Repositório do LNEG
Repositório Científico do Laboratório Nacional de Energia e Geologia
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Portuguese historical palaeobotanical collections reveal a new species of late Palaeozoic marattialean fern
Publication . Correia, Pedro; Šimunek, Zbynek; Pereira, Zélia
ABSTRACT: A new Late Pennsylvanian marattialean species, Cyathocarpus felicianoi sp. nov., is described and illustrated from the Douro Carboniferous Basin, northwestern Portugal, from Stephanian C (upper Gzhelian, Upper Pennsylvanian) deposits. The studied fossil material is composed of penultimate and ultimate sterile ‘pecopterid’ frond fragments preserved as adpressions and belongs to the Carlos Teixeira's collection, an invaluable palaeobotanical collection from the Portuguese geological surveys. The description of this new fern fossil-species based on historical palaeobotanical collections, highlights the importance of natural history collections for the advancement of science, especially regarding the knowledge about diversity and richness of marattialean ferns of Euramerican Carboniferous.
Microalgae-Based Treatment of Winery Wastewater
Publication . Lopes da Silva, Teresa; Lopes, Tiago; Reis, Alberto
ABSTRACT: Winery wastewater (WWW) is a high-strength effluent characterized by high organic load, nutrient content, and seasonal variability, posing significant environmental challenges. This review critically evaluates microalgae-based systems for WWW treatment, addressing their performance, scalability, and role within circular bioeconomy frameworks. Analysis of recent studies shows that microalgae-based systems can achieve high pollutant removal efficiencies, including up to ~ 90–92% chemical oxygen demand removal, high removal of total organic carbon and nitrogen (typically above 80%), and up to 91–95% ammonium removal. These systems also enable the production of biomass rich in proteins (up to ~ 58.8% dry weight) and valuable compounds such as pigments, supporting multiple valorization pathways. A key finding is that, despite strong technical performance, large-scale implementation remains limited. The main constraints are associated with wastewater variability, presence of inhibitory compounds, and operational challenges in biomass recovery, particularly energy-intensive harvesting and downstream processing. Techno-economic and life cycle analyses indicate that standalone systems are rarely economically viable under current conditions, and that feasibility depends on integration into multiproduct biorefineries and existing infrastructures. Regulatory uncertainty and the need for stakeholder acceptance further constrain deployment. Overall, microalgae-based WWW treatment represents a promising but system-dependent solution, requiring integrated technological, economic, and policy frameworks to achieve scalable implementation.
Land use planning and safeguarding of mineral resources: the case of Portugal
Publication . Carvalho, Jorge; Lisboa, Jose; Salgueiro, Rute
ABSTRACT: An analysis of the Portuguese spatial planning policy framework and a sample of municipal master plans reveals that mineral resources are addressed within the context of extractive activities, not as natural resources worthy of safeguarding for extraction when society needs them. The approach to mineral safeguarding involves delimiting areas for the exploitation of geological resources on zoning maps and ensuring the compatibility of uses between agricultural and forestry areas with mineral extraction activities. However, practice shows that this is not adhered to in most master plans, allowing to conclude that the current legislative framework and practice severely restrict access to mineral resources.
Geochemical and Sr-Nd isotope constraints on the provenance of Permian deposits from Mozambique's Lower Karoo Zambezi Basin
Publication . Jorge, Raul C. G. Santos; Fernandes, Paulo; Pereira, Zélia; Santos, José Francisco; Lopes, Gilda; Marques, João
ABSTRACT: Whole-rock geochemistry and Sr-Nd isotopic compositions of Permian mudrocks from the Moatize and Matinde formations were analysed to constrain the sediment provenance, weathering history and palaeogeographic setting of the Moatize - Minjova Sub-Basin in the Karoo Zambezi Basin of Mozambique. The geochemical signatures of both formations suggest minimal effects of recycling and sorting, and point to rapid sediment deposition within an active tectonic setting. Trace element systematics and key provenance ratios (Th/Sc, La/Sc, Cr/Th, La-N/Sm-N,Sm- Eu/Eu & lowast;) indicate heterogeneous source areas dominated by felsic rocks with a minor mafic contribution. The mudrocks of the Moatize and Matinde formations exhibit similar isotopic signatures, with epsilon Nd (t) values of -9.32 +/- 0.74 and -7.99 +/- 1.10, and Nd T-DM model ages of 1.68 +/- 0.08 and 1.51 +/- 0.12 Ga, respectively. These isotopic signatures indicate that both formations were derived from mixed sources, including late Mesoproterozoic and Neoproterozoic rocks from southern Malawi, the Nampula Block (a subdomain of southernmost Malawi), the Guro Suite and the Macossa-Chimoio Nappe. Both Moatize and Matinde mudrocks exhibit high Chemical Index of Alteration (>85) and Chemical Index of Weathering (>90) values, along with low Index of Compositional Variability and low K/Cs ratios. The Al2O3-(CaO + Na2O)-K2O (A-CN-K) relationships indicate that the Moatize and Matinde mudrocks have not undergone post-depositional K-metasomatism. The data collectively indicate intense palaeoweathering conditions in the source areas. Furthermore, the weathering indices suggest warm and humid palaeoclimate during the deposition of the Moatize and Matinde formations. These formations were deposited in a confined continental basin between the Guadalupian (middle Permian) and the Lopingian (late Permian).
Uncertainty-Aware Planning of EV Charging Infrastructure and Renewable Integration in Distribution Networks: A Review
Publication . Tripathy, Sasmita; Fahnbulleh, Edwin Boima; Ghatak, Sriparna Roy; Lopes, Fernando; Acharjee, Parimal
ABSTRACT: Transitioning from internal combustion engines to electric vehicles (EVs) is critical for fighting climate change. This requires widespread adoption of Electric Vehicle Charging Stations (EVCSs). Integrating EVCSs and renewable energy sources (RESs) into distribution networks (DNs) is vital for a sustainable transportation system while enhancing power generation in an environmentally friendly manner. This review explores challenges and opportunities of EVCS and RES integration, concentrating on EV charging-demand uncertainty modeling, forecasting algorithms, planning techniques, and the impacts on DN. It discusses forecasting algorithms in terms of learning-based and non-learning-based methods. EVCS planning algorithms are also discussed, involving deterministic and stochastic methods. The technical, environmental, reliability, and economic impacts of EVCS-RES on DNs are discussed. It explores optimization strategies to minimize these impacts, incorporating them as objective functions. Additionally, the survey examines the methods of incorporating EVs and RES in DN, optimizing EVCS allocation while addressing EVCS impacts on voltage regulation, power loss, and network reliability. The importance of energy management systems and advanced forecasting techniques in balancing power fluctuation and improving efficiency is emphasized. Finally, it identifies open problems and future directions for forecasting and optimizing EVCS-RES integration in the networks. These findings are highly relevant for designing resilient and efficient modern power systems that leverage RES and EVCS in the grids.