Soil algae from a Maryland serpentine formation

Algae from serpentine soil samples collected at Soldiers Delight, Maryland (located in the west central portion of Baltimore County) were cultured using an enrichment technique. The algal flora was found to consist of members of the Cyanophyta, Chlorophyta and Chrysophyta (Bacillariophyceae). Composition of the soil flora at the division level is similar to that of more favorable soil types, indicating possible adaptations to high chromium and nickel concentrations and a low Ca: Mg ratio. Among the Cyanophyceae examined were three genera known to contain species which fix N2. The presence of Cyanophyte genera capable of N2 fixation suggests possible N input to this generally nitrogen-poor system. Lack of nitrogenase activity in collections of blue-green algal mats during early spring may be due to seasonal variation or Mo deficiency common in serpentine soils.