Percorrer por autor "Moreira, Olga"
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- Cattle effluents, either composted or bio-digested by Black Soldier Fly larvae, in the fertilization of ryegrass in sandy soilsPublication . Menino, Regina; Lopes, Ivã; Semedo, José N.; Scotti-Campos, Paula; Murta, Daniel; Castelo-Branco, Amélia; Nestler, Cecília; Moreira, OlgaThe relative agronomic performance of two organic fertilizers - effluents from intensive cattle farming, after composting either by traditional aerobic methods (compost) or by bio-digestion by larvae of the black soldier fly (Hermetia illucens, BSF) (frass) - in the growth of annual ryegrass (Lolium multiflorum L.) on a sandy soil was evaluated. For this purpose, a pot trial was conducted in a semi-controlled greenhouse. Eight treatments were defined, with four treatments using the compost and four treatments using frass (with a 10% nitroamoniacal nitrogen supplementation in all treatments), in addition to a negative control without fertilization, and a positive control with exclusively chemical nitroamoniacal fertilization. Regarding the biomass production, the BSF frass displayed a higher potential than the compost, with a significantly higher production from an N endowment equivalent to 280 kg ha-1 (252 kg organic N + 28 kg mineral N). While the yields obtained with compost were stable when 350 kg ha-1 (315 kg organic N + 35 kg mineral N) were provided, the yields obtained with BSF frass revealed a tendency to continue to progress with higher doses. This could be justified by the fact that the P2O5 and K2O content of BSF frass is significantly higher than that of the compost, and these nutrients continued to be mineralized over time. Furthermore, the obtained results confirm the potentiating effect of mineral fertilizers in the maximization of biomass production, when associated with organic fertilizers in adequate proportions. In addition, it was verified that the addition of frass enhanced the water use by plants, which was significantly higher than the treatments with compost, regardless of the N endowment. It was concluded that mixing chemical and organic fertilizers positively impacts soil fertility and the sustainability of the production as a whole, by increasing productivities in a sustainable way.
- A comprehensive ecotoxicological evaluation of a treated olive mill wastewater and obtained sludgePublication . Pinto, José N.; Pereira, Andreia; Silva, Ana Rita. R.; Cardoso, Diogo N.; Mostafaie, Amid; Campos, Fábio; Rehan, Iryna; Moreira, Olga; Lopes, Ivã Guidini; Murta, Daniel; Afonso, Alexandra; Oliveira, Margarida; Silvério, Karina S.; Santos, Maria Teresa; Carvalho, Fátima; Almeida, Adelaide; Loureiro, SusanaOlive mill wastewaters (OMWWs) are an environmental problem in the Mediterranean region, and it is crucial to explore strategies for their treatment and repurposing. The chemical precipitation technique (CPT) has been presented as a cost-effective wastewater treatment solution that might be applied to OMWW. The CPT-resulting precipitant subproducts (sludge) may be reprocessed (e.g., agricultural fertilizer and/or soil amendment), while the treated wastewater may be repurposed or reused (e.g., irrigation, aquaponic, or industrial processes). This study aimed to evaluate the efficacy of CPT in treating wastewater from the olive oil industry from an ecotoxicological perspective. Additionally, to assess the safe use of the obtained sludge in CPT treatment, its effects on soil biota were assessed. For this, a set of ecotoxicological assays using freshwater (Raphidocelis subcapitata, Daphnia magna and Danio rerio), terrestrial invertebrates (Folsomia candida and Enchytraeus crypticus), and plants (Brassica oleracea and Lolium perenne) were used as model organisms. Results demonstrated that CPT reduced OMWW toxicity to freshwater organisms, offering a favorable outlook on CPT’s potential as a wastewater treatment method. Increasing application rates of sludge in soil reduced the shoot biomass and the hydric content of both plants compared to the control. Survival of F. candida and E. crypticus was not affected by sludge in soil at any tested application rate, yet sludge application negatively affected the reproduction of both species, even at relevant sludge application rates (2%) of sludge in soils. Overall, the applicability of this sludge obtained by the CPT treatment in soils should be carefully evaluated due to the observed adverse effects on soil biota. Although the results of CPT were promising in reducing the toxicity of OMWW for these aquatic species, some adjustments/improvements should be performed to improve this technique and use all the obtained resources (treated water and sludge) in a fully circular perspective.
- Effects of defatted black soldier fly (Hermetia illucens) meal on the performance, digestibility and blood parameters of weaned pigletsPublication . Parreiras, Mara; Pinheiro, Victor; Moreira, Olga; Soares, Maria; Murta, Daniel; Barros, Ana Novo; Outor-Monteiro, DivanildoThis study investigated the effects of different inclusion levels of defatted black soldier fly (Hermetia illucens: BSF) larval meal on growth performance, haematological and biochemical blood parameters, and nutrient digestibility in piglets. Forty-eight male piglets weaned at 28 days of age ((Landrace × Large White) × (Piétrain)) were randomly assigned to three experimental treatments. Each treatment included eight pens with two piglets per pen. Diets were formulated to be isoenergetic and isoproteic, containing defatted BSF meal as a partial replacement for fishmeal and soybean meal: Control (0% BSF), BSF3% (3% inclusion), and BSF6% (6% inclusion). Over the whole experimental period, dietary treatment did not significantly affect final body weight, average daily gain, average daily feed intake, or feed conversion ratio, although feed intake differed during the 7–28-day period. Red and white blood cell parameters were not influenced by diet. Apparent total tract digestibility of dry matter and organic matter increased at the 6% inclusion level, while crude protein and crude fat digestibility were not affected. These results indicate that defatted BSF meal can be used as a sustainable alternative protein source in piglet diets, maintaining growth performance and health status.
- Hermetia illucens L. frass in promoting soil fertility in farming systemsPublication . Menino, Regina; Esteves, Catarina; Fareleira, Paula; Mano, Raquel; Antunes, Joana; Rehan, Iryna; Murta, Daniel; Moreira, OlgaFollowing a pot trial with annual ryegrass (Lollium multiflorum Lam. (Pooideae: Poaceae)), where the effect of chemical fertilization was compared with organic fertilization with Black Soldier Fly larvae frass (BSFF), obtained by bio-digestion of cattle production effluents, and with mixed fertilization in proportions of 25%, 50%, and 75% of BSFF, the effect on crop production and soil fertility was tested in three soils of different textures, namely, sandy soil (Gleyic podzol), calcareous soil (Haplic calcisol), and clay soil (Haplic fluvisol). On top of the previous experimental device, a second year of testing was carried out with sowing of the same crop, but without any fertilizer input in all the residual soils for the different further modalities. With regard to the second sowing cycle production, the results are supportive of the expectation that fertilization with BSFF has a superior capacity for soil fertility resilience (assessed in terms of the ability to maintain or even increase soil production in the following year, in the absence of any fertilizer application) in all the soils tested in this experiment, with a significantly greater difference in the treatment corresponding to fertilization with only BSFF compared to the exclusively chemical treatment, in all the soils tested. Furthermore, BSFF, preferably as a mixed fertilizer (in a proportion until 75%), is shown to be a promising alternative for Gleyic podzol in the production of ryegrass as in the resilience and promotion of soil productivity. As far as more fertile soils are concerned (as in the case of Haplic calcisol and Haplic fluvisol), BSFF has not proved promising in terms of immediate crop production.