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- Effect of arsenic, lead and zinc on seed germination and plant growth in black nightshade (solanum nigrum l.) vs. clover (trifolium incarnatum l.)Publication . Marques, Ana P. G. C.; Rangel, António O. S. S.; Castro, Paula M. L.S. nigrum was found to proliferate in sediments with high levels of metal pollution. Toxicity tests were performed using seed germination, root elongation, shoot length and biomass as parameters for establishing growth inhibition of S. nigrum and T. incarnatum by arsenic, lead and zinc. All the elements had a higher inhibitory action on the ger-mination and growth of T. incarnatum – inhibition occur-ring at 3 mg element per kg of dry sand. S. nigrum presented germination and growth at higher concentrations of those elements - 7 mg Pb kg-1, 10 mg Zn kg-1 and 10 mg As kg-1. Although inhibitory concentrations for each plant were dif-ferent, increasing the elements concentration reduced seed germination, root elongation and shoot length in T. incar-natum, but not always in S. nigrum. For the latter, low con-centrations (3 mg kg-1 dry sand) of Zn and As seemed to have stimulatory effects on germination. The addition of nu-trients did not cause a significant (P < 0.05) difference in the germination of both plants, except for high metal/ metal-loid concentration in S. nigrum. Concerning growth char-acteristics, nutrient addition was only a differentiation factor for shoot length at low metal/metalloid concentrations. S. nigrum could be a promising plant to be used in further ex-periments concerning the potential of phytoremediation of metal contaminated sites, as long as an adequate planting strategy is followed.
- 2-Fluorophenol degradation by aerobic granules in a sequencing batch reactorPublication . Duque, A. F.; Bessa, V. S.; Carvalho, M. F.; De Kreuk, M. K.; Loosdrecht, M. C. M. van; Castro, P. M. L.
- Evaluation of different substrates in constructed wetlands planted with Typha latifolia for the treatment of tannery wastewaterPublication . Calheiros, Cristina S. C.; Rangel, António O. S. S.; Castro, Paula M. L.
- Ecotechnologies as urban solutions for sustainable water managementPublication . Calheiros, Cristina S. C.; Monteiro, Cristina M.; Rangel, António O. S. S.; Castro, Paula M. L.
- Long-term stability of a non-adapted aerobic granular sludge process treating fish canning wastewater associated to EPS producers in the core microbiomePublication . Paulo, Ana M. S.; Amorim, Catarina L.; Costa, Joana; Mesquita, Daniela P.; Ferreira, Eugénio C.; Castro, Paula M. L.The tolerance of aerobic granular sludge (AGS) to variable wastewater composition is perceived as one of its greatest advantages compared to other aerobic processes. However, research studies select optimal operational conditions for evaluating AGS performance, such as the use of pre-adapted biomass and the control of wastewater composition. In this study, non-adapted granular sludge was used to treat fish canning wastewater presenting highly variable organic, nutrient and salt levels over a period of ca. 8 months. Despite salt levels up to 14 g NaCl L−1, the organic loading rate (OLR) was found to be the main factor driving AGS performance. Throughout the first months of operation, the OLR was generally lower than 1.2 kg COD m−3 day−1, resulting in stable nitrification and low COD and phosphorous levels at the outlet. An increase in OLR up to 2.3 kg COD m−3 day−1 disturbed nitrification and COD and phosphate removal, but a decrease to average values between 1 and 1.6 kg COD m−3 day−1 led to resuming of those processes. Most of the bacteria present in the AGS core microbiome were associated to extracellular polymeric substances (EPS) production, such as Thauera and Paracoccus, which increased during the higher OLR period. Ammonium-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) species were detected in AGS biomass; while AOB were identified throughout the operation, NOB were no further identified after the period of increased OLR. Different polyphosphate-accumulating organisms (PAOs) were detected along the process: Candidatus Accumulibacter, Tetrasphaera and Gemmatimonas. A non-adapted granular sludge was able to treat the fish canning wastewater and to tolerate salinity fluctuations up to 14 g L−1. Overall, a high microbial diversity associated to EPS producers allowed to preserve bacterial groups responsible for nutrients removal, contributing to the adaptation and long-term stability of the AGS system.
- Biodegradation of chiral pharmaceuticals by an activated sludge consortium followed by a Chiral HPLC-FDPublication . Ribeiro, Ana R.; Castro, P. M. L.; Afonso, Carlos; Tiritan, MariaBiodegradation tends to be enantioselective in contrast to abiotic degradation and it is necessary enantioselective analytical methods to quantify the enantiomeric fraction of chiral pharmaceuticals in the environment for correct risk assessment. In this work, we developed HPLC-FD methods to follow the biodegradation of four beta-blockers: alprenolol , propranolol , metoprolol and atenolol and the antidepressant fluoxetine during 15 days in batch mode. The biodegradation assays were performed using AS from the aerated tanks of a municipal wastewater treatment plant with a singly compound supplementation and a mixture compound supplementation similar to those found in wastewater influents. Abiotic degradation in the presence of light and in the dark was evaluated. Either the low concentration or the mixture effects are situations closer to those found in the environment. The results indicate the higher degradation extents for the S-enantiomer forms, as is shown in Figure 1.
- Bioremediation on anthropogenic affected areas: Ectomycorrhizal and plant growth bacteria as promoters of pine establishmentPublication . Franco, Albina R.; Sousa, Nadine R.; Ramos, Miguel A.; Castro, Paula M. L.The recovery of damaged areas due to inadequate farming policies and increased industrial sediment deposition, have contaminated not only soil and surrounding areas but also other natural resources. The potential use of disturbed sites for agriculture and forestry is jeopardised and their remediation is critical and expensive. The utilization of biotechnological tools, such as plant growth promoting bacteria (PGPB) and ectomycorrhizal fungi (ECM) could help remediation of such soils as they can be used as plant facilitators for land recovery. The aim of this study was to assess the potential of PGPB and ECM to enhance the growth of Pinus pinaster in antropogenic sediments and forest soil. Pine seedlings were inoculated with Suillus bovinus, Pisolithus tinctorius and Paxillus involutus, and co-inocualted with Bacillus spp. and Mesorhizobium spp. Plants were harvested after 6 month growth and parametric and nutritional data determined. Results show that P. involutus increased seedling growth(height) in industrial sediments soil, whereas in forest soil, plant performance was higher with S. bovinus. The effect of inoculation on the fungal communityin seedling roots and bacterial rhizosphere was also analysed by PCR-DGGE and differences arose between inoculated and uninoculated soil, indicating that PGPB and ECM may significantly influence the plant growth performance over a period of time. The study shows that PGPB and ECM fungi may be used as a biotechnology tool contributing to the successful plant establishment in disturbed environments.
- Microbial community in a biofilter traeting odours from an organic recovery plant for municipal solid waste treatmentPublication . Bessa, Vânia S.; Moura, S. C.; Baptista, I. I. R.; Jorge, R. Ferreira; Castro, P. M. L.
- Phenotypic evaluation of the IDC profile of soybean plants after inoculation with plant growth-promoting bacteriaPublication . Castro, Paula M. L.; Carvalho, Susana M. P.; Vasconcelos, Marta W.; Roriz, Mariana
- Succession dynamics of ectomycorrhizal fungi in inoculated Quercus rubra seedlings – a field studyPublication . Franco, Albina R.; Ramos, Miguel A.; Sousa, Nadine R.; Oliveira, Rui S.; Castro, Paula M. L.Selected ectomycorrhizal (ECM) fungi may have a beneficial effect on the establishment of nursery grown seedlings and may influence their survival on the first years. By increasing seedling capacity to capture nutrients, ECM fungi often contribute to a successful plant establishment. We investigated the performance of pre-inoculated Quercus rubra seedlings on a reforestation site and monitored ECM fungal persistence and succession dynamics between selected ECM fungi and native fungal community. Nursery grown Q. rubra seedlings inoculated with a mixture of ECM fungi (Cenococcum geophilum, Hebeloma crustuliniforme, H. mesophaeum, H. velutipes, Paxillus involutus, Scleroderma citrinum) and non-inoculated control oak seedlings, were transplanted to Serra da Cabreira in Northern Portugal. Two years after planting, the subsistence of the inoculated ECM fungi was assessed using ITS-DGGE. Results demonstrated that inoculation with selected ECM fungi at nursery stage promoted the establishment and improved the growth performance of out planted oak seedlings. C. geophilum was significantly associated with inoculated saplings but other ECM fungi species were also found. Moreover, ECM fungal communities of inoculated and non-inoculated samples are significantly different. Further monitoring is required to increase knowledge on the persistence of ECM fungal communities and their succession dynamics.