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Botanical exploration on ultramafic sites in Palawan, Surigao and Zambales has resulted in the discovery of a new hypernickelophore species (nickel (Ni) concentration >1%) of Phyllanthus (Phyllanthaceae). This paper reports in detail the Ni uptake of populations of P. erythrotrichus in Candelaria, Masinloc and Santa Cruz, Zambales, and confirms the status of P. securinegoides in Taganito, Surigao del Norte, which had been analysed only through herbarium specimens, and these were compared with a known hypernickelophore, P. balgooyi, which was collected in Narra and Puerto Princesa, Palawan. Nickel content of the dried leaves, stems and root tissues was quantified using atomic absorption spectrophotometer. P. erythrotrichus and P. securinegoides both had more than 10 000 µg g–1 Ni in the leaves, whereas the roots had 1195 µg g–1 and 4636 µg g–1. P. balgooyi accumulated 6319 µg g–1 of Ni in the leaves, whereas the roots had a higher Ni concentration of up to 8116 µg g–1, respectively. All three species had values of translocation factor and enrichment factor of >1.0, implying that all species have great potential in phytoremediation, specifically, phytoextraction of Ni. These three species of Phyllanthus are prominent in ultramafic scrub communities and, hence, should be used in ecological restoration of mined-out Ni lateritic areas. The implications of the unique adaptation of these species are also discussed in relation to a conservation strategy for their natural populations.

The use of three freshwater microalgal culturesChlorella sorokiniana, Anabaena laxa, and Hapalosiphon welwitschii-for sorption of copper(II) from synthetic Cu (II) solutions and Marinduque, Philippines, wastewater was studied. The optimum amount of biomass for the three species was 0.025 g dry weight. The optimum contact time for both C. sorokiniana and A. laxa was 1 h, whereas that of H. welwitschii was 30 min. All three species exhibited maximum Cu(II) sorption at pH 4.0-6.0. The Langmuir adsorption isotherm was the best fit model for the three species. The three cultures were found to be effective biosorbents when used in synthetic wastewaters of low concentration (10-30 ppm). Maximum Cu(II) reductions obtained were 88.2, 88.6, and 91.7% for the C. sorokiniana, A. laxa, and H. welwitschii cultures, respectively. C. sorokiniana, A. laxa, and H. welwitschii removed 5.70, 11.16, and 7.15% of Cu(II), respectively, when applied to wastewater taken from Consolidated Mines Inc. (CMI) containing around 150 ppm Cu(II). C. sorokiniana and A. laxa, in combination, exhibited 14.05% Cu(II) removal from CMI wastewater. Desorption with 0.11 M HCl effected 73.20, 64.54, and 70.85% removal of Cu(II) from the surfaces of C. sorokiniana, A. laxa, and H. welwitschii, respectively. SEM-EDS spectra of the three species confirmed the presence of Cu(II) on their surfaces.

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Background. Mine waste from abandoned mining sites can cause environmental degradation and ecological imbalance to receiving water bodies. Heavy metal pollution affects local communities and may pose health risks to the general public. An abandoned mining facility in Marinduque, Philippines, situated on the of Mogpog River, continuously deposits mine wastes, which may affect the river and the health of local communities. Objectives. The aim of the present study was to examine the presence and extent of heavy metal contamination from mine wastes in the aquatic ecosystem of the Mogpog River by determining the level of heavy metal concentration in the water, sediments and biota. Methods. Four sampling sites were monitored for heavy metals (copper (Cu), arsenic (As), chromium (Cr) and sulfur (S)) pollution. Several analyses were conducted to determine the heavy metals present in the water, sediment and biota. Atomic absorption spectrophotometry was used for the analysis of Cu concentrations in water. X-ray fluorescence was used for the analysis of total heavy metals in the sediments and biota. Results. An inverse relationship with water and sediment from upstream to downstream of the river were observed. This trend shows deposition of Cu in the sediments as factored by pH. Flora gathered from the riverbanks recorded concentrations of Cu in their leaves and fruits. Conclusions. It has been difficult for the Mogpog River to regain water quality after years of mine waste deposition. Acid mine drainage occurred upstream of the river which affects the speciation of heavy metals. The potential risk of heavy metal exposure to local communities was observed due to the communities' river utilization. Participant Consent. Obtained Ethics Approval. The Office of Vice Chancellor for Research and Extension of University of the Philippines Los Baños approved the study Competing Interests. The authors declare no competing financial interests.