bluuebunny/crossref_metadata_2025_split huggingface dataset:
Subcellular cadmium distribution, accumulation, and toxicity in a predatory gastropod,Thais clavigera, fed different prey
Authors: Cheung Ma-Shan , Fok Edmond M. W. , Ng Tania Y.-T. , Yen Yu-Fong , Wang Wen-Xiong 
Published: January 2006

AbstractBioaccumulation and toxicity of Cd were investigated in a marine predatory whelk, Thais clavigera, after being fed with the rock oyster, Saccostrea cucullata, or the herbivorous snail, Monodonta labio, for up to four weeks. The oysters and snails had different subcellular Cd distributions and concentrations in their bodies given their different metal-handling strategies and were exposed to dissolved Cd for two weeks before being fed to the whelks. After four weeks of dietary exposure, the Cd body concentrations in T. clavigera increased from 3.1 μg/g to between 22.9 and 41.8 μg/g and to between 22.7 and 24.1 μg/g when they were fed with oyster and snail prey, respectively. An increasing proportion of Cd was found to be distributed in the metallothionein (MT)-like proteins and organelle fractions, whereas the relative distribution in the metal-rich granules fraction decreased when the whelks were fed Cd-exposed prey. At the highest Cd dosage, more Cd was distributed in the pool of metal-rich granules when the whelks were fed the oysters than when they were fed the snails. Among all the biomarkers measured (MT induction, condition index, lipid peroxidation, and total energy reserve including carbohydrate, lipid, and protein), only MT showed a significant difference from the control treatments, and MT was the most sensitive biomarker for dietary Cd exposure. No toxicity was found in the whelks fed different Cd-exposed prey as revealed by various biomarkers at the different biological levels. Our results imply that metal fractionation in prey can alter the subsequent subcellular metal distribution in predators and that dietary Cd toxicity to the whelks was low, even when the accumulated Cd body concentrations were high.
Population growth and development of the earthwormLumbricus rubellusin a polluted field soil: Possible consequences for the godwit (Limosa limosa)
Authors: Klok Chris , van der Hout Annemariet , Bodt Jos 
Published: January 2006

AbstractMany soils are polluted with mixtures of moderate levels of contaminants. In The Netherlands 175,000 sites in rural areas are classified as highly polluted. However, it remains unclear to what extent local ecosystems are endangered. In this paper, we report on the effect of contaminants on earthworms in a meadow system. We tested a polluted and a reference field soil with similar soil characteristics and agricultural use. In the polluted soil copper, mercury, and lead were elevated by more than 200% compared with the reference soil. Bioassays on growth and reproduction in the earthworm species Lumbricus rubellus were executed in both soils, and a population model was used to assess the population-level consequences of changes in growth and reproduction. No significant effects were seen on reproduction and survival in L. rubellus, but development was retarded in the polluted soil. This resulted in a 23% lower growth rate and a change in demography toward younger individuals. Field data on population composition of earthworms were used to support the laboratory results, and the relevance of the results for the godwit (Limosa limosa), which mainly feeds on earthworms during the breeding season, is discussed.
Evaluation of a predictive model for air/surface adsorption equilibrium constants and enthalpies
Authors: Arp Hans Peter H. , Goss Kai-Uwe , Schwarzenbach René P. 
Published: January 2006

Abstract
A model used to predict equilibrium adsorption to surfaces using a poly-parameter linear free-energy relationship as well as an empirical model used to predict enthalpies of adsorption of volatile compounds were evaluated with new experimental data to cover semivolatile compounds and a larger variability of compound classes. Equilibrium adsorption constants on a quartz surface ranging over seven orders of magnitude were measured for 142 compounds, and enthalpies of adsorption on a quartz surface from −33.7 to −99.8 kJ/mol were measured for 76 compounds. Agreement between experimental and predicted data was within a factor of two (82.1%) or three (100.0%) for the equilibrium adsorption constants and within 20% for the enthalpy of adsorption values. Thus, the scatter in the validation data sets reported here were practically the same as that for the calibration data sets used to derive the models. The few outliers that we identified in the prediction of equilibrium adsorption constants likely are caused by either shortcomings of the reported sorbate parameters or the occurrence of chemical speciation in the water layer on the surface of the quartz.
Acid exposure is an immune disruptor in adult Rana pipiens
Authors: Vatnick Itzick , Andrews Jaime , Colombo Matthew , Madhoun Hareth , Rameswaran Muthuramanan , Brodkin Marc A. 
Published: January 2006

Abstract
Acidic environments are physiological stressors for amphibians. The objective of the present study was to document the effect of an acidic environment on innate immune system function under controlled experimental conditions in Rana pipiens. We developed an in vivo assay, by injecting a suspension of 1-μm fluorescent beads in fluid thioglycollate, to induce peritonitis. The number of peritoneal exudate leukocytes and their phagocytic activity did not increase with thioglycollate injection when frogs were exposed to pH 5.5 compared to when frogs were exposed to pH 7.0. An environment of pH 5.5 disrupted the inflammatory response of frogs compared to an environment of pH 7.0; at pH 5.5, more nonphagocytic leukocytes and fewer highly phagocytic leukocytes were found compared to those in frogs exposed to pH 7.0. Frogs stimulated by thioglycollate injection and exposed to pH 5.5 had a 50% increase in cells that did not exhibit phagocytosis and a 4- to 10-fold reduction in the number of highly phagocytic cells. This is evidence that acid exposure functions as an immune disruptor in adult R. pipiens under laboratory conditions.
Fate of Diuron and Linuron in a Field Lysimeter Experiment
Authors: Guzzella L. , Capri E. , Di Corcia A. , Barra Caracciolo A. , Giuliano G. 
Published: January 2006

ABSTRACTThe environmental fate of herbicides can be studied at different levels: in the lab with disturbed or undisturbed soil columns or in the field with suction cup lysimeters or soil enclosure lysimeters. A field lysimeter experiment with 10 soil enclosures was performed to evaluate the mass balance in different environmental compartments of the phenylurea herbicides diuron [3‐(3,4‐diclorophenyl)‐1,1‐dimethyl‐urea] and linuron [3‐(3,4‐dichlorophenyl)‐1‐methoxy‐1‐methylurea]. After application on the agricultural soil, the herbicides were searched for in soil, pore water, and air samples. Soil and water samples were collected at different depths of the soil profile and analyzed to determine residual concentrations of both the parent compounds and of their main transformation products, to verify their persistence and their leaching capacity. Air volatilization was calculated using the theoretical profile shape method. The herbicides were detected only in the surface layer (0–10 cm) of soil. In this layer, diuron was reduced to 50% of its initial concentration at the end of the experiment, while linuron was still 70% present after 245 d. The main metabolites detected were DCPMU [3‐(3,4‐dichlorophenyl)‐1‐methylurea] and DCA (3,4‐dichloroaniline). In soil pore water, diuron and linuron were detected at depths of 20 and 40 cm, although in very low concentrations. Therefore the leaching of these herbicides was quite low in this experiment. Moreover, volatilization losses were inconsequential. The calculated total mass balance showed a high persistence of linuron and diuron in the soil, a low mobility in soil pore water (less than 0.5% in leachate water), and a negligible volatilization effect. The application of the Pesticide Leaching Model (PELMO) showed similar low mobility of the chemicals in soil and water, but overestimated their volatilization and their degradation to the metabolite DCPMU. In conclusion, the use of soil enclosure lysimeters proved to be a good experimental design for studying mobility and transport processes of herbicides in field conditions.
Ammonia Emissions from Swine Waste Lagoons in the Utah Great Basin
Authors: Harper Lowry A. , Weaver Kim H. , Dotson Richard A. 
Published: January 2006

ABSTRACTIn animal production systems (poultry, beef, and swine), current production, storage, and disposal techniques present a challenge to manage wastes to minimize the emissions of trace gases within relatively small geographical areas. Physical and chemical parameters were measured on primary and secondary lagoons on three different swine farming systems, three replicates each, in the Central Great Basin of the United States to determine ammonia (NH3) emissions. Nutrient concentrations, lagoon water temperature, and micrometeorological data from these measurements were used with a published process model to calculate emissions. Annual cycling of emissions was determined in relation to climatic factors and wind speed was found the predominating factor when the lagoon temperatures were above about 3°C. Total NH3 emissions increased in the order of smallest to largest: nursery, sow, and finisher farms. However, emissions on an animal basis increased from nursery animals being lowest to sow animals being highest. When emissions were compared to the amount of nitrogen (N) fed to the animals, NH3 emissions from sows were lowest with emissions from finisher animals highest. Ammonia emissions were compared to similar farm production systems in the humid East of the United States and found to be similar for finisher animals but had much lower emissions than comparable humid East sow production. Published estimates of NH3 emissions from lagoons ranged from 36 to 70% of feed input (no error range) compared to our emissions determined from a process model of 9.8% with an estimated range of ±4%.
Phosphorus Fractions in Manure from Growing Pigs Receiving Diets Containing Micronized Peas and Supplemental Enzymes
Authors: Ige D. V. , Akinremi O. O. , Nyachoti C. M. , Guenter W. 
Published: January 2006

ABSTRACTDifferent livestock feeds manipulations have been reported to reduce the total P concentration in manure. Information on the influence of these dietary manipulation strategies on the forms of P in manure is, however, limited. This study was, therefore, conducted to investigate the effect of diet manipulation through feed micronization and enzyme supplementation on the forms of P in swine manure. Eight growing pigs were fed four diets: barley–raw pea (BRP), barley–micronized pea (BMP), barley–raw pea with enzyme (BRPE), and barley–micronized pea with enzyme (BMPE) in a 4 × 4 Latin square design. Because we are interested in the effect of enzyme cocktail and pea micronization on manure P, we did not reduce the non‐phytate P with enzyme addition in this study. The fecal material and urine were collected and analyzed for total P. Fecal material was fractionated to determine the total P in H2O‐, NaHCO3–, NaOH‐, and HCl‐extractable fractions. The total P in the residual fractions was also determined. About 98% of the total P excreted by the pigs was found in the fecal material. Inclusion of micronized pea in pig diet did not have any significant effect (p > 0.1) on either the total P or the different P fractions in the manure. The labile P (the sum of H2O‐P and NaHCO3–P) was significantly reduced (p < 0.05) by the addition of enzyme to swine diets. Pigs fed the BRPE and BMPE had 14 and 18% lower labile P, respectively, compared with pigs fed the BRP. Enzyme addition to pig diets reduced not only the total P in manure, but also the labile P fraction, which is of great environmental concern. Thus, the potential of P loss to runoff and the subsequent eutrophication can be reduced by enzyme addition to pig diets.
A Model for Linking the Effects of Parathion in Soil to its Degradation and Bioavailability Kinetics
Authors: Saffih‐Hdadi K. , Bruckler L. , Lafolie F. , Barriuso E. 
Published: January 2006

ABSTRACTParathion is an insecticide of a group of highly toxic organophosphorus compounds. To investigate the dissipation and toxicological impact of parathion [O,O‐diethyl O‐(4‐nitrophenyl) phosphorothioate] and its highly toxic metabolite, paraoxon, soil laboratory experiments were conducted in columns during a 19‐d experiment under variably saturated conditions. Water and pesticide transport, sorption, and biodegradation of parathion were measured in three soil pools (soluble phase, weakly and strongly sorbed phases) using C‐labeled pesticide. The effects of parathion and its metabolite on the mobility of soil nematodes were observed and then modeled with an effective variable, which combined pesticide concentration and time of application. Results showed that parathion was highly sorbed and slowly degraded to a mixture of metabolites. The parent compound and its metabolites remained located in the top 0.06‐m soil layer. A kinetic model describing the sorption, biodegradation, and allocation into different soil pools of parathion and its metabolites was coupled with heat and water transport equations to predict the fate of parathion in soil. Simulated results were in agreement with experimental data, showing that the products remained in the upper soil layers even in the case of long‐term (11‐mo) simulation. The strongly sorbed fraction may be regarded as a pesticide reservoir that regularly provides pesticide to the weakly sorbed phase, and then, liquid phase, respectively. From both modeling and observations, no major toxicological damage of parathion and paraoxon to soil nematodes was found, although some effects on nematodes were possible, but at the soil surface only (0.01‐ and 0.02‐m depth).
Nitrogen and Phosphorus Leaching from Growing Season versus Year‐Round Application of Wastewater on Seasonally Frozen Lands
Authors: Zvomuya Francis , Rosen Carl J. , Gupta Satish C. 
Published: January 2006

ABSTRACTLand application of wastewater has become an important disposal option for food‐processing plants operating year‐round. However, there are concerns about nutrient leaching from winter wastewater application on frozen soils. In this study, P and N leaching were compared between nongrowing season application of tertiary‐treated wastewater plus growing season application of partially treated wastewater (NGS) vs. growing season application of partially treated wastewater (GS) containing high levels of soil P. As required by the Minnesota Pollution Control Agency (MPCA), the wastewater applied to the NGS fields during October through March was treated such that it contained ≤6 mg L−1 total phosphorus (TP), ≤10 mg L−1 NO3–N, and ≤20 mg L−1 total Kjeldahl nitrogen (TKN). The only regulation for wastewater application during the growing season (April through September) was that cumulatively it did not exceed the agronomic N requirements of the crop in any sprayfield. Application of tertiary‐treated wastewater during the nongrowing season plus partially treated wastewater during the growing season did not significantly increase NO3−N leaching compared with growing season application of nonregulated wastewater. However, median TP concentration in leachate was significantly higher from the NGS (3.56 mg L−1) than from the GS sprayfields (0.52 mg L−1) or nonirrigated sites (0.52 mg L−1). Median TP leaching loss was also significantly higher from the NGS sprayfields (57 kg ha−1) than from the GS (7.4 kg ha−1) or control sites (6.9 kg ha−1). This was mainly due to higher hydraulic loading from winter wastewater application and limited or no crop P uptake during winter. Results from this study indicate that winter application of even low P potato‐processing wastewater to high P soils can accelerate P leaching. We conclude that the regulation of winter wastewater application on frozen soils should be based on wastewater P concentration and permissible loading. We also recommend that winter irrigation should take soil P saturation into consideration.
Diuron in Surface Runoff and Tile Drainage from Two Grass‐Seed Fields
Authors: Rupp David E. , Peachey R. Edward , Warren Kristina L. , Selker John S. 
Published: January 2006

ABSTRACTThe typical method of cool‐season grass‐seed production in Mediterranean climates briefly exposes surface waters to potentially high concentrations of the herbicide diuron [3‐(3,4‐dichlorophenyl)‐1,1‐dimethyl urea] during the initial season of growth. To better understand the process, and the degree, of diuron transport from agricultural fields, two grass‐seed fields in the Willamette Valley of Oregon were monitored for diuron loss in surface runoff and tile drainage during the first wet season after planting. Initial diuron concentrations in surface runoff were high (>1000 μg L−1 in one field and >100 μg L−1 in the other), though they decreased by two orders of magnitude by the end of the season. Concentrations in the tile drains were as much as 1000 times lower than in the surface runoff during the first few weeks of runoff events, and they remained lower than surface water concentrations throughout the season. Total losses in surface runoff were between 1.3 and 3% of the amount applied—much higher than losses via the tile drains. It is also shown by means of a simple first‐order decay model that, when little information is available, it may be best to describe diuron depletion in runoff water as a function of cumulative rainfall during the wet season.
Adaptation of the Ion Exchange Method for the Determination of the Free Ionic Fraction of Cadmium in Solution
Authors: Schneider André 
Published: January 2006

ABSTRACTThe understanding of the availability of a metal in soil necessitates a minimum knowledge about its speciation in the soil solution. Here, we evaluated an alternative to the use of ion exchangers for estimating the free ionic fraction of cadmium (FCd) in solution. It is based on the exchange selectivity coefficient (VK) rather than the distribution coefficient (DK) to estimate FCd Because VK for the Cd–Ca exchange for the used Amberlite resin was independent of the solution Ca concentration (0.5–7.5 mM) and pH (range: 4.5–6), the experiment on a solution mimicking the analyzed solution to estimate VK was not necessary. The influence of variable Ca and Mg concentrations in solution on FCd was assessed in synthetic solutions containing either citrate or malate. The best way to estimate FCd seemed to treat the exchange data as if Ca was solely present. However, neither the proposed approach nor those applying DK prevent the overestimation of FCd when Ca is partly complexed in the analyzed solution. A method intending to estimate two replicates of FCd for a given, unique solution was also studied on solutions issued from sorption–desorption experiments performed on a humic podzol. It consists of two successive supplies of a known resin mass to a unique sample. Both estimates were close and not significantly different.
Upland Disturbance Affects Headwater Stream Nutrients and Suspended Sediments during Baseflow and Stormflow
Authors: Houser Jeffrey N. , Mulholland Patrick J. , Maloney Kelly O. 
Published: January 2006

ABSTRACTBecause catchment characteristics determine sediment and nutrient inputs to streams, upland disturbance can affect stream chemistry. Catchments at the Fort Benning Military Installation (near Columbus, Georgia) experience a range of upland disturbance intensities due to spatial variability in the intensity of military training. We used this disturbance gradient to investigate the effects of upland soil and vegetation disturbance on stream chemistry. During baseflow, mean total suspended sediment (TSS) concentration and mean inorganic suspended sediment (ISS) concentration increased with catchment disturbance intensity (TSS: R2 = 0.7, p = 0.005, range = 4.0–10.1 mg L−1; ISS: R2 = 0.71, p = 0.004, range = 2.04–7.3 mg L−1); dissolved organic carbon (DOC) concentration (R2 = 0.79, p = 0.001, range = 1.5–4.1 mg L−1) and soluble reactive phosphorus (SRP) concentration (R2 = 0.75, p = 0.008, range = 1.9–6.2 μg L−1) decreased with increasing disturbance intensity; and ammonia (NH4+), nitrate (NO3−), and dissolved inorganic nitrogen (DIN) concentrations were unrelated to disturbance intensity. The increase in TSS and ISS during storms was positively correlated with disturbance (R2 = 0.78 and 0.78, p = 0.01 and 0.01, respectively); mean maximum change in SRP during storms increased with disturbance (r = 0.7, p = 0.04); and mean maximum change in NO3− during storms was marginally correlated with disturbance (r = 0.58, p = 0.06). Soil characteristics were significant predictors of baseflow DOC, SRP, and Ca2+, but were not correlated with suspended sediment fractions, any nitrogen species, or pH. Despite the largely intact riparian zones of these headwater streams, upland soil and vegetation disturbances had clear effects on stream chemistry during baseflow and stormflow conditions.
Greenhouse Gas Emissions from Conventional, Agri‐Environmental Scheme, and Organic Irish Suckler‐Beef Units
Authors: Casey J. W. , Holden N. M. 
Published: January 2006

ABSTRACTThe problems of overproduction within the European Union countries and the environmental impact of agriculture have lead to the introduction of schemes that aim to reduce both. Beef (Bos taurus) production forms a large component of the Irish agricultural industry and accounts for more than one quarter of agricultural economic output. Recently, the European CAP (Common Agricultural Policy) has been re‐evaluated to include supplementary measures that encompass the environmental role of agriculture rather than just the production role. A life cycle assessment (LCA) method was adopted to estimate emissions per kilogram of CO2 equivalent per kilogram of live weight (LW) leaving the farm gate per annum (kg CO2 kg−1 LW yr−1) and per hectare (kg CO2 ha−1 yr−1). Fifteen units engaged in suckler‐beef production (five conventional, five in an Irish agri‐environmental scheme, and five organic units) were evaluated for emissions per unit product and area. The average emissions from the conventional units were 13.0 kg CO2 kg−1 LW yr−1, from the agri‐environmental scheme units 12.2 kg CO2 kg−1 LW yr−1, and from the organic units 11.1 kg CO2 kg LW yr−1 The average emissions per unit area from the conventional units was 5346 kg CO2 ha−1 yr−1, from the agri‐environmental scheme units 4372 kg CO2 ha−1 yr−1, and from the organic units 2302 kg CO2 ha−1 yr−1 Results indicated that moving toward extensive production could reduce emissions per unit product and area but live weight production per hectare would be reduced.