577
19.2 Global Mangrove Cover Distribution
As mentioned earlier, mangrove forests are found in tropics and subtropics, between
32°N and 38°S latitudes. Global area under mangrove cover has been estimated to
vary between 11 and 24 million hectares (Giri et al. 2010; FAO 2007; Wilkie and
Fortuner 2003; Spalding et al. 1997; Fisher and Spalding 1993; Finlayson and
Moser 1991). The first attempt to estimate world’s total mangrove cover was done
as part of the FAO and United Nation Environmental Program (UNEP) called
‘Tropical Forest Resources Assessment’ in 1981(FAO & UNEP 1981). As per this
study, the world’s total mangrove area was estimated as 15.6 million hectares.
However, according to FAO (2007), the world’s mangrove area estimated in 2005
was 15.2 million hectares. This study reports that about 20% of the mangrove area
or 3.6 million hectares has been lost since 1980. However, more recently the rate of
net loss in the mangrove area has been slowed down. According to Finlayson and
Moser (1991) the total mangrove area of the world is about 14 million hectares: out
of this the old world tropical mangrove, i.e., the Indo-Pacific tropical zones and
tropical Australia have the most dominated and important mangroves in respect of
species diversity, richness, abundance and succession. World Mangrove Atlas
(Spalding et al. 1997) provides the global mangrove cover area as 18.1 million hectares. The most dominant and single largest mangrove patch of the world is in the
Sunderbans, the Ganga–Brahmaputra-Meghna deltaic regions or estuarine mouths
of both India and Bangladesh (Naskar and Mandal 1999).
The most recent estimates, by Giri et al. (2010), provide the global area under
mangrove cover as 13.77 million hectares, spanning in 118 countries. They have
used GLS data set of 2000. Their estimate was 12.3% lesser than the estimate provided by FAO (2007). GLS is a global data set of Landsat TM images (30 m spatial
resolution, pertaining to 1997–2000 time frame), prepared in partnership between
USGS, NASA, GEO and US Climate Change Science Program (CCSP) and NASA’s
Land Cover and Land Use Program, LCLUC (Gutman et al. 2008). As per the their
mapping, approximately 75% of worlds mangroves are found in the following 15
countries: Indonesia, Australia, Brazil, Mexico, Nigeria, Malaysia, Myanmar, Papua
New, Bangladesh, China, India, Guinea Bissau, Mozambique, Madagascar and
Philippines (in the descending orders of mangrove area). Only 6.9% of the world’s
mangroves are protected under the existing Protected Area Network (IUCNI-IV).
As per the Giri’s study (Giri et al. 2010), largest extent of mangroves was found in
Asia (42% of the global mangroves), followed by Africa (20%), North and central
America – 15%, Oceania – 12% and South America – 11%.Indonesia with largest
mangrove area, accounted for 22.6% of the global mangroves. Australia had the
second largest area under mangrove cover (7.1%). India stood at 11th position,
accounting for 3.1% of the global mangrove cover.
19 Mangrove Inventory, Monitoring, and Health Assessment
19.2 Global Mangrove Cover Distribution
As mentioned earlier, mangrove forests are found in tropics and subtropics, between
32°N and 38°S latitudes. Global area under mangrove cover has been estimated to
vary between 11 and 24 million hectares (Giri et al. 2010; FAO 2007; Wilkie and
Fortuner 2003; Spalding et al. 1997; Fisher and Spalding 1993; Finlayson and
Moser 1991). The first attempt to estimate world’s total mangrove cover was done
as part of the FAO and United Nation Environmental Program (UNEP) called
‘Tropical Forest Resources Assessment’ in 1981(FAO & UNEP 1981). As per this
study, the world’s total mangrove area was estimated as 15.6 million hectares.
However, according to FAO (2007), the world’s mangrove area estimated in 2005
was 15.2 million hectares. This study reports that about 20% of the mangrove area
or 3.6 million hectares has been lost since 1980. However, more recently the rate of
net loss in the mangrove area has been slowed down. According to Finlayson and
Moser (1991) the total mangrove area of the world is about 14 million hectares: out
of this the old world tropical mangrove, i.e., the Indo-Pacific tropical zones and
tropical Australia have the most dominated and important mangroves in respect of
species diversity, richness, abundance and succession. World Mangrove Atlas
(Spalding et al. 1997) provides the global mangrove cover area as 18.1 million hectares. The most dominant and single largest mangrove patch of the world is in the
Sunderbans, the Ganga–Brahmaputra-Meghna deltaic regions or estuarine mouths
of both India and Bangladesh (Naskar and Mandal 1999).
The most recent estimates, by Giri et al. (2010), provide the global area under
mangrove cover as 13.77 million hectares, spanning in 118 countries. They have
used GLS data set of 2000. Their estimate was 12.3% lesser than the estimate provided by FAO (2007). GLS is a global data set of Landsat TM images (30 m spatial
resolution, pertaining to 1997–2000 time frame), prepared in partnership between
USGS, NASA, GEO and US Climate Change Science Program (CCSP) and NASA’s
Land Cover and Land Use Program, LCLUC (Gutman et al. 2008). As per the their
mapping, approximately 75% of worlds mangroves are found in the following 15
countries: Indonesia, Australia, Brazil, Mexico, Nigeria, Malaysia, Myanmar, Papua
New, Bangladesh, China, India, Guinea Bissau, Mozambique, Madagascar and
Philippines (in the descending orders of mangrove area). Only 6.9% of the world’s
mangroves are protected under the existing Protected Area Network (IUCNI-IV).
As per the Giri’s study (Giri et al. 2010), largest extent of mangroves was found in
Asia (42% of the global mangroves), followed by Africa (20%), North and central
America – 15%, Oceania – 12% and South America – 11%.Indonesia with largest
mangrove area, accounted for 22.6% of the global mangroves. Australia had the
second largest area under mangrove cover (7.1%). India stood at 11th position,
accounting for 3.1% of the global mangrove cover.
19 Mangrove Inventory, Monitoring, and Health Assessment