Assessment of a riparian forest by applying the forest quality index (QBR) for its adaptation in tropical areas of Mexico

The QBR index makes it possible the assessment of the quality of riparian forests. Therefore, QBR index was determined and correlated with attributes of vegetation and natural regeneration in five sites of the Tacotalpa River, Tabasco, Mexico: Tapijulapa, Arroyo Chispa, Nuevo Madero, Mexiquito, and Oxolotán. At each site, ten transects of 10 x 100 m sides, 20 squares of 10 × 10 m for vegetation sampling with DBH ≥ 1 cm and, 20 squares of 1 x 1 m for characterizing the natural regeneration. The values of QBR, structure, and diversity, were compared using a single factor ANOVA. In addition, a principal component analysis was performed between the QBR Index with vegetation variables. The QBR index ranged from 48.40 % and 91.10 %. Sites Mexiquito and Oxolotán showed good and very good quality (79.40 % and 91.10 %), with significant differences with Tapijulapa and Arroyo Chispa of acceptable and poor quality (56.60 % and 48.40 % respectively), but Nuevo Madero, of acceptable condition (67.90 %), did not show differences with Tapijulapa and Mexiquito, except Arroyo Chispa and Oxolotán. The QBR values were positively correlated with the richness and diversity of plants species, showing a tendency to improve in Tapijulapa together with Nuevo Madero, Mexiquito and Oxolotán. These values strengthen the hypothesis that ecological attributes provide greater reliability in the scores of the quality of riparian vegetation in tropical rivers.