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The ENE‐striking Chagan Obo shear zone in central Inner Mongolia is critical to constrain the termination of convergence between the North China‐Mongolia and Siberia continents. We recognized three ENE‐striking zones with strong deformation in the Permian biotite monzogranite within the shear zone and investigated the structural and kinematic characteristics. The strong deformation zones developed dense ENE‐striking and NNW‐dipping foliations. The widespread shear sense indicators such as S‐C foliations, mica fish, σ‐type, structures, and typical tight‐to‐isoclinal asymmetric folds show top‐to‐the‐SSE thrusting through NNW–SSE compression. Two 40Ar‐39Ar ages of muscovites from the muscovite quartz schists in this shear zone show 144.1 ± 1.2 Ma and 142.1 ± 0.9 Ma, respectively, providing the peak compression to be Early Cretaceous (144–142 Ma). Combined with the regional syn‐/post‐collisional magmatic rocks (166–155 Ma) related to the closure of the Mongol‐Okhotsk Ocean, this shear zone's ages (144–142 Ma) suggest that the continental convergence between the North China‐Mongolia and Siberia continents lasted from Late Jurassic to Early Cretaceous. The Early Cretaceous shoshonitic volcanism (137–133 Ma) and rift basins in this region indicate the onset of orogenic collapse in the eastern Central Asian Orogenic Belt. [ABSTRACT FROM AUTHOR]

Questions: Although the relationships between biodiversity and individual ecosystem functions under resource enrichment have been extensively studied, there is limited understanding of how resource‐induced changes affect ecosystem multifunctionality and its temporal stability, along with the underlying biological mechanisms. Location: Inner Mongolia, China. Methods: We investigated the impact of biodiversity mechanisms on ecosystem multifunctionality and its temporal stability through a 3‐year field experiment. This experiment involved augmenting growing season precipitation and nitrogen deposition, conducted in a typical steppe ecosystem of Inner Mongolia alongside regular mowing. Results: Our findings revealed that the addition of water (W) and nitrogen (N) had varying effects on ecosystem multifunctionality and its temporal stability. The combination of N and W additions enhanced ecosystem multifunctionality, whereas both W and N + W additions promoted the temporal stability of ecosystem multifunctionality. Structural equation modeling demonstrated that the community‐weighted mean height, in response to nitrogen addition, played a key role in enhancing ecosystem multifunctionality. By contrast, increased species asynchrony because of water addition and greater functional diversity in terms of leaf area contributed to heightened temporal stability of ecosystem multifunctionality. Furthermore, the positive effects of community‐weighted mean height on ecosystem multifunctionality exhibited a gradual increase with rising threshold levels. Conclusions: Our study provides the first evidence of the independent effects of selection, exemplified by community‐weighted mean and complementarity, represented by factors such as species richness, functional diversity and species asynchrony on both ecosystem multifunctionality and its temporal stability. This underscores how global change factors can directly influence ecosystem multifunctionality and its temporal stability while also indirectly modulating biodiversity effects in the short term. Overall, our findings underscore the vital role of biodiversity conservation in enhancing grassland management and the delivery of ecosystem services in the context of global change, particularly in regions subject to extensive mowing. [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]

Lophialetidae is an extinct group of endemic Asiatic tapiroids that are widely distributed in the Eocene sediments of Asia. Schlosseria magister and Lophialetes expeditus are the most abundant species in this family. However, their dietary and ecological characteristics are largely unknown. For the first time, we reconstruct the palaeodiet and habitat of these two lophialetids using a combination of mesowear and stable carbon isotope analysis of fossil teeth excavated from the Erlian Basin, China. Mesowear analysis (n = 141) suggests that the dietary structure of S. magister and L. expeditus shifted from less to more abrasive diets from ~52 to ~42 Ma. Stable carbon isotope analysis (n = 137) suggests that the habitats of S. magister and L. expeditus became drier and/or more open through time. The dietary shifts of the two lophialetids are consistent with evident changes in habitat. The changes in the diet and habitat were probably related to global climate change during that time period. The gradual drop in global temperatures during the early–middle Eocene led to a drier and more open terrestrial ecosystem in the Erlian Basin, probably resulting in changes in floral composition of the environment inhabited by S. magister and L. expeditus. Hence, herbivores highly susceptible to vegetation modification had to develop new resource exploitation strategies to adapt to these changes. Schlosseria magister, considered to be the sister‐group of L. expeditus and with a low level of ecological flexibility, was unable to adapt to the habitat changes finally becoming extinct at ~45 Ma. [ABSTRACT FROM AUTHOR]

The Hegenshan ophiolite-arc-accretionary belt adjacent to the Solonker suture in central Inner Mongolia marks the closure of a back-arc ocean basin and an Early Permian extensional setting is a critical region to understand the final closure of the Paleo-Asian Ocean in relation to the construction of the Central Asian Orogenic Belt (CAOB). Since the Paleo-Asian Ocean still existed in Solonker during Permian, the Early Permian extensional regime as indicated by the widely distributed Permian A-type granites in this accretionary belt remains enigmatic. In order to address this issue, we investigate the large-scale Early Permian EW-trending dyke swarm in the Hegenshan belt through an integrated study on petrology, zircon U-Pb isotopic ages, whole rock major-trace elements, and Sr-Nd-Pb isotopes. These dykes were emplaced in the volcanic-plutonic complex of the Carboniferous continental arc. Our zircon U-Pb results show an age range of 289.9 ± 3.6 Ma to 274.6 ± 4.6 Ma for the dyke emplacement, which is slightly younger than the post-subduction bimodal volcanic-plutonic suite (305–299 Ma) which is closely associated with the dyke swarm. Based on field characteristics and geochemical data on the dykes, we recognize two magma types: calc-alkaline dykes and A-type granitic dykes. The calc-alkaline dykes include diorite and granodiorite, whereas the A-type granitic dykes are composed of granite porphyry and rhyolite, corresponding to a major phase of Early Permian bimodal magmatism in the Hegenshan belt. The diorite-granodiorite dykes exhibit a continuous evolutionary trend of calc-alkaline magma from gabbro through diorite to granodiorite. They also display enrichment in LILEs and LREEs, and depletion of HFSEs. These characteristics are consistent with the Late Carboniferous calc-alkaline plutons which are spatially and temporally associated with the diorite-granodiorite dykes. We therefore infer a common magma system, with the parent magma sourced from enriched lithosphere mantle. The granite porphyry-rhyolite dykes show marked consistency in geochemical and Sr-Nd-Pb isotopic compositions with the Late Carboniferous A-type granite and rhyolite in this area. Compared with the calc-alkaline diorite-granodiorite dykes, the granite porphyry-rhyolite dykes have significantly higher Rb, Th, HFSEs (Nb, Ta), HREEs (Yb) and Y, and lower Sr and Ba. These rocks exhibit the features of A 2 -type granites, possibly inherited from pre-existing subduction-related juvenile lower crust. The large-scale dyke swarm with bimodal signature suggests an extensional setting in the Carboniferous continental arc. Combined with the age data (305–299 Ma) of the Late Carboniferous bimodal magmatic rocks in the study area which denote the maximum age of the slab break-off, the emplacement time of the dyke swarm (289–274 Ma) provides robust constraints on the Early Permian extensional tectonic regime (305–274 Ma) in the Hegenshan accretionary belt. The Early Permian extension in this belt occurred prior to the closure of the Paleo-Asian Ocean and formation of the Central Asian Orogenic Belt, and the Hegenshan belt likely represents a back-arc formed through the northward subduction of the Paleo-Asian Ocean during Permian. Unlabelled Image • The Permian dyke swarm marks the closure of the Hegenshan back-arc ocean. • The bimodal affinity constrains extensional regime in the Hegenshan belt. • Back-arc setting associated with northward subduction of the Paleo-Asian Ocean. [ABSTRACT FROM AUTHOR]

First Zircon U-Pb Ages of the Pigeon Hill Fossil Locality of the Jehol Biota in the Greater Khingan Mountains, Inner Mongolia. [Extracted from the article]

Although livestock grazing can strongly affect pools and cycles of phosphorus (P) in grassland ecosystems, few studies have examined how grassland management regimes influence the components of the soil P pool. Here, we use a long-term experiment in the Inner Mongolia grassland to examine how grassland management and biotic and abiotic factors affect soil P fractions. The grassland management regimes we studied included a traditional grazing system (continuous grazing, TS), a mixed grazing system (grazing and mowing rotation, MS), and a haymaking system (continuous mowing, HS). Our results showed that traditional grazing accelerated the return of P to ecosystems lost by herbivores and decoupled labile P (i.e., Ca2-P) from soil organic carbon in the topsoil (0–10 cm). Labile P was significantly reduced in the topsoil in HS (− 10%) and MS (− 24%). Mowing promoted the downward movement of soil P and the transformation of O-P to Ca2-P in the topsoil by removing large amounts of biomass and litter. Both grazing and mowing increased Fe-P and Ca10-P concentrations. The amount of labile P in the topsoil was mainly explained by plant properties, whereas the amounts of moderately labile P (Ca8-P, Al-P and Fe-P) and stable P (O-P and Ca10-P) were mainly explained by soil properties. Moreover, shifts in plant community composition resulted in substantial impacts on the soil stable P fractions. Our study demonstrates that long-term continuous grazing is detrimental to the accumulation of available nutrients in soils. Understanding how grazing and mowing affect conversion between P pools could improve adaptive grassland management in the face of global change. [ABSTRACT FROM AUTHOR]

Predicting the comprehensive driver of ecosystem multifunctionality is crucial for effective grassland management. However, the underlying biotic and abiotic mechanisms of ecosystem multifunctionality under global change and land use remain poorly understood. In this study, a 3-year field experiment was conducted in a semi-arid steppe in Inner Mongolia to investigate the relative importance of different biotic and abiotic factors in regulating aboveground ecosystem multifunctionality (AEM) and belowground ecosystem multifunctionality (BEM) in response to resource input after long-term grazing. The experiment involved three grazing intensities (1.5 low, 4.5 moderate, and 9.0 high sheep/ha) with a 7-year difference in grazing history. Precipitation (W) and nitrogen deposition (N) were manipulatively increased during the growing season. The study focused on exploring the effects of various biotic factors (e.g. species richness, functional diversity, plant functional groups) and abiotic factors (e.g. soil environment variables) on AEM and BEM. The results revealed asymmetric responses of AEM and BEM to resource input. Resource input enhanced AEM, but not BEM. However, increasing grazing intensity substantially reduced BEM, though we noted that AEM and BEM decreased the most under moderate grazing. Interestingly, the study found consistent responses of single ecosystem functions and ecosystem multifunctionality to resource input across the three grazing blocks. Structural equation modeling (SEM) analysis indicated that species richness primarily enhanced AEM, while soil environment played a major role in promoting BEM across different grazing history intensities and the whole grazed system. Multiple biotic and abiotic factors with varying relative importance in different grazing history scenarios controlled AEM and BEM. Species richness exhibited a strong influence on AEM and BEM, but within a narrow effect threshold range, whereas soil environment had a lesser effect size but a wider threshold range. This study provides the first evidence that grazing history and resource enrichment jointly regulate AEM and BEM. The findings highlight the importance of considering biodiversity conservation, soil health, and land use history in management practices aimed at maintaining ecosystem multifunctionality under climate change and human activities scenarios. • AEM and BEM decreased the most under grazing history with moderate intensity. • Resource input enhances AEM and maintains BEM after long-term grazing. • Species richness and soil factors primary controls AEM and BEM, respectively. [ABSTRACT FROM AUTHOR]

We describe a new taxon of advanced ornithuromorph bird, Khinganornis hulunbuirensis gen. et sp. nov., from the previously unreported Pigeon Hill locality of the Lower Cretaceous Longjiang Formation in the northern Greater Khingan Range area of Inner Mongolia, China. A cladistics analysis resolves K. hulunbuirensis as the sister group of a clade formed by Changzuiornis and Iteravis among ornithuromorphs. The osteohistological analysis indicates that K. hulunbuirensis is the first ornithuromorph that maintained an uninterrupted growth during a longer period characterised by slow deposition of low-vascularised and terminal avascular bone tissue. The relatively long hindlimbs and elongate pedal digits with long proximal phalanges suggest a wading and amphibious ecology for the new bird. The discovery of K. hulunbuirensis represents the first occurrence of Jehol birds in the Greater Khingan Range and documents the northernmost known geographic distribution of the celebrated avifauna in China. The new record implies more extended palaeogeographic range for the early diversification of Mesozoic birds on the eastern side of Laurasia. [ABSTRACT FROM AUTHOR]

• NPP of grassland ecosystems exhibits a memory of past precipitation events. • Wet and dry legacies exhibit asymmetric responses to precipitation transitions. • Mesic steppe shows higher response to annual precipitation change than xeric steppe. • Consecutive wetness or drought impacts the magnitude and direction of legacy effect. • Legacy effect lasts for only one year with year by year transmitting. The legacy effects of precipitation, defined as the impact of precipitation from previous years on current-year net primary productivity (NPP), have been well recognized in field experiments and site-level observational studies. However, it remains unclear how consecutive dry or wet years influence the directions and magnitude of legacies and broad-scale patterns of NPP. Here, we quantified the spatial and temporal patterns of legacy effect across different numbers of consecutive wet and dry years from 2000 to 2020 in the Inner Mongolia grassland. Spatially, the response of legacies to precipitation transitions was asymmetric along the mean annual precipitation gradient. The positive response of legacies to precipitation decrease was found for desert steppe and typical steppe after preceding wetness. In contrast, the response of legacies to precipitation increase was negative for desert steppe and meadow steppe after preceding drought. Moreover, legacies were more sensitive in desert steppe than that in typical steppe and meadow steppe for both the preceding wetness and preceding drought. However, the meadow steppe showed the highest response to the inter-annual precipitation change among the three grassland types. Furthermore, the legacies responded more strongly to precipitation decrease (preceding consecutive wet years) than the increase (preceding consecutive dry years) for meadow steppe and typical steppe. Yet, the desert steppe showed the opposite response to precipitation change. Temporally, the legacy effects lasted for only one year and could be transmitted year by year. Our findings highlight that consecutive wet and dry years play essential roles in controlling the NPP responses to climate fluctuations in arid and semi-arid grasslands. Understanding ecosystem responses to climatic periods can provide insights into the effects of directional changes in rainfall associated with climate change. [ABSTRACT FROM AUTHOR]

China has set ambitious goals to cap its carbon emissions and increase low-carbon energy sources to 20% by 2030 or earlier. However, wind and solar energy production can be highly variable: the stability of single wind/solar and hybrid wind-solar energy and the effects of wind/solar ratio and spatial aggregation on energy stability remain largely unknown in China, especially at the grid cell scale. To address these issues, we analyzed the newly 2007–2014 hourly wind and solar data, which have higher resolution and quality than those used in previous research. The stability of single wind/solar energy production clearly increased as the wind/solar energy capacity factor increased, and there were significant functional relationships between single wind/solar energy stability and the wind/solar energy capacity factor. Highly stable wind energy was concentrated in eastern Inner Mongolia, northeastern China, and northern China while highly stable solar energy was concentrated in the Tibetan Plateau, Inner Mongolia, and northwestern China. Different wind/solar ratios affected the stability of hybrid wind-solar energy through a unimodal relationship, allowing us to produce a map of optimal wind/solar ratios throughout China in order to minimize the variability of hybrid wind-solar energy production. At the optimal wind/solar ratio, the most stable hybrid wind-solar energy was concentrated in eastern Inner Mongolia, northeastern China, and northern China. The variability of single and hybrid wind/solar energy decreased as the aggregated area size increased, especially for wind-dominated energy systems. These results have important practical applications: (a) using the optimal wind/solar ratio to install simple hybrid wind-solar energy systems locally; (b) prioritizing the deployment of large-scale wind farms or centralized solar photovoltaic stations in regions with high hybrid energy stability; and (c) strongly promoting regional cooperation, such as breaking inter-provincial power grid barriers, to reduce the variability of hybrid wind-solar energy production and thus operational costs. • We analyzed new high-quality China hourly wind/solar energy data for 2007–2014. • The optimal wind/solar ratio was quantified to minimize local energy variability. • Larger aggregation areas clearly improve renewable energy stability. • We identified suitable areas for large-scale wind-solar power generation in China. [ABSTRACT FROM AUTHOR]

In grasslands, grazing can regulate the functional trait composition of plant communities through intraspecific trait variation and species turnover. However, it is not well understood how these variables affect specific plant traits. Here, we partitioned the relative roles of intraspecific trait variation and species turnover to control grazing-induced shifts in community functional composition using a field manipulation experiment with seven levels of grazing intensity in the Inner Mongolia grassland. We concurrently measured six aboveground traits (i.e. plant height, plant aboveground biomass, plant density, leaf area, specific leaf area, SLA; and leaf density) and three root traits (average root diameter, ARD; specific root length, SRL; and root tissue density, RTD) of the first-, second- and third-order roots (1st-, 2nd-, and 3rd-). Our results showed that plant above-ground traits shifted towards grazing avoidance strategies (i.e. plant height and leaf area decreased) as grazing intensity increased, and below-ground traits shifted towards conservation strategies (i.e. 1st-SRL and 2nd-SRL decreased, 1st-RTD and 2nd-ARD increased). Additionally, functional tradeoffs were found between plant individual biomass and plant density, as well as between leaf area and leaf density under grazing. However, community-weighted mean SRL (SRL CWM) and ARD (ARD CWM) exhibited functional coordination under the grazing pressures. Altogether, shifts in community functional trait composition were predominantly governed by intraspecific variation in above- and below-ground traits, while changes in mean trait values among plant species with different resource strategies were mainly triggered by species turnover. Our results demonstrated that both above- and below-ground trait compositions in plant communities shifted towards conservation strategies under high levels of grazing intensity. Ultimately, this study highlights the important role of intraspecific trait variation in governing grazing-induced changes in the community above- and below-ground functional trait composition, which advances fundamental knowledge on the mechanisms of plant community assembly in semiarid grasslands. • Grazing regulates plant functional traits and community trait composition in grasslands. • Grazing shifted trait composition of plant communities towards conservation strategies. • Intraspecific trait variation governs variations in community trait composition. • Plant community above- and below-ground trait composition are synergistic under grazing. [ABSTRACT FROM AUTHOR]

Soil diazotrophs convert atmospheric nitrogen (N) into biologically active N, which is an important N source for plants and microbes in many natural ecosystems. However, responses of diazotrophic communities to long-term N and phosphorus (P) inputs and the primary mediators remain unclear, particularly in semi-arid grasslands. Here we show that the abundance and community composition of diazotrophs responded distinctly to gradients of long-term N and P additions in an Inner Mongolia steppe. Our results showed that moderate to high N inputs (105–280 kg N ha−1 yr−1) significantly reduced both diazotrophic abundance and community diversity. In contrast, low to moderate P additions (20–80 kg P 2 O 5 ha−1 yr−1), along with low N input (24 kg N ha−1 yr−1), significantly increased diazotrophic abundance, while having no significant effects on soil diazotrophic diversity and community structure. Also, long-term N and P inputs led to different co-occurrence patterns in the diazotrophic community, although both of them reduced the stability of diazotrophic co-occurrence network. Structural equation modeling (SEM) analysis further revealed that N additions suppressed the diazotrophic abundance and diversity, corresponding to the decreasing stoichiometric ratio of soil available C to N. Together, these results indicate that nutrient-induced changes in the relative availability of C to N in soil primarily drives the impacts of nutrient enrichment on diazotrophs. These findings suggest that management regimes with low nutrient inputs may provide unique opportunities to increase plant productivity, while sustaining or even enhancing the abundance and activity of soil diazotrophs. • Nutrient addition effects on soil diazotrophs were examined in a Mongolian steppe. • Moderate to high N input significantly reduced diazotrophic abundance and diversity. • Low N and P additions enhanced the abundance of diazotrophs and their associations. • High N and P additions reduced the stability of diazotrophic co-occurrence network. • The C:N stoichiometry primarily drove the response of soil diazotrophs to N input. [ABSTRACT FROM AUTHOR]

Reptiles are especially vulnerable to climate warming because their behavior, physiology, and life history are highly dependent on environmental temperature. In this study, we envisaged new probable mechanisms underlying the high vulnerability of lizards, wherein heat exposure induces oxidative stress and leads to immunosuppression. To test this hypothesis, we conducted a warming experiment on a lizard (Eremias multiocellata) from a desert steppe in Inner Mongolia from May to September using open-top chambers set up in their natural habitat and compared the components of oxidative stress (antioxidant ability [Superoxide dismutase (SOD) activity], extent of oxidative damage [malondialdehyde (MDA) content]), and immunocompetence (white blood cells [WBC] counts and immunoglobulin M [IgM] expression) between the warming and control groups. At the end of the experiment, the warming treatment did not affect the survival rate of the lizards. However, MDA content, but not SOD activity, was significantly higher in the warming group than in the control group. The WBC counts and IgM expression were significantly lower in the warming group than in the control group. Our results verified our hypothesis and provided novel cues and methods for the investigation of the mechanisms behind the high probability of extinction of other ectotherms under warming conditions. • Heat exposure induced oxidative stress. • Heat exposure led to immusuppression. • Providing new mechanisms that may contribute to the risk of extinction of lizard populations. [ABSTRACT FROM AUTHOR]