Performance of a laboratory-scale integrated baffled reactor for the treatment of raw palm oil mill effluent (POME) was investigated. Initially, the reactor was fed with diluted POME (COD = 1,830 mg/L and OLR = 0.46 g COD/L day) which was then increased gradually to actual concentration (COD = 45,500 mg/L and OLR = 11.38 g COD/L day). Reactor operation was studied in two different hydraulic retention times (HRTs) (4 and 6 days) using POME with no effluent-recycled feed and after alkalinity supplementation. Chemical oxygen demand (COD) removal of 79 and 83 % at an HRT of 4 and 6 days were attained at the highest organic loading rate (OLR = 11.38 g COD/L day). The presence of Arcella-like and Metopus-like species and pH profile in the bioreactor’s compartments imply that anaerobic system is active in the reactor throughout the study. Use of methanogen-enriched inocula, smooth OLR augmentation, and appropriate separation of acidogens and methanogens in the reactor were the reasons for satisfactory performances of the system.

A soil core collected in a tidal freshwater marsh in the Waccamaw National Wildlife Refuge (Georgetown, SC) exuded a particularly strong odor of cow manure upon extrusion. In order to test for manure and determine its provenance, we carried out microbial source tracking using DNA markers for Bacteroides, a noncoliform, anaerobic bacterial group that represents a large proportion spectrum of the fecal population. Three core sections from 0–3 cm, 9–12 cm, and 30–33 cm were analyzed for the presence of Bacteroides. The ages of core sediments were estimated using²¹⁰Pb and¹³⁷Cs dating. All three core sections tested positive for Bacteroides DNA markers related to cow or deer feces. Because cow manure is stockpiled, used as fertilizer, and a source of direct contamination in the Great Pee Dee River/Winyah Bay watershed, it is very likely the source of the Bacteroides that was deposited on the marsh. The mid-points of the core sections were dated as follows: 0–3 cm, 2009; 9–12 cm, 1999, and 30–33 cm, 1961. The presence of Bacteroides at different depths/ages in the soil profile indicates that soils in tidal freshwater marshes are, at the least, capable of being short-term sinks for Bacteroides and, may have the potential to be long-term sinks of stable, naturalized populations.

Soil pollution with trace elements is a growing problem with serious environmental impacts and developing strategies to reduce those impacts is a high priority. The objectives of this study were to assess the role of sulfur (S) in reducing the phytotoxic effects of copper (Cu) and the appearance of oxidative stress due to excess Cu in the growth medium and to assess the potential of guinea grass for Cu phytoremediation. The experiment was carried out in a greenhouse, where the forage grass Panicum maximum cv. Tanzânia was grown with a nutrient solution containing combinations of three S concentrations (0.1, 2, and 4 mmol L⁻¹) and four Cu concentrations (0.3, 100, 500, and 1,000 μmol L⁻¹) using a 3 × 4 factorial design in complete randomized blocks with four replicates. The following variables were measured: shoot and root dry mass production, leaf and tiller number, S and Cu concentrations in diagnostic leaves and roots, H₂O₂, lipid peroxidation, and proline levels in the diagnostic leaves. Very high Cu availability (1,000 μmol L⁻¹) that resulted in Cu concentration higher than 60 mg kg⁻¹in diagnostic leaves caused more than 50 % reduction in shoot and root dry mass production about 30–40 % in the number of leaves and tillers around 20 % increase in lipid peroxidation and more than 10 times increase in proline production. Plants properly fed with S showed mitigation to Cu toxicity. Guinea grass showed promise as an agent in the phytoremediation of Cu-polluted areas.

This study evaluates the degree of pollution of marine sediments using two methods: standard (physico-chemical parameters) and instrumental techniques: thermogravimetric analysis (TG) and infrared spectroscopy (ATR-FTIR). ATR-FTIR proved to be a tool capable of identifying the organic and inorganic compounds in sediments such as organic carbon, clay, and carboxylate groups which can bind metal contaminants. TG results of 14 sediment samples were compared with organic matter (OM), organic carbon (OC), total nitrogen (TN), clay, and carbonate (CaCO₃) contents obtained by standard methods. The results showed that weight losses for a specific range of temperatures are closely correlated with the content of OM (R ² = 0.92), OC (R ² = 0.82), TN (R ² = 0.96), clay content (R ² = 0.87), and CaCO₃ (R ² = 0.9) for sediment samples. It is concluded that TG and ATR-FTIR allows a simultaneous, rapid, and reliable screening of sediment properties.

Zn²⁺was added to one of the two identical bench-scale upflow anaerobic sludge blanket (UASB) reactors in steady-state period treating swine wastewater to evaluate the effects of Zn²⁺on performance and methanogenic population. Real-time quantitative PCR (QPCR) was used to quantify the 16S rRNA gene concentrations of the four methanogenic orders. In both reactors, the hydraulic retention time (HRT) was sustained at 48 h and the inner temperature was kept at 35 °C. Both promotion and inhibition of Zn²⁺on chemical oxygen demand (COD) removal, methane production and methanogens community were observed in accordance with different Zn²⁺dosages. COD removal rate and methane production reacted in the same way as methanogens, suggesting that the impact of Zn²⁺on the methanogenic community was the critical reason that caused the changes of UASB performance in treating swine wastewater with unstable Zn²⁺concentration. Among the methanogenic community, Methanomicrobiales (MMB) was the dominant group which got visibly impacted by the dosed Zn²⁺. Overall, lower concentration of Zn²⁺, e.g., less than 17.8 mg/L, was supposed to be advisable for a stable and high efficient treatment of swine wastewater by UASB reactor in practice.

Petroleum hydrocarbons are among the most important contaminants in aquatic ecosystems, but the effects of different petroleum components on the archaeal communities in these environments are still poorly investigated. Therefore, the effects of representative alkanes, polycyclic aromatic hydrocarbons and crude oil on archaeal communities from marine (Massambaba Beach) and hypersaline waters (Vermelha Lagoon) from the Massambaba Environmental Protection Area, Rio de Janeiro, Brazil, were examined in this study. Hydrocarbon contamination was simulated in vitro, and the resulting microcosms were temporally analyzed (4, 12 and 32 days after contamination) using molecular methods. DNA and RNA extractions were followed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analyses and by the further molecular identification of selected DGGE bands. Archaeal communities could not be detected in the marine microcosms after contamination with the different hydrocarbons. In contrast, they were detected by DNA- and RNA-based methods in hypersaline water. Dendrogram analyses of PCR-DGGE showed that the archaeal communities in the hypersaline water-derived microcosms selected for by the addition of heptadecane, naphthalene or crude oil differed from the natural ones observed before the hydrocarbon contaminations. Principal coordinate analysis of the DGGE patterns showed an important effect of incubation time on the archaeal communities. A total of 103 DGGE bands were identified, and phylogenetic analysis showed that 84.4 % and 15.5 % of these sequences were associated with the Euryarchaeota and Crenarchaeota groups, respectively. Most of the sequences obtained were related to uncultivated archaea. Using redundancy analysis, the response of archaeal communities to the type of hydrocarbon contamination used could also be observed in the hypersaline water-derived microcosms.

In this study, zinc oxide was immobilized on magnetite nanoparticles by chemical method and it was used as an adsorbent to remove reactive black 5 (RB5) dye from aqueous solution. The removal efficiency of RB5 was studied as the function of adsorbent dosage, pH, initial RB5 concentration, H₂O₂, and ionic strength (sodium carbonate, sodium bicarbonate, sodium sulfate, and sodium chloride). Removal efficiency of RB5 by ZnO–Fe₃O₄ was greater than that by ZnO and Fe₃O₄ in similar conditions. Maximum adsorption of ZnO–Fe₃O₄ was obtained at neutral pH, and adsorption capacity was estimated to be 22.1 mg/g. Adsorption kinetic study revealed that the pseudo-second-order model better described the removal rate than the pseudo-first-order model. Adsorption isotherm was analyzed by both Langmuir and Freundlich equations, and results showed that it was better described by the Langmuir equation. The removal efficiency of RB5 was increased with increasing initial H₂O₂ concentrations from 2 to 5 mM but was decreased above 5 mM. The adsorption capacities of RB5 was increased in the presence of NaCl but was greatly decreased in the presence of bicarbonate, carbonate, and sulfate ion. Adsorption activity of RB5 by ZnO–Fe₃O₄ composite was maintained even after five successive cycles, suggesting a promising adsorbent for wastewater-contaminated organic dyes.

Natural resource habitats, which are isolated from the surface water bodies, are often unregulated and face a higher risk of degradation. Vernal pools, habitats for amphibians, are vulnerable to external stressors that often lead to decline in biodiversity. There is a need to protect these through conservation measures at a spatially targeted level. This study is conducted in the Middle Connecticut River Watershed of Massachusetts State. We evaluate the risk faced by isolated vernal pools at the subwatershed scale. The assessment involves the impact of agricultural intensity and vernal pool distribution in proximity to agriculture parcels. This is performed using geoprocessing techniques within a geographic information system (GIS). The spatial data are used in a nonlinear regression model to evaluate potential stressors to vernal pool existence. The model included land use, geographic features, and hydrographic factors. Agriculture and open land positively influence vernal pool existence, because of vernal pool association with low-lying areas. In addition, elevation showed a negative influence on the number of vernal pool habitats. The results of the spatial risk evaluation of habitat are helpful to target efforts on specific subwatersheds in conserving vernal pool habitats.

Recent scientific findings and legislations have clearly highlighted the need for comprehensive approaches and methods to evaluate natural dust contributions to an urban atmosphere. The evaluation of chemical compositions of airborne aerosols is of these methods that may employ several advanced analytical techniques and processes. In this paper, an episodic appearance of Saharan dust incursion over a megacity (Istanbul, Turkey) was investigated using size segregated particulate matter (PM) samples in fine and coarse fractions collected between February 27 and March 8, 2009. The Saharan impact was investigated using satellite observations, backward air trajectory statistics, and chemical analyses of the collected samples. In the chemical analyses, Fourier transform infrared coupled with attenuated total reflectance (ATR-FTIR) spectroscopic method was used to determine the functional groups, namely, alcohols, ammonium, aliphatic carbons, carbonyls, organonitrates, nitrate, silicate, silica, kaolinite, and calcium carbonate. Among all the measured functional groups, it was clearly seen that the intensities of IR peaks related to silicate, silica, kaolinite, and calcium carbonate were associated with the increased mass concentrations during the impact period. The observed IR peaks at 1,030 and 800 cm⁻¹for silicate ions in the samples can be used as an indicator of the large dust incursion into the atmosphere (e.g., Saharan dust episodes observed in Istanbul). This study showed that the ATR-FTIR spectroscopic method is a fast and convenient method to identify these peaks and the IR method in general is useful for identifying a large dust incursion into the atmosphere.

Biodiesel has proven to be a reasonable substitute to petroleum diesel owing to continuous depletion and pollution caused by the latter. The uncomplicated process of production of fatty acid methyl ester or biodiesel as it is commercially known has made it an even better substitute of fossil diesel. The preparation of biodiesel involves the use of alcohol (methanol) and hydroxides (NaOH). There is a possibility that some of these compounds remain unreacted and needs to be washed with water. This residue water containing alcohol and hydroxide residues if discharged in the soil may affect its quality. This research paper deals with the effect of biodiesel effluent on various physico-chemical properties of soil. The result of the research proves that the biodiesel effluent if discharged in soil will degrade soil quality.