Eton E. Codling

Laboratory characterization of extractable phosphorus in poultry litter and poultry litter ash

One method for handling excess poultry litter (PL) is burning. Implementation of this practice would reduce the volume of PL available for land application while generating electricity. Poultry litter ash (PLA), the by-product of burning PL, contains high concentrations of P, calcium, potassium, and magnesium, which could be used as fertilizers. Sequential extraction of PL has shown that the largest fraction of inorganic P was water (H2O) soluble, which could contribute to eutrophication of surface H2O. However, the forms of P in PLA have not been determined. The objective was to compare the extractable fractions of PLA with those of PL. Poultry litter samples were collected from three poultry farms on the Maryland Eastern Shore, and a portion of each PL sample was ashed at 550°C. An additional sample of PLA was obtained from a pilot study conducted by the Maryland Department of Natural Resources in which PL was used as a fuel source in a wood-burning power plant. P fractions of the PL and PLA were determined with a modified Hedley fractionation technique. The effectiveness of extractants in removing inorganic P from PL was ranked, from highest to lowest, as H2O > HCl > sodium bicarbonate > sodium hydroxide, whereas from PLA, the ranking was HCl > sodium bicarbonate > sodium hydroxide = H2O. The average total inorganic P extracted from PL and PLA by H2O were 55% and 1.45%, respectively, and the averaged total inorganic P extracted by HCl (hydrochloric acid) fractions were 34% and 82% for PL and PLA, respectively. The low H2O-soluble inorganic P observed in the PLA suggests that fertilizers using PLA would be less of a H2O-pollutant problem than PL when used in pastures and range lands. However, further studies are needed to determine the recommended application rate for poultry PLA compared with PL for optimum crop growth without impairing H2O quality.

Eastern Gamagrass Uptake Of Lead And Arsenic From Lead Arsenate Contaminated Soil Amended With Lime And Phosphorus

Lead arsenate was used in orchards from the 1930s to the 1960s, causing orchard soils to be contaminated with lead and arsenic, which may become an environmental problem when these lands are used for other purposes. Because soil removal is expensive, one alternative is to use plants to remove lead and arsenic from these soils (phytoremediation). Eastern gamagrass [Tripsacum dactyloides (L.) L.] has an extensive root system and is being used for soil improvement. The objective of this study was to determine uptake of lead and arsenic by eastern gamagrass from lead arsenate-contaminated orchard soils. A noncontaminated soil from Maryland (Typic Paleudults) and orchard soils from Maryland (Oxyaquic Hapludults) and Washington (Aridic Haploxerolls) with total (Aqua Regia extraction) Pb levels of 15, 574, and 943 mg kg−1 and total As levels of 8, 113, and 194 mg kg−1, respectively, were used. These three soils were treated with calcium carbonate and potassium phosphate; after incubation for 2 weeks, eastern gamagrass seedlings were transplanted into the amended soils. There was a slight increase in eastern gamagrass dry matter yield with P application compared with the no-phosphorus treatments. Yields were significantly reduced on the Aridic Haploxerolls orchard soil, which had the lowest level of organic carbon and highest levels of Pb and As. There was a slight but insignificant increase in tissue arsenic concentration and a reduction in Pb for plants grown on lime- and P-mended soils. Uptake of Pb was related to soil Pb concentration. Shoot As was related to soil As concentration, but there was no significant difference in root As level between the orchard soils. Eastern gamagrass did not remove substantial amounts of Pb and As from the soils, making this species a poor candidate for phytoremediation of lead arsenate-contaminated soils.

Short‐Term Effect of Lime, Phosphorus, and Iron Amendments on Water‐Extractable Lead and Arsenic in Orchard Soils

Abstract Lead arsenate was extensively used to control insects in apple and plum orchards in the 1900s. Continuous use of lead arsenate resulted in elevated soil levels of lead (Pb) and arsenic (As). There are concerns that As and Pb will become solubilized upon a change in land use. In situ chemical stabilization practices, such as the use of phosphate‐phosphorus (P), have been investigated as a possible method for reducing the solubility, mobility, and potential toxicity of Pb and As in these soils. The objective of this study was to determine the effectiveness of calcium carbonate (lime), P, and iron (Fe) amendments in reducing the solubility of As and Pb in lead‐arsenate‐treated soils over time. Under controlled conditions, two orchard soils, Thurmont loam (Hapludults) and Burch loam (Haploxerolls), were amended with reagent‐grade calcium carbonate (CaCO3), iron hydroxide [Fe(OH)3], and potassium phosphate (KH2PO4) and incubated for 16 weeks at 26°C. The experimental results suggested that the inorganic P increased competitive sorption between H2PO4 − and dihydrogen arsenate (H2AsO4 −), resulting in greater desorption of As in both Thurmont and Burch soils. Therefore, addition of lime, potassium phosphate, and Fe to lead‐arsenate‐contaminated soils could increase the risk of loss of soluble As and Pb from surface soil and potentially increase these metal species in runoff and movement to groundwater.

Effects of Broiler Litter Management Practices on Phosphorus, Copper, Zinc, Manganese, and Arsenic Concentrations in Maryland Coastal Plain Soils

Abstract The objective of this research was to assess the long‐term effects of broiler litter applications on soil phosphorus (P), copper (Cu), zinc (Zn), manganese (Mn), and arsenic (As) concentrations in Chesapeake Bay watershed Coastal Plain soils. Litter and soil samples were collected from 10 farms with more than 40 years of broiler production and from wooded sites adjacent to fields and were analyzed for P and metal contents. Averaged over farms, total P and metal concentrations in the litter were 12.8 g kg−1 P and 332, 350, 334, and 2.93 mg kg−1 Cu, Zn, Mn, and As, respectively. Surface (0–15 cm) soil pH values were greater than (5.7–6.4) the 0‐ to 15‐cm depth at wooded sites (3.5–4.3). Surface soil Bray 1 P values (149–796 mg kg−1) in amended fields were greater than wooded sites (4.4–17 mg kg−1). The 1N nitric acid (HNO3)–extractable metal concentrations were higher in amended soils than in wooded areas and were 7.7–32, 5.7–26, 12.3–71, and 0.6–3.0 mg kg−1 for Cu, Zn, Mn, and As, respectively, compared to 0.76–14, 4.6–22, 1.6–70, and 0.14–0.59 mg kg−1 for the same metals, respectively, in wooded areas. Results from this study demonstrated that long‐term broiler litter applications have altered the chemical properties of the Coastal Plain soils of the Maryland Eastern Shore. Metal concentrations were low in the surface layer of amended fields and typically decreased with depth. Phosphorus additions rather than metals are most likely to contribute to the degradation of the Chesapeake Bay watershed.

Effect of Flooding Lead Arsenate–Contaminated Orchard Soil on Growth and Arsenic and Lead Accumulation in Rice

Lead arsenate has been used as pesticide. Flooding soils contaminated by lead arsenate could increase plant arsenic and lead and become a human health risk. The objective was to determine the effects of flooding of lead‐arsenate soils on rice grain yield and arsenic and lead accumulation. Bagstown and Chashmont soils with high levels of arsenic and lead were planted with rice in the greenhouse under flooded and nonflooded conditions. Flooding reduced grain yield and increased grain arsenic concentration on both soils. Grain lead decreased with flooding for the Bagstown soil but increased for the Chashmont. Arsenic and lead concentrations in the straw were more than in grain. Grain arsenic and lead levels observed would not be expected to become a human health risk. However, bioavailability studies are needed. The high arsenic and lead in the straw may indirectly become a human health risk because rice straw is used for livestock feed and bedding.

Potential pollutant sources in a Choptank River (USA) subwatershed and the influence of land use and watershed characteristics

Row-crop and poultry production have been implicated as sources of water pollution along the Choptank River, an estuary and tributary of the Chesapeake Bay. This study examined the effects of land use, subwatershed characteristics, and climatic conditions on the water quality parameters of a subwatershed in the Choptank River watershed. The catchments within the subwatershed were defined using advanced remotely-sensed data and current geographic information system processing techniques. Water and sediment samples were collected in May-October 2009 and April-June 2010 under mostly baseflow conditions and analyzed for select bacteria, nitrate-N, ammonium-N, total arsenic, total phosphorus (TP), orthophosphate (ortho-P), and particle-phase phosphorus (PP); n=96 for all analytes except for arsenic, n=136, and for bacteria, n=89 (aqueous) and 62 (sediment). Detections of Enterococci and Escherichia coli concentrations were ubiquitous in this subwatershed and showed no correlation to location or land use, however larger bacterial counts were observed shortly after precipitation. Nitrate-N concentrations were not correlated with agricultural lands, which may reflect the small change in percent agriculture and/or the similarity of agronomic practices and crops produced between catchments. Concentration data suggested that ammonia emission and possible deposition to surface waters occurred and that these processes may be influenced by local agronomic practices and climatic conditions. The negative correlation of PP and arsenic concentrations with percent forest was explained by the stronger signal of the head waters and overland flow of particulate phase analytes versus dissolved phase inputs from groundwater. Service roadways at some poultry production facilities were found to redirect runoff from the facilities to neighboring catchment areas, which affected water quality parameters. Results suggest that in this subwatershed, catchments with poultry production facilities are possible sources for arsenic and PP as compared to catchment areas where these facilities were not present.

Potential of Chitosan (Chemically Modified Chitin) for Extraction of Lead-Arsenate Contaminated Soils

ABSTRACT Arsenic, lead, and phosphorous contamination in soils represents a health risk. Chitosan (poly-N-acetyl glucosamine) inexpensive by-product derived from chitin has been used as a metals adsorbent. Objectives of this research were to evaluate the effectiveness of chitosan solution for arsenic, lead, and phosphorous extraction from lead-arsenate contaminated soils, and evaluate the effectiveness of protonated chitosan flakes (PCF) and ferric hydroxide chitosan beads (Fe(III)-CB) for water-soluble As removal from these soils. Percentage of arsenic, lead, and phosphorous removed from the soils by chitosan solution ranged from 0.96% to 17%, 1.80% to 31%, and 0.66% to 11%, respectively. Percentage of water-soluble arsenic removed by PCF and by Fe (III)-CB ranged from 12% to 47% and 36% to 77%, respectively. Averaged over soils, Fe (III)-CB removed slightly more arsenic (As) (42 mg kg−1) compared to Mehlich III (40 mg kg−1) extractant. Results indicate potential for the use of chitosan as an extraction for lead-arsenate contaminated soils.

Broiler Litter Ash and Flue Gas Desulfurization Gypsum Effects on Peanut Yield and Uptake of Nutrients

Peanut (Arachis hypogaea L.) requires calcium (Ca) and phosphorus (P). Flue gas desulfurization gypsum (FGDG) and broiler litter ash (BLA) could be used as Ca and P fertilizer for peanuts. A pot study was conducted to determine the effects of BLA and FGDG on peanut yield and nutrient uptake compared to superphosphate (SP). Peanut kernel yields were 13.5 greater with BLA compared to SP. Kernel Ca concentration was 29% and P was 17% lower in in plants grown on the BLA compared to SP. Because of the high Ca content of the amended soil no significant difference was observed when FGDG was added. Micronutrients in kernel fertilized with BLA and FGDG were similar to superphosphate. The small difference in kernel Ca and P and the low levels of metals in the tissue between the BLA and SP demonstrate that BLA could be used as P source for peanuts.

Effects of Distance and Depth on Total and Bioaccessible Lead Concentrations in Soils from Two Farmhouses in Beltsville, Maryland

Movement of soil lead (Pb) has been studied, but Pb bioaccessiblity as a function of distance and depth from houses with histories of lead paint use needs to be investigated. This study investigated the effect of distance and depth on total and bioaccessible Pb near two houses with histories of lead paint use. Soil samples were collected at four distances and four depths. Total and bioaccessible Pb were extracted using 1 N ammonia nitrate and 0.4 m glycine, respectively. Bioaccessible Pb ranged from 27 to 886 mg kg−1 and from 187 to 4796 mg kg−1 for houses 1 and 2, respectively. Total and bioaccessible Pb concentrations were greatest at the 0.5 m distance and 2.5 cm depth for both houses. Percentage of total Pb that was bioaccessible at lower horizons was greater than or equal to that of the surface soil. Soil Pb reduction with increasing distance and depth makes it amenable to soil remediation.

Long-Term Effects of Fluidized Bed Combustion Material Applied at Disposal Levels on Soil Properties

This study was conducted to assess changes in soil properties of a soil that received a one-time application (360 Mg ha−1) of fluidized bed combustion material (FBCM) 23 years earlier. Soil samples were taken at three depths (0–10, 10–20, and 20–30 cm). Samples were also collected from an adjacent field with the same soil type for control. Hot nitric acid and Mehlich 3 extractions were used for total and extractable elements. Analyses indicated improvement in soil physical and chemical properties after 23 years of FBCM application. For example at the 20- to 30-cm depth, soil pH values increased from 4.9 to 7.7, whereas calcium concentrations increased from 0.23 to 1.52 g kg−1 with FBCM amendment. In most cases, metal concentrations were less with FBCM amendment. Results from this study demonstrated that soil physical and chemical improvements from FBCM were maintained even 23 years after an extremely high application of FBCM.