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Potash, also known as potassium (K), is a crucial component of the agricultural sector and serve as "the food of food". Historically, the formation of potash deposits has been attributed to the "tectonic-climatic" theory, in which the role of prolonged arid climate is still debating. Consider the minerogenetic time scale, paleoclimatic events may have played an undeniable role in the formation of potash. However, few studies have been conducted on this topic, which may impede theoretical development. The Lop Nur playa of the Tarim Basin, Northwest China, is a typical hinterland salt lake that formed during the combined effect of the collision between the Eurasian Plate and the Indian Plate and the Quaternary climatic background. As a potash metallogenetic area, Lop Nur is the best place to study how paleoclimatic events affect salt mineralization. In this study, we summarize the development of paleoclimate records and multiple ages from Quaternary sediments and analyze the mineralization theory of the Lop Nur salt lake. The comprehensive chronicle framework employed in paleoenvironmental reconstruction has unveiled the fluctuating aridity and the subsequent process of playa formation. By integrating mineralization mechanisms, ranging from the "mountain-basin transfer" theory to the "tectonic-climatic-source coupled" theory, we systematically reviewed the potential impacts of paleoclimatic events as both impetuses and limitations in the formation of potash deposits in Lop Nur. From a more prospective aspect of this review, the paleoclimatic events for potash mineralization are examined in relation to the worldwide distribution of salt lakes. This examination takes into account the lacustrine paleo-proxies and potash types, which indicate similar paleoclimatic influences on the mineralization process, albeit with varying origins. In the future, a more comprehensive understanding of potassium salt resources can be achieved through a thorough comparison of reconstructed paleoenvironments and high-resolution regional mineralization modeling results. [ABSTRACT FROM AUTHOR]

The bedrock weathered crust in front of the Altun Mountains in the Qaidam Basin, western China, is different from others because this is a salt‐lake basin, where saline water fluid infiltrates and is deposited in the overlying strata. A large amount of gypsum infills the bedrock weathered crust, and this has changed the pore structure. Using core observation, polarized light microscopy, electron probe, physical property analysis and field emission scanning electron microscopy experiments, the characteristics of the weathered bedrock have been studied. There are cracks and a small number of dissolved pores in the interior of the weathered crust. Matrix micropores are widely developed, especially the various matrix cracks formed by tectonics and weathering, as well as the stress characteristics of small dissolved pores, and physical properties such as porosity and permeability. This 'dual structure' developed in the bedrock is important for guiding the exploration of the lake basin bedrock for natural gas. [ABSTRACT FROM AUTHOR]

An actinomycete strain, designated YIM 98757T, was isolated from the hypersaline sediment of Aiding Lake in Xinjiang province, north-west China. The strain grew well on most media tested and no diffusible pigment was produced. The substrate mycelium was well developed and fragmented. No spores were formed. The whole-cell hydrolysates contained meso-diaminopimelic acid as the cell-wall diamino acid. Xylose, galactose, ribose were the major whole-cell sugars. The phospholipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides and an unknown phospholipid. The predominant menaquinone was MK-8(H4). The major fatty acid was iso-C16:0. The DNA G + C content was 69.1 mol%. Phylogenetic analysis indicated that the isolate belongs to the genus Haloechinothrix. However, it differed from its closest relative, H. alba YIM 98757 T in many phenotypic and chemotaxonomic characteristics. Moreover, the DNA–DNA and ANI relatedness values between the novel isolate and H. alba YIM 93221 T were 53.3% and 92.5%, respectively. Based on comparative analysis of polyphasic taxonomic data, strain YIM 98757 T represents a novel species of the genus Haloechinothrix, for which the name Haloechinothrix aidingensis sp. nov. is proposed. The type strain is YIM 98757T (= CGMCC 4.7627T = CCTCC AA 2020012). [ABSTRACT FROM AUTHOR]

A bacterial strain, designated YIM 98839T, was isolated from the hypersaline sediment of Aiding Lake in Xinjiang province, North-West China. The strain was Gram-stain-positive, motile, aerobic, produced oval subterminal or central endospores in swollen sporangia. The whole-cell hydrolysates contain meso-diaminopimelic acid as the diagnostic cell-wall diamino acid. Galactose, fucose and ribose are the major whole-cell sugars. The phospholipids are diphosphatidylglycerol, phosphatidylglycerol and one unknown phospholipid. The predominant menaquinone is MK-7. The major fatty acids are anteiso-C15:0, anteiso-C17:0 and iso-C15:0. The DNA G + C content of the type strain is 37.0 mol%. Phylogenetic analysis indicated that the isolate belongs to the genus Oceanobacillus. However, it differed from its closest relative, Oceanobacillus limi H9BT in many physiological characteristics. Moreover, the DNA–DNA relatedness values between the novel isolate and the relative type strain was 20.2%. Based on comparative analysis of polyphasic taxonomic data, strain YIM 98839T represents a novel species of the genus Oceanobacillus, for which the name Oceanobacillus halotolerans sp. nov. is proposed. The type strain is YIM 98839T (= CGMCC 1.17002T = KCTC 43140T). [ABSTRACT FROM AUTHOR]

The Paleocene sedimentary sequence in the Jiangling Depression was deposited in a salt lake environment. Based on detailed core observation of four drillholes in the Jiangling Depression, a study of sedimentary characteristics of glauberite in Paleocene lacustrine deposits was conducted through thin section petrography, X-ray diffraction, scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). This study has revealed five types of geological occurrences and six types of profile distribution features of glauberite. On the basis of petrological and mineralogical characteristics, we propose that the glauberite is mainly formed by crystallization from saturated sulfate solution and by ion exchange between sulfate solution and calcium-bearing pore solution. Glauberite mainly occurs in the late stage of Paleocene, when brine is relatively highly concentrated. Replacement of gypsum by glauberite is subordinate. The depositional model of glauberite is also discussed. The sulphur isotopic values (δ34S) and the strontium ratios (87Sr/86Sr) of the sulphate suggest a non-marine brine supply. The profile distribution features of glauberite contribute to a better understanding of the past climate change. The glauberite in Late Paleocene is frequently interbedded with dolomite, anhydrite, halite or thenardite, suggesting fluctuation of lake water salinity and climate. Trace element compositions of the mudstones imply the reducing condition and fluctuating salinity. The Homogenization temperatures and hydrogen and oxygen isotopic values (δDSMOW and δ18OSMOW) in halite and thenardite inclusions further indicate that in Paleocene the temperature was relatively high and fluctuant. Moreover, the palaeoclimate was drier in the late stage of Late Paleocene, though the temperature was cooler/lower. [ABSTRACT FROM AUTHOR]

Four halophilic archaea strains, AD-4 T , CGA30 T , CGA73 T , and WLHSJ27 T , were isolated from a salt lake and two soda lakes located in different regions of China. The 16S rRNA and rpoB' gene sequence similarities among strains AD-4 T , CGA30 T , CGA73 T , WLHSJ27 T , and the current species of the family Natrialbaceae were 90.9-97.5% and 83.1-91.8%, respectively. The phylogenetic and phylogenomic analyses revealed that these four strains separated from existing genera in the family Natrialbaceae and formed distant branches. The ANI, isDDH, and AAI values among these four strains and the current members of the family Natrialbaceae were 72-79%, 20-25%, and 63-73%, respectively, much lower than the threshold values for species demarcation. Strains AD-4 T , CGA73 T , and WLHSJ27 T may represent three novel genera of the family Natrialbaceae according to the cutoff value of AAI (≤ 76%) proposed to differentiate genera within the family Natrialbaceae. These four strains could be distinguished from the related genera according to differential phenotypic characteristics. The major phospholipids of these four strains were identical while their glycolipid profiles were diverse. DGD-1 is a major glycolipid found in strain AD-4 T , trace glycolipids, DGD-1, and S-DGD-1, and (or) S-TGD-1 was found in the other three strains. The major respiratory quinones detected in the four strains were menaquinone MK-8 and MK-8(H 2 ). This polyphasic classification indicated that strains AD-4 T , CGA73 T , and WLHSJ27 T represent three novel species of three new genera with the family Natrialbaceae, and strain CGA30 T represents a novel species of Halovivax., (© 2023. The Author(s), under exclusive licence to Springer Nature Japan KK, part of Springer Nature.)

Artemia (brine shrimp) are a widely distributed zooplankton in inland salt lakes and artificial ponds throughout the tropical, subtropical, and temperate zones. Notably, they are of great importance to fishery production and salt lake ecosystem health. Recently, Artemia resources have been threatened by habitat deterioration and overfishing, which mandate adequate monitoring; however, advanced methods for detecting Artemia from remote sensing images have rarely been discussed. Accordingly, this study explored the possibility of detecting the adult Artemia (Artemia) slicks using multispectral optical sensors by analyzing their unique aggregation patterns and consistent optical properties. After measuring Artemia spectra in the field, reflectance troughs were observed at ∼431 nm and ∼ 560 nm, which were deemed likely related to the absorption of β-carotene and heme, respectively, resulting in their reddish color. These characteristics could also be used to differentiate Artemia from other confounding features, including clean water and chlorophyll-a (Chl-a)- or suspended particulate matter (SPM)- dominated water. Based on these spectral signatures, a brine shrimp index (BSI) was developed using the difference between the reflectance at NIR band and a linear baseline between green and SWIR1 bands of Landsat-8 Operational Land Imager (OLI) imagery. Further, a BSI-based Artemia slick pixel extraction method was proposed. Using observation geometry information in conjunction with the BSI value of entire lakes, the BSI thresholds for the Artemia-containing pixels were automatically determined, and > 80% overall accuracy was achieved. The index performance was affected by the presence of residual cloud shadows, high water turbidity, and mixed pixels with low Artemia density. Moreover, BSI values were found to be relatively insensitive to atmospheric signals. It was shown here that the BSI detection limit was >0.53% Artemia subpixel coverage under clean water conditions; whereas a higher coverage was required to separate Artemia from Chl-a- or SPM- dominated water. The mean absolute percentage difference of BSI values calculated from Rayleigh-corrected and top-of-atmosphere (TOA) reflectance was <4% compared with surface reflectance derived BSI, and the relative difference in coverage area was < ±10%. Lastly, time series analyses of Lake Aibi in northwest China and the Great Salt Lake in North America revealed that the annual areal coverage estimation of Artemia slicks based on BSI was a positive indicator of Artemia harvesting, which can facilitate the Artemia resource management. • Reflectance of floating Artemia under different densities is presented and analyzed. • A novel brine shrimp index (BSI) is developed to detect Artemia slicks using Landsat imagery. • BSI shows low sensitivity to sensor noise and atmospheric signals. • BSI is also found to have the potential of Artemia biomass/harvest estimation. [ABSTRACT FROM AUTHOR]

Two novel halophilic archaeal strains, Gai3-17 T and XZYJT26 T , were isolated from the sediment of Gaize salt lake and the saline soil of Mangkang ancient solar saltern in Tibet, PR China, respectively. Strains Gai3-17 T and XZYJT26 T were related to each other (96.5 and 89.7% similarity, respectively) and showed 97.5-95.4 and 91.5-87.7% similarities to the current members of Halobacterium based on 16S rRNA and rpoB' genes. The phylogenomic analysis indicated that strains Gai3-17 T and XZYJT26 T formed two distinct clades and clustered with the Halobacterium species. The two strains can be differentiated from the type strains of the six species with validly published names based on several phenotypic characteristics. The phospholipids of the two strains were phosphatidic acid, phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. One major glycolipid, sulphated galactosyl mannosyl glucosyl diether, was detected in strain Gai3-17 T , while four glycolipids, mannosyl glucosyl diether, sulphated mannosyl glucosyl diether, disulphated mannosyl glucosyl diether and sulphated galactosyl mannosyl glucosyl diether were observed in strain XZYJT26 T . The average nucleotide identity, digital DNA-DNA hybridization and amino acid identity values among the two strains and the members of Halobacterium were no more than 81, 25 and 77 %, respectively. These overall genome-related indices were below the threshold values for species boundary, indicating that strains Gai3-17 T and XZYJT26 T represent two novel species of Halobacterium . Thus, two novel species, Halobacterium wangiae sp. nov. and Halobacterium zhouii sp. nov., are proposed to accommodate strains Gai3-17 T (=CGMCC 1.16101 T =JCM 33551 T ) and XZYJT26 T (=CGMCC 1.16682 T =JCM 33556 T ), respectively.

Five aerobic, Gram-stain-negative, non-motile, non-spore-forming, short rod bacteria strains, designated as C3-1-R+6 T , C3-2-M9, B3-2-R-7, B3-2-R-21 and C3-2-M2, were isolated from shore soil of LungmuCo Lake in Tibet of China. The 16S rRNA gene sequence comparisons confirmed their affiliation to the genus Parapedobacter of the family Sphingobacteriaceae , and showed that they were most closely related to Parapedobacter lycopersici KACC 18788 T with 94.26 % similarities. The average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values between them and the validly published Parapedobacter species were all below the thresholds for delineating species, supporting that they were novel species of genus Parapedobacter . The ANI, AAI and dDDH values between strains C3-1-R+6 T and Parapedobacter lycopersici KACC 18788 T were 72, 75, and 18% respectively. Meanwhile, the ANI/AAI and dDDH values between these five isolates were higher than the threshold values, showing that they belonged to the same species of Parapedobacter . According to genome comparison, the novel isolates have some special biosynthetic gene clusters of secondary metabolites including bacteriton, aryl-polyene, lantipeptide and t1pks, which were absent from their most related phylogenetic neighbours P. lycopersici KACC 18788 T and P. pyrenivorans CGMCC 1.12195 T . The main polar lipids contained phosphatidylethanolamine, one unidentified phospholipid, one unidentified aminolipid, one unidentified glycolipid and five unidentified lipids. The predominant respiratory quinone was MK-7. The major cellular fatty acids were iso-C 15 : 0 , summed feature 3 (C 16 : 1  ω 7 c and/or C 16 : 1  ω 6 c ) and iso-C 17 : 0 3-OH. The genome size of strain C3-1-R+6 T was 5 984 948 bp, and its genomic DNA G+C content was 46.21 mol%. To sum up, the five strains were identified as a novel species of the genus Parapedobacter , for which the name Parapedobacter tibetensis sp. nov. was proposed. The type strain was C3-1-R+6 T (=CGMCC 1.19194 T =KCTC 92150 T ).

Chemical analysis was performed on sediment core samples collected from three salt lakes, Amara Lake, Caineni Lake, and Movila Miresii Lake, located in the northeast of the Romanian Plain. The concentration of 10 main elements, 6 heavy metals (HMs), 8 rare earth elements (REEs), and 10 trace elements (TEs)-determined using neutron activation analysis (NAA)-showed variability dependent on the depth sections, lake genesis and geochemical characteristics (oxbow, fluvial harbor/liman and loess saucer type). The assessment of pollution indices (contamination factor, pollution load index, geoaccumulation index, and enrichment factor) highlighted low and moderate degrees of contamination for most of the investigated elements. Principal component analysis (PCA) extracted three principal components, explaining 70.33% (Amara Lake), 79.92% (Caineni Lake), and 71.42% (Movila Miresii Lake) of the observed variability. The principal components extracted were assigned to pedological contribution (37.42%-Amara Lake, 55.88%-Caineni Lake, and 15.31%-Movila Miresii Lake), salts depositions (due to the lack of a constant supply of freshwater and through evaporation during dry periods), atmospheric deposition (19.19%-Amara Lake, 13.80%-Caineni Lake, and 10.80%-Movila Miresii Lake), leaching from soil surface/denudation, rock weathering, and mixed anthropogenic input (e.g., agricultural runoff, wastewater discharges) (13.72%-Amara Lake, 10.24%-Caineni Lake, and 45.31%-Movila Miresii Lake).

[Display omitted] • The pollen record since mid-MIS 3 was provided for a current-hyperarid region of China. • The climate was subhumid during the mid-late MIS 3 and hyperarid during the Holocene. • Insolation and ice volume were the forcing mechanisms for climate changes in the Jilantai Basin. The climate conditions of the marginal region of the Asian summer monsoon (ASM) domain during Marine isotope stage (MIS) 3 (60–27 cal kyr BP) are poorly understood and require further study. Here, we collected fossil pollen samples from a 24.0-m-long drill core from Jilantai Salt Lake (Inner Mongolia, China) to reconstruct the regional climate changes since mid-MIS 3. During 47.0–43.0 cal kyr BP, the frequencies of the occurrence of aquatics and Pediastrum indicate relatively humid conditions. At approximately 43.0 cal kyr BP, the climate became dry, as revealed by the increase in Ephedra and the reduced aquatics and Pediastrum concentrations. The climate during 43.0–27.1 cal kyr BP was drier than that in the previous interval. Aquatics, ferns, and algae were barely detectable, indicating harsh climate conditions during 27.1–12.2 cal kyr BP. During the Holocene, aquatics and algae vanished, and the observed pollen assemblages were dominated by herb taxa; however, a substantial loss of taxa numbers occurred, suggesting that the climate was hyperarid. In general, the climate was relatively humid during the mid-late MIS 3, arid during MIS 2 (27.0–11.7 cal kyr BP), and hyperarid during the Holocene. The evaporation capacity connected with the Northern Hemisphere summer insolation and the Northern Hemisphere ice volume may have played a vital role in vegetation and climate changes in the Jilantai Basin since mid-MIS 3. [ABSTRACT FROM AUTHOR]

Six novel halophilic archaeal strains of XZYJT10 T , XZYJ18 T , XZYJT40 T , XZYJT49 T , YCN54 T and LT46 T were isolated from a solar saltern in Tibet, a salt lake in Shanxi, and a saline soil in Xinjiang, China. Sequence similarities of 16S rRNA and rpoB' genes among strains XZYJT10 T , XZYJ18 T , XZYJT40 T , XZYJT49 T , YCN54 T , LT46 T and current members of Halorussus were 90.6-97.8% and 87.8-96.4%, respectively. The average nucleotide identity and in silico DNA-DNA hybridization values among these six strains and current Halorussus members were in the range of 76.5-87.5% and 21.0-33.8%, respectively. These values were all below the species boundary threshold values. The phylogenomic tree based on 122 conserved archaeal protein marker genes revealed that the six novel strains formed individual distinct branches and clustered tightly with Halorussus members. Several phenotypic characteristics distinguished the six strains from current Halorussus members. Polar lipid analysis showed that the six novel strains contained phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and two to three glycolipids. Phenotypic, chemotaxonomic and phylogenetic properties showed that the six strains represented six novel species within the genus Halorussus, for which the names Halorussus vallis sp. nov., Halorussus aquaticus sp. nov., Halorussus gelatinilyticus sp. nov., Halorussus limi sp. nov., Halorussus salilacus sp. nov., and Halorussus salinisoli sp. nov. are proposed., (© 2022. The Author(s), under exclusive licence to Springer Japan KK, part of Springer Nature.)

A halotolerant actinomycete strain, designated XHU 5031, was isolated from a salt lake in Xinjiang Province, northwest China. Its taxonomic status was determined using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the organism was most closely related to Myceligenerans xiligouense DSM 15700 (98.4 %), Myceligenerans halotolerans XJEEM 11063 (98.0 %) and Myceligenerans crystallogenes DSM 17134 (97.5 %). However, it had relatively low values for DNA-DNA relatedness with the above strains (46.2, 39.4 and 36.5 %, respectively). The peptidoglycan type was A4α. This organism contained glucose, mannose and galactose as the major whole cell sugars. The predominant menaquinone was MK-9(H). The major fatty acids were iso-C anteiso-C and iso-C. The polar lipids detected were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylinositol (PI), one unknown phospholipid (PL) and two unknown glycolipids (GL). The G+C content of genomic DNA was 71.2 mol %. Phenotypic data clearly distinguished the isolate from its closest relatives. The combined genotypic and phenotypic data indicated that the isolate XHU 5031 represented a novel species of the genus Myceligenerans. The proposed name for this organism is Myceligenerans salitolerans sp. nov., with type strain XHU 5031 (=KCTC 29128 = CCTCC AB 2012908). [ABSTRACT FROM AUTHOR]

Abstract: Some rivers on the northern slope of the eastern Kunlun Mountains in the Qaidam Basin, China, show very high concentrations of boron and lithium. Correspondingly, the salt lakes fed by these rivers show an unusual enrichment of boron and lithium, and become an important economic resource. The origin of boron and lithium has long been debated. The aim of this study is to analyze the water chemistry and hydrogen and oxygen isotopic composition of river water to understand the unusual enrichment of boron and lithium in the salt lakes of the Qaidam Basin. Oxygen and hydrogen isotope data show that the source of river water in the winter and summer originates from the Kunlun Mountain ice and snow melt water, respectively. The water chemistry shows that boron and lithium contents are high but little variable with seasons in the Nalenggele River and Wutumeiren River waters. By contrast, other rivers have much lower lithium and boron contents. Moreover, the contents of B3+ and Li+ in the river loads or bed sands show little difference amongst the rivers. This indicates that removal by adsorption or input by surface rock weathering is not the main controlling factor of the B3+ and Li+ variation in the rivers. Rivers with high B3+ and Li+ content are chemically similar to geothermal waters in the Tibetan Plateau. In addition, the source area of the Nalenggele River is located in a collision zone of the Kunlun Mountains and Altun Mountains. Large and deep faults can serve as conduits for geothermal fluids. Thus, deep geothermal waters in the source area can easily migrate to the surface and discharge as springs feeding the rivers. They are an important source of B3+ and Li+ to the rivers. The abnormally high contents of B3+ and Li+ in the Nalenggele and Wutumeiren Rivers also suggest that the geothermal source area may be a future target for boron and lithium resources. [Copyright &y& Elsevier]

novel actinomycete strain, designated TRM 40133, was isolated from a hypersaline habitat of Tarim basin in Xinjiang Province, north-west China. Its taxonomic status was determined using a polyphasic approach. Phylogenetic analysis based on an almost-complete 16S rRNA gene sequence of the strain showed that it formed a well-seperated sub-branch within the radiation of the genus Saccharopolyspora. The highest levels of 16S rRNA gene sequence similarity was found between the strain TRM 40133 and Saccharopolyspora qijiaojingensis YIM 91168 (96.5%). The chemotaxonomic characteristics of the isolate are typical for the genus Saccharopolyspora. It contained meso-DAP as the diagnostic diamino acid. Whole cell hydrolysate contained arabinose, xylose, ribose and glucose. The diagnostic phospholipids were phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol and two unknown phospholipids. The main menaquinone was MK-9(H) and MK-9(H). No mycolic acid was detected. The predominant cellular fatty acids were iso-C and anteiso-C. The G+C content of the genomic DNA was 68.2 mol%. In addition, the strain TRM 40133 had a phenotypic profile that readily distinguished it from the recognized representatives of the genus Saccharopolyspora. The strain TRM 40133 therefore represents a novel species of the genus Saccharopolyspora, for which the name Saccharopolyspora lacisalsi sp. nov. is proposed. The type strain is TRM 40133 (=KCTC 19987 =CCTCC AA 2010012). [ABSTRACT FROM AUTHOR]

A novel Gram-negative, slightly halophilic, catalase- and oxidase-positive, obligately aerobic bacterium, strain YIM-C248T, was isolated from a sediment sample collected from a salt-lake in the Qaidam Basin in Qinghai, north-west China. Cells were non-sporulating short rods, occurring singly or as doublets, motile with peritrichous flagella. Growth occurred with 1–15% (w/v) NaCl [optimum 2–4% (w/v) NaCl], at pH 6.0–10.0 (optimum pH 7.5) and at 4–35°C (optimum 25–30°C). The major cellular fatty acids were C18:1 ω7 c, C12:0 3-OH, cyclo C19:0 ω8 c, C16:0 and C16:1. The predominant respiratory quinone was Q-9 and the genomic DNA G + C content was 58.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YIM-C248T should be assigned to the genus Halomonas. The sequence similarities between the isolate and the type strains of members of the genus Halomonas were in the range of 92.5–97.5%. The combination of phylogenetic analysis, DNA–DNA hybridization data, phenotypic characteristics and chemotaxonomic differences supported the view that strain YIM-C248T represents a new species of the genus Halomonas, for which the name Halomonas sediminis sp. nov. is proposed, with YIM-C248T (=CCTCC AA 207031 = KCTC 22167) as the type strain. [ABSTRACT FROM AUTHOR]

Abstract: A motile, Gram-positive, slightly halophilic, endospore-forming, catalase- and oxidase-positive, obligately aerobic, slender rod-shaped bacterium, strain YIM-C229T was isolated from the sediment of a salt lake in the Qaidam Basin, north-west China. Filamentous forms were present throughout the growth cycle. Strain YIM-C229T grew in the presence of 0.5–8% NaCl and at pH 6.0–8.5, with optimum growth at 1–3% NaCl and pH 7.0–7.5. It grew at 4–45°C, with optimum growth at 37°C. The major cellular fatty acids were anteiso-C15:0, C16:0, iso-C15:0, C16:1 ω11c and anteiso-C17:0. The predominant respiratory quinone was MK-7, and diphosphatidylglycerol and phosphatidylglycerol were the polar lipids, with meso-diaminopimelic acid occurring in the cell-wall peptidoglycan. The genomic DNA G+C content was 40.9mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM-C229T was closely related to the type strains of the four recognized species of the genus Gracilibacillus: G. halotolerans NNT (sequence similarity 95.5%), G. dipsosauri DD1T (96.1%), G. orientalis XH-63T (96.8%) and G. boraciitolerans T-16XT (99.1%). The DNA–DNA relatedness between strain YIM-C229T and G. boraciitolerans DSM 17256T was 30.8%. The combination of phylogenetic analysis, phenotypic characteristics, chemotaxonomic differences and DNA–DNA hybridization data supported the view that this strain represented a novel species of the genus Gracilibacillus, for which the name Gracilibacillus quinghaiensis sp. nov. is proposed, with YIM-C229T (=DSM 17858T=CGMCC 1.6304T) as the type strain. [Copyright &y& Elsevier]

Long-term intake of high-fluoride groundwater causes endemic fluorosis. This study, for the first time, discovered that the salt lake water intrusion into neighboring shallow aquifers might result in elevation of fluoride content of the groundwater. Two cross-sections along the groundwater flow paths were selected to study the geochemical processes controlling fluoride concentration in Yuncheng basin, northern China. There are two major reasons for the observed elevation of fluoride content: one is the direct contribution of the saline water; the other is the undersaturation of the groundwater with respect to fluorite due to salt water intrusion, which appears to be more important reason. The processes of the fluorine activity reduction and the change of Na/Ca ratio in groundwater induced by the intrusion of saline water favor further dissolution of fluorine-bearing mineral, and it was modeled using PHREEQC. With the increase in Na concentration (by adding NaCl or Na2SO4 as Na source, calcium content kept invariable), the increase of NaF concentration was rapid at first and then became slower; and the concentrations of HF, HF, CaF+, and MgF+ were continuously decreasing. The geochemical conditions in the study area are advantageous to the complexation of F− with Na+ and the decline of saturation index of CaF2, regardless of the water type (Cl–Na or SO4–Na type water). [ABSTRACT FROM AUTHOR]

The article presents abstracts of several studies on environmental geochemistry. Some of the abstracts presented include "Biogeochemical Cycling of Nutrients in Karstic Catchments, Southwestern China: Linkages to Changes of Eco-Environments," by Congqiang Liu and "Emerging Organic Contamination in China," by Guibin Jiang and colleagues.

Potassium-rich halite ores and brines occur in the Charham Salt Lake area in the Chaidam Basin in northwest China. The mean 14.3 g/l of potassium in the brines in the near-surface halite aquifer makes the Charham Salt Lake an important base for production of potassium fertilizer in China. About 30×104 m3/day of brines has been pumped from the current ditches in the Bieletan section in the west of the area, creating a cone of depression in the water table near the ditch system. A two-dimensional mathematic model describing the flow of the brines is established to predict the changes in the water table. The flow domain was discretized into 1,185 triangular elements with 641 nodes. Data of brine production through pumping ditches from November 2002 to August 2003 were used to identify the model. The developed model can be employed to predict the exploitation regimes caused by three proposed exploitation schemes A, B and C. A withdrawal rate of 22.67×104 m3/day of brines is pumped through the current ditch system in scheme A and through the current ditch system plus 16 wells in scheme B. The results of the 5 years predictive simulation for schemes A and B indicate that these rates will cause a normal fall in water table in the pumping period of 9 months and a rise in water table in the recovery period of 3 months in each of the 5 years, with one depression cone near the current ditches in scheme A and two depression cones near the current ditches and the proposed wells in scheme B. In scheme C three more ditch systems are proposed to be excavated in the northeast, northwest and southwest of the Bieletan section and brines are pumped through each of the four ditch systems in turn for 1 year in every 4 years. The predictive simulation results of scheme C suggest that normal changes in the water table will also be expected and a continual increasing or decreasing trend in the water table will not be encountered in a 12-year period of prediction. The water table near each of the four ditch systems will recover sufficiently after a 39-month recovery. [ABSTRACT FROM AUTHOR]

Three halophilic archaeal strains, NEN8 T , GDY88 T and ZY14 T , were isolated from a salt lake in Tibet and coarse sea salt samples from Guangdong and Hebei, China, respectively. These strains formed three separate clades (showing 94.4-95.8% and 87.1-89.4% similarities, respectively) and then clustered with the current Halorientalis members (showing 90.7-97.6% and 87.0-91.2% similarities, respectively), as revealed by phylogenetic analyses based on 16S rRNA and rpoB' genes. The overall genome-related index, average nucleotide identity (ANI), in silico DNA-DNA hybridization (DDH), average amino acid identity (AAI) and the percentage of conserved proteins (POCP) values, among the three strains and members of the genus Halorientalis were 76.0-88.0%, 21.3-37.2%, 69.0-88.3% and 57.7-78.1%, clearly below the threshold values for species demarcation. Strains NEN8 T , GDY88 T and ZY14 T could be distinguished from current Halorientalis species according to differential phenotypic characteristics. The major polar lipids of the three strains were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), sulfated mannosyl glucosyl diether (S-DGD-1) and disulfated mannosyl glucosyl diether (S 2 -DGD). In addition, mannosyl glucosyl diether (DGD-1) was detected in strain NEN8 T and phosphatidic acid (PA), posssulfated galactosyl mannosyl glucosyl diether (S-TGD-1) and sulfated mannosyl glucosyl diether-phosphatidic acid (S-DGD-PA) were observed in strain ZY14 T . These results revealed that strains NEN8 T (= CGMCC 1.17213 T  = JCM 34155 T ), GDY88 T (= CGMCC 1.18548 T  = JCM 34481 T ) and ZY14 T (= CGMCC 1.17178 T  = JCM 34154 T ) represent three novel species of the genus Halorientalis, for which the names Halorientalis salina sp. nov., Halorientalis marina sp. nov. and Halorientalis litorea sp. nov. are proposed., (© 2022. The Author(s), under exclusive licence to Springer Japan KK, part of Springer Nature.)

Three halophilic archaeal strains, Gai1-5 T , SEDH52 T and SQT7-1 T were isolated from Gaize salt lake and Xiadi salt lake in Tibet, and saline soil from Xinjiang, respectively. Phylogenetic analysis based on 16S rRNA gene and rpoB' gene sequences showed that these three strains formed different branches separating them from Haloprofundus halophilus NK23 T (97.7-98.3% similarities for 16S rRNA gene and 94.7-94.8% similarities for rpoB' gene, respectively) and Haloprofundus marisrubri SB9 T (94.7-96.4% similarities for 16S rRNA gene and 92.3-93.2% similarities for rpoB' gene, respectively). Several phenotypic characteristics distinguish the strains Gai1-5  T , SEDH52 T and SQT7-1 T from Haloprofundus halophilus NK23 T and Haloprofundus marisrubri SB9 T . The average nucleotide identity (ANI) and in silico DNA-DNA hybridization (isDDH) values among the three strains and current Haloprofundus members were in the range of 83.3-88.3% and 27.2-35.7%, respectively, far below the species boundary threshold values. The major polar lipids of three strains were phosphatidic acid (PA), phosphatidylglycerol (PG), phosphatidylglycerol sulphate (PGS), phosphatidylglycerol phosphate methyl ester (PGP-Me), sulfated mannosyl glucosyl diether (S-DGD-1), mannosyl glucosyl diether-phosphatidic acid (DGD-PA) and sulfated mannosyl glucosyl diether-phosphatidic acid (S-DGD-PA). These results showed that strains Gai1-5 T (= CGMCC 1.16079 T  = JCM 33561 T ), SQT7-1 T (= CGMCC 1.16063 T  = JCM 33553  T ) and SEDH52 T (= CGMCC 1.17434 T ) represented three novel species in the genus Haloprofundus, for which the names Haloprofundus salilacus sp. nov., Haloprofundus salinisoli sp. nov., and Haloprofundus halobius sp. nov. are proposed., (© 2021. The Author(s), under exclusive licence to Springer Japan KK, part of Springer Nature.)

Two halophilic archaeal strains, C90 T and YPL13 T , were isolated from a salt lake and a salt mine in PR China. The two strains were found to form two clusters (97.5 and 89.5 % similarity between them, respectively) separating them from the three current members of the genus Natronomonas (95.4-97.0 % and 86.6-89.3 % similarity, respectively) on the basis of the 16S rRNA and rpoB' gene sequence similarities and phylogenetic analysis. Diverse phenotypic characteristics differentiate strains C90 T and YPL13 T from current Natronomonas members. The polar lipids of strain C90 T were phosphatidic acid, phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulphate, two unidentified glycolipids, a major glycolipid and a minor glycolipid, while those of strain YPL13 T were PG, PGP-Me, two unidentified phospholipids and a glycolipid. The average nucleotide identity (ANI) and in silico DNA-DNA hybridization ( is DDH) values between the two strains were 79.8 and 27.1 %, respectively, which were much lower than the threshold values proposed as a species boundaries (ANI 95-96 % and is DDH 70 %), which revealed that the two strains represent two novel species; these values (ANI 76.6-80.0 % and is DDH 21.6-27.0 %) of the strains examined in this study and the current members of Natronomonas are much lower than the recommended threshold values, suggesting that strains C90 T and YPL13 T represent two genomically different species of Natronomonas . These results showed that strains C90 T (=CGMCC 1.13738 T =JCM 32961 T ) and YPL13 T (=CGMCC 1.13884 T =JCM 31111 T ) represent two novel species of Natronomonas , for which the names Natronomonas halophila sp. nov. and Natronomonas salina sp. nov. are proposed.

A novel Gram-stain-negative, strictly aerobic, gliding and rod-shaped bacterial strain, designated strain C33 T , was isolated from Yuncheng Salt Lake, Shanxi, PR China. Strain C33 T grows optimally at 37 °C, pH 7.5 and 5.0 % (w/v) NaCl. Cells of strain C33 T are 0.3-0.5 µm wide and 1.0-2.0 µm long, catalase-positive and oxidase-positive. The major cellular fatty acids are iso-C 15 : 0 and iso-C 16 : 0 . The sole respiratory quinone is Q-8. The major polar lipids include phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, one unidentified aminophospholipid, one unidentified glycolipid and four unidentified lipids. The results of phylogenetic analysis based on 16S rRNA gene sequences indicate that strain C33 T has the highest similarities to Wenzhouxiangella marina KCTC 42284 T (97.4 %), Wenzhouxiangella sediminis XDB06 T (96.5 %) and ' Wenzhouxiangella salilacus ' MCCC 1K03442 T (95.2 %). The percentage of conserved proteins and average amino acid identity values between strain C33 T and its close related species are higher than the threshold for dividing genera, the average nucleotide identity and digital DNA-DNA hybridization values are well below the threshold limits for species delineation. The genomic DNA G+C content is 63.7 mol%. Based on the results of phenotypic, chemotaxonomic and phylogenetic analyses, strain C33 T is considered to represent a novel species of the genus Wenzhouxiangella , for which the name Wenzhouxiangella limi sp. nov. is proposed. The type strain is C33 T (=MCCC 1H00413 T =KCTC 72874 T ).

A bacteria strain, designated CFH 90008 T , was isolated from a salt lake sediment sample collected from Yuncheng city, Shanxi Province, PR China. Strain CFH 90008 T was Gram-stain-negative, strictly aerobic, motile with lateral flagella and rod-shaped. Colonies were yellow, circular and smooth. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain CFH 90008 T belonged to the genus Halomonas , showing highest sequence similarity to Halomonas daqingensis DQD2-30 T (98.6 %), Halomonas saliphila LCB169 T (98.5 %), Halomonas desiderata FB2 T (98.1 %) and Halomonas kenyensis AIR-2 T (98.0 %). Good growth was observed at 10-50 °C, pH 6.0-9.0 and with NaCl concentration from 1.0 to 12.0 % (w/v). The predominant quinone was Q9. The major fatty acid (>10 %) was C 18 : 1  ω7 c , C 16 : 0 and C 16 : 1  ω7 c . The genome of strain CFH 90008 T was 4.36 Mbp with a genomic DNA G+C content of 66.7 mol%. Based on low average nucleotide identity and DNA-DNAhybridization results, chemotaxonomic characteristics, and differential physiological properties, strain CFH 90008 T could not be classified into any recognized species of the genus Halomonas . Therefore, a new species, for which the name Halomonas lactosivorans sp. nov. is proposed. The type strain is CFH 90008 T (=DSM 103220 T =KCTC 52281 T ).

Salt lakes on the Qinghai-Tibetan Plateau (QTP) are remarkable for Li-rich brines. Along with the surging demand of Li, the Li-rich brines in salt lakes on the QTP are of great importance for China's Li supply. Previous studies reported the geological, geographical, geochemical signatures of numerous salt lakes on the QTP; however, conclusive work and the internal relationships among the hydrochemistry, distribution and geological setting of Li-rich salt lakes are still inadequate. In this study, major and trace (Li, B) ionic compositions of 74 Li-rich salt lakes on the QTP were reviewed. The Li-rich brines cover various hydrochemical types (carbonate, sodium sulfate, magnesium sulfate, and chloride types) and present horizontal zoning from the southwest to the northeast along with the stronger aridity. The Li concentrations and Mg/Li ratios in these salt lakes range from 23 to 2895 mg/L, 0.0 to 1549.4, respectively. The distribution of these salt lakes is close to the major suture zones. Geothermal water is proposed to be the dominant source of Li in the investigated salt lakes, while weathering of Li-bearing sediments and igneous rocks, and brine migration provide a minor part of Li. Four factors (sufficient Li sources, arid climate, endorheic basin and time) should be considered for the formation of Li-rich brines in salt lakes on the QTP. [ABSTRACT FROM AUTHOR]

A novel bacterium, XHU 5135 T , belonging to the genus Aidingimonas , was isolated from a salt lake sample collected in Xinjiang Province, north-west PR China. The isolate was Gram-stain-negative, rod-shaped and non-motile. The strain was catalase-positive and oxidase-negative. Growth occurred at NaCl concentrations of 5-25 % (optimum, 10-13 %), at 13-41 °C (35-37 °C) and at pH 6.0-10.0 (pH 7.0-8.0). The predominant ubiquinone was Q-9. The major fatty acids were C 19 : 0 cyclo ω 8 c and C 16 : 0 . The G+C content of the genomic DNA was 58.1 mol%. The affiliation of strain XHU 5135 T with the genus Aidingimonas was confirmed by 16S rRNA gene sequence comparisons. The closest type strain was Aidingimonas halophile YIM 90637 T , which showed a 16S rRNA gene sequence similarity of 97.5 %. The ANI value between XHU 5135 T and the closest type strain was 80.01 %. The estimated digital DNA-DNA hybridization estimate value between strain XHU 5135 T and the closest type strain was 22.80 %. Phenotypically, the characteristics of XHU 5135 T were shown to differ from the most closely related species, A. halophila . On the basis of the data from this polyphasic study, strain XHU 5135 T represents a novel species of the genus Aidingimonas , for which the name Aidingimonas lacisalsi sp. nov. is proposed. The type strain is strain XHU 5135 T (=CCTCC AB 2016344 T =KCTC 42945 T =DSM 104700 T ).

A Gram-stain negative, non-motile, strictly aerobic and rod-shaped bacterium, designated as 15181 T , was isolated from a salt lake in Xinjiang Province, China. Strain 15181 T was able to grow at 10-40 °C (optimum 37 °C), pH 6.0-8.5 (optimum 7.0) and with 1-14% NaCl (optimum 4%, w/v). According to phylogenetic analysis based on 16S rRNA gene sequences, strain 15181 T was assigned to the genus Wenzhouxiangella with high 16S rRNA gene sequence similarity of 97.4% to Wenzhouxiangella sediminis XDB06 T , followed by Wenzhouxiangella marina KCTC 42284 T (95.9%). Strain 15181 T exhibited ANI values of 80.0% and 72.0% to W. sediminis XDB06 T and W. marina KCTC 42284 T , respectively. The in silico DDH analysis revealed that strain 15181 T shared 19.1% and 18.7% DNA relatedness with W. sediminis XDB06 T and W. marina KCTC 42284 T , respectively. Chemotaxonomic analysis showed that the sole respiratory quinone was ubiquinone-8, the major fatty acids included iso-C 15:0 , iso-C 16:0 and summed feature 9 (C 16:0 10-methyl and/or iso-C 17:1 ω9c). The major polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified glycolipids, two unidentified phospholipids, two unidentified aminophospholipids and an unidentified lipid. On the basis of phenotypic, genotypic and chemotaxonomic characteristics presented in this study, strain 15181 T is concluded to represent a novel species in the genus Wenzhouxiangella, for which the name Wenzhouxiangella salilacus sp. nov. is proposed. The type strain is 15181 T (=KCTC 62172 T =MCCC 1K03442 T ).

The article presents a study of the preliminary measurements of boundary layer reactive halogens over salt lake in West China based on the Multi Axis-Differential Optical Absorption Spectroscopy (MAX-DOAS) technique. It mentions that the Slant Column Density (SCD) was obtained by scattered sunlight at various elevation angles. It demonstrates the first direct spectroscopic measurement of chlorine dioxide (OclO) and bromine oxides (BrO) over salt lakes in Qaidam basin.