In ion adsorption rare earth element (REE) deposits, REE are adsorbed onto clay minerals. Previous experimental studies indicate that adsorption depends on the chemical and physical properties of the clay and on the pH and salinity of the solution. This work presents adsorption experiments using two natural, purified kaolins with contrasting particle sizes exposed to different ligands at low and high ionic strengths (I) and at different pH levels to assess their influence on the adsorption of REE onto kaolinite. The results reveal that: (1) REE adsorption is rapid; (2) water/dilute nitric acid experiments gave optimum adsorption; (3) high-I NaCl, Na2SO4 and NaHCO3 demonstrated the least adsorption; (4) REE and yttrium are more adsorbed onto kaolinite in water/dilute nitric acid at lower pH, but adsorption is higher at higher pH when NaCl is present; (5) high I allowed less adsorption; and (6) scandium and thorium are more effectively adsorbed than REE and yttrium. The data suggest inhibition of adsorption by complex ion formation in solution at high I, and in the presence of strongly binding ligands (Cl–, SO42–, CO32–). Adsorption induces no REE fraction for low-I solutions in nitric acid, whereas enhanced chloride complex formation for light REE results in the preferential adsorption of heavy REE. sulphate inhibits adsorption, and carbonate at low I inhibits light REE adsorption relative to heavy REE, whereas at high I kaolinite may dissolve. Low-crystallinity, weathering-derived kaolinite demonstrates an order of magnitude more adsorption than processed, hydrothermal kaolin as a result of its increased surface area and adsorption sites.

Tropical dry forests (TDFs), which comprise 40% of tropical forests and are most widespread in the Neotropics, remain under-researched. TDFs support high biodiversity and are inhabited by many Indigenous communities, making their degradation a critical socio-environmental problem, yet local drivers of deforestation are overlooked. Mexico holds the largest extent of TDFs, yet these ecosystems face high levels of disturbance and limited protection. This study models the impacts of global environmental change on a TDF in southern Mexico, focusing on land-cover dynamics, biodiversity and nature’s contributions to people. We applied spatially explicit land-cover modelling under three long-term scenarios (Optimistic, Business as Usual and Pessimistic) based on varying rates of change, climate and socioeconomic conditions. Drivers were dynamically updated to reflect plausible trajectories. By overlaying land cover with species distribution data, we identified farming expansion as the primary threat to 35 endemic vertebrate species, 27 of which face a high risk of extinction. This biodiversity loss compromises ecosystem functioning and weakens the resilience of local communities. We recommend integrating conservation with Indigenous participation in sustainable land-use practices, aligned with the Kunming–Montreal Global Biodiversity Framework to halt species extinction and conserve ecosystems.

The Curaco Batholith, located in Northern Patagonia (Argentina), is a Late Triassic-Early Jurassic composite intrusive body comprising monzogranites, granodiorites, diorites, granite porphyry, muscovite-bearing leucogranites, mylonites, and andesitic-rhyolitic dikes. This study integrates field mapping, petrographic-microstructural observations, rock magnetic data, and anisotropy of magnetic susceptibility (AMS) analyses across these different facies to investigate the emplacement history of the Curaco batholith within an E-W-trending deformation area. Microstructural analysis allowed classification into three categories: (1) magmatic, encompassing sub-magmatic to high-temperature solid-state, (2) medium-temperature solid-state, and (3) low-temperature solid-state. These were systematically correlated with AMS data. The magnetic fabrics in most lithologies exhibit general NW-SE-trending foliations with subhorizontal to moderately plunging lineations, consistent across the batholith. AMS fabrics within and around the La Seña and Pangaré shear zones share this orientation but display variable dips and lineation plunges. The observed parallelism between magnetic and mesoscopic fabrics, including microgranular enclaves, syn-plutonic dikes, and magmatic foliations in granitic rocks, suggests that strain was recorded progressively during crystallization. The coherent alignment of magmatic, solid-state, and AMS fabrics supports a syn-tectonic emplacement model. At the regional scale, the batholith developed under E-W dextral strike-slip tectonics, whereas at the local scale, emplacement occurred within a right-stepping releasing stepover, producing transtensional conditions. This deformation pattern reflects continuous strain during magma cooling, from magmatic flow to solid-state deformation at progressively lower temperatures, ultimately approaching the brittle-ductile transition. The Curaco Batholith thus records the emplacement of a syn-extensional magma body during the early stages of Gondwana break-up, providing insights into magmatism-transtension interactions in continental settings.

Between 2021 and 2023, the Center for Applied Isotope Studies (CAIS) tested over 500 samples for biobased carbon content under the United States Department of Agriculture’s (USDA) Biopreferred Program using the American Society for Testing and Materials (ASTM) biobased testing standard D6866. We describe some of the novel approaches we used to prepare a diverse array of biobased products and summarize those radiocarbon test results and success rates in meeting the USDA Minimum Biobased Content (MBC).

Hydrogenation of CO2 into high-value carbon-containing compounds can effectively reduce greenhouse gas emissions. These plasma-catalysed systems offer convenient reactions under mild conditions, and, combined with their widely distributed, low-cost clay minerals, they can effectively reduce reaction costs and promote their further industrial application. However, research on their synergistic applications remains limited at present. In this work, we propose a model for synergistic catalytic CO2 conversion by coupling clay minerals and dielectric barrier discharge (DBD) plasma. The synergistic effects of eight typical clay minerals on CO2 conversion and CO selectivity catalysed by DBD and their influencing factors were explored through a combination of performance tests and characterization using X-ray diffraction, scanning electron microscopy and Fourier-transform infrared spectroscopy. Based on the performance and characterization results, minerals exhibiting a two-dimensional tubular structure, increased surface hydroxyl groups, appropriate transition metal active components and low water contents demonstrate greater CO2 conversion rates and CO selectivity. This work demonstrates that clay minerals can be used as effective DBD catalysts and represent low-cost green catalysts for the DBD catalytic system. This is of great significance for the rapid screening of clay minerals that are favourable for CO2 catalytic reactions and their further modification and application.

Deception Island is an active, caldera-forming volcano whose surveillance is critically constrained by its extreme Antarctic isolation, scarce resources and limited seasonal human access. This study addresses these challenges by presenting an innovative Global Navigation Satellite Systems (GNSS) geodetic surveillance framework specifically adapted for such a remote environment. Our approach establishes a key operational distinction between non-real-time monitoring and near-real-time surveillance via a semi-continuous wireless network. We effectively resolve the inherent trade-off between promptness and precision by applying signal enhancement methods (e.g. Kalman filtering) to maintain millimetric accuracy in deformation detection, even when utilizing the high sampling rates (1 Hz) essential for rapid assessment. The resulting model allows for the rigorous isolation of the local volcanic signal from the complex regional tectonic kinematics. Crucially, data analysis reveals recurrent 3 year cycles of inflation and deflation in the magmatic system, strongly correlated with seismicity, which validates ground deformation as a reliable volcanic precursor. The primary practical advance is the validation of a dual-term hazard forecasting system: 1) mid-term (months) forecasts based on long-term time-series analysis to facilitate safe inter-campaign operations and 2) short-term (days) forecasting during periods of unrest using ground displacement acceleration, complemented by a magma injection model to predict the spatial location of potential vent openings. This validated and technologically adjusted framework provides an optimized and transferable template for continuous geodetic surveillance in other isolated, active polar volcanoes.

Attenuation rates inferred from radar sounding offer one of the few ways to observationally constrain the large-scale temperature structure of ice sheets. However, existing methods struggle in regions with near-uniform ice thickness or disrupted radiostratigraphy—common across much of Antarctica and Greenland—where direct temperature estimates are most needed. We adapt the spectral ratio method, originally developed for seismic data, to estimate englacial radar attenuation rates, focusing on regions where traditional methods fail. By analyzing the relative amplitude change of surface and bed reflections across the radar bandwidth, we produce full-column attenuation estimates independent of internal layer continuity or significant variability in bed topography. We apply this method to radar surveys in interior Antarctica and Greenland. Our results agree with attenuation rates derived from borehole temperature profiles and alternative radar-based methods, where comparisons are possible. The spectral ratio method is broadly applicable to any radar dataset that preserves the original amplitude spectra. By expanding the spatial coverage of reliable attenuation estimates, our approach enables continental scale mapping of ice sheet temperature.

Glacial lakes are increasing in number and size worldwide, posing growing risks for outburst floods. Norway’s last glacial lake inventory used semi-automatic mapping on Sentinel-2 imagery from 2018–19. In this study, we test a more automated and reproducible workflow for updating glacial lake extents in Norway using Sentinel-2 and Sentinel-1 satellite imagery and a Random Forest classifier. Here, glacial lakes are defined as water bodies within 200 m of glaciers larger than 0.1 km2 with a minimum lake size of 400 m2. A 10th-percentile Sentinel-2 summer composite from 2023–24 mitigated snow and cloud cover, while Sentinel-1 ascending-descending difference composites reduced shadow misclassification without relying on DEMs. Validation across six glacier regions shows high detection reliability (F1-score: 0.81) as well as high delineation accuracy (median deviation <6.5 m). However, manual correction remains necessary, especially in steep terrain. We identified 1382 glacial lakes in 2023–24, covering 124 km2—a substantial increase relative to 2018–19. Excluding regulated lakes and adjusting for methodological differences, we estimate a 9–22% lake area increase over the past five years, mainly driven by glacier retreat. The workflow is efficient and reproducible, but regional threshold adaptation and retraining are required for transfer to other regions.

Blastoids have three primary systems providing entrances to blastoid hydrospires, the primary organ for respiration: (1) exposed hydrospire slits formed across the width of the radiodeltoid suture; (2) hydrospire pores formed at the aboral ends of the ambulacra; and (3) hydrospire tubules formed as invaginations along the radiodeltoid suture, becoming openings that pierce the radials and deltoids ontogenetically. Blastoid classification historically divided the blastoids into two groups—the Fissiculata and Spiraculata. The Fissiculata comprised those blastoids that have exposed hydrospire slits or spiracular slits. The Spiraculata had hydrospire pores and spiracles that connect internally to hydrospires. Spiraculate classification focused on the configuration of the spiracles and anispiracle in combination with thecal form. Spiracles are the adoral consequence of the ambulacra infilling the radial sinus and covering the hydrospires by the lancet and the side plates and are found in all spiraculate blastoids. In this revision of blastoid classification, we place primacy on the three mechanisms by which water is drawn into the hydrospires—hydrospire slits open to seawater, hydrospire pores, and hydrospire tubules. Hydrospire tubules are formed along the radiodeltoid suture, a very different ontogenetic position from hydrospire pores, which are formed at the aboral end of the ambulacrum, and a fundamental phylogenetic difference. We herein abandon the term Spiraculata and refer to the spiraculate grade as being the Stomatoblastida, new superorder for spiraculates with hydrospire pores and the Tubuloblastida, new superorder for spiraculates with hydrospire tubules. The Fissiculata is elevated to superordinal status.

An alpine glacier below Sunlight Peak in northwest Wyoming was first photographically documented in 1893, near the end of the Little Ice Age and during the time of industrialization. Since then, evolving technologies have been applied to observe this glacier and nearby discontinuous permafrost for studies spanning Earth, environmental, and planetary sciences. Surveys in the 21st century indicate negative mass balance coinciding with rising average air temperature. This paper reviews the geological and geophysical data on record for the Sunlight Glacier system, presents new results from a 2023 fieldwork campaign combined with remote sensing analysis and comments on likely scenarios of future evolution for this individual body of ice within a broader alpine cryosphere feeding the watersheds of western North America.

An important question in evolutionary biology and macroecology is whether taxa show systematic trajectories in occupancy, the proportion of geographic area occupied, over macroevolutionary timescales. Past studies have used fossils to document these trajectories, showing a symmetric rise and fall. In this study, I focus on several biases in the analyses of fossil occupancy trajectories that have been unaccounted for. First, better sampling of boundary bins in a taxon’s stratigraphic range, paradoxically, results in lower mean occupancy of taxa in those bins. This is because better sampling allowed more taxa with low occupancies to be included in the mean occupancies of those bins compared with intermediate bins. Second, the possibility that taxa may have incomplete durations within boundary bins could also lower occupancies in those bins. Finally, a bias can also exist when the number of sampled sites is not constant throughout a taxon’s stratigraphic range. I use simulations to show that the first bias can be corrected by conditioning these boundary bins to be sampled in the same way as intermediate bins. To mitigate the second bias, I use higher-resolution time bins to constrain the intervals over which taxa’s occupancies are measured so that they are comparable between boundary and intermediate time bins. I also present an approach that can correct for the last bias by subsampling geographic sites, testing its impact in a simulation. Considering these factors, the occupancy trajectories of marine animal genera look to be a relatively gradual rise post-origination with a sudden decline before extinction.