Soil microbiota benefits from phytoremediation coupled to metal-resistant rhizobacteria

Phytoremediation is used for requalifying soils contaminated with heavy metals (HM). Sunflower (Helianthus annuus L.) is one of the most studied species for the remediation of HM-contaminated soils. To increase the bioavailability of nutrients and of metals in soils, metal-resistant plant growth promoting rhizobacteria (PGPR), can be associated to phytoremediation strategies. Soil microbiota can benefit from this association, due to the reduced exposure to HMs toxic effect. In this study, next-generation sequencing (NGS) was applied for investigating shifts in soil microbial community after HMs remediation by sunflowers from a soil amended with Cupriavidus sp. strain 1C2. Sunflower was also grown in a non-contaminated soil (control). Actinobacteria were dominant while Proteobacteria was the second most abundant phylum in both soils. Acidobacteria and Nitrospirae were present in higher relative abundance in the control soil. Results have shown that phytoremediation associated to PGPR induced changes in the contaminated soil microbial community: Acidobacterium (Acidobacteria phylum) and Nitrospira (Nitrospirae phylum) bacterial genera increased their abundance at the end of plant growth. These changes did not occur in the control soil, which presented a more stable bacterial community throughout the experiment. This research increases our knowledge on the relationship between soil microbiota and phytoremediation strategies achievements.info:eu-repo/semantics/publishedVersio

Biomethane production from phytoremediation derived maize biomass via anaerobic digestion

info:eu-repo/semantics/publishedVersio

The contact in foster car of children and young people: A current evaluation

No campo das múltiplas interações que ocorrem no acolhimento familiar, destaca-se a relação entre a criança acolhida e a família biológica, pelo impacto que tem no desenvolvimento da criança. Esta relação gera um conjunto de ligações que pode proporcionar ou dificultar à criança a possibilidade de partilhar valores, experiências e conselhos entre aqueles dois mundos. A manutenção das relações pessoais entre os pais e a criança acolhida é um direito de ambos, exceto se contrariar o interesse superior da criança, já que o corte abrupto das relações estabelecidas interfere na organização dos vínculos futuros. O presente artigo resulta da investigação em curso, no distrito do Porto, intitulado «Contacto no acolhimento familiar: padrões, resultados e modelos de gestão», no âmbito de atuação do InEd, o Centro de Investigação e Inovação em Educação da Escola Superior de Educação do Instituto Politécnico do Porto. Este estudo tem como objetivo analisar os resultados do contacto entre a criança em acolhimento familiar e a sua família de origem, bem como as causas da sua inexistência ou cessação. Os resultados preliminares evidenciam que a maioria das crianças e jovens têm contacto com a sua família de origem, ocorrendo em quase 50% dos casos na casa da família de acolhimento, mas nem sempre com a regularidade desejada. Apesar do impacto do contacto na criança ou jovem ser muito diversificado, a maioria manifesta reações emocionais e comportamentais positivas. Por fim, apresentam se implicações para a prática dos técnicos envolvidos neste fenómeno.Among the multiple interactions in foster care, the relationship between the foster child and the biological family is relevant because of the impact produced on the child’s development. The relationship leads to the development of a set of links that can provide or hinder the child’s possibility for sharing values, experiences and knowledge between those two worlds. The maintenance of personal relationships between parents and foster child is a common right, unless it is against the child’s best interests, since the abrupt rupture of established relationships interfere with the organization of future bonds. This article results of an ongoing process of research in district of Oporto, entitled «Contact in foster care: patterns, results and management models» within the scope of action of the InEd, the Center for Research and Innovation in Education, School of Education of the Polytechnic Institute of Porto. This study aims to analyze the results of the contact between the child in foster care and their family of origin as well as the causes of their absence or termination. Preliminary results indicate that the majority of children and young people have contact with their family of origin, occurring in almost 50 % of cases in the house of the foster family, but not always with the desired regularity. Although the impact of contact on the child or young person can be very diverse, the majority has shown positive behavioral and emotional reactions. Finally, it is presented implications for the practice of the technicians involved in this phenomenon

Phytomanagement of Zn- and Cd-contaminated soil: helianthus annuus biomass production and metal remediation abilities with plant-growth-promoting microbiota assistance

Mining and industrial activity are contributing to the increase in heavy metal (HM) pollution in soils. Phytoremediation coupled to selected rhizosphere microbiota is an environmentally friendly technology designed to promote HM bioremediation in soils. In this study, sunflower (Helianthus annuus L.) was used together with Rhizophagus irregularis, an arbuscular mycorrhizal fungi (AMF), and Cupriavidus sp. strain 1C2, a plant growth promoting rhizobacteria (PGPR), as a phytoremediation strategy to remove Zn and Cd from an industrial soil (599 mg Zn kg−1 and 1.2 mg Cd kg−1). The work aimed to understand if it is possible to gradually remediate the tested soil while simultaneously obtaining significant yields of biomass with further energetic values by comparison to the conventional growth of the plant in agricultural (non-contaminated) soil. The H. annuus biomass harvested in the contaminated industrial soil was 17% lower than that grown in the agricultural soil—corresponding to yields of 19, 620, 199 and 52 g m−2 of roots, stems, flowers and seeds. It was possible to remove ca. 0.04 and 0.91% of the Zn and Cd of the industrial soil, respectively, via the HM accumulation on the biomass produced. The survival of applied microbiota was indicated by a high root colonization rate of AMF (about 50% more than in non-inoculated agricultural soil) and identification of strain 1C2 in the rhizosphere at the end of the phytoremediation assay. In this study, a phytoremediation strategy encompassing the application of an energetic crop inoculated with known beneficial microbiota applied to a real contaminated soil was successfully tested, with the production of plant biomass with the potential for upstream energetic valorisation purposes.info:eu-repo/semantics/publishedVersio

Monitoring of biological wastewater treatment processes using indirect spectroscopic techniques

Dissertação de mestrado em Gestão AmbientalReal-time monitoring can enhance the performance of biological wastewater treatment processes by preventing incidents that can lead to the imbalance of the system and eventually to the total loss of biological activity. For this purpose, in-situ monitoring techniques should not require sample pre-treatment and chemicals addition. Nowadays automation is still limited by poor sensor performance and high maintenance costs. Hence, further investigation is required in order to achieve new developments in monitoring techniques. Spectroscopic methods together with chemometrics are being presented as a powerful tool for process monitoring and control, since they can be fast, non-destructive and without the use of chemicals. In this work, UV-Visible and Near-Infrared (NIR) spectroscopy were used to monitor an activated sludge process using immersion probes connected to the respective spectrophotometers through optical fibbers. During two monitoring periods changes were induced to the system to test the ability of both probes in detecting them. While UV-Visible spectroscopy showed to be suitable for on-line monitoring, by detecting chemical oxygen demand (COD) variations in the effluent and identifying different nitrification status, NIR range also demonstrated potentialities, however, due to several experimental constrains, the results were not conclusive. Partial least squares (PLS) regression was performed for the prediction of COD, nitrate and total suspended solids (TSS) concentrations in the effluent using immersible UV-Visible probe and off-line spectra acquisition. The best results were obtained for the in-situ technique. The root mean squared error of cross validation (RMSECV) obtained for the estimative of each parameter was 15.4 mg O2/L for COD, 19.0 mg N-NO3 -/L for nitrate and 35.3 mg/L for TSS. In-situ UV-Visible range proved to be valuable for the monitoring and control of biological wastewater treatment processes, although some improvements identified in this work are still needed to overcome its limitations.A monitorização em tempo real permite melhorar o desempenho dos processos de tratamento biológico de efluentes através da prevenção de incidentes que levam ao desequilíbrio do sistema e eventual perda da actividade biológica. Entre outras vantagens, as técnicas de monitorização in-situ podem ainda evitar a necessidade de efectuar o prétratamento da amostra e a adição de produtos químicos. Actualmente, a automação encontra-se ainda limitada pelo fraco desempenho e elevados custos de manutenção dos sensores. Deste modo, torna-se necessária mais investigação de modo a desenvolver novas técnicas de monitorização. Os métodos espectroscópicos aliados à quimiometria têm sido apresentados como técnicas com uma enorme potencialidade para a monitorização e controlo de processos, uma vez que podem ser rápidos, não destrutivos e não utilizam produtos químicos. Neste trabalho, as regiões do UV-Visível e do Infra-Vermelho Próximo (Near Infra-Red – NIR) foram usadas na monitorização de um processo de lamas activadas através do uso de sondas ligadas, por fibras ópticas, aos respectivos espectrofotómetros. Durante dois períodos de monitorização foram induzidas alterações ao sistema de forma a testar a capacidade de ambas as sondas na detecção destas variações. A espectroscopia do UV-Visível demonstrou ser adequada para a monitorização em linha, ao detectar variações de carência química de oxigénio (CQO) no efluente e ao identificar diferentes fases do processo de nitrificação. Apesar de a espectroscopia na gama NIR ter mostrado potencialidades, devido a diversas limitações experimentais os resultados foram inconclusivos. A técnica de regressão dos mínimos quadrados parciais (partial least squares – PLS) foi utilizada com o objectivo de prever as concentrações da CQO, nitrato e sólidos suspensos totais (SST) no efluente através da sonda de UV-Visível submersível e da aquisição de espectros em diferido. Os melhores resultados foram obtidos com a técnica insitu. O erro médio de validação (RMSECV) obtido para a estimativa de cada um dos parâmetros foi de 15.4 mg O2/L para a CQO, 19.0 mg N-NO3 -/L para o nitrato e 35.3 mg/L para os SST. A técnica UV-Visível in-situ demonstrou ser adequada para a monitorização e controlo de processos de tratamento biológico de efluentes, apesar de ter sido identificada neste trabalho a necessidade de melhorias, por forma a ultrapassar as suas limitações

Bacterial diversity shifts in AGS reactor treating food industry wastewater

Aerobic granular sludge (AGS) is a promising technology for treating industrial wastewater, possessing higher biomass retention and tolerance to toxic substrates than conventional activated sludge systems. AGS presents a diverse microbial community responsible for the simultaneous removal of carbon and nutrients. These communities are protected by extracellular polymeric substances (EPS) that allow for the compact structure of the granules. As a result, bacteria present in the aerobic granules are more resistant to variable wastewater composition, as commonly produced in food industry. The main objective of this work is to study the microbial community dynamics of an AGS reactor treating wastewater from a fish canning plant. The reactor was monitored during 220 days, divided into eight operational phases. COD, NH4+ and PO43- removal were assessed and biomass samples were collected throughout time for microbiome profiling. The reactor presented good COD, PO43- and NH4+ removal during phases I, II and III, but decreased performance during phase IV, when a higher organic load was applied. The removal processes recovered after phase IV until the end of operation. Proteobacteria were dominant in the inoculum (relative abundance of 64.8 %) and dominated almost all reactor phases. Bacteroidetes were second dominant in the inoculum (17.5 %) as well in most reactor phases, being present with higher relative abundance (55.5 %) than Proteobacteria (38.4 %) during phase IV. Within Proteobacteria, Gammaproteobacteria were initially more abundant but Betaproteobacteria predominated after phase IV. For Bacteroidetes, the community dynamics has also changed from phase IV onwards, with Flavobacteriia losing its high relative abundance to Saprospiria and Cytophagia. Several bacterial genera were detected throughout reactor operation, such as Phenylobacterium and Flavobacterium, while other were detected with higher abundance before (Methylocaldum and Plasticicumulans) or after phase IV (Thauera and Paracoccus). The relationship between bacterial community shifts and process performance was assessed. This study increases our knowledge on AGS technology application in real wastewater treatment.info:eu-repo/semantics/publishedVersio

Activity of nitrifying bacteria in aerobic granular sludge treating food industry wastewater

Aerobic Granular Sludge (AGS) is an innovative wastewater biological treatment, which uses less energy and space compared to other technological solutions. AGS presents a diverse microbial community responsible for the simultaneous removal of carbon and nutrients. These communities are protected by extracellular polymeric substances (EPS), which provide a compact structure to the granules. As a result, bacteria present in the aerobic granules are more resistant to variable wastewater composition, as commonly produced in food industry. In this study, carbon and NH4+ removal from a fish canning plant wastewater was evaluated using an AGS-SBR (sequential batch reactor), operated during 90 days. Chemical oxygen demand (COD) at the outlet was below the discharge limit of 125 mg O2 L-1 throughout the operation. Nitrification occurred during the first 23 days of operation. Between days 24 and 60, nitrification was completely inhibited, without ammonium removal from the wastewater. Nitrifying bacteria recovered their activity right after a decrease in the wastewater organic load, showing that the inhibition of the nitrification process was reversible. This study will contribute to our knowledge on the application of the AGS process to food industry wastewater treatment.N/

Aerobic granular sludge has EPS-producing bacteria able to tolerate salt

The aerobic granular sludge (AGS) process is a promising biotechnology which relies on the formation of compact biomass granules. Granulation occurs due to the overproduction of extracellular polymeric substances (EPS) by some microbes in response to stress conditions. EPS protect bacteria from the effect of toxic or inhibiting compounds present in the wastewater, such as salts. One of the current challenges is to use the AGS process to treat high salinity wastewater, commonly produced by agro-food and chemical industries. The main objective of this study was to screen for EPS-producing bacteria bacteria in an AGS reactor treating synthetic saline wastewater contaminated with a toxic compound. Several bacterial isolates were obtained from the reactor biomass. Genomic DNA was extracted and isolates (30) were grouped according to species similarity, based on RAPD profiles. Isolates displaying unique profiles (15) were subsequently identified by 16S rRNA gene sequencing analysis. Bacteria highly related to Pseudomonas, Aeromonas, Stenotrophomonas, Flavobacterium and Pseudoxanthomonas were obtained. Isolates SG4 (Stenotrophomonas) and FG10 (Flavobacterium) belong to bacterial genera associated to EPS production in granules. These were selected for growth and biofilm formation assays with increasing NaCl concentrations (0 to 35 g L-1). Both isolates were able to grow in the presence of 35 g NaCl L-1, despite at a lower growth rate. Although salt increase affected biofilm production, SG4 was the best biofilm producer. EPS production by SG4 in the presence of 10 and 20 g L-1 of NaCl was compared. EPS was extracted and the content in proteins, humic acids and carbohydrates was quantified. SG4 was able to produce more EPS in the presence of 10 g L-1 (123 mg g-1 VSS) compared to 20 g L-1 of NaCl (77.6 mg g-1 VSS). EPS-producing bacteria with ability to tolerate high salinity were retrieved from an AGS process treating synthetic wastewater. Further research is required to gain more knowledge on these bacteria and their importance for the robustness of a process treating saline wastewater.info:eu-repo/semantics/publishedVersio

Targeting aerobic granular sludge microbiome salt adaptation

Saline wastewaters can result from different economical activities, such as food and chemical industries. The need to overcome water shortage is also producing more saline wastewater, especially in coastal cities where seawater is used for cleaning processes. This is leading to the need of biological wastewater treatment technologies able to tolerate high salt concentrations. Aerobic granular sludge (AGS) has been appointed as the best aerobic treatment process for saline wastewater, mainly due to the high bacterial aggregation and self-protection level that granules offer. Due to the existence of different microbial metabolic layers within the granules, AGS technology is used for removing organic carbon as well as nitrogen and phosphorous from wastewater. In this study, AGS biomass was acclimated to saline wastewater, by performing a stepwise salt addition over a period of 250 days, from 0 to 14 g NaCl L-1. A high bacterial diversity existed while treating wastewater up to 3 g NaCl L-1. However, the salinity increase up to 6 g NaCl L-1 led to a relevant microbial diversity reduction. Salt increase led to the dominance of Proteobacteria, namely of Lysobacter and Rhodocyclus bacterial genera, both associated to carbon-nitrogen removal and EPS production in AGS processes, respectively. Despite this bacterial selection, carbon and nutrients removal processes were kept stable, even when salinity was increased to 14 g NaCl L-1, which was corroborated by the identification of bacteria responsible for such processes (e.g., PAO, AOB and NOB) throughout reactor operation. Hence, the AGS process was able to adapt to salt by preserving the metabolic diversity required for performing different biological removal processes, showing the microbial selection and plasticity occurring in AGS processes, an issue of great relevance for upgrading wastewater treatment.info:eu-repo/semantics/publishedVersio

Targeting aerobic granular sludge microbiome salt adaptation

Saline wastewaters can result from different economical activities, such as food and chemicals industries. The need to overcome water shortage is also producing more saline wastewater, especially in coastal cities where seawater is used for cleaning processes. This is leading to the need for biological wastewater treatment technologies able to tolerate high salt concentrations. Aerobic granular sludge (AGS) has been appointed as the best aerobic treatment process for saline wastewater, mainly due to the high bacterial aggregation and self-protection level that granules offer. Due to the existence of different microbial metabolic layers within the granules, AGS technology is used for removing organic carbon as well as nitrogen and phosphorous from wastewater. In this study, AGS biomass was acclimated to saline wastewater, by performing a stepwise salt addition over a period of 250 days, from 0 to 14 g NaCl L-1. A high bacterial diversity existed while treating wastewater up to 3 g NaCl L-1. However, the salinity increase up to 6 g NaCl L-1 led to a relevant microbial diversity reduction. Salt increase led to the dominance of Proteobacteria, namely of Lysobacter and Rhodocyclus bacterial genera, both associated to carbon-nitrogen removal and EPS production in AGS processes, respectively. Despite this bacterial selection, carbon and nutrients removal processes were kept stable, even when salinity was increased to 14 g NaCl L-1, which was corroborated by the identification of bacteria responsible for such processes (e.g., PAO, AOB and NOB) throughout reactor operation. Hence, the AGS process was able to adapt to salt by preserving the metabolic diversity required for performing different biological removal processes, showing the microbial selection and plasticity occurring in AGS processes, an issue of great relevance for upgrading wastewater treatment.info:eu-repo/semantics/publishedVersio