Updating Biodiversity Status and Changes in the Permanent Monitoring Stations of San Roque Metals Incorporated Mining Areas, Tubay, Agusan del Norte, Philippines

Abstract

Since 2015, biodiversity-related surveys have been conducted biennially in the San Roque Metals Incorporated (SRMI) mineral production areas in the Municipality of Tubay, Agusan del Norte, Philippines. The company established five permanent monitoring stations in the selected habitats to monitor biodiversity and species richness effectively. The present study assessed changes in the monitoring stations using a quadrat-transect method and compared the diversity and species richness of the previous sampling periods. The results of the floristic survey recorded 160 morpho-species of seed plants (angiosperms and gymnosperms), ferns, and their allies, with 52% comprising tree species. Over time, a significant increase in the number of species was observed at the monitoring stations; however, Shannon’s Diversity Index remained low (H'=2.3610; range 0.68-1.73) for all sites. The most dominant plant habits were trees, followed by ground-dwelling herbs, vines, and climbers. Paspalum conjugatum was the most dominant ground cover, occupying 22%, and other common grass species, such as Scleria scrobiculata, Dicranopteris linearis, and Imperata cylindrica, accounting for 19%, 14%, and 14%, respectively. Approximately 70% of the identified species were native, and 13.5% were endemic to the Philippines. Nine recorded species were listed on the Philippine Red List or the IUCN Red List of Threatened Species. Although it was found that the species richness of mining areas has slightly increased since the last floristic surveys, the study recommends considering the provisions for no-mine zones and genetic conservation areas for future mine restoration and rehabilitation activities.