Rapid Assessment of Plant Diversity in Ultramafic Soil Environments in Zambales and Surigao del Norte, Philippines

Abstract

This study covers the vegetation composition and diversity in two heavy metal sites with distinct climatic and edaphic environments in the Philippines, Zambales, and Surigao del Norte in the northern and southern regions, respectively, Tree density and basal area were higher in Zambales than in Surigao del Norte. Species diversity, however, was higher in Surigao del Norte site (H’=1.1071) than in Zambales, which may be attributed to high water and nutrient availability and unique geologic formations. Soil properties also varied, with higher organic matter concentration in Surigao del Norte. Twenty-one out of 35 taxonomic families in both sites were common in serpentine soils. Nine families were recorded to have a large number of individuals on both sites. A total of 11 species were known metallophytes of which four are Ni hyperaccumulators and seven are endemic to both sites. These Ni hyperaccumulators have a high potential for phytoremediation, phytostabilization, and rhizofiltration. However, due to the scarce information on Ni hyperaccumulators, conservation statuses of most of them are unknown. Agricultural interference, site destruction and excessive mining are some of the factors contributing to the diminishing fate of metallophytes. Thus, it calls for its prioritization in biodiversity conservation. Keywords: Plant diversity, ultramafic, nickel hyperaccumulators