A Study of the Spatial Distribution and the Seasonal Variation of the Polychaete Community in an Intertidal Flat of the Southern Tatu Estuary

• Main Authors: Wang, Yu Huang, 王豫煌
• Other Authors: Peter Chang
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/75807124216322442704

碩士 === 東海大學 === 環境科學系 === 84 === This study of polychaete worms on an intertidal flat of Southern Tatu Estuary was conducted from November, 1994 to September, 1995. Five core samples were taken bimonthly at each of sixteen sites along four 1 km transects from high tide level to mid-tide level. For one year of investigation, there were, at least, about 27 species of polychaetes in the study area. Four of these were excluded from analysis because of their sparsity. Data for the other 23 species are analyzed through ANOVA, Spearman rank correlation, PCA and canonical correlation analysis to determine the spatial and temporal variation of the whole polychaete community. The results indicate that:1. The total species diversity and density in the mid-tide level where the sediment is fine sand to median sand were far higher than in the high tide level where the sediment is silt to very fine sand.2. The spatial distribution pattern of the polychaete communities is positively correlated with the mean particle diameter of the substrate ( which is more important ) and negatively correlated with the silt-clay content and sorting coefficient ( which is less important).3. Armandia intermedia, Tylonereis bogoyawleskyi, Glycera cf. tesselata, Scoloplos (S.) tumidus and Scolelepis (S.) sp. were the larger dominant species inhabiting the mid-tide level where the sediment is very fine sand to median sand. At the high tide level where the sediment is silt, Perinereis aibuhitensis, Neanthes glandicincta, Laonome albicingillum and two unidentified species of Capitellidae dominated.4. Species richness of all polychaetes in the study area was highest in May, and Simpson''s indexes were higher from March to May. This shows that the populations of the dominant species decreased in abundance and the colonization of some opportunistic species occured in the period.5. The populations of most species showed significant seasonal fluctuation and were most abundant in January and March, which indicates that the breeding of most species occurs in autumn to spring.This study concludes that the dominant polychaete species distributed at different tide level may provide some part of the food resources for the wintering and migrant shorebirds in this area. Because of the diverse infauna flourishing in the mid-tide level with fine sand sediment, this is the essential foraging ground for the support of shorebirds in the whole reserve.