NUKU’ALOFA-January 4: 10.10am (R2R Media): Mangrove replanting is a top priority for the “Ridge To Reef” project, under the Department of Environment here in Nuku’alofa.
Communities around the Fanrga’uta Lagoon Catchment area are working with the R2R project and the Department of Environment in learning the importance of re-planting mangroves.
In November the The Ridge Two Reef (R2R) Mangrove Rehabilitation Training continued in Folaha Village, here on Tongatapu.
This time the training was done with the members of the “Hakeaki’i e Lotu, Ako mo e ‘Atakai” Youth Group of Loutokaiano.
Staff from the R2R project and the Environment Department facilitated the training and spent the day with the youth group members.
This is part of the campaign to try and re-plant mangrove along the Fanga’uta Lagoon Catchment area and save our environment.
Replanting also started at Longoteme as well late last week, close to 200 seedlings, mainly of Rhizophora breed, were planted.
The team had to clean up first.
The team looking after this project have identified that the three sites of Holonga, Talasiu and Longoteme still need replanting throughout the rest of this year to evenly cover each proposed area.
According to Tonga’s National Biodiversity Strategy and Action Plan (NBSAP, 2006), the Kingdom has approximately 1,000 hectares (10 km) of mangrove area with the largest area, of 50 hectares (5 km), located in the Fanga’uta Lagoon.
A recent report reveals that only 3.36 km of mangroves remain in the Kingdom.
Tonga has eight (8) mangrove species.
Two of the most common species in Tonga and on the main island of Tongatapu are Rhizophora samoensis and Rhizophora stylosa.
The mangrove areas have significant uses for local people, providing nursery ground for many fish and crustaceans as well as being traditionally exploited for construction wood, the gathering of crabs, fish and fuel wood, and used for local medicines, dyes and tannins. In 1983, it was found that 44.5 km (of the total 58 km) of the Fanga’uta lagoon system shoreline were covered by mangrove forests.
The coverage was found to be greatest in the western sections in the Pe’a Sector and the Folaha Sector (Fangakakau) (about 30 to 35 km), with only about 14 km of coastline covered by mangroves in the eastern sectors out of a shoreline length of 24 km.
The mangrove area along the southern coast of the Mu’a Sector is very narrow due to primarily consisting of raised limestone making it less suitable for mangrove growth.
The mangrove cover has since significantly reduced with losses and threats from coastal developments and land reclamation, particularly on shores adjacent to Nuku’alofa, unsustainable stripping of the mangroves for tannins for tapa making and medicine, and cutting the mangroves for firewood and building materials.
Habitat degradation and coastal erosion
The mangrove area of Tonga is small in global terms, but the community structure of mangroves in the Kingdom makes them unique among the world’s mangroves.
The mangrove ecosystem, however, has been reduced in area by tree cutting or reclaiming areas. The resources have been damaged by unsustainable developments and uses including dredging, reclamation and domestically raised pigs.
The mangrove areas have significant uses for local people, being traditionally exploited for construction wood, and the gathering of crabs, fish and fuel wood.
Dredging in the lagoon affects the tidal height and the normal circulation of the lagoon.
Land reclamation has resulted in the destruction and abuse of the mangrove areas, the sanctuary and breeding ground for marine aquatic organisms.
Clearing of mangrove forests, construction of inappropriate seawalls, depletion of sand on beaches (beach sand mining was banned in 2007, but this is not strictly enforced), and the accumulation of solid wastes either washed onto the shore or in many cases deliberately dumped along the shore and in the mangroves have contributed to coastal erosion and loss of habitats in the lagoon.
Continued land reclamation for town allotments from the shrinking mangroves forest in and around the Fanga’uta lagoon poses a serious threat to the mangrove ecosystem.
Coastal encroachment will lead to pollution to the lagoon as a result of human waste and rubbish disposals.
The damage can be traced back to a lack of effective land-use planning and inequality in land allocation.
The Ridge to Reef project is funded by the United Nations Development Program and the GEF.