We report the first confirmed records of two widely distributed Antarctic bdelloid rotifer species, Philodina gregaria and Adineta grandis, from the Syowa Oasis, East Antarctica. To verify their taxonomic identity, we applied an integrative approach combining morphological observations, mitochondrial cytochrome c oxidase subunit I (COI) sequencing, Bayesian tree reconstruction, and four species-delimitation methods (GMYC, bPTP, ABGD, and ASAP). COI sequences obtained from specimens collected in the Syowa Oasis were compared with previously published sequences from Vestfold Hills and Victoria Land. Morphological characteristics and morphometric measurements were consistent with previous descriptions of both species. Across the species-delimitation analyses, specimens from the Syowa Oasis were consistently assigned to the same species-level entities as previously reported Antarctic populations of A. grandis and Ph. gregaria. These results provide robust morphological and molecular evidence for the presence of A. grandis and Ph. gregaria in the Syowa Oasis, filling a geographic gap in the known Antarctic distributions of these two species and providing further evidence of their broad occurrence across Antarctic ice-free regions.
Mineral dust is one of the major light-absorbing impurities in snow and ice, and affects snowpack and glacier melting. However, the origin and composition of mineral dust deposited on snow surfaces, and how these vary over time and space, remain poorly understood. This study examined the temporal and spatial variability in the composition of mineral dust in an alpine snowpack in the Tateyama Mountains, Japan and evaluated the relative contributions of long-range-transported and locally derived dust to dust deposition on the snow surface. Surface snow samples collected from April to July were analyzed using microscopy, SEM–EDS, and X-ray diffraction analyses (XRD). The results showed a clear temporal transition in the mineral assemblages. The April samples were dominated by quartz and feldspar, consistent with long-range-transported Asian dust. Conversely, samples from May to July showed increasing abundances of chlorite, biotite, and amphibole, indicating a growing contribution of locally derived dust during the melt season. Coarse, feldspar-rich dust was frequently observed near diorite outcrops. These results indicate that Asian dust dominated in spring, whereas locally derived dust increasingly contributed to the mineral composition of surface snow during the melt season. This suggests that local geology plays an important role in controlling snowpack impurity composition, with potential implications for snow-surface radiative properties.
The LODEWAVE project was designed to observe the horizontal distribution of momentum transport caused by atmospheric gravity waves (GWs) in the lower stratosphere over Antarctica using super-pressure (SP) balloons. SP balloons maintain constant buoyancy, enabling them to drift along isopycnal surfaces for extended periods (up to 1 month). Ventilation during level flight of SP balloons is nearly zero. Therefore, the thermistor tends to be heated by solar radiation, leading to a significant overestimation of the actual air temperature. To date, similar radiative effects have been observed during the two LODEWAVE campaigns. In addition to solar heating, the temperature data were affected by heat flow from the payload, resulting in reduced accuracy. As accurate temperature measurements are essential for GW analysis and for data assimilation into numerical models, we applied corrections for both solar radiation and heat flow effects. The correction was performed using a correction formula that accounts for ventilation. As a result of the correction, the deviation from ERA5 was reduced, indicating that the effects of solar radiation and heat flow have been successfully reduced. Furthermore, the corrected data revealed a dependence on surface conditions during flight.
This article examines the resistance of Evenki reindeer herders and hunters in East Siberia and the Russian Far East to colonial, Soviet, and post-Soviet resource-extraction projects. Drawing on long-term ethnographic fieldwork conducted between 2004 and 2020, alongside historical and archival material, the article traces a continuum from seventeenth-century resistance to the yasak fur-tribute system, through the armed Tungusic uprising of 1924-1925 and the 1927 confederalist movement in Yakutia, and the Tuguro-Chumikan insurgency of 1930–1932, to the Evenki guerrilla campaign of 1942-1943 and contemporary conflicts between Evenki communities and gold-mining companies in Ivanovskoe and Tiania. Rather than treating these episodes as isolated or as evidence of Evenki passivity, the article argues that they form a sustained, if historically interrupted, response to extraction without reciprocity. Centering the Evenki cosmological concept of diaptygin, the gluttonous consumer who takes without sharing, the article shows how Evenki communities have repeatedly contested state and corporate claims to sovereign authority over Indigenous lands through strategic mobility, the withholding of labor and environmental knowledge, collective self-organization, legal mobilization, and, when necessary, force.
Observations of the deep Forbush decrease (FD) during 1 June 2025 in neutron and gamma-ray measurements are presented here. Multiple coronal mass ejections (CMEs) erupted from the Sun and subsequently interacted in interplanetary space, likely producing the large-amplitude, long-duration FD was observed by neutron monitors worldwide and the NaI(Tl) scintillation detector at Maitri, Antarctica. A similar FD signature was also reported in muon observations from the SEVAN network. This FD was investigated using interplanetary magnetic field (IMF) and solar wind parameters obtained from Aditya-L1, India's first mission to the Sun-Earth Lagrangian point L1, with observations from the MAG and ASPEX-SWIS payloads. An initial sharp decrease at ∼10 UT on 1 June, followed by a second minimum at ∼17 UT, was observed in all three types of secondary cosmic rays (SCRs). A total decrease of ∼18% was observed in neutron flux, while a decrease of ∼7% was recorded in gamma-ray flux. Interestingly, 90-min running-averaged data of the GOES-18 proton flux above 275 MeV also showed a clear FD signature. During the extended recovery phase, several fluctuations were observed in the gamma-ray and neutron fluxes at Antarctica. Wavelet analysis revealed a prominent 24-h periodicity in both SCR fluxes.
