Permeable pavements mitigate the impacts of urbanization on surface waters through pollutant load reduction, both by sequestration of pollutants and stormwater volume reduction through exfiltration. This study examined the non-winter water quality performance of two side-by-side permeable pavements in the Ohio snowbelt. The permeable interlocking concrete pavements were designed to drain impervious catchments 2.2 (large) and 7.2 (small) times larger than their surface area, were located over clay soils, and incorporated the internal water storage design feature. Nutrient reduction was similar to past studies—organic nitrogen and particulate phosphorus were removed through filtration and settling, while dissolved constituents received little treatment. Because of 16 and 32 % volume reductions in the small and large installations, respectively, nutrient loads were often significantly reduced but generally by less than 50 %. Aluminum, calcium, iron, magnesium, lead, chloride, and total suspended solids (TSS) concentrations and loads often increased after passing through the permeable pavements; effluent TSS loads were three- to five-fold higher than influent TSS loads. This was apparently due to seasonal release of clay- and silt-sized particles from the soils underlying the permeable pavement and inversely related to elapsed time since winter. The application of de-icing salt is thought to have caused deflocculation of the underlying soils, allowing particulates to exit with stormwater as it discharged from the underdrain of the permeable pavements. By autumn, both permeable pavements discharged metals and TSS concentrations similar to others in the literature, suggesting the de-icing effects lasted 3–6 months post-winter. Sodium may substantially affect the performance of permeable pavements following winter de-icing salt application, particularly when 2:1 clay minerals, such as vermiculites and smectites, predominate.

This work reported a comparative study on the electrochemical incineration of nitrilotriacetic acid (NTA) in the presence of different supporting electrolytes (Na₂SO₄ and NaCl). Galvanostatic electrolyses were conducted in an undivided electrochemical cell containing boron-doped diamond (BDD) anode and platinum cathode. Initial solution pH, flow rate, applied current density, and supporting electrolyte concentration were selected as variables, besides the mineralization efficiency of NTA that was selected as response. Central composite rotatable design and response surface methodology were employed here to examine the statistical significance of the selected variables, as well as to determine the optimal conditions of the degradation process. Under the same operating conditions, two regression models were thus constructed to illustrate the differing impact of supporting electrolytes in BDD anode cells. The kinetics for NTA degradation followed different reaction orders for the two scenarios (in the absence and presence of NaCl), indicating the complex interaction between hydroxyl radicals and active chlorine. Despite this, the experimental results demonstrated that effective mineralization of NTA might also be achieved in the presence of chlorides (of lower concentrations). Besides, in the case of chlorides, the average mass transfer coefficient of the system was found to be strongly dependent on the initial solution pH. Lastly, a plausible reaction sequence concerning the electrolytic oxidation of NTA in chloride media was also proposed.

Phosphorus (P) loss from diffuse sources remains as the main cause of freshwater eutrophication in agricultural regions. The amount of land used for different agricultural practices may be a strong explanatory factor for the P loading to runoff waters. A prerequisite is that the effect of changes in land use on P levels in surface waters needs to be ascertained and quantified. In this study, a comprehensive approach has been developed to explore the environmental consequences of P levels in receiving water with corresponding land use change in a heavily agriculturally influenced watershed. A coupled simulation using Dyna-CLUE model with grey relational analysis (GRA) and grey model GM (1,1) model was employed to stimulate spatial distribution and area demand. Besides, a comprehensive land use index with degree of P saturation (DPS%) as weight coefficient was developed to examine the statistical and spatial relationships of land use and P levels in receiving waters on regional watershed. Moreover, in order to evaluate the practical impact of land use change on water quality, a planned emigration and watershed ecological reconstruction planning were designed into the scenarios. The potential of changes in land use as an abatement action to curb eutrophication was evaluated by modelling the effect of issued emigration and ecological restoration programs in the local watershed of the Yuqiao water reservoir in northeastern China. Kappa indexes above 0.85 for the validation period verify that the coupled land use change model is able to simulate the effect of the abatement actions on land use. Scenario predictions reveals that local emigration and a comprehensive ecological restoration project as abatement actions could significantly decrease contents of P in receiving surface waters: Relative to year 2012, total P and orthophosphate could be reduced by 36 and 45 %, respectively, by the end of year 2018. This modelling approach can, with moderate modifications, also be adapted to other watersheds. The model developed in this study can thus be used by environmental managers as a tool to identify risk for P loss from diffuse sources within a watershed and assist policy makers to assess the effect on P losses by implementing abatement actions that changes land use.

The global sugarcane production is about 1.91 billion tons annually and is concentrated in tropical regions, particularly in developing nations in Latin America and Asia. According to the UN Food and Agricultural Organization (FAO), there are over 100 countries producing sugarcane today. The increase in sugarcane production implies a proportional increase in sugar industry wastes. As a consequence of such increasing trend, sugar industries are facing severe environmental problems due to the lack of sustainable solutions for their waste management. Therefore, immediate attention is required to find a proper way of management to deal with sugar industry wastes and effluent in order to minimize environmental pollution and associated health risks. In this paper, different sources of solid and liquid wastes from sugarcane agriculture and associated sugar agro-industries are reviewed and valorization approaches of these different wastes are discussed. Some of the important resource recovery options from sugar industry wastes, which have been discussed in this review, include ethanol production, recovery of chemicals, use of bagasse and bagasse fly ash as adsorbents in water treatment and building materials. Technologies associated with the treatment of wastewater from sugar industries and efficient ways of utilization of this treated water in agriculture with special attention to measurement of crop water use efficiency are reviewed in view of our own research activities carried out in the past.

The aim of the study was to estimate the impact of oxygen depletion on macroinvertebrate community structure in benthic space. Macroinvertebrate assemblages and potential of dissolved oxygen (DO) consumption were investigated simultaneously in the plain rivers of the Ziya River Basin. The degree of DO depletion was represented by sediment oxygen demand (SOD) and DO, chemical oxygen demand (CODCᵣ), and ammonia nitrogen (NH₄ ⁺-N) in the overlying water. The results showed an all-around hypoxia environment formed, and the values of DO, SOD, CODCᵣ, and NH₄ ⁺-N were separately 0.11–4.03 mg L⁻¹, 0.41–2.60 g m⁻² day⁻¹, 27.50–410.00 mg L⁻¹, and 1.79–101.41 mg L⁻¹. There was an abnormal macroinvertebrate assemblage, and only 3 classes, Insecta, Gastropoda, and Oligochaeta, were found, which included 9 orders, 30 families, and 54 genera. The biodiversity was at a low level, and Shannon-Wiener index was 0.00–1.72. SOD, and NH₄ ⁺-N had major impact on the macroinvertebrate community, and the former had negative effect on most taxa, for instance, Nais, Branchiura, Paraleptophlebia, etc., which were sensitive or had a moderate-high tolerance to pollution. NH₄ ⁺-N had both positive and negative impacts on benthic animals, for instance, Dicrotendipes, Gomphus, Cricotopus, etc., for the former, and Procladius, Limnodrilus, Hippeutis, etc., for the latter. They all had a moderate-high tolerance to pollution. It is significant to improve DO condition and macroinvertebrate diversity in river harnessing and management.

The present study examines the efficiency of soil amendments regarding the retention of chromate ions, from water and cultivated soil with wheat (Triticum durum). The minerals and iron oxides that have been used were zeolite, bentonite, goethite, and zeolite modified with goethite I and II. Each adsorbent was added to different Cr solutions, either Cr(NO₃)₃·9H₂O or CrO₃ in a proportion of 1/100 g adsorbent mL⁻¹ solution. Moreover, greenhouse experiments were also conducted using the above materials as soil amendments. Two doses of chromate ions, i.e., 50 mg Cr(III) L⁻¹ in the form of Cr(NO₃)₃·9H₂O and 1 mg Cr(VI) L⁻¹ in the form of CrO₃, were added to plant pots cultivated with wheat. According to the results, the uptake of chromate ions from aqueous solutions onto different adsorbents has shown that modified zeolites (Z-G I and II) adsorb the highest amount of chromate ions, compared to all the other adsorbents. The statistical analysis of the greenhouse experimental data has shown that the increase of the dry weight in soils with amendments follows the order: Z-G II > G > Z-G I > B > Z for pots where Cr(NO₃)₃·9H₂O solutions were added and Z-G II > G > Z > Z-G I > B for pots where CrO₃ solutions were added, respectively. Moreover, all the used soil amendments reduced the total Cr concentration in plants, especially Z-G II. Consequently, such modified zeolites can be used for the remediation of polluted soils with chromium and the production of high-quality food products.

Tunis Gulf (northern Tunisia, Mediterranean Sea) is of great economic importance due to its abundant fish resources. Rising urbanization and industrial development in the surrounding area have resulted in an increase in untreated effluents and domestic waste discharged into the gulf via its tributary streams. Metal (Cd, Pb, Hg, Cu, Zn, Fe, and Mn) and major element (Mg, Ca, Na, and K) concentrations were measured in the grain fine fraction <63 μm by atomic absorption spectrophotometry. Results showed varying spatial distribution patterns for metals, indicating complex origins and controlling factors such as anthropogenic activities. Sediment metal concentrations are ranked as follows: Fe > Mg > Zn > Mn > Pb > Cu > Cd > Hg. Metals tend to be concentrated in proximity to source points, suggesting that the mineral enrichment elements come from sewage of coastal towns and pollution from industrial dumps and located along local rivers, lagoons, and on the gulf shore itself. This study showed that trace metal and major element concentrations in surface sediments along the Tunis Gulf shores were lower than those found in other coastal areas of the Mediterranean Sea.

Four heavy metals (Cd, Cu, Pb and Zn), two metalloids (As and Sb) and two rare metals (In and Tl) were selected as target elements to ascertain their concentrations and accumulation in the soil-plant system and their effects on the structure of the soil microbial community in a typical area of rare metal smelting in south China. Twenty-seven soil samples 100, 500, 1000, 1500 and 3000 m from the smelter and 42 vegetable samples were collected to determine the concentrations of the target elements. Changes in soil micro-organisms were investigated using the Biolog test and 454 pyrosequencing. The concentrations of the eight target elements (especially As and Cd) were especially high in the topsoil 100 m from the smelter and decreased markedly with increasing distance from the smelter and with increasing soil depth. Cadmium bio-concentration factors in the vegetables were the highest followed by Tl, Cu, Zn, In, Sb, Pb, and then As. The concentrations of As, Cd and Pb in vegetables were 86.7, 100 and 80.0 %, respectively, over the permissible limits and possible contamination by Tl may also be of concern. Changes in soil microbial counts and average well colour development were also significantly different at different sampling distances from the smelter. The degree of tolerance to heavy metals appears to be fungi > bacteria > actinomycetes. The 454 pyrosequencing indicates that long-term metal contamination from the smelting activities has resulted in shifts in the composition of the soil bacterial community.

This study is concerned with the removal performance of the antibiotic ciprofloxacin (CIP) from synthetic solutions by electrocoagulation (EC), as well as the toxic effects of treated CIP solutions. A response surface analysis (RSA) was applied to search optimal operational parameter values of the pH of solution, electrical current density (ECD), and electrolysis time (ET). The EC efficiency was evaluated by determining the total organic carbon (TOC) and CIP concentration performed by high-performance liquid chromatography. Although the best EC efficiency was attained at pH = 8, ECD = 22.2 A m⁻², and ET = 75 min, toxicity and antibacterial tests were performed using Artemia salina cysts and Staphylococcus aureus and Escherichia coli microorganisms in a wide ET range and other pH and ECD values. Increasing optimal pH value (9), along with reducing optimal ECD value (18 A m⁻²) and regarding low ET values, similar results for the removal of CIP (98%) and TOC (87%) were also attained. Toxicity variation was observed during EC process in synthetic solutions with the lowest antibacterial effects due to CIP and recalcitrant compound residues after 40 min of ET. These results clearly showed that the EC process presents a promising alternative method for the treatment of wastewaters containing high CIP concentrations.

This manuscript reports on a study of new biocatalysts for the biodegradation of pyrethroid pesticides, such as esfenvalerate. Experiments of esfenvalerate biodegradation by bacteria isolated from Brazilian savannah (Curtobacterium sp. CBMAI 1834, Bacillus sp. 2B, Lysinibacillus sp. CBMAI 1837, and Bacillus sp. 4T), sea (Kocuria sp. CBMAI 135, Kocuria sp. CBMAI 136, Kocuria marina CBMAI 141, and Kocuria sp. CBMAI 145), and a tropical peat usually known as “turfa” soil (Bacillus sp. P5CBNB, Kosakonia sp. CBMAI 1836, Bacillus sp. CBMAI 1833, and Kosakonia sp. CBMAI 1835) were performed. A biodegradation pathway was proposed for a better understanding of the environmental fate of the above mentioned insecticide. Esfenvalerate (S,S-fenvalerate) and its metabolites [3-phenoxybenzaldehyde (PBAld), 3-phenoxybenzoic acid (PBAc), 3-phenoxybenzyl alcohol, and 2-(4-chlorophenyl)-3-methylbutyric acid) (CLAc)] were quantitatively analyzed in triplicate experiments by a validated method. Initially, 100 mg L⁻¹ esfenvalerate (Sumidan 150SC) was added for each experiment. The residual esfenvalerate (104.7–41.6 mg L⁻¹) and formation of PBAc (0.1–8.1 mg L⁻¹), ClAc (1.5–11.0 mg L⁻¹), PBAlc (0.9 mg L⁻¹), and PBAld (completely biotransformed) were quantified. The 12 bacterial strains accelerated (with different efficiencies) the esfenvalerate degradation and increased the metabolites concentrations. A new and more complete biodegradation pathway based on HPLC-time of flight (ToF) and gas chromatography-mass spectrometry (GC-MS) analyses (in which thermal instability products were detected) was proposed. The detected metabolites are smaller and more polar compounds that may be carried by water and contaminate the environment.