Post on 25-Dec-2021
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