Species of seagrass

Distribution of seagrass

In 1986, the survey of seagrass beds in Thailand was started in the Andaman Sea, especially Ao Phang Nga. In 1991, the PMBC also studied the distribution of seagrass along the Andaman Coast, starting from Ranong to Satun Provinces (Chansang and Poovachiranon, 1994). For the Gulf of Thailand, seagrass beds were found in several areas such as Ao Khung Kraben, Chantaburi Province (Aryuthaka, 1991), Ko Pha Ngan and Ko Samui Island, Suratthani Province (Sudara et al., 1989, 1992) and Ao Pattani (Intharasook, 1999). In addition, taxonomic study of seagrasses in Thailand was reported by Lewmanomont et al. (1996) indicating that all species were found in Thai Waters, except Ruppia maritime which only found in the Gulf of Thailand. Seagrass beds can be found in the brackish waters or estuary, close to mangrove forest, shallow water with sandy or silt bottom as well as in the deeper area closed to coral reefs. Generally, seagrass beds in the Andaman Sea are more abundant than which in the Gulf of Thailand. The seagrass beds in The Andaman Sea are distributed near the coasts of islands covering all provinces, i.e., Ranong, Phang Nga, Phuket, Krabi, Trang and Satun Provinces and the largest seagrass beds is found in Ko Talibong, Trang Province. Meanwhile, the seagrass beds in the Gulf of Thailand are found near the coasts of many provinces and some islands, i.e., Trat, Chanthaburi, Rayong, Chonburi, Phetchaburi, Prachuap Khiri Khan, Chumporn, Surat Thani,  Nakhon Si Thammarat, Pattalung, Songkhla, Pattani and Narathiwat Provinces. The list of seagrass species found in each province have been shown in Table 

Species Diversity

In Thai Waters, seagrasses are distributed along the coastal areas of both mainland and islands, consisted of 12 species dividing based on their leaf structure into 2 groups: long flat leaves or long circle leaves and short oval leaves. The name of seagrasses are different depending on each local areas, the Gulf of Thailand and the Andaman Sea. Poovachiranon (1991) is a pioneer of naming seagrass of The Andaman Sea in Thai based on both local name and specific characteristics of each seagrass (Figure and Table) as follows:

A group of long-flat leaves or long circle leaves includes Enhalus acorides, Syringodium isoetifolium, Halodule uninervis, Halodule pinifolia, Ruppia maritime, Cymodocea rotundata, Cymodocea serrulata, Thalassia hemprichii

A group of short oval flat leaves includes Halophila ovalis, Halophila minor, Halophila decipiens, Halophila beccarii

Distribution of seagrass

In 1986, the survey of seagrass beds in Thailand was started in the Andaman Sea, especially Ao Phang Nga. In 1991, the PMBC also studied the distribution of seagrass along the Andaman Coast, starting from Ranong to Satun Provinces (Chansang and Poovachiranon, 1994). For the Gulf of Thailand, seagrass beds were found in several areas such as Ao Khung Kraben, Chantaburi Province (Aryuthaka, 1991), Ko Pha Ngan and Ko Samui Island, Suratthani Province (Sudara et al., 1989, 1992) and Ao Pattani (Intharasook, 1999). In addition, taxonomic study of seagrasses in Thailand was reported by Lewmanomont et al. (1996) indicating that all species were found in Thai Waters, except Ruppia maritime which only found in the Gulf of Thailand. Seagrass beds can be found in the brackish waters or estuary, close to mangrove forest, shallow water with sandy or silt bottom as well as in the deeper area closed to coral reefs. Generally, seagrass beds in the Andaman Sea are more abundant than which in the Gulf of Thailand. The seagrass beds in The Andaman Sea are distributed near the coasts of islands covering all provinces, i.e., Ranong, Phang Nga, Phuket, Krabi, Trang and Satun Provinces and the largest seagrass beds is found in Ko Talibong, Trang Province. Meanwhile, the seagrass beds in the Gulf of Thailand are found near the coasts of many provinces and some islands, i.e., Trat, Chanthaburi, Rayong, Chonburi, Phetchaburi, Prachuap Khiri Khan, Chumporn, Surat Thani,  Nakhon Si Thammarat, Pattalung, Songkhla, Pattani and Narathiwat Provinces. The list of seagrass species found in each province have been shown in Table

  

  

  

  

Examples of seagrass beds found in Thailand

Table  List of seagrass species found in each province in the Gulf of Thailand and The Andaman Sea

                                Source: Department of Marine and Coastal Resources (2012b)

A group of long-flat leaves or long circle leaves
(Enhalus acorides)
(Syringodium isoetifolium)
(Halodule uninervis) 
(Halodule pinifolia)
 (Ruppia maritima)
 (Cymodocea rotundata)
(Cymodocea serrulata)
(Thalassia hemprichii)
A group of short oval flat leaves
 (Halophila ovalis)
(Halophila minor)
 (Halophila decipiens)
(Halophila beccarii)
   

 

Enhalus acorides
Syringodium isoetifolium
Halodule uninervis
Halodule pinifolia
Ruppia maritima
Cymodocea rotundata
Cymodocea serrulata
halassia hemprichii
Halophila ovalis
Halophila minor
Halophila decipiens
Halophila beccarii