Understanding Economic Values of SeagrassEcosystem and Implications for Decision

Making: A Case Study of Trang Province,Southern Thailand

bluecarbonblog.blogspot.com

Orapan Nabangchang;

Economy and Environment Institute of theLower Mekong Sub Region (EEI-LMS)

orapann@gmail.com

THE EAST ASIAN SEAS CONGRESS 2015

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Worldwide, there are 60 species. This mapshows where they are distributed

Worldwide, there are 60 species. This mapshows where they are distributed

Thailand has 13 sea grass species. Thetotal area is118,665 rai which isdistributed both on the Gulf side and theAndaman coasts.

11 of the 13 seagrassspecies can be found on thecoasts of Trang, making thisthe province with the highestconcentration of sea grass

Capturing non-use values by using Choice Experiment• Examine tradeoffs by asking respondents to choose between

options defined by attributes.• Provide value of overall changes as well as individual attribute levels

Advantages Disadvantages

• Obtains more information from eachsubject

• Makes subjects think about trade-offs and thoroughly examinepreferences

• Allows for the valuation of both theproduct and its attributes

• Has been used extensively inmarket research and productdevelopment

• Can test some properties of utilitytheory / decision making

• Cognitively challenging for subjects

• Requires at least as muchinformation to be provided as othertechniques

• Cross-section/time-series, discretenature of data pose econometricchallenges

Why sea grass beds areimportant

Without seagrass, there willbe no dugongsbecause they feedonly seagrass

A dugong can eatup to 40 kgs ofseagrass per day

Marine turtles alsofeed on sea grassespecially greenturtles

A green turtle caneat up to 2 kgs ofseagrass per day

Seagrass beds therefore guarantee sustainability of incomefor coastal fisheries in Trang province. It is also a guranteefor food security for coastal communities.

Seagrass ecosystem provides habitat, shelter, nursery grounds andfood for aquatic species

Apart from various fish species, a diversity of marine life can be foundsuch as sea urchins, shrimps, muscles, etc.

Recently, scientists have tried to create awareness about theimportance of sea grass in producing oxygen, sequestering and storingcarbon

Produces 10 liters of oxygen each dayOne square meter of seagrass

ผลิต

1 rai of sea grass cansequester 48 tons ofcarbon/year

This is equivalent tothe green house gasemitted if you drive acar for a distance of3,350 kilometers

Sea grass’s carbon sequestering and storagefunction is of direct relevance to what mant aretalking about today, that is concentration ofGHG and global warming

Scientists have estimated that seagrass bedssequester and store around 15% of CO2

This means that reduction in the area of seagrassbeds will also mean greater concentration of GHGin the atmosphere

The benefits of clear coastal water are:1.The sun can shine to greater sea depths; seagrass, like plants on land, needsunlight2.The more pollutants that sea grass can filter, the less pollutant that can spread tothe coral reefs

Not clearNot clear ClearClear Very clearVery clear

When we talkabout waterclarity, this is

what we mean

When we talkabout waterclarity, this is

what we mean

One other benefit is filtering pollutants such as nutrients, chemicalsand sediments.

The 3 marine ecosystems, mangroves, sea grass and corals are interdependent

CoralreefsCoralreefsSea graasSea graas MangrovesMangroves

A standard football field is 106 x 68 meter or 7,140 square metersA standard football field is 106 x 68 meter or 7,140 square meters

This survey is being conducted because, similar tomany other areas around the world, the sea grass bedsof Trang province is gradually declining

This survey is being conducted because, similar tomany other areas around the world, the sea grass bedsof Trang province is gradually declining

Every hour each day,sea grass beds around the world is disappearingequivalent to an area of around 2 football fields.Every hour each day,sea grass beds around the world is disappearingequivalent to an area of around 2 football fields.

I would like to take just a few moments toexplain the reasons why this is happeningI would like to take just a few moments to

explain the reasons why this is happening

One of the reason for the deterioration of coastal water quality isthe increasing concentration nutrient and pollutants from land-based activities (from communities, factories and chemicalresidues from fertilizer and pesticides which is drained into the sea.

One of the reason for the deterioration of coastal water quality isthe increasing concentration nutrient and pollutants from land-based activities (from communities, factories and chemicalresidues from fertilizer and pesticides which is drained into the sea.

These pollutants (nutrients) speeds the growth of planktonscompete for the necessary nutrients for the growth of sea grass.Increasing concentration of certain chemical pollutants can alsobe harmful for marine life living in the sea grass beds.

These pollutants (nutrients) speeds the growth of planktonscompete for the necessary nutrients for the growth of sea grass.Increasing concentration of certain chemical pollutants can alsobe harmful for marine life living in the sea grass beds.

The increasing concentration of planktons, sediment and othersuspended particles will reduce the clarity of the coastal waters,blocking the sunlight which negatively affect the growth of thesea grass.

The increasing concentration of planktons, sediment and othersuspended particles will reduce the clarity of the coastal waters,blocking the sunlight which negatively affect the growth of thesea grass.

Anchoring boatsAnchoring boats

Fishing andharvestingsea urchins,shrimps, etc.in theseagrassbeds

Fishing andharvestingsea urchins,shrimps, etc.in theseagrassbeds

Dredging tofacilitatenavigation

Dredging tofacilitatenavigation

Increasingsediments whichblock the sunlightnecessary forseagrass growth

Increasingsediments whichblock the sunlightnecessary forseagrass growth

Other reasons why sea grass are disappearing

Measure 1: Restoring and replanting seagrass beds Presently, there are on-going local efforts to replant sea grass

In Trang, replanting will be done 3 times a year. Each time,an area of 25 square meters of sea grass will be planted.

Every year, area replanted is 75 square meters

Why these measures are necessary

!

!

or like thisor like this

This is how sea grass isplanted, in 5 x 5 metersparcel. The parcels don’thave to be continuous butseparated

This is how sea grass isplanted, in 5 x 5 metersparcel. The parcels don’thave to be continuous butseparated

With more budget,more parcels canbe replanted, likethis

With more budget,more parcels canbe replanted, likethis

• Why is it being replanted in patches?• That’s because, left undisturbed, the seagrass will spread twice the

area originally planted without having to plant the whole area.

1 year afterwards 2 years afterwards

If we plant more patches to begin with, the wholeareawill be covered with sea grass in a faster time

Year planted

1 year afterwards 2 years afterwardsYear planted

Measure 2: Controlling and reducingpollution at source

If we can reduce pollution and the sediment at sources (normally land-based), coastal waters can be improved and will be more suitable for seagrass growth

If we can reduce pollution and the sediment at sources (normally land-based), coastal waters can be improved and will be more suitable for seagrass growth

If seagrass beds are in better condition, they can better filter sediments, nutrientsand other pollutants before they reach the coral reefs

And the water will be clearer

Measure 3: Dugong Conservation

Dugong is an endangered specie.In Trang, there are only 130dugongs

Since survival of the dugongsdepend on abundance of seagrass.. Conservation of sea grassbeds is therefore an importantmeasure to reduce the risk ofdugong extinction But to preserve the

sea grass beds alonemay not be sufficient

If the population reduces futher,there is a high risk that they willbecome extinct in these waters

Dugongs are mammals. So if the getcaught in fishing nets, or if they areinjured by boat propellors and areunable to surface to breathe, theywill drown

But to do this, we need to know. where they roam where they sleep and where they feed

One way to provide protection isto declare certain areas that arehabitat or feeding grounds assanctuaries

Because the dugongs face a number of other threats….

We will then have informationabout where they goWe will then have informationabout where they go

These red dots will provideinformation about the areas thatshould be their sanctuaries

These red dots will provideinformation about the areas thatshould be their sanctuaries

Dugongs move in groups(normally about 10 per group)

Dugongs move in groups(normally about 10 per group)

So we don’t tag all of them but just one andwe will know where the group move

So we don’t tag all of them but just one andwe will know where the group move

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Type of value MillionUSD

Use value from Fisheries 1.2Use value from Tourism 5.5Indirect use value from carbonsequestration 65Non-use value 275