Álvarez Fajardo, Frayvel S.

Profile Picture

Filters

20251
Reset filters

Settings

Citations

Publication Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    PublicationRestricted
    El rol de los suelos serpentinos en la formación de bosques novedosos en Puerto Rico
    (2025-12-17) Álvarez Fajardo, Frayvel S.; Abelleira Martínez, Oscar J.; College of Agricultural Sciences; Sánchez de León, Yaniria; Pérez Alegría, Luis; Lugo, Ariel E.; Department of Agro-Environmental Sciences; González Cruz, Michael
    Little is known about ecological succession on tropical serpentine soils and how introduced species adapt to these extreme conditions. This study, conducted across 65.7 ha at Cerro Las Mesas, Mayagüez, evaluated the structure and composition of historical and novel forests growing on serpentine outcrops. Thirty plots were sampled to estimate tree density, height, and aboveground biomass, using analysis of variance and non-metric multidimensional scaling (NMS) to determine differences between forest types. Results showed significant structural contrasts: novel forests exhibited greater structural development, averaging 13.1 m in height and 172.8 Mg/ha in biomass, compared to 9.8 m and 50.6 Mg/ha in historical forests. In contrast, historical forests exhibited a higher density of small trees (3892 vs. 2217 trees/ha). These differences in structure and composition were strongly linked to soil chemistry; while historical forests were associated with high heavy metal concentrations, novel forests predominated in soils with greater nitrate and sulfate availability. These findings suggest that serpentine exerts a determinant environmental filter: nickel toxicity in historical forests excludes non-adapted introduced species. Conversely, in novel forests, more favorable edaphic conditions allow for the success of introduced species with acquisitive strategies, facilitating greater height and biomass development. Additionally, 20 functional traits, including leaf morphology and nutrient and metal concentrations, were analyzed in dominant species to determine community assembly mechanisms. Using NMS ordination and functional diversity indices (FRic, FEve, FDiv, FDis), it was found that historical forests exhibit low functional dispersion, indicating environmental filtering that favors convergence toward conservative strategies. The determinant traits that functionally differentiated the communities were leaf dry weight and leaf calcium concentration, evidencing that tolerance to edaphic stress is the primary axis of differentiation. In conclusion, historical forests showed lower functional diversity and conservative strategies, confirming that the environmental filter intensifies in zones with greater toxic potential. This evidences greater endemism in areas where the serpentine syndrome is most intense. In these sites, ecological succession depends on strict niche differentiation and a diversification of strategies to tolerate edaphic stress.