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In order to study the influence of reclamation of open-pit coal mine dump on soil physical properties, the dump platform of Heidaigou open-pit mine in Zhungeer Banner, Ordos City, Inner Mongolia Autonomous Region, was as the research object. The difference of physical properties in 0-60 cm soil layer among natural landform (ZR), unreclaimed dump (WF) and 5-year reclaimed dump (FK) in mining area were analyzed, the effects of reclamation on soil physical properties of dump were studied by variance analysis and principal component analysis. The results showed that the soil bulk density and gravel content of unreclaimed dumps were significantly higher than those of reclaimed dumps and natural landforms, while the soil moisture content, saturated moisture content and field water holding capacity were lower than those of reclaimed dumps and natural landforms, among which the field water holding capacity was significantly different from those of reclaimed dumps and natural landforms. The correlation analysis and regression equation fitting analysis showed that the gravel content in soil affected soil bulk density and water holding capacity. Reclamation made the soil bulk density and gravel content decrease, and the soil moisture content, saturated water content and field water holding capacity increase. With the increase of soil depth, the soil unit weight, moisture content and saturated moisture content of the dump showed an increasing trend, while the field water holding capacity and gravel content showed a decreasing trend. The comprehensive scores of the 40-60 cm soil of 5-year reclaimed dump, 40-60 cm soil of natural landformand 20-40 cm soil of 5-year reclaimed dump were ranked as 1st, 2nd and 3rd, respectively, which indicated that the reclamation of the dump could improve the soil and optimize the soil texture. The depth of soil improvement by plants could reach 60 cm soil layer in the case of 5 years of reclamation of the dump. Above results provided certain guiding for reclamation work in mining area. [ABSTRACT FROM AUTHOR]

The mineral system modeling approach for prospectivity mapping is an efficient and economic method to assess undiscovered mineral potential quantitatively. It is a procedure of modeling, acquiring, and coupling the proxies of footprints of mineral systems at multiple scales (e.g., regional, district, and deposit scales). In this approach, the critical issue from multiple scales is that the data collected are asymmetrical from the superficial to the deep or from mine to its brown fields, so that it is hard to employ and integrate them. To complete this study, firstly, multi-tactic 3D geological modeling methods, including the explicit, the implicit, and inversion, were used to build geological models in the condition of asymmetrical datasets at the deposit and district scales. Secondly, indicators acquired in drill-intensive fields among multisource datasets composed of geology, geochemistry, geophysics and alteration data were transferred to studies in deep and brown fields. Finally, deep (~ 1,100 m) and circumjacent potentials of mine were targeted in the Haoyaoerhudong gold deposit situated in the Urad Middle Banner area, Inner Mongolia, which is one of the largest black-rock-series-type gold mines in China. This proposed procedure is more visual, clear, intuitive, and transferable to drive mineral system approach to exploration discovery than previous GIS-based studies. [ABSTRACT FROM AUTHOR]

Brachyericinae is a subfamily of Erinaceidae (hedgehogs and moonrats) with a very short history and limited distribution. Fossil records of brachyericines, with rare materials, were confined to the Oligocene and early Miocene in Central Asia and to the Miocene in North America. Here, we report three forms of short-faced hedgehogs: Synexallerix junggarensis, Brachyericinae gen. et sp. indet. 1 and Brachyericinae gen. et sp. indet. 2 from Aoerban and Gashunyin Adege, localities of the early Miocene in Central Nei Mongol. S. junggarensis is the first discovery outside the Suosuoquan Formation in Xinjiang and detailed description of the new materials, including a nearly complete skull, clarifies its taxonomic position within the Brachyericinae. The new Nei Mongol material is important not only because they include a nearly complete skull of S. junggarensis (previously known by a rostral part of the skull) but also because of the presence of three taxa of the brachyericines from the same general area. The similarity of its morphological characteristics with the North American genera also further confirms the close affinities of brachyericines from the two continents during the early Miocene. [ABSTRACT FROM AUTHOR]

Desertification and the expansion of deserts are regarded as a major threat to human livelihoods and ecosystem services, as well as achieving Sustainable Development Goals. Humans have been recognized as significant agents in the expansion of desert‐like conditions, through the agency of desertification/land degradation, and through contributions to global climate change. Yet, how desertification changes and whether human or climate change drives these processes and trends over the whole Mongolia Plateau is still not clear. Here we first use MODIS data for 2000–2019 to assess the long‐term vegetation changes across the Mongolian Plateau, both in Inner Mongolia of PR China and the Mongolian People's Republic. We then appied a General Linear Model to analyze the additional climate and human attribute data sets to explore relationships between the observed desert extent reduction and their potential drivers. Results show that from 2000–2019, desert extent declined by over 7%, comprised of an almost 11% reduction in Inner Mongolia and 5% reduction in Mongolia, and a reduction in the degree of desert conditions, as measured by vegetation cover grades, across the whole region (37.5% decline ‐ one grade in PR China, 28.75% in Mongolia). The majority of desert area reduction occurs in the northern and eastern areas of the Mongolia Plateau. We found that the main drivers of changing desert extent is not because of a reduction in human pressures on the land, but an increasing trend of both precipitation and temperature, which explains over 75% of all the observed changes. Besides, urbanization, and a reduction of population pressures on the land, contribute to most of the remaining changes. Our results suggest that although the climate has been the primary driver of changing desert area and severity, human interventions have played an important role, although the way it intervenes and the intensity varies in Inner Mongolia and Mongolia. Human's active response to land degradation in the desert contributes to more land restoration in Inner Mongolia than in Mongolia. [ABSTRACT FROM AUTHOR]

Utilization of fly ash is of great importance in China in the context of resource and environmental crises. Different fly ash utilization processes are proposed, and some have been practically applied. However, none of these fly ash utilization pathways has been evaluated comprehensively by integrating both environmental and economic perspectives. In this study, three high-aluminum fly ash utilization methods in Mongolia were assessed and compared based on the concept of eco-efficiency. The environmental assessment was conducted in accordance with life-cycle assessment principles, and a monetization-weighting approach was applied to obtain social willingness-to-pay as a reflection of environmental impact. The environmental assessment results revealed that the reuse of fly ash had significant advantage for saving primary resource, while solid waste, depletion of water, and global warming were the three highest environmental impacts from the life cycle perspective. The economic performance assessment showed positive net profits for fly ash utilization, but high value-added products were not necessarily indicative of better economic performance due to the relatively high operation cost. Comparison of the eco-efficiency indicators (EEIs) implied that the process of scenario 1#, which produced mullite ceramic and active calcium silicate, was the most recommended out of the three scenarios on the present scale. This judgment was consistent with the evaluation of the resource utilization rate. The present study showed that the EEI could be used to compare different fly ash utilization processes in a comprehensive and objective manner, thus providing definitive and insightful suggestions for decision-making and technical improvement. [ABSTRACT FROM AUTHOR]

• F18 and F39 altered distributions of medium mineral elements in plant and soil. • F18 and F39 shifted medium mineral elements from root to other parts. • Ca, Mg, and Si were shifted from soil to plant at F39 than F18. • Ca was shifted from root to litter at F39 than F18. • Mg, S, and Si were shifted from litter to root or green plant at F39 than F18. The variations of medium mineral elements in long-term grazing exclusion grassland have been few studied. Therefore, the contents, stocks, and proportions of calcium (Ca), magnesium (Mg), sulphur (S), and silicon (Si) in green plant-litter-root-soil continuum were evaluated by grazing exclusion for 18-, and 39-year (F18 and F39) and continue grazing (F0) in Mongolia grassland. Results showed that F18 and F39 decreased the stocks of Mg and Si in green plant and the stocks of Ca and Mg in 20–50 cm root (p < 0.05). F18 and F39 increased the stocks of S in 0–100 cm soil and the stocks of elements in litter (p < 0.05). Compared to F18, F39 increased the stocks of elements in 0–20 cm root, especially Si (p < 0.05), and a 30.3 % higher of Ca stock in green plant was observed (p < 0.05). The stock of Ca and Mg in 0–100 cm soil at F39 was 164.3 % and 72.6 % lower than that at F18, respectively (p < 0.05). F39 decreased the stocks of Mg, S, and Si in incomplete- and complete decomposed litter relative to F18. We concluded that four elements were shifted from root to other parts with long-term grazing exclusion. However, Ca, Mg, and Si were shifted from soil to plant with grazing exclusion for 39 years relative to 18 years, and Ca was shifted from root to litter, and Mg, S, and Si were shifted from litter to root or green plant. [ABSTRACT FROM AUTHOR]

Based on the dipodid materials collected from Siziwang Qi, Nei Mongol in 2009, a new speciesBrachyscirtetes tomidaisp. nov.is erected. It is characterised by its smaller size, more bunodont paracone on M2, more separate mesoloph and posteroloph on M2 and separate mesolophid on m2, more longitudinally symmetrical protoconid–metaconid complex diverging at an obtuse angle and elongated anterior part of ectolophid on m1 than existing species. It represents the most primitive known species of this genus. Judging from the associated mammals, the age ofBrachyscirtetes tomidaishould be late Late Miocene.Brachyscirtetesis possibly derived from a form of early Late MioceneParalactaga. Its dental trends include increasing size and crown height, and increasing lophodonty of occlusal morphology, which is reflected as gradual fusion of mesoloph and posteroloph with paracone, metacone on M2 and of mesolophid with entoconid on m2, respectively; the protoconid–metaconid complex on m1 shifts from a longitudinally symmetrical position to an anterolabial orientation, and the anterior part of ectolophid on m1 is gradually shortened, shifting from a longitudinal to an oblique orientation. The appearance ofBrachyscirtetesand abundant herbivores indicates an arid and steppe environment in late Late Miocene Siziwang Qi area. [ABSTRACT FROM PUBLISHER]

Enclosing plays a crucial role in vegetation and soil quality in grassland. The biomass of green plants, litter, and vertical distributions of soil physical properties and nutrient stocks were evaluated at plot enclosed long term for 38 years inside a fence and a long-term grazing plot outside a fence in a semi-arid grassland of Inner Mongolia. The results showed that dry matter of green plants and litter during the 38-year enclosing treatment was higher than in the grazing treatment (p < 0.01). The soil silt (2–50 μm) in the 38-year enclosing treatment was 5.9% higher than in the grazing treatment (p < 0.01) in 0–10 cm soil, and the fine sand (100–250 μm) was 6.0% lower (p < 0.05). The 38-year enclosing treatment slightly decreased the bulk density and significantly decreased the electrical conductivity in each soil layer (0–100 cm). The 38-year enclosing treatment significantly increased the stocks of soil organic carbon (SOC), available phosphorus (AP), and available potassium (AK) on the surface soil, and obviously decreased the stocks of total nitrogen (TN), total phosphorus (TP), calcium (Ca), magnesium (Mg), sulfur (S), and available nitrogen (AN) in each soil layer (0–100 cm). In conclusion, long-term enclosing improved grassland production, but decreased most nutrient stocks in soil. [ABSTRACT FROM AUTHOR]

Grazing exclusion has been widely implemented in degraded grassland. However, the changes of plant communities and soil nutrients in response to fencing are still controversial. Thus, the effects of free grazing, 17 and 36 years of fencing on the plant biomass and litter biomass, carbon (C), nitrogen (N) and phosphorus (P) concentrations and stocks of plant, litter and soil were investigated in the temperate steppe grasslands of northern China. The results indicated that fencing increased the aboveground live biomass and litter biomass. In addition, fencing increased C, N and P stocks of aboveground live biomass, litter biomass and soil. Although root biomass and its nutrient stocks were also significantly increased by 17 years of fencing, they were decreased with fencing extending from 17 to 36 years. Moreover, there were no significant differences in aboveground live biomass and soil N and P stocks between 17 and 36 years of fencing. Litter biomass and its C, N and P stocks were positively correlated with soil C, N and P stocks. Our results demonstrated that 17 years of fencing is an effective way to restore vegetation and soil nutrients in the temperate steppe of Inner Mongolia, but a longer fencing duration has no further positive effects on biomass production and soil nutrients accumulation. [ABSTRACT FROM AUTHOR]

In arid and semi-arid regions, a better understanding of the effect of climate change mechanisms on environmental evolution can be used to guide regional ecological conservation and to improve water resource availability. Increased aridity in arid and semi-arid regions considerably affects the physiological functions of plants and the exchange of carbon and water with the environment. We collected Pinus tabuliformis Carr. samples from Ordos, Inner Mongolia, and measured their δ18O variations. Vapour pressure (VP) was the main factor dominating δ18O variations from July to August, indicating the regulatory role of plant leaf stomata. Based on the δ18O series in the Ordos region, we reconstructed VP variations for July–August (VPJA) for the past 205 years. Spatial analysis showed the reconstruction as spatially highly representative. VP variations in the Ordos region mainly reflected precipitation variations and did not show a significant correlation with temperature. Since the late 1950s, VP has been decreasing, which is related to the weakening of the Asian monsoon. The results of reconstruction decomposed using ensemble empirical mode decomposition showed that El Niño–Southern Oscillation may affect VP in the study area, and the effect of sea surface temperature on the central and eastern Pacific Ocean in the Ordos region may lead to an increase in the drought. [ABSTRACT FROM AUTHOR]

Grazing and enclosing are two of the most important grassland managements. In order to evaluate the effects of different managements on the ecosystem balance of grassland, the vertical distributions of soil nutrients and their stoichiometric ratios were determined in the plots of grazing and enclosing over 38 years in a semi-arid grassland of Inner Mongolia. The results showed that total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), calcium (Ca), magnesium (Mg) and sulfur (S) contents in 0–100 cm soil in the long term enclosing plot were lower than the long term grazing plot and these changes were much greater in the surface soil than in deep soil. However, the soil organic carbon (SOC) and available phosphorus (AP) contents in the long term enclosing plot in the surface soil were higher (p < 0.01) compared with the long term grazing plot. In addition, long term enclosing increased the C/N ratio in each soil layer and improved C/K and C/P ratios in the surface soil compared with long term grazing. However, significant decreases of N/P and N/K ratios in the long term enclosing plot in each soil layer were observed. In conclusion, enclosing for 38 years decreased most of nutrients and reduced the nutrients' mineralization in the surface soil especially and thus might restrict nutrients cycling in a semi-arid grassland of Inner Mongolia. [ABSTRACT FROM AUTHOR]

Understanding the modes of occurrence of elements in coal is important, not only to help properly evaluate the impacts of potentially toxic elements on the environment and human health but also to provide technical guidance for recovering critical elements from coal ash. Statistical and multivariate data analysis methods have widely been used, together with physical and chemical methods, to determine the modes of occurrence of elements in coal. However, some of the statistical methods, e.g., average linkage hierarchical clustering algorithm have some disadvantages (e.g., statistical errors and poor visualization). A self-organizing map is an unsupervised artificial neural network, and it is known for its high data mining capability and excellent data visualization. In contrast to the average linkage hierarchical clustering algorithm that is commonly used for analyzing the modes of occurrence of elements in coal, the self-organizing map algorithm can provide a topological relationship among elements instead of merely providing the groups to which the elements belong. This paper focuses on the application of self-organizing map to coal elemental data for analyzing the modes of occurrence of elements in coal. Samples used in this study are from the Adaohai, Hailiushu, and Datanhao mines, all located in the Daqingshan Coalfield, Inner Mongolia, China. The results obtained from the self-organizing map algorithm are compared with those produced by average linkage hierarchical clustering algorithm. Based on the previous investigations (mainly direct methods) and further analysis, it can be concluded that the results from the self-organizing map algorithm in this investigation are more consistent with the geochemical nature and previous investigations by direct methods than those from average linkage hierarchical clustering algorithm. Consequently, the self-organizing map algorithm is a new reliable and intuitive method for analyzing the modes of occurrence of elements in coal. [ABSTRACT FROM AUTHOR]

Abstract: The emergence of C4 photosynthesis in plants as a significant component of terrestrial ecosystems is thought to be an adaptive response to changes in atmospheric CO2 concentration and/or climate during Neogene times and has had a profound effect on the global terrestrial biosphere. Although expansion of C4 grasses in the latest Miocene and Pliocene has been widely documented around the world, the spatial and temporal variations in the C4 expansion are still not well understood and its driving mechanisms remain a contentious issue. Here we present the results of carbon and oxygen isotope analyses of fossil and modern mammalian tooth enamel samples from the central Inner Mongolia. Our samples represent a diverse group of herbivorous mammals including deer, elephants, rhinos, horses and giraffes, ranging in age from the late Oligocene to modern. The δ 13C values of 91 tooth enamel samples of early late-Miocene age or older, with the exception of two 13 Ma rhino samples (−7.8 and −7.6‰) and one 8.5 Ma suspected rhino sample (−7.6‰), were all less than −8.0‰ (VPDB), indicating that there were no C4 grasses present in their diets and thus probably few or no C4 grasses in the ecosystems of the central Inner Mongolia prior to ~8 Ma. However, 12 out of 26 tooth enamel samples of younger ages (~7.5 Ma to ~3.9 Ma) have δ 13C values higher than −8.0‰ (up to −2.4‰), indicating that herbivores in the area had variable diets ranging from pure C3 to mixed C3–C4 vegetation during that time interval. The presence of C4 grasses in herbivores'' diets (up to ~76% C4) suggests that C4 grasses were a significant component of the local ecosystems in the latest Miocene and early Pliocene, consistent with the hypothesis of a global factor as the driving mechanism of the late Miocene C4 expansion. Today, C3 grasses dominate grasslands in the central Inner Mongolia area. The retreat of C4 grasses from this area after the early Pliocene may have been driven by regional climate change associated with tectonic processes in central Asia as well as global climate change. [Copyright &y& Elsevier]

The Late Jurassic tectonic environment of western part of northern margin of the North China Craton (NNCC) remains poorly understood due to weak magmatism in the Jurassic period and complications by supposedly superimposed effects of activities related with the Mongol-Okhotsk and the Paleo-Pacific tectonic regimes. In this study, we for the first time discovered and reported an A-type granite (Yingongshan granite) in the western NNCC in the Late Jurassic period. The Yingongshan granite is dated at 150 Ma years old. The Yingongshan granite is characterized by high contents of total alkalis (Na 2 O + K 2 O = 8.23–9.51%) and high field strength elements (Zr + Nb + Ce + Y = 289–705 ppm) and Ga/Al ratios (10,000 × Ga/Al = 3.01–4.05). Based on these geochemical characteristics and differentiation trend, it can be reasonably inferred that initial composition of the Yingongshan granitic melt exhibited an A-type magmatic affinity. In addition, results of zircon saturation thermometer show high magmatic temperature (> 887 °C) for the initial magma, which is consistent with its A-type granite affinity. Furthermore, the Yingongshan granite showed negative ε Nd (t) values (−14.5 to −13.3) and zircon ε Hf (t) values (−13.6 to −17.4) and contain mafic magmatic enclaves. Compared with the host Yingongshan granite rocks, the enclaves showed even lower ε Nd (t) values (−14.9 to −14.6) and zircon ε Hf (t) values (−16.9 to −19.5). Such "reversed isotope" characters indicate injection of a magma derived from the enriched lithospheric mantle during formation of the Yingongshan A-type granite. Therefore, we suggest that the latest Jurassic Yingongshan A-type granite was derived from partial melting of preexisting calc-alkaline granitoids in the crust at low pressure and high temperature under influence of magma intrusion derived from the enriched lithospheric mantle. Discovery of the Yingongshan A-type granite in this study indicates that local extension occurred as early as 150 Ma in the western NNCC, although previous studies suggest that extensive extension occurred since 132 Ma. In addition, based on the data obtained in this study combined with statistics of published zircon U–Pb age data and distribution localities of magmatic rocks in the NNCC from the literatures, we suggest that the latest Jurassic local extension in the western NNCC revealed in this study may have resulted from the collapse of the Mongol-Okhotsk orogen. [Display omitted] • Recognition of latest Jurassic A-type granite for the first time in the western NNCC. • Tectonic extension occurred in the western NNCC as early as 150 Ma. • The latest Jurassic extension was likely related to Mongol-Okhotsk orogenic collapse. [ABSTRACT FROM AUTHOR]