Mineralogical and chemical analyses performed on 67 ferromanganese nodules from widely varying locations and depths within the marine environment indicate that the minor element composition is controlled by the mineralogy, and that the formation of the mineral phases is depth dependent.

No abstract

The ability of some halophytes to accumulate salts may make them helpful in remediating soil contaminated with produced water and drilling mud from oil and gas exploration and production. Three inland halophytes, Atriplex acanthocarpa (two accessions) and A. canescens, were grown in pot culture in salt-contaminated soil, soil contaminated with salt and hydrocarbons, and uncontaminated soil collected from a Webb Co., Texas, gas production site. Electrical conductivity and soluble sodium of the soil extract were determined prior to planting and re-analyzed following harvest. Total sodium content in mature leaves was determined following harvest. Mature plant survival for all species in all soils ranged from 90–100%. In the salt-contaminated soil, post-harvest electrical conductivity and soluble sodium were significantly lower in the planted soils than in the unplanted soil. For each accession, biomass and plant mortality were greatest in the salt-contaminated soil. In both contaminated soils, the local ecotype of A. acanthocarpa had the highest concentration of tissue sodium and produced the greatest decrease in both electrical conductivity and soluble sodium. Field studies are necessary to determine the effectiveness of in situ application.

Survival and growth of 0.3–0.9 g red drum Sciaenops ocellatus were measured for fish reared in water‐recirculating culture systems containing one of the following media: 6g/L diluted seawater; 1g/L diluted seawater; 1g/L diluted seawater with either 1 or 5g/L of additional salt. Salt was added as sodium chloride, calcium chloride, or magnesium sulfate. Mean survival over the 42‐d study period was 56.3%. The 5g/L sodium chloride treatment had the highest survival rate (80.0%) and the calcium chloride treatment had the lowest (26.7%). The biomass‐change rate for fish in the 5g/L calcium chloride treatment was significantly lower (P < 0.05) than for fish in the 5g/L sodium chloride, 1g/L sodium chloride, or 5g/L magnesium sulfate treatments. The latter three treatments gave biomass‐change rates that did not differ (P > 0.05) from those obtained in the 1 or 6g/L diluted seawater.