Mongolia Region Research Articles

Sunflower Origin Identification Based on Multi-Source Information Fusion Technique of Kernel Extreme Learning Machine

This study constructs a model for the rapid identification of the origins of edible sunflower (Helianthus) using Kernel Extreme Learning Machine (KELM) with multi-source information fusion technology. Near-infrared spectroscopy (NIRS) and nuclear magnetic resonance spectroscopy (NMRS) were utilized to analyze 180 sunflower samples from the Xinjiang, Heilongjiang, and Inner Mongolia regions. Initially, the identification models for the origin of sunflowers using NIR and NMR data were compared between two algorithms: the Extreme Learning Machine (ELM) and KELM, combined with various spectral preprocessing methods. The experiment found that the NIR spectral model preprocessed with standard normal variate (SNV) using the KELM algorithm was the most accurate, achieving accuracies of 98.7% in the training set and 97.2% in the test set. The spin-echo NMR spectral model preprocessed with non-local means (NLMs) using the KELM algorithm was the second best, with accuracies of 98.4% in the training set and 96.4% in the test set. To further improve the accuracy of the identification models, innovative sunflower origin identification models were developed based on data layer fusion and feature layer fusion using NIRS and NMRS. In the data layer fusion model, the KELM algorithm model was optimal, achieving a test set accuracy and F1 score of 98.2% and 98.18%, respectively, an improvement of 1.0% over the best single data source model. In the feature layer fusion model, four types of feature-layer information-fusion identification models were established using two feature extraction algorithms, Competitive Adaptive Reweighted Sampling (CARS) and Variable Importance Projection (VIP), combined with joint feature and simple merging feature strategies. The CARS-KELM algorithm combined with the joint feature method was found to be the best, achieving 100% accuracy in both the training and test sets, an improvement of 2.8% over the best single data source model. Identifying the origin of edible sunflower using NIRS and NMRS is demonstrated as feasible by the results. The best single-spectrum sunflower origin identification model was achieved using the KELM algorithm with SNV preprocessing. The feature layer fusion method combining NIRS and NMRS data is suitable for handling the task of sunflower origin identification. This method significantly improves the recognition accuracy of the model compared to a single model, achieving fast and accurate origin identification of edible sunflowers. The research results provide a new method for rapid identification of sunflower origin.

Time-Series Analysis of Mining-Induced Subsidence in the Arid Region of Mongolia Based on SBAS-InSAR

Mongolia’s substantial mineral resources have played a pivotal role in its economic progress, with mining activities significantly contributing to this development. However, these continuous mining operations, particularly at the Oyu Tolgoi copper and gold mine, have induced land subsidence that threatens both production activities and poses risks of geological and other natural disasters. This study employs the Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique to monitor and analyze time-series surface subsidence using 120 Sentinel-1A datasets from 2018 to 2022. The findings reveal that the SBAS-InSAR method successfully captures the subsidence and its spatial distribution at Oyu Tolgoi, with the maximum cumulative subsidence reaching −742.01 mm and the highest annual average subsidence rate at −158.11 mm/year. Key drivers identified for the subsidence include variations in groundwater levels, active mining operations, and changes in surface stress. This research underscores the ongoing subsidence issue at the Oyu Tolgoi mining area, providing crucial insights that could aid in enhancing mining safety and environmental conservation in the region.

Stability Analysis of Open-Pit Bench Slope under Repeated Heavy Vehicle Loading Based on Stress-Corrosion Model

In the present study, we address an important and increasingly relevant topic in mining safety and efficiency, namely the stability of open-pit bench slopes subjected to daily heavy truck cyclic loading. Specifically, we focus on the stability of Zhahanur open-pit slope (Inner Mongolia region, China) and investigate the potential role of daily heavy truck cyclic loading in bench slope instability. To this end, we incorporate a stress corrosion model into the particle flow code to develop a time-dependent deformation model of the rock. With the established model, we quantitatively analyse the effect of heavy truck cyclic loading on the bench slope stability. Our results support the hypothesis that daily heavy truck loading can cause gradual downward deformation of a rock mass, leading to slope instability. To validate our numerical modelling results, we compare and analyse them with in situ monitoring data. Our study demonstrates the significant impact of daily heavy vehicles on bench slope stability in open-pit mines and provides a practical tool for assessing the long-term stability of open-pit bench slopes and optimising mining operations.

Analysis of pollen sensitization characteristics of artemisia allergic rhinitis in three urban and rural areas of Inner Mongolia

Objective: To investigate the distribution rules of artemisia pollen and the clinical sensitization characteristics of allergic rhinitis (AR) induced by artemisia pollen in three urban and rural areas of Inner Mongolia. Methods: From March to October 2019, in 3 central cities (Chifeng, Hohhot, Ordos) and rural areas of Inner Mongolia, an epidemiological investigation method combining multi-stage stratified random sampling and face-to-face questionnaire survey was adopted to screen suspected AR patients, and skin prick test (SPT) was applied for diagnosis. At the same time, pollen monitoring was carried out in 3 areas to analyze the distribution and clinical sensitization characteristics of artemisia pollen.SPSS26.0 statistical software was used to process all the data. Chi-square test was used to compare rates among different age, sex, region and nationality, Spearman test was used to describe correlation analysis, and pairwise comparison of positive rates among multiple samples was used Bonferroni method. Results: Among the 6 393 subjects, 1 093 cases were diagnosed with AR, and the prevalence of AR was 17.10% (1 093/6 393). Among them, pollen-induced allergic rhinitis, the prevalence of PiAR was 10.97% (701/6 393), accounting for 64.14%(701/1 093).The highest incidence was in the youth group (20-39 years old), accounting for 46.94% (329/701).The diagnosed prevalence was higher in females than in males (11.35% vs. 10.64%, χ2 value 12.304, P<0.001).The prevalence rate of ethnic minority was higher than that of Han nationality (13.01% vs. 10.65%, χ2 value 6.296, P=0.008).The prevalence in urban areas was also significantly higher than that in rural areas (18.40% vs. 5.50%, χ2 value 10.497, P<0.001).There was significant difference in prevalence rate among the three regions in Inner Mongolia (6.06% in Chifeng, 13.46% in Hohhot, 16.39% in Ordos, χ2 value 70.054, P<0.001).The main clinical symptoms of artemisia PiAR were sneezing (95.58%), nasal congestion (91.73%) and nasal itching (89.30%).Allergic conjunctivitis accounted for 79.60% (558/701), chronic sinusitis for 55.63% (390/701), asthma for 23.25% (163/701).The pattern of artemisia pollen sensitization was mainly multiple sensitization, and the frequency of clinical symptoms and clinical diseases induced by hypersensitization with other allergens accounted for more than that caused by single artemisia pollen. The spread period of Artemisia pollen in the three regions was from June to October, and the peak state was in August in summer. The peak time of clinical symptoms in artemisia PiAR patients was about 2 weeks earlier than the peak time of pollen concentration, and the two were significantly positively correlated (R=0.7671, P<0.001). Conclusion: Artemisia pollens are the dominant pollens in late summer and early autumn in Inner Mongolia, and the prevalence of artemisia PiAR is high. Controlling the spread of Artemisia pollens is of great significance for the prevention and treatment of AR.

Devonian to Mississippian strata of the Shine Jinst region revisited: Facies development and stratigraphy in southern Mongolia (Gobi Altai Terrane)

AbstractThis report provides new stratigraphical and facies data from Devonian and Carboniferous rocks in the Shine Jinst region (Trans Altai Zone, southern Mongolia) with a special focus on the Lower Devonian Chuluun Formation, the Middle Devonian Tsagaankhalga Formation, and the Upper Devonian to Mississippian Heermorit Member of the Indert Formation. Facies development in the Shine Jinst region exhibits a fundamental break in the carbonate platform evolution in the Lower Devonian as reef building organisms were affected by a major regression and deposition of several metres-thick conglomerates at the base of the Tsakhir Formation (Lower Devonian). The overlying Hurenboom Member of the Chuluun Formation is composed of fossiliferous limestones. Reef building organisms, such as colonial corals and stromatoporoids show low diversity and exhibit limited vertical growth and lateral extension of individuals. Thus, they do not represent a real reef as proposed in previous publications but biostromal limestones instead. One reason might be the isolated position of the Shine Jinst region between an unknown continent and a volcanic arc in the early Middle Devonian that hampered the successful colonization in shallow-water areas. Bivalves of the Alatoconchid family were once grouped into reef builders or biostrome builders and they are known only from Permian rocks. The found bivalve biostomes in Mongolia may represent precursors, which would document the oldest record of Alatoconchids found in the world. Remarkable thicknesses of massive crinoidal grainstones (“encrinites”) are documented in many parts of the succession, which suggest rather stable environmental conditions of a carbonate ramp setting at different times. The occurrence of thick-bedded conglomerates in the Shine Jinst section is not restricted to the Lochkovian to Pragian interval (Tsakhir Formation), but also occurs in the Eifelian. A thick-bedded conglomerate, which is interpreted to represent braided fluvial or fan-delta to shallow-marine deposits occurs at the base of the Tsagaankhaalga Formation. A steep relief associated with uplift and volcanism seems to be a realistic scenario for deposition of these sediments. This succession points to a remarkable tectonic uplift or sea-level fall in the Middle Devonian. Conodont findings of the studied section confirm the occurrence of time-equivalent strata of the Choteč Event, the Dasberg Crisis, and the Hangenberg Event found elsewhere in the world, which are described from Mongolia for the first time. Sedimentological descriptions, revised biostratigraphical data, and U-Pb dating by LA ICP-MS of some volcaniclastic rocks from the Chuluun Formation are presented in this report. The studied section records a complex interaction of sedimentation, regional tectonics, sea-level changes and coeval volcanism, which is very similar to other regions in Mongolia. The new data provide the background for further scientific studies in this region. This is a contribution to the Special Series on “The Central Asian Orogenic Belt (CAOB) during Late Devonian: New insights from southern Mongolia”, published in this journal.

A Circular-Linear Probabilistic Model Based on Nonparametric Copula with Applications to Directional Wind Energy Assessment.

The joint probability density function of wind speed and wind direction serves as the mathematical basis for directional wind energy assessment. In this study, a nonparametric joint probability estimation system for wind velocity and direction based on copulas is proposed and empirically investigated in Inner Mongolia, China. Optimal bandwidth algorithms and transformation techniques are used to determine the nonparametric copula method. Various parameter copula models and models without considering dependency relationships are introduced and compared with this approach. The results indicate a significant advantage of employing the nonparametric copula model for fitting joint probability distributions of both wind speed and wind direction, as well as conducting correlation analyses. By utilizing the proposed KDE-COP-CV model, it becomes possible to accurately and reliably analyze how wind power density fluctuates in relation to wind direction. This study reveals the researched region possesses abundant wind resources, with the highest wind power density being highly dependent on wind direction at maximum speeds. Wind resources in selected regions of Inner Mongolia are predominantly concentrated in the northwest and west directions. These findings can contribute to improving the accuracy of micro-siting for wind farms, as well as optimizing the design and capacity of wind turbine generators.

清康雍乾时期内蒙古中西部地区山林开发与林权问题探析

During the Qing dynasty, the wood tax was a non-negligible part of the source of customs duties of the imperial court, therefore, the nationwide mountain and forest exploitation activities carried out by both the official supervision as well as the local and social businessmen and citizens were very active. In the wave of resource exploitation and utilization, the Mongolian Banner Mountain products, which were still under the domain of Mongolia, had also been stolen and sold, becoming a “special area” under the situation of banning. There are countless discussions of different dimensions on the mining process as well as the banning and unbanning time of Daqing Mountain and Muna Mountain forests in the central and western regions of Inner Mongolia. However, it is still necessary to discuss in depth about how the imperial court handled the mining, transportation and sale of the mountain forests in this area under the “blocked” state. In other words, why did the Qing court strictly impose a policy of banning the border areas while allowing the smuggling and selling of mountains and forests to occur, and even the official supervision and commercial office of felling and transporting wood plants in the Muna Mountains. In addition, during the process of mining and selling mountain wood vegetation, the ownership right of its mountain forest has gradually formed in the unique form of “boundary” or “the forbidden”, which has become a unique form of mountain forest ownership in Mongolia. Among them, the process of temples in Mongolia region confirming the rights to the surrounding mountains and forests is clearer than that of the local society or the country, which fully demonstrates its unique nature.

Effect of Biochar Application on the Improvement of Soil Properties and Buckwheat (Fagopyrum esculentum Moench) Yield on Two Contrasting Soil Types in a Semi-Arid Region of Inner Mongolia

Biochar application to soil is widely recognized as a promising agricultural management practice to increase crop production by enhancing the physical, chemical, and microbiological properties of the soil. Despite the fact that numerous studies have investigated biochar production and alterations in soil properties, the effects of biochar on contrasting soils within the same region remain poorly understood, especially for semi-arid regions. Therefore, a three-year field experiment was initiated in 2020 wherein biochar was applied once to a buckwheat field at rates of 0, 20, 40, and 60 Mg ha−1 (BC0: no biochar; BC1: 20 Mg ha−1; BC2: 40 Mg ha−1; BC3: 60 Mg ha−1) for two soil types (aeolian sandy and grey meadow soil) in the northeast of Inner Mongolia, China. The soil water storage (SWS), nutrient contents (organic matter, available nitrogen, phosphorus, and potassium), microbial biomass (carbon, nitrogen, and phosphorus), and enzyme activities (urease, invertase, and alkaline phosphatase) were assessed at a soil depth of 0–15 cm as part of the soil quality assessment, and the buckwheat grain yield was estimated for crop productivity evaluation. The results showed that biochar amendment improved selected soil physicochemical and microbiological properties and buckwheat yields for both soil types. Compared to BC0, the biochar addition increased buckwheat yields, on average, by 11.23% to 22.82% in aeolian sandy soil and by 7.36% to 14.87% in grey meadow soil across three years. The results of principal component analysis (PCA) and random forest analysis (RFA) indicate that soil available nutrients and microbiological properties were the most important factors influencing buckwheat yields in aeolian sandy soil and grey meadow soil, respectively. Based on RFA, the available potassium, phosphorus, and nitrogen were found to contribute at rates of 13.10%, 10.06%, and 8.12%, respectively, to buckwheat yields in aeolian sandy soil. In contrast, alkaline phosphatase, urease, and microbial biomass carbon contribute 20.26%, 8.48%, and 7.82%, respectively, to the buckwheat yields in grey meadow soil. Following biochar addition, there was greater improvement in soil health and buckwheat production for aeolian sandy soil than grey meadow soil. In conclusion, biochar addition is an effective practice for improving soil health and crop productivity in both aeolian sandy soil and grey meadow soil in semi-arid regions.

Long-Range Transport of a Dust Event and Impact on Marine Chlorophyll-a Concentration in April 2023

Dust aerosols serve as a crucial nutrient source to the oceans and profoundly influence marine ecosystems. This study used satellite and ground observations to explore a strong dust event on 9–13 April 2023, emanating from the Gobi Desert, shared by Mongolia and China’s Inner Mongolia region. We investigated the deposition of dust particles and their effects on marine phytoplankton communities. Our findings revealed that the dust event was intense, enduring, and expansive, illustrated by hourly PM10 concentrations peaking at 5055 µg/m3 near the source and consistently exceeding 1000 µg/m3, even at considerable distances. The dust traveled along two different trajectories and was deposited in the same area of the Northwest Pacific. Total dust deposition in the study area (37°N–42°N, 145°E–165°E) was 79.88 mg/m2 from 13 to 18 April, much higher than the 2019–2022 average deposition of 33.03 mg/m2 for the same period. With dust deposition, the observed mean chlorophyll-a concentrations in the area increased to 2.78 mg/m3 on 14 April, an extraordinary 692% increase above the long-term average. These results highlight the profound impact of dust on the productivity of marine phytoplankton communities by inputting more nutrients into the ocean through different pathways.

Mapping livestock density distribution in the Selenge River Basin of Mongolia using random forest

Mapping dynamically distributed livestock in the vast steppe area based on statistical data collected by administrative units is very difficult as it is limited by the quality of statistical data and local geographical environment factors. While, spatial mapping of livestock gridded data is critical and necessary for animal husbandry management, which can be easily integrated and analyzed with other natural environment data. Facing this challenge, this study introduces a spatialization method using random forest (RF) in the Selenge River Basin, which is the main animal husbandry region in Mongolia. A spatialized model was constructed based on the RF to obtain high-resolution gridded distribution data of total livestock, sheep & goats, cattle, and horses. The contribution of factors influencing the spatial distribution of livestock was quantitatively analyzed. The predicted results showed that (1) it has high livestock densities in the southwestern regions and low in the northern regions of the Selenge River Basin; (2) the sheep & goats density was mainly concentrated in 0–125 sheep/km2, and the high-density area was mainly distributed in Khuvsgul, Arkhangai, Bulgan and part soums of Orkhon; (3) horses and cattle density were concentrated in 0–25 head/km2, mainly distributed in the southwest and central parts of the basin, with few high-density areas. This indicates that the RF simulation results effectively depict the characteristics of Selenge River Basin. Further study supported by Geodetector showed human activity was the main driver of livestock distribution in the basin. This study is expected to provide fundamental support for the precise regulation of animal husbandry in the Mongolian Plateau or other large steppe regions worldwide.

The key characters of animal-style art in the Middle and Late Bronze Age

This paper aims to illuminate the archaeological cultures of the Middle and Late Bronze Ages in the neighboring regions of Mongolia. It delves into the phases and chronology of Mongolia’s Bronze Age development, scrutinizing key characters and their symbols in early animal-style art. The artistic expressions stemming from the nomadic way of life are categorized as “animal-style art,” wherein nomads transitioned the characters from two-dimensional to three-dimensional representations a significant and invaluable contribution to the history of global art. The distinctive characters of art from the Middle and Late Bronze Age not only played a central role in subsequent cultures such as Arjan, Pazyryk, Chandman- Sagil, Slab Burial, and Tagar but also evolved in terms of expressive meaning, attaining a heightened level of perfection. In other words, the origins of this distinctive “animal-style art” can be traced back to the 13th century BC in Central Asia, particularly within the territory of present-day Mongolia. Subsequently, it proliferated across the expansive plains of Eurasia, reaching its artistic zenith between the 7th and 3rd centuries BC.

Sand-Laden Wind Erosion Pair Experimental Analysis of Aerodynamic Performance of the Wind Turbine Blades

In the Inner Mongolia region, sand and dust storms are prevalent throughout the year, with sand erosion having a particularly significant impact on the performance of wind turbine blades. To enhance the performance stability of wind turbines and reduce operation and maintenance costs, this study delves into the specific impact of sand-laden wind erosion on the aerodynamic performance of scaled-down wooden wind turbine blades. The experiment conducts vehicle-mounted tests on scaled models of 1.5 MW wind turbine blades that have been eroded by wind-sand flows from different zones, analyzing the changes in aerodynamic performance of wind turbines caused by the erosion. The results indicate that with an increase in the angle of installation, both the overall power output and the wind energy utilization coefficient of the wind turbines show a declining trend. The power outputs of both the partially eroded group and the fully eroded group are unable to reach the rated power level of 100 W. Compared to the uneroded group, the leading-edge eroded group demonstrated higher power output and wind energy utilization coefficients across most wind speed ranges. This finding verifies the possibility that the drag-reducing effect caused by pits from leading-edge erosion has a positive impact on the aerodynamic performance of the blades. It also provides a new research perspective and strong evidence for the study of erosion effects on wind turbine blades and the optimization of their aerodynamic performance.

Sediment DNA Records the Critical Transition of Bacterial Communities in the Arid Lake

It is necessary to predict the critical transition of lake ecosystems due to their abrupt, non-linear effects on social-economic systems. Given the promising application of paleolimnological archives to tracking the historical changes of lake ecosystems, it is speculated that they can also record the lake’s critical transition. We studied Lake Dali-Nor in the arid region of Inner Mongolia because of the profound shrinking the lake experienced between the 1300 s and the 1600 s. We reconstructed the succession of bacterial communities from a 140-cm-long sediment core at 4-cm intervals and detected the critical transition. Our results showed that the historical trajectory of bacterial communities from the 1200 s to the 2010s was divided into two alternative states: state1 from 1200 to 1300 s and state2 from 1400 to 2010s. Furthermore, in the late 1300 s, the appearance of a tipping point and critical slowing down implied the existence of a critical transition. By using a multi-decadal time series from the sedimentary core, with general Lotka-Volterra model simulations, local stability analysis found that bacterial communities were the most unstable as they approached the critical transition, suggesting that the collapse of stability triggers the community shift from an equilibrium state to another state. Furthermore, the most unstable community harbored the strongest antagonistic and mutualistic interactions, which may imply the detrimental role of interaction strength on community stability. Collectively, our study showed that sediment DNA can be used to detect the critical transition of lake ecosystems.

Determining Small Towns’ Status Based on Their Basic Public Service Level. The Case of Mongolia

Small towns are widely recognized as key drivers in rural sustainable development, primarily by offering essential public services to residents in remote areas, thereby playing a pivotal role in promoting rural sustainability. Research endeavors focusing on small towns and rural regions of Mongolia are infrequent, with the majority of existing studies and reports predominantly rendered in the national language. This linguistic barrier significantly impedes the facilitation of international-level research in these areas. The current study is designed to address this gap by conducting a detailed analysis aimed at identifying small towns within local administrative units. This identification is predicated on an evaluation of their essential functions and activities, utilizing national statistical data from 21 provinces across Mongolia. The approach is geared towards understanding the unique characteristics and roles of these towns within the broader context of rural development and governance. The results show that soum centers are the main destination for access to daily necessities, agricultural trades, non-farm employment, basic education, and minor medical treatment for remote rural residents and serve as small towns. The varied functions of small towns are influenced by socioeconomic factors, urban proximity, and infrastructure. The research findings will enhance our knowledge of the functions of small towns within the rural hierarchy in Mongolia.

An Empirical Study on Wind-solar Energy Reserve in Inner Mongolia in the Context of Carbon Neutrality

This study explores the empirical research of wind and solar energy reserves in the Inner Mongolia region within the broader context of carbon neutrality. Through detailed surveys and data analysis of wind and solar energy resources, we comprehensively assess their potential, reserves, and sustainability. Our findings reveal Inner Mongolia’s abundant wind and solar resources, pivotal in advancing carbon neutrality strategies. However, overcoming challenges such as cost, efficiency, sustainability, and grid coordination of energy storage technologies is imperative to fully leverage this potential. Therefore, this paper proposes suggestions for improvement, including technological innovation, planning optimization, and energy coordination measures. These recommendations aim to address current challenges and enhance the utilization of wind and solar resources in Inner Mongolia, providing valuable insights for future energy planning and policy formulation. This study is a guiding framework for promoting sustainable energy development in the region.

Urban Shrinkage from the Perspective of Economic Resilience and Population Change: A Case Study of the Shanxi-Shaanxi-Inner Mongolia Region

With the increasing uncertainty of urban development, urban shrinkage in the rapid urbanization process in China has become increasingly serious. While many studies have explored urban shrinkage from the economic and population perspectives, they often ignore the essence of the phased evolution of economic and population factors. Thus, this study introduces the theory of economic resilience into the field of urban shrinkage and constructs a theoretical method for identifying urban shrinkage by integrating economic resilience and population change to reveal the evolutionary trajectory of regional urban growth and shrinkage. The results show that urban economic resilience and population change in the Shanxi-Shaanxi-Inner Mongolia region (SSIMR) exhibit strong volatility, highlighting the importance of conducting urban shrinkage studies within specific crisis disturbance scenarios. In the context of the “new normal of the economy”, the economic resilience of cities in the SSIMR has significantly declined, and the problem of economic recession is gradually intensifying. The population change trend of cities in the SSIMR is relatively stable, with population loss being a common problem in urban development in the area and its scope and intensity increasing daily. Urban development in the SSIMR is evolving from global growth to widespread shrinkage, with 56.67% of the cities experiencing relative shrinkage, showing a spatial pattern of “western growth–eastern shrinkage”. Factors such as the agglomeration effect, industrial structure, and policy system collectively shape the evolution of urban growth and shrinkage.

Epithermal Gold Discoveries in the Emerging Khundii Metallogenic Province, Southwest Mongolia

Abstract Mineral exploration since 2005 in a previously underexplored region of southwestern Mongolia resulted in the definition of the Zuun Mod porphyry Mo-Cu deposit, followed by discovery of the Altan Nar and Bayan Khundii epithermal gold deposits along with several prospects and advanced exploration projects. These discoveries form the core of the emerging Khundii (“Valley”) metallogenic province, ~50 × 100 km in size, located within a single island-arc terrane of Middle Carboniferous to early Permian age and predominantly within an individual mapped subterrane. The province is situated ~700 km west-northwest of the late Devonian Oyu Tolgoi porphyry Cu-Au deposit in a belt of mid-Paleozoic island arcs that are part of the Central Asian orogenic belt, host to world-class porphyry Cu-Au and epithermal gold deposits that stretch from southern Mongolia to the west, into China, Kazakhstan, and beyond. The Zuun Mod porphyry Mo-Cu deposit (297 ± 4.8 Ma) is hosted by a granodiorite intrusion cut by B-type quartz-molybdenite-chalcopyrite veins with K-feldspar alteration selvages plus disseminated biotite and magnetite. After definition of this deposit, a regional exploration program was initiated in 2009 over 110,000 km2, based on the underexplored nature of the region. Exploration included compilation of existing geologic, geochemical, and geophysical data and interpretation of satellite imagery followed by ground exploration that included stream, soil, and rock-chip sampling and geologic and alteration mapping. The Nomin Tal Cu-Au prospect was discovered in early 2011, and based on the indications from initial soil sampling, a 400- × 400-m soil survey was conducted over the southern part of the exploration license, which identified a Pb-, Zn-, and Au-in-soil anomaly over an area of ~1.5 × ~5.5 km. The first drill hole within the soil anomaly in late 2011 resulted in the discovery of the Altan Nar Au-polymetallic epithermal deposit with veins of coarsely crystalline quartz-adularia (309.7 ± 0.5 Ma) and Ca-, Mg-, Mn-, and Fe-carbonate gangue that host the base metal sulfides. The Bayan Khundii gold deposit was discovered in 2015 as the result of prospecting, ~16 km southeast of Altan Nar. Subsequent discovery of the Khar Mori gold project was announced in early 2021, ~3 km north of Bayan Khundii along a structural trend, and later in 2021 drilling discovered wide zones of disseminated gold at Ulaan Southeast, ~800 m west of Bayan Khundii. The epithermal quartz-adularia-gold veins (336.8 ± 0.5 Ma) at Bayan Khundii have colloform bands with minor pyrite and are enveloped by proximal illite alteration. The epithermal veins and alteration overprint an earlier, unrelated alteration style of residual quartz and pyrophyllite ± dickite ± diaspore-kaolinite. Similarly, residual quartz and pyrophyllite-dickite at Khar Mori are overprinted by epithermal mineralization, including arsenopyrite. At the central Ulaan project, ~3 km northwest of Bayan Khundii, intense quartz-white mica-pyrite alteration is widespread at surface, including tourmaline bodies and local copper anomalies, associated with nearby residual quartz and related aluminosilicate alteration. These alteration styles indicate erosion of a lithocap to its base, exposing K-feldspar and magnetite plus quartz-white mica-pyrite related to the top of a porphyry deposit, as yet only tested by a few scout drill holes. The undated porphyry-related alteration was subsequently overprinted by the gold-bearing epithermal veins after significant erosion.

Effects of Grazing on vegetation in the Gobi desert region of Mongolia

Mongolia is a massive, semi-arid country in Central Asia with a huge territory of 1,500,000 km2, with rangeland making up around 75% of the country's territory. These rangelands have supported herders and grazing animals for millennia. The transition from nomadic to stationary livestock husbandry in Mongolia’s rangeland has resulted in major changes in vegetation communities due to increased livestock numbers. The primary objective of this study is to examine the impacts of grazing on the vegetation of rangelands in the desert steppe ecosystem. The purpose of this study is to examine the impacts of livestock grazing by measuring vegetation standing crop biomass, vegetation cover, and species' richness. The study was carried out in Khanbogd soum (district), Umnugovi aimag, the southern province of Mongolia. To assess the grazing impact, we sampled fourteen winter camps of herders who are members of the four herder groups, who were located at 1000 m and 2000 m from each. In total, we sampled 28 plots in two consecutive years. Our results indicate that aboveground biomass, cover, and species' richness did not differ with increasing distance from winter camps. Similar grazing pressures were shown at 1,000 and 2,000 meters away from the winter camps as well.

Ecological niche shift and suitable area expansion of a globally invasive species Phthorimaea operculella.

Phthorimaea operculella is a major potato pest of global importance, early warning and detection of which are of significance. In this study, we analyzed the climate niche conservation of P. operculella during its invasion by comparing the overall climate niche from three dimensions, including the differences between native range (South America) and entire invaded region (excluding South America), the differences bwtween native range (South America) and five invaded continents (North America, Oceania, Asia, Africa, and Europe), as well as the differences between native region (South America) and an invaded region (China). We constructed ecological niche models for its native range (South America) and invaded region (China). The results showed that the climatic niche of the pest has expanded to varying degrees in different regions, indicating that the pest could well adapt to new environments during the invasion. Almost all areas of South America are suitable for P. operculella. In China, its suitable area is mainly concentrated in Shandong, Hebei, Tianjin, Beijing, Henan, Hubei, Yunnan, Guizhou, Sichuan, Hainan, northern Guangxi, southern Hunan, Anhui, Guangdong, Jiangsu, southern Shanxi, and southern Shaanxi. With increasing greenhouse gas emissions and global temperature, its suitable area will decrease at low latitude and increase gradually at high latitude. Specifically, the northern boundary will extend to Liaoning, Jilin, and the southeastern region of Inner Mongolia, while the western boundary extends to Sichuan and the southeast Qinghai-Tibet Plateau. The suitable area in the southeast Yunnan-Guizhou Plateau, Hainan Island, and the south of Yangtze River, will gradually decrease. The total suitable habitat area for P. operculella in China is projected to increase under future climate condition. From 2081 to 2100, under the three greenhouse gas emissions scenarios of ssp126, ssp370, and ssp585, the suitable area is expected to increase by 27.78, 165.54, and 140.41 hm2, respectively. Therefore, it is crucial to strengtehen vigilance and implement strict measures to prevent the further expansion of P. operculella.

Continuous monitoring of grassland AGB during the growing season through integrated remote sensing: a hybrid inversion framework

ABSTRACT Inverting grassland above-ground biomass (AGB) presents a significant challenge due to difficulties in characterizing leaf physiological states and obtaining accurate ground-truth data. This study introduces an innovative hybrid model for AGB inversion based on the AGB = leaf mass per area (LMA) * leaf area index (LAI) paradigmn in the Ewenki Banner region of Inner Mongolia. The model integrates the PROSAIL radiative transfer model, machine learning regression, LEnKF data assimilation theory, multisource remote sensing, and meteorological data, following a four-step approach. Firstly, we establish LAI and LMA inversion models by combining the PROSAIL model with machine learning techniques. Secondly, data assimilation fuses the PROSAIL-derived LAI with MODIS-LAI. In the third phase, a Random Forest predictive model is developed for LMA estimation. Lastly, the accuracy of the hybrid model is assessed using empirical data. Precision evaluation with ground-truth samples demonstrates that the assimilated LAI and RF-predicted LMA yield the lowest prediction error for grassland AGB (RMSE = 0.0033 g/cm2; MAE = 0.0028 g/cm2). This model framework addresses the challenge of limited prior knowledge in the PROSAIL-AGB prediction model, thereby enhancing the prediction accuracy while maintaining its key advantages: providing continuous observations at high spatiotemporal resolutions without relying on measured sample data.