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Bacterial Diversity And Function Within An Epigenic Cave System And Implications For Other Limestone Cave Systems, Kathleen Merritt Brannen-Donnelly

Doctoral Dissertations

There are approximately 48,000 known cave systems in the United States of America, with caves formed in carbonate karst terrains being the most common. Epigenic systems develop from the downward flow of meteoric water through carbonate bedrock and the solutional enlargement of interconnected subsurface conduits. Despite carbonate karst aquifers being globally extensive and important drinking water sources, microbial diversity and function are poorly understood compared to other Earth environments. After several decades of research, studies have shown that microorganisms in caves affect water quality, rates of carbonate dissolution and precipitation, and ecosystem nutrition through organic matter cycling. However, limited prior …

Cenozoic And Recent Lunulitiform Bryozoans Of The Gulf And Atlantic Coasts, Ronald Greeley

Doctoral Dissertations

"Free, cup-shaped colonies of cheilostomatous bryozoans, equipped with vibracula, are termed lunulitiform bryozoans. This group is found in sandy and calcareous Cenozoic deposits of the Gulf and Atlantic Coastal Plains. Cupuliform bryozoans are taxonomically distinct from, but in many ways similar to, lunulitiform bryozoans; the two groups are frequently found together.

Known lunulitiform genera of the Gulf and Atlantic Coastal Plains are diagnosed and their species described: Lunulites Lamarck, fifteen species, one new; Oligotresium Gabb and Horn, six species, two new; Discoporella d'Orbigny, two species; Cupuladria Canu and Bassler, two species; Selenaria Busk, one species; Otionella Canu and Bassler, four …