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2.
J Environ Manage ; 261: 109907, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148249

RESUMO

The Mediterranean aquaculture has been developed mostly in brackish environment in inactive coastal salt production areas. This study aims to utilise Technosols made with aquaculture sediments for Limonium algarvense Erben cultivation. This species that has nutraceutical potential thrives in halophilic environments in the southwest of the Iberian Peninsula and in Morocco. A microcosm assay was set up with plants grown in bottom sediments (C+), commercial substrate (C-), and Technosols with amendments mixture application at 180 g/kg (Tec180) or at 360 g/kg (Tec360). These plants were irrigated with saline (assay 1) and/or with deionised water (assay 2). The bottom pond sediments, coffee wastes and the estuarine water were evaluated for diverse physicochemical parameters. Plant growth was characterised through a combined methodology using morphometric, SEM and physiological analysis. The Technosols were constructed with bottom sediments and a mixture of organic wastes used as amendments. Results revealed that the bottom sediments had low pH 3.2, Corg and extractable P and K contents, and high electroconductivity (EC) and N-NH4 concentration. The estuarine water had a neutral pH, high EC and high Cl-, HCO3-, Na+, Mg2+ and Ca2+ but low N-NO3- content. The Technosols showed a significant increase of pH, Corg, K and P and a decrease in N-NH4 and EC in comparison with sediments. Principal component analysis separated the different experiments in three groups: C-, A1 and A2 assays. The C- was highly correlated with Corg, P, K, N-NO3 parameters and total ascorbate. The A1 assay showed a strong association with Na, Ca and EC parameters, whereas the A2 assay presented a strongly correlation with plant growth. Plants from Technosols had greater development when irrigated with deionised water than under salty irrigation as opposed to plants cultivated in unamend sediments. In conclusion, these results support that highly saline sediments could be valorised through Technosols construction to cultivate plants with saline water, with potential application in the agro-food and pharmaceutical industry.


Assuntos
Tanques , Plantas Tolerantes a Sal , Aquicultura , Sedimentos Geológicos , Marrocos , Águas Salinas
3.
J Environ Manage ; 261: 110244, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148311

RESUMO

On-line performance indicators of a microalgae-bacteria consortium were screened out from different variables based on pH and dissolved oxygen on-line measurements via multivariate projection analysis, aiming at finding on-line key state indicators to easily monitor the process. To fulfil this objective, a pilot-scale high-rate pond for urban wastewater treatment was evaluated under highly variable conditions, i.e. during the start-up period. The system was started-up without seed of either bacterial or microalgal biomass. It took around 19 days to fully develop a microalgal community assimilating nutrients significantly. Slight increases in the biomass productivities in days 26-30 suggest that the minimum time for establishing a performant bacteria-microalgae consortium could be of around one month for non-inoculated systems. At this point, the process was fully functional, meeting the European discharge limits for protected areas. The results of the statistical analyses show that both the pH and the dissolved oxygen concentration represent accurately the biochemical processes taking place under the start-up of the process. Both pH and dissolved oxygen represented accurately also the performance of the high-rate algal pond, being affordable, easily-implemented, options for monitoring, control and optimization of industrial-scale processes.


Assuntos
Microalgas , Bactérias , Biomassa , Tanques , Eliminação de Resíduos Líquidos , Águas Residuárias
4.
J Environ Radioact ; 214-215: 106152, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32063284

RESUMO

Luminescence dosimetry was performed using bricks from the former settlement of Metlino, Southern Urals, Russia, to investigate the feasibility of validating the Techa River Dosimetry System (TRDS) 2016 for the shore of the Metlinsky Pond, upper Techa River region. TRDS is a code for estimating external and internal doses for members of the Extended Techa River Cohort. Several brick samples were taken from the north-western wall of the granary, facing the Metlinsky Pond. Samples were measured at different heights and at different depths into the bricks. Dating of the granary was performed by analyzing well shielded bricks. Assessment of the gamma dose-rate at the sample positions was done by thermoluminescent dosimeters and the dose-rate in front of the granary mapped with a dose-rate meter. Anthropogenic doses in bricks vary from 0.8 to 1.7 Gy and show an increase with sampling height. A similar height profile is observed for the current gamma dose-rate, which is compatible with the results of the dose-rate mapping. Implications for validating the TRDS are discussed.


Assuntos
Tanques , Monitoramento de Radiação , Estudos de Viabilidade , Luminescência , Federação Russa , Poluentes Radioativos da Água
5.
Microbes Environ ; 35(1)2020.
Artigo em Inglês | MEDLINE | ID: mdl-32037377

RESUMO

Although the bioavailability of rare earth elements (REEs, including scandium, yttrium, and 15 lanthanides) has not yet been examined in detail, methane-oxidizing bacteria (methanotrophs) were recently shown to harbor specific types of methanol dehydrogenases (XoxF-MDHs) that contain lanthanides in their active site, whereas their well-characterized counterparts (MxaF-MDHs) were Ca2+-dependent. However, lanthanide dependency in methanotrophs has not been demonstrated, except in acidic environments in which the solubility of lanthanides is high. We herein report the isolation of a lanthanide-dependent methanotroph from a circumneutral environment in which lanthanides only slightly dissolved. Methanotrophs were enriched and isolated from pond sediment using mineral medium supplemented with CaCl2 or REE chlorides. A methanotroph isolated from the cerium (Ce) chloride-supplemented culture, Methylosinus sp. strain Ce-a6, was clearly dependent on lanthanide. Strain Ce-a6 only required approximately 30 nM lanthanide chloride for its optimal growth and exhibited the ability to utilize insoluble lanthanide oxides, which may enable survival in circumneutral environments. Genome and gene expression analyses revealed that strain Ce-a6 lost the ability to produce functional MxaF-MDH, and this may have been due to a large-scale deletion around the mxa gene cluster. The present results provide evidence for lanthanide dependency as a novel survival strategy by methanotrophs in circumneutral environments.


Assuntos
Genoma Bacteriano/genética , Elementos da Série dos Lantanídeos/metabolismo , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Oxirredutases do Álcool/genética , Proteínas de Bactérias/genética , Meios de Cultura/metabolismo , Sedimentos Geológicos/microbiologia , Metais Terras Raras/metabolismo , Metano/metabolismo , Methylosinus/classificação , Methylosinus/genética , Methylosinus/isolamento & purificação , Methylosinus/metabolismo , Tanques/microbiologia , Proteobactérias/classificação , Proteobactérias/fisiologia , RNA Ribossômico 16S/genética
6.
Bioresour Technol ; 304: 123021, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32086031

RESUMO

The present study aimed to enhance the biomethanation potential of mixed microalgae via cost effective surfactant coupled ultrasonic homogenization (SCUH). Mixed microalgae biomass was harvested using a coagulant (Alum) from a raceway pond. The harvested algal biomass was subjected to ultrasonic homogenization (UH) by varying the power from 100 to 180 W. A maximal soluble organic release of 2131 mg/L was achieved at an ultrasonic input energy (UIE) of 25200 kJ/kg TS. In order to enhance soluble organic release and to reduce energy spent, the optimized condition of ultrasonic pretreatment was coupled with varying sodium dodecyl sulphate (SDS) dosage. A higher solubilization of 30.5% was achieved at a UIE of 4200 kJ/kg SS with surfactant dosage of 0.02 g SDS/g SS for SCUH. SCUH showed higher methane production of 358 mL/g COD when compared to UH (185.9 mL/g COD), SCUH was economically feasible than UH.


Assuntos
Microalgas , Anaerobiose , Biomassa , Metano , Tanques , Tensoativos , Ultrassom
7.
Appl Microbiol Biotechnol ; 104(5): 2229-2241, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31915903

RESUMO

The aquatic microbial community is sensitive to environmental change; however, the impacts of those changes combined with disease outbreaks affecting S. paramamosain are unknown. Thus, from March to October, we explored the interaction between aquacultural environmental conditions and microbial composition and function in open-air aquaculture ponds containing S. paramamosain in Southern China. The microbial community structure was significantly positively correlated with microbial community function. The environment variables such as temperature and salinity during May and June changed more quickly compared with other periods, resulting changes in the structure and function of the microbial community affected S. paramamosain survivability, with higher crab mortality observed from May to June compared with other periods. These included changes in the relative abundance of Microtrichales, Synechococcales, Rhodobacterales, Chitinophagales, and SAR11_clade, and corresponding functions associated with glycolysis and/or gluconeogenesis, porphyrin and chlorophyll metabolism, photosynthetic proteins, and transcription factors. These changes could impact S. paramamosain mortality and be used to evaluate the health status of the ponds. Though the environment variables during July~October changed slowly comparing to May and June, the ponds microflora changed which benefit S. paramamosain survivability with correspondingly low S. paramamosain mortality. Therefore, rapid environmental change alters the structure and function of the aquatic microflora, increasing S. paramamosain mortality.


Assuntos
Braquiúros/fisiologia , Microbiota , Tanques/microbiologia , Microbiologia da Água , Animais , Aquicultura , China , Monitoramento Ambiental , Microbiota/genética , Nutrientes/análise , Tanques/química , Salinidade , Estações do Ano , Temperatura Ambiente
8.
Bioresour Technol ; 301: 122672, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31945681

RESUMO

The objective of this study was to evaluate the performance of an outdoor membrane-coupled high-rate algal pond equipped with industrial-scale membranes for treating urban wastewater. Decoupling biomass retention time (BRT) and hydraulic retention time (HRT) by membrane filtration resulted in improved process efficiencies, with higher biomass productivities and nutrient removal rates when operating at low HRTs. At 6 days of BRT, biomass productivity increased from 30 to 66 and to 95 g·m-3·d-1 when operating at HRTs of 6, 4 and 2.5 days, respectively. The corresponding nitrogen removal rates were 4, 8 and 11 g N·m-3·d-1 and the phosphorous removal rates were 0.5, 1.3 and 1.6 g P·m-3·d-1. The system was operated keeping moderate specific air demands (0.25 m3·m-2·h-1), resulting in reasonable operating and maintenance costs (€0.04 per m3) and energy requirements (0.29 kWh per m3). The produced water was free of pathogens and could be directly used for reusing purposes.


Assuntos
Águas Residuárias , Purificação da Água , Biomassa , Nitrogênio , Tanques , Eliminação de Resíduos Líquidos
9.
Environ Sci Technol ; 54(4): 2091-2102, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31976664

RESUMO

Microalgae have great potential as an energy and feed resource. Here we evaluate the water use associated with freshwater algae cultivation and find it is possible to scale U.S. algae biofuel production to 20.8 billion liters of renewable diesel annually without significant water-stress impact. Among potential sites, water-stress is significantly more variable than algae productivity across location and season. Thus, it is possible to reduce water-stress impact, quantified as water scarcity footprint, through the choice of algae site location. We test three site-selection criteria based on (1) biomass productivity, (2) water-use efficiency, and (3) water-stress impact and find that adding water-stress constraints to productivity-based ranking of suitable sites reduces water-stress impact by 97% and water consumption by half, compared with biomass-productivity ranking alone, with little productivity impact (<1.7% per-site on average). With 20.8 billion liters, algae could meet 19.7% of U.S. jet fuel demand with a freshwater demand of less than 1.4% of U.S. irrigation consumption. Evaluating water-stress impact is important because the impact of unit water consumption on water stress varies significantly across regions and seasons. Considering seasonal water balances allows producers to understand the combined seasonal effects of hydrologic flows and productivity, thereby avoiding potential short-term water stress.


Assuntos
Microalgas , Biocombustíveis , Biomassa , Desidratação , Humanos , Tanques , Estações do Ano
10.
Environ Sci Technol ; 54(5): 2790-2799, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-31995355

RESUMO

Distinguishing between naphthenic acids (NAs) associated with oil sands process-affected water (OSPW) and those found naturally in groundwaters in contact with the bituminous McMurray Formation poses a considerable analytical challenge to environmental research in Canada's oil sands region. Previous work addressing this problem combined high-resolution Orbitrap mass spectrometry with carbon isotope values generated by online pyrolysis (δ13Cpyr) to characterize and quantify the acid extractable organics (AEOs) fraction containing NAs in the subsurface near an oil sands tailings pond. Here, we build upon this work through further development and application of these techniques at two different study sites near two different tailings ponds, in conjunction with the use of an additional isotopic tool-sulfur isotope analysis (δ34S) of AEOs. The combined use of both δ13Cpyr and δ34S allowed for discrimination of AEOs into the three end-members relevant to ascertaining the NA environmental footprint within the region: (1) OSPW; (2) McMurray Formation groundwater (i.e., naturally occurring bitumen), and; (3) naturally occurring non-bitumen. A Bayesian isotopic mixing model was used to determine the relative proportions of these three sources in groundwater at both study sites. Although background levels of OSPW-derived AEOs were generally low, one sample containing 49-99% (95% credibility interval) OSPW-derived AEOs was detected within an inferred preferential flow-path, highlighting the potential for this technique to track tailings pond seepage.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Teorema de Bayes , Ácidos Carboxílicos , Campos de Petróleo e Gás , Tanques , Areia
11.
Water Res ; 169: 115243, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31704461

RESUMO

Algal and bacterial communities play a major role in the treatment performance and efficiency of waste stabilisation ponds (WSPs); however, the study of these WSP microbial communities has been challenging. Flow cytometry (FCM) has been used widely as a rapid, culture-independent method of characterising algae and/or bacteria in a range of freshwater and marine environments, and in conventional wastewater treatment processes, but its application to WSP wastewater has been underexplored. In this study, a method for the characterisation of both algal and bacterial microbial populations in WSP wastewater is presented and standardised, using cultures and field samples. We show that SYTO 16 dye is more effective than SYBR Green I for the concurrent detection of both algae and bacteria in samples. Through gating and phenotypic diversity analysis, the FCM results show both spatial and temporal shifts in pond microbial communities. The ability to rapidly determine the spatiotemporal shifts in pond populations is not only important for the improvement of pond operation and monitoring strategies, but also for the planning and management. Flow cytometry has the potential to become a diagnostic tool for ponds to assess treatment performance and determine the most optimal operating conditions.


Assuntos
Microbiota , Tanques , Citometria de Fluxo , Eliminação de Resíduos Líquidos , Águas Residuárias
12.
Int J Syst Evol Microbiol ; 70(1): 576-581, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31613746

RESUMO

Strain F3212T, Gram-stain-negative, aerobic, helical and motile bacterium, was isolated from the marine sediment collected in a sea cucumber culture pond located in Rongcheng, China. Strain F3212T grew optimally at pH 8.5, at 30 °C and in the presence of 3.0 % (w/v) NaCl. Phylogenetic analysis, based on 16S rRNA gene sequences, indicated that strain F3212T belongs to the genus Marinospirillum, clustering with M. celere, M. alkaliphilum, M. minutulum, M. megaterium and M. insulare (with 96.4, 94.6, 93.1, 92.4 and 92.1 % 16S rRNA gene sequence similarities, respectively). The chemotaxonomic properties of strain F3212T were similar to those of members of the genus Marinospirillum. Q-8 was the sole respiratory ubiquinone and the genomic DNA G+C content was 53.3 mol%. The major fatty acids were C18 : 1 ω9c, C16 : 0 and C18 : 0. The polar lipid pattern consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentifed lipid and an unidentified aminophospholipid. The average nucleotide identity scores for strains M. celere DSM 18438T and M. minutulum DSM 6287T were 74.5 and 69.4 %, respectively. The DNA-DNA homologies with M. celere DSM 18438T and M. minutulum DSM 6287T were less than 20 %. It's concluded that strain F3212T represents a new species of the genus Marinospirillum, for which the name Marinospirillum perlucidum sp. nov. is proposed. The type strain is F3212T (=KCTC 52892T=MCCC 1H00198T).


Assuntos
Sedimentos Geológicos/microbiologia , Oceanospirillaceae/classificação , Filogenia , Tanques/microbiologia , Pepinos-do-Mar/microbiologia , Animais , Aquicultura , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Oceanospirillaceae/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA , Ubiquinona/química
13.
Int J Syst Evol Microbiol ; 70(1): 358-363, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31622236

RESUMO

Two Gram-stain-negative, moderately halophilic bacteria, designated strains ECH52T and KHM46, were isolated from the sediment of a grey saltern located in Sinui island at Shinan, Korea. The isolates were aerobic, non-motile, short rods and grew at 15-45 °C (optimum, 37 °C), at pH 6.0-10.0 (optimum, pH 8.0) and with 3-25 % (w/v) NaCl (optimum, 10 % NaCl). Phylogenetic analyses based on 16S rRNA gene sequences indicated that strains ECH52T and KHM46 belonged to the genus Aliifodinibius in the family Balneolaceae with sequence similarities of 94.3-98.6 % and showed the highest sequence similarity to Aliifodinibius halophilus 2W32T (98.6 %), A. sediminis YIM J21T (94.7%), A. salicampi KHM44T (94.6 %) and A. roseus YIM D15T (94.3 %). The DNA G+C content of the genomic DNA of strain ECH52T was 40.8 mol%. The predominant isoprenoid quinone was menaquinone-7 (MK-7) and the major cellular fatty acids were iso-C17 : 1ω9c, iso-C15 : 0, and C16 : 1ω7c and/or iso-C15 : 0 2-OH. The major polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, two unidentified glycolipids and four unidentified lipids. Based on the phylogenetic, phenotypic and chemotaxonomic data, strains ECH52T and KHM46 are considered to represent a novel species of the genus Aliifodinibius , for which the name Aliifodinibius saliphilus sp. nov. is proposed. The type strain is ECH52T (=KACC 19126T=NBRC 112664T).


Assuntos
Bacteroides/classificação , Chlorobi/classificação , Filogenia , Tanques/microbiologia , Salinidade , Técnicas de Tipagem Bacteriana , Bacteroides/isolamento & purificação , Composição de Bases , Chlorobi/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química , Microbiologia da Água
14.
Sci Total Environ ; 704: 135259, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31780174

RESUMO

The industrialization of integrated algae-aquaculture systems entails appropriate information regarding environmental and economic assessments, field and laboratory analyses, and feasibility studies. Accordingly, Scenedesmus obliquus was cultivated in a raceway pond (300 m3), and the algal biomass was used as a protein source for the growth of Nile tilapia (Oreochromis niloticus). Nile tilapia fish was cultivated in five commercial-scale tanks for 44 weeks, having a productivity of 15-20 kg (live weight)·m-3. Among various algal-based fish meals, the diet containing 7.5% microalgae provided the largest body length (29 cm) and weight (402 g), as well as the optimum growth performance parameters. Scenedesmus obliquus was subjected to lipid extraction, and the defatted biomass was also used as a substitute for fishmeal in diets. Nile tilapia grown using the lipid-extracted algae had improved health status, and the biochemical composition was satisfactory. Further, two scenarios were economically investigated: Case 1, the direct use of algal biomass for fish production, and Case 2, the utilization of algae for biodiesel production followed by the application of residual biomass in fishmeal diets. Based on field experiments and financial information reported in the literature, the two options would offset their initial investment cost within payback periods of 7.5 and 6.8 yr, respectively.


Assuntos
Aquicultura , Biocombustíveis , Microalgas , Animais , Biomassa , Ciclídeos , Dieta , Estudos de Viabilidade , Lipídeos , Tanques , Alimentos Marinhos
15.
Eur J Protistol ; 72: 125646, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31785489

RESUMO

A new urostylid ciliate, Anteholosticha songi nov. spec., isolated from forest soil in Tibet, and an American population of Holosticha pullaster (Müller, 1773) Foissner et al., 1991, isolated from a freshwater pond in the USA, are investigated in terms of their morphology, ontogenesis, and molecular biology. Anteholosticha songi nov. spec. is characterized by a slender to ellipsoidal body measuring 160-205 × 40-55 µm in vivo; rod-shaped yellowish cortical granules arranged in irregular short rows; four dorsal kineties; adoral zone consisting of 35-40 membranelles; three frontal, one buccal, one parabuccal, two frontoterminal, two pretransverse, and four to six transverse cirri and 14-25 midventral pairs; 12-22 ellipsoidal macronuclear nodules longitudinally arranged in pairs left of cell mid-line. Supplemental information on morphogenesis in Holosticha pullaster is also presented. The phylogenetic relationship of Anteholosticha and Holosticha inferred from SSU rDNA sequence data are concordant with previous studies and showing that Holosticha is monophyletic whereas Anteholosticha is polyphyletic and should be split into two or more genera.


Assuntos
Hypotrichida/classificação , Filogenia , Hypotrichida/citologia , Hypotrichida/genética , Tanques/parasitologia , RNA Ribossômico 18S/genética , Especificidade da Espécie , Estados Unidos
16.
Sci Total Environ ; 699: 134372, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31683220

RESUMO

This study compared plant growth, nutrient partitioning and total nutrient uptake by tall sedge (Carex appressa) plants in large-scale Constructed Floating Wetlands (CFWs). Two CFWs with a total area of 2088 m2 were installed in a 2.6 ha man-made urban lake to treat stormwater runoff during the construction phase of a 45-ha residential development. After 12 months of operation, parts of the CFWs, with a total area of 147 m2, were removed from the urban lake and relocated into a well-established 0.127-ha stormwater retention pond at another site. Biomass and nutrient concentrations of C. appressa shoots above the floating mat and roots below the mat were analysed at both sites 12, 16 and 25 months after initial planting. Plants at the urban lake maintained an extensive root network but there was no increase in total plant biomass at 16 and 25 months after planting. In contrast, the relocated plants in the stormwater pond showed extensive shoot growth but a significant decline in root biomass. C. appressa at the urban lake removed and sequestered 1.00 ±â€¯1.04 g m-2 N, 0.11 ±â€¯0.07 g m-2 P and 1.03 ±â€¯0.81 g m-2 K while plants at the pond removed 11.20 ±â€¯2.29 g m-2 N, 1.37 ±â€¯0.26 g m-2 P and 16.13 ±â€¯2.88 g m-2 K during 12 and 25 months after planting. This study demonstrated that C. appressa adapted rapidly to changes in nutrient availability. The implications are interesting as nutrient levels can be low in constructed lakes during the initial phase of urban developments but can increase rapidly as the development progresses. The study demonstrated multiple benefits of CFWs for stormwater treatment during the early construction stages of an urban development and the potential benefits of relocating and establishing CFWs in existing stormwater retention ponds and lakes.


Assuntos
Eliminação de Resíduos Líquidos , Áreas Alagadas , Biomassa , Carex (Planta) , Nitrogênio , Fósforo , Plantas , Tanques , Chuva , Poluentes Químicos da Água , Purificação da Água
17.
J Environ Manage ; 254: 109832, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31733480

RESUMO

The chemical evolution of brines resulting from an inactive phosphogypsum pond derived of fertilizer industry located in Huelva (Spain, SW Europe) has been studied based on a weekly sampling from 2014 to 2017. Long-range time variation of metals and ions concentrations in brines are expected to depend on environmental parameters such as rainfall and evaporation. The results show that brines are enriched in F- (1.7-2.0 g/l), Cl- (13-24 g/l), SO42- (7.2-9.3 g/l), V (70-128 mg/l) and U (55-98 mg/l). A great variation of chemical concentrations has been found, due to dilution, recharge and evaporation processes. Most of the elements show peak concentrations in summer, coinciding with the lowest pH values (<1), high conductivity (>133 mS/cm), and high evaporation rates as expected. Nonetheless, F- shows an opposite behaviour, varying its concentrations between 0.9 g/l in summer and 3.7 g/l in the rainy season. According to the results, a future restoration plan for PG ponds should include the removal of brines and layered salts during summer in order to avoid the annual generation of brines and their impact on the environment.


Assuntos
Tanques , Poluentes Químicos da Água , Sulfato de Cálcio , Europa (Continente) , Fósforo , Sais , Espanha
18.
Gen Comp Endocrinol ; 285: 113271, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525378

RESUMO

Neuropeptides have been successfully documented in numerous arthropod species via in silico prediction from transcriptomic and genomic data. We recently sequenced the genome and nine transcriptomes of a chelicerate species, the pond wolf spider, Pardosa pseudoannulata. Here 43 neuropeptide families encoded by 87 neuropeptide genes were identified, among which 84 genes were presented with complete open reading frames. The neuropeptide genes often had paralogs and paralogous genes showed different expression profiles in nine transcriptomes. Six crustacean hyperglycemic hormone/ion transport peptide-like (CHH/ITP) genes were predicted and CHH/ITP6 was expressed much higher than the others. Orcokinin 1 and orcokinin 2 genes were both expressed in brain at a similar level. But, interestingly, orcokinin 1 gene was ubiquitously expressed in appendages while orcokinin 2 gene was enriched in venom gland to an extreme extent. The expression profiling of neuropeptide genes offers clues for further functional investigation. Paralogous genes were also found to be clustered at scaffolds such as nine insulin-like peptide genes at three scaffolds and six pyrokinin genes at two scaffolds, indicating a result of local gene duplication. In contrast, the four C-type allatostatin family members were scattered at five scaffolds, different from their closely associated locations reported in many arthropod species including several spiders. The comprehensive inventory of P. pseudoannulata neuropeptides here expands our repository of chelicerate neuropeptides and further promotes our understanding of neuropeptide evolution and functions.


Assuntos
Simulação por Computador , Neuropeptídeos/metabolismo , Tanques , Proteoma/metabolismo , Aranhas/metabolismo , Sequência de Aminoácidos , Animais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Neuropeptídeos/química , Neuropeptídeos/genética , Aranhas/genética , Transcriptoma
19.
J Environ Radioact ; 211: 106080, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677432

RESUMO

During the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011 significant amounts of radiocaesium were released into the atmosphere from the reactor units 1, 2 and 3. This caused a non-uniform deposition, in composition and direction, of 134Cs and 137Cs in the near field (<30 km) from the reactors. In this work, we elucidate the influence of speciation, including radioactive particles, on mobility and potential bioavailability of radiocaesium in soils and sediments from sites located in different directions and distances from the FDNPP. Samples collected in September 2016 were characterized and subjected to sequential chemical extractions and simulated gastrointestinal fluid leaching, and the 137Cs and 134Cs activities were determined in bulk, grain-size and extracted fractions. The results show that radiocaesium was mainly irreversibly bound and in an inert form. Combined, the two forms contained >90% of the activity present in soils and ~84% in sediments. Digital autoradiography revealed that the inert fraction was predominantly associated with heterogeneities, an indication of radioactive particles. The frequency of heterogeneities was correlated with 137Cs activity concentrations, and both were in agreement with the ambient equivalent air doses measured in situ during sampling. Moreover, in situ gamma spectrometry measurements were used in the InSiCal software tool to derive 134Cs and 137Cs surface contamination. Soil activity concentrations and contamination density estimations, decay-corrected to the day of the FDNPP accident, resulted in 134Cs/137Cs ratios that match the reported release and deposition plumes from the reactor units. Overall, these results demonstrate the persistence of the particle contamination in the Fukushima near field and highlight the importance of including radioactive particles in environmental impact assessments.


Assuntos
Acidente Nuclear de Fukushima , Solo , Disponibilidade Biológica , Radioisótopos de Césio , Japão , Tanques , Monitoramento de Radiação , Poluentes Radioativos do Solo
20.
Environ Sci Pollut Res Int ; 27(6): 6228-6238, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31863385

RESUMO

Fishponds are man-made shallow water bodies that are still little studied because of their small size. They represent high value ecosystems, both environmentally (biodiversity hotspot) and economically (fish production). They can have a high place on the hydrographic network, so their influence on water quality is of first importance for rivers and water bodies located downstream and monitored under the Water Framework Directive. These small water bodies can be a source of contaminants during draining period or an efficient buffer for pesticides. We wanted to evaluate whether these ponds could also be a remediation tool against metals by following the annual evolution of upstream/downstream flows. Cadmium, copper, lead and zinc concentrations were quantified in the dissolved phase upstream and downstream of three ponds, each one having a specific agricultural environment (traditional or organic). Metal concentration was quantified in sediments and water. For the dissolved phase, the predictive non-effect concentration was often exceeded, suggesting an environmental risk. Results highlighted also greater quantity of metals at the downstream of the pond compared to the upstream, suggesting remobilization into the ponds or direct cross-sectional contributions from the watershed (e.g. runoff from crops) or even remobilization. Regarding sediments, minimal contamination was shown but a high mineralogical variability. No buffer effect of ponds, which could reduce the risk of acute or chronic toxicity, was detected.


Assuntos
Monitoramento Ambiental , Metais/análise , Poluentes Químicos da Água/análise , Animais , Estudos Transversais , Ecossistema , Sedimentos Geológicos , Tanques , Rios/química
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