澎湖岐頭彎的海筆數量與分布研究

Population and Distribution of Sea Pen (Virgularia juncea) in Chitou Bay, Penghu

為了明瞭海筆（Virgularia juncea）在岐頭灣的狀況，本研究利用GPS，並配合潮汐、地形及海筆的生物習性，調查潮間帶及亞潮帶的海筆分布及數量。結果顯示，岐頭灣的海筆集中分布在岐頭灣的中央以北，分布範圍23°38.530'-38.740' N，119°36.280'-36.560' E。可測量的海筆分布面積約6.1ha，該區域的海筆數量介於0-27 m^（-2），平均密度為2.9 m^（-2）。分布的位置約在低潮線附近。海筆會棲息在底質粒度中間值介於極粗砂至小礫之間，且篩選度介於尚佳與不佳之間。當底土粒度中間值為細礫且篩選度不佳時，會有較高的海筆密度。

To understand the condition of sea pen (Virgularia juncea) in Chitou Bay, Global Positioning System (GPS) was used to investigate the population and distribution of sea pen in the intertidal and subtidal zones. Tides, terrain, and biological behavior of sea pens were also taken into consideration. Results show that sea pens were distributed in the center of Chitou Bay which ranged between 23°38.530'-38.740' N, 119°36.280'-36.560' E. The measurable area of sea pen was about 6.1ha, in which the population was between 0 to 27 m^(-2), and the mean density was 2.9 m^(-2). Sea pens were distributed around the low-tide line at spring tides. Sediment particles in sea pen habitats ranged from ”very coarse sand” to ”pebble,” and the sorting coefficient was between ”moderately sorted” and ”poorly sorted.” Higher density of sea pens were found out in poorly sorted pebble habitats.