The mining tenements of Zambales house several heavy metal-tolerant species, many of which are native to the country. Considering their uniqueness, natural distribution, and the species’ ability to restore vegetation and conserve biodiversity, the College of Forestry and Natural Resources of the University of the Philippines in Los Baños (UPLB-CFNR) has teamed up with the Foreign Assisted and Special Projects Service of the Department of Environment and Natural Resources (DENR-FASPS), Zambales Diversified Metals Corporation (ZDMC), and local government units (LGUs) for a joint research and extension (R&E) effort aimed at undertaking an extensive geobotanical survey to document, catalog, collect germplasm, and conserve metallophytes.
Metallophytes are species of plants with the ability to thrive on soils with high concentrations of heavy metals, which other typical forest species find toxic. Through natural selection, these species are able to endure harsh environments by exhibiting various adaptive tolerance mechanisms. The production of polypeptides such as metallothioneins and phytochelatins allows the plants to survive, grow, and reproduce, even under metalliferous soil conditions. In some parts of the globe, metallophytes are commonly utilized for various technological applications, such as phytoremediation, phytostabilization, and phytoextraction.
In the study conducted, approximately one hectare of mined-out plot was planted with various metallophyte seedlings to serve as a potential restoration model. Findings showed the diversity and richness of metallophytes in the mined-out areas of Zambales, which harbored 72 indigenous species. Calendar of flowering and fruiting seasons, tolerance of the said species to acid, fire, and open grasslands, alongside seed germination and nursery cultivation technologies, were studied and documented.
The R&E study further revealed the great potential of metallophytes to uniquely address biodiversity conservation issues. Naturally adapted to metalliferous soils, these species do not only reforest stripped lands, but also restore ecological relationships, processes and integrity. (UPLB-CFNR/ John Dave Pilapil)