National Institute for Research and Development in Environmental Protection

The Cândești necropolis is currently the largest excavated Bronze Age necropolis in Romania, with approximately 800 graves. Notably, one grave from an earlier phase of the Monteoru culture (c. 2200–1850 BC) contained a remarkable necklace composed of 22 perforated gastropod shells and a metal pendant. Our investigation adopted an integrated approach, including taxonomic identification, taphonomic, technological and functional analyses, experimental studies, and physico-chemical investigations (Fourier Transform Infrared Spectroscopy and Raman spectroscopy) of the pigment traces present on the shells’s surface. For the metal pendant, X-Ray Fluorescence analysis was conducted to ascertain its elemental composition. The combined analysis yielded unexpected insights: the shells, belonging to the genus Conus, originated from the Mediterranean region. The perforations were not the result of anthropic intervention; rather, they were the result of natural processes, indicating that the shells were collected from thanatocoenoses. The shells were assembled into the necklace using a thread colored with a red pigment. The perforations show signs of prolonged use, suggesting that the necklace was not only a funerary offering. In conclusion, our study indicated that these exotic shells were collected post-mortem already perforated through a rubbing process in the seashore sediments, transported to the site from a distance, and prior to the death of the owner, had been previously worn as personal adornment before being deposited as grave goods.

In naval operations, a detailed understanding of the operational environment is essential for mission success. At present, environmental assessments within the geospatial, meteorological, and oceanographic (GEOMETOC) domains are significantly improved through the employment of maritime unmanned systems (MUS). These systems are advancing rapidly, delivering information faster while maintaining, or even improving the data quality. However, effective use of these technologies requires not only proficiency in their operation, but also a comprehensive understanding of the characteristic limitations of these systems. This article examines the main systems employed for environmental surveys and outlines the advantages and constraints associated with these platforms and their sensors. This study is derived from observations regarding the utilisation of MUS during a series of experimental activities conducted within the framework of the operational experimentation exercise known as the Robotic Experimentation and Prototyping using Maritime Unmanned Systems (REPMUS) series, covering the period from 2021 to 2025. This exercise, recognised as the largest multinational experimentation initiative, is organised by the Portuguese Navy in collaboration with NATO Center for Marine research and Experimentation (CMRE), Faculty of Porto (FEUP), and European Defence Agency.

The study investigates the influence of different substrates on seed germination and early plant development under controlled environmental conditions, using a specially designed intelligent plant growth simulation system. Experiments were conducted with lettuce and radish seeds sown in peat, garden compost, and podzol. The system allowed precise control of temperature, humidity, soil moisture, light, and carbon dioxide, enabling a reliable comparison of treatments. The initial physical and chemical properties of the substrates were characterized, showing the lowest moisture and density in peat, while compost and podzol displayed higher values and more balanced nutrient content. The results demonstrated that lettuce germinated successfully across all substrates, although peat delayed germination by 5–7 hours and true leaves appearance by up to 12 hours. In radish, the effect was more pronounced: compost and podzol ensured rapid germination (94–95 hours) with high success rates (~98%), whereas peat resulted in delays exceeding 100 hours and germination rates below 25%. Correlation analyses highlighted strong links between delayed germination and reduced performance, especially in peat. Overall, the study confirmed that substrate choice is critical for achieving uniform and efficient germination, with compost and podzol providing optimal conditions, and emphasized the practical value of simulation systems for improving crop establishment.

The purpose of this study was to monitor the biological potential of sunflower cultivation to capitalize on the pedoclimatic conditions in the sandy soil area of southern Oltenia. The results obtained during 2024-2025 showed that sunflowers capitalized on the microclimate in this area, carrying out all the physiological processes of plant growth and development over a period of about 108,9 days, under conditions in which the air recorded a total thermal resource of 2491°C. Positive correlations were highlighted between the soil humus content and the morphological characteristics of the plant, namely, plant height and leaf area index. The seed production obtained from sunflowers varied within the limits of 3281-4326.5 kg, with a thousand-seed weight of 55.8-66.7 g and a hectoliter weight of about 28.7-34.05 kg/hl. The 0.23% increase in soil humus content led to statistically significant differences in seed production and seed quality indices (thousand-seed weight and oil).

Spent mushroom substrate (SMS) could be used as a substrate in anaerobic digestion (AD), but some studies have reported modest production and yield of methane. Several solutions have been proposed to mitigate this issue, such as co-digestion with other substrates, various pretreatments, and the use of additives. In this study we report for the first time the possibility of enhancing the process of methane production from spent Pleurotus substrate (SPS) using a pretreatment with enzymes recovered by a simple aqueous extraction from SPS. This represents an alternative to harsher chemical and physical pretreatment methods. The pretreatment increased the methane production from SPS by 16% at saturation, and a 25% faster anaerobic digestion process was obtained. After 2 days of AD, the methane volume for SPS + enzyme was 287 ± 9 NmL, approaching the maximum of 295 ± 14 NmL obtained for this variant, and was 39% more than SPS without pretreatment (207 ± 16 NmL). Pleurotus cultivation, AD, and the enzymes increased the crystallinity of the substrate. The enzymes increased the chemical oxygen demand, total carbon, and the concentration of pentanoic acid and 2-methyl-butanoic acid and decreased the concentration of hexanoic acid in the liquid digestate. The pretreatment increased, in general, the P and K content in the liquid and solid digestates. All data were compared with the hay used for Pleurotus cultivation.