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- Problemas de pragas em montado: o que sabemos e o que nos falta saberPublication . Branco, Manuela; Paulo, Joana Amaral; Sousa, Edmundo
- Carbon sequestration of modern Quercus suber L. silvoarable agroforestry systems in Portugal: a YeldSAFE-based estimationPublication . Palma, J.H.N.; Paulo, Joana Amaral; Tomé, MargaridaModern alley cropping designs, with trees aligned in rows and adapted to operating farming machinery, have been suggested for Europe. This paper explores the potential for adoption of cork oak (Quercus suber L.) agroforestry in Portugal and estimates the potential carbon sequestration. Spatial modeling and Portuguese datasets were used to estimate target areas where cork oak could grow on farmland. Different implementation scenarios were then modeled for this area assuming a modern silvoarable agroforestry system (113 trees ha-1 thinned at year 20 for establishing 50 trees ha-1). The YieldSAFE process-based model was used to predict the biomass and carbon yield of cork oak under low and high soil water holding capacity levels. Approximately 353,000 ha are available in Portugal for new cork oak alley cropping. Assuming implementation rates between 10 % of the area with low soil water capacity (60 mm: 15 cm depth, coarse texture) and 70 %of the areawith high soilwater holding capacity (1,228 mm: 200 cm depth, very fine texture), then carbon sequestration could be 5 9 106 and 123 9 106 Mg CO2 respectively. Due to higher yields on more productive land, scenarios of limited implementation in high productivity locations can sequester similar amounts of carbon as wide implementation on low productivity land, suggesting that a priori land classification assessments can improve the targeting of land and financial incentives for carbon sequestration
- Lessons learnt: montados in PortugalPublication . Faias, Sónia Pacheco; Firmino, Paulo; Tomé, Margarida; Palma, J.H.N.; Paulo, Joana AmaralThe AGFORWARD research project (January 2014 - December 2017), funded by the European Commission, is promoting agroforestry practices in Europe that will advance sustainable rural development. The project has four objectives: 1. to understand the context and extent of agroforestry in Europe, 2. to identify, develop and field-test innovations (through participatory research) to improve the benefits and viability of agroforestry systems in Europe, 3. to evaluate innovative agroforestry designs and practices at a field-, farm- and landscape scale, 4. to promote the wider adoption of appropriate agroforestry systems in Europe through policy development and dissemination. This report contributes to the second objective and Deliverable 2.5 which describes the lessons learnt from innovations within agroforestry systems of high natural and cultural value. Within the project, there were ten stakeholder groups focused on such systems (e.g. dehesas, montados, other wood pastures, and bocage). This report focuses on a trial established to understand the effect of understory management alternatives on the tree and cork growth, in pure cork oak woodlands, also commonly known in Portugal as ”Montado”
- Montado in Portugal. High natural and cultural value agroforestryPublication . Crous-Duran, Josep; Paulo, Joana Amaral; Palma, J.H.N.
- Carbon balance estimation for agroforestry land use alternatives in PortugalPublication . Crous-Duran, J.; Paulo, Joana Amaral; Palma, J.H.N.In 2005, 11% of the anthropogenic greenhouse gases emissions (GHG) were originated from agricultural activities and this value is expected to increase in the future. Besides the contribution for the restoration of soil productivity and for the improvement of conditions in degraded land, Agroforestry is also proposed as one of the main solutions for the mitigation of the GHG emissions and their effect on Climate Change. With European Union’s legislation supporting and promoting the conversion of land into low-carbon-integrated agriculture, new opportunities arise for the implementation of this type of land use in Europe. In Portugal, this type of agriculture is well represented by a traditional Agroforestry system called montado, combining low density cork oak trees (Quercus suber L) with pastoral activities occupying an area of 715,922 ha, with recent studies showing an extra area suitable for its implementation of around 353,000ha. Considering the new policies established by the EU in regard to the measures to be considered in agriculture for the Climate Change mitigation, and the capacity of the Agroforestry systems to act as a low-carbon and highly productive agriculture, two main objectives are proposed for this work: 1) Compare the potential capacity of the montado to mitigate the GHG emissions by quantifying the net carbon balance of activities in comparison to two other land-use alternatives occurring in the same area: dense cork oak forestry and wheat monoculture; 2) Quantify the benefits/consequences in terms of net carbon balance if new areas are converted into Agroforestry systems, as an alternative to current activities and management models. The methodology for the net carbon balance estimation includes the use of the Yield-SAFE model, calibrated for crop components and cork oak and current most used management practices concerning the three land use types and associated activities.
- O montado e a cortiça. Livro de ResumosPublication . Paulo, Joana Amaral; Pereira, Helena; Oliveira, Vanda
- A tree‑ and climate‑dependent growth model to predict mature annual cork thickness under different climate change scenariosPublication . Paulo, Joana Amaral; Firmino, Paulo N.; Tomé, MargaridaClimatic factors drive the annual growth of cork and the subsequent increase in its thickness, which, in addition to porosity, determines the price of cork. Therefore, the simulation of cork thickness is a crucial module of forest growth simulators for cork oak stands. As the existing cork growth models are independent of climatic factors, cork thickness under different climate change scenarios could not be simulated using these models. The primary objective of this study was to develop a climate-dependent tree model to predict annual cork growth. We also verified the hypothesis that the effects of climate change on cork annual growth are nonlinear, and vary with the cork age and thickness. Due to the limited amount of work developed around this topic, we evaluated three candidate models and selected the one that presented best prediction performance as the base model. A set of climate variables that characterized annual climatic conditions were tested in the base model parameters. The resulting climate-dependent model was referred to as the fixed-effects model, and used to initialize a mixed-effect model which accounted for the nested structure of the data. We considered two random effects—the plot and the trees inside the plot. Annual precipitation and the Lang index (ratio between annual precipitation and mean annual temperature) were the variables that showed best results when included in the model parameters. Using a ratio of the variable to cork thickness recorded during the previous year, in both cases, suggested a decline of the positive effect of annual precipitation and the Lang index for increasing cork thickness. The models developed in this study predicted the cork thickness of individual trees based on the cork age and under different climate change scenarios. Therefore, they can be used in forest growth simulators for forest management and research purposes.
- Using quantile regression to evaluate the impact of different factors in the cork caliper of cork oak trees in montado agroforestry ecosystemPublication . Paulo, Joana Amaral; Firmino, Paulo Neves; Faias, Sónia; Tomé, Margarida
- Impacto de diferentes alternativas de gestão na biomassa do subcoberto e no crescimento da árvore e da cortiçaPublication . Paulo, Joana Amaral; Faias, Sónia Pacheco; Firmino, Paulo; Tomé, Margarida
- Drivers for annual cork growth under two understory management alternatives on a podzolic cork oak standPublication . Faias, Sónia; Paulo, Joana Amaral; Firmino, Paulo N.; Tomé, MargaridaUnderstory management practices and stand density characteristics allow one to distinguish a cork oak traditional silvopastoral system (known as a montado) from a cork oak forest system. Although understanding the manner in which different management practices affect cork growth is imperative, there are still only a few outputs from experimental research that contribute to this knowledge. The effect of potential drivers on annual cork growth was analyzed using a linear mixed model approach. Two dimensions of drivers were considered: intraspecific competition, assessed by tree level distance-dependent indices; and interspecific competition, assessed by variables characterizing understory management. The present dataset was collected from an experimental trial established on a cork oak stand in Podzolic soil on the Tagus river basin, covering two different cork growth cycles over the period from 2003 to 2015. The adjusted models considered two understory management alternatives: spontaneous shrubs maintenance and forage application. In both models, annual precipitation displayed a positive effect on annual cork growth, as expected. However, no significant effect of intraspecific competition was found. Additionally, there was a positive effect on annual cork growth associated with the spontaneous shrubs growth and a negative effect associated with lupine presence; both effects linked to different cork ring ages’ thresholds. The study main contributions are the following: (i) the introduction of the interaction between cork growth cycle stage and understory management practices, only possible with cork sample collections from different cork rotation cycles; (ii) the finding that there was no significant effect of intraspecific competition on cork growth