Browsing by Author "Marques, Ana P. G. C."
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- Application of maize and efficient rhizospheric microorganisms for the remediation of saline soilsPublication . Moreira, Helena; Pereira, Sofia A.; Vega, Alberto L.; Castro, Paula M. L.; Marques, Ana P. G. C.Soil salinity is a serious problem causing loss of fertility, as plants facing salt stress suffer alterations in physiology that adversely affects its growth. This work aimed to evaluate the effectiveness of combinations of microorganisms for the recovery of crop productivity in soils affected by different levels of salinity (0, 2.5 and 5 gNaCl.kg-1). The strategy relied on the culture in greenhouse conditions of a high value food and energetic crop (maize) inoculated with soil plant growth promoting microbiota – an arbuscular mychorrizal fungi (Rhizophagus irregularis), a rhizobacteria (Pseudomonas reactans) and a bacterial endophyte (Pantoea ananatis). Plant biomass was assessed at harvest and differences between treatments were analysed. As the work also aimed to relate the effects of bioinoculation to alterations in plant response to salt stress, further parameters were assessed. Elevated salt levels induce ionic stress, with consequent nutrient imbalance; therefore, levels of Na, K and Ca were determined in plant tissues. As salt is also a major stress to soil organisms, rhizosphere samples were analysed to follow up of microbiota survival by molecular biology techniques (DGGE), assessing the effect of soil salinity at the different tested levels on the inoculated soil microorganisms persistence and relationship with the existing community. The collected information allowed understanding the effects of the applied biologically based treatments in the quality of the tested saline soils, on the dynamics of the present microbiota and on maize growth, focusing on the further development of cropping strategies for saline soils, grounded on sustainable agriculture practices.
- Application of manure and compost to contaminated soils and its effect on zinc accumulation by Solanum nigrum inoculated with arbuscular mycorrhizal fungiPublication . Marques, Ana P. G. C.; Oliveira, Rui S.; Rangel, António O. S. S.; Castro, Paula M. L.
- Application of manure and compost to contaminated soils and its effect on zinc accumulation by Solanum nigrum inoculated with arbuscular mycorrhizal fungiPublication . Marques, Ana P. G. C.; Oliveira, Rui S.; Rangel, António O.S.S.; Castro, Paula M. L.
- Application of manure and compost to contaminated soils and its effect on zinc accumulation by Solanum nigrum inoculated with arbuscular mycorrhizal fungiPublication . Marques, Ana P. G. C.; Oliveira, Rui S.; Rangel, António O. S. S.; Castro, Paula M. L.Zn accumulation in Solanum nigrum grown in naturally contaminated soil in the presence of different types of organic amendments was assessed. Under the same conditions, the response of the plant to inoculation with two different isolates of arbuscular mycorrhizal fungi (AMF) (Glomus claroideum and Glomus intraradices) was also evaluated. S. nigrum grown in the non-amended soil always presented higher Zn accumulation in the tissues, with the addition of amendments inducing reductions of up to 80 and 40%, for manure and compost, respectively, and enhancing plant biomass yields. The establishment of S. nigrum in the Zn contaminated soil combined with the application of amendments led to a 70-80% reduction in the amount of Zn leached through the soil. The use of S. nigrum in combination with manure appeared as an effective method for reducing the effects of soil contamination, diminishing Zn transfer to other environmental compartments via percolation.
- Arbuscular mychorrizal fungi assisted Zn uptake by Solanum nigrumPublication . Marques, Ana P. G. C.; Oliveira, Rui S.; Rangel, António O. S. S.; Castro, Paula M. L.
- Arbuscular mychorrizal fungi assisted ZN uptake by Solanum nigrumPublication . Marques, Ana P. G. C.; Oliveira, Rui S.; Rangel, António O. S. S.; Castro, Paula M. L.
- Arsenic, lead and nickel accumulation in Rubus ulmifolius growing in contaminated soil in PortugalPublication . Marques, Ana P. G. C.; Moreira, Helena; Rangel, António O.S.S.; Castro, Paula M.L.This work investigates the potential of Rubus ulmifolius, indigenous to ametal contaminated site – Esteiro de Estarreja – for phytoremediation purposes. The site has a long history of metal contamination. The accumulation of lead (Pb), arsenic (As) and nickel (Ni) in different sections – roots, stems and leaves – of the plant was assessed and compared to the levels of those metals in the soil and in the available fraction. The distribution of metals throughout the area was quite heterogeneous, presenting levels of As, Pb and Ni of up to 3078, 1400 and 135mg kg¯¹, respectively, and the metal content in the sections of R. ulmifolius collected in the banks of the stream varied among sites of collection. Levels of metals were higher in the plant roots: As levels (mg kg¯¹) ranged from 277 to 1721 in the roots, 30 to 110 in the stems, and 60 to 265 in the leaves; Pb concentrations (mg kg¯¹) ranged from 248 to 1178 in the roots, 35 to 133 in the stems, and 25 to 149 in the leaves; and Ni (mg kg¯¹) ranged from 48 to 151 in the roots. Significant correlations were found between the total levels of Pb and As in the soil and the levels in the roots of the plant; further correlations between total and available levels in the soil and metals in other plant tissues were generally found as non-significant. According to the metal accumulation patterns of R. ulmifolius, this species seems to be valuable for application in phytostabilisation strategies.
- Assessment of the biofuel production potential from phytoremediation sunflower biomassPublication . Marques, Ana P. G. C.; Domingues, Patrícia; Prata, Nuno; Castro, P. M. L.; Caetano, N. S.There are presently more than 3 million contaminated sites all over EU, according to the EEA (report 25186 EN). Heavy metal contamination is of particular concern, as metals are not degradable. Phytoremediation is gaining attention from the public and is an attractive low cost alternative for soil requalification, by establishing a vegetation cover which will stabilize the site, avoiding dispersion of contamination and simultaneously removing pollutants. Although the fate of harvested biomass is a common obstacle for its implementation, it may represent an opportunity for producing energy. This work presents a novel integrated strategy comprising the utilization of all plant parts for the generation of biodiesel. Combinations of sunflower and plant growth promoting microbiota were assessed growing in agricultural and metal contaminated soils. Harvested plant tissues were analysed and it was possible to observe that accumulation of Zn and Cd was made mainly in the roots, followed by the stems and the flowers, with the values registered for plants grown in contaminated soils being higher than the reported phytotoxic levels described in literature. Also, plants grown in the agricultural soil presented higher biomass rates. Sunflower seeds were then used for oil extraction and it was possible to observe efficiencies of up to 20 ml oil/m2, with only the oil from plants grown in industrial soil presenting levels of 1.8 mg Zn/l. Plant stems were used for bioethanol fermentation with yields of up to 280 and 162 ml/m2 for plants growing respectively in agricultural and industrial soils. Once again only plants grown in the industrial soil presented detectable levels of 1.1 mg Zn/l (and no Cd).
- Assessment of the biofuel production potential from phytoremediation sunflower biomassPublication . Marques, Ana P. G. C.; Domingues, Patrícia; Prata, Nuno; Caetano, Nídia S.; Castro, Paula M. L.There are presently more than 3 million contaminated sites all over EU, according to the EEA (report 25186 EN). Heavy metal contamination is of particular concern, as metals are not degradable. Phytoremediation is gaining attention from the public and is an attractive low cost alternative for soil requalification, by establishing a vegetation cover which will stabilize the site, avoiding dispersion of contamination and simultaneously removing pollutants. Although the fate of harvested biomass is a common obstacle for its implementation, it may represent an opportunity for producing energy. This work presents a novel integrated strategy comprising the utilization of all plant parts for the generation of biodiesel. Combinations of sunflower and plant growth promoting microbiota were assessed growing in agricultural and metal contaminated soils. Harvested plant tissues were analysed and it was possible to observe that accumulation of Zn and Cd was made mainly in the roots, followed by the stems and the flowers, with the values registered for plants grown in contaminated soils being higher than the reported phytotoxic levels described in literature. Also, plants grown in the agricultural soil presented higher biomass rates. Sunflower seeds were then used for oil extraction and it was possible to observe efficiencies of up to 20 ml oil/m2, with only the oil from plants grown in industrial soil presenting levels of 1.8 mg Zn/l. Plant stems were used for bioethanol fermentation with yields of up to 280 and 162 ml/m2 for plants growing respectively in agricultural and industrial soils. Once again only plants grown in the industrial soil presented detectable levels of 1.1 mg Zn/l (and no Cd).
- Assessment of the energy production potential form phytoremediation derived biomassPublication . Marques, Ana P. G. C.; Castro, Paula M. L.; Caetano, Nídia S.There are presently more than 3 million contaminated sites all over EU, according to the EEA (report 25186 EN). Heavy metal (HM) contamination is of particular concern, as metals are not degradable. Phytoremediation is gaining attention from the public and is an attractive low cost alternative for soil requalification, by establishing a vegetation cover which will stabilize the site, avoiding dispersion of contamination and simultaneously removing pollutants. Although the fate of harvested biomass is a common obstacle for its implementation, it may represent an opportunity for producing energy. However, and although it has been proposed theoretically as an excellent option, the information available in literature concerning practical applications is scarce, despite the considerable degree of success reported. The use of biomass grown in degraded and abandoned soils, not involving agricultural soils for energy crop cultivation, may increase the sustainability of utilizing biomass for energy generation, while it may allow for increasing the available agricultural soil through the consequent gradual decontamination of such brownfields. This work presents a novel integrated strategy comprising the utilization of all plant parts for the generation of biodiesel. Combinations of sunflower and plant growth promoting microbiota were assessed growing in agricultural and metal contaminated indutrial soils, and monitored to further understand the effects on crop productivity and soil remediation. Harvested plant tissues were used for oil extraction and bioethanol production. The quality of the generated products was assessed to understand the effect of the HM soil contamination.