Marine Atlas: Maximizing Benefits for Fiji

northern part of the Fiji’s waters, where photo- synthetically available radiation varies by up to 15 per cent throughout the year. This is in part due to changes in atmospheric conditions, such as cloud cover. In Suva, the average percentage of the sky covered by clouds experiences significant season- al variation, with the cloudiest days occurring from December to March and the least cloudy days from July to September. The chlorophyll-a concentration in Fiji’s waters is generally very low, with concentrations in its off- shore waters less than 0.1 gram per m3 of seawa- ter. Most of the tropical regions of the open oceans have similarly low chlorophyll-a concentrations. In contrast, within temperate and arctic regions, these concentrations can approach 1 gram per m3 of seawater. The shallow coastal regions of Fiji have increased chlorophyll-a concentrations, with up to 3–4 grams per m3 of seawater. Again, this is low compared to many coastal regions around the world, where chlorophyll-a concentrations can reach over 10 grams per m3 of seawater. The low concentrations of chlorophyll-a in Fiji’s waters reflect the low availability of key nutrients. Com- pared to large continental landmasses, with large river discharges that can carry nutrients into the sea, Fiji is a small island nation with comparatively small nutrient inputs into the marine environment. However, at the local or bay scale, nutrient inputs may still be significant (see also chapter “From ridge to reef”). In the south-western tropical Pacific Ocean, strong seasonal and inter-annual variabilities in the chlorophyll-a concentration have been observed (Dupouy et al., 2004). Strong chlorophyll-a enrich- ments have been documented around the Solo- mon Islands, and between New Caledonia and Vanuatu, with weaker enrichments found around Fiji or Tonga. The annual variation in chlorophyll-a around Fiji is up to 20 grams per m3 of seawater in some coastal areas.

Bacterial bloom south of Fiji on 18 October 2010. Though it is impossible to identify the species from space, it is likely that the yellow-green filaments are miles-long colonies of Trichodesmium, a form of cyanobacteria often found in tropical waters. NASA Earth Observatory.

CHLOROPHYLL A CONCENTRATION (milligram/metre 3 )

0.12 mg/m 3

0.04 mg/m 3

No Data

Fiji Provisional EEZ Boundary Archipelagic Baseline

100 50

200 km

Sources : Becker et al, 2009; Claus et al, 2016; NASA Goddard Space Flight Center, 2014; Smith and Sandwell, 1997. Copyright © MACBIO Map produced by GRID-Arendal

Euphausia superba, phytoplankton from the Antarctic, is an example of the basis of the marine food chain.

MAXIMIZING BENEFITS FOR FIJI

SUPPORTING VALUES

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