Cebu Island Research Articles

Survey on children's dietary intake in poor areas of Cebu island, Philippines

Survey on children's dietary intake in poor areas of Cebu island, Philippines

Mangrove forest composition, diversity, and disturbances in Carcar City and Sibonga Municipality, Southern Cebu Island, Philippines

Abstract. Lillo EP, Malaki AB, Alcazar SMT, Chavez MLM, Rosales R, Tomol CJ, Pantinople EM, Redoblado BR, Margate MA, Diaz JL, Isabelo JL, Cagara BNR, Abrigana M, Mago JE, Cañarijo III DM, Sanchez IRG, Obando ME, Belañizo J, Beceril R, Carreon J, Diaz GGG, Gonzaga CFO, Davirao CR, Revillas MJS, Lim JM, Lillo EP. 2024. Mangrove forest composition, diversity, and disturbances in Carcar City and Sibonga Municipality, Southern Cebu Island, Philippines. Biodiversitas 25: 2035-2043. Mangrove forests are one of the world’s most vulnerable tropical ecosystems. The study assessed the mangrove forest composition, diversity, and disturbances in Sibonga Municipality and Carcar City, Cebu Island, Philippines, as a basis for its conservation planning. A transect line was established for a minimum length of 1000 m and a maximum of 2000 m (seaward, middleward, and landward), at an interval of 100 meters. A 10 × 10 m quadrant was established within the transect line at 250 m intervals resulted in a total of 108 plots. Disturbances and threats in two sampling sites were evaluated through direct field observations and interview, and analyzed using the Beynen and Townsend disturbance index. The study identified 22 true mangrove species categorized into 11 families and 14 genera with Excoecaria agallocha L., Sonneratia alba Sm., Rhizophora apiculata Blume, and Avicennia marina (Forssk.) Vierh dominating both sites. The endangered Pemphis acidula J.R.Forst. & G.Forst. was recorded in Sibonga. Aside from low diversity, both sites exhibited a high disturbance index due to illegal activities such as cutting, charcoal production, and land conversion. Such disturbances affects biodiversity and threatens coastal community. Urgent local government action is needed to preserve these ecosystems, emphasizing awareness and community involvement for long-term survival.

Assessing the taxonomic identity and distribution of endemic and critically endangered Cynometra cebuensis F. Seid. (Fabaceae) in Cebu Island, Philippines

Abstract. Lillo EP, Malaki AB, Alcazar SMT, Chavez MLM, Cañarijo III DM, Pantinople EM, Redoblado BR, Margate MA, Diaz JL, Flores KMC, Lillo JMP, Gonzaga CFO, Rosales R, Almirante A, Tomol CJ. 2023. Assessing the taxonomic identity and distribution of endemic and critically endangered Cynometra cebuensis F. Seid. (Fabaceae) in Cebu Island, Philippines. Biodiversitas 24: 4854-4861. Cynometra cebuensis F. Seid. is a newly discovered species and considered endemic to Cebu Island, Philippines. Yet, it faces extinction threats, making it a critically endangered species. Information on the taxonomical certainty and geographical ranges is important to facilitate its protection and conservation. Therefore, this study focuses on the identification and distribution of C. cebuensis in Cebu Island, Philippines. Field surveys were conducted across various Key Biodiversity Areas and the Cebu Central Protected Landscape, specifically the Tabunan forest, to ascertain the distribution of these species. The Leaf Architectural Working Group Manual was employed to meticulously describe leaf characteristics, supplemented by information from published literature. Contrary to previous assumptions that C. cebuensis F. Seid. exclusively inhabited the Tabunan forest within Cebu Central Protected Landscape, this study reveals its presence in multiple areas outside Tabunan. Notably, C. cebuensis F. Seid. displays several distinct characteristics that differentiate it from other congeners, encompassing leaf structure, shape, fruit dimensions, growth patterns, and a unique identification key. Given its confinement to Cebu Island, C. cebuensis F. Seid. is acknowledged as an endemic species. Accurate identification of this species assumes pivotal importance in steering effective conservation endeavors. However, its distribution is observed to be confined to a few remaining forested patches. This emphasizes the urgency of safeguarding the Key Biodiversity Areas within Cebu Island, Philippines, where the exclusive presence of C. cebuensis F. Seid. has been ascertained.

TYPHOON HAZARD ANALYSIS OF THE CEBU-CORDOVA LINK EXPRESSWAY ACROSS MACTAN CHANNEL

The Cebu-Cordova Link Expressway (CCLEX) is an inter-island bridge that links Cebu City to Mactan Island through the municipality of Cordova. The 8.9-km-long structure spans from the Cebu South Coastal Road (CSCR), crosses the Mactan Channel and Mactan Reef Flat, then connects to a causeway in Barangay Pilipog in Cordova. It is the longest and tallest bridge in the Philippines as of 2022. The channel is approximately 12-km-long strait bound to the northwest by Cebu Island and to the southeast by Mactan Island. Both ends of the channel are approximately 0.5 km wide. Adjacent to the southwest end of the channel is the Mactan Reef Flat. It is a 3,000-hectare expanse of mangroves, corals, and seagrass. CCLEX, with its local features, consisting of causeways, viaducts, pylons with pile foundations, piers, bridges, tidal inlets, and a toll plaza, is found to have affected the wave climate within the Mactan Channel and Mactan Reef Flat during extreme typhoons. This paper presents the analyses and synthesis of the effects of the CCLEX substructure on the extreme hazards of storm tide and typhoon waves of typhoons that tracked Mactan Channel.

Rural peoples’ perception, attitude, and engagement on invasive alien plants in Mount Manunggal, Cebu Island, Philippines

This research examines the perceptions of rural residents of Mount. Manunggal, Cebu Island, Philippines, on the impact of unintentionally introduced invasive alien plants, such as Mikania micrantha, Lantana camara, and Chromolaena odorata, on their livelihoods. Results suggest that their perception of the impact of each species on their livelihood varies based on criteria such as: (1) the length of time invasive alien plants have been established in the forest, and (2) the kind of household. In addition, a household study revealed that forest-adjacent homes have reacted to invasive alien plants as both victims and beneficiaries. Most of the surveyed 77 families are likely to adapt to the invaded environment because they have a history of interacting with invasive alien plants and regard them as wonderful sources of necessities if appropriately involved. In addition, the data demonstrated rural residents are eager to invest in the control and management of invasive alien plants provided the government provides standardized and adequate technical methods and skills. Without government and stakeholder assistance, decreasing the invasion is seen as impossible, and the acceptance of invasive alien plants as part of the rural ecology is foreseen as a predictable result.

EFFECT OF CONTEXTUALIZED LEARNING MODULES ON THE JOB APPLICATION SKILLS OF JOB SEEKERS

Employability is one of the strongest driving forces of an individual to strive for personal development and skills improvement continually. Among the job seekers of the municipality of Tuburan, on the island of Cebu, Philippines, 20 aspiring individuals were purposively chosen to undergo a training series using contextualized learning modules designed to respond to the required skills by identified prospective employers directly. Sets of pre-and post-tests were given before and after the conduct of the sessions to measure the effects of the designed modules on the job application skills of the respondents. After the training sessions, the respondents were asked to apply for jobs while being monitored by the team. The results demonstrated that using contextualized learning modules significantly enhanced respondents' abilities in terms of resume writing, interview preparation, and technical skills like using Microsoft Office and Google productivity tools, basic computer operations, and using the internet and managing emails. The researchers advise using the learning modules and maximizing their adaptability to the starting points of job seekers' knowledge.

Acanthochaetetes reitneri nov. sp. (Porifera: Demospongiae) from the Lower Cretaceous (upper Aptian–lower Albian) Tuburan Limestone of Cebu Island (Philippines) and its stratigraphic and palaeobiogeographic implications

Acanthochaetetes reitneri nov. sp. (Porifera: Demospongiae) from the Lower Cretaceous (upper Aptian–lower Albian) Tuburan Limestone of Cebu Island (Philippines) and its stratigraphic and palaeobiogeographic implications

Satellite-based monitoring of an open-pit mining site using Sentinel-1 advanced radar interferometry: A case study of the December 21, 2020, landslide in Toledo City, Philippines

Understanding the causal factors and mechanisms behind catastrophic landslides and debris flows is crucial for accurate forecasting and disaster risk reduction. Synthetic aperture radar (SAR) data and interferometric SAR (InSAR) technologies provide valuable information for early warning systems’ landslide and debris flow detection and monitoring strategies. This paper applied the Sentinel-1 Persistent Scatterer InSAR (PSInSAR) technique to detect and monitor precursory slope movements over the open-pit mining site in Toledo City, Cebu Island, in the Philippines. The results show that the slope showed instabilities between December 30, 2019, to December 12, 2020, before the actual failure on December 21, 2020. The landslide initiation zone moved with velocities exceeding –10 mm/yr and reaching –90 mm/yr. The topography and morphology of the mining site contributed to the cut slope instabilities. The mining operations and hydrometeorological conditions during the analysis period aggravated the situation, leading to the cut slope failure. Overall, with favorable slope geometry, surface characteristics, and SAR data availability, the Sentinel-1 PSInSAR technique can serve as a landslide early warning system tool and aid decision-making in an actively operating open-pit mine and other landscapes.

Saints of Resistance: Devotions in the Philippines under Early Spanish Rule by Christina H. Lee

Reviewed by: Saints of Resistance: Devotions in the Philippines under Early Spanish Rule by Christina H. Lee Florina H. Capistrano-Baker Saints of Resistance: Devotions in the Philippines under Early Spanish Rule. By Christina H. Lee. (Oxford: Oxford University Press,. 2021. Pp. xii, 216. $74.00. ISBN 978-0-190-91614-5.) A small statue of the Christ Child with a darkened face towers above the blurred images of devotees’ hands holding the divine image aloft. The main title (Saints of Resistance) in large white font against an orange background anchors the eyes as they travel below to the secondary title and author’s name. The evocative title and book jacket design entice the reader to explore the contents within. The book is organized in six chapters including the introduction (chapter 1) and conclusion [End Page 202] (chapter 6). Each of the four main chapters focuses on a particular Philippine devotion: Santo Niño de Cebu (chapter 2), Our Lady of Caysasay (chapter 3), Our Lady of the Rosary (chapter 4), and Our Lady of Antipolo (chapter 5). The font is reader-friendly, and the photographs, though black and white, are well chosen. The author, Christina Hyo-Jung Lee, is a professor in the Department of Spanish and Portuguese at Princeton University. Her work addresses cultural productions of Iberian Spain and the Spanish Pacific. Born in South Korea and raised in Argentina, she immediately engages the reader with her introductory statements: My first visit to the Philippines was laced with simultaneous feelings of eerie familiarity and strangeness. I encountered reverberations of my Hispanic and Asian upbringing wherever I went (p. 1). The introduction includes a useful review of studies on iconographic devotions in the Spanish world in general, and in Spanish colonial Philippines in particular. Lee’s transpacific background, native fluency in the Spanish language, and meticulous scholarship generate important new interpretations and insights into popular Philippine devotions heretofore unexplored. For example, her careful rereading of primary sources interrogates conflicting translations of sixteenth-century Portuguese explorer Ferdinand Magellan’s chronicler Antonio Pigafetta’s original account of their encounter with the ruler Humabon and his wife on the Philippine island of Cebu. An important point of contention is whether the image now venerated as the Santo Niño de Cebu is indeed the icon that Magellan had gifted Humabon’s wife in 1521 (pp. 19–21). Combining contemporary field research in Cebu with critical re-reading of early Spanish accounts, Lee calls attention to competing narratives where local inhabitants claim the statue as their own, all versions claiming that the Spanish usurped a pre-existing local devotion by snatching the image away. The next three chapters on Our Lady of Caysasay, Our Lady of the Rosary, and Our Lady of Antipolo similarly explore how foreign icons and narratives are purposely appropriated as autochthonous phenomena and subsumed into the corpus of Filipino culture. Closely reading primary sources, Lee points to mechanisms that transform the narrative of European images into counter-hegemonic narratives and strategies of resistance. Lee concludes with the general observation that the santos discussed “were widely embraced by their followers . . . because their devotions embedded narratives that memorialized their communities’ survival and resistance amid impossible situations” (p. 132). Lee’s intriguing interpretations and engaging writing style, free of jargon that often plagues academic writing, encourage the reader to read the entire book in one sitting; and to re-read and ponder the ideas presented anew. I have advocated in previous publications for scholarly dialogue between “cultural insiders” and “cultural outsiders” to de-colonize and move forward the discourse [End Page 203] on global history. In studying Spanish colonial Philippine iconographic devotions, Lee occupies a liminal space between cultural insider and outsider, creating an intellectual bridge for both to meet. This book is useful for students and scholars of cultural history, art history, religious studies, and material religion. It is a must read for scholars of the sixteenth-to-nineteenth-century Spanish colonial period in the Philippines. Florina H. Capistrano-Baker Ayala Museum Makati, Metro Manila, Philippines Copyright © 2023 The Catholic University of America Press ...

Population density and distribution of the Endangered Black Shama Kittacincla cebuensis

Summary The Endangered Black Shama Kittacincla cebuensis is endemic to the island of Cebu, Philippines. We surveyed 11 forest patches from February 2018 to March 2020 to determine current distribution, habitat requirements, and population density of the Black Shama. A total of 111 point count stations was surveyed resulting in 93 Black Shama detections. Using point count Distance sampling, the population density was estimated at 313 individuals/km2 for a total population of 11,839 individuals (9,160–15,415). The largest sub-population (10,470) was in Alcoy, followed by Argao (711), and Dalaguete (325). Our total population estimate and sub-population estimates were higher than the estimate of 6,650 individuals made by BirdLife International for the International Union for the Conservation of Nature. The species was found to survive in a variety of habitats in at least 20 localities covering roughly 37 km2 of karst forest. We did not encounter the bird in seven areas of its former range. Protection of the remaining forests of Cebu and the establishment of plantations of native tree species in between forest patches are crucial to the survival of the species.

The Lower Cretaceous Tuburan Limestone of Cebu Island, Philippines: Microfacies, micropalaeontology, biostratigraphy, and palaeogeographic perspectives

The occurrence of orbitolinid-bearing shallow water limestone blocks (Tuburan Limestone) incorporated into the volcanic series from Cebu Island, Central Philippines, has been known since the 1950's. Taxonomic studies including solid biostratigraphic data however are lacking or not substantiated. Herein we report the occurrence of Mesorbitolina texana (Roemer), transitional forms between M. texana and M. subconcava (Leymerie), Mesorbitolina birmanica (Sahni), Palaeodictyoconus actinostoma Arnaud-Vanneau & Schroeder, Neorbitolinopsis conica (Matsumaru), Paracoskinolina sp. and other benthic foraminifera (Akcaya, Praechrysalidina, Vercorsella) indicating a latest Aptian age. The previously accepted Late Albian age for the Tuburan Limestone based on Neorbitolinopsis conulus (Douvillé) is rejected herein and suggested as a misidentification with the recently revised Aptian - Lower Albian Neorbitolinopsis conica (Matsumaru). The general poverty of Lower Cretaceous dictyoconids in the Tuburan Limestone is interpreted as being caused by the lack of suitable extensive lagoonal facies that is generally typical for carbonate platforms of passive continental margins. The observed microfacies types instead refer to external platform margin settings with corals, stromatoporoids, sclerosponges (e.g., Acanthochaetetes), and planktic foraminifera. The recovered (micro) fauna from Cebu Island shows striking similarities to assemblages reported from Western and Mid-Pacific guyots but with indicated younger ages (up to the late Albian) based on data that - in our opinion - do not stand up to close scrutiny. Finally, a model is proposed interpreting the Tuburan Limestone from Cebu Island as remnants of a former carbonate cover of a guyot that originated as a volcanic island in the Western-Central Pacific, and later became incorporated into an accretionary wedge/mélange zone due to subduction-collisional processes.

Water Management Practices and Environmental Attitudes of Riparian Communities in Sapangdaku River, Cebu Island, Philippines

Understanding the social-ecological dynamics of freshwater ecosystem is critical for effective planning and sustainable use of the resource. The study aimed to determine the socio-demographic profile, anthropogenic activities, water utilization of the residents, and waste disposal practices along the Sapangdaku River. Here, we examined water utilization, waste disposal practices and their corresponding impact to health, and environmental attitudes of riverside dwellers (n=120) in Sapangdaku River by using a standardized social health and environmental attitudes survey, respectively. Results show that while river water is still largely used for bathing and backyard farming, its known function as (a) disposal area of human and animal waste, (b) quarry site for pebbles and sand and (c) laundry area significantly decreased in recent years. Responses revealed that occurrence of very common ailments such as cough, gastroenteric problems and skin problems are partly associated to poor river water quality. In terms of people’s environmental attitude, ecocentrism is both positively correlated to environmental movement activism (r=0.445, p=0.000) and human utilization of nature (r=-0.275, p=0.006), putting prime value on the sustainable use of river water that provides benefit to the community. Similarly, environmental movement activism and human utilization of nature (r=-0.327, p=0.001) indicates willingness to participate in environmental activities, hence supported by their decision not to use their environment unfavorably. These findings suggest that community’s concern for the river water resulted to increased participation in various strategies to better maximize the use of the river for various purposes. However, efficient management and restoration of river quality require a holistic view of the problem.

Elucidating the surface macroplastic load, types and distribution in mangrove areas around Cebu Island, Philippines and its policy implications

The Philippines is identified as one of the major marine plastic litter polluters in the world with a discharge of approximately 0.75 million tons of marine plastic debris per year. However, the extent of the plastic problem is yet to be defined systematically because of limited research. Thus, this study aims to quantify plastic litter occurrence in mangrove areas as they function as sinks for plastic litter due to their inherent nature of trapping plastics. To define the extent of marine plastic pollution on an island scale, mangrove areas in 14 municipalities around Cebu Island were sampled, with 3 to 9 transects in each site depending on the length of coastline covered by mangroves. Sampling and characterization of both plastics and the mangrove ecosystem was performed in three locations along the transect – landward, middle, and seaward. A total of 4501 plastic items were sampled throughout the study sites with an average of 1.29 ± 0.67 items/m2 (18.07 ± 8.79 g/m2). The average distribution of plastic loads were 2.68 ± 1.9 items/m2 (38.52 ± 25.35 g/m2), 0.27 ± 0.10 items/m2 (6.65 ± 4.67 g/m2), and 0.94 ± 0.61 items/m2 (9.04 ± 4.28 g/m2) for the landward, middle, and seaward locations, respectively. The most frequent plastic types found were i) packaging, ii) plastic bags and iii) plastic fragments. The plastic loads and types suggest that most plastic wastes trapped in mangroves come from the nearby communities. Fishing-related plastics originated from the sea and were transported across the mangrove breadth. The findings confirm that mangroves are major traps of plastic litter that might adversely affect the marine ecosystem. The study underscores the urgent need for waste mitigation measures, including education, community engagement, infrastructure, technological solutions and supporting policies.

High-resolution peak ground acceleration modeling using geographic information systems: A case study of the potentially active Central Cebu Fault System, Philippines

The heavily populated Cebu Island is cut by the Central Cebu Fault System (CCFS). While the CCFS has not produced any MW > 5.0 earthquakes in the past century, recent strong earthquakes in the adjacent islands have brought attention to the seismic hazards in the region. Fault properties such as strike, dip, slip direction, and surface trace length were determined based on literature review, fieldwork, and analysis of geomorphic features. Empirical relations were utilized to estimate down-dip width and magnitude. The gathered data were used to create a three-dimensional model of the four major faults in the CCFS: Balamban Fault, Central Highland Fault, Uling-Masaba Fault, and Lutac-Jaclupan Fault. The 3D model was used to generate peak ground acceleration maps of central Cebu, should an earthquake occur along any of the major faults. Site corrections were made based on the seismic velocity of the upper 30 m of the subsurface. The major faults are estimated to be capable of generating MW 6.4 to 7.1 earthquakes. Worst-case scenarios in densely populated areas show 0.40 to 0.70 g of PGA, suggesting the potential for severe damage in central Cebu. We explored the advantages of using raster mathematics in a GIS platform for calculating and presenting ground motion. These advantages include rapid calculations for tens of millions of points, reducing the effects of interpolation artifacts in final map products. This study emphasizes the importance of detailed structural, geological, and geomorphological data in modeling seismic hazards. Further investigations on the seismogenesis of the CCFS segments are recommended.

Diversity and conservation status of avifauna in Mount Lantoy Key Biodiversity Areas (KBA) in Cebu Island, Philippines

Abstract. Malaki ABB, Alcazar SMT, LILLO EP, Rosales RC, Redoblado BR, DIAZ JL. 2021. Diversity and conservation status of avifauna in Mount Lantoy Key Biodiversity Areas (KBA) in Cebu Island, Philippines. Biodiversitas 23: 671-678. A study on the bird community in Mount (Mt.) Lantoy Key Biodiversity Areas (KBA) was carried out to determine its diversity and conservation status to conserve, protect, and rehabilitate forest habitat within the KBA. The study was conducted across three sampling sites. By using the transect, point count, and mist nets, we found 1,340 individuals belonging to 31 orders, 32 families, and 44 species within the study sites. There were five dominant bird species, i.e., Hypsipetes philippinus (J.R.Forster, 1795), Phapitreron leucotis (Temminck, 1823), Psilopogon haemacephalus (P.L.S.Müller, 1776), Nectarinia jugularis (Linnaeus, 1766), and the endangered Kittacincla cebuensis (Steere, 1890). We also found rare bird species within the study site, such as Haliastur indus (Boddaert, 1783), Geopelia striata (Linnaeus, 1766), Monticola solitarius (Linnaeus, 1758), Oriolus chinensis (Linnaeus, 1766), Dendrocopos maculatus (Scopoli, 1786), Pycnonotus goiavier (Scopoli, 1786), and Rallina eurizonoides (Lafresnaye, 1845). We also found six Philippine endemics, including K. cebuensis, Ninox rumseyi (Rasmussen et al. 2012), H. philippinus, D. maculatus, Loriculus philippensis (Statius Muller, 1776), and Caprimulgus manillensis (Walden, 1875). Based on the IUCN Red List of Threatened Species, two species are Endangered, and 42 species are Least Concern (LC). Using the "Checklist of the Birds of the Philippines," we found two species are Endangered, two species are Near Threatened, and 40 species are LC. The diversity of birds in Mt. Lantoy KBA was moderate. We considered that this KBA is highly exposed to various forest or habitat disturbances such as land-use conversion, charcoal making, firewood gathering, slash-and-burn method of cultivation, and infrastructure development. There is a need to strictly implement the policies governing the utilization of forest resources to augment the diversity of the study site.

Evaluating mitigation strategies for urban heat island in Mandaue City using ENVI-met

Mandaue is a crucial city in Cebu island, Philippines as it links other large metropolises and is highly industrialized. The occurrence of urban heat island (UHI) in Mandaue was already confirmed by a previous study. In this paper, we aim to determine how UHI in Mandaue could be improved by mitigations including increasing vegetation, adding open spaces, employing green roofs and/or a combination thereof. ENVI-met software was utilized to simulate two study sites: M. C. Briones street and the planned urban development (PUD). To reduce computing load, M. C. Briones street was further divided into 2 subareas and PUD into 4 subareas. Results of the simulation indicate that addition of more urban spaces and trees could decrease air temperature by 0.2 ​°C on average while green roof could decrease air temperature by an average range of 0.2 ​°C–0.4 ​°C. When a combination of trees, grasses and green roof is used, air temperature could be decreased by an average range of 0.1 ​°C–0.3 ​°C. Despite these mitigations, thermal comfort index in Mandaue would still be greater than 26 ​°C which means that majority of the people would feel uncomfortable. On the other hand, addition of more urban spaces and trees could decrease surface temperature by an average range of 0.5 ​°C–0.8 ​°C while conversion of building roofs into green roofs would have no effect. When a combination of vegetation and green roof is employed, surface temperature could be decreased by an average range of 0.4 ​°C–1.1 ​°C.

Inventory of native and mother trees in Key Biodiversity Areas of Cebu Island, Philippines for species selection in local reforestation programs

Abstract. Lillo EP, Malaki AB, Alcazar SMT, Rosales R, Redoblado BR, Diaz JLB, Pantinople EM, Buot Jr. IE. 2021. Inventory of native and mother trees in Key Biodiversity Areas of Cebu Island, Philippines for species selection in local reforestation programs. Biodiversitas 22: 4740-4749. Forest restoration is the counterforce of deforestation and forest degradation. Yet, despite promoting natural recovery after forest harvest, afforestation and reforestation efforts, tropical forest ecosystems still experience a poor ratio of forest loss to forest gain. The study assessed the native tree species and potential mother trees in different Cebu Island Key Biodiversity Areas (KBAs) as well as their distribution and habitat preferences which can be used in local reforestation programs. A vegetation survey was conducted in three KBAs in Cebu Island, namely Nug-as forest, Mount Lantoy and Mount Capayas to inventory all native species. Assessment based on the phenotypic characteristics of adult trees was also conducted for indicating mother trees. This study in Cebu Island KBAs recorded a total of 292 species, categorized into 125 families and 203 genera, which can be classified into native trees (210), vines and lianas (18), shrub (37), and herbs (27). Out of the 292 species, 214 were recorded in Nug-as forest, 172 in Mount Lantoy, and 145 in Mount Capayas. Of the 210 native tree species, Nug-as forest had 145 species, Mount Lantoy 131 species, and Mount Capayas 109 species. A total of 241 mother trees were identified in the three KBAs, corresponding to 77 species in which Nug-as forest had 143 trees correspond to 52 species, Mount Lantoy had 68 trees correspond to 29 species, and Mount Capayas had 31 trees correspond to 6 species. Such native tree species are recommended for reforestation programs as planting materials that could reduce the risks of failure due to its high adaptability to the environment.

Moving Up the Electrification Ladder in Off-Grid Settlements with Rooftop Solar Microgrids

The multi-tier framework (MTF) of electricity access defines a continuum of electrification from tier 0, where access is inexistent or very limited, to tier 5 where access is of grid quality. Transitioning households from lower to higher tiers unlocks the potential in meeting more of their energy needs. This study investigates the transition towards higher tier electricity access on Gilutongan Island, an off-grid island of Cebu, Philippines, which is also an informal settlement community with no open land available for a centralized solar PV system. The solar PV potential of suitable rooftops on the island was determined using satellite imagery, ground measurements, and computation. The electricity demand of a cluster of 11 households was examined in detail; these households, situated near two suitable rooftops, were connected to an installed 7.92 kWp solar PV-based microgrid. Results show that the households moved up from lower to higher tier levels in all MTF attributes except for affordability. Nevertheless, the cost of a standard electricity consumption package of 1 kWh/day dropped from 18% of the average household income to 6%. Moving up on the electrification ladder to higher tier electricity access in off-grid areas is attainable with households clustered as a microgrid using rooftop solar PV. Affordability remains to be the biggest challenge that needs to be addressed.

Mapping Hotspots of Human Impact on Native Dendroflora Biodiversity in Cebu Island, Philippines

The continuing pressure on the natural environment exerted by human activities such as land conversion has been threatening to drive tens of thousands of species to extinction globally for decades. Species conservation requires identifying species ranges impacted by threats, which helps predict localized extirpations and potential extinctions. This paper assessed the human pressures that threaten the local biodiversity in Cebu Island, Philippines, to help prioritize actions to manage and mitigate human impacts on local biodiversity. Hotspots, where modeled dendroflora species richness is compromised, were identified through a spatial overlay of pre-defined high-resolution human pressure variables. A notable observation was that the largest and only protected KBA – the Central Cebu Protected Landscape (CCPL) – had the highest percentage occurrence of medium to high threats within its boundaries, which could be attributed to its proximity to highly populated municipalities and cities. More importantly, possible areas of refuge for key species were identified. These areas could be appropriated as local restoration sites by the local government units of Mt. Lanaya and Nugas forest in the south of Cebu since these KBAs had high dendroflora richness but with less occurrence of high threats. The resulting maps could also be used as important references for targeted conservation management programs to help mitigate the threats that are driving local species to their decline and for preemptive planning of local and national conservation agenda.

Genesis, geochemical evolution and metallogenic implications of magnetite: Perspective from the giant Cretaceous Atlas porphyry Cu–Au deposit (Cebu, Philippines)

The Atlas porphyry Cu–Au deposit (PCD) in central Cebu Island (Philippines) has a proven ore reserve of 1420 Mt @ 0.45% Cu, 0.24 g/t Au, 0.018 g/t Mo, and 1.8 g/t Ag. The PCD is characterized by four generations (Mag1 to Mag4) of magnetite, a mineral that can record the chemical evolution of the magmatic-hydrothermal system. The magmatic Mag1 is characterized by being euhedral with ilmenite lamellae formed by the oxy-exsolution process. The well-developed microporosity and 120° triple junction suggest that Mag2 has been modified by recrystallization or dissolution-reprecipitation process. The Mag3 (from the early-ore Stage I) is well-porous with almost no oxy-exsolution ilmenite lamellae. The Mag4 is from the late-ore Stage II in which the Mag4a has distinctive zoning formed by massive cavities, whereas the Mag4b has only a few pores. LA-ICP-MS trace element (esp. Ti and V) compositions indicate that the formation temperatures decrease from Mag1a to Mag3, then increase from Mag3 to Mag4a, and eventually decrease from Mag4a to Mag4b. On the contrary, oxygen fugacity (fO2) decreases from Mag1a to Mag3 but increases from Mag3 to Mag4, suggesting two magmatic-hydrothermal pulses driven by the Lutopan porphyry intrusion at Atlas. This is consistent with the development of two mineralization styles at Atlas, i.e., high fO2 magnetite mineralization and the subsequent giant Atlas porphyry Cu–Au mineralization.