James R. Self

Anaerobic digestion of municipal solid waste : utility of process residues as a soil amendment

Tuna processing wastes (sludges high in fat, oil, and grease [FOG]) and municipal solid waste (MSW) generated on Tutuila Island, American Samoa, represent an ongoing disposal challenge. The biological conversion of the organic fraction of these wastes to useful products, including methane and fertilizer-grade residue, through anaerobic high-solids digestion is currently in scale-up development. The suitability of the anaerobic digestion residues as a soil amendment was evaluated through extensive chemical analysis and greenhouse studies using corn as an indicator crop. Additionally, native Samoan soil was used to evaluate the specific application rates for the compost. Experiments established that anaerobic residues increase crop yields in direct proportion to increases in the application rate. Additionally, nutrient saturation was not demonstrated within the range of application rates evaluated for the Samoan soil. Beyond nutrient supplementation, organic residue amendment to Samoan soil imparts enhanced water- and nutrient-binding capacities.

Induced micronutrient toxicity in Petunia hybrida

Abstract Plant micronutnent toxicity symptoms of petunia (Petunia hybrida) cv. Ultra Crimson Star were experimentally induced and characterized. Starting at the 3–4 true leaf stage, plants grown in peat‐lite mix in 11 cm pots were constantly fed for 5 weeks with fertilizer solutions containing 0.25, 0.5, 1, 2, 3, 4, 5, and 6 mM plus the control concentration of boron, copper, iron, manganese, molybdenum and zinc at pH 6.5. The control solution had 20 μM B, 0.5 μM Cu, 10 μM Fe, 10 μM Mn, 0.5 μM Mo, and 4 μM Zn. Foliar toxicity symptoms were produced when the nutrient solutions contained 0.5 mM (5.4 ppm) B, 0.5 mM (32 ppm) Cu, 0.5 mM (28 ppm) Mn, 0.25 mM (24 ppm) Mo, and 0.25 mM (16 ppm) Zn. Iron in the range of concentrations tested did not cause foliar toxicity. Reduction in dry matter yield was evident when 2 mM (22 ppm) B, 1 mM (64 ppm) Cu, 6 mM (335 ppm) Fe, 0.5 mM (28 ppm) Mn, 0.25 mM (24 ppm) Mo, and 0.5 mM (33 ppm) Zn were used in the fertilizer solution. Leaf chlorophyll contents decreased as Cu an...

Micronutrient toxicity in buffalograss

Abstract The growth responses of buffalograss [Buchloe dactyloides (Nutt.) Engelm.] to elevated micronutrient levels in the fertilizer solution were investigated. Seedling plants established in peat‐lite mix in 11‐cm (0.6 L) pots in the greenhouse were irrigated with solutions containing 0.5, 1, 2, 4, 6, 8, or 12 mM of boron (B), chlorine (Cl), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), or zinc (Zn). The control solution contained (in μM): 20 B, 0.5 Cu, 40 Fe, 10 Mn, 0.5 Mo, and 4 Zn. A standard macronutrient concentration was used for all treatment solutions. Boron and Mo induced visual toxicity symptoms more readily than other micronutrients. Boron toxicity was characterized by chlorosis often accompanied by bleached leaf tips, while Mo toxicity resulted in leaf necrosis. The lowest levels that induced visual foliar toxicity were 0.5 mM B, 2 mM Cu, 4 mM Fe, 6 mM Mn, 1 mM Mo, and 4 mM Zn. Chloride did not induce foliar abnormalities in the concentration range tested. Biomass yield was reduc...

Sodium bicarbonate‐DTPA test for macro‐and micronutrient elements in soils

Abstract Individual soil tests are used to assess plant nutrient element needs. Separate soil tests, however, are time consuming and costly. Our objective was to develop a 0.5M sodium bicarbonate (NaHCO3) soil phosphorus (P) test in combination with 0.005M diethylenetriaminepentaacetic acid (DTPA) so macronutrient dements: ammonium‐nitrogen (NH4‐N), nitrate‐nitrogen (NO3‐N), P, potassium (K), calcium (Ca), and magnesium (Mg); and micronutrients: iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) could be quantified in one extraction. The NaHCO3‐DTPA extracting solution is a combination of 0.5M NaHCO3 and 0.005M DTPA and has a pH of 7.60±0.05. Sodium in the solution enhances the NH4, K, Ca, and Mg extraction; bicarbonate (HCO3) is for P extraction; DTPA chelates Ca, Mg, and micronutrients; and the water is for NO3 extraction. Soil samples (0–15 cm depth) came from two sources. The first set was from 12 N x P dryland proso millet (Panicum miliaceum L.) experiments, conducted from 1985 through 1987 in eas...

Non-availability of metals from an urban landfill in Virginia

ABSTRACTA toxicological assessment of a landfill, located in the Fort Darling Unit of Richmond National Battlefield Park (RICH), Virginia, was conducted from 1989 to 1992. After using acute and chronic toxicity tests, and priority pollutant analysis on shipped samples of water and sediments collected from a small unnamed tributary to the James River, and water collected from four monitoring wells constructed into the landfill, it was concluded that toxic conditions to aquatic life did not exist. For acute tests conducted on tributary water and sediments, three species of traditionally used aquatic organisms (Ceriodaphnia dubia, Pimphales promalas, Hyalella azteca) and one plant species (Latuca sativa) were used. For chronic tests conducted on tributary water, Ceriodaphnia dubia was used. Priority pollutant analyses of tributary water and sediments and water from monitoring wells in the landfill also did not reveal organic or inorganic chemicals at hazardous levels although metal concentrations in sediment...

Determining Site-Specific Toxicity of Copper to Daphnids and Fishes in a Brown-Water Ecosystem

ABSTRACT We examined the influence that wetland brown water had on the toxicity of copper to aquatic species in Swamp Creek basin, Wisconsin. Copper was added to Swamp Creek water and to laboratory-prepared reconstituted water and tested for toxicity using daphnids (Ceriodaphnia dubia and Ceriodaphnia reticulate), larval fathead minnows (Pimephales promelas), and larval walleye (Stizostedion vitreum). The toxicities of copper in Swamp Creek water, which contained dissolved organic carbon (DOC), were significantly lower than in water with no DOC. Therefore in successive experiments. using cultured C. dubia as the test organism, we experimentally reduced DOC in Swamp Creek water. We established that increased concentrations of DOC and hardness increased the odds of survival of C. dubia in the presence of potentially lethal concentrations of copper. In the Swamp Creek watershed which contains brown water and in watersheds where DOC concentrations are substantial, DOC, and hardness could be the principal factors in developing site-specific criteria involving copper and perhaps other metals.

Comparison of extractable phosphorus from two sulfuric acid methods with the Mehlich phosphorus test number one

Abstract All mineral phosphates in soil dissolve more completely when HCl is mixed with H2SO4 than with the HCl alone. It was hypothesized that a new extracting solution of H2SO4 alone with the same ionic strength or the same acidity as the Mehlich P1 extractant would extract similar amounts of soil phosphorus (P) as the Mehlich P1 soil test. Thirty six acid soils from Alabama, Georgia, North Carolina, South Carolina, and Colorado were used in this study. These acid soils reflect wide ranges in parent materials, texture, pH, organic matter, and available soil P. They were analyzed for available soil P with the Mehlich P1 soil test and with the two H2SO4 methods: Method A has an extracting solution of same ionic strength (0.0875M) as the Mehlich P1 extractant, and Method B was an extracting solution of the same acidity (0.0375M) as the Mehlich P1 extractant. Correlations between the results of Mehlich P1 with Method A and Method B were 0.994 and 0.997, respectively. The measured test precision was <3.5% fo...