Primary Investigation on Plankton Distribution of Several Lakes and Reservoirs in Taiwan

Abstract

本篇乃就珊瑚潭、曾文水庫、明德水庫、日月潭和鯉魚潭五處作浮游生物相之初步調查之結果，實驗期間自68年11月至70年4月為止。一般說來浮游生物很貧乏，這些水域均為貧營養湖，珊瑚潭三次之調查中，分別以原生動物之Eudorina elegans，矽藻之Melosira granulata和原生動物之Difflugia corona為優勢種，但以Eudorina elegans出現較頻繁，曾文水庫以原生動物之Eudorina elegans，Ceratium hirundinella，綠藻之Pediastrum biwae為優勢種，珊瑚潭與曾文水庫可為貧腐水性之水域。明德水庫以綠藻之Closteriopsis longissima和原生動物之Dinobryon cylindricum為最多，日月潭較豐富，以原生動物之Dinobryon cylindricum和Ceratium hirundinella以及藍藻之Coelosphaerium kutzingianum較多，鯉魚潭則以綠藻之Westella botryoides及藍藻之Microcystis aeruginosa較多為其特徵。另外曾文水庫70年2月27日所作日夜間之垂直分佈調查中，以綠藻之Pediastrum biwae為最多，其晚間之族羣分佈較白天探集的略有向上昇的情形，原生動物之Ceratium hirundinella則明顯地有白天族羣上浮，晚上下降之情形，在節足動物中，除了Cyclops之無節幼蟲，某種橈腳類，Diaphanosoma brachyurum和Eodiptomus formosus的族羣在晚間均有明顯的上浮的情形；明德水庫與日月潭可為β-中腐水性之水域，而東部之鯉魚潭則可為α-中腐水性之水域。In Taiwan, there are about 30 lakes and reservoirs which are only utilized in hydroelectricty, irrigation and water supply. Recently, government tries to develope fisheries using these waters such as cage culture and fry delivery and permits private agencies to run aquaculture business. Yet, there is few information about biota data. Here, authors deal with the primary investigation of plankton in the Coral Lake, Tsengwen Reservoir, Min-Teh Reservoir, the Sun-Moon Lake and the Carp Pond in order to set up some available data. Experiments were carried out from Oct. 1979 to Apr. 1981. Protozoa Eudorina elegans, Difflugia corona and Bacillariophyta Melosira granulata are the abundant species in the Coral Lake. The abundant species found in Tsengwen Reservoir are Eudorina elegans and Ceratium hirundinella belonging to Prorozoa, and Elakatothrix gelatinosa and Pediastrum biwae belonging to Chlorophyta. Cyanophyta Closteriopsis longissima and Protozoa Dinobryon cylindricum are the dominant species in the Min-Teh Reservoir. The dominant species in the Sun-Moon Lake and the Carp Pond are Prorozoa Dinobryon cylindricum and Chlorophyta Westella botryoides respectively. After investigating vertical distribution at noon and night during a day, the dominant species is Chlorophyta Pediastrum biwae and it seems to move upward and downward slightly at night to 25 m-30 m and 10 m-15 m. The diurnal and nocturnal populations of Protozoa Ceratium hirundinella and Artohrpoda except nauplius of Cyclops are quite different. Eodiaptomus formosus, Diaphanosoma brachyurum and Bosmina longirostris belonging to Arthropoda aggregate on the surface water at night. But Ceratium hirundinella having the characteristics of photosynthesis floats on surface water during the day and sinks in the evening. All of these water except Carp Pond are oligotrophic. From the viewpoint of biology of polluted waters, the Coral Lake and Tsengwen Reservoir are considered to be oligosaprobic, Min-Teh Reservoir and the Sun-Moon Lake are considered to be β-mesosaprobic and the Carp Pond is considered to be α-mesosaprobic.