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Leyte Sab-A Basin peatland (LSBP) is the second largest peatland in the Philippines and comprises 3,088 ha (31 km²). The study estimated the C storage and carbon sequestration capacity of the peatland's four (4) ecotypes, namely, swamp forest (SF), marshland (ML), agroforestry (AF), and agricultural land (AL) using allometric equations. SF rendered the highest downed wood C-stocks followed by AL and AF. For the litter C-stocks, AF rendered the highest, followed by SF, ML, and AL. SF rendered the highest root C-stocks and CO2 sequestered, followed by AL and AF. C% is highest in ML with values ranging from 32-43 C% across the soil peat depth, while SF ranges from 29-34 C%, and AL and AF both with 19-37 C%. The LSBP stores 36.6 Tg of C and 134.5 Tg of CO2 sequestered. This C storage amount can represent 0.04% of tropical peat carbon. [ABSTRACT FROM AUTHOR]

Geohazards are often present in highly populated areas. Dynamic changes in population exposure to geohazards have resulted from shifting population numbers, spatial dispersion, and mobility. In addition, the changing vulnerability distribution of the population is a crucial consideration when establishing an effective evacuation strategy. Therefore, exploring the link between geohazards and population exposure is vital to avert disasters. This paper reviewed geohazards around the world based on a dynamic population approach. It identifies and synthesizes evidence of links between certain parts of the dynamic population and geohazard risk management. The major search engine in this investigation was Google Scholar. "Geohazards", "dynamic population", and keywords related to geohazards like landslides, floods, drought, earthquake, and tsunami were used, followed by terms related to dynamic population. The review shows that geohazards based on a dynamic population approach include socioeconomic status; gender and gender relations; migration, residency, and mobility; education and knowledge; and religions and beliefs. Understanding those elements is essential to managing geohazard risks because it can assist the government in its financial commitment and allocation in the event of a disaster, constructing effective policies and adaptation plans, and including communities in managing geohazard risks. [ABSTRACT FROM AUTHOR]

Laguna de Bay, the largest and nationally significant freshwater lake ecosystem in the Philippines, has been increasingly subjected to anthropogenic pressures over the years. Domestic, agricultural, and industrial activities in the surrounding areas have contributed directly and indirectly to the deterioration of the lake's overall ecological health and integrity. This study assessed the chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), lead (Pb), and cadmium (Cd) contamination in Asiatic clam, Corbicula fluminea, using quadrupole inductively coupled plasma–mass spectrometry. Estimated daily consumption of Asiatic clam was determined through a social survey. The data from analytical analysis and social surveys were utilized to calculate the target hazard quotient (THQ) to determine the potential health risks of consuming heavy metal–enriched clams to fishing households. Results from the Knowledge, Attitude, and Practices (KAP) survey indicated that the majority of the respondents have an acceptable level of knowledge on the hazards posed by the intake of contaminated clams but disapproved the banning of its collection and consumption. Sampled households with high consumption rates in all municipalities except Victoria were also found to be exposed to imminent health risk due to the high toxicity level of As based on their THQ values. Overall, one-third of the fishing households exposed to elevated health risk based on their total target hazard quotient (TTHQ) values already warrant a concern. The potential human health risks validate the worsening condition of Laguna de Bay. Integrative and holistic management of the lake through collaborative efforts of various stakeholders and institutions is necessary, to restore the health of the ecosystem and safeguard the health of the public. [ABSTRACT FROM AUTHOR]

The Zambales Ophiolite Complex (ZOC) in the western portion of Luzon Island, Philippines represents a typical exposure of an emplaced crust-upper mantle section of an ancient lithosphere. The ZOC is divided into the Acoje and Coto Blocks based on petrological, geochemical and age disparities, thus implying diverse and complex origins for the archipelago's lithospheric sources. We used gravity and magnetic data to reveal differences in the subsurface characteristics of the two ophiolite blocks for the first time. Low Bouguer gravity (<135 mGal) and magnetic (<69 nT) anomalies characterize the ophiolitic units in the Acoje Block whereas high Bouguer gravity (>150 mGal) and magnetic (>110 nT) anomalies typify the Coto Block. Such contrasting signatures further extend at greater depths which reflect the disparities in the crustal density, the basement structure, and the depth to Moho. Petrophysical characteristics such as density, magnetic susceptibility and natural remanent magnetization (NRM) intensities correlate well with the interpreted Bouguer gravity and magnetic anomalies. Densities of gabbros and peridotites from the Acoje and Coto Blocks reveal mean values ranging from 2640 to 2810 kg m-3 and 2570 to 2690 kg m-3, respectively. Magnetic susceptibility (>4.43 × 10-3 SI) and NRM (>0.69 A m-1) data are also generally higher over the Coto Block. Both Bouguer gravity and magnetic anomaly maps reveal a prominent steep gradient that potentially marks the structural contact between Acoje and Coto Blocks. We further infer that the steep anomaly gradient validates the presence of the Lawis Fault Zone which separates the two ophiolite blocks in the Masinloc Massif. Recent field evidence from rock exposures in Coto reveals both right lateral and vertical displacements along the fault zone. [ABSTRACT FROM AUTHOR]