A Study of the Differences with the Sediment Component and the Crab and Polychaete Faunas between the Interior and Exterior Mudflat in the Semi-enclosed Embankment of the Southern Tatu Estuary.

• Main Authors: Su, Hsiao Yin, 蘇曉音
• Other Authors: Peter Chen
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/97884611189694783368

碩士 === 東海大學 === 環境科學系 === 91 === Abstract A study was conducted from March 2001 to January 2002. There are sixteen core samples in the four lines set up in the interior and exterior of the fish farm in the southern Tatu estuary. These samples collect sediment structure (organic material content, particle size, sanility and sand temperature) and benthic fauna community component (crabs and polychaetes) in the Tatu estuary during whole year. The research compares the difference between crabs and polychaetes. The result indicated for a year investigation:Due to the fish farm isolated by the artificial building, most of the components in the interior sediment are sandy silts (sZ) and silts (Z). The components in the exterior sediment is silty sand (zS) and sand (S). In September 2001, the components in the interior and exterior sediments of the fish farm affected by the erosion of the typhoon accident are deviation to sandy silt. Then the components of interior sediments gradually became silts after the interior mudflat isolated by the embankment. The average organic material contents in the interior mudflat are 2.05±0.29%. The interior amounts are higher than the exterior of the fish farm. The data displays 1.17±0.22%. The core samples, A2 and A3, in the outlet of the fish farm indicate fluctuant variation affected by the stream. At the same time, the contents obviously display extreme differences between the fish farm(p＜0.0001). Focused on the crabs, there are four families, seven genus and thirteen species of crabs collected for one year. The species average densities, abundances and variations of crabs in the interior mudflat are more biodiversity than the exterior. The average densities indicate 12.5 to 28.1, abundances indicate 1.47 to 0.94 and variations indicate 0.73 to 0.05. The result displays the inside mudflat is the better environment for developing the biodiversity. Especially are the core samples of the fish farm inlet B1, A3 and A1. Focused on the polychaetes, there are four orders and eleven families polychaetes. The species average densities indicates 8.2 to 5.9, abundances indicate1.21 to 1.08 and the variations indicate 0.64 to 066.The result displays the densities of polychaetes in the interior mudflat are more than the exterior but variations are closed. In addition, the amounts of the crabs and polychaetes fauna community generate largely in fall. The result concluded that embankment built leads to different sediment components between interior and exterior mudflat. Similarly, habits chosen by different between crabs and polychaetes in spatiotemporal distribution and seasonal variations.