南麂列岛位于浙江省南部海面。南麂本岛(称大山)位于东经121°,北纬27°30′,离大陆36海里,岛屿岩礁罗列。全年平均表面水温20℃左右,最低水温10℃左右,最高达30℃,海水肥沃,终年水清,透明度平均2米以下,常年比重1.022～1.024,惟风浪较大。琼胶(Agar)是石花菜(Gelidium)、江篱(Gracilaria)等琼胶藻类中所提取的胶质 Nanji Islands is located in the southern part of Zhejiang Province. Nanji Island (called the mountain) is located 121 ° longitude, latitude 27 ° 30 ’, 36 nautical miles from the mainland, the island rock reefs listed. The annual average surface water temperature of about 20 ℃, the minimum water temperature of about 10 ℃, up to 30 ℃, the fertile sea water year-round clear, the average transparency below 2 meters, perennial proportion of 1.022 ~ 1.024, but the storm larger. Agar is a gum that is extracted from agar algae such as Gelidium, Gracilaria,