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Airborne ultrafine particles in a Pacific Island country: Characteristics, sources and implications for human exposure
2017
Isley, C.F. | Nelson, P.F. | Taylor, M.P. | Mazaheri, M. | Morawska, L. | Atanacio, A.J. | Stelcer, E. | Cohen, D.D. | Morrison, Anthony L.
The Pacific Islands carry a perception of having clean air, yet emissions from transport and burning activities are of concern in regard to air quality and health. Ultrafine particle number concentrations (PNCs), one of the best metrics to demonstrate combustion emissions, have not been measured either in Suva or elsewhere in the Islands. This work provides insight into PNC variation across Suva and its relationship with particle mass (PM) concentration and composition. Measurements over a short monitoring campaign provide a vignette of conditions in Suva. Ambient PNCs were monitored for 8 day at a fixed location, and mobile PNC sampling for two days. These were compared with PM concentration (TSP, PM10, PM2.5, PM1) and are discussed in relation to black carbon (BC) content and PM2.5 sources, determined from elemental concentrations; for the October 2015 period and longer-term data. Whilst Suva City PM levels remained fairly low, PM2.5 = 10–12 μg m⁻³, mean PNC (1.64 ± 0.02 × 10⁴ cm⁻³) was high compared to global data. PNCs were greater during mobile sampling, with means of 10.3 ± 1.4 × 10⁴ cm⁻³ and 3.51 ± 0.07 × 10⁴ cm⁻³ when travelling by bus and taxi, respectively. Emissions from road vehicles, shipping, diesel and open burning were identified as PM sources for the October 2015 period. Transport related ultrafine particle emissions had a significant impact on microscale ambient concentrations, with PNCs near roads being 1.5 to 2 times higher than nearby outdoor locations and peak PNCs occurring during peak traffic times. Further data, particularly on transport and wet-season exposures, are required to confirm results. Understanding PNC in Suva will assist in formulating effective air emissions control strategies, potentially reducing population exposure across the Islands and in developing countries with similar emission characteristics.Suva's PNC was high in comparison to global data; high exposures were related to transport and combustion emissions, which were also identified as significant PM2.5 sources.
Afficher plus [+] Moins [-]Blue carbon storage in Fijian seagrass meadows: First insights into carbon, nitrogen and phosphorus content from a tropical southwest Pacific Island
2022
Singh, Shalini | Lal, Monal M. | Southgate, Paul C. | Wairiu, Morgan | Singh, Awnesh
Seagrasses provide vital ecosystem services which include the accumulation and storage of carbon and nutrients in sediments and biomass. Despite their importance in climate change mitigation and adaptation, seagrass ecosystems have been poorly studied, particularly in the Pacific. Therefore, the present study assessed variability in sedimentary and vegetative C, N and P storage in three monospecific seagrass meadows (Halophila ovalis, Halodule pinifolia and Halodule uninervis), reporting baseline data for the first time. Sediment Cₒᵣg stocks ranged from 31 to 47 Mg C ha⁻¹ and varied (p < 0.001) between seagrass meadows, unvegetated areas and locations. Comparison of N and P storage between vegetated meadows and unvegetated areas revealed differences (p < 0.05); implying seagrass meadows function as C, N and P sinks. Differences in species composition and environmental conditions, may play a key role in estimating C, N and P stocks, which are valuable data for conservation and monitoring of seagrass ecosystems.
Afficher plus [+] Moins [-]Trace metal content in sediment cores and seagrass biomass from a tropical southwest Pacific Island
2021
Singh, Shalini | Lal, Monal M. | Southgate, Paul C. | Wairiu, Morgan | Singh, Awnesh
A unique feature of seagrass among other ecosystem services is to have high phytoremediation potential that is a cost-effective plant-based approach and environmentally friendly solution for metal contamination in coastal areas. The goal of this study was to assess the phytoremediation prospective of seagrass for Cu, Fe, Mn and Zn in Fiji Islands. Heavy metal content was measured in sediments and tissues of the seagrasses Halophila ovalis, Halodule pinifolia and Halodule uninervis to test for local-scale differences. The local study shows that metal concentration in sediment and seagrass tissue was significantly variable, regardless of species and sediment type. Sedimentary concentration of Cu, Fe, Mn and Zn obtained in the present study seemed to be lower than that of previous studies. The results support that H. ovalis is a good bioindicator species since it accumulated up to 5-fold more of these metals compared to the Halodule species.
Afficher plus [+] Moins [-]Microplastics in subsurface coastal waters along the southern coast of Viti Levu in Fiji, South Pacific
2020
Dehm, Jasha | Singh, Shubha | Ferreira, Marta | Piovano, Susanna
Microplastics (MPs) remain largely understudied in Small Island Developing States. This study is aimed at comparing the abundance and characteristics of MPs in rural and urban marine coastal sites located along the southern coast of Fiji's main inhabited island, Viti Levu. Collection of subsurface waters (at depth of ca. 0.6 m) was performed at seven sites via Niskin bottle. Samples were filtered over a membrane filter to extract MPs and to allow visual analysis and polymer identification by using attenuated total reflectance in Fourier transform infrared spectroscopy. Findings from this study depict widespread presence of MPs in both urban and rural sites, and show no significant differences in the four parameters studied, i.e. abundance of MP pieces (2.0 vs 1.6 MP/L, respectively), form types (dominance of fibers), size (0.5–0.9 and 1.0–1.4 mm totaling 48% of the samples), and color (blue contributing 30%, and red and black contributing 25% each). These findings challenge the common expectation of a higher MPs pollution in urban areas compared to rural areas.
Afficher plus [+] Moins [-]Over a decade monitoring Fiji's seagrass condition demonstrates resilience to anthropogenic pressures and extreme climate events
2020
McKenzie, Len J. | Yoshida, Rudi L.
Seagrass are an important marine ecosystem of the Fiji Islands. We confirm six seagrass species from the archipelago and defined five broad categories of seagrass habitat. We report, with high confidence, seagrass meadows covering 59.19 km² of Fiji's shallow water habitats from literature and this study. Long-term monitoring of seagrass abundance, species composition, and seed banks at eight sentinel sites, found no long-term trends. Examination of key attributes that affect seagrass resilience identified meadows as predominately enduring and dominated by opportunistic species which had moderate physiological resistance, and high recovery capacity. We examined threats to Fiji's seagrass meadows from extreme climatic events and anthropogenic activities using a suite of indicators, identifying water quality as a major pressure. Based on these findings, we assessed existing protections in Fiji afforded to seagrass and their services. This understanding will help to better manage for seagrass resilience and focus future seagrass research in Fiji.
Afficher plus [+] Moins [-]Promoting sustainable and inclusive oceans management in Pacific islands through women and science
2020
Michalena, Evanthie | Straza, Tiffany R.A. | Singh, Priyatma | Morris, Cherie W. | Hills, Jeremy M.
The question of how to efficiently and effectively manage ocean resources in a sustainable way has reached the forefront of discussion at an international level, but women's contributions to this process have been underestimated or unrecognized. Inclusive management plays a major role in the effective creation, use and adoption of environmental governance, necessitating efforts to measure, monitor and advance inclusivity. In many Pacific island states, there is a lack of disaggregated data collection and management to assist reliable and liable gender-responsive decision-making by national and regional authorities. This lack of information leads to unquantified female contributions and unexplored potential for women to actively contribute to sustainable ocean management as traditional leaders, researchers or science-based managers and in accordance with traditional customs, cultures and processes. This paper examines the contribution of gender-disaggregated data in both (1) effective management of natural resources and (2) measurement and monitoring of the active involvement of women in ocean management. We seek to shift the question from simply “(How) are oceans used by women?” to “How can we build a clear path towards inclusive oceans management using science?”, drawing data mainly from gender and ocean management practices in Pacific Small Island Developing States. This work also seeks to ground in reality the increasing national and international evocations about social equity and avoidance of gender discrimination. Given the existing relationships of Pacific peoples with the ocean and the emerging status of ocean science-based governance, wider integration of science and women in marine management can make an interesting and positive impact in this region.
Afficher plus [+] Moins [-]Corals from the Persian/Arabian Gulf as models for thermotolerant reef-builders: Prevalence of clade C3 Symbiodinium, host fluorescence and ex situ temperature tolerance
2013
Hume, B. | D’Angelo, C. | Burt, J. | Baker, A.C. | Riegl, B. | Wiedenmann, J.
Corals in the Arabian/Persian Gulf endure summer temperatures of up to 36°C, making them ideal subjects to study the mechanisms underlying thermal tolerance. Unexpectedly, we found the “generalist” Symbiodinium clade C3 to be the prevalent symbiont among seven coral species from Abu Dhabi (UAE) waters. Moreover, C3 represented the only dominant symbiont type in Porites spp. from this region. The “thermotolerant” symbionts D1a and C15 were not encountered, indicating that the association with these symbionts cannot be the sole reason for the heat tolerance of Gulf corals. The association of Porites lobata with specific symbiont types (C3 vs. C15) in samples from habitats with very different temperature regimes (Abu Dhabi vs. Fiji) remained unaffected by laboratory culture. During temperature stress experiments specimens from both locations strongly downregulated green fluorescent protein (GFP)-like pigments. However, the Abu Dhabi samples were less prone to bleaching and showed lower mortality.
Afficher plus [+] Moins [-]A temporal assessment of microplastics distribution on the beaches of three remote islands of the Yasawa archipelago, Fiji
2022
Al Nabhani, Khadija | Salzman, Scott | Shimeta, Jeff | Dansie, Andrew | Allinson, Graeme
This is the first study that investigated the presence, distribution, and composition of microplastics, MPs (1-5 mm) on beaches in the Yasawa Islands, Fiji. A temporal assessment over three years on six beaches was undertaken to investigate different beach traits on MP abundance. Average MP concentration was 4.5 ± 11.1 MPs·m⁻² with significantly higher concentrations were found on east-facing beaches than west (p < 0.001), and higher on the storm line compared to the high tide line (p < 0.001). No difference was found between tourist and local beaches (p = 0.21). These results demonstrate the role of current-driven ocean transport of plastic pollution in this part of The South Pacific. ATR FT-IR analysis showed that across all sites 34 % of MPs were polypropylene (PP), 33 % polystyrene (PS), 25 % polyethylene (PE), and 8 % other polymer types. Further studies are needed to assess the potential impacts of MPs on Fiji's coral reefs and marine life.
Afficher plus [+] Moins [-]Policy options to achieve culturally-aware and environmentally-sustainable tourism in Fiji
2019
Tyllianakis, Emmanouil | Grilli, Gaetano | Gibson, Dawn | Ferrini, Silvia | Conejo-Watt, Heather | Luisetti, Tiziana
Increased visitation rates are expected to further impact ecosystems and local communities depending on them to generate income from tourism. We measure how different sustainable tourism management options of such areas in ways that respect the concept of vanua, the Fijian understanding of the connectiveness of the natural environment, humans and traditions, are perceived by a representative sample of potential visitors of the UK population. We then consider some plausible management options and how these may impact welfare. Results show that prospective UK respondents are willing to donate approximately £73 for a management option that enforces medium restrictions by local communities to enter coastal and marine areas in Fiji, so that vanua is respected. A management option that instead denies access to local communities is not seen favourably by prospective UK visitors to Fiji. In terms of time preference, UK respondents, in particular those with previous experiences of tropical areas, prefer environmental projects that restore and protect coastal and marine ecosystems to be completed as soon as possible. Our findings seem to support the introduction of more sustainable and community-based management practices in Fiji as they appear to increase welfare of visitors respecting local traditions and customs, as long as some access is provided to tourists. Donations from tourists or a change in tourism management from a traditional to a more sustainable practice may support the sustainable development of the local coastal communities in Fiji.
Afficher plus [+] Moins [-]The effectiveness of legislative and voluntary strategies to prevent ocean plastic pollution: Lessons from the UK and South Pacific
2021
Tudor, David T. | Williams, Allan T.
The islands of the South Pacific contribute a fraction of the mis-managed plastics in the world's ocean, yet the region is one of the main recipients of its impacts. Based on expert interviews and a review of current strategies to prevent marine plastic pollution in six countries (Australia, New Zealand, Fiji, Tonga, Vanuatu, United Kingdom), this paper identifies several interventions – legislative, financial, voluntary - which governments, organisations and individuals can learn from. Both voluntary and statutory consumer-based behaviour change campaigns are well developed and somewhat successful in several countries. While sub-national policies do not inhibit progress, they are not optimal. Harmonisation across the territories of federal and devolved systems is beneficial, such as container return schemes, levies, and bans. Vanuatu has displayed high ambition, and the challenges in achieving this serve as a case study. A coordinated global strategy with associated legislation aimed at tackling plastic pollution is critical.
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