Browsing by Author "Abreu, M.M."
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- Acumulação e translocação de elementos vestigiais em Cistus ladanifer L. de áreas mineiras da FPI portuguesaPublication . Abreu, M.M.; Santos, Erika; Fernandes, Eliana; Batista, Maria João; Ferreira, MaraThe accumulation and translocation of As, Cu, Pb and Zn in different Cistus ladanifer L. populations colonizing mine areas of Brancanes, Sao Domingos, Chanca and Caveira (Portuguese Iberian Pyrite Belt) and two control areas (Caldeirao and Pomarao) was evaluated. Soils from Sao Domingos and Caveira presented the greatest total concentrations of As, Cu and Pb. Brancanes and Chanca mine areas might be considered in natural attenuation processes relatively to the past mining activity that cessed about one century ago. Plants are, except those from Caveira mine area, Zn accumulators. The concentration of Pb in plants (aerial part) from the control and Sao Domingos areas are within the range considered phytotoxic. Trace elements concentrations in plants are below the domestic animal toxicity limits. Cistus ladanifer might be used in phytostabilization programs of other mine areas as trace elements concentrations in soils did not influence the behaviour of the different plant populations
- Are uranium-contaminated soil and irrigation water a risk for human vegetables consumers ? A study case with Solanum tuberosum L., Phaseolus vulgaris L. and Lactuca sativa L.Publication . Neves, O.; Abreu, M.M.The knowledge of uranium concentration, in the products entering the human diet is of extreme importance because of their chemical hazard to health. Controlled field experiments with potatoes, beans and lettuce (Solanum tuberosum L., Phaseolus vulgaris L. and Lactuca sativa L.) were carried out in a contaminated soil used by local farmers located near a closed Portuguese uranium mine (Cunha Baixa, Mangualde). The soil with high average uranium levels (64–252 mg/kg) was divided in two plots, and irrigated with non-contaminated and uranium-contaminated water (\20 and [900 lg/L). Uranium maximum average concentration in the edible vegetables parts (mg/kg fresh weight) ranged in the following order: lettuce (234 lg/kg)[green bean (30 lg/kg)[potatoes without peel (4 lg/kg). Although uranium in soil, irrigation water and vegetables was high, the assessment of the health risk based on hazard quotient indicates that consumption of these vegetables does not represent potential adverse (no carcinogenic) effects for a local inhabitant during lifetime
- Assessment of pollution risk ascribed to Santa Margarida Military Camp activities (Portugal)Publication . Matias, M.J.; Marques, J.M.; Figueiredo, P.; Basto, M.J.; Abreu, M.M.; Carreira, P.M.; Ribeiro, C.; Flambó, A.; Feliciano, J.; Vicente, E.M.Santa Margarida Military Camp (S.M.M.C.) is the only one Portuguese military training area, including firing ranges for tactical military manoeuvres of mechanised divisions. For this reason, various negative effects on the environment were expected due to the military activities, as the Military Camp’s area is classified as a high vulnerability area to pollution of its multilayer porous aquifers. The aim of this study was to identify and characterise local/regional geochemical impacts caused by the continuing military training activities performed at S.M.M.C. in the course of 52 years. An overview of the geochemical research issues as a basis for risk assessment is presented. A special attention has been put on the quality of local and regional surface waters, shallow groundwaters and groundwaters. Local soils and sediments as well as fragments of shells and bullets were sampled and analysed. The results so far obtained, indicated that none pollution effects were a consequence of the military training activities. Till now, the geochemical signatures such as, high levels of K, Cl and NO3 in waters, detected in particular sites, should be faced as tracers of diffuse pollution ascribed to urban waste disposal and cattle breading.
- Avaliação biogeoquímica dos solos e do medronheiro na área mineira da PanasqueiraPublication . Godinho, B.; Abreu, M.M.; Magalhães, M.C.F.Panasqueira mine is one of the most important mines in Portugal. Over the last century exploration of tungsten, copper and tin has contributed to produce many waste materials that constitute tailings with huge dimensions generating high visual and chemical impacts. The objective of this work was to study the biogeochemical impact of mining on the soils and arbutus trees (Arbutus unedo) in this area
- Comparação de correctivos aplicados a um solo de uma área mineira contaminado com arsénio e seu efeito no crescimento de plantasPublication . Madeira, A.C.; Esteves, C.; Abreu, M.M.; Varennes, A.; Magalhães, M.C.F.Three amendments (iron oxides, Fe; organic matter, MO; calcium phosphate, PCa) were applied to a naturally contaminated soil with arsenic and their effect on the growth of tomato plants and Italian parsley was studied. The results indicate differences associated with the availability of arsenic in the soil in the presence of amendments: Fe had no influence on arsenic availability compared with the unamended soil, while MO and PCa increased the avalability of arsenic.
- Disponibilidade de Cu, Pb e Zn nas áreas mineiras de Canal Caveira e São Domingos - faixa piritosa IbéricaPublication . Santos, E.S.; Abreu, M.M.; Ferreira, M.B.; Magalhães, M.C.F.Several mining areas are abandoned in the Iberian pyrite belt (IPB) leading to important points of environmental contamination. The potential and immediate environmental risk and impact on public health of hazardous elements from soil can be estimated from availability analysis. The aim of this study was to evaluate the availability of Cu, Pb and Zn in São Domingos and Canal Caveira mining areas located in the IBP.
- Evaluation of amendments in the rehabilitation of sulfide mine tailings from São DomingosPublication . Abreu, M.M.; Varennes, A.; Santos, E.S.; Macias, F.The São Domingos mining area is located in the Iberian Pyrite Belt, SE Portugal, and represents a serious environmental hazard (Matos and Martins, 2006). Exploitation dated back to pre-roman and roman times with extraction of Ag, Au and Cu exploitation, mainly in the gossan (resulting from the ore weathering). The intense exploitation started in the middle of 19th century, both in the gossan and sulfide ore-containing Cu, Zn, As and Pb, and lasted until 1960, with the exhaustion of the ore (Quental et al., 2002). Different types of waste materials were left: gossan, host rocks (volcanic with shales, and shales), roman and modern slags, smelting ashes and brittle and blocks of pyrite (Matos, 2004; Álvarez-Valero et al., 2008). All sulfide mine wastes are typically heterogeneous and contain high amounts of trace elements, acidic pH and small contents of organic matter and nutrients. The large dumps containing pyrite and other metal sulfides generate, by oxidation, acidic mine drainage (AMD) which increases the availability of trace elements for microorganisms and plants in the surrounding soils. All of these characteristics contribute towards a system that is barely capable of supporting the establishment or survival of plants. The use of amendments and spontaneous colonization (vegetation) from mining areas (phytostabilization) are cost-effective and environmentally sustainable methods to rehabilitate these contaminated and degraded areas even in arid and semi-arid conditions (Tordoff et al., 2000; Mendez and Maier, 2008). Thus, the preparation of Technosols from mixtures of organic and inorganic wastes can be an attractive option to rehabilitate mining areas because they can improve physical, chemical and biological properties contributing, at the same time, towards a strategy of wastes valorisation (Macías, 2004). The use of mixtures composed of residues with different C:N ratios can be used to manipulate the rate of mineralization. Nevertheless, the amendments used should also promote other soil functions (Arbestain et al., 2008). The objective of this study was to evaluate the influence of cost-effective organic and inorganic amendments, available in the region, in the rehabilitation of sulfide materials from the São Domingos mine area
- Evaluation of trace elements mobility from soils to sediments between the Iberian pyrite belt and the Atlantic OceanPublication . Batista, M.J.; Abreu, M.M.; Locutura, J.; Oliveira, D. de; Matos, J.X.; Silva, C.; Bel-Lan, A.; Martins, L.An environmental study was conducted in 193 stream sediments and 355 soil samples collected in the lower section of Guadiana River Basin to evaluate the trace elements transfer from one compartment into another. The objective was to evaluate the dispersion of Pb, Cu, Zn and other chemical elements resulting from upstream mines into the lower N-S sector of the Guadiana River Basin to the Atlantic Ocean. The area partly includes the Iberian Pyrite Belt, a known volcanogenic massive sulphide (VMS) province with important mining activity history. Median concentrations of the elements Cu, Pb, Zn, Al, As, Ba, Br, Ca, Mg, Mn and Na are generally higher in the studied sediments than in soils. Soils are normally acidic and mobility of elements is in these conditions higher. When the relations between upstream soils and downstream sediments were established, median values were higher in the upstream soils only for elements such as Co, Ni, K, Pb, Mn and Ti, probably the less mobile, and the Cu, Zn, Al, As, Ba, Br, Ca, Cr, Fe, Mg and Na have highest concentrations in the downstream sediments. Lead was considered the less mobile element and Zn the highly mobile of the base metals in the mining area of the lower Guadiana River. Dispersion of the metals, considering the studied soil and sediment samples is partially restricted to the mining areas or downstream sediments but close to the mine sources, where ore tailings and acid waters occur. Near the mouth, concentrations of As, Cu, Pb and Zn increase in relation with mining and other pollution sources. Interaction with salt water forces chemical elements precipitation from water and subsequent increase of their concentration in sediments. This may be the reason for the increase of those chemical elements concentrations in the sediments
- Fraccionamento do crómio no horizonte Ap de um lixissolo férreo e de um luvissolo estágnico após enriquecimento em Cr (III)Publication . Joaquim, C.; Abreu, M.M.; Fernandes, M.L.
- Impacts on water, soil and plants from the abandoned Miguel Vacas copper mine, PortugalPublication . Abreu, M.M.; Matias, M.J.; Magalhães, M.Clara F.; Basto, M.J.Soil, water and plant geochemistry was studied around the Miguel Vacas copper mine (Alentejo, SE Portugal), which stopped its exploitation and processing activities in 1991. After closure waste-rock piles remained exposed to weathering. The copper ore was mainly composed of copper phosphates and carbonates. Remediation actions were insufficient to prevent the spreading of waste-rock materials to surrounding farmed fields. The latter caused contamination of soils and water. Based on overall characteristics water from wells and surface stream water mostly can be classified as of the sulphate magnesium type. The application of a chemical equilibrium model to the sampled water showed that copper, phosphate and sulphate concentrations are controlled by copper(II) secondary minerals (pseudomalachite, libethenite and malachite) and gypsum. Nevertheless, groundwater can be used for irrigation and cattle based on quality parameters. Soils and plants (Prunus domestica L., Olea europaea L. spp. europaea and Quercus ilex L.) were collected southeast of the open pit and the exploitation substructures. The soils located in the influence of drainage water that percolated through waste material or exploitation substructures were contaminated with Cu, and Ni was close to the maximum value allowed by Portuguese legislation. These soils, however, did not show elevated Zn and Mn concentrations. The trace element content in plants was within the normal range, with Q. ilex being able to accumulate Mn and to some extent also Ni. Dispersion of trace elements seemed to be limited to a distance 1500 m down from the waste dumps in southeastern direction.