component of tropical forests, we surveyed the control strategies in the literature in the last 71 years, highlighting research goals, tree-climber interactions, management, restoration, and conservation. Dataset access is at https://doi.org/10.5281/zenodo.6678112. Associated metadata are available at https://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/712ff481-dfa2-4ddb-b4fa-fcbd7c517842 Context Lianas (woody vines) are considered structural parasites of tropical trees because they start their development as terrestrial seedlings but need to reach a tree canopy for higher light availability. The tree-liana coexistence usually can damage tree species, thus removing lianas has been suggested as an alternative to reinforce forest regeneration. Aims The dataset compilation begun during the first author doctoral work and a first dataset on neotropical lianas was published (https://doi.org/10.5281/zenodo.4050477) in 2020. The present dataset (https://doi.org/10.5281/zenodo.6678112) presents an update of the 2020 dataset with additional amend (published articles from 2018 to 2021) and enhanced metadata descriptions. Our aim is providing an updated database extracted from scientific literature compiling information related to the effect of lianas on tree and forest structure and diversity, and to contribute to improve decision making on forest restoration and management. Methods We made a systematic literature review on lianas in the Neotropical region (native or restored) from 1950 to 2021. First, we selected studies on liana management and described each paper according to the following topics: vegetation status, positive (P), and negative (N) effects of lianas on each species, the species in focus, and the suggested management strategy. Results Almost 83% of the studies pointed out tree-climber interactions as negative to trees. Cutting was the management strategy adopted in 92% of the studies. Controlled burning, enrichment, and selective cutting were adopted in only one paper. Rainy and seasonal forests were the vegetation types with more studied sites (20 and 17 respectively). Only one study suggested enhancing forest diversity through direct seeding of lianas. Four studies evaluated the impact of lianas on forest diversity and forest fauna. Conclusion The data collected showed the different impacts of liana management on the diversity and structure of tropical forests. It can endorse environmental control and management practices and evaluate the consequences of these techniques in recovering forests or improving timber production.

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Modern UAS (Unmanned Aerial Vehicles) or just drones have emerged with the primary goal of producing maps and imagery with extremely high spatial resolution. The refined information provides a good opportunity to quantify the distribution of vegetation across heterogeneous landscapes, revealing an important strategy for biodiversity conservation. We investigate whether computer vision and machine learning techniques (Object-Based Image Analysis—OBIA method, associated with Random Forest classifier) are effective to classify heterogeneous vegetation arising from ultrahigh-resolution data generated by UAS images. We focus our fieldwork in a highly diverse, seasonally dry, complex mountaintop vegetation system, the campo rupestre or rupestrian grassland, located at Serra do Cipó, Espinhaço Range, Southeastern Brazil. According to our results, all classifications received general accuracy above 0.95, indicating that the methodological approach enabled the identification of subtle variations in species composition, the capture of detailed vegetation and landscape features, and the recognition of vegetation types’ phenophases. Therefore, our study demonstrated that the machine learning approach and combination between OBIA method and Random Forest classifier, generated extremely high accuracy classification, reducing the misclassified pixels, and providing valuable data for the classification of complex vegetation systems such as the campo rupestre mountaintop grassland.

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