Antarctic Soils Select Copiotroph-Dominated Bacteria.

The life strategies of bacterial communities determine their structure and function and are an important driver of biogeochemical cycling. However, the variations in these strategies under different soil resource conditions remain largely unknown. We explored the bacterial life strategies and changes in structure and functions between Antarctic soils and forest (temperate, subtropical, and tropical) soils. The results showed that the weighted mean rRNA operon copy number in temperate soils was 19.5% lower than that in Antarctic soils, whereas no significant differences were observed among Antarctic, subtropical, and tropical soils. An unexpected result was that bacterial communities in Antarctic soils tended to be copiotrophs, such as Actinobacteriota and Bacteroidota, whereas those in temperate soils tended to be oligotrophs, such as Acidobacteriota and Chloroflexi. Functional predictions showed that in comparison to copiotrophs in Antarctic soils, temperate-inhabiting oligotrophic bacteria exhibited an 84.2-91.1% lower abundance of labile C decomposition genes (hemicellulose, cellulose, monosaccharides, and disaccharides), whereas a 74.4% higher abundance of stable C decomposition (lignin). Genes involved in N cycling (nitrogen fixation, assimilatory nitrate reduction, and denitrification) were 24.3-64.4% lower in temperate soils than in Antarctic soils. Collectively, our study provides a framework for describing the life strategies of soil bacteria, which are crucial to global biogeochemical cycles.

Biomass burning records of the Shulehe Glacier No. 4 from Qilian Mountains, Northeastern Tibetan Plateau.

Biomass burning play a key role in the global carbon cycle by altering the atmospheric composition, and affect regional and global climate. Despite its importance, a very few high-resolution records are available worldwide, especially for recent climate change. This study analyzes levoglucosan, a specific tracer of biomass burning emissions, in a 38-year ice core retrieved from the Shulehe Glacier No. 4, northeastern Tibetan Plateau. The levoglucosan concentration in the Shulehe Glacier No. 4 ice core ranged from 0.1 to 55 ng mL-1, with an average concentration of 8 ± 8 ng mL-1. The concentrations showed a decreasing trend from 2002 to 2018. Meanwhile, regional wildfire activities in Central Asian also exhibited a declining trend during the same period, suggesting the potential correspondence between levoglucosan concentration of the Shulehe Glacier No. 4 ice core and the fire activity of Central Asia. Furthermore, a positive correlation also exists between the levoglucosan concentration of the Shulehe Glacier No. 4 ice core and the wildfire counts in Central Asia from 2002 to 2018. While backward air mass trajectory analysis and fire spots data showed a higher distribution of fire counts in South Asia compared to Central Asia, but the dominance of westerly circulation in the northern TP throughout the year. Therefore, the levoglucosan in the Shulehe Glacier No. 4 provides clear evidence of Central Asian wildfire influence on Tibetan Plateau glaciers through westerlies. This highlights a great importance of ice core data for wildfire history reconstruction in the Tibetan Plateau Glacier regions.

The determining factors of hydrogen isotope offsets between plants and their source waters.

A fundamental assumption when using hydrogen and oxygen stable isotopes to understand ecohydrological processes is that no isotope fractionation occurs during plant water uptake/transport/redistribution. A growing body of evidence has indicated that hydrogen isotope fractionation occurs in certain environments or for certain plant species. However, whether the plant water source hydrogen isotope offset (δ2 H offset) is a common phenomenon and how it varies among different climates and plant functional types remains unclear. Here, we demonstrated the presence of positive, negative, and zero offsets based on extensive observations of 12 plant species of 635 paired stable isotopic compositions along a strong climate gradient within an inland river basin. Both temperature and relative humidity affected δ2 H offsets. In cool and moist environments, temperature mainly affected δ2 H offsets negatively due to its role in physiological activity. In warm and dry environments, relative humidity mainly affected δ2 H offsets, likely by impacting plant leaf stomatal conductance. These δ2 H offsets also showed substantial linkages with leaf water 18 O enrichment, an indicator of transpiration and evaporative demand. Further studies focusing on the ecophysiological and biochemical understanding of plant δ2 H dynamics under specific environments are essential for understanding regional ecohydrological processes and for conducting paleoclimate reconstructions.

Higher temperature sensitivity of retrogressive thaw slump activity in the Arctic compared to the Third Pole.

Climate change exacerbates permafrost thawing, resulting exceptionally intense retrogressive thaw slump (RTS) activity in the Arctic and Third Pole. However, comparative assessments of permafrost characteristics and RTS sensitivity under warming climate at both poles are still lacking. Here, the severity and temperature sensitivity of RTS were presented and compared using Tasselled Cap (TC) trend analysis of time-series Landsat images and Interferometric Synthetic Aperture Radar (InSAR) measurement. RTS has a more severe growth trend in the Arctic cold permafrost region, also with a deformation rate of approximately 70 mm/year and cumulative displacement up to 120 mm. In comparison, the deformation rate in the Third Pole is approximately 50 mm/year. The RTS severity in the Arctic is about 1.5 times higher than in the Third Pole, primarily owing to different sensitivities of cold and warm permafrost under warming climate. The intensification and vulnerability of RTS have global implications on climatological processes, hydrology, carbon release and ground stability, thus calling for attention and effective governance action.

Extreme precipitation stable isotopic compositions reveal unexpected summer monsoon incursions in the Qilian Mountains.

Isotope composition and moisture sources of precipitation are important for understanding water cycles and reconstructing paleoclimate. Based on 15-years' precipitation stable Isotope composition (δ18O and δ2H) from four stations of the Qilian Mountains, we found unique δ18O and δ2H features associated with the incursion of the summer monsoon over the Qilian Mountains, northwestern China. In 12 of the 15 years, similar seasonal variations of δ18O and δ2H confirmed a dominant source of moisture from Westerly circulation, and higher intercepts of the local meteoric water line (LMWL) indicated strong recycling of continental moisture. However, in August 2016 and 2018, extremely low slopes and intercepts of the LMWL, and more negative δ18O and δ2H revealed substantial contributions of the Asian summer monsoon to precipitation of the Qilian Mountains, with extremely heavy precipitation in August 2016. The column moisture flux, land-sea thermal contrast, correlations of precipitation δ18O with East Asian Summer Monsoon Index and Westerlies Index, HYSPLIT modeling results and precipitation δ18O along backward trajectories confirmed incursions of the summer monsoon in August 2016 and 2018. Our redefining of the boundary of the summer monsoon region confirmed the summer monsoon incursion zone can extend to the west of longitude 96°E and north of latitude 40°N in strong monsoon years, corresponding to boundaries of monsoon incursions in the mid-Holocene. Temperature correlated with precipitation δ18O at monthly and shorter time scales, but not for whole seasons or at yearly scale, revealing that summer monsoon incursions are therefore more likely than changing temperature to explain the multi-year cycles in the Qilian Mountains ice archives. Continent-scale shifts in atmospheric circulation strongly influence water resources in the Qilian mountains, and may change in frequency as climate warms. This study therefore has important implications for understanding water resources in the Qilian mountains in the past and into the future.

Pollution revealed by stable lead isotopes in recent snow from the northern and central Tibetan Plateau.

Lead (Pb) isotopes are less fractionated than those from different sources, and thus were used to trace the sources of Pb in the environment. To investigate the sources of Pb in the atmosphere of the Tibetan Plateau, stable Pb isotopes (206Pb, 207Pb and 208Pb) in acidified snow pit samples collected from five glaciers (i.e., Qiyi-QY, Meikuang-MK, Yuzhufeng-YZF, Hariqin-HRQ and Xiaodongkemadi-XDKMD) in May 2016 of the northern and central Tibetan Plateau were measured. The results showed narrow ranges of 1.158-1.187 for 206Pb/207Pb and 2.450-2.489 for 208Pb/207Pb respectively. The 206Pb/207Pb ratios in all samples were obviously lower than the environmental background value of 1.196, indicating the primary contributions of anthropogenic sources. At least 60% of Pb was contributed by various human activities, which was supported by the Pb isotopes in the snow pit samples from the QY, MK, YZF, HRQ and XDKMD glaciers. By comparing Pb isotope data, we found that the primary anthropogenic sources are coal combustion, mining and smelting activities in northwestern China and mixed emissions from cities located in western China and close to the glaciers. These sources contributed to the Pb in the northern glaciers (QY and MK) in particular. Coal combustion in India probably contributes to the central glaciers (HRQ and XDKMD). Another potential source could be parts of central Asia (e.g., Kyrgyzstan and Uzbekistan) through long range transport. The above potential source areas of contaminants were traced further by the air mass back-trajectory tracing method.

Highly sensitive ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry detection method for levoglucosan based on Na+ enhancing its ionization efficiency.

The sensitive determination of levoglucosan in aqueous samples has great significance for the study of biomass burning. Although some sensitive high-performance liquid chromatography/mass spectrometry (HPLC/MS) detection methods have been developed for levoglucosan, there are still plenty of shortcomings, such as complicated sample pre-treatment procedures, large-amount sample requirements, and poor reproducibility. Herein, a new method for the determination of levoglucosan in the aqueous sample was developed using ultra-performance liquid chromatography with triple quadrupole mass spectrometry (UPLC-MS/MS). In this method, we firstly found that compared with H+, Na+ could effectively enhance the ionization efficiency of levoglucosan, even though the content of H+ is higher in the environment. Moreover, the precursor ion m/z 185.1 [M + Na]+ could be used as a quantitative ion to sensitively detect levoglucosan in aqueous samples. Only 2 µL of un-pretreated sample is required for one injection in this method, and great linearity was obtained (R 2 = 0.9992) using the external standard method when the concentration of levoglucosan was 0.5-50 ng mL-1. The limit of detection (LOD) and quantification (LOQ) were 0.1 ng mL-1 (0.2 pg absolute mass injected) and 0.3 ng mL-1, respectively. Acceptable repeatability, reproducibility, and recovery were achieved. This method has the advantages of high sensitivity, good stability, good reproducibility, and simple operation, which could be widely used for the detection of different concentrations of levoglucosan in various water samples, especially for the detection of samples with low content such as ice core or snow samples.

Paleochannel of the Yellow River within the Zoige Basin and its environmental significance on the NE Tibetan Plateau.

Paleochannel sedimentary sequences can provide abundant information on regional environmental changes. A typical paleochannel (paleo-oxbow lake type) section of the Yellow River was identified within the Zoige Basin on the NE Tibetan Plateau. A multi-index approach was used to accurately identify sediments of different genetic types, such as riverbed deposits of the Yellow River, paleo-oxbow lake deposits, and overbank flood deposits (OFD) in the section. Based on optically stimulated luminescence (OSL) and AMS 14C dates, we examined the environmental evolution recorded by the section. The results show that: (1) The section is a record of environmental change since 4.17 ± 0.49 ka. During 4.17 ± 0.49 to 3.24 ± 0.26 ka, the ancient Yellow River occupied the channel. At 3.24 ± 0.26 ka, the paleochannel experienced a neck cutoff, and the fluvial environment began to change into the oxbow lake environment. After 2.45 ± 0.11 ka, the paleo-oxbow lake gradually disappeared. Subalpine meadow soil has developed at this site since 1.31 ± 0.05 ka. (2) Paleoenvironmental proxies indicate that the Zoige Basin was warmer and wetter before ~3.00 ka, and became drier and colder after ~3.00 ka, which may be mainly related to the weakening of the East Asian summer monsoon (EASM) and the strengthening of the Westerlies. (3) Two episodes of extreme overbank flooding occurred at 2.96 ± 0.24 to 2.87 ± 0.27 ka and 1.84 ± 0.20 to 1.70 ± 0.16 ka, correlated with climate shift period from the mid-Holocene climatic optimum to the late Holocene and the Dark Age Cold Period (DACP), respectively. Due to the relatively cold and dry climate in these periods, glaciers generally advanced on the Tibetan Plateau, and the contribution of snow and ice meltwater weakened. Therefore, the strong rainfall caused by the abnormal atmospheric circulation may be the main cause of these extreme overbank flooding.

Sustainable evaluation of the eco-economic systems in the π-shaped Curve Area of the Yellow River basin of China: a study based on the 3D ecological footprint model.

Sustainable evaluation of the eco-economic systems is crucial to resolve the contradiction between environmental protection and economic development and promote healthy urban development. This paper constructed an SEC framework for sustainable development index (SDI) evaluation of the eco-economic systems in the π-shaped Curve Area in the Yellow River basin based on the 3D ecological footprint (EF) model. The study was conducted from three aspects: the capital utilization scale and equity during the ecological supply and demand process, the development efficiency and capacity of the eco-economic systems, and the relations between the systems embodied by the coordination and security evaluation. Also, the SDI and its influence mechanism were studied using the fully arrayed polygon diagram and geographic detector. Findings include the following: EF depth is higher in cities with poor natural resources, while EF size is higher in cities with vast territories and rich resources. The arrangement of EF depth and EF size presents nearly a reverse trend, and the consumption of capital flow and capital stock complements each other. Cities can be classified as heavy utilization type, moderate utilization type, mild utilization type, and low stock appropriation type. From 2005 to 2019, the area's SDI and the three aspects presented evident spatial heterogeneity and formed clusters. The role of government, energy consumption, scientific innovation, industrial structure, urbanization rate, population, economic level, and openness level impact SDI differently. This study proposed a new insight for the sustainability evaluation of eco-economic systems.

Spatial variations on the hydrochemistry, controls, and solute sources of surface water in the Weihe River Basin, China.

The Weihe River Basin (WRB), the largest tributary of the Yellow River Basin (YRB), is located in the northwest of China. As the "mother river" of the Guanzhong Plain, it plays an important role in the development of Guanzhong City Group. Based on pH, electric conductivity (EC), total dissolved solids (TDS), and major ionic concentrations of 227 samples collected from the main stream (MS), northern tributaries (NT), and southern tributaries (ST) of the WRB, we explored spatial differential characteristics of hydrochemistry and their controlling factors, solute sources, and water quality of surface water. The results revealed mildly alkaline pH and much higher TDS values than the global average with mean values of 7.9 and 1037.7 mg L-1, respectively. Except NO3-, the concentrations of major ions in the MS and NT were higher than those of the ST, with similar spatial distribution patterns of Ca2+, Na+, Mg2+, SO42-, and Cl-. Na+ and SO42- were the most dominant cation and anion in the MS and NT controlled by both rock weathering and evaporation-crystallization processes. Ca2+ and HCO3- were the most dominant cation and anion in the ST mainly controlled by rock weathering process. Evaporite dissolution contributed the most to dissolved solutes in the MS and NT, while carbonate weathering dominated dissolved solutes in the ST. These findings were confirmed by the results of correlation matrix, principal component analysis (PCA), stoichiometric plots, and different water types identified as Na-SO4·Cl in the MS and NT, and Ca-HCO3 in the ST. Atmospheric and anthropogenic inputs had a minor effect on the surface water chemistry. However, human activities could not be ignored in the ST accounting for 10.9% of the total dissolved solutes, mainly because of the fertilizer application. And the surface water of the ST was more suitable for irrigation and drinking purposes than that of the MS and NT. Knowledge of our findings could contribute new insights to the solute geochemistry and sustainable management of water resources in the lithologically distinct segments of the WRB and other similar areas.

Spatial distribution and potential sources of arsenic and water-soluble ions in the snow at Ili River Valley, China.

Trace elements and water-soluble ions in snow can be used as indicators to reveal natural and anthropogenic emissions. To understand the chemical composition, characteristics of snow and their potential sources in the Ili River Valley (IRV), snow samples were collected from 17 sites in the IRV from December 2018 to March 2019. Inverse distance weighting, enrichment factor (EF) analysis, and backward trajectory modelling were applied to evaluate the spatial distributions and sources of water-soluble ions and dissolved arsenic (As) in snow. The results indicate that Ca2+ and SO42- were the dominant ions, and the concentrations of As ranged from 0.09 to 0.503 µg L-1. High concentrations of As were distributed in the northwest and middle of the IRV, and the concentrations of the major ions were high in the west of the IRV. The strong correlation of As with F-, SO42-, and NO2- demonstrates that As mainly originated from coal-burning and agricultural activities. Principal component analysis showed that the ions originated from a combination of anthropogenic and crustal sources. The EFs showed that K+, SO42-, and Mg2+ were mainly influenced by human activities. Backward trajectory cluster analysis suggested that the chemical composition of snow was affected by soil dust transport from the western air mass, the unique terrain, and local anthropogenic activities. These results provide important scientific insights for atmospheric environmental management and agricultural production within the IRV.

Distinct impacts of vapor transport from the tropical oceans on the regional glacier retreat over the Qinghai-Tibet Plateau.

An influence of precipitation on the glacier changes over the Qinghai-Tibet Plateau (QTP) is investigated in this paper. The results show that the glacial loss rates of glaciers in the QTP are significantly correlated with the interannual changes of precipitation and low cloud cover. The water vapor, importing with the warm and wet airflows from the Asian Monsoon regions, significantly influence the precipitation in the southern and northern glacier areas of the QTP in the summer monsoon season. The three-dimensional changes of water vapor transport can lead to the difference of water balance between different glacier areas. Under global warming, the northwest QTP is in the ascending branch of the vertical water driven thermally by the tropical Indian Ocean. The warm water vapor from the tropical ocean climbs to the QTP, forming a significant supply effect of precipitation in the northwestern glacier area, which makes the glacier retreat at a relatively slow rate. Meanwhile, the southern and southeastern QTP regions are in the descending branch of vapor transport with the declining trend in the lower troposphere, which lead to the shortage water supply aggravating the glacier loss in the southern and southeastern QTP.

Globally elevated chemical weathering rates beneath glaciers.

Physical erosion and chemical weathering rates beneath glaciers are expected to increase in a warming climate with enhanced melting but are poorly constrained. We present a global dataset of cations in meltwaters of 77 glaciers, including new data from 19 Asian glaciers. Our study shows that contemporary cation denudation rates (CDRs) beneath glaciers (2174 ± 977 Σ*meq+ m-2 year-1) are ~3 times higher than two decades ago, up to 10 times higher than ice sheet catchments (~150-2000 Σ*meq+ m-2 year-1), up to 50 times higher than whole ice sheet means (~30-45 Σ*meq+ m-2 year-1) and ~4 times higher than major non-glacial riverine means (~500 Σ*meq+ m-2 year-1). Glacial CDRs are positively correlated with air temperature, suggesting glacial chemical weathering yields are likely to increase in future. Our findings highlight that chemical weathering beneath glaciers is more intense than many other terrestrial systems and may become increasingly important for regional biogeochemical cycles.

Eco-efficiency in China's Loess Plateau Region and its influencing factors: a data envelopment analysis from both static and dynamic perspectives.

China's Loess Plateau Region (LPR) plays a significant role in national ecological security and development. Due to the advantage that relates environment with economy, eco-efficiency has become an important indicator of sustainable analysis. Using cross-level panel data for the period 2006-2017, this paper studied LPR's static eco-efficiency and dynamic performance through a combined application of DEA super-efficient slack-based measure and Malmquist Productivity Index at multi-scales. LPR's eco-efficiency was found to experience a slight increase during the study period. The value decreased roughly from east to west, with high eco-efficiency mainly distributed in provincial cities and resource-based cities. The decomposition of the Malmquist Index indicated that technological change contributed most to the improvement of eco-efficiency in the LPR. Besides, this paper explained the variations of eco-efficiency based on the integrated input-output indicators and TOBIT regression model. Economic scale, population density, government regulation, technical innovation, and openness degree were identified as positive influencing factors, while the structure of the industry and land-use intensity were found to have negative impacts on eco-efficiency. Resource-based cities were found to have stronger potentials for eco-efficiency improvement than non-resource-based cities. This paper revealed the characteristics of LPR's eco-efficiency from three perspectives: a spatiotemporal perspective, a macro-meso-micro perspective, and a static-dynamic perspective. The findings of this study hold important implications for policy makers.

Linking genomic and physiological characteristics of psychrophilic Arthrobacter to metagenomic data to explain global environmental distribution.

BACKGROUND: Microorganisms drive critical global biogeochemical cycles and dominate the biomass in Earth's expansive cold biosphere. Determining the genomic traits that enable psychrophiles to grow in cold environments informs about their physiology and adaptive responses. However, defining important genomic traits of psychrophiles has proven difficult, with the ability to extrapolate genomic knowledge to environmental relevance proving even more difficult. RESULTS: Here we examined the bacterial genus Arthrobacter and, assisted by genome sequences of new Tibetan Plateau isolates, defined a new clade, Group C, that represents isolates from polar and alpine environments. Group C had a superior ability to grow at -1°C and possessed genome G+C content, amino acid composition, predicted protein stability, and functional capacities (e.g., sulfur metabolism and mycothiol biosynthesis) that distinguished it from non-polar or alpine Group A Arthrobacter. Interrogation of nearly 1000 metagenomes identified an over-representation of Group C in Canadian permafrost communities from a simulated spring-thaw experiment, indicative of niche adaptation, and an under-representation of Group A in all polar and alpine samples, indicative of a general response to environmental temperature. CONCLUSION: The findings illustrate a capacity to define genomic markers of specific taxa that potentially have value for environmental monitoring of cold environments, including environmental change arising from anthropogenic impact. More broadly, the study illustrates the challenges involved in extrapolating from genomic and physiological data to an environmental setting. Video Abstract.

Genomic Insights of Cryobacterium Isolated From Ice Core Reveal Genome Dynamics for Adaptation in Glacier.

Glacier is the dominant cold habitat in terrestrial environments, providing a model ecosystem to explore extremophilic strategies and study early lives on Earth. The dominant form of life in glaciers is bacteria. However, little is known about past evolutionary processes that bacteria underwent during adaptation to the cryosphere and the connection of their genomic traits to environmental stressors. Aiming to test the hypothesis that bacterial genomic content and dynamics are driven by glacial environmental stressors, we compared genomes of 21 psychrophilic Cryobacterium strains, including 14 that we isolated from three Tibetan ice cores, to their mesophilic counterparts from the same family Microbacteriaceae of Actinobacteria. The results show that psychrophilic Cryobacterium underwent more dynamic changes in genome content, and their genomes have a significantly higher number of genes involved in stress response, motility, and chemotaxis than their mesophilic counterparts (P < 0.05). The phylogenetic birth-and-death model imposed on the phylogenomic tree indicates a vast surge in recent common ancestor of psychrophilic Cryobacterium (gained the greatest number of genes by 1,168) after the division of the mesophilic strain Cryobacterium mesophilum. The expansion in genome content brought in key genes primarily of the categories "cofactors, vitamins, prosthetic groups, pigments," "monosaccharides metabolism," and "membrane transport." The amino acid substitution rates of psychrophilic Cryobacterium strains are two orders of magnitude lower than those in mesophilic strains. However, no significantly higher number of cold shock genes was found in psychrophilic Cryobacterium strains, indicating that multi-copy is not a key factor for cold adaptation in the family Microbacteriaceae, although cold shock genes are indispensable for psychrophiles. Extensive gene acquisition and low amino acid substitution rate might be the strategies of psychrophilic Cryobacterium to resist low temperature, oligotrophy, and high UV radiation on glaciers. The exploration of genome evolution and survival strategies of psychrophilic Cryobacterium deepens our understanding of bacterial cold adaptation.

Black carbon deposited in Hariqin Glacier of the Central Tibetan Plateau record changes in the emission from Eurasia.

Black carbon (BC), by the combustion of fossil fuels and biomass, has profound effects on climate change and glacier retreat in industrial eras. In the present study, we report refractory BC (rBC) in an ice core spanning 1850-2014, retrieved from the Hariqin Glacier of the Tanggula Mountains in the central Tibetan Plateau, measured using a single particle soot photometer (SP2). The rBC concentration shows a three-fold increase since the 1950s. The mean rBC concentration was 0.71 ± 0.52 ng mL-1 during 1850s-1940s and 2.11 ± 1.60 ng mL-1 during 1950s-2010s. The substantial increase in rBC since the 1950s is consistent with rBC ice core records from the Tibetan Plateau and Eastern Europe. According to the predominant atmospheric circulation patterns over the glacier and timing of changes in regional emissions, the post-1950 amplification of rBC concentration in the central Tibetan Plateau most likely reflects increases in emissions in Eastern Europe, former USSR, the Middle East, and South Asia. Despite the low-level background rBC concentrations in the ice cores from the Tibetan Plateau, the present study highlights a remarkable increase in anthropogenic BC emissions in recent decades and the consequent influence on glaciers in the Tibetan Plateau.

Haloactinobacterium glacieicola sp. nov., isolated from an ice core.

A Gram-stain-positive, rod-shaped and motile bacterium with lateral flagellum, designated T3246-1T, was isolated from an ice core, which was drilled from Hariqin Glacier on the Tibetan Plateau, PR China. It grew optimally at 20 °C, pH 7-8 and in the presence of 3 % (w/v) NaCl. The major fatty acid of strain T3246-1T was anteiso-C15 : 0. Major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol. MK-8 was the dominant isoprenoid quinone. The whole-cell sugars were rhamnose, xylose and mannose. The major cell-wall peptidoglycan was lysine. The genomic DNA G+C content of the strain was 71.4 mol%. Results of phylogenetic analysis based on 16S rRNA gene sequences showed that strain T3246-1T formed a lineage within the genus Haloactinobacterium and was closely related to Haloactinobacterium album YIM 93306T with 95.99 % similarity. The average nucleotide identity value between strain T3246-1T and Haloactinobacterium album YIM 93306T was 76.65 %. Based on phenotypic and chemotaxonomic characteristics, strain T3246-1T was considered to represent a novel species of the genus Haloactinobacterium, for which the name Haloactinobacterium glacieicola sp. nov. is proposed. The type strain is T3246-1T (=CGMCC 1.13535T=JCM 32923T).