Sea ice physical, biological, and chemical properties vary across a wide range of spatial scales, from meters to hundreds or thousands of meters. This spatial variability is commonly attributed to differ-ences in air and ice temperatures, light availability, snow cover thickness, grazing by protozoa, and ocean currents. In situ time series experiments on sea ice are widely used to examine temporal changes in ice algal biomass and photo-physiology in response to specific drivers and light particu-larly. A key assumption in such studies is that observed temporal changes reflect changes in the driving factors rather than spatial variability within the experimental area. Here, we investigate the spatial variability of sea ice physical, chemical properties, ice algal biomass, and algal photobiology at the small spatial scale commonly applied in in situ experiments. Measurements were conducted at 16 sites within a 6 × 6 m plot on land-fast first-year sea ice in Malene Bight, SW Greenland. Sea ice temperature, bulk salinity, Chlorophyll a concentration, and photobiological parameters derived from Pulse Amplitude Modulated (PAM) fluorometry were assessed on the bottom 5 cm of sea ice along with snow depth and sea ice thickness. No statistically significant spatial variability was de-tected for any of the measured parameters, but significant negative correlations were observed be-tween snow depth and maximum quantum yield (ΦPSII_max), and between snow depth and ice thick-ness. The ice algal community was dominated by flagellates (50.4
The article presents the results of mathematical modeling of the coherent combustion process for brown coals from the Alai coal-bearing region (Chukur, Noruskol, Kyzyl-Bulak, Belalma, and Kozhokelen deposits in the Kyrgyz Republic). The study aimed to determine optimal combustion parameters considering the technical characteristics of southern Kyrgyz coals. Using a system of differential equations (Navier-Stokes, heat transfer, combustible particle mass, and Arrhenius), key parameters were calculated: total combustion time, burning rate, and thermal efficiency. It was established that the elevated ash content and moisture levels of certain coals in the Alai coal-bearing region necessitate adjustments to temperature regimes and grinding fineness (dispersion). The optimal particle size for achieving combustion efficiency >95% is 15–45 µm at temperatures of 1450–1550°C. The results provide practical recommendations for designing burner systems and operational regimes for boiler installations in the Kyrgyz Republic.
This study assesses the suitability and technical potential for green hydrogen production in Minas Gerais, Brazil, using a spatially explicit framework. By an Analytic Hierarchy Process, the suitability across 66 microregions is evaluated by applying four main criteria and 22 subcriteria that encompass environmental, resource, infrastructure, and socio-economic factors, weighted by expert judgment. In parallel, the study estimates green hydrogen production potential based on renewable electricity availability from solar, wind, biomass, and residual sources, considering electrolysis. The results indicate a total technical potential of approximately 46 Mt H2 per year, largely dominated by solar energy (86%). Environmental restrictions emerge as the most influential factor in territorial suitability, often outweighing resource availability. Northwestern microregions show higher suitability, while some resource-rich areas remain constrained by environmental factors. Overall, regions with higher suitability align with higher production potential, highlighting the need for integrated planning approaches.
Changes in land use and climate pose major threats to biodiversity 1–5 . However, variation in species responses to climate and land use across space, time, and taxa remains poorly understood 3,6–10 , hindering our ability to predict and mitigate biodiversity change. Here, we evaluate the relative importance of concurrent changes in climate and land use in driving the occurrence and abundance patterns of 503 terrestrial animal species of various taxa over 20 years in Finland. Habitat composition proved to be the main driver of biodiversity patterns but how much and with what uncertainty it explained species distributions depended highly on the context. Specifically, habitat was the dominant driver for butterflies, birds, and small mammals, while habitat and climate were equally important for large mammals and moths. Additionally, species patterns between biogeographical regions were mainly explained by climate, while habitat was the main driver within regions. Traits, such as, body size, pace of life, habitat and diet specialization modulated the relative importance of both drivers’ impacts. Climate and habitat impact on most species were also partially correlated, highlighting the tight connection between the drivers. Our findings emphasize that land use is a major force in shaping terrestrial biodiversity, while highlighting its tight connection with climate. Considering functional and spatial contexts is thus essential for building effective management and conservation strategies for biodiversity under rampant global change.
Background The bipartite begomovirus Tomato leaf curl New Delhi virus causes major losses in solanaceous and cucurbit crops. Viral strains differ in host range, with some infecting both tomato and cucurbits, whereas others are restricted to cucurbits. The viral determinants responsible for these differences remain unclear. Results To identify viral factors controlling host specificity, we compared agroinfectious clones of the cucurbit-restricted CB strain and the Jessore (Jes) strain, which infects both tomato and cucurbits. CB DNA-A infected tomato only when paired with Jes DNA-B, demonstrating that DNA-B determines host specificity. Transient expression of the Jes DNA-B–encoded Nuclear Shuttle Protein (NSP) enabled CB DNA-A + B to systemically infect tomato, identifying NSP as the key host-range determinant. CB caused stronger symptoms in cucumber, and CB DNA-A enhanced virulence in tomato when combined with Jes DNA-B, indicating DNA-A as a determinant of virulence. Co-inoculation of CB DNA-A + B with two monopartite geminiviruses showed that Tomato yellow leaf curl Sardinia virus (TYLCSV) facilitated proliferation and systemic movement of the CB DNA-B component in tomato, whereas CB DNA-A was not detected. Conclusions Our study identifies the NSP as the key viral factor determining host specificity in the two tested ToLCNDV strains, highlights the contribution of DNA-A to virulence, and demonstrates that co-infection with other viruses can influence host adaptation. These insights are valuable for improved prediction of viral epidemics, disease management strategies, and breeding of resistant cultivars.
