Diversity of Mangrove Species and Environmental Management Practices in Sta. Cruz, Davao del Sur, the Philippines

Mangroves are regarded as one of the most productive, biologically complex, and considered the most significant element of the coastal ecosystem. Assessment of mangroves is essential to have sufficient data on the diversity of species to ensure ongoing conservation efforts to support effective management of the environment and resources. This research examined the mangrove species in Sta. Cruz, Davao del Sur, the Philippines, by establishing eight plots in four barangays and identifying environmental management practices through personal communications with the barangay officials of the respective covered barangays and the leaders of non-government organizations for mangrove conservation. The results of the assessment yielded 20 species from nine families, with the family Rhizophoraceae as the most represented with seven species. Two species, namely Avicennia rumphiana Hallier f. and Aegiceras floridum Roem. & Schult., were categorized as vulnerable and near threatened, respectively. The diversity indices of the four barangays in Sta. Cruz, Davao del Sur, revealed that Brgy. Tuban has the highest evenness index (E = 0.810) and Shannon-Weiner diversity index (H’ = 1.913), with the lowest dominance value (D = 0.180) indicating a good distribution and very few species dominating the area. Conversely, Brgy. Astorga showed the lowest evenness index (E = 0.372) and lowest Shannon-Weiner diversity index (H’ = 1.201). It recorded the highest dominance value of (D = 0.486), which implies a poor and uneven distribution of species and some species dominating the area. Identified management practices and conservation efforts include ordinances passed for the protection of fish sanctuary and mangrove forests, designating personnel for monitoring, giving incentives to those who catch people who are illegally cutting mangroves, partnerships for tree planting, adopt-a-tree initiatives, and assigning areas to divide the ocean to conserve mangrove areas.