Browsing by Author "Esteves, Catarina"
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- Assessing the contribution of ECa and NDVI in the delineation of management zones in a vineyardPublication . Esteves, Catarina; Fangueiro, David; Braga, Ricardo; Martins, Miguel; Botelho, ManuelPrecision fertilization implies the need to identify the variability of soil fertility, which is costly and time-consuming. Remotely measured data can be a solution. Using this strategy, a study was conducted, in a vineyard, to delineate different management zones using two indicators: apparent soil electrical conductivity (ECa) and normalized difference vegetation index (NDVI). To understand the contribution of each indicator, three scenarios were used for zone definition: (1) using only NDVI, (2) only ECa, or (3) using a combination of the two. Then the differences in soil fertility between these zones were assessed using simple statistical methods. The results indicate that the most beneficial strategy is the combined use of the two indicators, as it allowed the definition of three distinct zones regarding important soil variables and crop nutrients, such as soil total nitrogen, Mg2+ cation, exchange acidity, and effective cation exchange capacity, and some relevant cation ratios. This strategy also allowed the identification of an ionic unbalance in the soil chemistry, due to an excess of Mg2+, that was harming crop health, as reported by NDVI. This also impacted ECa and NDVI relationship, which was negative in this study. Overall, the results demonstrate the advantages of using remotely sensed data, mainly more than one type of sensing data, and suggest a high potential for differential crop fertilization and soil management in the study area
- Development of the HIV360 international core set of outcome measures for adults living with HIV: a consensus processPublication . Marques‐Gomes, João; Salt, Matthew J.; Pereira‐Neto, Rita; Barteldes, Franca S.; Gouveia‐Barros, Vera; Carvalho, Alexandre; d’Arminio‐Monforte, Antonella; De‐la‐Torre‐Rosas, Alethse; Harris, Amy; Esteves, Catarina; Maor, Carcom; Mora, Cristina; Oliveira, Carla; Sousa, Cristina; Richman, Douglas D.; Martinez, Esteban; Medeiros, Fábio; Gramacho, Filipa; Behrens, Georg M. N.; Gonçalves, Graça; Farinha, Helena; Nabais, Isabel; Vaz‐Pinto, Inês; Sierra‐Madero, Juan; Sousa‐Gago, Joaquim; Thornhill, John; Vera, José; Erceg‐Tusek, Maja; Tavares, Margarida; Vasconcelos, Miguel; Fernandes, Nuno; Gianotti, Nicola; Langebeek, Nienke; Anjos, Paulo; Couto, Raquel; Fernandes, Ricardo; Rajasuriar, Reena; Serrão, Rosário; Watson, Shaun; Branco, Teresa; Teixeira, Tiago; Soriano, VicenteObjectives: HIV outcomes centre primarily around clinical markers with limited focus on patient-reported outcomes. With a global trend towards capturing the outcomes that matter most to patients, there is agreement that standardizing the definition of value in HIV care is key to their incorporation. This study aims to address the lack of routine, standardized data in HIV care. Methods: An international working group (WG) of 37 experts and patients, and a steering group (SG) of 18 experts were convened from 14 countries. The project team (PT) identified outcomes by conducting a literature review, screening 1979 articles and reviewing the full texts of 547 of these articles. Semi-structured interviews and advisory groups were performed with the WG, SG and people living with HIV to add to the list of potentially relevant outcomes. The WG voted via a modified Delphi process - informed by six Zoom calls - to establish a core set of outcomes for use in clinical practice. Results: From 156 identified outcomes, consensus was reached to include three patient-reported outcomes, four clinician-reported measures and one administratively reported outcome; standardized measures were included. The WG also reached agreement to measure 22 risk-adjustment variables. This outcome set can be applied to any person living with HIV aged > 18 years. Conclusions: Adoption of the HIV360 outcome set will enable healthcare providers to record, compare and integrate standardized metrics across treatment sites to drive quality improvement in HIV care.
- Partial replacement of chemical fertilizers with animal manures in an apple orchard: Effects on crop performance and soil fertilityPublication . Esteves, Catarina; Fangueiro, David; Mota, Mariana; Martins, Miguel; Braga, Ricardo P.The combined use of chemical fertilisers with organic materials in crop fertilization is an essential approach to transition towards a more sustainable and resilient agriculture in Europe. In an apple orchard, chemical fertilisers (CF) were partially (25 to 57%) replaced with animal manure (cattle slurry - CS, acidified cattle slurry - ACS, cattle solid manure - CsM, and poultry manure - PM), based on the crop’s nitrogen (N) requirements. Apple production and soil properties were monitored during a 3-year experiment. At the end of the third year, leaf N was higher in the control treatment (CTRL, 100% CF). Apple production was, on average, higher in the CS treatment, although not significantly different from the CTRL. Fruit analysis showed that replacing CF with animal manures did not significantly impacted fruit quality (weight, ºBrix and firmness). Soil organic carbon (SOC), N and exchangeable potassium (K+) were significantly higher in the manure treatments. The increase in soil K+ in the manure treatments consequently increased soil K/magnesium (Mg) ratio, slightly mitigating K and Mg antagonism, as seen by the increase in fruit K. However, K content was still deficient in fruits and leaves in all treatments. It can be concluded that the partial replacement of chemical fertilisers by animal manures (CS, ACS and PM) had a positive effect on soil health with no decrease of apple production.
- Partial replacement of mineral fertilisers with animal manures in an apple orchard: Effects on GHG emissionPublication . Esteves, Catarina; Costa, Eva; Mata, Miguel; Mota, Mariana; Ribeiro, Henrique; Fangueiro, DavidPartial replacement of mineral fertilisers (MF) with animal manures is a good alternative to reduce MF use and increase both nutrient cycling in agriculture and soil organic matter. However, the adoption of this practice must not lead to increased environmental impacts. In this two-year study conducted in an apple orchard, MF were partially replaced with various animal manures, including cattle slurry (CS), acidified cattle slurry (ACS), solid cattle manure (CsM), or poultry manure (PM), and their impacts on greenhouse gas emission (GHG: CO2, N2O and CH4) were examined. A control (CTRL) receiving only MF served as the baseline, representing the con- ventional scenario in orchard fertilisation. Overall, replacing MF with manures increased GHG emissions, with the magnitude of the impacts depending on the specific characteristics of the manures and the amount of nu- trients and organic matter applied. Comparing to the CTRL, application of ACS and CS led to higher CH4 and N2O emissions, while PM application increased both N2O and CO2 emissions. In contrast, replacement with PM and CsM decreased CH4 emissions. Nevertheless, results varied between the two years, influenced by several factors, including soil conditions. While acidification showed potential to mitigate CH4 emissions, it also led to increased N2O emissions compared to CS, particularly in 2022, suggesting the need for further investigation to avoid emission trade-offs. Replacement with CS (20.49 t CO2-eq ha 1) and CsM (20.30 t CO2-eq ha 1) showed com- parable global warming potential (GWP) to the conventional scenario (CTRL, 19.49 t CO2-eq ha 1), highlighting their potential as viable MF substitutes
- Projecto Nutri2cycle: soluções para a circularidade de nutrientes e carbono na EuropaPublication . Alvarenga, Paula; Prado, Joana; Esteves, Catarina; Silva, Arejacy; Fangueiro, DavidO projeto Nutri2Cycle (Horizonte 2020), tem como principal objetivo desenvolver os mecanismos que permitam uma circularidade mais eficiente de carbono e nutrientes (principalmente N e P), entre o setor agrícola e a produção animal, levando ao desenvolvimento de uma agricultura mais sustentável nos diferentes sistemas agrícolas Europeus. Neste sentido, é vital o contributo tecnológico do processamento, que permitirá tornar mais eficaz a valorização dos nutrientes existentes nos efluentes pecuários e agro-resíduos. Alguns parceiros têm instaladas unidades de demonstração a várias escalas (piloto, campo e comercial), com abordagens integradas e inovadoras de gestão de nutrientes, a fim de avaliar a viabilidade técnica dessas soluções e de favorecer a sua transferibilidade entre regiões da União Europeia. Passam por soluções para as explorações pecuárias, com vista à otimização da gestão de nutrientes e à redução da emissão de gases de efeito de estufa; pelo tratamento de efluentes agropecuários com produção de biomassa enriquecida em proteínas para uso na alimentação animal; pela produção de fertilizantes de base biológica, obtidos por tratamento dos efluentes pecuários; pela demonstração da substituição de fertilizantes químicos por efluentes pecuários, ou produtos do seu processamento, em diferentes sistemas agrícolas; e também, pela apresentação de soluções tecnológicas para uma fertilização de precisão. É sobre o projeto Nutri2Cycle e estas unidades que de demonstração que se debruça este artigo.
- Remote Sensing (NDVI) and Apparent Soil Electrical Conductivity (ECap) to Delineate Different Zones in a VineyardPublication . Esteves, Catarina; Ribeiro, Henrique; Braga, Ricardo; Fangueiro, DavidThe intensification of agriculture has greatly enhanced crop productivity, but also its potential environmental impact. Nutrient recycling and an increase in resource use efficiency are the key points to keep production at high levels with minimum impact. The present work’s goal was to provide new insight on the spatial variability of soil chemical properties in a vineyard. For this, three different zones were identified in a 6.77 ha parcel, according to the remote sensing of apparent soil electrical conductivity (ECap) and the normalized difference vegetation index (NDVI). Soil samples from specific locations were then collected and chemically described, and the resulting data were statistically analyzed. ECap and NDVI appeared to be efficient tools to define different zones within the vineyard, with most of the soil chemical properties varying at the highest significance level (p < 0.001) according to the F test, except for extractable phosphorus (Égner-Rhiem) and organic carbon (TOC method). Overall, our results revealed potential for the implementation of site-specific soil fertilization and soil quality management