Influência de fatores biogeográficos e variáveis bioclimáticas na composição, diversidade e estrutura filogenétia em brejos de altitude

Abstract

Understanding how and which environmental factors influence the mounting and structure of plant communities is one of the enormous challenges of ecology. And for better perception, historical aspects also need to be taken into account. Ecophylogenetics has emerged as a helpful tool to characterize better communities about their evolutionary histories. It is possible to approach the relationship between environmental factors and evolutionary history from the appraisal of the phylogenetic structure in plant communities. From this, we verified whether the distance from the coast, area size, and bioclimatic variables influence the diversity and phylogenetic structure of plant communities in the Altitude Marshes located in the northeast region of Brazil. We expect that: 1) larger areas closer to the coast will have a higher richness and phylogenetic diversity than smaller and more inland areas; 2) areas with higher precipitation rates and lower temperatures have greater phylogenetic diversity. This research comprises a budget of 9 areas of Altitude Marshes distributed in the states of Ceará, Paraíba, Pernambuco, and Alagoas. The areas have an altitude of 600m and an annual average minimum of 814 mm. The phylogenetic structure and mounting of communities were quantified from the richness, PD (Phylogenetic Diversity of Faith), ses.MPD (Mean Pairwise Distance – MPD) and ses.MNTD (Mean Pairwise Taxon Distance – MNTD). The Generalized Model Analysis was performed for the relationship of richness, PD, ses.MPD (Mean Pairwise Distance – MPD) and ses.MNTD Near (Mean Pairwise Taxon Distance – MNTD) with the distance of the areas to the coast, area size, and bioclimatic variables (Annual Mean Temperature, Mean Diurnal Range, Isothermal, Temperature Seasonality, the maximum temperature of the hottest month, minimum temperature of the coldest month, Annual Temperature Range, the average temperature of the wettest quarter, the average temperature of the warmest quarter, the average temperature of the coldest quarter, Annual Precipitation, Rainfall of the wettest month, Rainfall of the driest month, Precipitation seasonality, Precipitation of the wettest quarter, Rainfall of the driest quarter, Warmer Quarter Precipitation and Coldest Quarter Precipitation). The results show that historical processes and environmental factors influence the structure, composition, and phylogenetic diversity of Brazilian Altitude Marshes areas. Species richness and PD have a significant positive relationship with bioclimatic variables such as precipitation in the warmest quarter, precipitation in the coldest quarter, and a negative rapport with distance from the ocean. The ses.MPD has a significant negative rapport with temperature seasonality and a positive relationship with precipitation in the wettest month, and the size of the area. The ses.MNTD has a significant negative relationship with isothermality, and a positive relationship with the mean diurnal range and annual precipitation. These results can serve as a basis for raising important discussions on the future of the biodiversity of these areas in the face of climate change and on conservation.