RESUMO
Removing lampenflora, phototrophic organisms developing on rock surfaces in tourist cavities due to the artificial lighting, is a challenge for sustainable and appropriate long-term management of caves. Photosynthetic-based biofilms usually cause rock biodeterioration and an ecological imbalance in cave ecosystems. In this work, a detailed investigation of the effects of the 3 most commonly used lampenflora cleaning operations (NaClO, H2O2 and UVC) was carried out in Pertosa-Auletta Cave (Italy). The application of NaClO showed good disinfection capability over extended periods of time without causing any appreciable rock deterioration. The H2O2 treatment showed to be corrosive for the rock surfaces covered with vermiculation deposits. The chemical alteration of organic and inorganic compounds by H2O2 did not remove biomass, favoring biofilm recovery after three months of treatment. Both NaClO and H2O2 treatments were effective at removing photoautotrophs, although the bacterial phyla Proteobacteria and Bacteroidetes as well as Apicomplexa and Cercozoa among the Eukaryotes, were found to be resistant to these treatments. The UVC treatments did not show any noticeable effect on the biofilms.
Assuntos
Ecossistema , Peróxido de Hidrogênio , Biofilmes , Bactérias , FotossínteseRESUMO
In cave ecosystems tourists represent moving sources of discontinuous disturbances, able to induce transient system responses whose knowledge is crucial in defining appropriate conservation measures. Here we propose an approach to evaluate the amplitude and scales of cave alterations based on high-resolution air monitoring, through the use of purposely developed low-cost monitoring stations and a consistent analytical framework for information retrieval based on time series analysis. In particular, monitoring stations adopt a modular structure based on physical computing platforms acquiring data through several sensors, with means of preventing humidity damages and guaranteeing their continuous operation. Data are then analyzed using wavelet periodograms and cross-periodograms to extract the scales of tourism-induced alterations. The approach has been exemplified in the Pertosa-Auletta Cave, one of the most important underground environments in Southern Italy, highlighting the development of monitoring stations and the information obtainable with the proposed analytical workflow. Here, 2 monitoring stations acquiring data for 1 year at 1' sampling time on temperature, relative humidity, CO2, VOCs, and particulate matter were deployed in trails subjected to different levels of tourism. In terms of Pertosa-Auletta Cave air dynamics, the approach allowed estimating the temporal and spatial scales of tourism-induced alterations in the order of minutes and meters, respectively, with parameter-dependent variations. On more general terms, the approach proved reliable and effective, with its modularity and low-cost fostering its straightforward adoption in other underground ecosystems, where it can support the development of tailored management strategies.
Assuntos
Ecossistema , Monitoramento Ambiental , Cavernas , Material Particulado/análise , TemperaturaRESUMO
The microbiota associated with vermiculations from karst caves is largely unknown. Vermiculations are enigmatic deposits forming worm-like patterns on cave walls all over the world. They represent a precious focus for geomicrobiological studies aimed at exploring both the microbial life of these ecosystems and the vermiculation genesis. This study comprises the first approach on the microbial communities thriving in Pertosa-Auletta Cave (southern Italy) vermiculations by next-generation sequencing. The most abundant phylum in vermiculations was Proteobacteria, followed by Acidobacteria > Actinobacteria > Nitrospirae > Firmicutes > Planctomycetes > Chloroflexi > Gemmatimonadetes > Bacteroidetes > Latescibacteria. Numerous less-represented taxonomic groups (< 1%), as well as unclassified ones, were also detected. From an ecological point of view, all the groups co-participate in the biogeochemical cycles in these underground environments, mediating oxidation-reduction reactions, promoting host rock dissolution and secondary mineral precipitation, and enriching the matrix in organic matter. Confocal laser scanning microscopy and field emission scanning electron microscopy brought evidence of a strong interaction between the biotic community and the abiotic matrix, supporting the role of microbial communities in the formation process of vermiculations.
Assuntos
Cavernas , Microbiota , Acidobacteria , Bactérias/genética , ProteobactériasRESUMO
Microbial degradation is the main responsible for polycyclic aromatic hydrocarbons (PAHs) removal from contaminated soils, and the understanding of this process is pivotal to define effective bioremediation approaches. To evaluate the contribution of several microbial groups in soil anthracene and benzo[a]pyrene degradation, the analysis of phospholipid fatty acid (PLFA) profiles and machine learning techniques were employed. To this end, PLFAs and PAH concentrations were analysed, along 274 days of incubation in mesocosms, in soils artificially contaminated with anthracene and benzo[a]pyrene, subjected to different treatments: untreated soil and soils treated with biowaste compost or fungal consortium. Random forest models, figuring anthracene or benzo[a]pyrene concentrations as dependent variables and PLFAs as predictors, were then built to evaluate the contribution of each variable in PAH degradation. PLFA profiles varied substantially among soil treatments and along time, with the increase of Actinomycetes in soils added with fungi and other Gram+ bacteria in compost amended soils. The former, together with fungi, are primarily responsible for anthracene and benzo[a]pyrene degradation in both treated soils, a process in which also metanotrophs and other Gram+ and Gram- bacteria participate. In untreated soil, the cooperation of a multitude of different microorganisms was, instead, responsible for PAH removal, a process with lower efficiency in respect to treated soils.
Assuntos
Compostagem , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Biodegradação Ambiental , Fungos , Solo , Microbiologia do SoloRESUMO
Antibiotics are emerging pollutants released into the environment through wastewater and manure or effluents from livestock plants. Compared to the wide literature on the effects of antibiotics on the development of drug-resistant bacteria and on the adverse effects on animals and human beings, the effects on plants are less investigated. Here we evaluated the effects of four antibiotics (cloramphenicol: CAP, spiramycin: SPR, spectinomycin: SPT, vancomycin: VAN) belonging to different chemical groups, on seed germination and root development of tomato (Solanum lycopersicum L. cv. San Marzano). Specifically, seed germination and root elongation kinetics, as well as the number of mithotic figures in root apical meristem, were studied in relation to different concentrations of each antibiotic (0, 0.1, 1, 10, 100, 1000mgL-1) for 10 and 7 days, respectively. Results showed that seed germination was not affected, but root development (root elongation kinetics and cell division) was impaired at concentrations from 10mgL-1 (SPT) and 100mgL-1 (CAP) to 1000mgL-1 (SPR and VAN).
Assuntos
Antibacterianos/toxicidade , Poluentes Ambientais/toxicidade , Germinação/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Sementes/efeitos dos fármacos , Solanum lycopersicum/efeitos dos fármacos , Relação Dose-Resposta a Droga , Solanum lycopersicum/crescimento & desenvolvimento , Meristema/efeitos dos fármacos , Meristema/crescimento & desenvolvimento , Modelos Teóricos , Raízes de Plantas/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimentoRESUMO
The Sarno River is considered the most polluted river in Europe and one of the ten most polluted rivers in the world. So far, its quality has been usually evaluated by water and sediment analyses of either inorganic or organic pollutants. However, a biomonitoring approach would be of paramount importance in the evaluation of river quality, since it integrates pollutant temporal fluctuations, as in the case of discontinuous inputs from urban, industrial and agricultural activities. To this end, a passive biomonitoring study of the Sarno River was carried out, using two native aquatic plants accumulators of inorganic pollutants. The spring area was monitored analysing the roots of the semi-submerged Apium nodiflorum, whereas the whole river course was monitored analysing the shoots of the submerged Potamogeton pectinatus. The information on the four macronutrient (Ca, K, Mg, P), the six micronutrient (Cu, Fe, Mn, Na, Ni, Zn) and the four toxic element (Cd, Cr, Pb, V) concentrations were separately combined in the Nemerow Pollution Index. Results evidenced a severe pollution degree of the Sarno River, attributable to toxic elements > micronutrients > macronutrients. In particular, the spring area showed high K concentrations, as well as high concentrations of several micronutrients and toxic elements. A generalized Zn contamination and a progressive macronutrient (above all Ca and P), micronutrient (above all Ni, Cu and Fe) and toxic element (above all Cr and Pb) accumulation toward the mouth was related to pollution from agricultural and urban activities. Industrial sources, especially tanneries along the Solofrana tributary, accounted for high Mn concentrations, whereas the volcanic origin of the substrate accounted for a generalized V contamination.
Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Rios/química , Apiaceae/efeitos dos fármacos , Fenômenos Químicos , Europa (Continente) , Metais Pesados/análise , Potamogetonaceae/efeitos dos fármacos , Estações do Ano , Oligoelementos/análise , Poluentes Químicos da Água/análiseRESUMO
Leafy vegetables have a relatively high potential for Cd uptake and translocation, and are thus considered Cd accumulators. For this reason, leaves and roots of lettuce (Lactuca sativa L.) and endive (Cichorium endivia L.) plants, grown on different agricultural soils in Campania region (southern Italy), subjected to different fertilisation treatments (unfertilisation, compost amendment and mineral fertilisation), were analysed for Cd concentrations. Moreover, to clarify if the highest concentrations found are linked to older and inedible or to younger and edible leaves, external and internal endive leaves were separately analysed. All the leafy vegetables analysed showed on average 2-fold higher Cd concentrations in leaves than in roots. Leaf Cd concentrations in both lettuce and endive plants significantly differed among fertilisation treatments, with values highest in the plants grown on mineral fertilised soils. Apart from the soil fertilisation treatments, however, Cd leaf concentrations were often higher (up to 4-fold) than the threshold deduced by the EU 420/2011 Regulation, although the plants grew on unpolluted soils. Anyway, external leaves of endive plants showed significantly higher concentrations than internal leaves (in some cases the values were 3-fold higher), partly reassuring on the consumption of the younger leaves. Moreover, this study points out two major drawbacks in the Italian and European regulatory frameworks: (1) metal concentration (as total and/or available fraction) limits in agricultural soils are lacking; (2) metal concentration thresholds (currently existing only for Cd and Pb in crops) reported in the EU 420/2011 Regulation, expressed on the fresh weight basis rather than on the dry weight basis, appear not suitable.
Assuntos
Cádmio/análise , Folhas de Planta/química , Poluentes do Solo/análise , Cádmio/toxicidade , Produtos Agrícolas/química , Fertilizantes/análise , Itália , Lactuca/química , Raízes de Plantas/química , Solo/química , Verduras/químicaRESUMO
BACKGROUND: Tomato (Solanum lycopersicum L.) is one of the most important crops in the world and represents a key crop in southern Italy. With the aim to evaluate the nutritional characteristics of tomato fruits in relation to NPK and compost fertilisation, the concentrations of the main nutrients, toxic elements, primary metabolites and total phenols were determined in two varieties (Lido and San Marzano). Each variety was cultivated in a different experimental field, subjected to different agronomic techniques. RESULTS: Concentrations of toxic elements (Cd and Pb) were below the limits indicated by the EU Regulation (2011) in all the fruits analysed. Moreover, fruits obtained from San Marzano plants grown on organic amended soils showed a better overall quality than those obtained on mineral fertilised soil, being characterised by lower N (attributed to lower nitrate and nitrite concentrations), lower Cd, and higher soluble sugar concentrations. Higher concentrations of soluble sugars in fruits from organic amended soils were also observed in the Lido variety. CONCLUSIONS: The agricultural use of quality compost represents an effective strategy to obtain high quality products in an economically and environmentally sustainable way. © 2016 Society of Chemical Industry.
Assuntos
Fertilizantes , Qualidade dos Alimentos , Solo , Solanum lycopersicum/crescimento & desenvolvimento , Humanos , ItáliaRESUMO
BACKGROUND: The populations of Soldanella (Primulaceae) of the southern Apennines (Italy) are unique within the genus for their distribution and ecology. Their highly fragmented distribution range, with three main metapopulations on some of the highest mountains (Gelbison, Sila and Aspromonte massifs) of the area, poses intriguing questions about their evolutionary history and biogeography, and about the possibility of local endemisms. AIMS AND METHODS: In order to clarify the phylogeny and biogeography of the three metapopulations of Soldanella in the southern Apennines, attributed to S. calabrella to date, and to identify possible local endemisms, a comparative approach based on the study of molecular, morphological and ecological characteristics of the populations was employed. Specifically, one nuclear (total ITS) and two plastid (rbcL and trnL) markers were used for the phylogenetic analyses, performed through both maximum likelihood and Bayesian techniques. Among the morphological features, the glandular hair and leaf biometric traits were analysed, and the environment in which the populations grew was characterised for altitude, forest canopy composition and soil pH, C, N and organic matter. RESULTS AND CONCLUSIONS: Our findings demonstrate that the lineage of Soldanella of southern Italy diverged from the Carpathians lineage during the Middle Pleistocene, and underwent an evolutionary radiation during the Late Pleistocene. The populations of the Sila and Aspromonte massifs diverged from the populations of the Gelbison massif around 380000 years ago and are probably undergoing a progressive differentiation due to their isolation. The populations on the Gelbison massif, moreover, have different morphological features from those of the Sila and Aspromonte massifs and a different ecological niche. The molecular, morphological and ecological data clearly demonstrate that the metapopulation of Soldanella on the Gelbison massif belongs to a new taxonomic unit at the species level, which we name Soldanella sacra A. & L. Bellino from the name of the massif on which it was discovered, the "Holy Mountain".
Assuntos
Primulaceae/classificação , Primulaceae/genética , Teorema de Bayes , Evolução Biológica , DNA de Plantas/genética , Ecologia , Itália , Filogenia , Plastídeos/genéticaRESUMO
A vegetation analysis was carried out on a degraded agricultural soil of the Mediterranean area (Campania region, southern Italy) in order to study the effects of different fertilization practices (quality compost, mineral fertilizers, mixed fertilization, and no fertilization) on the whole spontaneous vegetation community. The study was performed for two consecutive years at three different scales (species level, community structure, and community properties), using three different units of abundance (number of individuals, biomass, and cover of each species). The observations were carried out in spring, after 5 and 6 years of soil treatments, on a total area of 4 m(2) for each soil treatment and in each year. The different fertilization practices did not determine changes in species composition; however, the relative abundance of dominant species increased in compost and mixed fertilized soils, particularly in the second year of observation. Although the dominance and diversity were unaffected by the different fertilization practices, the total biomass and total number of individuals increased in compost-amended soils. These results indicate the effectiveness of soil quality compost amendments to enhance natural revegetation, a key step in the recovery of degraded areas.
Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais/métodos , Fertilizantes , Dispersão Vegetal , Solo/química , Solo/normas , Biomassa , Itália , Região do Mediterrâneo , Dispersão Vegetal/fisiologia , Análise de Componente PrincipalRESUMO
Partially mycoheterotrophic (mixotrophic) plants gain carbon from both photosynthesis and their mycorrhizal fungi. This is considered an ancestral state in the evolution of full mycoheterotrophy, but little is known about this nutrition, and especially about the physiological balance between photosynthesis and fungal C gain. To investigate possible compensation between photosynthesis and mycoheterotrophy in the Mediterranean mixotrophic orchid Limodorum abortivum, fungal colonization was experimentally reduced in situ by fungicide treatment. We measured photosynthetic pigments of leaves, stems, and ovaries, as well as the stable C isotope compositions (a proxy for photosynthetic C gain) of seeds and the sizes of ovaries and seeds. We demonstrate that (1) in natural conditions, photosynthetic pigments are most concentrated in ovaries; (2) pigments and photosynthetic C increase in ovaries when fungal C supply is impaired, buffering C limitations and allowing the same development of ovaries and seeds as in natural conditions; and (3) responses to light of pigment and (13)C contents in ovaries shift from null responses in natural conditions to responses typical of autotrophic plants in treated L. abortivum, demonstrating photoadaptation and enhanced use of light in the latter. L. abortivum thus preferentially feeds on fungi in natural conditions, but employs compensatory photosynthesis to buffer fungal C limitations and allow seed development.
Assuntos
Fenômenos Fisiológicos da Nutrição , Orchidaceae/fisiologia , Evolução Biológica , Isótopos de Carbono/metabolismo , Micorrizas/fisiologia , Orchidaceae/metabolismo , Orchidaceae/microbiologia , Fotossíntese/fisiologia , Pigmentos Biológicos/metabolismo , Estruturas Vegetais/metabolismoRESUMO
Plant biodiversity and intra-population genetic variability have not yet been properly exploited in the framework of phytoremediation and soil reclamation. For this reason, iron and other metal accumulation capacity of two Cu and Zn tolerant poplar clones, namely AL22 (Populus alba L.) and N12 (Populus nigra L.), was investigated in a pot experiment. Cuttings of the two clones were planted in iron rich soil collected from an urban-industrial area. Concentrations of Cd, Cu, Fe, Pb and Zn were analysed in leaves (at different times), as well as in stems and in roots (at the end of the experiment), both in control plants and in plants grown on a soil whose Fe availability was artificially enhanced. Results showed that Cd and Zn were preferentially accumulated in leaves, whereas Cu, Fe and Pb were mainly accumulated in roots. The main differences in metal accumulation between clones were related to Cd (about tenfold higher concentrations in N12) and Cu (higher concentrations in AL22). Once soil Fe availability was enhanced, the uptake and accumulation of all metals declined, with the exception of Fe at the first sampling time in AL22 leaves. The different behaviour of the two poplar clones suggests that a thoughtful choice should be made for their use in relation to soil heavy metal remediation.
Assuntos
Ferro/metabolismo , Metais Pesados/metabolismo , Populus/metabolismo , Poluentes do Solo/metabolismo , Oligoelementos/metabolismo , Biodegradação Ambiental , Humanos , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Populus/genéticaRESUMO
Phytoremediation is a cost-effective and environment friendly in situ technique for the reclamation of heavy metal-polluted soils. The efficacy of this technique, which relies on tolerant plant species, can be improved by the use of chelating agents. A pot experiment was carried out to evaluate the phytoextraction and phytostabilisation capacities of a white poplar (Populus alba L.) clone named AL35 previously selected for its marked tolerance to copper (Cu) and zinc (Zn). Cuttings were grown on agricultural soil highly contaminated with Cu and Zn, in the presence or not (controls) of a chelant mixture (EDTA/EDDS) known to enhance metal bioavailability and, hence, uptake by plant roots, or the not yet investigated synthetic, highly biodegradable polyaspartic acid (PASP). Both chelant treatments improved the phytostabilisation of Cu and Zn in AL35 plants, whilst the phytoextraction capacity was enhanced only in the case of Cu. Considering that the effectiveness of PASP as phytostabilizer was comparable or better than that of EDTA/EDDS, the low cost of its large-scale chemical synthesis and its biodegradability makes it a good candidate for chelant-enhanced metal phytoextraction from soil while avoiding the toxic side-effects previously described for both EDTA and EDDS.
Assuntos
Quelantes/metabolismo , Ácido Edético/metabolismo , Recuperação e Remediação Ambiental/métodos , Etilenodiaminas/metabolismo , Peptídeos/metabolismo , Populus/metabolismo , Poluentes do Solo/metabolismo , Succinatos/metabolismo , Biodegradação Ambiental , Cobre/metabolismo , Populus/genética , Zinco/metabolismoRESUMO
We determined genetic variation and metal and polycyclic aromatic hydrocarbon concentrations in Leptodon smithii moss collected in holm oak stands at cities, outskirts and remote areas of Campania and Tuscany (Italy) to investigate if anthropogenic pressure (pollutant emissions and land use change) affects moss genetic richness. In both regions, metal and polycyclic aromatic hydrocarbon concentrations reflected the trend urban>outskirts>remote areas, excepting Tuscany remote site. In both regions, the moss gene diversity increased from urban to remote areas. The findings suggest the extent and the fragmentation of urban green areas, as drivers of moss genetic richness.
Assuntos
Poluentes Atmosféricos/efeitos adversos , Briófitas/efeitos dos fármacos , Briófitas/genética , Cidades , Variação Genética , Itália , QuercusRESUMO
Permanent artificial lighting systems in tourist underground environments promote the proliferation of photoautotrophic biofilms, commonly referred to as lampenflora, on damp rock and sediment surfaces. These green-colored biofilms play a key role in the alteration of native community biodiversity and the irreversible deterioration of colonized substrates. Comprehensive chemical or physical treatments to sustainably remove and control lampenflora are still lacking. This study employs an integrated approach to explore the biodiversity, eco-physiology and molecular composition of lampenflora from the Pertosa-Auletta Cave, in Italy. Reflectance analysis showed that photoautotrophic biofilms are able to absorb the totality of the visible spectrum, reflecting only the near-infrared light. This phenomenon results from the production of secondary pigments and the adaptability of these organisms to different metabolic regimes. The biofilm structure mainly comprises filamentous organisms intertwined with the underlying mineral layer, which promote structural alterations of the rock layer due to the biochemical attack of both prokaryotes (mostly represented by Brasilonema angustatum) and eukaryotes (Ephemerum spinulosum and Pseudostichococcus monallantoides), composing the community. Regardless of the corrosion processes, secondary CaCO3 minerals are also found in the biological matrix, which are probably biologically mediated. These findings provide valuable information for the sustainable control of lampenflora.
Assuntos
Biofilmes , Cavernas , Biofilmes/crescimento & desenvolvimento , Cavernas/microbiologia , Biodiversidade , Itália , Bactérias/classificaçãoRESUMO
Charophytes are amongst the most endangered primary producers in freshwater and coastal ecosystems. In spite of the extensive research on the group and its ecological and conservational relevance, scarce information is available on Mediterranean environments, especially rivers and small water reservoirs, where charophytes face challenging summer droughts and changes in hydrological regimes, as well as pervasive anthropogenic pressures. This research aimed, through repeated field observations, detailed analyses of population traits, and extensive characterization of the colonized environments, to foster an understanding of the distribution, biodiversity, and ecology of charophytes in an area of exceptional environmental value and that is still uninvestigated in relation to its charophyte flora, the southern Campania region (Italy). Overall, 17 populations were discovered, belonging to 4 taxa of the Chara genus: C. globularis, C. gymnophylla, C. vulgaris, and C. vulgaris var. papillata, reduced to 12 populations and to the first 3 taxa by the end of the study. The species occupied different ecological niches and colonized environments such as rivers and small ponds, with environment-dependent morphotypes. The occurrence of few taxa with a wide distribution, often forming ephemeral populations, suggests ongoing constraints on charophyte biodiversity in the area, favoring opportunistic species that are able to benefit from temporary refugia.
RESUMO
Trefoil protein 1 (TFF1) is a small secreted protein belonging to the trefoil factor family of proteins, that are present mainly in the gastrointestinal (GI) tract and play pivotal roles as motogenic factors in epithelial restitution, cell motility, and other incompletely characterized biological processes. We previously reported the up-regulation of TFF1 gene in copper deficient rats and the unexpected property of the peptide to selectively bind copper. Following the previous evidence, here we report the characterization of the copper binding site by fluorescence quenching spectroscopy and mass spectrometric analyses. We demonstrate that Cys58 and at least three Glu surrounding residues surrounding it, are essential to efficiently bind copper. Moreover, copper binding promotes the TFF1 homodimerization, thus increasing its motogenic activity in in vitro wound healing assays. Copper levels could then modulate the TFF1 functions in the GI tract, as well as its postulated role in cancer progression and invasion.
Assuntos
Cobre/metabolismo , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Sítios de Ligação/genética , Linhagem Celular , Movimento Celular , Humanos , Cinética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Multimerização Proteica , Ratos , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fator Trefoil-1 , Proteínas Supressoras de Tumor/genética , CicatrizaçãoRESUMO
Polycyclic aromatic hydrocarbons (PAHs) are hazardous organic compounds with mutagenic, genotoxic and carcinogenic properties. Although PAHs in soil can cause toxicity to microorganisms, the microbial community is able to degrade these compounds. For this reason, it is important to study acute and short-term effects of PAH contamination on soil microbial community, also to shed light on its possible exploitation in soil restoration. The effects of acute PAH contamination on the structure and metabolic activity of microbial communities in three forest (beech, holm oak, black pine) soils were studied. The soils were spiked with phenanthrene, pyrene or benzo[a]pyrene and incubated in experimental mesocosms, under controlled conditions. Enzymatic activities (laccase, total peroxidase and hydrolase), as well as microbial biomass and community structure (through phospholipid fatty acid and ergosterol analyses), were evaluated in the three soil systems 4 days after contamination and compared to no-spiked soils. In soil under holm oak, there was a stimulation of Gram+ bacteria after contamination with all the 3 PAHs, whereas in soil under pine, pyrene and phenanthrene additions mainly stimulated fungi and actinomycetes.
Assuntos
Microbiota , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Biodegradação Ambiental , Florestas , Solo , Microbiologia do SoloRESUMO
In statistics, the identification of environmental criticalities, one of the primary goals of environmental monitoring and management, translates into the detection of spatial outliers. Detected in relation to purposely defined sets of indicators, both global and local outliers are pivotal in the identification not only of the severity and spread of criticalities, but also of their nature and causes. The present research exemplifies a procedural framework to identify environmental criticalities, using two different approaches for the detection of spatial outliers in river ecosystems related to several sets of parameters (organic C, inorganic C, Ca, Co, Cr, Fe, K, Mg, Mn, N, Na, P, S, Si, V, Zn, Cl-, F-, NO3-, SO42-, chlorophyll a, chlorophyll b, pheophytin a, pheophytin b, total carotenoids, pH, and electrical conductivity), including emerging contaminants. To this end, indicator sets diagnostic for specific criticalities, derived from an empirical dataset of water quality parameters, were employed, using detection techniques based on geographically weighted principal component analysis and a modified pairwise Mahalanobis distance-based algorithm. Clear and accurate criticality scenarios were derived, highlighting both the strengths and the limitations of the proposed approach, especially in relation to the classic threshold-based methods.
Assuntos
Rios , Poluentes Químicos da Água/análise , Clorofila A , Ecossistema , Monitoramento Ambiental , Análise Multivariada , Qualidade da ÁguaRESUMO
Copper is an essential element for all living organisms; however, it becomes toxic at high concentrations due to its ability to participate in many redox reactions. This vital micronutrient balance plays an important role in the battle between host and pathogen, due to its use by the host to intoxicate pathogens. In this study, we explore the effects of copper deprivation on Helicobacter infection in mice using the copper chelator tetrathiomolybdate. Our results reveal that Helicobacter infection significantly reduces copper concentration in mice stomachs without affecting its circulating levels. Moreover, in copper-deprived mice, bacteria hardly colonize the epithelium and mice show less gastric damage in comparison with the infected ones. However, when the copper chelator is administered after infection, the condition of the mouse stomachs declines. This could be explained by the lower copper availability in tetrathiomolybdate-treated mice, which would reduce macrophages' action against the pathogen. In this scenario, we observe that the protective factor trefoil factor 1 is induced upon copper-deprived conditions, probably contributing to the inefficacy of infection, whereas, when the chelator is administered after infection, the gene is already silenced by bacteria and cannot be restored. In conclusion, our data suggest that Helicobacter takes advantage of gastric copper reducing its availability for the host and that copper levels have an impact on the outcome of infection.