The Diatom Flora of Hall’s Cave, Kerr County, Texas
Publication Date: 2024/12/01
Publication Volume: Journal of Cave and Karst Science 86 #
Publication Keywords: Diatoms, Nitzschia palmida
ABSTRACT:
This paper presents the results of a study to identify the species and distribution of diatoms growing in various habitats and on different substrates in Hall’s Cave, a limestone cave located on the Edward’s Plateau in western Kerr County, central Texas, USA. A diverse diatom assemblage that includes at least seventeen taxa was found growing in low to very low light conditions in different parts of the cave interior and on the walls of the cave entrance. Many other species were found in low numbers and may have been transported into the cave. One diatom species, Nitzschia palmida Carter is dominant in many samples, and overall, is the most abundant diatom observed in this investigation. This is the first published occurrence of N. palmida in the Western Hemisphere. These diatoms, all found typically in wet or damp settings, have adapted to growing in the cave environment. Nine species were common in only one sample, a scraping of wet guano-rich sediment on the floor at the back of the cave. These diatoms either survived passage through the digestive system of bats or were transported to the back of the cave by other means. The abundance and diversity of diatoms in Hall’s Cave suggests that diatoms may have been living in the cave for as long as there has been adequate moisture, nutrients and light, making them potential proxies for paleoenvironmental studies.
SIMPLE LANGUAGE SUMMARY:
Scientists studied tiny plants called diatoms in Hall's Cave, a limestone cave in Texas. These diatoms are single-celled algae that usually grow in wet places. The researchers wanted to learn which types of diatoms live in the cave and how they survive in low light. They found 17 main kinds of diatoms growing on the walls, floors, and even in bat droppings. One type, Nitzschia palmida, had never been seen in the Americas before. The scientists discovered that these diatoms have adapted to the dark, damp conditions of the cave and may have been living there for a long time. They also think studying these diatoms could help us understand what the environment was like thousands of years ago.
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