Percorrer por autor "Calheiros, Cristina"
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- Aromatic plants for water treatment in Green roofs technologyPublication . Monteiro, Cristina M.; Calheiros, Cristina; Castro P. M. L, Paula M. L
- Aromatic plants for water treatment in green roofs technologyPublication . Monteiro, Cristina M.; Calheiros, Cristina; Castro, Paula M. L.
- Assessment of culturable endophytic community of Canna flaccida plants growing in a constructed wetlandPublication . Calheiros, Cristina; Pereira, Sofia; Castro, Paula M. L.Sustainable water management urges for the treatment of wastewater in an efficient way. With the latter purpose, ecotechnologies arise as promising solutions for rural and mountain areas lacking a sewage network. Constructed wetlands (CW) coupled with preliminary/primary systems foresee enhancement of the water quality and its possible reuse. The challenge presented in this work reflects the application of a CW to domestic wastewater treatment coming from a tourism house, situated in a rural area. The use of different ornamental plants species to treat the wastewater was an important component of the system, increasing biodiversity and supporting the local ecosystem. Performance of the CW was assessed in terms of physic-chemical and microbial parameters. The endophytic culturable bacteria of a selected plant species, Canna flaccida, were evaluated.
- Assessment of trombidiidae (acari) as biondicators for wasterwater treatment in a constructed wetlandPublication . Magalhães, João Pedro Correia de Sousa; Pereira, Sofia I. A.; Leong, Chi Man; Xu, John Hongxi; Calheiros, CristinaThe family Trombidiidae (subclass Acari), commonly known as red velvet mites, exhibits dietary habit shifts throughout their development. Larvae are parasitic, while nymphs and adults transition to a free - living, soil - dwelling predator stage. Predation by these mites is usually done in rocks, tree stumps, plants, leaf litter, and moss, with other arthropods and their eggs being their prey. These hunting environments fit the habitat created by constructed wetlands (CWs) biological wastewater treatment systems, mimicking the processes and conditions that occur in natural wetlands. Trombidiidae are recognized for their potential as bioindicators due to their sensitivity to a range of environmental factors. The presence of Trombidiidae was confirmed in all seasons in a 15-year - old CW located at a rural tourism house, implying that this CW maintains favorable environmental conditions year round. The simultaneous occurrence of spiders within the same system indicates that their life cycle is likely sustained within this system. As both parasites and predators of the biodiversity presented in the CW, Trombidiidae may contribute to a deeper understanding of the food web within these systems, and provide proof as bioindicators of the ecological and habitat benefits CWs can provide. This work involved seasonal sampling of macrofauna at multiple collection spots within and around the CW, complemented by substrate core sampling to assess belowground communities. The collected specimens were sorted, identified, and quantified, with statistical analysis currently underway. Preliminary results indicate a robust and well - structured ecosystem, with the consistent presence of Trombidiidae across all seasons, suggesting a stable population.
- Biocenoses de eucariotas em leitos de plantas para tratamento de águas residuaisPublication . Sepúlveda, Goreti; Mina, Isabel A. P; Calheiros, Cristina; Castro, Paula M. L.Os Leitos de Plantas ou Leitos de Macrófitas constituem o tratamento secundário de água residual, dos sistemas de baixa tecnologia conhecidos por FitoETARs. Em casos concretos, as FitoETARs apresentam vantagens relevantes em relação aos sistemas de tratamento de águas residuais mais conhecidos. Com vista ao estudo das biocenoses rizosféricas de uma FitoETAR localizada na Unidade de Turismo de Habitação do Paço de Calheiros (concelho de Ponte de Lima), análises microbiológicas de amostras de água e análises microscópicas de amostras de substrato e raízes do leito foram acompanhadas pela monitorização de parâmetros físico-químicos e bioquímicos, tais como temperatura, pH, Carência Bioquímica de Oxigénio (CBO5) e Carência Química de Oxigénio (CQO). A eficiência de remoção da CBO5 e da CQO foi em média de 96% e 92%, respetivamente. Nas amostras analisadas ao microscópio observaram-se alguns metazoários e foram identificados 20 taxa de protozoários, 15 dos quais ciliados. Foi também constatada uma certa variação espacial e temporal da densidade e diversidade dos eucariotas. Sendo já reconhecido o importante papel dos diferentes grupos funcionais de protozoários nos sistemas de lamas ativadas onde são utilizados como bioindicadores, a sua monitorização em FitoETARs adivinha-se muito vantajosa.
- Bioinocula application in maize plants growing in a P-deficient agricultural soilPublication . Pereira, Sofia; Calheiros, Cristina; Castro, Paula M. L.Introduction: According to the United Nations predictions, the human population will reach 9 billion people by 2050, being imperative an increase in food supply. Phosphorus (P) is a limiting factor in crop growth and, due to its low availability, P-deficiency in soils is widespread, and as such the successive application of P-fertilizers to maintain crop production has occurred (Sharma et al., 2013), leading to severe environmental problems. Microbial mediated P management appears as an eco-friendly tool for agricultural sustainable practices. The harnessing of Phosphate Solubilizing Bacteria (PSB) seems to be of utmost importance towards the reverse of the current use of large amounts of P fertilizers, since they can stimulate plant growth in particular through the conversion of bound P in soil into bioavailable P forms (Pereira and Castro, 2014). This work aimed to evaluate the ability of phosphate-solubilizing bacteria (PSB) to enhance Zea mays growth in an agricultural P-deficient soil. Strains were screened for their ability to solubilize P and to produce plant growth promoting (PGP) substances. The best P- solubilizing strains Rhodococcus sp EC35 (B1), Pseudomonas sp. EAV (B2) and Arthrobacter nicotinovorans EAPAA (B3) were inoculated in maize plants growing in P- deficient soils without P fertilization and amended with soluble (KH2PO4) and with tricalcium phosphate (TCP). Methods: The ability of bacterial isolates to solubilize phosphate was performed in liquid culture using National Botanical Research Institute's phosphate growth medium (NBRIP) supplemented with 5 g l-1 of TCP. Strains were sampled at different time intervals (0, 1, 2, 3, 6, 8 and 10 days) for determining soluble phosphate, pH and acid phosphatase. Bacterial strains, Rhodococcus sp. EC35; Pseudomonas sp. EAV and A. nicotinovorans EAPAA, were used for exploring their potential to improve Z. mays growth in P-deficient soils. Greenhouse experiment consisted of a factorial design with three phosphate treatments: control – without P fertilization, soluble P (KH2PO4) and TCP (sparingly soluble P) and 5 types of inoculation: no bacteria – B0 (uninoculated control), B1 (Rhodococcus sp. EC35), B2 (Pseudomonas sp. EAV), B3 (A. nicotinovorans EAPAA) and BM – (mixture of B1, B2 and B3). After 90 days plants root elongation, shoot height and plant dry biomass were determined. Total P in the roots and shoots and available P in rhizosphere soils were determined at the end of experiment. The persistence of inoculated strains in soils was evaluated by Denaturing Gel Gradient Electrophoresis (DGGE). Results and discussion: The PSB decreased pH of the growth medium and simultaneously increased soluble P when grown in liquid culture. The negative relationship observed suggested that acidification of the medium could facilitate P solubilization. In soils amended with TCP, the bacterial strain that better performed was A. nicotinovorans EAPAA (B3) which increased root biomass by 81% and root P concentration by 8.6%. Mixed inoculation (BM), also promoted root biomass production by 83% and P uptake by 2.6%. These results clearly indicated that inoculation with strains B3 and with BM is closely related to a better absorption of P from soil. Bacterial inoculation also improved Z. mays biomass and P root and shoot accumulation in soils without P fertilization, despite the initial low levels of available P in soils. The results obtained by DGGE showed that rhizobacteria were able to colonize rhizosphere soils of the Z. mays plants and were detectable after 45 days in all treatments. Taking into consideration that maize need a higher P supply in the initial stages of development, the persistence of bacterial strains in rhizosphere soils at least up to 45 days (half the life cycle of the plant) showed that these PSB can be used as bioinoculants and significantly promote growth of Z. mays in P-deficient soils, especially in early stages of maize growth. Conclusions: Inoculation of Z. mays plants with selected rhizobacteria significantly enhanced plant growth and nutrition in P-deficient soils. Strains Rhodococcus sp. EC34, Pseudomonas sp. EAV and A. nicotinovorans EAPAA may be used as biofertilizers in order to improve maize growth in P-deficient soils, constituting an interesting alternative to the application of P fertilizers, reducing costs and improving crop yields.
- Constructed wetland: multi-functional benefits of an ecological engineered systemPublication . Ojediran, Adetunji; Pereira, Sofia Almeida; Rosa-Santos, Paulo; Rodrigues, Ana Cristina; Calheiros, CristinaIntroduction: Constructed wetlands (CWs) are engineered systems that are inspired by natural wetlands [1]. They are often applied for decentralized wastewater treatment, but while their performance in pollutant removal is well established, other potential ecosystem services are often underappreciated. This study aims to bring attention to the broader multifunctional benefits of CWs —beyond treatment —by exploring a real - scale horizontal subsurface flow CW (HSSF - CW) located at a tourism facility in northern Portugal. Method: The CW, in operation since 2010, serves a rural guesthouse in Calheiros and consistently treats domestic wastewater generated from the guesthouse’s occupancy of between 6 and 40 people. The system covers an area of 40.5 m² and is vegetated with a polyculture of ornamental species, which is primarily for wastewater treatment at the facility but has also served aesthetic purposes. The CW operates under Mediterranean climatic conditions and discharges into a small polishing pond. Previous studies at this site have focused on pathogen removal and microbial communities [2], [3]. The current investigation builds on this foundation by identifying and evaluating other potential ecosystem functions. Results: The system’s stable operation provides a unique opportunity to assess additional services such as carbon sequestration (using biomass and substrate), energy recovery (from microbial fuel cell), soil amendments (biomass composting), safe water reuse for irrigation, and possibility of enhanced wastewater treatment (using photocatalytic modules and nanostructured filters). These aspects are now being explored to better understand the full value of CWs in multifunctional, real -world contexts. Conclusion: Recognizing the broader ecosystem functions of CWs is essential to reposition them as more than just wastewater treatment technologies. This study uses a successful, long - running HSSF - CW as a platform to investigate underexplored multifunctional benefits to show CWs's role as valuable ecosystem infrastructure —especially in decentralized settings like tourism where aesthetics, sustainability, and recovery of resources are essential.
- Contributions to the improvement of green roofs in Mediterranean climate, including rainwater harvestingPublication . Monteiro, Cristina; Calheiros, Cristina; Pimentel-Rodrigues, Carla; Silva-Afonso, Armando; Castro, Paula M. L.Green roofs (a type of construction that uses vegetation on the top of buildings) present the opportunity to contribute to the ecological sustainability of the urban environment in many ways, such as favouring the thermal performance of buildings and increasing humidity and contributing to CO2 sequestration in cities. On the other hand, rainwater harvesting is also important in urban areas, not only as a contribution for the global sustainability of buildings, through the increase of their water efficiency, but also to reduce flood peaks on public stormwater drainage systems. Green roofs and rainwater harvesting systems are technologies already known in the world, but for which there are a wide possibility of development and improvement, especially with regard to their adaptation to regional climates, such as the Mediterranean one. These technologies are particularly important in the Mediterranean basin, at risk of high water stress, and must be combined properly in view of the climate specificity. This paper describes the studies in this area conducted by Portuguese Catholic University/College of Biotechnology, in collaboration with ANQIP, a Portuguese Civil Society Association working on water efficiency in buildings, in terms of substrates, runoff coefficients and water quality collected in a pilot green roof. This study seeks to improve the basis for the design of rainwater harvesting systems in buildings with green roofs and a new expression is proposed for calculating monthly runoff coefficients under Mediterranean climate in extensive green roofs.
- Contributos para a adoção dos telhados verdes como tecnologia de retenção e aproveitamento de águas pluviaisPublication . Monteiro, Cristina; Calheiros, Cristina; Pimentel-Rodrigues, Carla; Silva-Afonso, Armando; Castro, Paula M. L.Os telhados verdes são uma solução arquitetónica que consiste na aplicação de substrato e vegetação sobre a cobertura impermeável de um edifício. A sua aplicação tem vindo a aumentar nos últimos anos, pelo facto de apresentar inúmeras vantagens, nomeadamente melhoria da qualidade do ar em áreas urbanas, promoção de ecossistemas nas cidades, redução do efeito “ilha de calor” e melhoria da eficiência tanto energética como acústica dos edifícios. Os telhados verdes reduzem também os caudais de ponta na drenagem pluvial, contribuindo para amortecer os picos de cheia em ambiente urbano, e são uma solução promissora para a melhoria da qualidade da água de escoamento, visando um posterior aproveitamento. Neste trabalho, desenvolveu-se um telhado verde experimental utilizando plantas aromáticas autóctones, com o objetivo de avaliar a qualidade da água da chuva após passagem por um substrato selecionado, bem como caracterizar o ciclo da água (escoamento, retenção, etc.) de forma a fornecer contributos para a expansão da aplicação deste tipo de tecnologias conjuntamente para o aproveitamento de águas pluviais em edifícios. Os principais resultados obtidos permitiram o desenvolvimento de um modelo referente à determinação do coeficiente de escoamento, bem como a caracterização da qualidade da água na perspetiva de posterior reutilização.
- Floating wetland islands as a water treatment technologyPublication . Pereira, Sofia; Calheiros, CristinaFloating wetland islands (FWIs) are innovative nature-based solutions designed to enhance water quality in various aquatic environments, including lakes, ponds, and reservoirs, while restoring their ecological functions. In recent years, FWIs have gained popularity due to their effectiveness, low cost, and low maintenance needs. These systems provide a range of valuable ecosystem services, such as boosting biodiversity, enhancing aesthetic appeal, and improving water quality through phytoremediation. The plants on FWIs absorb excess nutrients like nitrogen and phosphorus, mitigating nutrient pollution, reducing eutrophication, and preventing water body degradation. Additionally, the microorganisms associated with plant roots and floating mats decompose organic matter, while the plants facilitate oxygen transfer into the water. Moreover, FWIs provide essential habitats for wildlife such as birds and insects, thereby enriching local biodiversity. This study aimed to showcase the implementation of an FWI composed of a polyculture of Iris germanica, Acorus gramineus, Caltha palustris, and Typha latifolia, established on a cork agglomerate platform in a freshwater pond. The FWI was installed in 2018, with ongoing monitoring to evaluate improvements in local biodiversity and to assess the long-term effectiveness of the buoyancy in supporting plant growth.