PT Unknown
AU Vo, QT
TI Valuation of Mangrove Ecosystems along the Coast of the Mekong Delta in Vietnam an approach combining socio-economic and remote sensing methods
PY 2013
PU Christian-Albrechts-Universität zu Kiel
WP https://macau.uni-kiel.de/receive/diss_mods_00011971
LA en
DE Mangrove ecosystem; economic valuation; household survey; remote sensing; Mekong Delta
AB Mangrove ecosystem is among the most productive and valuable eosystems in the world.The services provided by mangrove ecosystems to human well-being are well acknowledged in literature. Mangrove forests provide not only direct use values such as timber materials and fisheries  resources  but  also  indirect  use  values, for  instance  coastal  protection,  carbon sequestration as well as  biodiversity. Although mangrove forests play an important role in 
providing goods and services to humans in both direct and indirect ways, they are declining at alarming  rates.  Overexploitation  of  mangrove  for  timber, urban  development,  increase population in coastal areas, and especially conversion to aquaculture are the major threats to mangrove  forests  worldwide.  Over  the last two decades, many  studies  on  the  valuation of mangrove ecosystems using different valuation approaches have been carried out in order to increase  the  awareness  of  decision  makers  to  mangrove  ecosystems.  This  dissertation investigates a new approach for quantifying the value of mangrove ecosystem services using remote sensing and  household  socio-economic data. Specifically,  the  method differentiates mangrove cover fractions in a mangrove-aquaculture integrated farming system in Ca Mau Province,  Mekong  Delta  using  an  object-based  approach.  Ca  Mau  Province  serves  as  an interesting case study as it has special conditions. First, it is the Province that hosts one of the largest  mangrove  forest  areas  in  the  Mekong  Delta.  Second,  mangrove  forests  in  this Province  have  been  declining  rapidly  due  to  expansion  of  shrimp  farming.  Last,  it  is  the Province  that  has  special  characteristics  of  the  integrated  mangrove-quaculture  farming system, where mangroves are planted in a shrimp pond with different mangroves densities. 
This dissertation reviews a comprehensive overview of methods applied for the valuation of mangrove  ecosystem  services  undertaken  for  the  last  decades.  The  main  findings  of  this 
research include the following: 1) a need for site/landscape-specific valuation of mangrove ecosystem due to the socio-economic context as well as inconsistency in the value-transfer approach;  monetary  valuation  should  be  used  to  increase  awareness  of  the  importance  of mangrove  ecosystems  to  decision akers/local communities. 2) developed  an object-based approach  for  estimating  the  percentage  of  mangroves  in  mixed  mangrove-aquaculture farming  systems.  This  approach  is  a  first  attempt  to  quantitatively  estimate  mangrove percentages within the special mangrove-aquaculture farming system in the Mekong Delta of Vietnam. The method comprises multi-resolution segmentation and classification of SPOT5 data using a decision tree approach as well as local knowledge from the region of interest. The results demonstrate  that  the  predominantly  mono-cultivation areas,  i.e.,  above  70%  or below  30%  mangrove  forests,  were detected  with  high  accuracies  compared  with  existing 
approaches, 3) the valuation  of  mangrove ecosystem services using combined approach of remote  sensing  and  socio-economic  household  survey  data.  The  total  estimated  value  was 
US$  600  million/year  for  187,533  ha  with  the  mean  value  was  US$3,000/ha/year,  which significantly greater than gross domestic product (GDP) of the Province (US$ 1.25 million in 
2010). The results demonstrate advancements in remote sensing techniques in combination with  household  survey  data  in  quantifying  the  value  of  mangrove  ecosystems.  However, 
future  challenges  remain  before  this  approach  can  be  applied  in  monitoring  the  extent  of mangrove  and  estimating  the  total  economic  value  of  the  mangrove  ecosystem.  Based  on these results, future research should focus on the integration of additional geodata, such as cadastral maps in the segmentation process, or emerging remote sensing technologies such as 
LiDAR  or  hyper-spectral  data  to  characterize  mangrove  species  and  structure.  Primary research on the valuation of recreation, water filtration or biodiversity needs to be done in 
order to estimate the total economic value of mangrove ecosystems.
PI Kiel
ER