Wetlands have been all over the national news of late, as the International Convention on Wetlands, or Ramsar Convention, chose to hold its first ever world wetlands week in Seychelles. Inland water ecosystems in Seychelles are of great biodiversity significance. Small freshwater ecosystems isolated by a 1,000 miles of salt water and 70 million years of evolution are certain to contain high levels of endemic fauna much of which has yet to be properly studied.
The Ramsar definition of wetlands is much broader than inland water ecosystems however and includes lakes, rivers, swamps, marshes, wet grasslands, peat lands, estuaries and areas of marine water the depth of which is 6 metres or less at low tide. In the Seychelles context this includes fringing coral reefs and their lagoons and so has extensive environmental and socio-economic relevance in the local context. It was therefore interesting to note the repeated references in media interviews to wetlands’ importance in mitigating the impacts of climate change and indeed in mitigating disaster events.
Healthy fringing coral reefs can provide very significant protection to the coastland, they surround, from wave action and even attenuate some of the force of a tidal wave. Mangroves in particular are considered to be very important for coastal protection with various examples coming out of the 2004 Tsunami where coastal areas with mangroves fared much better than adjacent areas where the mangroves had been removed.
In Seychelles one of the key considerations is management of the water cycle from catchment areas through streams and rivers to coastal wetlands and their drainage into the sea. One of the features of changing weather patterns in Seychelles in recent years is that while the average amount of rain falling during the rainy season is remaining reasonably stable the nature of the rainfall is changing. Rain is tending to come in shorter and heavier bursts. This poses various problems for the main granitic islands which with their steep topography and very small area experience a rapid run-off of precipitation into the sea. Firstly, of course, it means that the provision of potable water is more problematic as brief but very heavy rain rapidly exceeds the capacity of the small river dams and runs into the sea before any large quantity can be pumped to the La Gogue reservoir.
Likewise this rapid flow of water can cause downstream problems through flooding of coastal plains. When Europeans first explored the granite islands they reported that much of the coastal plains consisted of wetlands which they considered to be ideal for rice production. As time passed much of this low-lying land was reclaimed by early settlers for development. Today this means that various portions of the developed coastal plains are prone to flooding. The capital Victoria is itself largely built on land reclaimed from the sea between 50 and 100 years ago – the former mudflats now host the capitals shopping centres, bus terminal etc... whilst the rivers and streams have been straightened and canalised. The vulnerability of such areas to flooding was emphasised by the heavy rains of 1998.
The first way agencies typically address such concerns is by “improving” drainage through the widening and deepening of drainage channels and marsh outlets. This attains the objective of increasing outflow and shortening and lessening the period and extent of flood events but can give rise to other problems.
Another approach though offering much more gradual results is the integrated management of entire catchment areas. The International Strategy for Disaster Reduction (ISDR) cites sound environmental management as a key factor in the reduction of the instances and impact of disasters. In the Seychelles context this means optimising vegetation cover in catchment areas and along water courses. In this case native vegetation is much better as natural ecosystems have greater structural diversity and integrity and can absorb and hold more water than habitats dominated by invasive species.
Catchment areas if managed properly can act as enormous sponges, capturing and holding vast amounts of water and allowing it to drain off much more slowly resulting in better water retention, slower flow rates and hence less downstream flooding.
Wetlands likewise can be used to mitigate flooding and reduce offshore siltation with its knock-on impacts upon reef health and lagoon fishery production by enhancing their capacity to hold and filter water.
One of the main aspects of the “Seychelles Disaster Preparedness and Response Project” is the mainstreaming of Disaster Risk Reduction (DRR) into other sectoral plans. The environment sector in Seychelles is currently going through a very dynamic phase of project implementation courtesy of GEF-funded projects being rolled-out through the UNDP office in Seychelles. The Department of Risk and Disaster Management (DRDM) is therefore seeking to work with these projects to integrate DRR. To further this end DRDM will soon be making presentations on its project to the national environmental steering committee and the steering committee of a new environmental management capacity building project. It will further more be targeting aspects of the GEF Biodiversity Mainstreaming project and the Sustainable Land Management project specifically with regard to enhanced management of the water cycle for disaster reduction as both those projects will be investigating aspects of watershed management.
Such an approach of inter-project and inter-sectoral cooperation offers considerable scope for the realisation of synergies and the enhanced utilisation of donor funds to attain the objectives of sound environmental management integrating the tenants of disaster risk reduction.
As these activities continue and the process of DRR integration progresses we will report further so please do check back periodically.
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