 ที่มา:KASETSART UNIVERSITY FISHERIES RESEARCH BULLETINหัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : SPECIES COMPOSITION OF SEAGRASSES AT HAAD CHAO MAI NATIONAL PARK, TRANG PROVINCE, THAILAND) ผู้เขียน: นางกาญจนภาชน์ ลิ่วมโนมนต์, ศาสตราจารย์ ,  Chatcharee Supanwanid สื่อสิ่งพิมพ์:pdf AbstractThe species composition of seagrasses at Haad Chao Mai National Park, Trang Province, was conducted.in March and December 1998 and March 1999. Nine species belonging to six genera of two families were found. Of these, eight species were from Khao Bae Na and the same number from Laem Yong Lam while there were only six species from Ko Muk. The dominant species during the month of March were Halophila ovalis, Halophila decipiens and Enhalus acoroides. All the three dominant species were in flowering and fruiting condition. The occurrence and abundance of other species in the order listed were Cymodocea rotundata, Thalassia hemprichii, Halodule uninervis, Cymodocea serrulata, Syringodium isoetifolium and Halodule pinifolia respectively. All these species were sterile with no evidence of flowers and fruits. Halophila decipiens was the only species disappeared in December. Most of the seagrasses disappeared from Kao Bae Na especially Halophila ovalis which had been the dominant species of this area. |
ที่มา:KASETSART UNIVERSITY FISHERIES RESEARCH BULLETINหัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : QUANTITATIVE ESTIMATION OF THE DISTRIBUTION AND BIOMASS OF SEAGRASSES AT HAAD CHAO MAI NATIONAL PARK, TRANG PROVINCE, THAILAND) ผู้เขียน:Masahiro Nakaoka, Chatcharee Supanwanid สื่อสิ่งพิมพ์:pdf AbstractA seagrass bed at Haad Chao Mai National Park, Trang Province, is one of the largest seagrass beds with the highest species diversity in Thailand. To elucidate distribution and abundance of seagrasses over the entire bed, we carried out a large-scale quantitative census at subtidal and intertidal bottoms covering ca. 18 km2 area. On December 1999, a total of 69 stations were set at subtidal and lower intertidal area, and 183 stations along 10 transect lines at upper intertidal area. At each station, coverage of each seagrass species was recorded and aboveground biomass was estimated by the rapid visual technique developed by Mellers (1991). A total of 8 species (Enhalus acoroides, Halophila ovalis, Thalassia hemprichii, Cymodocea rotundata, C. serrulata, Halodule uninervis, H. pinifolia and Syringodhtm isoetifolium) were recorded by the census. At subtidal and lower intertidal areas, biomass was highest at shallow stations (<2 m) along the coastlines, while seagrass was rarely observed at the deeper stations and at some shallow stations on sand dunes developed at a river mouth. E. acoroides was the most abundant species, followed by H. ovalis and T. hemprichii. Six seagrass species were found at the upper intertidal area. H. ovalis and T. hemprichii were dominant, and they formed monospecific patches at sand dunes and tide pools, respectively. Average aboveground biomass was 1.5 times higher at the intertidal area (15.37 gDW m"2) than the subtidal (10.64 gDW m"2). Therefore, the contribution of intertidal seagrass meadow to total standing stock of the study site (23%) was higher than expected from the proportion of area it occupied (17 %). Distribution, species composition and biomass of the seagrass bed are affected by at least 2 factors; water depth (possibly related to light availability) and physical disturbance such as sand movement. |