摘要
Antarctic continental lakes and ponds are among the most impoverished aquatic environments on earth but many of them support flourishing populations of cyanobacteria,eukaryotic algae,protozoans,and some multicellular animals.In this study,we present results of a microscopic analysis of cyanobacteria and eukaryotic algae from nine diverse types of Antarctic continental water bodies during one austral summer.The results supplement and enlarge our previous studies on the limnological characteristics of the epiglacial and supraglacial lakes and ponds in Dronning Maud Land,an area that has received little attention from limnologists.The taxon with highest frequency among the samples(n=79)was Mesotaenium cf.berggrenii,a eukaryotic Zygnematophyceae,which occurred in 82%of the samples with a maximum cell density of 68 cells·mL^(-1).The taxa with second and third highest frequency were the prokaryotes Gloeocapsopsis(60%)and Leptolyngbya(41%),followed by Chlamydomonas(34%)and Cyanothece(29%).The number of taxa varied between 7-21 among the lakes and ponds,being highest in a supraglacial lake,and lowest in an epiglacial lake.The results did not reveal any obvious correlation between the abundance of any taxa and the water chemistry,but water bodies with inorganic sediments had higher cell densities and biomasses than those without sediment.This suggests the importance of sediment in supporting biological diversity in these ultraoligotrophic lakes and ponds.
基金
supported by AF-NSFC mobility program from the Academy of Finland(Grant no.333170)
National Natural Science Foundation of China(Grant no.52211530038).