Diatom species Cymbella stuxbergii
3181 of 3588

Diatom species Cymbella stuxbergii.

June 2, 2010
Diatom species Cymbella stuxbergii. Diatoms are a large group of microscopic algae that grow as single cells or small colonies. This sample was taken as part of a Mongolian-American international partnership to survey the diatom flora of Hovsgol National Park in north-central Mongolia. [One of 7 related images. See Next Image.]

More about this Image Dr. Mark B. Edlund is in the process of collecting, cataloging and preserving diatom specimens from a remote lake in north-central Mongolia. Diatoms are a large group of microscopic algae that grow as single cells or small colonies. They are an important part of the "primary producer" community in most aquatic habitats. They often live within narrow environmental conditions and can act as bioindicators for changes in pollution, water temperature, nutrient levels and salinity.

"Diatoms are incredibly valuable as a tool for water quality monitoring," Dr. Edlund explains. "And they are one of the primary tools used in paleoecology, a discipline that uses fossil organisms to decipher environmental history."

The recipient of a three-year postdoctoral National Science Foundation (NSF) International Research Fellow Award for his work on diatoms in Mongolia's Lake Hovsgol National Park, Dr. Edlund and his collaboration of American and Mongolian scientists have made over 600 collections of diatoms to date from Lake Hovsgol. They have established permanent herbarium collections at the National University of Mongolia and at the California Academy of Sciences, the University of Michigan and the Science Museum of Minnesota.

Dr. Edlund chose Lake Hovsgol and the surrounding region because it is one of the most pristine large lakes on Earth and therefore globally significant as a natural laboratory for the study of ecology and evolution. The lake is estimated to be over 1.6 million years old.

The last time a biotic survey of Lake Hovsgol was conducted was in 1903--nearly a century ago. The lack of extensive sampling led Dr. Edlund and his collaborators, Dr. Eugene Stoermer of the University of Michigan and Dr. Ts. Jamsran of Mongolian State University, to conclude that the biodiversity of diatoms in Lake Hovsgol was severely underestimated.

After viewing a number of microscope slides from the 1903 collection, initially made by a Russian zoologist, Dr. Edlund's team discovered that a number of species originally described were still alive and well in Lake Hovsgol. And a number of diatoms were endemic to that lake. He confirmed the results by taking a sediment core of material approximately 150 years old, and comparing it to recent samples. He found the same species complex existed in both the core samples and in the lake today.

Lake Hovsgol has been named Mongolia's first International Long-Term Ecological Research (ILTER) site. This text was taken from NSF Directorate for Social, Behavioral and Economic Sciences Nugget story"When is a Diatom like a Dodo Bird--Documenting Diversity in Mongolia's Lake Hovsgol."

comments powered by Disqus