The metallophytes in the ultramafic soil of mt. Kiamo in Malaybalay, Bukidnon, Philippines
By: Lowell G. Aribal, Rico A. Marin, Neil Antoni P. Miras
Key Words: Mt. Kiamo, Hyperaccumulator, Ultramafic soil, Mindanao, Metallophytes.
J. Bio. Env. Sci. 8(4), 142-150, April 2016.
Forests over ultramafic soils are considered rarest. Ultramafic soils contain high concentrations of metal elements. Species colonizing such ecosystem are termed metallophytes because these are able to accumulate heavy metals and grow normally without exhibiting phytotoxicity. In determining the metallophytes species, ten 20x20m sampling plots were established within the forest vegetation of Mt. Kiamo. All plants within the plots with ≥5 cm diameter at breast height (dbh) were identified, measured and recorded. Samples of roots and shoots of the most dominant species determined through quantitative analyses were collected and analysed to determine the hyperaccumulation potentials. Seven plant species with highest species importance value were identified consisting of Madhuca sp., Elaeocarpus merritii Merr., Falcatifolium gruezoi de Laub., Scaevola micrantha C.Presl., Calophyllum soulattrii Burm.f., Polyosma integrifolia Blume, and Agathis philippinensis Warb. Majority of the species accumulated extremely high varying levels of Fe, Mn and Cr while only S. micrantha could not be classified as Mn-hyperaccumulator based on shoot-root quotient. Both F. gruezoi and P. integrifolia are Ni-hypertolerant while F. gruezoi and A. philippinensis are Cu-hyperaccumulator. With the hyperaccumulation and hypertolerance exhibited by these species, we suggest to tests these plants under controlled condition to further verify if such characteristic is inherent to the taxon.