Browsing by Issue Date, starting with "2024-10-29"
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- Diverse prehistoric cattle husbandry strategies in the forests of Central Europe.Publication . Gillis, Rosalind; Kendall, Iain P; Roffet-Salque, Mélanie; Zanon, Marco; Anders, Alexandra; Arbogast, Rose-Marie; Bogucki, Peter; Brychova, Veronika; Casanova, Emmanuelle; Classen, Erich; Csengeri, Piroska; Czerniak, Lech; Domboróczki, László; Fiorillo, Denis; Gronenborn, Detlef; Hachem, Lamys; Jakucs, János; Ilett, Michael; Lyublyanovics, Kyra; Lenneis, Eva; Marciniak, Arkadiusz; Marton, Tibor; Oross, Krisztián; Pavúk, Juraj; Pechtl, Joachim; Pyzel, Joanna; Stadler, Peter; Stäuble, Harald; Vostrovská, Ivana; van Wijk, Ivo; Vigne, Jean-Denis; Balasse, Marie; Evershed, Richard PDuring the sixth millennium bce, the first farmers of Central Europe rapidly expanded across a varied mosaic of forested environments. Such environments would have offered important sources of mineral-rich animal feed and shelter, prompting the question: to what extent did early farmers exploit forests to raise their herds? Here, to resolve this, we have assembled multi-regional datasets, comprising bulk and compound-specific stable isotope values from zooarchaeological remains and pottery, and conducted cross-correlation analyses within a palaeo-environmental framework. Our findings reveal a diversity of pasturing strategies for cattle employed by early farmers, with a notable emphasis on intensive utilization of forests for grazing and seasonal foddering in some regions. This experimentation with forest-based animal feeds by early farmers would have enhanced animal fertility and milk yields for human consumption, concurrently contributing to the expansion of prehistoric farming settlements and the transformation of forest ecosystems. Our study emphasizes the intricate relationship that existed between early farmers and forested landscapes, shedding light on the adaptive dynamics that shaped humans, animals and environments in the past. Stable isotope analysis of zooarchaeological remains and pottery in a palaeo-environmental framework reveals that early Central European farmers utilized diverse regional pasturing strategies for cattle, including the use of forested environments for grazing and seasonal foddering.
- Ecohydrological assessment of a complex river-floodplain system for the enhancement of its multidimensional potentialPublication . Guzmán, Damaris Rios; Chicharo, Luis; Jarosiewicz, PawełRiver floodplain systems are critical for sustaining biodiversity and providing a wide range of ecosystem services. However, climate change and anthropogenic activities increasingly disrupt the hydrological and ecological connectivity of these systems, red ucing their resilience to external pressures. The degradation of floodplains undermines key ecosystem services, including the support of terrestrial and aquatic biodiversity, the regulation of hydrological extremes such as floods and droughts, and the sequ estration of carbon. Given the global challenges of water scarcity and associated ecological consequences, there is an urgent need for innovative management strategies to enhance the mult idimensional roles of floodplains in water resource management, biodiversity conservation, and climate change adaptation. Therefore, this thesis focused on the study of the river floodplain system that was selected as the demonstration site for the ecohydrological project LIFE Pilica (LIFE19 IPE/PL/000005) in Central Poland. The study addresse d the hydrological connectivity within the river floodplain system during spring and early summer, assessing its effects on water quality. A particular focus was placed on phosphorus dynamics between the water and sediment compartments, aiming to propose management strategies that mitigat e excessive phosphorus release for a sustainable water retention in the floodplain area. Three primary hydrological connection s were identified between the studied floodplain, Pilica river and an upstream wetland . The connectivity decreased significantly throughout the study (from 0.185 m 3 s 1 in March to 0.002 m 3 s 1 in May )), with the first connection turning into a drainage source in April due to Pilica’s water level decrease . By May, the second source dried up, and the third was projected to cease at a river discharge below 12 m³s⁻¹ (R² = 0.94). Principal Component Analysis (PCA) revealed a greater difference between water quality from the o xbow l ake with the river ’s inflow (35.4%) than with the wetland’s outflow ( 15.5%). This shift underscores an increased risk of eutrophication in both water bodies, driven by prolonged residence times, nutrient accumulation, and the lack of water exchange from the river. Sediment analysis revealed significant differences in water content and organic matter between samples ( p < 0.05 at the studied floodplain part . Most sediments were rich in organic phosphorus and bound to Fe, Al, and Mn. Sorption tests showed greater phosphorus adsorption in air dried sediments and a high zero equilibrium phosphorus concentration (EPC₀), indicating a tendency to release phosphoru s when exposed to river water , thus highlighting the need of proper management prior increasing hydrological connectivity . In conclusion, the implementation of a water retention basin in the area will tackle the greatest threat to the studied river floodplain system: the progressive loss of hydrological connectivity. Furthermore, the potential risk of phosphorus release was ev aluated to refine the management strategy , ensuring it effectively mitigates nutrient loading and supports long term ecosystem health.
- Multimodal sentiment classifier for various environments contextsPublication . Silva, Nelson André Sardo da; Cardoso, Pedro J. S.; Rodrigues, João M. F.A análise de sentimentos é um método eficaz para determinar a opinião pública. As publicações nas redes sociais têm sido objeto de muita investigação, principalmente devido à enorme e diversificada base de utilizadores dessas plataformas que partilham regularmente opiniões sobre praticamente todos os assuntos. No entanto, nas publicações (posts) compostas por um par texto-imagem, a descrição escrita pode ou não transmitir o mesmo sentimento que a imagem. Este estudo utiliza modelos de aprendizagem automática para a avaliação automática do sentimento de pares de texto e imagem(ns). Os sentimentos derivados da imagem e do texto são avaliados de forma independente e associados (ou não) para formar o sentimento global, devolvendo o sentimento da publicação e a discrepância entre os sentimentos representados pelo par texto-imagem. A classificação do sentimento da imagem é dividida em 4 categorias: “interior” (IND), “exterior feito pelo homem” (OMM), “exterior não feito pelo homem” (ONMM) e “interior/exterior com pessoas em segundo plano” (IOwPB). No final, os resultados são consolidados num modelo de classificação do sentimento da imagem (ISC), que pode ser comparado com um classificador holístico do sentimento da imagem (HISC), mostrando que o ISC obtém melhores resultados do que o HISC. Para um subconjunto de dados do Flickr, a classificação do sentimento das imagens, por categoria, atingiu uma exatidão de 68,50% para IND, 83,20% para OMM, 84,50% para ONMM, 84,80% para IOwPB e 76,45% para ISC, em comparação com 65,97% do HISC. Para a classificação do sentimento do texto, num subconjunto da base de dados B-T4SA, foi alcançada uma exatidão de 92,10%. Por fim, a combinação texto-imagem, num conjunto de dados privado, obteve uma exatidão de 78,84%.
- Ecological and socioeconomic aspects of subsistence fisheries in the Central Africa: The case study of "peixinho" fishery of São Tomé and PríncipePublication . Ejarque, Maria Compte; Baptista, Vânia; Albo Puigserver, MartaThe riparian goby-fry fishery of São Tomé and Príncipe, or “peixinho” fishery, is part of the culture of the fishing communities located next to the water courses from the archipelago. The fishery consists on the capture of amphidromous gobiid post-larvae species, Sicydium brevifile, Sicydium bustamantei, Awaous bustamantei and Awaous lateristiga, during their up-stream migration. This study attempts to describe the fishery and its role in their communities, through the local ecological knowledge (LEK) from fishers gathered throughout semi-structured interviews and cross-checked with the fishing communities and the fishery expert using a member-checking approach. The majority of the fishers are middle-aged women who use nylon nets, traditional traps called "tchanga", mosquito nets and cloth nets. The choice of fishing gear and tactics varies geographically and depending on the age. Correlation between rainy season and lunar phases, specifically the new moon and last quarter phases, with higher catches was indicated by the fishers. However, this association could not be completely confirmed based on the catch per unit effort (CPUE) collected in the interviews. Although fishers consider the fishing activity as commercial, most do not sell the entire catch, revealing that the fishery still has a subsistence component due to its importance for the livelihood and food security of the fishing communities, who are aware of the detriment of the fishery, but remain hesitant of management measures. This study outlines for the first time the socio-ecological system of the “peixinho” fishery, in order to comprehend the ecosystem services in which fishing communities depend on and to promote participatory approaches.
- Integrating seaweed in a marine fish RASPublication . Martins, Diogo Miguel Marreiros; Quintã, Raquel; Aragão, CláudiaAquaculture is, nowadays, one of the sectors with a crucial impact on the human food supply. Sustainability in this sector has become a primary goal and is directly connected to recirculating aquaculture systems. These systems hold great promise for the future, but improvements in water quality are needed due to the high accumulation of metabolic waste. Water quality may be improved by integrating macroalgae into these systems, as they have excellent bioremediation capabilities. This study aimed to implement an Integrated Recirculating Aquaculture System (IRAS) with Ulva sp. and fish to assess macroalgae bioremediation capacity and improve water quality and fish performance in comparison to a fish Recirculating Aquaculture System (RAS). Macroalgae capacity in bioremediation highly depends on their growth and nutrient availability in the system. So, this work included sampling of dissolved nutrients and weekly samplings for assessing biomass production, at different densities (1.0, 1.5, and 2.0 kg FW m-2), and assessment of nitrogen content in the macroalgae produced. Results showed that the highest growth rate was found for Ulva sp. stocking density 1.0 kg FW m-2, while N yield did not differ between the stocking densities tested. The Ulva sp. improvement in water quality parameters was not significant when compared to RAS treatment. Fish performance was not significantly different between treatments and no differences were observed in hematological and histological parameters. The gills presented some anomalies but were classified with minor signs of pathology. The results demonstrate that lower Ulva sp. stocking densities resulted in higher growth, indicating that this macroalgae can be a potential candidate for IRAS, but more research is needed to use the bioremediation capability to improve water quality in these systems.