Solos hidromórficos do Triângulo Mineiro: controle edáfico de espécies nativas

Abstract

water saturation for an intermediate period or throughout the year. Such ecosystems are essential for maintaining biodiversity and water resources. Changes in the use and occupation of hydromorphic soils can affect the entire ecosystem due to their edaphic control and the presence of native species. This study aims to analyze the effect of hydromorphic soil attributes on the edaphic control of two wetland phytophysiognomies in the Triângulo Mineiro region (MG, Brazil). A total of 60 plots (10 m × 10 m) were established for the collection of structural vegetation data, as well as for soil sampling in each plot at a depth of 0 to 20 cm for chemical and physical analyses. Floristic similarity was calculated using the Jaccard index. To analyze the variability of species composition, the non-metric multidimensional scaling method (NMDS) was used. The importance value index (IVI) was calculated to verify the vegetation structure. Indicator species analysis (IndVal) was used to assess the strength of association between species abundance and frequencies and the six environments. Soil physical and chemical parameters were summarized using Principal Component Analysis (PCA). To assess a possible relationship between edaphic variables and species abundance, Canonical Correspondence Analysis (CCA) was used. A total of 817 individuals were sampled, distributed across 92 morphospecies, belonging to 58 genera and 40 families. The Jaccard index indicated greater floristic similarity among Gallery Forests, while NMDS analysis revealed significant variation in species composition between the Gallery Forest and Vereda environments (PERMANOVA: F7,13 = 3.93; p < 0.001). The Gallery Forest phytophysiognomy stood out as an eutrophic environment with higher base saturation, whereas Veredas showed higher organic matter (OM) content, clay levels, and potential acidity. Species in the Gallery Forest were grouped based on pH, Ca²⁺, and K⁺, while species in the Vereda were more influenced by OM, Na⁺, Al³⁺, and clay. The CCA analysis identified significant correlations between species abundance and edaphic variables, highlighting the importance of Na⁺, OM, and silt. It is concluded that the soil-vegetation relationship in the wetlands of the Triângulo Mineiro presents environmental and ecological heterogeneity among the studied areas, while also emphasizing the importance and fragility of these systems.