This study evaluated the influence of the shoot density of the shoal grass Halodule wrightii on the composition of the associated algal community, in rocky and sandy habitats on the coast of Ceará in northeastern Brazil. The phycological community included 18 species in 10 families, members of Rodophyta (72.2%), Chlorophyta (22.2%) and Phaeophyceae (5.5%). The largest proportion were epilithic ...

Studies were conducted to examine interrelationships between the heterotrophic and phototrophic populations within an epilithic community in the outlet stream of a high alpine lake. Levels of nitrates, phosphates, and total organic compounds in the lake were consistently near the lower limits of detectability. Microscopic examination of the community by phase-contrast light microscopy and scann...

Metal-oxidizing bacteria may play a key role in the submarine weathering of volcanic rocks and the formation of ferromanganese crusts. Putative fossil microbes encrusted in Mn oxide phases are commonly observed on volcanic glasses recovered from the deep ocean; however, no known Mn(II)-oxidizing bacteria have been directly identified or cultured from natural weathered basalts. To isolate epilit...

The toxicity of sediments collected from depositional and erosional substrates at two locations on the Cuyahoga River in northeastern Ohio was compared. Upstream and downstream locations from the Akron Water Pollution Control Station (Akron WPCS) were selected to evaluate effects of the Akron WPCS effluent on sediment toxicity. Seven-day Ceriodaphnia dubia bioassays were conducted on sediment e...