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1.
Bioresour Technol ; 293: 122057, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31491653

RESUMO

In this study, the effect of culture salinity (4-6% NaCl) on the harvesting of two microalgal strains (i.e., Picochlorum sp., and Tetraselmis sp.) was investigated using pilot-scale TFF membranes. The cultures of these two strains were collected from their respective continuous cultivation in 2, 25,000 L raceway ponds. For both strains, an increase in culture salinity aggravated the membrane fouling and hence negatively influenced the permeate flux rate, biomass concentrating factor, and energy requirement in biomass harvesting. For the TFF membranes, an increase in 1% NaCl salinity, the volume of processed permeate reduced by 30-44 %, the energy consumption per unit volume of permeate increased by 3-63%, and the biomass concentrating factor reduced by 47-61%.


Assuntos
Clorófitas , Microalgas , Biomassa , Tanques , Salinidade
2.
Oecologia ; 191(2): 461-474, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31501978

RESUMO

Climate change has been altering the ocean environment, affecting as a consequence the biological communities including microorganisms. We performed a mesocosm experiment to test whether biodiversity loss caused by one stressor would influence plankton community sensitivity to a subsequent stressor, as envisioned in Vinebrooke's multiple stressor concept. A natural Baltic Sea diatom-dominated phytoplankton assemblage was used as a model system where we examined whether a preceding heat shock would affect the community's response to changing salinity. Initially, the community was treated by a short-term temperature increase of 6 °C, which resulted in a loss of species compared to the control. Thereafter, the control and the heat-shocked communities were subject to a salinity change (- 5 psu, control, + 5 psu). The species Skeletonema dohrnii, Thalassiosira anguste-lineata, Thalassiosira nordenskioeldii, Chaetoceros socialis and Ditylum brightwellii were major components of the control and heat-shocked assemblages (> 80% of the total biomass). We examined the effect on species composition and biodiversity (morphospecies and operational taxonomic units (OTUs) related to phytoplankton) and on phytoplankton biomass. In addition, we explored the single species response of five dominant diatoms on these environmental perturbations. Our results showed that increased salinity significantly reduced the OTUs richness both in the control and the less diverse heated community as well as the phytoplankton biomass in the heated community. On the other hand, decreased salinity significantly increased species richness and phytoplankton biomass in both communities and OTUs richness in the control community. The five dominant diatoms reached their highest biomass under decreased salinity and responded negatively to increased salinity (lower biomass than ambient salinity). Contrary to Vinebrooke's multiple stressor concept, there was no indication that the heat treatment had altered the community's sensitivity to the salinity stress in our study system.


Assuntos
Diatomáceas , Fitoplâncton , Biodiversidade , Resposta ao Choque Térmico , Salinidade
3.
World J Microbiol Biotechnol ; 35(9): 132, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432260

RESUMO

This paper aims to characterize halophilic bacteria inhabiting Algerian Saline Ecosystems (Sebkha and Chott) located in arid and semi-arid ecoclimate zones (Northeastern Algeria). In addition, screening of enzymatic activities, heavy metal tolerance and antagonistic potential against phytopathogenic fungi were tested. A total of 74 bacterial isolates were screened and phylogenetically characterized using 16S rRNA gene sequencing. The results showed a heterogeneous group of microorganisms falling within two major phyla, 52 strains belonging to Firmicutes (70.2%) and 22 strains (30.8%) of γ-Proteobacteria. In terms of main genera present, the isolates were belonging to Bacillus, Halobacillus, Lentibacillus, Oceanobacillus, Paraliobacillus, Planomicrobium, Salicola, Terribacillus, Thalassobacillus, Salibacterium, Salinicoccus, Virgibacillus, Halomonas, Halovibrio, and Idiomarina. Most of the enzymes producers were related to Bacillus, Halobacillus, and Virgibacillus genera and mainly active at 10% of growing salt concentrations. Furthermore, amylase, esterase, gelatinase, and nuclease activities ranked in the first place within the common hydrolytic enzymes. Overall, the isolates showed high minimal inhibitory concentration values (MIC) for Ni2+ and Cu2+ (0.625 to 5 mM) compared to Cd2+ (0.1 to 2 mM) and Zn2+ (0.156 to 2 mM). Moreover, ten isolated strains belonging to Bacillus, Virgibacillus and Halomonas genera, displayed high activity against the pathogenic fungi (Botrytis cinerea, Fusarium oxyporum, F. verticillioides and Phytophthora capsici). This study on halophilic bacteria of unexplored saline niches provides potential sources of biocatalysts and novel bioactive metabolites as well as promising candidates of biocontrol agents and eco-friendly tools for heavy metal bioremediation.


Assuntos
Antibiose , Bactérias/isolamento & purificação , Bactérias/metabolismo , Biota , Microbiologia Ambiental , Salinidade , Argélia , Bactérias/classificação , Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fungos/crescimento & desenvolvimento , Hidrolases/análise , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Testes de Sensibilidade Microbiana , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
4.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2549-2557, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418177

RESUMO

We measured soil water and salt distribution characteristics at 0-40 cm soil depth in a silvopastoral system of Fraxinus chinensis and Robinia pseudoacacia mixed forest × Medicago sativa, which is located in Land Use Scientific Observation Field Base of Ministry of Land and Resource in Wudi, Shandong Province, China. The moving split-window technique was used to analyze the internal-system edge effect. The results showed that both soil water and salt contents in this system heterogeneously distributed in the horizontal direction. The variation of soil water was greater and that of soil salt contents was the smaller when closer to the soil surface. With the mixed forest tree row as the boundary line, the contents of soil water and salt on both sides showed similar change trend. With the decreases of distance to the tree row, soil water content reduced first and then increased but the salt contents had a stable fluctuation at 0-10 cm soil layer. Soil water content showed a trend of decrease-flat-decrease but the salt contents first enhanced and then reduced at 10-20 cm soil layer, respectively. At the deeper soil layer (20-40 cm), the water content fluctuated stably but the salt content continued increasing. Both the contents of soil water and salt in the vertical direction increased significantly with soil depth. Except HCO3- and K+, there was a similar change trend between ions and total salt content in the soil of silvopastoral system, and the correlation between these ions and total salt content was Na+>Cl->SO42->Mg2+>Ca2+. Based on the technique of moving split-window, the edge effect zone of soil water in the silvopastoral system was 2.5 m from the east side of the tree row to 2 m from the west side. Soil salinity in the silvopastoral system was mainly affected by the tree row within the range of 1.0 m, and by both of the tree row and M. sativa within the range of 1.0-3.0 m.


Assuntos
Ecossistema , Rios , Solo/química , China , Salinidade , Cloreto de Sódio , Água
5.
Int J Syst Evol Microbiol ; 69(10): 3299-3304, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31395107

RESUMO

A halophilic archaeaon, strain LT12T, was isolated from saline soil sampled at the Tarim Basin, PR China. The novel strain stained Gram-negative, cells were rod-shaped, and formed light red-pigmented colonies on agar plate. Strain LT12T grew optimally at 3.1 M NaCl, 0.05 M MgCl2, 37 °C and pH 7.5. The cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 1.4 M. Based on the results of phylogenetic analyses of the 16S rRNA and rpoB' genes, strain LT12T was most closely related to Halostella salina CBA1114T(94.4-95.9  and 93.6 % similarities, respectively). The average nucleotide identity and in silico DNA-DNA hybridization values between strain LT12T and H. salina CBA1114T were 81.0 and 24.3 %, respectively. The major polar lipids of strain LT12T were phosphatidic acid, phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and three unidentified glycolipids. The DNA G+C content was 67.2 mol % (genome). Based on the phenotypic, chemotaxonomic and phylogenetic properties, strain LT12T represents a novel species of the genus Halostella for which the name Halostellalimicola sp. nov. is proposed. The type strain is LT12T (=CGMCC 1.14941T=JCM 30667T).


Assuntos
Halobacteriaceae/classificação , Filogenia , Salinidade , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Arqueal/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Glicolipídeos/química , Halobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Int J Syst Evol Microbiol ; 69(10): 3305-3309, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31418672

RESUMO

A novel Gram-stain-negative, rod-shaped, beige-coloured, motile, facultatively anaerobic bacterium, designated as E84T, was isolated from sediment sampled from a marine solar saltern in Wendeng, PR China. Phylogenetic analysis based on 16S rRNA gene sequencing showed that Rhodosalinus sediminis WDN1C137T was the closest phylogenetic relationship, with 16S rRNA gene sequence similarity of 96.9 %. Optimal growth occurred at 33-37 °C (range, 20-40 °C), at pH 7.5 (pH 7.0-8.5) and with 6.0 % (w/v) NaCl (0.5-20.0 %). The sole respiratory quinone was Q-10. The major fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C18 : 0 and cyclo C19 : 0ω8c. The polar lipids were phosphatidylglycerol, one unidentified glycolipid, two unidentified phospholipids and two unidentified lipids. The genomic DNA G+C content of strain E84T was 69.8 mol%. Based on the results of physiological, genotypic, phylogenetic and chemotaxonomic analyses, we concluded that strain E84T represents a novel species of the genus Rhodosalinus, for which the name Rhodosalinus halophilus sp. nov. is proposed. The type strain is E84T (=KCTC 52697T=MCCC 1H00231T).


Assuntos
Filogenia , Rhodobacteraceae/classificação , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhodobacteraceae/isolamento & purificação , Salinidade , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
7.
Int J Syst Evol Microbiol ; 69(10): 3056-3061, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31310196

RESUMO

A novel Gram-stain-negative, facultatively anaerobic, oxidase-negative, catalase-positive bacillus, designated WD2A32T, was isolated from a marine solar saltern in the coast of Weihai, Shandong Province, PR China. Strain WD2A32T grew optimally at 37-40 °C (range, 20-45 °C) and pH 7.0-7.5 (range, 6.5-8.0) and was tolerant to 6-8 % (w/v) NaCl (range, 2-12 %). The 16S rDNA of strain WD2A32T was most similar (93.5 %) to that of Rhodovibrio salinarumDSM 9154T (the type species of the genus Rhodovibrio), followed by Limimonas halophilaDSM 25584T (92.4 %; the type species of the genus Limimonas). The similarities to the type strains of the genera Pelagibiusand Limibacilluswere less than 91.0 %. The draft genome sequence of strain WD2A32T contained 72 contigs (>507 bp) of 4 237 996 bp with a DNA G+C content of 65.5 mol%. The major polar lipids of strain WD2A32T were phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and unidentified aminolipids; major cellular fatty acids were summed feature 8 (C18 : 1ω7c/C18 : 1ω6c) and C19 : 0 cyclo ω8c; the major respiratory quinone was Q-10. On the basis of the results from chemotaxonomic, physiological and biochemical analyses, strain WD2A32T represents a novel species of a novel genus in the family Rhodospirillaceae, for which the name Ferruginivarius sediminum gen. nov., sp. nov. has been proposed. The type strain is WD2A32T (=KCTC 52888T=MCCC 1H00201T).


Assuntos
Filogenia , Rhodospirillaceae/classificação , Salinidade , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhodospirillaceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
8.
BMC Plant Biol ; 19(1): 331, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31357955

RESUMO

BACKGROUND: Salt stress is one of the environmental factors that greatly limits crop production worldwide because high salt concentrations in the soil affect morphological responses and physiological and metabolic processes, including root morphology and photosynthetic characteristics. Soil aeration has been reported to accelerate the growth of plants and increase crop yield. The objective of this study was to examine the effects of 3 NaCl salinity levels (28, 74 and 120 mM) and 3 aeration volume levels (2.3, 4.6 and 7.0 L/pot) versus non-aeration and salinity treatments on the root morphology, photosynthetic characteristics and chlorophyll content of potted tomato plants. RESULTS: The results showed that both aeration volume and salinity level affected the root parameters, photosynthetic characteristics and chlorophyll content of potted tomato plants. The total length, surface area and volume of roots increased with the increase in aeration volume under each NaCl stress level. The effect was more marked in the fine roots (especially in ≤1 mm diameter roots). Under each NaCl stress level, the photosynthetic rate and chlorophyll content of tomato significantly increased in response to the aeration treatments. The net photosynthetic rate and chlorophyll a and t content increased by 39.6, 26.9, and 17.9%, respectively, at 7.0 L/pot aeration volume compared with no aeration in the 28 mM NaCl treatment. We also found that aeration could reduce the death rate of potted tomato plants under high salinity stress conditions (120 mM NaCl). CONCLUSIONS: The results suggest that the negative effect of NaCl stress can be offset by soil aeration. Soil aeration can promote root growth and increase the photosynthetic rate and chlorophyll content, thus promoting plant growth and reducing the plant death rate under NaCl stress conditions.


Assuntos
Lycopersicon esculentum/fisiologia , Fotossíntese , Raízes de Plantas/anatomia & histologia , Clorofila/metabolismo , Lycopersicon esculentum/anatomia & histologia , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Raízes de Plantas/fisiologia , Salinidade , Estresse Salino , Solo
9.
Plant Mol Biol ; 101(1-2): 203-220, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31297725

RESUMO

KEY MESSAGE: Here, a functional characterization of a wheat MSR has been presented: this protein makes a contribution to the plant's tolerance of abiotic stress, acting through its catalytic capacity and its modulation of ROS and ABA pathways. The molecular mechanism and function of certain members of the methionine sulfoxide reductase (MSR) gene family have been defined, however, these analyses have not included the wheat equivalents. The wheat MSR gene TaMSRA4.1 is inducible by salinity and drought stress and in this study, we demonstrate that its activity is restricted to the Met-S-SO enantiomer, and its subcellular localization is in the chloroplast. Furthermore, constitutive expression of TaMSRA4.1 enhanced the salinity and drought tolerance of wheat and Arabidopsis thaliana. In these plants constitutively expressing TaMSRA4.1, the accumulation of reactive oxygen species (ROS) was found to be influenced through the modulation of genes encoding proteins involved in ROS signaling, generation and scavenging, while the level of endogenous abscisic acid (ABA), and the sensitivity of stomatal guard cells to exogenous ABA, was increased. A yeast two-hybrid screen, bimolecular fluorescence complementation and co-immunoprecipitation assays demonstrated that heme oxygenase 1 (HO1) interacted with TaMSRA4.1, and that this interaction depended on a TaHO1 C-terminal domain. In plants subjected to salinity or drought stress, TaMSRA4.1 reversed the oxidation of TaHO1, activating ROS and ABA signaling pathways, but not in the absence of HO1. The aforementioned properties advocate TaMSRA4.1 as a candidate for plant genetic enhancement.


Assuntos
Heme Oxigenase-1/metabolismo , Metionina Sulfóxido Redutases/metabolismo , Transdução de Sinais , Estresse Fisiológico , Triticum/enzimologia , Ácido Abscísico/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Arabidopsis/fisiologia , Secas , Perfilação da Expressão Gênica , Heme Oxigenase-1/genética , Metionina Sulfóxido Redutases/genética , Oxirredução , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Salinidade , Tolerância ao Sal , Plântula/enzimologia , Plântula/genética , Plântula/fisiologia , Triticum/genética , Triticum/fisiologia , Técnicas do Sistema de Duplo-Híbrido
10.
Ying Yong Sheng Tai Xue Bao ; 30(6): 2087-2092, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31257783

RESUMO

The scyphozoan genus Aurelia is one of the main contributors causing jellyfish blooms in global coastal waters. The population and reproduction of polyps are important factors to the outbreak of jellyfish. In this study, the effects of different salinity on the survival and asexual reproduction of Aurelia coerulea polyps were explored, which were cultured at the high (21 ℃) and low temperature (12 ℃), respectively. The results showed that more than 90% polyps could survive in the salinity range of 15-40 at the high temperature, with a range of salinity for budding being 20-32 and an optimum value of 28. The polyps were able to produce podocysts to tolerate low (≤15) and high (≥36) salinity conditions. At the low temperature, the survival rates of polyps were more than 90% in the salinity range of 20-40. The polyps could produce more buds in the salinity range of 20-32, with an optimum of 28. The salinity range of 20-40 was suitable for strobilation, with an optimum range of 28-32. It is concluded that the polyps of Aurelia coerulea can tolerate wide salinity variations, and that the salinity in a certain range has no significant influence on the asexual reproduction of polyps.


Assuntos
Salinidade , Cifozoários/fisiologia , Temperatura Ambiente , Animais , Reprodução , Reprodução Assexuada
11.
BMC Plant Biol ; 19(1): 300, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288738

RESUMO

BACKGROUND: Salinity is a major abiotic stress that limits the growth, productivity, and geographical distribution of plants. A comparative proteomics and gene expression analysis was performed to better understand salinity tolerance mechanisms in chickpea. RESULTS: Ten days of NaCl treatments resulted in the differential expression of 364 reproducible spots in seedlings of two contrasting chickpea genotypes, Flip 97-43c (salt tolerant, T1) and Flip 97-196c (salt susceptible, S1). Notably, after 3 days of salinity, 80% of the identified proteins in T1 were upregulated, while only 41% in S2 had higher expression than the controls. The proteins were classified into eight functional categories, and three groups of co-expression profile. The second co-expressed group of proteins had higher and/or stable expression in T1, relative to S2, suggesting coordinated regulation and the importance of some processes involved in salinity acclimation. This group was mainly enriched in proteins associated with photosynthesis (39%; viz. chlorophyll a-b binding protein, oxygen-evolving enhancer protein, ATP synthase, RuBisCO subunits, carbonic anhydrase, and fructose-bisphosphate aldolase), stress responsiveness (21%; viz. heat shock 70 kDa protein, 20 kDa chaperonin, LEA-2 and ascorbate peroxidase), and protein synthesis and degradation (14%; viz. zinc metalloprotease FTSH 2 and elongation factor Tu). Thus, the levels and/or early and late responses in the activation of targeted proteins explained the variation in salinity tolerance between genotypes. Furthermore, T1 recorded more correlations between the targeted transcripts and their corresponding protein expression profiles than S2. CONCLUSIONS: This study provides insight into the proteomic basis of a salt-tolerance mechanism in chickpea, and offers unexpected and poorly understood molecular resources as reliable starting points for further dissection.


Assuntos
Cicer/fisiologia , Proteínas de Plantas/metabolismo , Proteômica , Cicer/genética , Regulação da Expressão Gênica de Plantas , Genótipo , Fotossíntese , Proteínas de Plantas/genética , Salinidade , Tolerância ao Sal , Plântula/genética , Plântula/fisiologia , Estresse Fisiológico
12.
BMC Plant Biol ; 19(1): 297, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286880

RESUMO

BACKGROUND: The modification effect of leaching fraction (LF) on the physiological responses of plants to irrigation water salinity (ECiw) remains unknown. Here, leaf gas exchange, photosynthetic light-response and CO2-response curves, and total carbon (C) and nitrogen (N) accumulation in hot pepper leaves were investigated under three ECiw levels (0.9, 4.7 and 7.0 dS m- 1) and two LFs treatments (0.17 and 0.29). RESULTS: Leaf stomatal conductance was more sensitive to ECiw than the net photosynthesis rate, leading to higher intrinsic water use efficiency (WUE) in higher ECiw, whereas the LF did not affect the intrinsic WUE. Carbon isotope discrimination was inhibited by ECiw, but was not affected by LF. ECiw reduced the carboxylation efficiency, photosynthetic capacity, photorespiration rate, apparent quantum yield of CO2 and irradiance-saturated rate of gross photosynthesis; however, LF did not influence any of these responses. Total C and N accumulation in plants leaves was markedly increased with either decreasing ECiw or increasing LF. CONCLUSIONS: The present study shows that higher ECiw depressed leaf gas exchange, photosynthesis capacity and total C and N accumulation in leaves, but enhanced intrinsic WUE. Somewhat surprisingly, higher LF did not affect the intrinsic WUE but enhanced the total C and N accumulation in leaves.


Assuntos
Irrigação Agrícola , Capsicum/fisiologia , Fotossíntese , Salinidade , Água/metabolismo , Carbono/metabolismo , Nitrogênio/metabolismo , Água/análise
13.
Bioresour Technol ; 289: 121714, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31323719

RESUMO

In this study, multistage contact oxidation reactor (MCOR) with a novel carrier was used for treatment of high-strength sodium saccharin wastewater (SSW) under stepwise increasing salinities from 1.0% to 8.0%. The results revealed that MCOR could effectively remove the organic pollutants from SSW when influent salinity was no more than 4.5%; the chemical oxygen demand (COD) and NH4+-N removal efficiency under the optimal operating parameters ranged up to 91.5% and 92.7%, respectively. Microbial diversity analysis illustrated that the dominant microbes in SSW treatment system were substantially distinct at different salinities. Pseudomonas was predominant at salinity of 3.5%, while Marinobacterium (a species involved in COD removal) was enriched to a greater degree at salinity of 7.0%. CCA suggested that salinity was the main factor for dynamic evolutions of microbial community structures. This work demonstrated that MCOR is an appropriate method for the treatment of high-strength, high-salinity SSW.


Assuntos
Microbiota , Sacarina/metabolismo , Águas Residuárias/química , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos/microbiologia , Oxirredução , Sacarina/análise , Salinidade
14.
Environ Monit Assess ; 191(8): 519, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31359137

RESUMO

One of the most important factors considered in leaching salt-affected soils is reducing the amount of water and leaching time particularly when magnetizing water is used. In this study, soil column experiments were conducted to assess the rate of salt removal and estimate the amount of water required for leaching in order to reduce salinity (EC) to ≤ 4 dS m-1 and sodicity (ESP) to < 10. Soil samples with EC = 216 dS m-1 and ESP = 82 were taken from Basrah City, Iraq, for the conduction of laboratory experiments, and these samples were subjected to magnetized water (MW) with magnetic fields of 1, 3, 5, 7, and 9; different exposure time; and constant flow velocity. Experimental results were compared with the results of control soil columns leached with non-magnetized water (NMW), and the comparison shows that the leaching times for MW with magnetic fields of 9, 7, 5, 3, and 1 were less by 17.3%, 10.8%, 8.9%, 7.6%, and 3.9%, respectively. Also, less amount of MW was required for leaching, but when field magnetic was 9, the amount was increased by 20%. Predicted values of EC and ESP obtained from the proposed equations were found in agreement with experimental results.


Assuntos
Recuperação e Remediação Ambiental/métodos , Campos Magnéticos , Poluentes do Solo/análise , Solo/química , Água/química , Iraque , Modelos Teóricos , Salinidade
15.
Int J Syst Evol Microbiol ; 69(10): 3121-3127, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31339480

RESUMO

A Gram-stain-positive, moderately halophilic bacterium, designated strain BH258T, was isolated from solar saltern sediment sampled at Shinan in the Republic of Korea. Cells of strain BH258T were found to be strictly aerobic, motile, endospore-forming rods which could grow at 15-45 °C (optimum, 35 °C), at pH 5.5-9.0 (pH 7.0) and at salinities of 0.5-20 % (w/v) NaCl (7-10%). Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain BH258T belongs to the genus Aquibacillus, showing highest sequence similarity to Aquibacillus koreensis BH30097T (96.1 %), Aquibacillus albus YIM 93624T (95.9 %), Aquibacillus halophilus B6BT (95.6 %) and Aquibacillus salifodinae WSY08-1T (95.1 %). The predominant isoprenoid quinone was identified as menaquinone-7, and the cell-wall peptidoglycan was found to contain meso-diaminopimelic acid as the diagnostic diamino acid. The major fatty acids were identified as anteiso-C15 : 0, iso-C16 : 0, anteiso-C17 : 0 and iso-C15 : 0. The major polar lipids were identified as phosphatidylglycerol, diphosphatidylglycerol and three unidentified phospholipids. The DNA G+C content of this novel isolate was determined to be 37.35 mol%. On the basis of the results of phylogenetic, phenotypic and chemotaxonomic analyses in this study, strain BH258T is considered to represent a novel species of the genus Aquibacillus, for which the name Aquibacillus sediminis sp. nov. is proposed. The type strain is BH258T (=KACC 18680T=NBRC 111875T).


Assuntos
Bacillaceae/classificação , Filogenia , Salinidade , Microbiologia do Solo , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Sedimentos Geológicos/microbiologia , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
16.
Environ Monit Assess ; 191(8): 492, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300895

RESUMO

Irrigation water salinity is one of the factors that reduces agricultural production. Guilan Province is one of the most important rice-producing areas in Iran where groundwater is used for irrigation. The temporal and spatial variations of groundwater salinity were studied in the coastal strip covering 4285 km2 of the province using data from 73 wells, as well as its estimated effect on the rice yield. Data on mean electrical conductivity (EC) for each 6-month period of 12 consecutive years, from the second half of 2002 until the end of 2014, were analyzed and resulted in 25 mean ECs. EC maps and maps of the probability of higher salinity areas were obtained by using ordinary kriging (OK) and indicator kriging (IK) in ArcGIS 9.3 software, respectively. Thereby, areas belonging to different salinity classes were outlined and places with higher salinity reducing the rice yield were identified. In addition, the Mann-Kendall test and Sen's slope were used to project future changes. The results indicated that due to the salinity of groundwater in the coastal strip area, the minimum and the maximum rice yields were 80% and 100%, respectively. Using the IK method, higher probability of groundwater salinity reducing the yield was found from the central parts toward the east. The Mann-Kendal test result showed significant temporal trends of the size of areas below the 100% yield (EC < 1 dS/m) and 90-100% yield (1 < EC < 1.34 dS/m) thresholds. The equations given by Sen's slope estimator indicated that the groundwater salinity will not be a limiting factor for achieving 100% rice yields from the year of 2021 onward in all of the Guilan coastal area. The trend of increasing precipitation in the area may be an important cause.


Assuntos
Irrigação Agrícola/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Grão Comestível/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Água Subterrânea/química , Oryza/crescimento & desenvolvimento , Irrigação Agrícola/tendências , Previsões , Irã (Geográfico) , Salinidade , Análise Espacial
17.
Environ Monit Assess ; 191(8): 512, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31346834

RESUMO

Mass mortality of fishes was reported at the Adyar estuary, South India, during November 2017. The probable reasons for fish mortality are analyzed in this paper. Critical assessments on water quality parameters including the metal concentrations, nutrients, and histology of gills and liver of fish (Mugil cephalus) isolated from the impact zone were performed. Among the metals observed, chromium showed levels (3.64 ± 0.001 mg L-1) much above the average permissible limits (0.1 mg L-1). The measured values of physico-chemical parameters in the impact zone are as follows: dissolved oxygen 4.7 ± 0.22 mg L-1, total alkalinity 132 ± 4 CaCO3 mg L-1, salinity 5.3 ± 0.3 PSU, temperature 27.8 ± 0.16 °C, nitrate, 1.66 ± 0.48 mg L-1, nitrite 0.01 ± 0.0008 mg L-1, ammonia 0.03 ± 0.001 mg L-1, phosphate 1.52 ± 0.002 mg L-1, and silicate 13.85 ± 3.1 mg L-1. The low salinity could have escalated the toxicity of the metal. In addition, histology of gills and liver showed cellular necrosis, epithelial lifting, hyperplasia, edema, mucous cell proliferation in the gills, cytoplasmic vacuolation of hepatocytes, and degeneration of liver which reveal that chromium toxicity is the most probable cause for mass mortality.


Assuntos
Monitoramento Ambiental , Peixes , Poluentes Químicos da Água/análise , Animais , Estuários , Brânquias/química , Índia , Nitratos , Nitritos , Salinidade , Alimentos Marinhos , Smegmamorpha , Temperatura Ambiente , Qualidade da Água
18.
Chemosphere ; 233: 954-965, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31340423

RESUMO

Heavy metals such as cadmium and zinc constitute major pollutants in coastal areas and frequently accumulate in salt marshes. The wetland halophyte plant species Kosteletzkya pentacarpos is a promising species for phytostabilization of contaminated areas. In order to assess the role of the antisenescing phytohormone cytokinin in heavy metal resistance in this species, seedlings were exposed for two weeks to Cd (10 µM), Zn (100 µM) or Cd + Zn (10 µM + 100 µM) in the presence or absence of 50 mM NaCl and half of the plants were sprayed every two days with the cytokinin trans-zeatine riboside (10 µM). Zinc reduced the endogenous cytokinin concentration. Exogenous cytokinin increased plant growth, stomatal conductance, net photosynthesis and total ascorbate and reduced oxidative stress estimated by malondialdehyde in Zn-treated plants maintained in the absence of NaCl. Heavy metal induced an increase in the senescing hormone ethylene which was reduced by cytokinin treatment. Plants exposed to the mixed treatment (Cd + Zn) exhibited a specific hormonal status in relation to accumulation of abscisic acid and depletion of salicylic acid. Non-protein thiols (glutathione and phytochelatins) accumulated in response to Cd and Cd + Zn. It is concluded that toxic doses of Cd and Zn have different impacts on the plant behavior and that the simultaneous presence of the two elements induces a specific physiological constraint at the plant level. Salinity helps the plant to cope with heavy metal toxicities and the plant hormone cytokinin assumes key function in Zn resistance but its efficiency is lower in the presence of NaCl.


Assuntos
Cádmio/toxicidade , Citocininas/metabolismo , Hibiscus/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Cloreto de Sódio/farmacologia , Zinco/toxicidade , Ácido Abscísico/análise , Glutationa/metabolismo , Hibiscus/crescimento & desenvolvimento , Fotossíntese/efeitos dos fármacos , Fitoquelatinas/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Ácido Salicílico/análise , Salinidade , Plântula/fisiologia , Poluentes Químicos da Água/toxicidade , Áreas Alagadas
19.
Ecotoxicol Environ Saf ; 182: 109347, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31254854

RESUMO

This study was conducted to investigate the effect of industrial solid wastes (ISWs) and salinity on growth and heavy metals uptake by cucumber (Cucumis sativus L.). The soil was treated with 5% and 10% of the ceramic factory (CFW), stone cutting (SCW) and sugar factory (SFW) wastes. Plant of cucumber was grown under greenhouse conditions in control and ISWs treated soils and stressed with electrical conductivities of 0, 4 and 8 dS m-1. Plants were harvested after 2 months and separated into root, shoot, and fruit. Then, dry weights and heavy metals contents in each fraction of plants were determined. The addition of all ISWs in soil increased total heavy metals content in the soil. In all treatments, growth parameters of cucumber decreased when irrigated with saline waters. As compared to control soil, the addition of CFW and SCW to soil decreased plant dry weight, while, it was improved with the addition of the SFW. The result of plant analysis showed that there was an increase in the contents of heavy metals (except Cr) in all parts of cucumber with the addition of ISWs. Salinity decreased the content of Zn uptake and increased another heavy metal uptake by all parts of the plants. The application of ISWs and salinity did not show a significant effect on bioconcentration (BCF) and transfer factor (TF) of heavy metals in plants. The health risk index (HRI) values of all heavy metals for both adults and children were found to be less than 1, so, the health risk of heavy metal for people who consume cucumber grown in these industrial areas was generally assumed to be safe.


Assuntos
Cucumis sativus/metabolismo , Metais Pesados/metabolismo , Estresse Salino , Poluentes do Solo/metabolismo , Resíduos Industriais/análise , Metais Pesados/análise , Salinidade , Solo , Poluentes do Solo/análise , Resíduos Sólidos/análise
20.
Environ Monit Assess ; 191(7): 460, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31236680

RESUMO

Hydrochemical processes have a great influence on the groundwater quality especially in arid regions where groundwater is the single most important source of water supply. The present study was carried out in the Wadi Ad Dawasir region of Saudi Arabia. The objective of this study was to determine the processes influencing the groundwater composition in the region by integrated hydrochemical and statistical assessment. Hydrochemical data from 140 groundwater samples were interpreted using hydrochemical and statistical techniques. Evaporation, mineral dissolution, reverse ion exchange, and chloride/nitrate contamination from irrigation return flows were the main geogenic and anthropogenic sources influencing the groundwater composition. Principal component analysis was carried out to determine the component showing the maximum variability in the data. Two principal components were extracted. The first principal component representing gypsum dissolution and anthropogenic pollution (chloride and nitrate pollution from agricultural farms) was more pronounced in the western part of the study area whereas the second principal component representing silicate weathering process was more dominant in the eastern part. Total dissolved solid was found to be the single most important hydrochemical parameter showing the maximum variation in the analyzed data set. This study demonstrates that the loadings of the individual hydrochemical parameters in the extracted principal component and the component scores of the individual samples for each extracted principal component can be effectively used for determining the hydrochemical processes influencing the groundwater chemistry in an area.


Assuntos
Monitoramento Ambiental/métodos , Água Subterrânea/química , Hidrologia/métodos , Poluentes Químicos da Água/análise , Poluição da Água/análise , Agricultura , Sulfato de Cálcio/análise , Cloretos/análise , Clima Desértico , Troca Iônica , Nitratos/análise , Análise de Componente Principal , Salinidade , Arábia Saudita , Abastecimento de Água , Tempo (Meteorologia)
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