bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phosphorus and Ammonium Concentrations in Surface Runoff from Grasslands Fertilized with Broiler Litter
Authors: Pierson S. T. , Cabrera M. L. , Evanylo G. K. , Kuykendall H. A. , Hoveland C. S. , McCann M. A. , West L. T. 
Published: June 2010

ABSTRACTApplication of broiler (Gallus gallus domesticus) litter to grasslands can increase ammonium (NH4–N) and dissolved reactive phosphorus (DRP) concentrations in surface runoff, but it is not known for how long after a broiler litter application that these concentrations remain elevated. This long‐term study was conducted to measure NH4–N and DRP in surface runoff from grasslands fertilized with broiler litter. Six 0.75‐ha, fescue (Festuca arundinaceaSchreb.)–bermudagrass [Cynodon dactylon(L.) Pers.] paddocks received broiler litter applications in the spring and fall of 1995–1996 and only inorganic fertilizer N in the spring of 1997–1998. Surface runoff from each paddock was measured and analyzed for NH4–N and DRP. Broiler litter increased flow‐weighted NH4–N and DRP concentrations from background values of 0.5 and 0.4 mg L−1, respectively, to values > 18 mg L−1in a runoff event that took place immediately after the third application. Ammonium concentrations decreased rapidly after an application and were not strongly related to time after application or runoff volume. In contrast, DRP concentrations tended to decrease more slowly, reaching values near 1 mg L−1by 19 mo after the last application. Dissolved reactive P concentrations decreased linearly with the natural logarithm of days after application (p< 0.03), and increased linearly with the natural logarithm of runoff volume (p< 0.0001).
Pesticide Applications of Copper on Perennial Crops in California, 1993 to 1998
Authors: Epstein L. , Bassein S. 
Published: June 2010

ABSTRACTInorganic copper is used as a broad‐spectrum fungicide and bacteriocide on a variety of agricultural crops. After application, the copper residue typically accumulates in the upper 15 cm of soil. Data from the California Pesticide Use Reports were used to estimate the augmentation of copper in the soil that resulted from pesticide applications for the six years from 1993 to 1998 on 12 crops that are grown without rotation. The estimated mean mg Cu kg−1soil added to the upper 15 cm during the six years was the following: walnut (Juglans regiaL.), 28; peach [Prunus persica(L.) Batsch var.persica], 22; nectarine [Prunus persica(L.) Batsch var.nucipersica(Suckow) C.K. Schneid], 19; cherry (Pseudolmedia oxyphyllariaDonn. Sm.), 18; rice (Oryza sativaL.), 16; apricot (Prunus armeniacaL.), 11; orange [Citrus sinensis(L.) Osbeck] and plum (Prunus domesticaL. subsp.domestica), 9; lemon [Citrus limon(L.) Burm. f.] and almond [Prunus dulcis(Mill.) D.A. Webb], 6; pear (Pyrus communisL.), 4; and grape (Vitis viniferaL.), 3. In addition, for the first five of these crops, we estimated the area that was treated with each level of kg Cu ha−1For example, for walnut orchards, we estimated that 12500 ha, or 17% of the planted area, was treated with a quantity of Cu that would increase the total concentration of Cu in the upper 15 cm of soil by at least 50 mg Cu kg−1soil. A comparison of the amount of Cu per unit planted area that was applied in the first and second half of the study indicated that the intensity of copper use is either relatively constant or increasing, depending on the crop. The findings are discussed in relation to the potential effect of continued long‐term use of Cu pesticides on soil sustainability.
Zinc Accumulation by the Slime Mold Fuligo septica (L.) Wiggers in the Former Soviet Union and North Korea
Authors: Zhulidov Daniel A. , Robarts Richard D. , Zhulidov Alexander V. , Zhulidova Olga V. , Markelov Danila A. , Rusanov Viktor A. , Headley John V. 
Published: June 2010

ABSTRACTSamples of the slime mold Fuligo septica (L.) Wiggers were collected from an ecologically diverse selection of sites across the former USSR and in North Korea to determine their Zn concentrations. Plasmodia were collected from trees, rocks, soils, the walls of buildings and a variety of other materials and structures from 1990 to 1996. The biomass collected ranged from 305 to 968 mg, whereas Zn concentrations in plasmodia of F. septica ranged from 8400 to 23000 mg kg−1 dry wt. (mean and standard error = 14200 ± 860 mg kg−1 dry wt.). No clear trend as to which areas produced F. septica with the highest Zn concentrations was discernable. Nor was it possible to identify any particular substrate on which F. septica grew that produced noticeably high Zn concentrations. For example, forest litter on which F. septica was found had Zn concentrations of only 25 to 130 mg kg−1 dry wt. Our data confirm the only other study showing hyperaccumulation of Zn in F. septica, which was carried out in Finland. This ability seems to be unique to this species, but how or why it does this, or why such high Zn concentrations are not toxic to F. septica, are questions requiring future research.
Nitrous Oxide Emissions from an Ultisol of the Humid Tropics under Maize–Groundnut Rotation
Authors: Khalil M.I. , Rosenani A.B. , Van Cleemput O. , Fauziah C.I. , Shamshuddin J. 
Published: June 2010

ABSTRACTNitrous oxide (N2O) contributes to global climate change and agricultural soils seem to be the major source. Lack of information led to this study on the influence of different amounts and sources of nitrogen on N2O emission from a maize (Zea maysL.)–groundnut (Arachis hypogaeL.) crop rotation in an Ultisol of the humid tropics. The treatments were: inorganic N + crop residues (NC), inorganic N only (RN), and half of inorganic N + crop residues + chicken manure (NCM). The corresponding amount of N applied was 322, 180, and 400 kg ha−1yr−1, respectively. The N2O emissions depended on the amounts and types of N. A maximum peak (9889 ± 2106 μg N2O‐N m−2d−1) was detected at 2 wk before maize sowing amended with chicken manure, showing a persistent influence on N transformations and N2O release. The mineral N from either applied source became low by 2 to 4 wk, coinciding with the small N2O fluxes or its consumption to a few isolated instances. The N2O flux significantly correlated with the mineral N and water‐filled pore spaces. The direct annual N2O emission was 3.94 ± 0.23, 1.90 ± 0.08, and 1.41 ± 0.07 kg N2O‐N ha−1from the NCM, NC, and RN treatments, respectively. The corresponding N2O‐N loss of the applied N plus N fixed by groundnut was 0.83, 0.49, and 0.59%. Overestimations of direct annual N2O emission using the Intergovernmental Panel on Climate Change (IPCC) methodology suggest a location‐specific emission factor for variable N sources to be considered.
Site‐Specific Phosphorus Application Based on the Kriging Fertilizer‐Phosphorus Availability Index of Soils
Authors: Juang Kai‐Wei , Liou Day‐Chyng , Lee Dar‐Yuan 
Published: June 2010

ABSTRACTSite‐specific phosphorus management is done to optimize crop production and minimize P loss from soils. The spatial variability of the available P prior to fertilizer application and the P‐fixation tendency of soil both need to be taken into account for variable‐rate P application. The objectives of this research were to document the spatial variability of the fertilizer‐P availability index, which shows the P‐fixation tendency, and to develop a strategy that takes the spatial distribution of this index into account for site‐specific phosphorus application. In this study, the spatial patterns of the fertilizer‐P availability index were characterized by using geostatistics. The ordinary kriging was used for spatial interpolation of the fertilizer‐P availability index. Because the fertilizer‐P availability index of soil is related to oxalate‐extractable Fe and Al and because measuring oxalate‐extractable Fe and Al is much easier than directly determining the fertilizer‐P availability index, the spatial distribution of the fertilizer‐P availability index can be obtained using the oxalate‐extractable Fe and Al data. The spatial distribution of Olsen‐extractable P, which was used to measure the available‐P status prior to fertilizer‐P application, was also estimated by using ordinary kriging. The required fertilizer‐P amounts were then determined using the kriging estimates of the fertilizer‐P availability index and Olsen‐extractable P. A fertilizer‐P recommendation map for the 430‐ha study site in Changhua county, Taiwan was generated by using this approach for illustration. The proposed method for generating fertilizer‐P recommendation maps can be used for variable‐rate application to maintain an adequate P status for crop production and to potentially reduce the P loss from soils.
Effect of Mixing Soil Aggregates on the Phosphorus Concentration in Surface Waters
Authors: Maguire R.O. , Edwards A.C. , Sims J.T. , Kleinman P.J.A. , Sharpley A.N. 
Published: June 2010

ABSTRACTAt any time, the phosphorus (P) concentration in surface waters is determined by a complex interaction of inputs of soluble P and sorption–desorption reactions of P with sediments. This study investigated what factors control P in solution when various soil aggregates were mixed, seen as being analogous to selective soil erosion events, transport, and mixing within river systems. Fifteen soils with widely differing properties were each separated into three aggregate size fractions (2–52 μm, 53–150 μm, and 151–2000 μm). Resin P, water‐soluble phosphorus (WSP), and the phosphorus buffer capacity (PBC = resin P/WSP) were measured for each aggregate size fraction and WSP was also measured for 11 mixes of the aggregate fractions. The smallest aggregates tended to be enriched with resin P relative to the larger aggregates and the whole soils, while the opposite was true for WSP. As the PBC was a function of resin P and WSP, the PBC was greatest in the 2‐ to 52‐μm aggregate size fraction in most cases. When two aggregate size fractions were mixed, the measured WSP was always lower than the predicted WSP (i.e., the average of the WSP in the two individual aggregates), indicating that WSP released by one aggregate fraction could be resorbed by another aggregate fraction. This resorption of P may result in lower than expected solution P concentration in some surface waters. The strength with which an eroded aggregate can release or resorb P to or from solution is in part determined by that aggregate's PBC.
Evaluation of Leachate Recirculation on Nitrous Oxide Production in the Likang Landfill, China
Authors: Lee Chun Man , Lin Xue Rui , Lan Chong Yu , Lo Samuel Chun Lap , Chan Gilbert Yuk Sing 
Published: June 2010

ABSTRACTLandfill leachate recirculation is efficient in reducing the leachate quantity handled by a leachate treatment plant. However, after land application of leachate, nitrification and denitrification of the ammoniacal N becomes possible and the greenhouse gas nitrous oxide (N2O) is produced. Lack of information on the effects of leachate recirculation on N2O production led to a field study being conducted in the Likang Landfill (Guangzhou, China) where leachate recirculation had been practiced for 8 yr. Monthly productions and fluxes of N2O from leachate and soil were studied from June to November 2000. Environmental and chemical factors regulating N2O production were also accessed. An impermeable top liner was not used at this site; municipal solid waste was simply covered by inert soil and compacted by bulldozers. A high N2O emission rate (113 mg m−2h−1) was detected from a leachate pond purposely formed on topsoil within the landfill boundary after leachate irrigation. A high N2O level (1.09 μg L−1) was detected in a gas sample emitted from topsoil 1 m from the leachate pond. Nitrous oxide production from denitrification in leachate‐contaminated soil was at least 20 times higher than that from nitrification based on laboratory incubation studies. The N2O levels emitted from leachate ponds were compared with figures reported for different ecosystems and showed that the results of the present study were 68.7 to 88.6 times higher. Leachate recirculation can be a cost‐effective operation in reducing the volume of leachate to be treated in landfill. However, to reduce N2O flux, leachate should be applied to underground soil rather than being irrigated and allowed to flow on topsoil.
Soil and Plant Selenium at a Reclaimed Uranium Mine
Authors: Sharmasarkar Shankar , Vance George F. 
Published: June 2010

ABSTRACTSelenium (Se) associated with reclaimed uranium (U) mine lands may result in increased food chain transfer and water contamination. To assess post‐reclamation bioavailability of Se at a U mine site in southeastern Wyoming, we studied soil Se distribution, dissolution, speciation, and sorption characteristics and plant Se accumulation. Phosphate‐extractable soil Se exceeded the critical limit of 0.5 mg/kg in all the samples, whereas total soil Se ranged from a low (0.6 mg/kg) to an extremely high (26 mg/kg) value. Selenite was the dominant species in phosphate and ammonium bicarbonate‐diethylenetriamine pentaacetic acid (AB‐DTPA) extracts, whereas selenate was the major Se species in hot water extracts. Extractable soil Se concentrations were in the order of KH2PO4 > AB‐DTPA > hot water > saturated paste. The soils were undersaturated with respect to various Se solid phases, albeit with high levels of extractable Se surpassing the critical limit. Calcium and Mg minerals were the potential primary solids controlling Se dissolution, with dissolved organic carbon in the equilibrium solutions resulting in enhanced Se availability. Adsorption was a significant (r2 = 0.76–0.99 at P < 0.05) mechanism governing Se availability and was best described by the initial mass isotherm model, which predicted a maximum reserve Se pool corresponding to 87% of the phosphate‐extractable Se concentrations. Grasses, forbs, and shrubs accumulated 11 to 1800 mg Se/kg dry weight. While elevated levels of bioavailable Se may be potentially toxic, the plants accumulating high Se may be used for phytoremediation, or the palatable forage species may be used as animal feed supplements in Se‐deficient areas.
Relationships between Bacterial Tolerance Levels and Forms of Copper and Zinc in Soils
Authors: Saeki K. , Kunito T. , Oyaizu H. , Matsumoto S. 
Published: June 2010

ABSTRACTThe effects of various fractions of copper (Cu) and zinc (Zn) on soil bacteria were evaluated by the heavy metal tolerance level of the bacterial community (IC50) in soil samples collected near a mine. The IC50values had no relationship with the total concentrations of Zn and Cu in the soils, but were weakly correlated with the 0.05MCaCl2–extractable form of each metal in the soils (Cu:R2= 0.670,p< 0.01; Zn:R2= 0.453,p< 0.05). It was found that the IC50correlated strongly with the total concentration of each metal in the extracts from water‐saturated soil samples, described below as “soil solution” (Cu:R2= 0.789,p< 0.01; Zn:R2= 0.617,p< 0.01). The speciation of these metals in the soil solutions was estimated using an equilibrium thermodynamic computer model, SOILCHEM. Simulated free Cu ion ranged from 18 to 98% of total Cu, and organic complexes of Cu ranged from <1 to 56%. In all samples, Zn existing as the free ion was estimated to be more than 80% of total Zn in the soil solutions. The IC50values were also correlated with the estimated free metal ion activities, but with slightly lower correlation coefficients than found for total concentration in the soil solutions (Cu:R2= 0.735,p< 0.01; Zn:R2= 0.610,p< 0.01). The results suggest that not only high metal ion activities, but also total dissolved metal concentrations in soil solutions may affect the bacterial community.
Soil Testing to Predict Phosphorus Leaching
Authors: Maguire Rory O. , Sims J. Thomas 
Published: June 2010

ABSTRACTSubsurface pathways can play an important role in agricultural phosphorus (P) losses that can decrease surface water quality. This study evaluated agronomic and environmental soil tests for predicting P losses in water leaching from undisturbed soils. Intact soil columns were collected for five soil types that had a wide range in soil test P. The columns were leached with deionized water, the leachate analyzed for dissolved reactive phosphorus (DRP), and the soils analyzed for water‐soluble phosphorus (WSP), 0.01 M CaCl2 P (CaCl2–P), iron‐strip phosphorus (FeO‐P), and Mehlich‐1 and Mehlich‐3 extractable P, Al, and Fe. The Mehlich‐3 P saturation ratio (M3‐PSR) was calculated as the molar ratio of Mehlich‐3 extractable P/[Al + Fe]. Leachate DRP was frequently above concentrations associated with eutrophication. For the relationship between DRP in leachate and all of the soil tests used, a change point was determined, below which leachate DRP increased slowly per unit increase in soil test P, and above which leachate DRP increased rapidly. Environmental soil tests (WSP, CaCl2–P, and FeO‐P) were slightly better at predicting leachate DRP than agronomic soil tests (Mehlich‐1 P, Mehlich‐3 P, and the M3‐PSR), although the M3‐PSR was as good as the environmental soil tests if two outliers were omitted. Our results support the development of Mehlich‐3 P and M3‐PSR categories for profitable agriculture and environmental protection; however, to most accurately characterize the risk of P loss from soil to water by leaching, soil P testing must be fully integrated with other site properties and P management practices.
Soil‐to‐Root Transfer and Translocation of Polycyclic Aromatic Hydrocarbons by Vegetables Grown on Industrial Contaminated Soils
Authors: Fismes Joëlle , Perrin‐Ganier Corinne , Empereur‐Bissonnet Pascal , Morel Jean Louis 
Published: June 2010

ABSTRACTPolycyclic aromatic hydrocarbons (PAHs) are possible contaminants in some former industrial sites, representing a potential risk to human health if these sites are converted to residential areas. This work was conducted to determine whether PAHs present in contaminated soils are transferred to edible parts of selected vegetables. Soils were sampled from a former gasworks and a private garden, exhibiting a range of PAH concentrations (4 to 53 to 172 to 1263 and 2526 mg PAHs kg−1 of dry soil), and pot experiments were conducted in a greenhouse with lettuce (Lactuca sativa L. var. Reine de Mai), potato (Solanum tuberosum L. var. Belle de Fontenay), and carrot (Daucus carota L. var. Nantaise). At harvest, above‐ and belowground biomass were determined and the PAH concentrations in soil were measured. In parallel, plates were placed in the greenhouse to estimate the average PAH‐dust deposition. Results showed that the presence of PAHs in soils had no detrimental effect on plant growth. Polycyclic aromatic hydrocarbons were detected in all plants grown in contaminated soils. However, their concentration was low compared with the initial soil concentration, and the bioconcentration factors were low (i.e., ranging from 13.4 × 10−4 in potato and carrot pulp to 2 × 10−2 in potato and carrot leaves). Except in peeled potatoes, the PAH concentration in vegetables increased with the PAH concentration in soils. The PAH distribution profiles in plant tissues and in soils suggested that root uptake was the main pathway for high molecular weight PAHs. On the opposite, lower molecular weight PAHs were probably taken up from the atmosphere through the leaves as well as by roots.
Arsenic Accumulation in the Hyperaccumulator Chinese Brake and Its Utilization Potential for Phytoremediation
Authors: Tu Cong , Ma Lena Q. , Bondada Bhaskar 
Published: June 2010

ABSTRACTThe unique property of arsenic hyperaccumulation by the newly discovered Chinese brake (Pteris vittata L.) fern is of great significance in the phytoremediation of arsenic‐contaminated soils. The objectives of this study were to (i) examine arsenic accumulation characterized by its distribution pattern in Chinese brake, and (ii) assess the phytoextraction potential of the plant. Young ferns with five or six fronds were transferred to an arsenic‐contaminated soil containing 98 mg As kg−1 and grown for 20 wk in a greenhouse. At harvest, the Chinese brake produced a total dry biomass of 18 g plant−1 Arsenic concentration in the fronds was 6000 mg kg−1 dry mass after 8 wk of transplanting, and it increased to 7230 mg kg−1 after 20 wk with a bioconcentration factor (ratio of plant arsenic concentration to water‐soluble arsenic in soil) of 1450 and a translocation factor (ratio of arsenic concentration in shoot to that in root) of 24. The arsenic concentrations increased as the fronds aged, with the old fronds accumulating as much as 13 800 mg As kg−1 Most (approximately 90%) of the arsenic taken up by the Chinese brake was transported to the fronds, with the lowest arsenic concentrations in roots. About 26% of the initial soil arsenic was removed by the plant after 20 wk of transplanting. Our data suggest that the arsenic hyperaccumulating property of the Chinese brake could be exploited on a large scale to remediate arsenic contaminated soils.
Export of Manure Phosphorus and Nitrogen in Turfgrass Sod
Authors: Vietor D. M. , Griffith E. N. , White R. H. , Provin T. L. , Muir J. P. , Read J. C. 
Published: June 2010

ABSTRACTRegulatory mandates have increased demand for best management practices (BMPs) that will reduce nutrient loading on watersheds impaired by excess manure P and N. Export of manure P and N in turfgrass sod harvests is one BMP under consideration. This study quantified amounts and percentages of P and N removed in a sod harvest for different rates of manure and inorganic P and N. Six treatments comprised an unfertilized control, two manure rates with and without supplemental inorganic N, and inorganic P and N only. The treatments were applied to ‘Tifway’ bermudagrass (Cynodon dactylonL. ×C. transvaalensisBurtt‐Davey), ‘609’ buffalograss [Buchloe dactyloides(Nutt.) Engelm.], and ‘Reveille’ bluegrass (Poa arachniferaTorr. ×P. pratensisL.) under field conditions. Comparisons among treatments revealed small variations of P and N content in clippings and the plant component of sod, but large variations in the soil component of sod for each turf species. In addition, 2 to 10 times more P and 1.3 to 5 times more N was removed in soil than in plant components of sod for the two manure rates with and without added inorganic N. Percentages of applied P and N in harvested sod were similar for the two manure rates with and without added N for each species, but differed among turf species for each P (46 to 77%) and N (36 to 47%). The large amounts and percentages of manure P and N removed by sod harvest support the feasibility of this BMP in efforts to reduce nutrient loads on watersheds.