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Two previously studied specimens of Gansurhinus qingtoushanensis are restudied, accompanied by the description of a relatively complete skeleton from the Lopingian Naobaogou Formation of Nei Mongol, China. The new skeleton represents an immature individual of a new species of Gansurhinus, which can be diagnosed by the choana position posterior to the premaxillary teeth, maxillary tooth position numbers of tooth row 5 is about half of tooth row 4, and length of row 5 is much shorter than length of tooth row 4. IVPP V12026 from the Naobaogou Formation is referred to the new species. Gansurhinus is distinguished by a diastema on the upper jaw, five rows of teeth on maxilla and dentary, teeth on the multiple tooth-rowed region bearing cusp-like emargination on the crown, lacking dental tooth wear. The following features could be the diagnostic characters of the genus or autapomorphies of the new species: ectopterygoid present; adductor fossa short relative to the length of lower jaw, with small contribution of surangular to posterolateral border; trapezoidal coronoid eminence with nearly straight dorsal margin; and foramen intermandibularis caudalis absent. Gansurhinus is more closely related to Rothianiscus than Moradisaurus, supporting previous analyses. This study further confirms recent work suggesting that the moradisaurine clade is more diverse than currently recognized. [ABSTRACT FROM AUTHOR]

Chroniosuchians were the only clade of non-amniotic reptiliomorphs that survived into the Triassic. Recent discoveries have increased their species and anatomical diversity and expanded their distribution in time and space. Most species were represented only by osteoderms, and complete or articulated remains are rare. Here we report a partial skull with a mandible and associated postcranial skeleton from the Naobaogou Formation in the Daqingshan, Nei Mongol, China. It is referred to Laosuchus based on the absence of a preorbital fenestra, the presence of a well-developed transverse flange of the pterygoid that contacts the maxilla, an internal crest on and above the dorsal side of the palate (vomer, ectopterygoid and pterygoid), a shallow otic notch formed by the tabular horn and the posterior part of the squamosal, a thin and high ventromedial ridge on the parasphenoid; the surangular dorsal surface forming a fossa for the insertion of the external adductors, the maxilla and quadratojugal separated by the jugal, and a jugal with a ventral (alary) process bordering the subtemporal fenestra. A new species, L. hun, is established based on its palatal dentition that is reduced, with but a few denticles on the vomer and pterygoid, and an irregular posterior cheek margin. Laosuchus can be referred to Chroniosuchidae based on cranial features, and the divergence of the Chroniosuchidae and Bystrowianidae is confirmed in this study. New findings reinforce the hypothesis of the migration route from North China to Laos in the late Permian. [ABSTRACT FROM AUTHOR]

Background: Although urbanization is threatening biodiversity worldwide, the increasing green urban spaces could harbor relatively high biodiversity. Therefore, how to maintain the biodiversity in urban ecosystem is crucial for sustainable urban planning and management, especially in arid and semiarid regions with relatively fragile environment and low biodiversity. Here, for the first time we linked species richness, phylogenetic and functional structure of bird assemblages in university campuses in northern China with plant species richness, glacial-interglacial climate change, contemporary climate, and anthropogenic factors to compare their relative roles in shaping urban bird diversity. Methods: Bird surveys were conducted in 20 university campuses across Inner Mongolia, China. Ordinary least squares models and simultaneous autoregressive models were used to assess the relationships between bird species richness, phylogenetic and functional structure with environmental factors. Structural equation models were used to capture the direct and indirect effects of these factors on the three components of bird diversity. Results: Single-variable simultaneous autoregressive models showed that mean annual precipitation was consistently a significant driver for bird species richness, phylogenetic and functional structure. Meanwhile, mean annual temperature and plant species richness were also significant predictors for bird species richness. Conclusions: This study suggests that campuses with warmer and wetter climate as well as more woody plant species could harbor more bird species. In addition, wetter campuses tended to sustain over-dispersed phylogenetic and functional structure. Our findings emphasize the dominant effect of precipitation on bird diversity distribution in this arid and semiarid region, even in the urban ecosystem. [ABSTRACT FROM AUTHOR]

Abstract The sorption behavior of selenite onto the Tamusu clay from a preselected high-level radioactive waste disposal site in Inner Mongolia, China, was first investigated in simulated groundwater with high salinity by batch sorption experiments under aerobic/anaerobic conditions. The results demonstrated that the K d values rapidly decreased and then remained steady in the pH range of 2.0–8.0. However, selenite sorption was promoted when pH exceeded 8.0, which might be attributed to the coprecipitation between Ca2+ and SeO 3 2−. Besides, the change trend of the K d values as functions of various parameters was not affected by oxygen. The sorption kinetics and isotherms could be well fitted by the pseudo-second-order kinetic model and the Freundlich model for both aerobic and anaerobic conditions, and the calculated thermodynamic parameters (△ G and △ H) suggested that the selenite sorption process was a spontaneous and endothermic process. Additionally, the XPS results revealed that Se(IV) could be reduced to Se (0) only in anaerobic conditions and that the different amounts of Fe on the clay surface led to the discrepancy of the Se(IV) K d values under aerobic and anaerobic conditions even in high-salt simulated groundwater. Overall, our findings in this study are significant in regards to the retardation of selenite on the host rock under high salinity conditions. Highlights • Selenite sorption was investigated in simulated groundwater with high salinity. • K d values in aerobic conditions were higher than those in anaerobic conditions. • The change trend of the K d values was not affected by oxygen. • Selenite sorption was promoted at alkaline conditions. [ABSTRACT FROM AUTHOR]

Two new tetrapod burrow casts from the Naobaogou Formation (Middle or Late Permian) of Nei Mongol, China are described. It marks the first pre-Cenozoic tetrapod burrow from China, and one of the earliest records of tetrapod burrows. Comparison to other Permian and Triassic burrows suggests that these burrows were created by tetrapod slightly smaller than Lystrosaurus. Deduced from the morphology and sizes of two burrows and known tetrapods of the Naobaogou Formation, the burrow should be the production of a therapsid, most likely a dicynodon. These burrows indicate a seasonal climate and this area was semiarid or arid during that time. [ABSTRACT FROM AUTHOR]

The large Jiawula Pb–Zn–Ag deposit is located in the Derbugan metallogenic belt of the northern Great Xing’an Range. The vein style orebodies of the deposit occur along NWW- to NNW-trending fault zones. The ore-forming process at the deposit can be divided into three stages: an early quartz–pyrite–pyrrhotite–chalcopyrite stage, a middle quartz–carbonate–pyrite–galena–sphalerite stage, and a late quartz–carbonate–pyrite stage. Sulfide Rb–Sr dating indicates that the Jiawula deposit formed at ca. 143–142 Ma. Four types of fluid inclusions have been distinguished in quartz veins including liquid-rich, gas-rich, H 2 O–CO 2 , and daughter mineral-bearing inclusions. The fluid inclusions of the early stage are mainly liquid-rich, gas-rich, and H 2 O–CO 2 types, with a small number containing daughter minerals. Cumulatively, the types have homogenization temperatures, densities, and salinities of 304–438 °C, 0.35–1.37 g/cm 3 , and 0.8–44.6 wt.% NaCl eqv., respectively. Inclusions of the middle stage are mainly liquid-rich and gas-rich types, with a small amount of H 2 O–CO 2 and daughter mineral-bearing types; their homogenization temperatures, densities, and salinities vary from 242 °C to 297 °C, 0.71 to 1.44 g/cm 3 , and 0.4 wt.% to 36.8 wt.% NaCl eqv., respectively. The late stage only comprises liquid-rich inclusions with homogenization temperatures, densities, and salinities of 181–238 °C, 0.81–0.90 g/cm 3 , and 0.2–1.9 wt.% NaCl eqv., respectively. The ore-forming fluids of the Jiawula deposit are generally characterized by moderate temperature and low salinity and density, and belong to an H 2 O–NaCl–CO 2 ± CH 4 system. The δ 18 O water values calculated for ore-bearing quartz vary from −13.4‰ to −9.1‰, and the δD V-SMOW values from bulk extraction of fluid inclusion waters vary from −166‰ to −133‰, suggesting that the ore-forming fluids mainly consist of meteoric water with a small amount of magmatic water. The δ 34 S V-CDT values range from 1.2‰ to 8.4‰. The 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, and 208 Pb/ 204 Pb values of the ore minerals are in the ranges of 18.319–18.377, 15.499–15.596, and 38.094–38.314, respectively. Initial 87 Sr/ 86 Sr ratios of sulfides range from 0.712381 to 0.712770. The data for the S, Pb, and Sr isotopic systems indicate that the ore-forming metals and sulfur came from Mesozoic magma. The Jiawula deposit is a low-sulfidation epithermal Pb–Zn–Ag deposit, and fluid boiling is the dominant mechanism for the deposition of ore-forming materials. [ABSTRACT FROM AUTHOR]

Inner Mongolia, China, is an area with high levels of arsenic. The adverse health effects resulting from chronic arsenic exposure include skin keratosis, vascular diseases and cancers. However, the effects of arsenic exposure on mental health have not received much attention. The purpose of this study was to examine the effects of arsenic poisoning on the mental health of the inhabitants of an arsenic-affected area. We performed a cross-sectional study at two villages in Hetao Plain, Inner Mongolia. The populations of both villages were similar in age, sex, lifestyle, socioeconomic conditions, and geographic location. One hundred and thirty four (93.7%) of the 143 inhabitants in the arsenic-affected village and 36 (76.6%) of the 47 inhabitants in the arsenic-free village participated in the study. Subjects with a 30-item version of General Health Questionnaire score of 9 or more were defined as having symptoms of distress. The multiple logistic analyses showed that the mental health of the subjects in the arsenic-affected village was worse than in those in the arsenic-free village (OR=2.5, 95% CI=1.1–6.0). The effect of arsenic on mental health in arsenic-affected areas deserves further investigation. The mental health burden in arsenic-affected areas should be considered in the wider context of public and community health. [Copyright &y& Elsevier]

Background and aims: Different grazing management practices have a significant impact on the sustainability of grassland ecosystems. This study invested the vertical distribution of soil nitrogen (N) forms and soil microbial community structures in a semiarid grassland ecosystem under different grazing management practices in Inner Mongolia. Methods: Soil samples were collected from three semiarid grassland plots subjected to different long-term management practices namely, free grazing (FG) and two different periods of enclosure (E83, enclosed since 1983 and E97, enclosed since 1997). The soil organic nitrogen (N) pools were analyzed by classical methods, and the bacterial community was assessed by PCR-DGGE and high-throughput sequencing. Results: The surface soil N-supplying capacity was in the order of E97 ≥ E83 ≥ FG. The soil ammonium N, amino N, and N-supplying capacity were greater in the enclosed plots than in the FG plot. Additionally, the 0–40-cm soil layer showed the influence of different management practices on the soil properties. The structure and diversity of the soil microbial community also varied with the management type. The soil organic N composition was significantly related to the soil bacterial community structure and microbial categories. Conclusions: An appropriate number of years of fencing helps to improve the soil surface nutrient status, whereas overgrazing and prolonged enclosure are not conducive to the restoration of soil nutrients. Different grazing management practices can affect the microbial community structure and turnover of soil N in grasslands. [ABSTRACT FROM AUTHOR]

The giant Caosiyao porphyry Mo deposit, located in the northern margin of the North China Craton, is a newly discovered Mo deposit in the Yan–Liao molybdenum belt. Orebodies of the deposit are mainly hosted in metamorphic rocks of the Mesoarchean Jining Group with a small amount of orebodies in the Late Jurassic syenogranite porphyry. The ore-forming process of the deposit can be divided into three stages: an early quartz–molybdenite ± magnetite ± pyrite stage, a middle quartz–molybdenite–pyrite ± pyrrhotite ± chalcopyrite stage, and a late quartz–carbonate–pyrite ± fluorite ± pyrrhotite stage. Molybdenite Re–Os dating indicates that the Caosiyao deposit formed at ca. 150 Ma. Four types of fluid inclusions (FIs) have been distinguished in quartz phenocryst and various quartz veins including liquid-rich, gas-rich, H 2 O–CO 2 , and daughter mineral-bearing inclusions. The FIs in the quartz phenocrysts of the syenogranite porphyry contain liquid-rich, gas-rich, H 2 O–CO 2 , and daughter mineral-bearing types; their homogenization temperatures and salinities vary from 385 °C to > 550 °C and 6.5 wt% to 65.0 wt% NaCl eqv., respectively. The FIs in the quartz of the early stage are also mainly liquid-rich, gas-rich, H 2 O–CO 2 , and daughter mineral-bearing types; their homogenization temperatures and salinities vary from 243 °C to 401 °C and 6.0 wt% to 39.8 wt% NaCl eqv., respectively. The FIs in the quartz of the middle stage are mainly liquid-rich, H 2 O–CO 2 , and daughter mineral-bearing types; their homogenization temperatures and salinities vary from 208 °C to 336 °C and 1.2 wt% to 34.1 wt% NaCl eqv., respectively. The FIs in the quartz of the late stage are only liquid-rich type; their homogenization temperatures and salinities vary from 124 °C to 196 °C and 3.9 wt% to 13.2 wt% NaCl eqv., respectively. The ore-forming fluids of the Caosiyao deposit are characterized by moderate–high temperature and great fluctuating salinity, belonging to an H 2 O–NaCl–KCl–MgCl 2 –CO 2 ± CH 4 system. The δ 18 O H2O and δD H2O values of the early and middle stages vary from 3.5‰ to 7.4‰ and − 96‰ to − 77‰, respectively; the δ 18 O H2O and δD H2O values of the late stage vary from − 2.9‰ to − 0.6‰ and − 112‰ to − 77‰, respectively; indicating that the ore-forming fluids of the early and middle stages mainly consist of magmatic water and that the fluid in late stage is a mixture of magmatic and meteoric water. The δ 13 C values vary from − 16.5‰ to − 8.8‰ for the early and middle stages and − 11.4‰ to − 5.3‰ for the late stage, suggesting that the carbon of the early and middle stages consists of a mixture of organic and magmatic sources and that the carbon in the late stage was mainly from a magmatic source. The δ 34 S values range from 4.0‰ to 6.1‰ with an average of 4.8‰. The 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, and 208 Pb/ 204 Pb ratios of the metallic minerals are in the ranges of 15.962–17.832, 15.200–15.511, and 35.918–37.927, respectively. Both S and Pb isotopic systems indicate that the ore-forming metals came primarily from Mesozoic intermediate–felsic magma. The multi-stage boiling or immiscibility of the ore-forming fluids was the dominant mechanism for the deposition of ore-forming materials. [ABSTRACT FROM AUTHOR]

The giant Caosiyao porphyry Mo deposit (Yinshan area, central Inner Mongolia) is recently discovered in the northern margin of the North China Craton. The mineralization is newly molybdenite Re–Os dated to be Late Jurassic (ca. 148 Ma). LA-ICP-MS zircon U–Pb dating of the two syenogranite porphyry intrusions in the Caosiyao deposit yielded ca. 148.5 Ma and ca. 140.9–140.1 Ma, respectively, and the Caosiyao monzogranite porphyry yielded ca. 145.0 Ma. These Late Jurassic to Early Cretaceous granitic porphyries are high-K calc-alkaline and featured by high Rb, Th, U, and Zr contents and low TiO 2 , P 2 O 5 , Nb, and La contents, with high K 2 O/Na 2 O and medium to strong negative Eu anomalies, all resembling post-orogenic granitoids. The Caosiyao granitic porphyries have high whole-rock initial 87 Sr/ 86 Sr (0.710417–0.718568), low zircon ε Hf ( t ) (− 18.9 to − 12.5) and whole-rock ε Nd ( t ) (− 17.8 to − 13.7), old single-stage and two-stage model ages for zircon Hf (1282–1552 Ma and 1989–2393 Ma, respectively) and for whole-rock Nd (1766–2431 Ma and 2046–2375 Ma, respectively), as well as low K-feldspar 206 Pb/ 204 Pb (16.603–17.177), 207 Pb/ 204 Pb (15.319–15.374), and 208 Pb/ 204 Pb (36.841–37.225) values. We suggest that the Late Jurassic and Early Cretaceous syenogranite porphyry may have been sourced from a highly and moderately mature lower crust, respectively, whereas the Early Cretaceous monzogranite porphyry may have been sourced from an immature lower crust. The Caosiyao porphyries may have formed during the post-orogenic extension after the Mongol–Okhotsk Ocean closure and coeval with the Paleo-Pacific plate subduction. [ABSTRACT FROM AUTHOR]