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1.
Cureus ; 15(1): e33864, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36819366

RESUMO

Osteogenesis imperfecta (OI) is a hereditary disease of connective tissue characterized by the loss of bone density and mass, which increases the fragility of the bones, thus presenting multiple fractures throughout the years followed by bone deformity and articular instability. This condition has various clinical presentations. We present four cases of OI, one case with type I, two cases with type II, and one case with type III. The clinical diagnosis in most of the cases was clinical; only one of them was confirmed with genomic sequence. The treatment of these cases was based on medication, orthopedic surgery, and recovery and physical therapy. The evolution was torpid in these cases but with prolonged life expectancy despite the severity and type of OI. It is important to highlight that the patients did not have a neurocognitive compromise. Early diagnosis and multidisciplinary medical management are crucial in obtaining better outcomes for this disease, improving the quality of life, and avoiding complications.

2.
Sci Total Environ ; 857(Pt 1): 159288, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36220464

RESUMO

Mediterranean savannahs (dehesas) are agro-sylvo-pastoral systems with a marked seasonality, with severe summer drought and favourable rainy spring and autumn. These conditions are forecasted to become more extreme due to the ongoing global climate change. Under such conditions, it is key to understand soil organic matter (SOM) dynamics at a molecular level. Here, analytical pyrolysis (Py-GC/MS) combined with chemometric statistical approaches was used for the molecular characterization of SOM in a five-years field manipulative experiment of single and combined rainfall exclusion (drought) and increased temperature (warming). The results indicate that SOM molecular composition in dehesas is mainly determined by the effect of the tree canopy. After only five years of the climatic experiment, the differences caused by the warming, drought and the combination of warming+drought forced climate scenarios became statistically significant with respect to the untreated controls, notably in the open pasture habitat. The climatic treatments mimicking foreseen climate changes affected mainly the lignocellulose dynamics, but also other SOM compounds (alkanes, fatty acids, isoprenoids and nitrogen compounds) pointing to accelerated humification processes and SOM degradation when soils are under warmer and dryer conditions. Therefore, it is expected that, in the short term, the foreseen climate change scenarios will exert changes in the Mediterranean savannah SOM molecular structure and in its dynamic.


Assuntos
Mudança Climática , Solo , Solo/química , Estrutura Molecular , Ecossistema , Compostos Orgânicos
3.
Front Psychol ; 11: 566900, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33101136

RESUMO

CONTEXT: The emergency situation caused by coronavirus disease 2019 (COVID-19) has affected different facets of society. Although much of the attention is focused on the health sector, other sectors such as education have also experienced profound transformations and impacts. This sector is usually highly affected by psychosocial risks, and this could be aggravated during the current health emergency. Psychosocial risks may cause health problems, lack of motivation, and a decrease of effectiveness at work, which in turn affect the quality of teaching. Despite their importance, there are hardly any studies that analyze psychosocial risks of non-university teachers during a health emergency such as that caused by COVID-19. OBJECTIVES: The aim of this study was to analyze the perception of COVID-19 and the psychosocial risks of non-university teachers comparing Spain and Mexico during the state of alarm caused by COVID-19. METHODS: Data were collected from 421 non-university teachers (80.2% women; 56.3% from Mexico, 43.7% from Spain) aged 24-60 (M = 39.32, SD = 10.21) via a self-completed questionnaire during the pandemic from March to April 2020. RESULTS: Data analysis suggests that inequity is the most important risk, followed by work overload. Teachers appear to be moderately satisfied with the information on COVID-19 and the measures taken, while their satisfaction with the available resources is lower. When comparing the two countries, significant differences can be observed in every risk considered except for social support, with lower levels in Mexican teachers compared to Spanish ones. In the case of the perception of COVID-19 and its impact, the perception in general of levels of information, measures, and resources is better among Mexican teachers than among Spanish ones, who present higher scores of the impact of the health emergency. CONCLUSION: The results underline the importance of the professional's perception of resources during a health emergency, which could prevent to some extent burnout and possible alterations associated with it. The measures taken by the responsible entities and the provision of information do affect teachers not only directly but also indirectly by making them more vulnerable to psychosocial risks that could affect their health and professional performance, thus affecting students as well.

4.
Sci Rep ; 10(1): 6434, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32296130

RESUMO

Fungi play a key role in the functioning of soil in terrestrial ecosystems, and in particular in the remediation of degraded soils. The contribution of fungi to carbon and nutrient cycles, along with their capability to mobilise soil trace elements, is well-known. However, the importance of life history strategy for these functions has not yet been thoroughly studied. This study explored the soil-fungi relationship of two wild edible fungi, the ectomycorrhizal Laccaria laccata and the saprotroph Volvopluteus gloiocephalus. Fruiting bodies and surrounding soils in a mine-spill contaminated area were analysed. Isotope analyses revealed Laccaria laccata fruiting bodies were 15N-enriched when compared to Volvopluteus gloiocephalus, likely due to the transfer of 15N-depleted compounds to their host plant. Moreover, Laccaria laccata fruiting bodies δ13C values were closer to host plant values than surrounding soil, while Volvopluteus gloiocephalus matched the δ13C composition to that of the soil. Fungal species presented high bioaccumulation and concentrations of Cd and Cu in their fruiting bodies. Human consumption of these fruiting bodies may represent a toxicological risk due to their elevated Cd concentrations.


Assuntos
Agaricales/química , Isótopos de Carbono/análise , Isótopos de Nitrogênio/análise , Poluentes do Solo/análise , Oligoelementos/análise , Agaricales/metabolismo , Bioacumulação , Cádmio/análise , Cádmio/metabolismo , Cádmio/toxicidade , Isótopos de Carbono/metabolismo , Cobre/análise , Cobre/metabolismo , Cobre/toxicidade , Monitoramento Ambiental , Carpóforos/química , Carpóforos/metabolismo , Humanos , Mineração , Intoxicação Alimentar por Cogumelos/prevenção & controle , Isótopos de Nitrogênio/metabolismo , Solo/química , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Oligoelementos/metabolismo , Oligoelementos/toxicidade
5.
J Environ Manage ; 233: 812-822, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30316582

RESUMO

In recent years increasing attention has been given to the potential use of contaminated lands for biofuel production, because these degraded soils cannot be used for food production. To establish these crops in Mediterranean contaminated areas, where the soil quality is usually very poor, the addition of soil amendments might be necessary to improve soil productivity. In addition, the use of crops with low water demands, adapted to these particular conditions of climate and soil contamination, is a key requirement. We studied the development of Cynara cardunculus and Silybum mariamun crops (both suitable for the production of biomass for biofuel uses under a Mediterranean climate) in trace element contaminated soils under field conditions. To our knowledge, this is the first such work under these particular experimental conditions (soil contamination and field trial). Soil physical (hydraulic), chemical, and biochemical properties were monitored for one year in experimental plots, where we tested the effects of the addition of two different amendments (sugar lime and biosolid compost) on soil functioning and crop productivity. Seed germination and plant biomass production were low, although amendment addition improved both parameters. The chemical and biological indicators (enzyme activities, PLFA profiles, and soil respiration) tended to be slightly improved by the amendments, especially sugar lime. The hydraulic properties of the soil in the experimental area were very deficient, and the effect of the amendments was not enough to improve them; this was probably the main cause of the general low productivity of these rain-fed crops, as water infiltrated poorly through the root zone. To improve crop productivity under these soil conditions, certain aspects could be improved: higher doses of amendments should be applied and deeper tillage of the soil after amendment addition should be performed to facilitate water infiltration.


Assuntos
Poluentes do Solo , Oligoelementos , Biomassa , Produtos Agrícolas , Solo
6.
Front Plant Sci ; 9: 1682, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30515182

RESUMO

There is an increasing consensus that microbial communities have an important role in mediating ecosystem processes. Trait-based ecology predicts that the impact of the microbial communities on ecosystem functions will be mediated by the expression of their traits at community level. The link between the response of microbial community traits to environmental conditions and its effect on plant functioning is a gap in most current microbial ecology studies. In this study, we analyzed functional traits of ectomycorrhizal fungal species in order to understand the importance of their community assembly for the soil-plant relationships in holm oak trees (Quercus ilex subsp. ballota) growing in a gradient of exposure to anthropogenic trace element (TE) contamination after a metalliferous tailings spill. Particularly, we addressed how the ectomycorrhizal composition and morphological traits at community level mediate plant response to TE contamination and its capacity for phytoremediation. Ectomycorrhizal fungal taxonomy and functional diversity explained a high proportion of variance of tree functional traits, both in roots and leaves. Trees where ectomycorrhizal fungal communities were dominated by the abundant taxa Hebeloma cavipes and Thelephora terrestris showed a conservative root economics spectrum, while trees colonized by rare taxa presented a resource acquisition strategy. Conservative roots presented ectomycorrhizal functional traits characterized by high rhizomorphs formation and low melanization which may be driven by resource limitation. Soil-to-root transfer of TEs was explained substantially by the ectomycorrhizal fungal species composition, with the highest transfer found in trees whose roots were colonized by Hebeloma cavipes. Leaf phosphorus was related to ectomycorrhizal species composition, specifically higher leaf phosphorus was related to the root colonization by Thelephora terrestris. These findings support that ectomycorrhizal fungal community composition and their functional traits mediate plant performance in metal-contaminated soils, and have a high influence on plant capacity for phytoremediation of contaminants. The study also corroborates the overall effects of ectomycorrhizal fungi on ecosystem functioning through their mediation over the plant economics spectrum.

7.
Sci Total Environ ; 625: 50-63, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29289006

RESUMO

Soil contamination by trace elements (TE) is a major environmental problem and much research is done into its effects on ecosystems and human health, as well as into remediation techniques. The Aznalcóllar mine accident (April 1998) was a large-scale ecological and socio-economic catastrophe in the South of Spain. We present here a literature review that synthesizes the main results found during the research conducted at the affected area over the past 20years since the mine accident, focused on the soil-plant system. We review, in depth, information about the characterization of the mine slurry and contaminated soils, and of the TE monitoring, performed until the present time. The reclamation techniques included the removal of sludge and soil surface layer and use of soil amendments; we review the effects of different types of amendments at different spatial scales and their effectiveness with time. Monitoring of TE in soil and their transfer to plants (crops, herbs, shrubs, and trees) were evaluated to assess potential toxicity effects in the food web. The utility of some plants (accumulators) with regard to the biomonitoring of TE in the environment was also evaluated. On the other hand, retention of TE by plant roots and their associated microorganisms was used as a low-cost technique for TE stabilization and soil remediation. We also evaluate the experience acquired in making the Guadiamar Green Corridor a large-scale soil reclamation and phytoremediation case study.


Assuntos
Vazamento de Resíduos Químicos , Mineração , Plantas/metabolismo , Poluentes do Solo/análise , Solo/química , Oligoelementos/análise , Biodegradação Ambiental , Recuperação e Remediação Ambiental , Metais Pesados , Microbiologia do Solo , Espanha
8.
Chemosphere ; 186: 968-976, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28835005

RESUMO

Establishing energy crops could be a cost-efficient alternative towards the valorization of the plant biomass produced in contaminated lands, where they would not compete with food production for land use. Dittrichia viscosa and Silybum marianum are two native Mediterranean species recently identified as potential energy crops for degraded lands. Here, we present the first characterization of the decomposition of the biomass of these species during thermo-chemical conversion (pyrolysis). Using a greenhouse study we evaluated whether the quality of D. viscosa and S. marianum biomass for energy production through pyrolysis could be substantially influenced by the presence of high concentrations of soluble trace element concentrations in the growing substrate. For each species, biomass produced in two different soil types (with contrasted trace element concentrations and pH) had similar elemental composition. Behavior during thermal decomposition, activation energies and concentrations of pyrolysis gases were also similar between both types of soils. Average activation energy values were 295 and 300 kJ mol-1 (for a conversion value of α = 0.5) for S. marianum and D. viscosa, respectively. Results suggest that there were no major effects of soil growing conditions on the properties of the biomass as raw material for pyrolysis, and confirm the interest of these species as energy crops for Mediterranean contaminated lands.


Assuntos
Asteraceae/crescimento & desenvolvimento , Biomassa , Produtos Agrícolas/crescimento & desenvolvimento , Fontes Geradoras de Energia , Silybum marianum/crescimento & desenvolvimento , Carvão Vegetal , Gases/química , Temperatura Alta , Solo/química
9.
PLoS One ; 12(6): e0180240, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28666017

RESUMO

Soil pollution by trace elements (TEs) from mining and industrial activity is widespread and presents a risk to humans and ecosystems. The use of trees to immobilize TEs (phytostabilization) is a low-cost and effective method of soil remediation. We aimed to determine the chemical composition of leaves and flower buds of Eucalyptus camaldulensis in seven sites along the Guadiamar River valley (SW Spain), an area contaminated by a mine-spill in 1998. E. camaldulensis trees in the spill-affected area and adjacent non affected areas were growing on a variety of soils with pH from 5.6 to 8.1 with low concentration of plant nutrients. The spill affected soils contained up to 1069 mg kg-1 of As and 4086 mg kg-1 of Pb. E. camaldulensis tolerated elevated TE concentrations in soil and, compared to other species growing in the same environment, had low TE concentrations in the aerial portions. Besides tolerance to soil contamination, E. camaldulensis had low bioaccumulation coefficients for soil contaminants. TE concentrations in the aboveground portions were below levels reported to be toxic to plants or ecosystems. Flower buds had even lower TE concentrations than leaves. Despite the relatively low concentration of TEs in leaves they were significantly correlated with the soil extractable (0.01 M CaCl2) Cd, Mn and Zn (but not Cu and Pb). The general features of this tree species: tolerance to impoverished and contaminated soils, fast growth and deep root system, and low transfer of TEs from soil to aboveground organs makes it suitable for phytostabilization of soils contaminated by TEs. In addition, eucalyptus leaves could be used for biomonitoring the soil extractability of Cd, Mn and Zn but not Cu or Pb.


Assuntos
Eucalyptus , Poluentes do Solo/análise , Solo/química , Oligoelementos/análise , Biodegradação Ambiental , Ecossistema , Monitoramento Ambiental/métodos , Eucalyptus/química
10.
Sci Total Environ ; 590-591: 29-39, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28288419

RESUMO

The establishment of energy crops could be an option for the management of degraded and contaminated lands, where they would not compete with food production for land use. Here, we aimed to explore the potential of certain native Mediterranean species for the revegetation of contaminated lands for energy production purposes. A field survey was conducted in a trace-element (TE) contaminated area from SW Spain, where the patterns of biomass production, TE accumulation and the calorific value of some thistle species were analyzed along a soil contamination gradient. In a greenhouse experiment the response of two thistle species (Cynara cardunculus and Silybum marianum) and the shrub Dittrichia viscosa to soil contamination was assessed, as well as the effects of these species on some soil microbial parameters involved in nutrient cycling (enzyme activities and arbuscular mycorrhizal colonization in roots). Silybum marianum was able to colonize highly contaminated soils. Its aboveground biomass accumulated Cd and had a relatively high calorific value; this value was similar in biomass obtained from both heavily and moderately contaminated soils. Greenhouse experiment confirmed that S. marianum biomass production and calorific value is scarcely affected by soil contamination. In addition, some soil enzyme activities were clearly enhanced in the S. marianum rhizosphere. Dittrichia viscosa is another promising species, given its capacity to produce a high biomass with appreciable calorific value in acid contaminated soils. Germination of both species was hampered in the acid contaminated soil, and therefore soil pH correction would have to be accomplished before establishing these species on extremely acid soils. Further assessment of the risk of transfer of Cd and other TE to the food chain would be needed to confirm the suitability of these species for the revegetation of contaminated lands with energy production purposes.


Assuntos
Biocombustíveis , Produtos Agrícolas/crescimento & desenvolvimento , Poluentes do Solo/análise , Oligoelementos/análise , Asteraceae/crescimento & desenvolvimento , Biodegradação Ambiental , Biomassa , Cynara/crescimento & desenvolvimento , Silybum marianum/crescimento & desenvolvimento , Solo , Espanha
11.
Sci Rep ; 6: 20018, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26804897

RESUMO

Ecosystems may exhibit alternative stable states (ASS) in response to environmental change. Modelling and observational data broadly support the theory of ASS, however evidence from manipulation experiments supporting this theory is limited. Here, we provide long-term manipulation and observation data supporting the existence of drought induced alternative stable soil moisture states (irreversible soil wetting) in upland Atlantic heath, dominated by Calluna vulgaris (L.) Hull. Manipulated repeated moderate summer drought, and intense natural summer drought both lowered resilience resulting in shifts in soil moisture dynamics. The repeated moderate summer drought decreased winter soil moisture retention by ~10%. However, intense summer drought, superimposed on the experiment, that began in 2003 and peaked in 2005 caused an unexpected erosion of resilience and a shift to an ASS; both for the experimental drought manipulation and control plots, impairing the soil from rewetting in winter. Measurements outside plots, with vegetation removal, showed no evidence of moisture shifts. Further independent evidence supports our findings from historical soil moisture monitoring at a long-term upland hydrological observatory. The results herald the need for a new paradigm regarding our understanding of soil structure, hydraulics and climate interaction.

12.
J Environ Manage ; 161: 276-286, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26197422

RESUMO

The revegetation of polluted sites and abandoned agricultural soils is critical to reduce soil losses and to control the spread of soil pollution in the Mediterranean region, which is currently exposed to the greatest soil erosion risk in Europe. However, events of massive plant mortality usually occur during the first years after planting, mainly due to the adverse conditions of high irradiance and drought stress. Here, we evaluated the usefulness of considering the positive plant-plant interactions (facilitation effect) in the afforestation of polluted agricultural sites, using pre-existing shrubs as nurse plants. We used nurse shrubs as planting microsites for acorns of Quercus ilex (Holm oak) along a gradient of soil pollution in southwestern Spain, and monitored seedling growth, survival, and chemical composition during three consecutive years. Seedling survival greatly increased (from 20% to more than 50%) when acorns were sown under shrub, in comparison to the open, unprotected matrix. Facilitation of seedling growth by shrubs increased along the gradient of soil pollution, in agreement with the stress gradient hypothesis that predicts higher intensity of the facilitation effects with increasing abiotic stress. Although the accumulation of trace elements in seedling leaves was higher underneath shrub, the shading conditions provided by the shrub canopy allowed seedlings to cope with the toxicity provoked by the concurrence of low pH and high trace element concentrations in the most polluted sites. Our results show that the use of shrubs as nurse plants is a promising tool for the cost-effective afforestation of polluted lands under Mediterranean conditions.


Assuntos
Biodegradação Ambiental , Poluição Ambiental , Quercus/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Agricultura , Secas , Europa (Continente) , Concentração de Íons de Hidrogênio , Região do Mediterrâneo , Folhas de Planta/química , Plantas , Plântula/química , Sementes/crescimento & desenvolvimento , Espanha , Oligoelementos/análise
13.
Environ Monit Assess ; 184(4): 2031-43, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21573712

RESUMO

Pasture selection by livestock is an essential topic for rangeland management, especially in trace element-contaminated soils. We have studied the composition (nutrients and trace elements) of a grass-based diet from soils affected by a mine spill at different growth stages (October 2008 to May 2009). A diet based on other plants (mainly Compositae species) was also studied (May 2009) for comparison. Faeces and mane hair of horses feeding on these pastures were also analysed. Micronutrient (Cu, Fe, Mn and Zn) and potentially toxic trace element (As, Cd, Pb, Tl) concentrations were below the maximum tolerable levels (MTL) for horses, except for Fe (at early growth of pastures) and Cd (in the diet based on 'other' plants). Values of potential ingestion of Fe by horses were higher than 10 mg kg body weight(- 1) day(- 1). Cadmium concentrations in some pasture samples (those composed of Compositae species) were higher than 3 mg kg(- 1). Potential toxicity of such Cd levels in pastures is uncertain, since a high disparity of criteria about MTL by cattle exists (between 0.5 and 10 mg kg(- 1) diet). Nutrient concentrations were adequate for horses, which could counteract possible harmful effects derived from trace element ingestion. The analyses of excreta and mane hair point to the low risk of toxicity derived from the consumption of these contaminated pastures. However, the ingestion of regenerating pastures (autumnal samples) should be avoided due to the greater risk of ingestion of contaminated soil attached to the plant material. Management of these pastures by grazing requires periodic monitoring. Special attention should be given to Fe and particularly Cd (non-essential element) which accumulates in animal organs, where it could provoke uncertain long-term effects.


Assuntos
Cádmio/análise , Herbivoria , Cavalos , Chumbo/análise , Plantas/química , Oligoelementos/análise , Animais , Monitoramento Ambiental , Fezes/química , Cabelo/química , Espanha
14.
Chemosphere ; 83(8): 1166-74, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21281955

RESUMO

The impairment of root growth and photosynthetical functioning are the main impacts of trace elements on woody plant seedlings. In this work, we assessed the response of Holm oak (Quercusilex subsp. ballota) and mastic shrub (Pistacia lentiscus) seedlings to high concentrations of Cd and Tl in the rhizosphere. These are non-essential trace elements, with a potential high mobility in the soil-plant system. Seedlings of these species are frequently used in the afforestation of degraded soils in mining areas. Plants were exposed to different levels of Cd (20, 80 and 200 mg L(-1)) and Tl (2, 10 and 20 mg L(-1)) in a sand culture. Biomass allocation, growth rates, chlorophyll fluorescence and gas exchange were studied. Both metals affected root biomass. Cadmium produced an increase in the root mass ratio and a decrease in the specific leaf area of the plants in oak seedlings, while Tl did not provoke such response. Mastic plants were more sensitive to Tl and Cd than oak plants. Between elements, Tl provoked more severe toxic effects in the plants, affecting the antennae complexes and reaction centers of the photosystem II. Both elements decreased net assimilation rates (down to a 20% of the control plants) and stomatal conductance (5-10% of the values for the control plants). Cadmium was highly retained in the roots of both species, while Tl was highly translocated into the leaves. In general, Holm oak showed a higher tolerance for Cd than for Tl, and a higher resistance to both metals than mastic shrub, due to a high capacity for Cd retention at the root level. However, such accumulation in roots may induce water stress in the seedling exposed to Cd.


Assuntos
Cádmio/toxicidade , Pistacia/efeitos dos fármacos , Quercus/efeitos dos fármacos , Rizosfera , Tálio/toxicidade , Biomassa , Cádmio/metabolismo , Clorofila/metabolismo , Fluorescência , Fotossíntese/efeitos dos fármacos , Pistacia/crescimento & desenvolvimento , Pistacia/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Quercus/crescimento & desenvolvimento , Quercus/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Tálio/metabolismo
15.
Chemosphere ; 76(4): 480-6, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19375778

RESUMO

Afforestation of contaminated land by trees is considered as a feasible strategy for the extensive stabilization of contaminants. In this work, we studied the patterns of metal availability (Cd, Cu, Pb and Zn) in a contaminated and afforested area. Specifically, we observed the response of Holm oak (Quercus ilex subsp. ballota) leaves to changes in the availability of metals under field conditions, focusing on Cd. Under controlled conditions we studied the performance of oak seedlings exposed to high levels of Cd, with the aim of analyzing the patterns of translocation and tolerance of the seedlings. Cadmium was the most available metal, in relative terms; 15% of the total Cd in the soil was extracted with NH4NO3. The availabilities of Cd, Cu and Zn showed exponential relationships with soil pH (pH values ranged from 2.4 to 8.4). Cadmium accumulation in the leaves was not related to the changes in Cd availability. Greenhouse studies showed that seedlings had a high Cd retention capacity in fine roots (up to 7 gkg(-1)) and low rates of Cd translocation to the leaves (transfer coefficients below 0.03). Root biomass and thickness was altered by exposure to Cd. In spite of this, the chlorophyll fluorescence measurements (an indicator of plant stress) only differed slightly from the control treatment at a Cd dose of 200 mgL(-1). Due to the relatively high tolerance to Cd and the capacity of roots to retain this metal, Holm oak may be useful for the phytostabilization of soils contaminated by Cd.


Assuntos
Cádmio/metabolismo , Raízes de Plantas/metabolismo , Quercus/metabolismo , Poluentes do Solo/metabolismo , Solo , Biodegradação Ambiental , Biomassa , Cádmio/análise , Folhas de Planta/metabolismo , Plântula/metabolismo , Poluentes do Solo/análise
16.
Environ Pollut ; 152(1): 50-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17602809

RESUMO

Phytomanagement employs vegetation and soil amendments to reduce the environmental risk posed by contaminated sites. We investigated the distribution of trace elements in soils and woody plants from a large phytomanaged site, the Guadiamar Valley (SW Spain), 7 years after a mine spill, which contaminated the area in 1998. At spill-affected sites, topsoils (0-25 cm) had elevated concentrations of As (129 mg kg(-1)), Bi (1.64 mg kg(-1)), Cd (1.44 mg kg(-1)), Cu (115 mg kg(-1)), Pb (210 mg kg(-1)), Sb (13.8 mg kg(-1)), Tl (1.17 mg kg(-1)) and Zn (457 mg kg(-1)). Trace element concentrations in the studied species were, on average, within the normal ranges for higher plants. An exception was white poplar (Populus alba), which accumulated Cd and Zn in leaves up to 3 and 410 mg kg(-1) respectively. We discuss the results with regard to the phytomanagement of trace element contaminated sites.


Assuntos
Metais Pesados/análise , Mineração , Folhas de Planta/química , Poluentes do Solo/análise , Solo/análise , Biodegradação Ambiental , Monitoramento Ambiental/métodos , Espectrometria de Massas , Olea/química , Populus/química , Quercus/química , Espanha , Especificidade da Espécie
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