Abstract
The objective of achieving carbon neutrality by 2050 requires the various sectors of the economy to actively participate in the decarbonisation of all their activities, from production to consumption and product distribution. The vineyard and wine production sector is no exception to this goal. This paper aims to evaluate the feasibility and efficiency that hybrid energy systems based on renewable energy sources, solar photovoltaic (PV) and wind, can contribute to energy efficiency in certain activities related to wine production. In this sense, this study presents results based on linear programming optimisation models, which show how effective they are in minimising the use of energy from the power grid. The results show that renewable hybrid energy systems based on PV and wind are an effective solution for achieving carbon neutrality in some agricultural sectors, particularly winemaking sector. Besides being able to minimise the energy bought from the grid, the hybrid renewable energy system (HRES) is almost self-sufficient, being able to produce 340,232 kWh over 25 years.

Abstract
The sustainability of forest species is directly related to the success of stand regeneration. Assuring success is particularly critical in stands where perpetuity relies on natural regeneration, as is often the case with cork oak forests. However, 59% of the stand in Portugal have no natural regeneration, and climate change could further worsen the sustainability of the system. The study summarizes the factors that affect the natural regeneration of cork oak (Quercus suber L.) based on current knowledge and presents a case study on a forest in Northeast Portugal, where the natural regeneration of Quercus suber under the effect of climate change have been monitored and analyzed. The present work focuses on the effect of stand density, i.e., tree cover, on the production of acorns, the establishment and survival of seedlings, and the impact of the summer season on seedling mortality. The monitoring was carried out in February, June, September 2022, and January 2023 in two stands with distinct stand canopy cover, when the region was under extreme drought. Data analysis was performed using the analysis of variance for repeated measures and the Mann-Whitney-Wilcoxon test. The study showed that cork oak regeneration is influenced by stand density, which promoted the establishment success and survival of natural regeneration in a period of reduced precipitation, despite possible competition for water resources. The mean number of seedlings differed significantly between the two stands. However, there were no significant differences in the mean number of seedlings throughout the field measurements. Additionally, the percentage of dead seedlings was low even after the summer season (9.5% of the total seedlings) in the denser stand. These results indicate that high canopy cover can have a protective effect for extreme climatic events and should be considered in forestry management to promote regeneration of the cork oak forests.