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Salinomycin sodium (BIO COX) is a polyether ionophore, commonly used in the poultry industries for the prevention of coccidial infections and promotion of growth. Salinomycin sodium (SAL-Na) is very toxic, and may be fatal, if swallowed, inhaled or absorbed through the skin than many other antibiotics, thus evaluating its fate in the soil environment is of importance. Mobility of SAL-Na was measured in sandy soil. Soil column leaching experiments indicated that the strongly sorbed SAL-Na was not detected in the leachate of sandy soils, indicating that the amount added to each column was not leached off the soil fractions. When compared to the sterile soil, non sterile soil has more movement of SAL-Na. Leachate collected from the soil column (75% hydraulic conductivity) passed with phosphate buffer showed higher concentration (0.48 mg/L) of SAL-Na and the movement was also observed higher in non sterile soil. About 35% of SAL-Na was found in leachate of sandy soil. [ABSTRACT FROM AUTHOR]

Groundwater depletion poses a significant threat in arid and semi-arid areas where rivers are usually ephemeral and groundwater is the major source of water. The present study investigated whether an effective water resources management strategy, capable of minimizing evaporative water losses and groundwater depletion while providing water for expanded agricultural activities, can be achieved through aquifer storage and recovery (ASR) implemented in conjunction with water storage in an ephemeral river. A regional development modeling framework, including both ASR and a dam design developed through system dynamics modeling, was validated using a case study for the Sirik region of Iran. The system dynamics model of groundwater flow and the comprehensive system dynamics model developed in this study showed that ASR was a beneficial strategy for the region's farmers and the groundwater system, since the rate of groundwater depletion declined significantly (from 14.5 meters per 40 years to three meters over the same period). Furthermore, evaporation from the reservoir decreased by 50 million cubic meters over the simulation period. It was concluded that the proposed system dynamics model is an effective tool in helping to conserve water resources and reduce depletion in arid regions and semi-arid areas. [ABSTRACT FROM AUTHOR]

The sorption behavior of atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine), a commonly used herbicide for corn, on intact soil columns was studied by incorporating a new two-stage sorption mechanism into PESTFADE, a pesticide fate and transport model. This mechanism takes into account intraparticle diffusion of pesticide into the soil matrix (also sometimes known as bound residues), the sorption capacity of soil, and a variable pesticide distribution coefficient [K.sub.d]. The modified model's performance was verified by comparing simulated values with those obtained from an intact column study in the laboratory. The two-stage mechanism was also compared and contrasted with the conventional adsorption approach based on a constant [K.sub.d]. Simulations with the two-stage mechanism indicated a closer agreement with measured values (deviations in the range of 5-65%) than that of the conventional adsorption approach (deviations in the range of 10-700%). Furthermore, it was found that simulated values were particularly sensitive to soil tortuosity [Tau], soil bulk density [Rho], soil moisture content [[Theta].sub.w], labile sorption capacity [[Theta].sub.c], and intraparticle diffusion parameters.

Given the water scarcity becoming endemic to a large portion of the globe, arid region irrigation has resorted to the use of treated, partially treated, or even untreated wastewaters. Such waters contain a number of pollutants, including surfactants. Applied to agricultural lands, these surfactants could affect the fate and transport of other chemicals in the soil, particularly pesticides. A field lysimeter study was undertaken to investigate the effect of nonionic surfactant, Brij35, on the in-soil fate and transport of a commonly used herbicide, metribuzin [4-amino-6-tert-butyl-3-(methylthio)-1,2,4-triazin-5(4H)-one]. Nine PVC lysimeters, 1.0 m long x 0.45 m diameter, were packed with a sandy soil to a bulk density of 1.35 mg m-3. Antibiotic-free cattle manure was applied (10 mg ha-1) at the surface of the lysimeters. Metribuzin was then applied to the soil surface of all lysimeters at a rate of 1.00 kg a.i. ha-1. Each of three aqueous Brij35 solutions, 0, 0.5 and 5 mg L-1 (i.e., "good", "poor" and "very poor" quality irrigation water) were each applied to the lysimeters in triplicate. Analysis for metribuzin residues in samples of both soil and leachate, collected over a 90-day period, showed the surfactant Brij35 to have increased the mobility of metribuzin in soil, indicating that continued use of poor quality water could influence pesticide transport in agricultural soils, and increase the risk of groundwater contamination. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the relationship of urban environmental conditions and the growth patterns of trees. It explores the factors that modulate the survival and growth of trees in urban site through contingency analyses of abiotic data collected locally from various trees including silver maple. Results show that the species demonstrated ecological tolerance and found out the importance of ample irradiation intensity as a factor that contributes to urban tree growth.

The article presents a study which assesses the significance of the low-technology street tree inventory guideline. To evaluate the parameters' significance, a three-step multivariate statistical analysis and was employed on the growth models of several trees such as the Norway maple, hackberry and green ash. Results of the study suggests that quantitative parameters should be preferred for urban tree inventory.

Efforts were made to predict pesticide concentrations at three different depths in the soil profile, using models developed with Multivariate Adaptive Regression Splines (MARS), a regression analysis model. The models were developed with independently collected data from the Eugene E Whelan Experimental Farm (Agriculture and Agri-Food Canada, Woodslee, Ontario, Canada) from 1992 to 1994. Data from 16 plots, subjected to four different tillage treatments and two different water table management practices, were used. The fate of three herbicides, namely atrazine [2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine], metribuzin [4-amino-6-(1, 1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one], and metolachlor 12-chloro-N-(2-ethyl-6-methylphenyl)-N-(-2-methoxyl-1-methylethyl) acetamide], at three different soil depths were studied. The input variables for the models included Julian day, days after application of pesticide, measured herbicide concentrations, and cumulative figures for rainfall depth, air temperature, soil temperature, and potential evapotranspiration. Considering the limited size of the data set, a 10-fold cross-validation was performed to test and validate the model. Model predictions at the 0-10 cm depth were very close to the measured values, with model efficiencies varying from 83% to 99%. The predictions at the 10-15 cm depth generally varied from 33% to 83%, while the ones at the 15-20 cm depth were within 42% to 95%, with a few exceptions where the model predicted a single value, of the average observed concentrations. These results demonstrate that MARS was able to do a commendable job in simulating pesticide fate and transport in soil with limited data. [ABSTRACT FROM AUTHOR]

Determines the electron affinity coefficients for nitrogen oxides in the denitrification process with the use of continuous reactions, as opposed to batch reactions. Effectiveness of the use of continuous reactions as well as batch reactions in determining the affinity coefficients in denitrification; Similarity of the obtained affinity coefficient of nitrogen oxide, using continuous reactions, to that of other studies in the literature found via batch reactions.

The effects of plant–microbe–soil interactions on the biotransformation of polychlorinated biphenyls (PCBs) in a rhizosphere soil were investigated. Containers packed with 350 g of a soil contaminated with Aroclor 1242, 1248, 1254 and 1260, were planted with alfalfa (Medicago sativa L.) and augmented with its symbiotic N2-fixing host rhizobium (Sinorhizobium meliloti, strain A-025). The four treatment setups comprised a factorial combination of the presence/absence of alfalfa with the non-inoculation/inoculation of soil with S. meliloti in a completely randomized design with two replicates. Up to 44 days after planting, when the alfalfa was not fully developed, alfalfa and S. meliloti together were the most effective in PCB transformation/depletion, whereas alfalfa only was the least effective. However, by the last day of the experimental period (Day 270), when alfalfa growth was robust and full, alfalfa alone was the most effective, whereas S. meliloti alone was the least. In rhizobium-inoculated soil, soil hardness increased, soil moisture contents decreased, and both plant growth and yield were lowered, compared to non-inoculated soil. The depletion, loss or change in PCB levels may be attributed to either direct or indirect biotransformation, biotranslocation and adsorption of PCBs due to the presence of alfalfa and/or rhizobial inoculation. Either possibility underscores the possibility of using plant-rhizobacterial associations to phytoremediate soils contaminated with PCBs. [Copyright &y& Elsevier]

Discusses the biofiltration of residual fertilizer nitrate and atrazine by Rhizobium meliloti A-025 bacteria in saturated and unsaturated sterile soil columns. Concentration of nitrate and atrazine residues in soil and drainage waters after each simulation rainfall; Transport and survival of the bacteria.

Food crops irrigated with wastewater can uptake heavy metals, causing serious health ailments in humans. Use of a polyacrylamide superabsorbent polymer hydrogel and the same hydrogel mixed with pyrolyzed plantain peel biochar as soil amendments are proposed to reduce heavy metal uptake by wastewater-irrigated spinach (Spinacia oleracea L.) plants. A sorption test was carried out to establish the ability of these treatments to bind the heavy metals. In a lysimeter field experiment, the amendments were mixed in the top 0.10 m of soil (1% w/w) and spinach plants were grown using synthetic wastewater irrigation. After each irrigation, soil samples were obtained at different depths (0, 0.10, 0.30, and 0.60 m from the surface) for heavy metal analysis. Spinach leaves, root, and stem samples were obtained at the harvest for metal analysis. Sorption test results showed that the hydrogel-biochar amended soil adsorbed 0.80, 0.46, and 0.44 mg g−1 of cadmium, copper, and zinc, respectively, from a 0.5 mM multi-metal solution; the hydrogel treatment adsorbed 0.59, 0.41, and 0.24 mg g−1 of the metals, respectively. These amounts were at least 90% more than those adsorbed by the non-amended soil. In terms of the total metal uptake by spinach leaves, the hydrogel-biochar mix treatment performed better than the hydrogel treatment; it reduced the total uptake by 48%, whereas the hydrogel treatment was only able to reduce it by 15% when compared to the control that exhibited a total metal load of 1028 mg kg−1. Both treatments were able to significantly (p < 0.05) reduce copper uptake in plant stems, and exhibited the potential to reduce chromium, copper, and iron uptake by spinach leaves. • Irrigating spinach with wastewater led to accumulation of heavy metals in topsoil. • Hydrogel treated soil retained higher amounts of Cr, Cu and Fe. • Hydrogel based soil amendments reduced Cu and Cd uptake in spinach plants. • Hydrogel-biochar treatment performed best in reducing metal uptake in spinach leaves. [ABSTRACT FROM AUTHOR]

A point-of-use household water treatment technology, the biosand filter (BSF), has been widely adopted across over 180 countries (CAWST, 2020). However, it has a poor Escherichia coli (E. coli) removal efficiency during the first few weeks of its use. This study investigated the potential of biochar on E. coli removal in a laboratory-modified biosand filtering system. Two biochars, produced from wheat straw and willow wood feedstocks, were used and their effects were compared. Only the coarser fraction of both biochars (1–4 mm) was used in order to minimize its impact on the filtration rate. It was observed that the filter amended with wheat straw biochar exhibited a higher mean E. coli removal rate (84%) than the filter amended with willow wood biochar (79%); however, both biochar-amended filters had lower mean E. coli removal rates than the sand-only control filter (88%), over a 5-week filtration experiment. The E. coli adsorption of biochar and sand were examined at the end of the filtration experiment. Both biochars were shown to have a larger total amount of E. coli adsorption (7.4 log 10) than sand (6.8 log 10). The two biochars showed comparable E. coli adsorption capacities of 5.7 log 10 CFU/g, although their specific surface areas varied greatly (55.24 m2/g for wheat straw biochar and 380.00 m2/g for willow wood biochar). The discrepancy between the results of E. coli removal and E. coli adsorption might indicate the importance of biochar straining; the absence of fine biochar particles (< 1 mm), was potentially responsible for the reduced E. coli removal efficiency. Additionally, biochar was found to increase effluent's pH, electrical conductivity (EC) and phosphate content, with more significant increases noticed during the first 2 weeks. Thus, extra assessment on these drinking water properties would be necessary. Overall, our study suggests that biochar amendment might not be suitable for the BSF. However, further confirmation is needed, and future research on examining the effect of biochar size, on the efficiency of BSF is recommended. • Effect of two biochars in a biosand filter on E. coli removal was investigated • Both biochars lowered filter's E. coli removal efficiency • Wheat straw biochar showed higher E. coli removal than willow wood biochar • Both biochars exhibited higher E. coli adsorption capacity than sand • Biochar treatment increased effluent's pH, EC and phosphate content [ABSTRACT FROM AUTHOR]

The quantity, intensity, and quality of urban stormwater runoff are changing as a consequence of urbanization and climate change. Low impact development (LID) techniques (e.g., bioretention systems) are emerging to manage runoff quantity and quality. Street tree pits were used as bioretention units in Montreal, Canada. The concentration and mass flux of contaminants (Na, Cr, Ni, Cu, Zn, Cd, Pb) and dissolved organic carbon (DOC) were measured in soil solution samples from the tree pits. The soil organic matter (SOM) and the permeability of the area nearby the tree pit (sidewalk and front lawn) were tested. The SOM did not affect contaminant concentrations. However, tree pits with higher SOM reduced the mass flux of contaminants more than tree pits with lower SOM. Sidewalk permeability decreased the concentration and mass flux of contaminants observed (e.g., Na and Cr). The estimated water flux in the open part of the tree pit changed from 6.15 to 1.64 mm week−1 from the less permeable units (absence of lawn + impermeable sidewalk) to the more permeable units (presence of lawn + permeable sidewalk). Urban runoff quality and quantity were locally affected by the tree pits. This indicates that the increase in surface permeability and SOM in street tree pits is advisable. Street tree pits have the potential as bioretention units to locally mitigate some of the impacts of urbanization. City planners could consider the use of street tree pits as bioretention units to help the management of urban runoff. [ABSTRACT FROM AUTHOR]

Water pollution by nitrate removed from agricultural systems through subsurface tile drains is a major environmental concern in Ontario. The control and reduction of the loading of chemicals to water bodies requires knowledge on the contribution of agricultural systems to water pollution under different cropping management practices. In this study, DRAINMOD model was implemented to predict the effects of conventional tillage (CT) and no tillage (NT) treatments on water table depth, tile effluent and NO 3 –N losses through subsurface drainage from a 14 ha agricultural field at the Green Belt Farm of Agriculture and Agri-Food Canada in Ottawa, Ontario. During the study period, flow was significantly higher under NT than CT mainly during the snowmelt and spring periods. Total nitrate loss under NT was higher than CT but the difference was not significant during the 4 years of study period. The climate change scenario of PRECIS was then applied to assess the effect of tillage practices under future climate change. In the future, the changes in climate will result in a significant increase in flow and nitrate under both NT and CT practices. It was also noted that, in future, NO 3 –N losses under no till treatment are expected to be significantly higher than those under conventional tillage practices in future. [ABSTRACT FROM AUTHOR]

The bioavailability of heavy metals in compost is critical for their agronomic value. The effect of inorganic additives (rock phosphate, PR and boron waste, BW) on Copper (Cu) and Zinc (Zn) bioavailability during co-compost of swine manure and rice straw was assessed using sequential extraction procedure (European Community Bureau of Reference). The result showed that both additives, applied at rates of 2.5%–7.5% (w/w) could promote the change of exchangeable Cu and reducible Cu into oxidizable Cu, thereby reducing their bioavailability factor (BF) by 15.5%–47.2%. While additives provided no significant reduction in BF of Zn, the shift from exchangeable Zn into reducible Zn can still reduce the mobility of Zn. Based on redundancy analysis (RDA), organic matter (OM) and electrical conductivity (EC) were identified as the most important controlling factors for redistribution of Cu and Zn fractions during composting. The inorganic additives strengthened the passivation of Cu and Zn bioavailability by stimulating OM degradation. The 7.5% (w/w) rock phosphate showed best passivating effect on the bioavailability of Cu. • A novel approach to utilize boron waste（BW）was adopted. • Rock phosphate and boron waste were suitable passivator of Cu, Zn during composting. • Organic matter and electrical conductivity can explain the redistribution of Cu and Zn. • Inorganic additives strengthened the passivation of Cu by promoting OM degradation. [ABSTRACT FROM AUTHOR]

• Composting decreased the bioavailability of Cu, Zn and the mobility of P. • Degradation of organic matter controlled redistribution of Cu, Zn and P fractions. • A C/N ratio of 22 most effectively reduced the mobility of Cu and P. • Zn fractions was unaffected by chemical parameters during compost. The status of heavy metals and the P fractions in compost affects their environmental risk. The present study investigated the effects of different initial carbon to nitrogen (C/N) ratios (15, 22, 27) on redistribution of Cu, Zn, and P fractions during composting. The results showed that the composting process transformed Cu, Zn and P from mobile fractions to more stable fractions. Compost with an initial C/N of 22 showed the most effective immobilization of Cu, Zn and P because of yielding greatest degree of polymerization. Multivariate statistical analysis identified organic matter as the most critical factor for explaining the redistribution of Cu, Zn, and P fractions in composting. However, the degree of organic matter degradation (organic matter content and Humic acid/Fulvic acid) better explained the change of bioavailability factor for Cu and the mobility of P during composting. This research provided guidance for providing technology to reduce environmental risk in compost. [ABSTRACT FROM AUTHOR]

Nitrate contamination of groundwater is an environmental concern in intensively cultivated desert oases where this polluted groundwater is in turn used as a major irrigation water resource. However, nitrate fluxes from root zone to groundwater are difficult to monitor in this complex system. The objectives of this study were to validate and apply the WHCNS (soil Water Heat Carbon Nitrogen Simulator) model to simulate water drainage and nitrate leaching under different irrigation and nitrogen (N) management practices, and to assess the utilization of groundwater nitrate as an approach to remediate nitrate contaminated groundwater while maintain crop yield. A two-year field experiment was conducted in a corn field irrigated with high nitrate groundwater (20 mg N L −1 ) in Alxa, Inner Mongolia, China. The experiment consisted of two irrigation treatments (I std , standard, 750 mm per season; I csv , conservation, 570 mm per season) factorially combined with two N fertilization treatments (N std , standard, 138 kg ha −1 ; N csv , conservation, 92 kg ha −1 ). The validated results showed that the WHCNS model simulated values of crop dry matter, yield, soil water content and soil N concentration in soil profile all agreed well with the observed values. Compared to the standard water management (I std ), the simulated drainage and nitrate leaching decreased about 65% and 59%, respectively, under the conservation water management (I csv ). Nearly 55% of input N was lost by leaching under the I std N std and I std N csv treatments, compared to only 26% under the I csv N std and I csv N csv treatments. Simulations with more than 240 scenarios combing different levels of irrigation and fertilization indicated that irrigation was the main reason leading to the high risk of nitrate leaching, and the nitrate in irrigation groundwater can be best utilized without corn yield loss when the total irrigation was reduced from the current 750 mm to 491 mm. This reduced irrigation rate facilitated the use of approximately 42 kg N ha −1 yr −1 of nitrate from groundwater, which would gradually improve the groundwater quality. Future field studies on nitrate leaching in this area are suggested to investigate water and N dynamics under irrigation rates near 490 mm per season. [ABSTRACT FROM AUTHOR]

Emerging contaminants (ECs) in aquatic environments have recently attracted the attention of researchers due to their ubiquitous occurrence and the potential risk they may pose to life. While advance analytical methods have improved global reporting in water matrices, additional information is needed to compile data on their occurrence, existing legislation, treatment technologies and associated human health risks. Therefore, the present study provides an overview of the occurrence of selected ECs, including personal care product, antibiotics, NSAIDs, EDCs and psychiatric drugs, the existing regulatory framework and their toxicological effects on human health. The water matrices under review are the treated wastewater, surface water, groundwater and, in a few cases, drinking water. The study also highlights different treatment technologies available, and evaluates their performance based on the removal efficiency for different classes of ECs. For removal of almost all ECs considered, ozonation integrated with gamma radiation was reported highly efficient. Risk analysis was also performed for selected ECs including diclofenac, ibuprofen, naproxen, carbamazepine, estrone, 17 β-estradiol, bisphenol A, sulfamethoxazole, erythromycin and triclosan. The human health risk analysis indicated the highest number of locations with potential risk due to the EDCs, with South America, Europe and Asia having multiple risks due to estrone and Bisphenol A. The results of this study will give a better insight into the current situation of ECs in the global water matrices, the performance assessment of treatment technologies and the risk analysis will describe the need for more robust regulatory structures around the world to prevent the occurrence of such contaminants in the aquatic environment., Competing Interests: Declaration of Competing Interest The authors confirm that they have no known competing financial interests or personal relationships that could have biased the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The feasibility of using two types of biochars to reduce steroid hormone pollution from poultry and swine manure application on agricultural land was evaluated. The sorption affinity and desorption resistance of softwood and hardwood biochars were also determined for two estrogen hormones, 17β-estradiol (E2) and its primary metabolite estrone (E1). The softwood and hardwood biochars demonstrated high retention capacity for both estrogens. The effective distribution coefficient (K d eff ) of soil-softwood-derived biochar (SBS 450 ) was significantly higher than soil-hardwood-derived biochar (SBH 750 ), indicating the stronger sorption affinity of SBS 450 for estrogens. To validate the laboratory results, a field lysimeter experiment was conducted to study the fate and transport of E2 and E1 in soil and leachate in the presence of 1% softwood-biochar (BS 450 ) in topsoil and to compare it with soil without any amendments. The spatio-temporal distribution of both estrogens was monitored at four depths over a 46-day period. The lysimeters, in which the surface layer of soil was amended with biochar, retained significantly higher concentrations of both estrogen hormones. Although they leached through the soil and were detected in leachates, collected at 1.0m depth, the concentrations were significantly lower in the leachate collected from biochar-amended lysimeters. The result confirmed the efficacy of biochar amendment as a remediation technique to alleviate the manure-borne hormonal pollution of groundwater., (Copyright © 2018. Published by Elsevier B.V.)