Diversidade fenotípica e predição da distribuição natural de malva (Urena lobata L.) para uso e conservação in situ

Abstract

The species Urena lobata L. adapts to different types of environments, such as floodplain and terra firme areas as well as tropical and subtropical climate conditions. It’s considered rustic and is well-suited for more extensive studies on the constitution of inorganic components in altered environments and how a species is affected by climate change. The aim of this work was to study the phenotypic diversity of U. lobata plants in two Amazonian environments, in an anthropogenic area of terra firme and floodplain, and to predict the distribution of the species in future scenarios resulting from climate change. In the first chapter of this thesis, the phenotypic diversity of the species was studied. Eight plants were sampled in an anthropized area of terra firme and eight from a floodplain and each plant studied were from rhizospheric soils, leaves and roots, totaling 24 per area. Analyses were performed using total reflection X-ray fluorescence (TXRF). The groups were segmented using the hierarchical distance means method (UPGMA), graphical dispersion was performed using the Principal Coordinate Analysis Method (PCA) and non-metric multidimensional scaling analysis. A TXRF analysis detected 16 inorganic elements in soil and plant tissues. These nutrients and elements are considered potentially toxic. Utilizing statistical analysis, we grouped the plants according to the type of area studied. U. lobata presented itself as a potential phytoremediator or bioindicator of trace elements present in the areas. In the second chapter, future projections were carried out in two RCP (Representative Concentration Pathways) scenarios: RCP 4.5 (average pessimistic) and RCP 8.5 (most pessimistic), in two time intervals (2020-2050 and 2051-2070). The Envelope Score algorithm best represents the species distribution. The mandatory model was used to verify the potential occurrence of U. lobata in the current and future periods in the six Brazilian biomes; Amazon, Cerrado, Caatinga, Atlantic Forest, Pantanal and Pampa. The results confirm that a species is rustic and has low vulnerability in RCP 4.5. However, there was a loss of favorable area due to RCP 8.5, with a tendency to establish populations in regions at higher altitude in the Southeast and South regions of the country. The findings showed the need for conservation of populations of the species in regions that are more sensitive to occurrence, to ensure the maintenance of genetic variability.