Composição florística e estrutura de comunidades de epífitas vasculares em fragmentos de floresta estacional semidecidual, em Minas Gerais. Preenchendo lacunas na Serra da Mantiqueira

Abstract

It is becoming increasingly clear that the destruction of natural environments and the biotic and abiotic components found within them has led to a significant loss of biodiversity and ecosystem services. This has a profound impact on all species, including humans. Efforts to mitigate the negative effects of measurements are often hindered by a lack of political support. Many biodiversity studies have been conducted in the Brazilian Atlantic Forest, which is one of the world's main hotspots of biodiversity. However, many sites remain undersampled, making it difficult to accurately determine the true dimension of the biological diversity. This knowledge could be useful in the planning of conservation strategies and as an instrument of pressure on decision-makers regarding environmental policies. As a part of a wider research project aiming to sample and analyze the epiphytic flora in some areas of Serra da Mantiqueira, located in Minas Gerais, the current study aimed to evaluate the vascular epiphytes in Seasonal Semideciduous Forest (SSF) areas that have knowledge gaps. This triad was selected based on the following reasons: Serra da Mantiqueira is among the most prominent mountain ranges in Brazil, known for its high biodiversity and relevant ecosystem services, which include the provision of water and food, and it is essential to conduct studies in underrepresented areas, such as those with SSF. This phytophysiognomy covers a large area and has an important part of the biodiversity of the Atlantic Forest. However, it is often overlooked in favor of the rainforests. Vascular epiphytes are also an important group of plants in tropical forests performing relevant ecological functions. Despite an increasing number of studies in Brazil, they are still less studied than other components of the forest, such as trees. In the first chapter of this study, we present a checklist of vascular epiphytes found in a remnant of SSF, located in the municipality of Itamarati de Minas, a place without prior systematic botanical collections. The results confirmed some well-known patterns in the family richness of this synusia, but varying genera and species representations highlight how a SSF’s structure can impact the composition of the epiphytic communities. Furthermore, the area has some endangered, rare, and newly found species in Minas Gerais state. In the second chapter, we analyzed some floristic and ecological parameters of the epiphyte communities in three conservation units. These units are composed of the SSF phytophysiognomy, geographically close, but located at different elevation levels (250 m, 500 m and 1200 m). We conducted an analysis of the vertical distribution of epiphytes in the phorophytes, looking at their similarity, absolute and relative frequencies, as well as their taxonomic diversity. Our findings showed that the crown stratum had the highest number of records, while the analysis of taxonomic diversity suggests that, overall, the areas have reasonable conservation conditions. The analysis of similarity revealed that only two species were present in all three areas, which underscores the uniqueness of the epiphytic communities. Our findings make a valuable contribution to the understanding of the flora in Serra da Mantiqueira region, emphasizing the need and significance of conducting focused studies in areas that are underexplored.