TDA-IME Project Final Report June, 2013 protection, as ‘bio-shields’, against typhoons and tsunamis, absorbing wave and wind energy (and hence effective for mitigation against some of the expected effects of climate change); 83 education and ecotourism (important on a more location-specific basis). The provision of these mangrove goods and services is predominantly local, and varies considerably between localities. Thus, mangrove loss or degradation is felt primarily locally and severely in the case of mangrove-dependent communities. However, because of the interconnectedness between mangrove areas, and between mangroves and other ecosystems - seagrasses, coral reefs, the open sea, rivers - mangrove, economic valuations should be attempted at transboundary and regional scales. Recent reviews by Salem and Mercer (2012) and Vo et al. (2012) provide comprehensive analyses of the estimated economic values for mangrove ecosystem services based on previously published studies dating from the 1990s (e.g. Lal, 1990; Ruitenbeek, 1992; Sathirathai, 1998). They also identify limitations in the methodologies used for ecosystem valuation and compare the diverse economic data that have been generated using the different methods applied. A recent manual on the economic valuation of mangroves, including methodology for the economic assessment of alternative mangrove management options, is also available (Bann, 2010), as well as an earlier review of mangrove economic valuation methods and results by Spaninks and van Beukering (1997), plus guidelines on similar valuation methods for wetlands and coastal resources by AWB (1991) and Barnton (1994). Ecosystem services are defined by the Millennium Assessment (2005) as “the benefits provided by ecosystems to humans, which contribute to making human life both possible and worth living”. Another definition of the term that is more applicable to mangrove ecosystems is given by Vo et al. (2012): “ecosystem service comprises of all the goods and services provided by natural and modified ecosystems that benefit, sustain and support human wellbeing”. Unfortunately, human society emphasizes the “market-delivered” elements of wellbeing and judges value almost exclusively from market prices (TEEB, 2010). This explains why the non-marketed services provided by ecosystems have consistently been over-looked. The above issue is the most crucial one for policy choices affecting mangroves. Sathirathai (2004), for example, pointed out that in Thailand, because many mangrove ecosystem services are not market-based, they have not been considered in development decisionmaking; decisions have been based on commercial considerations only. Indirect values important to traditional mangrove users, especially the mangroves’ coastal fisheries support function, have largely been ignored by national land-use policy-makers. In her study in Surat Thani, southern Thailand, she showed that conversion of mangroves into a shrimp farm is financially viable as a commercial decision by the owner, but is not economically viable from the view point of society (Sathirathai, 1998). Another crucial consideration in the present analysis, with major implications for a future Strategic Action Plan for transboundary mangroves in Indochina, is the argument put forward by Ronnback et al. (2003) that rehabilitation of coastal ecosystems inevitably will be more expensive than preserving existing mangrove habitat. Ronnback (2007) also found that traditional mangrove users in Kenya derived significantly more environmental services from natural mangroves compared to replanted ones. In other cases, including Asia, however, where extensive mangrove habitat loss or degradation has already occurred, affordable rehabilitation methods are needed to restore the diminished ecosystem services (Vo et al., 2012). Evidence from studies in Cambodia, Malaysia and Thailand also shows that aquatic biodiversity and productivity can be almost as high in rehabilitated sites as in mature mangroves (e.g. Ashton et al., 2003). Moreover, in these and other Asian countries, there are only vestiges left of what can be considered
Transboundary Diagnostic Analysis of Indochina Mangrove Ecosystems
To see the actual publication please follow the link above