bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gaseous Nitrogen Emissions from Anaerobic Swine Lagoons: Ammonia, Nitrous Oxide, and Dinitrogen Gas
Authors: Harper Lowry A. , Sharpe Ron R. , Parkin Tim B. 
Published: July 2010

AbstractSeventy‐five percent of swine (Sus scrofa) production systems in North America use anaerobic or liquid‐slurry systems for waste holding or disposal. Accurate emissions data and emission factors are needed for engineering, planning, and regulatory agencies. These data are used for system design and evaluation of the effect of animal concentrations on the regional soil, surface and ground waters, and atmospheric environments. Noninvasive techniques were used to evaluate trace gases without disturbing the meteorology or lagoon system being measured. Micrometeorological and gas sensors were mounted on a submersible barge in the center of the lagoon for use with flux‐gradient methodology to determine trace gas fluxes, without disturbing atmospheric transport processes, over extended periods. Collateral measurements included lagoon nutrient, dissolved gas concentrations, and sludge gas mass flux. Ammonia emissions varied diurnally and seasonally and were highly correlated with windspeed and water temperature. Nutrient loading measurements showed that mobile ions, which were nonvolatile, were constant throughout four successive lagoons. Immobile ions concentrated primarily in the sludge layer of the first lagoon. Measurements of denitrification N2 losses suggest as much N2−N lost as from NH3‐N. Ammonia gas emissions are not as large a percentage of total nitrogen input to the lagoons as previously thought but unaccounted‐for nitrogen requires further research.
Simulation of Pesticide Persistence in the Field on the Basis of Laboratory Data—A Review
Authors: Beulke Sabine , Dubus Igor G. , Brown Colin D. , Gottesbüren Bernhard 
Published: July 2010

AbstractSimulations of pesticide fate in soils are often based on persistence models developed nearly 30 years ago. These models predict dissipation in the field on a daily basis by correcting laboratory degradation half‐lives for actual soil temperature and moisture content. They have been extensively applied, but to date no attempt has been made to evaluate existing studies in a consistent, quantitative way. This paper reviews 178 studies comparing pesticide soil residues measured in the field with those simulated by persistence models. The simulated percentage of initial pesticide concentration at the time of 50% measured loss was taken as a common criterion for model performance. The models showed an overall tendency to overestimate persistence. Simulated values ranged from 12 to 96% of initial pesticide concentrations with a median of 60%. Simulated soil residues overestimated the target value (50% of initial) by more than a factor of 1.25 in 44% of the cases. An underestimation by more than a factor of 1.25 was found in only 17% of the experiments. Discrepancies between simulated and observed data are attributed to difficulties in characterizing pesticide behavior under outdoor conditions using laboratory studies. These arise because of differences in soil conditions between the laboratory and the field and the spatial and temporal variability of degradation. Other possible causes include losses in the field by processes other than degradation, deviations of degradation from first‐order kinetics, discrepancies between simulated and actual soil temperature and moisture content, and the lack of soil‐specific degradation parameters. Implications for modeling of pesticide behavior within regulatory risk assessments are discussed.
Response of Four Turfgrass Cultivars to Limestone and Biosolids‐Compost Amendment of a Zinc and Cadmium Contaminated Soil at Palmerton, Pennsylvania
Authors: Li Yin‐Ming , Chaney Rufus L. , Siebielec Grzegorz , Kerschner Beverly A. 
Published: July 2010

AbstractRevegetation treatments (NPK fertilizer, limestone plus NPK fertilizer, or composted iron‐rich limed biosolids) were evaluated on severely Zn phytotoxic soils near a former smelter. Soils contained 15 500 mg Zn and 158 mg Cd kg−1 and initial soil pH was 6.0. Zinc‐resistant ‘Merlin’ red fescue (Festuca rubra L.) was compared with ‘Bonanza’ and ‘Kentucky‐31’ tall fescue (Festuca arundinacea Schreb.) and ‘Touchdown’ Kentucky bluegrass (Poa pratensis L.) for leaf phytotoxicity symptoms, rapidity of achieving cover, persistence of cover, and metal accumulation. Biosolids compost more strongly reduced soluble Zn and Cd, resulting in effective remediation of Zn phytotoxicity that persisted for the 4 yr of this test. ‘Merlin’ red fescue showed remarkable exclusion of Zn and Cd (201–446 mg kg−1 Zn and 0.9–2.7 mg kg−1 Cd in dry shoots from treated plots) but grew slowly and made poor lawns. ‘Kentucky‐31’ tall fescue plants grew rapidly and reached almost 100% cover within 3 mo in compost treatment plots, but the Zn exceeded phytotoxic threshold levels (>500 mg Zn kg−1). ‘Bonanza’ tall fescue and ‘Touchdown’ Kentucky bluegrass had good growth performance and contained lower concentrations of Zn and Cd than ‘Kentucky‐31’ tall fescue on biosolids‐compost amended treatments and were more suitable as a lawn and/or revegetation crop. After the first year of the study, the commercial turfgrasses survived only on the biosolids‐compost plots. The combination of calcareous soil pH and higher organic matter, Fe, and phosphate levels of biosolids‐compost amended plots improved the overall success of vegetation establishment and allowed important turfgrasses to revegetate highly Zn‐contaminated soils.
Phosphorus Forms in Manure and Compost and Their Release during Simulated Rainfall
Authors: Sharpley Andrew , Moyer Barton 
Published: July 2010

AbstractThe large accumulation of P in manure from animal feeding operations in localized areas has increased the potential for P export following land application. Impairment of freshwater quality by accelerated eutrophication has focused attention on manure management and the potential for P loss in runoff. Thus, we investigated the amounts and relative solubilities of P in manures and their composts using a modified Hedley fractionation and release of P during simulated rainfall (70 mm h−1 for 30 min) in laboratory columns (15‐cm diameter). Twenty‐four samples each of dairy manure, dairy manure compost, poultry manure, poultry manure compost, poultry litter, and swine manure were collected over 2 yr. Total P concentration ranged from 2600 to 40 000 mg kg−1, mostly as inorganic P (63 to 92%). The distribution of inorganic and organic P fractions depended on manure and compost type. Most of the inorganic P, 80%, was water extractable (2030 mg kg−1), while 55% was hydroxide extractable in swine slurry (16 620 mg kg−1) and 38% acid extractable in poultry manure (9320 mg kg−1). The dissolved inorganic P concentration in leachate from manure and compost (10 Mg ha−1 manure application rate) during 30‐rain rainfall ranged from 34 (poultry litter) to 75 mg L−1 (poultry manure). The amount of P leached by five simulated rainfall events was significantly correlated to respective water extractable inorganic (r2 = 0.98) or organic P (r2 = 0.99) of each material. This suggests that water extractable P may be used to estimate the potential for land‐applied manures or composts to enrich leachate and surface runoff P.
Evaluation of an Organic Semiconductor as a Sensor of Volatilized Herbicides
Authors: Álvarez‐Benedí J. , Souto J. , De Saja J. A. , Bolado S. 
Published: July 2010

AbstractThe use of a ytterbium bisphthalocyanine Langmuir‐Blodgett film sensor for the study of the volatilization of the herbicides imazamethabenz‐methyl, tri‐allate, and terbutryn is evaluated. The dynamic response of the sensor to the herbicides is analyzed using a model that relates the response of an isotropic sensor to the total immobilized amount of a particular herbicide, accounting for the diffusion through the sensor and the adsorption of each herbicide in the sensor's film. Three model parameters are analyzed in the response of the sensor to a pulse in the concentration of herbicide, analyzing separately the sorption and desorption stages: the response time (τ), the adsorption isotherm linearity (1/n), and the linearity of the variation of the electrical conductivity of the sensor with the amount of sorbed herbicide (B). In the sorption stage, τ ranged from 174 to 341 s, 1/n ranged from 0.57 to 1.04, and B was within the interval from 1.54 to 2.4. The desorption stage required a longer time to be accomplished and thus is less useful for practical purposes. The model parameters are compared with semiqualitative analysis of the response curves in the sorption stage and the capabilities of these sensors in qualitative and quantitative analysis of volatilized herbicides are discussed. Based on the differences in the model parameters, the sensors offered promising results for identification purposes. The results also suggest applications in quantitative analysis, although further improvements in the methodology are required for that purpose.
Pesticide Sorption by Low Organic Carbon Sediments: A Screening for Seven Herbicides
Authors: Madsen Lene , Lindhardt Bo , Rosenberg Per , Clausen Liselotte , Fabricius Ida 
Published: July 2010

AbstractThe sorption of seven pesticides in 10 Danish aquifer sediments has been studied. These sediments all have a total organic carbon (TOC) content below 1 g kg−1, and include carbonate‐bearing and carbonate‐free Quatenary sand deposits and a Cretaceous chalk aquifer. Batch experiments were carried out with metamitron, atrazine, isoproturon, mecoprop, 2,4‐D, bentazone, and metsulfuron‐methyl at an initial pesticide concentration of 0.25 mg L−1 in ground water. Generally, the sorption decreases in the order: metamitron, atrazine, isoproturon, mecoprop, 2,4‐D, metsulfuron‐methyl. The bentazone sorption was found to be insignificant. For a specific pesticide the sorption covers a range of Kd values (L kg−1) reflecting the different sediment characteristics. Multivariate regression analyses demonstrate that: (i) metamitron sorption is enhanced by increasing content of iron silicates; by contrast the oxalate extractable iron oxides have no influence on the metamitron sorption; (ii) sorption of atrazine, mecoprop, and 2,4‐D depends primarily on pH; the sorption is high at low pH (<6.7) compared with sorption at higher pH (>7.4); (iii) metsulfuron‐methyl only sorbs at pH below 5; and (iv) isoproturon sorption is primarily influenced by the specific surface area (SSA) and TOC. The present results illustrate the importance of choosing sediments of different geological origin in order to describe the influence of sediment properties on pesticide sorption.
Integrated Fertilizer and Irrigation Management to Reduce Nitrate Leaching in Central Spain
Authors: Diez J. A. , Caballero R. , Roman R. , Tarquis A. , Cartagena M. C. , Vallejo A. 
Published: July 2010

AbstractCropping systems that fail to manage N and irrigation, with the objective of reducing losses of N, are frequently associated with elevated concentrations of nitrate N in soil and ground water. A long‐term (4‐yr) field experiment was carried out at La Poveda Field Station (30 km southeast of Madrid, Spain) with the objective of assessing whether the effect of traditional cultivation practices (irrigation and fertilization) can be reduced. The experiment was conducted on a Typic Xerofluvent soil and a crop sequence (corn‐wheat‐corn‐oat) traditional in the area. Four fertilizer treatments (unfertilized check, urea, floranid [a slow‐release N fertilizer] and municipal organic waste [MOW] compost) were combined with two irrigation schedules (traditional and improved) in two sets of 24 plots. Seasonal drainage was estimated by the zero flux plane‐water balance equation and nitrate concentration was measured at the soil depth of deep percolation (1.4 m) by ceramic cup extraction system. Nitrate leaching could be attributed to both irrigation schedule and fertilizer type. Within fertilizer treatments, reductions of nitrate losses between irrigation schedules of 52, 51, 66, and 81% were found for the unfertilized check, urea, floranid, and MOW compost, respectively. Grain yields in the whole crop sequence were not affected by fertilizer or irrigation managements.
Herbicide Banding and Tillage Effects on Runoff, Sediment, and Phosphorus Losses
Authors: Hansen N. C. , Gupta S. C. , Moncrief J. F. 
Published: July 2010

AbstractTillage and weed control methods affect hydrology by altering soil surface conditions. The objective of this study was to assess the effects of herbicide banding with interrow cultivation on runoff, sediment, and phosphorus (P) losses for three different tillage systems. Tillage treatments were moldboard‐ or chisel plow‐based and ridge tillage. Tillage direction was up and down the slope of runoff plots and corn (Zea mays L.) was grown for two years. The herbicides alachlor [2‐chloro‐2′‐6′‐diethyl‐N‐(methoxymethyl)‐acetanilide] and cyanazine [2‐[ [4‐chloro‐6‐(ethylamino)‐1,3,5‐triazin‐2‐yl]amino‐2‐methylproprionitrile] were applied as a preemergent mixture by either broadcasting or banding. All treatments were mechanically cultivated one time. The effects of tillage practice and herbicide application method on runoff water quality were different before and after cultivation. Prior to cultivation, crop residue associated with the ridge till and chisel plow systems reduced runoff, sediment, and P losses compared with the moldboard plow system. Soil cover from weed growth between herbicide treated bands resulted in lower precultivation runoff, sediment, and P losses than broadcast treated plots, especially in the moldboard plow system. For runoff events occurring after cultivation, there were no differences among tillage practices or herbicide application methods on sediment or P losses. Weed cover between herbicide treated bands is effective in reducing runoff and contaminant losses in tillage systems with little existing crop residue and during the period when crop canopy is minimal. There was no yield loss associated with applying herbicides in a band compared with broadcasting.
An Agri‐Environmental Phosphorus Saturation Index for Acid Coarse‐Textured Soils
Authors: Khiari L. , Parent L. E. , Pellerin A. , Alimi A. R. A. , Tremblay C. , Simard R. R. , Fortin J. 
Published: July 2010

AbstractPotato (Solanum tuberosum L.) is a high P demanding crop contributing to P saturation of acid coarse‐textured soils. The P status is commonly assessed agronomically by soil testing of P (STP) and environmentally by soil P saturation or P solubility indexes. The aim of this work was to develop a P fertilizer recommendation model integrating P environmental risk and crop response probability, using P and Al extracted by the Mehlich‐III soil testing method (mg P or Al L−1 of soil) and expressed as (P/Al)M‐III percentage. The environmentally critical (P/Al)M‐III percentage was 15%, corresponding to the critical degree of phosphate saturation (DPS) value of 25% (oxalate extraction procedure) proposed in the Netherlands. Using the Cate‐Nelson procedure, the critical (P/Al)M‐III percentage across 78 field experiments was 8.2% as determined by inductively coupled‐argon plasma (ICP). Probability of potato response to P was close to 100% even above the critical STP values as shown by power tests on relative yields. The P recommendation model was computed from conditional expectations of 50 and 80% within each fertility group below 15% as (P/Al)M‐III. Above 15%, the model recommended 21 kg P ha−1, the amount of P exported by a tuber harvest of approximately 42 Mg ha−1. Using conversion equations with 114 soil samples for STP methods, fertility groups built for Quebec acid coarse‐textured soils were found to be comparable with those currently used in the Netherlands and Lower Saxony (Germany). The (P/Al)M‐III percentage provided a reliable and unifying criterion for making environmentally acceptable and agronomically efficient P recommendations for sustainable potato production.
Chemical Monitoring of Sewage Sludge in Pennsylvania: Variability and Application Uncertainty
Authors: Stehouwer Richard C. , Wolf Ann M. , Doty Willie T. 
Published: July 2010

AbstractApplication of sewage sludge to farmland in Pennsylvania (PA) is regulated by crop N needs and the cumulative loading of eight trace elements. A survey of 7746 sewage sludges produced at 177 publicly owned (wastewater) treatment works (POTWs) in PA from 1978 to 1997 was conducted to determine what changes have occurred in nutrient and trace element concentrations, how currently produced sewage sludges compare with regulatory trace element standards, inter‐ and intra‐POTW variability in sewage sludge constituents, and uncertainty estimates for application of nutrients and trace elements. Concentration medians and ranges of nutrients changed very little during the 20‐yr period, whereas there were large decreases in Cd, Cr, Cu, Pb, Hg, Ni, and Zn. Rates of decrease for concentrations of these elements and As, Se, and Mo were smaller or not different from zero in the last 5 yr of the survey. Assessment of sewage sludge constituents among a subset of 12 POTWs showed larger inter‐ than intra‐POTW variability. Sewage sludge N content uncertainty showed that the maximum error in determination of plant available N ranged from 0.39 to 1.09 of the intended amount. This uncertainty could be reduced by increased frequency of N analysis prior to sewage sludge application. Application uncertainty for trace elements was large relative to the amount of trace elements added to the soil in a single application, but very small relative to the cumulative loading limit (generally <0.01). Further decreases in trace element variability or increased frequency of analysis would not be expected to decrease error in trace element cumulative loading calculations.
Dissolved Organic Carbon and Methane Emissions from a Rice Paddy Fertilized with Ammonium and Nitrate
Authors: Lu Yahai , Wassmann Reiner , Neue Heinz‐Ulrich , Huang Changyong 
Published: July 2010

AbstractThe effect of nitrogen fertilizers on methane (CH4) production and emission in wetland rice (Oryza sativa L.) is not clearly understood. Greenhouse pot and laboratory incubation were conducted to determine whether the effect of N type (NH4‐N and NO3‐N) and rate (30 and 120 kg N ha−1) was related to the availability of carbon for CH4 production in flooded rice soils. In addition to CH4 emission rates, seasonal patterns of dissolved organic carbon (DOC) and dissolved CH4 were determined in soil solutions of the root zone (soil surrounding rice roots) and the non‐root zone (soil outside the root zone). Dissolved organic C in the root zone increased with plant growth and reached a maximum (16 to 21 mmol C L−1) at 1 wk after flowering, whereas DOC in the non‐root zone remained relatively low (1 to 5 mmol C L−1). The increase of dissolved CH4 concentrations was quicker and greater in the root zone (111 to 170 mol L−1) as compared with the non‐root zone (54 to 117 mol L−1). Methane emission increased from 0 to 1.0 mmol CH4 plant−1 d−1. From panicle initiation (PI) to maturation, the root zone DOC concentration was lower with NO3‐N application (8 to 13 mmol C L−1) than with NH4‐N (13 to 21 mmol CL−1). Similarly, NO3‐N application reduced dissolved CH4 concentration as well as CH4 emission. Anaerobic incubation showed that the inhibitory effect of NO3‐N addition on CH4 production lasted only 2 wk. Thus, the inhibitory effect of NO3‐N seemed not fully accountable for the prolonged reduction in CH4 production and emission in the fields. The root zone DOC that is enriched by plant‐borne C appears to be a main source for CH4 production and the lower DOC concentrations with NO3‐N application are accountable for the low CH4 emissions.
Mechanistic Modeling of Nitrite Accumulation and Nitrogen Oxide Gas Emissions during Nitrification
Authors: Venterea R. T. , Rolston D. E. 
Published: July 2010

AbstractNitrite (NO−2) accumulation in soil following nitrogen (N) fertilizer application has been observed under a variety of conditions. The presence of NO−2 together with soil acidity results in the formation of nitrous acid (HNO2), which decomposes abiotically to produce nitric oxide (NO) and nitrous oxide (N2O). These N oxide trace gases have potential effects on several atmospheric processes. Presented here is a model that describes some of the interactions between microbial, chemical, and physical processes that influence NO−2 accumulation and N oxide gas emissions following applications of NH+4‐based fertilizers. The model is applied to hypothetical and actual field scenarios. A two‐step, two‐population nitrification submodel is linked to gas production and transformation submodels. Transport of all chemical species occurs by diffusion. The model results suggest that some degree of transient nitrite accumulation following NH+4 application is a consequence of the nature of nitrification itself. Model simulations and sensitivity analysis indicate that (i) soils receiving similar fertilizer treatments but differing in their ability to buffer nitrification‐induced acidity may produce dramatically different N oxide gas emissions, (ii) subsurface fertilizer placement can significantly reduce net NO emissions, and (iii) the differential responses of Nitrosomonas and Nitrobacter populations to chemical toxicities associated with the form and/or rate of fertilizer application may significantly affect the extent of NO−2 accumulation and corresponding gas emissions. Overall, the results contribute to our basic understanding of how multiple microbial, chemical, and physical factors can interact to control the net soil‐to‐atmosphere emission of nitrification‐derived NO and N2O.
Native Plant Restoration of Copper Mine Tailings: II. Field Survival, Growth, and Nutrient Uptake
Authors: Kramer P. A. , Zabowski D. , Scherer G. , Everett R. L. 
Published: July 2010

AbstractCopper mine tailings are difficult to revegetate due to nutrient deficiencies, high acidity, and metal toxicities. Despite these poor substrate properties, native species may be preferred for restoration for ecological and economic reasons, as they may require less long‐term maintenance. In this study, amended and unamended mine tailings are contrasted with a natural soil and gravel for factors potentially limiting to growth. Twelve individuals of five native species (big‐leaf maple, western yarrow, Sitka alder, pearly everlasting, and fireweed) were grown in five different field plots. Plots consisted of: (i) copper mine tailings, (ii) natural soil, (iii) 15 cm of gravel over tailings, (iv) biosolids plus wood chips with 15 cm gravel over tailings, and (v) gravel. Survival was highly variable by species and plot type, with highest survival among all species with pearly everlasting, and highest survival by treatment with the natural soil and biosolids plus wood chips with gravel over tailings. Treatments resulted in a significant difference (p = 0.05) in species biomass production, with the biosolids resulting in highest biomass in all species except big‐leaf maple. Plant nutrient content was also higher with the biosolids. The tailings were extremely acidic and had high exchangeable AI. Sitka alder was most tolerant of the tailings, despite high AI uptake, and was productive across all plot types, possibly due to its tolerance of metals and high nutrient use efficiency. Both Sitka alder and pearly everlasting show promise for revegetating copper mine tailings, although with a biosolids and gravel amendment other native species may do equally well.