Revealing archaeal diversity patterns and methane fluxes in Admiralty Bay, King George Island, and their association to Brazilian Antarctic Station activities

The study of Antarctic archaeal communities adds information on the biogeography of this group and helps understanding the dynamics of biogenic methane production in such extreme habitats. Molecular methods were combined to methane flux determinations in Martel Inlet, Admiralty Bay, to assess archaeal diversity, to obtain information about contribution of the area to atmospheric methane budget and to detect possible interferences of the Antarctic Brazilian Station Comandante Ferraz (EACF) wastewater discharge on local archaeal communities and methane emissions. Methane fluxes in Martel Inlet ranged from 3.2 to 117.9 mu mol CH(4) m(-2) d(-1), with an average of 51.3 +/- 8.5 mu mol CH(4) m(-2) d(-1) and a median of 57.6 mu mol CH(4) m(-2)d(-1). However, three negative fluxes averaging -11.3 mu mol CH(4) m(-2) d(-1) were detected in MacKellar Inlet, indicating that Admiralty Bay can be either a source or sink of atmospheric methane. Denaturing gradient gel electrophoresis (DGGE) showed that archaeal communities at EACF varied with depth and formed a group separated from the reference sites. Granulometric analysis indicated that differences observed may be mostly related to sediment type. However, an influence of wastewater input could not be discarded, since higher methane fluxes were found at CF site. suggesting stimulation of local methanogenesis. DGGE profile of the wastewater sample grouped separated from all other samples, suggesting that methanogenesis stimulation may be due to changes in environmental conditions rather than to the input of allochtonous species from the wastewater. 16S ribosomal DNA clone libraries analysis showed that all wastewater sequences were related to known methanogenic groups belonging to the hydrogenotrophic genera Methanobacterium and Methanobrevibacter and the aceticlastic genus Methanosaeta. EACF and Botany Point sediment clone libraries retrieved only groups of uncultivated Archaea, with predominance of Crenarchaeota representatives (MCG, MG1, MBG-B, MBG-C and MHVG groups). Euryarchaeota sequences found were mostly related to the LDS and RC-V groups, but MBG-D and DHVE-5 were also present. No representatives of cultivated methanogenic groups were found, but coverage estimates suggest that a higher number of clones would have to be analyzed in order to cover the greater archaeal diversity of Martel Inlet sediment. Nevertheless, the analysis of the libraries revealed groups not commonly found by other authors in Antarctic habitats and also indicated the presence of groups of uncultivated archaea previously associated to methane rich environments or to the methane cycle. (C) 2010 Elsevier Ltd. All rights reserved.

Optimization of in situ derivatization SPME by experimental design for GC-MS multi-residue analysis of pharmaceutical drugs in wastewater

This paper presents the development of a procedure, which enables the analysis of nine pharmaceutical drugs in wastewater using gas chromatography-mass spectrometry (GC-MS) associated with solid-phase microextraction (SPME) for the sample preparation. Experimental design was applied to optimize the in situ derivatization and the SPME extraction conditions. Ethyl chloroformate (ECF) was employed as derivatizing agent and polydimethylsiloxane-divinylbenzene (PDMS-DVB) as the SPME fiber coating. A fractional factorial design was used to evaluate the main factors for the in situ derivatization and SPME extraction. Thereafter, a Doehlert matrix design was applied to find out the best experimental conditions. The method presented a linear range from 0.5 to 10 mu g/L, and the intraday and interday precision were lower than 16%. Applicability of the method was verified from real influent and effluent samples of a wastewater treatment plant, as well as from samples of an industry wastewater and a river.

Distribution of sewage input in marine sediments around a maritime Antarctic research station indicated by molecular geochemical indicators

Sediments from Admiralty Bay, Antarctica were collected during the austral summers of 2002/2003 and 2003/2004 in order to assess the distribution and concentration of sewage indicators originating from Comandante Ferraz Brazilian Antarctic Station. Fecal sterols (coprostanol + epicoprostanol) and linear alkylbenzenes (LABs) ranged from <0.01 to 0.95 mu g g(-1) and <1.0 to 23 ng g(-1) dry weight, respectively. In general, the higher concentrations were found only locally in the vicinity of Ferraz station at Martel Inlet. Baseline values for fecal sterols and coprostanone were calculated as 0.19 and 0.40 mu g g(-1), respectively. According to fecal sterols concentrations, sewage contribution to Martel Inlet has increased more than twice since 1997, as result of the increase in the number of researchers at the station especially during the last decade. A low correlation was found between total LABs and fecal steroids, which could be attributed to the contribution of the natural sources of steroids. (C) 2010 Elsevier B.V. All rights reserved.

Characterization of Immobilized Biomass by Amplified rDNA Restriction Analysis (ARDRA) in an Anaerobic Sequencing-Batch Biofilm Reactor (ASBBR) for the Treatment of Industrial Wastewater

The performance of an anaerobic sequencing-batch biofilm reactor (ASBBR-laboratory scale- 14L) containing biomass immobilized on coal was evaluated for the removal of elevated concentrations of sulfate (between 200 and 3,000 mg SO4-2.L-1) from industrial wastewater effluents. The ASBBR was shown to be efficient for removal of organic material (between 90% and 45%) and sulfate (between 95% and 85%). The microbiota adhering to the support medium was analyzed by amplified ribosomal DNA restriction analysis (ARDRA). The ARDRA profiles for the Bacteria and Archaea domains proved to be sensitive for the determination of microbial diversity and were consistent with the physical-chemical monitoring analysis of the reactor. At 3,000 mg SO4-2.L-1, there was a reduction in the microbial diversity of both domains and also in the removal efficiencies of organic material and sulfate.

Evaluation of the Sensitivity of Freshwater Organisms Used in Toxicity Tests of Wastewater from Explosives Company

Explosives industries are a source of toxic discharge. The aim of this study was to compare organisms sensitivity (Daphnia similis, Danio rerio, Escherichia coli and Pseudomonas putida) in detecting acute toxicity in wastewater from two explosives, 2,4,6-TNT (TNT) and nitrocellulose. The samples were collected from an explosives company in the Paraiba Valley, So Paulo, Brazil. The effluents from TNT and nitrocellulose production were very toxic for tested organisms. Statistical tests indicated that D. similis and D. rerio were the most sensitive organisms for toxicity detection in effluents from 2,4,6-TNT and nitrocellulose production. The P. putida bacteria was the organism considered the least sensitive in indicating toxicity in effluents from nitrocellulose.

Homogeneity assessment of a station climate series (1933-2005) in the Metropolitan Area of Sao Paulo: instruments change and urbanization effects

This work assessed homogeneity of the Institute of Astronomy, Geophysics and Atmospheric Sciences (IAG) weather station climate series, using various statistical techniques. The record from this target station is one of the longest in Brazil, having commenced in 1933 with observations of precipitation, and temperatures and other variables later in 1936. Thus, it is one of the few stations in Brazil with enough data for long-term climate variability and climate change studies. There is, however, a possibility that its data may have been contaminated by some artifacts over time. Admittedly, there was an intervention on the observations in 1958, with the replacement of instruments, for which the size of impact has not been yet evaluated. The station transformed in the course of time from rural to urban, and this may also have influenced homogeneity of the observations and makes the station less representative for climate studies over larger spatial scales. Homogeneity of the target station was assessed applying both absolute, or single station tests, and tests relatively to regional climate, in annual scale, regarding daily precipitation, relative humidity, maximum (TMax), minimum (TMin), and wet bulb temperatures. Among these quantities, only precipitation does not exhibit any inhomogeneity. A clear signal of change of instruments in 1958 was detected in the TMax and relative humidity data, the latter certainly because of its strong dependence on temperature. This signal is not very clear in TMin, but it presents non-climatic discontinuities around 1953 and around 1970. A significant homogeneity break is found around 1990 for TMax and wet bulb temperature. The discontinuities detected after 1958 may have been caused by urbanization, as the observed warming trend in the station is considerably greater than that corresponding to regional climate.

The Compositional Aesthetic of Rodolfo Coelho de Souza in Paradise Station: an analysis

This article focuses on the compositional aesthetics of Rodolfo Coelho de Souza (1952-), a Brazilian fine art composer and active researcher, whose concerns surpasses the musical composition isolated from the social communication aspect. This is particularly evident in his piece Paradise Station, which, when analyzed, features the structural depth of its compositional process without disregarding the dialog with the listener and the Brazilian character, according to pitch, rhythm, texture, timbre and dynamics. The present analysis reveals a modular structure based on set classes, worked through a transformation network, which follows the David Lewin model.

Predation of Caiman yacare (Spix, 1825) (Crocodilia, Alligatoridae) by Busarellus nigricollis (Latham, 1790) (Accipitriformes, Accipitridae) in the Taiama Ecological Station, Alto Pantanal, State of Mato Grosso

Predation of Caiman yacare (Spix, 1825) (Crocodilia, Alligatoridae) by Busarellus nigricollis (Latham, 1790) (Accipitriformes, Accipitridae) in the Taiama Ecological Station, Alto Pantanal, State of Mato Grosso. The Black-collared Hawk Busarellus nigricollis is an Accipitridae commonly seen on river banks, lagoon shores, and marshy areas. It feeds mainly on fishes and aquatic insects. It hunts from dead tree branches at forest edges or emergent trunks in flooded areas. Detailed information about the Black-collared Hawk food habits is scarce. In this study, we describe the predation of Caiman yacare (Pantanal alligator) by an individual of B. nigricollis. The event was observed on 20 August 2010 at 10: 14 am, in the Taiama Ecological Station, municipality of Caceres, Alto Pantanal, state of Mato Grosso. The B. nigricollis individual was seen leaving the Paraguay River carrying a juvenile C. yacare around 40 cm long. The prey was torn apart and given to a Black-collared Hawk nestling sitting atop a nest in flooded forest, ca. 15 m way from the river bank. This is the first published record of Pantanal alligator predation by the Black-collared Hawk.

Spin coherence generation in negatively charged self-assembled (In,Ga)As quantum dots by pumping excited trion states

Spin coherence generation in an ensemble of negatively charged (In,Ga)As/GaAs quantum dots was investigated by picosecond time-resolved pump-probe spectroscopy measuring ellipticity. Robust coherence of the ground-state electron spins is generated by pumping excited charged exciton (trion) states. The phase of the coherent state, as evidenced by the spin ensemble precession about an external magnetic field, varies relative to spin coherence generation resonant with the ground state. The phase variation depends on the pump photon energy. It is determined by (a) pumping dominantly either singlet or triplet excited states, leading to a phase inversion, and (b) the subsequent carrier relaxation into the ground states. From the dependence of the precession phase and the measured g factors, information about the quantum dot shell splitting and the exchange energy splitting between triplet and singlet states can be extracted in the ensemble.

Advanced oxidation process H2O2/UV combined with anaerobic digestion to remove chlorinated organics from bleached kraft pulp mill wastewater

This study investigated the application of an advanced oxidation process combining hydrogen peroxide with ultraviolet radiation (H2O2/UV) to remove recalcitrant compounds from Kraft bleaching effluent. Anaerobic pre-treatment was performed to remove easily degraded organics using a horizontal-flow anaerobic immobilized biomass (HAIB) reactor. Bleaching plant effluent was treated in the HAIB reactor processed over 19 h of hydraulic retention time (HRT), reaching the expected removal efficiencies for COD (61 +/- 3%), TOC (69 +/- 9%), BOD5 (90 +/- 5%) and AOX (55 +/- 14%). However, the anaerobic treatment did not achieve acceptable removal of UV254 compounds. Furthermore, there was an increase of lignin, measured as total phenols. The H2O2/UV post-treatment provided a wide range of removal efficiencies depending on the dosage of hydrogen peroxide and UV irradiation: COD ranged from 0 to 11%, UV254 from 16 to 35%, lignin from 0 to 29% and AOX from 23 to 54%. All peroxide dosages applied in this work promoted an increase in the BOD5/COD ratio of the wastewater. The experiments demonstrate the technical feasibility of using H2O2/UV for post-treatment of bleaching effluents submitted to anaerobic pre-treatment.

Application of Electrochemical Degradation of Wastewater Composed of Mixtures of Phenol-Formaldehyde

The industrial wastewater from resin production plants contains as major components phenol and formaldehyde, which are traditionally treated by biological methods. As a possible alternative method, electrochemical treatment was tested using solutions containing a mixture of phenol and formaldehyde simulating an industrial effluent. The anode used was a dimensionally stable anode (DSAA (R)) of nominal composition Ti/Ru0.3Ti0.7O2, and the solution composition during the degradation process was analyzed by liquid chromatography and the removal of total organic carbon. From cyclic voltammetry, it is observed that for formaldehyde, a small offset of the beginning of the oxygen evolution reaction occurs, but for phenol, the reaction is inhibited and the current density decreases. From the electrochemical degradations, it was determined that 40 mA cm(-2) is the most efficient current density and the comparison of different supporting electrolytes (Na2SO4, NaNO3, and NaCl) indicated a higher removal of total organic carbon in NaCl medium.

Ecotoxicological evaluation of wastewater from 2.4.6-TNT production

During the manufacture of explosives, large amounts of water are used to remove unwanted by-products generated. This water in turn, ends up in wastewater treatment plants or water bodies. The aim of this study was to evaluate the toxic potential of effluent generated by 2.4.6-Trinitrotoluene (TNT) production, yellow water, red water and mixture of yellow and red water, produced from a plant located in the Paraiba Valley, Sao Paolo state, Brazil. Daphnia similis, Danio rerio, Escherichia coli, Pseudomonas putida and Pseudokircheneriella subcaptata were used as test organisms. Physicochemical parameters such as color, pH, conductivity, total dissolved solids, dissolved oxygen, chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were evaluated. Effluent from 2.4.6-TNT production was extremely toxic to all test organisms. The physicochemical parameters evaluated showed high levels of conductivity (from 41.533 to 42.344 mu S /cm) and chemical oxygen demand (COD of 8471 to 27.364 mg/L) for the effluents analyzed.

Nutrients and Nonessential Elements in Soil after 11 Years of Wastewater Irrigation

Irrigation of citrus (Citrus aurantium L. x Citrus paradise Macf.) with urban reclaimed wastewater (RWW) can be economical and conserve fresh water. However, concerns remain regarding its deleterious effects on soil quality. We investigated the ionic speciation (ISP) of RWW and potential impacts of 11 yr of irrigation with RWW on soil quality, compared with well-water (WW) irrigation. Most of nutrients (similar to 53-99%) in RWW are free ionic species and readily available for plant uptake, such as: NH4+, NO3-, K+, Ca2+, Mg2+, SO42-, H3BO3, Cl-, Fe2+, Mn2+, Zn2+, Co2+, and Ni2+, whereas more than about 80% of Cu, Cr, Pb, and Al are complexed with CO3-, OH-, and/or organic matter. The RWW irrigation increased the availability and total concentrations of nutrients and nonessential elements, and soil salinity and sodicity by two to three times compared with WW-irrigated soils. Although RWW irrigation changed many soil parameters, no difference in citrus yield was observed. The risk of negative impacts from RWW irrigation on soil quality appears to be minimal because of: (i) adequate quality of RWW, according to USEPA limits; (ii) low concentrations of metals in soil after 11 yr of irrigation with RWW; and (iii) rapid leaching of salts in RWW-irrigated soil during the rainy season.

Parasitological risk assessment from wastewater reuse for disposal in soil in developing countries

The purpose of this work is to analyze the parasitological risks of treated wastewater reuse from a stabilization pond in the city of Piracicaba, in the State of Sao Paulo (Brazil), and the level of treatment required to protect public health. Samples were taken from raw and treated wastewater in stabilization ponds and submitted to a parasitological, microbiological and physicochemical analysis. The study revealed on treated wastewater the presence of Ascaris sp. and Entamoeba coli with an average density of 1 cysts L-1 and 6 eggs L-1, respectively. For Ascaris, the annual risks of infection due to the accidental ingestion of wastewater irrigation were 7.5 x 10(-2) in 208 days and 8.7 x 10(-2) in 240 days. For Total Coliforms and Escherichia coli in treated wastewater, the average density was 1.0 x 10(5) MPN/100 ml and 2.7 x 10(4) MPN/100 ml respectively, representing 99% and 94% removal efficiency, respectively. For BOD, COD, TS and TSS removal efficiency was 69, 80, 50 and 71%, respectively. The removal efficiency for nitrogen; ammonia nitrogen and total phosphate was 24, 19 and 68%, respectively. The average density of helminths eggs in treated wastewater is higher compared to the density of the limit value of <= 1 egg L-1 and tolerable risk is above the level recommended by the World Health Organization. Multiple barriers are necessary for the reduction of organic matter, chemical contaminants and parasites from treated wastewater. Standards for the sanitary control of treated wastewater to be reused in agricultural irrigation areas should be compiled for developing countries in order to minimize public health risks.

Characterization of immobilized biomass by amplified rDNA restriction analysis (ARDRA) in an anaerobic sequencing-batch biofilm reactor (ASBBR) for the treatment of industrial wastewater

The performance of an anaerobic sequencing-batch biofilm reactor (ASBBR- laboratory scale- 14L )containing biomass immobilized on coal was evaluated for the removal of elevated concentrations of sulfate (between 200 and 3,000 mg SO4-2·L-1) from industrial wastewater effluents. The ASBBR was shown to be efficient for removal of organic material (between 90% and 45%) and sulfate (between 95% and 85%). The microbiota adhering to the support medium was analyzed by amplified ribosomal DNA restriction analysis (ARDRA). The ARDRA profiles for the Bacteria and Archaea domains proved to be sensitive for the determination of microbial diversity and were consistent with the physical-chemical monitoring analysis of the reactor. At 3,000 mg SO4-2·L-1, there was a reduction in the microbial diversity of both domains and also in the removal efficiencies of organic material and sulfate.