Diatom herbarium upgrades archival equipment for long-term accessibility

The diatom herbarium, which is part of the University of Guam (UOG) Herbarium and the Guam Ecosystems Collaboratorium for Corals and Oceans (GECCO) Biorepository is getting new, archival labels in recognition of its permanent value as a repository of diatom samples from the Marianas. The GECCO Biorepository is a physical and cyber warehouse of records and images that is operated by the Guam NSF EPSCoR program, which is funded by the National Science Foundation.

Diatoms are microscopic single-celled algae found in oceans, lakes, and rivers.

“Diatoms produce two-fifths of the oxygen we breathe and are used as water quality indicators in freshwater studies,” said UOG Professor Emeritus of Biology Christopher Lobban. “But for the marine species to be useful as indicators, we first have to find out what species live here and under what conditions.” The collection is a legacy project that was started by Lobban in 1988 and includes samples collected in Guam, Yap, Chuuk, Pohnpei, Palau, and the Marshall Islands. The collection was paused for nearly two decades, but was rekindled in 2007 when new equipment, collaborators, and online access to old literature became available.

As the project grew, it became apparent that it needed to be curated as a collection for long-term accessibility. Once the self-sticking slide labels from its start in 1988 began to fall off from age, Lobban found best practices for museums and acquired archival paper, special adhesives, and custom templates to catalog 3,000 existing slides and label new slides.

“If the slides are to be useful in the future the labels need to stay on,” said Lobban. “The label indicates the sample number, which refers to the collecting information in the lab notebooks and database. Not knowing where and when the samples were collected significantly decreases their scientific value.” There are over 3,300 slides and 1,600 scanning electron microscope stubs, along with raw materials and remainders in the diatom herbarium, which is located in the Microscopy Teaching and Research Lab.

The list of cataloged materials has been entered into the Guam NSF EPSCoR Biorepository online database. A long-term project is underway to get all of the imaged specimens added along with their images. The online database can be accessed at https://specifyportal.uog.edu.

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