Temporal and spatial variation of floral resources of woody species in a vereda ecosystem: Uniformity and habitat complementarity

Abstract

Floral resource distribution, pollinator community structure, and flowering season are essential for maintaining and preserving pollination services in ecosystems. In humid Cerrado areas, veredas are considered hygrophilous communities, marked by the presence of the Mauritia flexuosa palm tree emerging in the wetter zones. Waterlogged portions present dense hygrophilous forests, whereas open areas predominant present herbaceous and shrubby components. We identified the pollination syndromes of woody species in a vereda ecosystem and characterized the pollination resource availability between habitats (hygrophilous forest and open area). The study was conducted on a vereda located in the north of Minas Gerais, Brazil. We characterized pollination syndromes using information on floral attributes, pollinator observations, and a literature survey. We performed phenological monitoring for 24 months and examined the occurrence of flowering using circular statistics. The differences in pollination syndrome occurrence among months and habitats were determined using modularity analysis. We found eight pollination syndromes, with melittophily being the most frequent pollination type among the woody species in the studied vereda. Flowering occurs throughout the year in the community and peaks from September to November during the transition from the dry to the wet season. In hygrophilous forest the species flowered preferentially in November, whereas in open area, preferentially between September and October. The syndromes distribution differed between the habitats, as well as resource availability. This difference between habitats can influence pollinator diversity. Modularity showed complementarity among the habitats, with continuous resource availability throughout the entire ecosystem. Species present in the hygrophilous forest provide their resources mainly during the rainy season, whereas species from the open area, during the dry season. Information on these interactions is necessary to understand the functionality of a vereda ecosystem, through the characterization of the resource's availability, and maintenance of pollination services in the ecosystem. In addition, our results demonstrate the importance of the vereda ecosystem as an important area in the availability of resources for the Cerrado formation. This information can strengthen protection laws and contribute to sustainable practices that boost the conservation of pollinators in the biome.