Myrtaceae juss. Da Serra da Mantiqueira, Sudeste, Brasil: distribuição, serviços ecossistêmicos e conservação

Abstract

Montane regions are structurally heterogeneous formations, and therefore environments of high diversity and endemism. They are highly threatened due to climate change and local factors of biodiversity loss. Serra da Mantiqueira (SM), in southeastern Brazil, is one of these environments, classified with extremely high importance for conservation and whose flora distribution is not well known. Within the various plant formations of the SM, cloud forests are highlighted, presenting countless ecosystem services. Due to complex interactions with clouds or fogs, these forests are considered one of the rarest and most threatened ecosystems in the world. Considering the importance of montane environments and cloud forests for ecosystem services, and the lack of knowledge regarding the distribution patterns for SM and cloud forest species, we use Myrtaceae as a 'model' group for the development of our work. The Myrtaceae family, due to its broad knowledge and importance in Atlantic domain communities, is a fair model for evolutionary and ecological studies, as well as a good predictor for angiosperm diversity. We divided our work into four chapters, with regional-scale analyses for the SM. The first chapter aims to understand how the species are distributed in the altitudinal and soil gradients, through a phytosociological sampling of seven cloud forests patches along with the SM. In the second chapter, through the formed phytosociological database, we sought to quantify the carbon stock in the SM cloud forests, highlighting the hyperdominant carbon species that form the communities along the altitudinal gradient. In the third chapter, we formed a database with all records of Myrtaceae occurring in the municipalities of the SM to verify the patterns of geographical distribution and conservation of Myrtaceae species, sampling effort influence, gaps, and the Conservation Units’ effectiveness in protecting endangered species. Additionally, we listed the 354 Myrtaceae species occurring in the SM. The fourth chapter was developed from the same database. We filtered all Myrtaceae species occurring exclusively in cloud forests for species modeling and predictive analysis. We sought to understand how future climate changes may affect cloud forests in SM and their conservation implications, considering the current vulnerability to climate change of these forests across the planet. In general, we concluded that the species that characterize the studied cloud forests and are the main species in its floristic composition correspond to hyperdominant species in carbon, including threatened species. At the same time, these species belong to lineages or genus that may become threatened with the advance of climate change. Our work brings precious information to underpin conservation strategies for SM, especially for cloud forests, unique environments that perform important ecosystem services, as well as are critical to carbon stocks and extremely sensitive to climate change.