Download - Pacific Disaster Net

http://www.samoaobserver.ws/other/environment/7784-mangroves-can-help-us-adapt-to-climate-change
Mangroves can help us adapt to climate change
Thursday, 31 October 2013
The majority of the population of Samoa live near the coastal areas. These communities rely heavily
on the resources present nearby for daily sustenance and income. Mangrove ecosystems are part of
these resources and they have been around for a long time providing various services to these same
communities. An example of a service is shoreline protection.
Climate change poses threats to communities which do not have shoreline protection, threats so
devastating which can leave communities or coasts uninhabitable by people. Examples of this are
the countries who are suffering severely from sea level rise, including Tuvalu, Vanuatu, and the
Marshall Islands.
What are some of the impacts of climate change on our islands?
Extreme weather events such as more severe storms, droughts, heavy rainfalls are likely to occur.
Under climate change, there may be fewer cyclones, but their intensity will be higher - such as when
Cyclone Evan hit Samoa causing death, and destruction of homes and infrastructure not usually
caused by a category 2-3 cyclone. Cylcones are likely to increase in their average maximum wind
speed of by between 2% and 11%
Also, sea level is rising in Samoa. (O le a si’isi’i pea i luga i lenei seneturi le maualuga o le sami
latalata ane i Samoa.) Sea level has risen near Samoa by about 4 mm per year since 1993. By 2030,
under a high emissions scenario, this rise in sea level is projected to be in the range of 5-15cm.
Combined with natural year to year changes, this rise means there will be an increase in coastal
flooding and storm surges, because of climate change or global warming.
Sea level rise is when the level of the sea increases or rises. This is caused by the polar ice caps
melting and thermal expansion of the sea surface due to the hotter temperatures. In Samoa, sea
level has risen by 4mm since 1993 and will continue to rise. This is slightly larger than the global
average of 2.8–3.6 mm per year and may be influenced also by El Niño. Combined with natural year
to year changes, this rise means there will be an increase in coastal flooding and storm surges. SO,
“what are we gonna do about it now?”
1
Coastal management, such as planting mangroves, is an important response to protect Samoa from
the effects of more intense storms and sea level rise.
What are mangroves?
Mangroves are unique ecosystems that live half way between the land and sea. They are a very
productive ecosystem and are a source of renewable resources in terms of wide range of important
roles they provide on a continuous basis. They are scientifically recognised as bio diverse wetlands in
the country. Yet these unique coastal environments are among the most disregarded and fast
depleting habitats. Plants identified as mangroves represent over 80 species worldwide of which
only three are found in Samoa. These are Rhizophora samoansis, Bruguira gymnorrhiza and the
rarest of the three, Xylocarpus moluccensis
How can mangroves help against climate change?
Mangroves act as bio shields breaking big waves that approach the shores. They can also minimise
the erosion on coastal areas, but not only that, mangroves greatly contribute to the reducing of
carbon dioxide in the air. Local resident of Vaiusu, Tagaloa Eteuati Mataia, commented on how the
mangroves saved his family from experiencing flooding and inundation of the coast behind their
home.
What are some of the importance of mangroves?
During one of our fieldtrips to Vaiusu, we interviewed a local resident, Tagaloa Eteuati Mataia, who
had lived there for more than 30 years. He had noticed over the years that the mangroves were less
dense today than they were before, and while they still have many resources from the mangroves,
there were less these days than before. We asked him to tell us some of the important roles that the
mangroves have provided for his village over the past years, up until today. He replied, “Many of us
rely heavily on mangroves for food, but not just that, the resources in the mangroves, such as fish,
lobsters and crabs, are often sold by our villagers for income.
There are some of us who don’t have jobs but can still rely on these resources. We also enjoy the
fresh cool air from the mangroves.“
As he had mentioned, mangroves do indeed provide many resources and benefits to us and the
environment. Food can be obtained from mangroves habitat and if managed properly, it can be a
sustainable food source. Resources found in their areas can also be sold for income (prawns, crabs,
fish, wood...etc). As for the environment, mangroves are inhabited by marine and terrestrial species.
Many of these species use mangroves as a nursery and breeding grounds.
What are some of the threats mangroves are facing?
Poor land Management When land is cleared for construction or agricultural purposes, the soil is
easily washed away during heavy rains. This dirt and sediment is carried downstream to the
mangrove forest where it can cover the roots and kill the trees and affect the animals that live in the
water.
Cutting the mangrove forest Cutting some trees will not destroy the mangrove forest if it is done in
a sustainable way. Some people tend to cut more than they need. It is important to remember that
2
mangroves are not fast growing trees. “Sustainable” means meeting the needs of the present
without diminishing the ability of people, other species, or future generations to survive.
Water pollution and rubbish Oil and gasoline from faulty outboard motors and spills create a thin
film that sticks to the mangrove roots. Household rubbish like plastic bags and containers
contaminate the mangrove areas endangering the marine life that live there.
Construction and reclamation of land Large areas of mangroves are being cleared and filled. These
reclaimed areas alter or totally stop the amount of fresh water entering the mangrove areas.
Mangroves need a mixture of fresh and salt water to grow. Any changes in this mixture will affect
the growth and health of the trees. Land reclamation is when people cut down trees or clear areas
to reclaim the land for other uses. SO, “What are we gonna do about it now?” What can we do
together as a community to help save mangroves now?
We can raise awareness on how important mangroves are to coastal areas on fighting climate
change, and how important the resources found in mangroves are, by writing about it (like this!),
talking about it, or producing TV and radio articles about it.
We can create more mangrove conservation areas and clean them as often as we can to keep it
pollution free.
We can replant mangroves again on coastal areas and enforce laws that will prevent anyone from
damaging them.
During all our fieldtrips, we had noticed some of the impacts that climate change have caused to our
environment.
Climate change is a big issue, but mangroves just might be our secret weapon to adapting against it.
We all know that mangroves can help Samoa. The only task left to do is to act now and protect and
preserve the mangroves we have.
3