Western Part Of Inner Mongolia Research Articles

A study of the impact of entrance space on indoor air quality in vernacular dwellings in desert areas during sandstorms

Alxa League, located in the western part of Inner Mongolia, China, frequently suffers from sandstorms. Such dusty conditions result in sharp increases in respirable particulate matter (PM10) concentration in outdoor and indoor environments, posing a significant health risk to local inhabitants. Vernacular dwellings in this area feature a specific floor plan that includes an entrance space to safeguard indoor air quality during sandstorms while being compatible with the local climate. This study utilises CONTAM, a multizone indoor air quality and ventilation analysis computer program, and field measurements to quantitatively evaluate the effectiveness of the entrance space in protecting indoor air quality against ambient PM10 pollution under both dusty and normal conditions. The simulation results reveal that the entrance space can effectively mitigate PM10 pollution in the middle room, lowering the average concentration from 47.0 μg/m3 to 37.5 μg/m3 during dust periods. However, PM10 pollution may increase in the entrance space, reaching an average concentration of up to 70.0 μg/m3. Experimental outcomes align with the simulated results. Given that construction activities exacerbate desertification and frequent sandstorms, the above findings help identify the optimal design strategies for energy-efficient green vernacular dwellings in the targeted desert area, promoting environmental harmony and addressing climate change challenges.

Analysis of the Variability Characteristics and Applicability of SPEI in Mainland China from 1985 to 2018

Drought is one of the most destructive natural disasters in China and can cause serious environmental and socio-economic impacts. Based on monthly precipitation and temperature data from 571 meteorological stations, the Standardized Precipitation Evapotranspiration Index (SPEI) was calculated on a 12-month scale (SPEI-12) from 1985 to 2018 in mainland China, and it was compared with the records of the Bulletin of Flood and Drought Disasters in China to verify its drought monitoring accuracy. Then, run theory was used to explore in depth the spatiotemporal distribution of drought characteristics and trends in various climatic sub-regions. The results showed that: (1) the comparison with the Bulletin of Flood and Drought Disasters in China indicated that the results of SPEI-12 monitoring drought had high accuracy and could identify drought events in mainland China. (2) About 70% of the regions in mainland China experienced droughts more than 50 times, and about 43% of the regions had drought durations of between 100 and 110 months. Nearly 11% of the regions had drought severities of more than 130, which were mainly located in the Northwest Desert (NWC), the southern part of Northeast China (NEC), and the western part of North China (NC). (3) In the past 34 years, the droughts in the Northwest Desert (NWC), the western part of Inner Mongolia (IM), and the Qinghai-Tibet Plateau (TP) showed an aridity trend, while the droughts in South China (SC) and eastern Central and South China (CSC) presented a mitigation tendency. (4) Specifically, the droughts in South China (SC) were more influenced by precipitation, while those in the Northwest Desert (NWC) and Northeast China (NEC) were influenced by temperature and potential evapotranspiration, and the evolution of drought in North China (NC) and the Qinghai-Tibet Plateau (TP) was mainly influenced by soil moisture. The study could provide scientific guidance and a reference for drought response and sustainable development in China.

Spatiotemporal Variations of Drought in the Arid Region of Northwestern China during 1950–2012

There are water resource shortages and frequent drought disasters in the arid region of northwestern China (ARNC). The purpose of this study is to understand the spatiotemporal variations of the droughts in this region and to further estimate future changes. Multiple drought indexes such as the standardized precipitation index (SPI), the standardized precipitation evapotranspiration index (SPEI), and the self-calibrated Palmer drought severity index (SC-PDSI) are used to investigate the temporal and spatial characteristics of the ARNC drought from 1950 to 2012. Our results indicate the following: (1) The drought indexes exhibit significant increasing trends, and the highest drought frequency occurred in the 1960s, followed by a decreasing trend during the next few decades. All four seasons exhibit a wet trend, with a higher drought frequency in summer than in the other seasons. (2) The changes of the drought indexes in the ARNC also exhibit distinct spatial variations, with a wet trend in the subregions of North Xinjiang (NXJ), the Tianshan Mountains (TS), South Xinjiang (SXJ), and the Qilian Mountains (QL), but with a dry trend in the subregions of the Hexi Corridor (HX) and the western part of Inner Mongolia (WIM). (3) There was a major climate variability in the ARNC that occurred in the 1980s, and there were dry and wet climate oscillation periods of 8a, 17a, and >20a.

Семь десятилетий ойратоведения в КНР (1949‒2019 гг.)

Introduction. Historically, the Oirats of China mainly live in the territory of Xinjiang, in the provinces of Qinghai, Gansu, and in the Western part of Inner Mongolia. Some of the Olets (descendants of Dzungars) live in the steppe part of the Emin Gol of the Hulun Buir Aimag of Inner Mongolia, in Fuyu County of Heilongjiang Province, and in Chengdu, Hebei Province. In the modern historical science of China, until the mid-20th century the Oirats were not distinguished from the bulk of China’s Mongols, and, consequently, their history, culture and language were not subjects of individual studies. Only after its formation in 1949, Chinese Oirat studies started gaining visible features as an important part of Mongolian studies and the historical science of China as a whole. At the same time, Oirat studies as a historical direction were created by several generations of scientists of different nationalities (Han Chinese, Mongols, and Oirats themselves). Goals. The article aims to provide a general overview and scientific analysis of the formation and development of Oirat studies in China over the past seven decades (1949–2019), and to identify the historical paradigm of conducted researches and prospects of further development. Methods. The main research method is historical and chronological analysis. Despite Oirat studies have been existing as an integral part of Mongolian science for seven decades, no analysis of its historical development was ever carried out. Results. This work fills the gap and highlights the most important achievements in the study of China-based Oirats’ history and culture. A prominent attention in this study is given to the materials of ten scientific conferences that have the status of ‘all-China’ ones and were devoted to the study of the history and culture of the Oirats, as well as the scientific journal ‘Barayun mongyol sudul’ (‘Journal of Western Mongolian Studies’), which plays an important role in the development and determination of promising areas of Oirat studies. Conclusion. The analysis of Oiratological research over the past seven decades has revealed the historical paradigm of Oirat studies and prospects for their further development.

Hazards of extreme events in China under different global warming targets

ABSTRACT Changes in the frequency and intensity of extreme events affect the risk pattern of risk-bearing bodies and the effectiveness of response measures. Based on future climate scenario data, in this study, we identify global warming periods of 1.5°C and 2°C above pre-industrial levels, and the temporal and spatial patterns of temperature and precipitation in China during the same period, propose a methodology for risk assessment and integrated analysis of extreme events, build a database of extreme events and their hazards in China in the context of climate change, and assess the hazards caused by extreme events (i.e., heatwaves, floods, and droughts) in China under different warming periods. Under the RCP4.5 and RCP8.5 scenarios, global temperatures increase by 1.5°C and 2°C above pre-industrial levels by 2029 and 2026 and by 2050 and 2040, respectively. The warming would be fast in the north and slow in the south, the warming of the Qinghai-Tibet Plateau would accelerate, and the precipitation would increase in the north and decrease in the south, but the trend of the precipitation reduction in the south would be more significant under the RCP8.5 scenario. For 2°C of warming, the hazard index of severe heatwaves in the North China Plain, parts of South China, and the western part of Inner Mongolia would double that of 1.5°C warming. Regional differences in extreme precipitation would increase, especially under the RCP8.5 scenario, the hazard index of severe floods in parts of East China would be about twice that of 1.5°C warming. Under the joint influence of rising temperature and changing precipitation, the drought situation would be alleviated under the RCP4.5 scenario, but it is intensified under the RCP8.5 scenario. For 2°C of warming, the hazard index of severe droughts in some areas would reach three times that of 1.5°C warming. For the integrated hazard of the three types of extreme events, the areas of high and medium hazards would expand, while the areas of low hazard would decrease. For 2°C of warming, the areas of high and medium hazards would be more than half the total area.

Study on the Relationship Between Respiratory Distress Syndrome and SP-A1 (rs1059057) Gene Polymorphism in Mongolian Very Premature Infants.

Aim: To study the relationship between rs1059057 polymorphism of pulmonary surfactant protein A1 (SP-A1) and respiratory distress syndrome (RDS) in Mongolian very premature infants.Methods: Applying the strategy of case-control study, 120 Mongolian RDS very premature infants (58 males and 62 females) in the western part of Inner Mongolia were selected as the case group, and 120 subjects of non-RDS very premature infants (56 males and 64 females) with the same nationality, same sex and similar gestational age were used as the control group. The single nucleotide polymorphism (SNP) site rs1059057 of SP-A1 was genotyped using polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP).Results: Two genotypes, A/G and A/A, were detected at the SP-A1 rs1059057 locus in the western part of Inner Mongolia. In the case group, the frequencies of two genotypes were 53 and 47%, and the frequencies of A allele and G allele were 73 and 27%, respectively. In the control group, the frequencies of the two genotypes were 42 and 58%, and the frequencies of A allele and G allele were 79 and 21%, respectively. There was no significant difference in the genotype frequency of SP-A1 (rs1059057) locus between the case group and the control group (X2 = 3.275, P > 0.05), and no significant difference in allele frequency between the case group and the control group (X2 = 2.255, P > 0.05).Conclusion: The genotypes and allele frequencies of SP-A1 (rs1059057) locus were not associated with the incidence of RDS in Mongolian very premature infants in western Inner Mongolia.

ALKALOHALOPHILIC BACTERIA OF THE FAMILY BACILLACEAE IN THE LAKES OF THE BADAIN JARAN DESERT (CHINA)

The Badain Jaran desert is located in the western part of Inner Mongolia (China) in the Alashan Highland. The investigated soda-salt lakes combine high pH (more than 9) and mineralization (up to 400 g/dm 3 ), where conditions for the development of an alkali-halophilic microbial community are created. The purpose of our work was to isolate and study pure alkali-halophilic microorganisms in the lakes of the Badain Jaran desert. From the accumulative cultures of the cortex salt and the microbial mats of the lakes of the Badain Jaran desert, pure cultures belonging to the family Bacillaceae (the phylum Firmicutes) were isolated and described. With the help of biochemical methods, the ecological and physiological properties of the isolated bacteria were determined. The isolated bacteria exhibit the properties of alkalophiles and obligate alkalophiles and develop at pH 7–10.5, the optima ranging from 9 to 10. With respect to the concentration of NaCl, the strains showed the properties of obligate halophiles and extreme halophiles. With respect to temperature, the isolated microorganisms are mesophiles growing at 10–50 °C, the optimal growth being at 30–40 °C. With respect to the substrates used, the isolated cultures are noted for extensive metabolic activity and, when in their natural habitats, are supposedly active participants of the destruction of organic matter. To study the hydrochemical indicators of water, the following methods were used: atomic emission spectrometry with inductively coupled plasma, ion chromatography and capillary electrophoresis. As a result, it was found that a sodium cation and anions of carbonate, bicarbonate of chlorine and sulphate dominate in the soda-salt lakes of the Badain Jaran desert in a multicomponent composition. The results obtained broaden the notion of the diversity and ecological significance of bacteria in the extreme natural ecosystems of the Badain Jaran desert. The isolated strains are of interest for biotechnology as producers of enzymes resistant to high pH and mineralization.

Experimental investigation of a solar thermal storage heater assembled with finned heat pipe and collective vacuum tubes

A novel solar thermal storage heating equipment that is integrated with several highly efficient solar collecting heat storage units (HSU) that filled with phase-change material (PCM) and combined with finned heat pipe to enhance the heat dissipation process was developed and experimentally studied. Due to its advantages such as compactness, easy integrity, intelligent operation, rapid heat storage and dissipation rates, and higher overall utilization efficiency, it may has extensive applications in near future in green heating of residential or commercial buildings, agricultural greenhouse heating, drying and other temperature control system. The solar radiation intensity, elevation angle of the equipment, ambient air temperature and flow-rate were considered experimentally as operating parameters. And the characteristics of the temperature distribution in different sections of the PCM in the HSUs were analyzed. The heat storage performance was studied at different solar radiation flux and elevation angle and the heat dissipation performance was conducted by changing ambient air temperatures and convective velocities. Experimental results showed that the optimum elevation angle of the apparatus was 60° (when used in July/August in the western part of Inner Mongolia). The more extensive the solar radiation, the higher heat storage capacity and rate of the STHSE were achieved. Higher ambient air velocity and lower temperature could significantly improve the overall heat dissipation performance and efficiency. At ambient air temperature of 18 °C and velocity of 6.0 m/s through the wind tunnel, the overall heat dissipation rate reached 414 W and the overall efficiency of heat dissipation was obtained as high as 97%.

Depositional history, tectonics, and provenance of the Cambrian-Ordovician boundary interval in the western margin of the North China block

Cambrian–Ordovician strata of the North China block, one of China’s main tectonic provinces, are a thick (up to 1800 m) succession of mixed carbonate and siliciclastic sedimentary rocks. Sedimentological, biostratigraphic, and chemostratigraphic analysis of strata that straddle the Cambrian-Ordovician boundary at the Subaiyingou section in the present-day western part of Inner Mongolia (northwest China) indicate the presence of a significant unconformity between mixed carbonate–fine-siliciclastic strata of the Cambrian Series 3 Abuqiehai Formation, and dominantly carbonate strata of the early Middle Ordovician Sandaokan Formation. The latter is a transgressive systems tract with retrogradationally stacked parasequences that include lowstand shoreline quartz sandstone deposits. The Abuqiehai strata have similar sedimentological characteristics to those of the Cambrian Laurentian inner detrital belt, including slightly bioturbated lime mudstone and marlstone/shale, grainstone, flat-pebble conglomerate, and microbialite. The lower part of the Sandaokan Formation records the rising limb of the middle Darriwilian positive isotopic excursion, recognized herein for the first time in the western North China block. A Cambrian-Ordovician unconformity is developed in many successions globally, and our section in Inner Mongolia records a hiatus of similar timing and duration to a regionally extensive unconformity recorded along the ancient northern Indian continental margin. Other parts of the North China block record a hiatus of much shorter duration but show a similar record of input of siliciclastic sediment above the unconformity. We interpret the western margin of the North China block to have been affected by a regionally significant tectonic event that occurred on the northern margin of east Gondwana, the Kurgiakh or Bhimphedian orogeny. The Inner Mongolian region was, therefore, likely an along-strike continuation of the northern Indian margin, in contrast to most recent paleogeographic reconstructions.

First Report of Race Composition and Distribution of Sunflower Broomrape, Orobanche cumana, in China.

Sunflower broomrape (Orobanche cumana Wallr.) is a holoparasitic plant that penetrates the vascular system of sunflower roots, absorbs plant nutrients and water, and thus causes stunting, reduced growth, and severe yield losses (3). To date, seven races of sunflower broomrape (O. cumana) have been identified by using international standard race differential hosts in Bulgaria, Serbia, Romania, Turkey, and Russia (4). However, the race types present in China are unknown. To identify the race composition of sunflower broomrape in China, race differential hosts of sunflower broomrape were received from Dr. Dragan Skoric (Serbian Academy of Sciences and Arts, Novi Sad, Serbia): Line AD66 has no resistant genes; Kruglik-41 contains resistant gene Or1; B-RO-02A has Or2; Record has Or3; LC1002B has Or4; LC1003B has Or5; LC-1093 has Or6, and Race-G-2 has Or7 (1). Eighteen sunflower broomrape samples were collected in August of 2011, 2012, and 2013 from different provinces/locations in China, including Xinjiang (Xinyuan, Shihezi, Tekesi, Beitun, Urumqi, and Yining), Inner Mongolia (Linhe, Xixiaozhao, Wuqianqi, Tuzuoqi, Keyouqianqi, and Aohanqi), Shanxi (Hunyuan, Shilou, Mizhi, and Dingbian), Jilin (Tongyu), and Hebei (Xuanhua). The differential hosts were each inoculated with the seeds of each broomrape isolate that was recovered, as described by Pancenko with minor modification (2). Briefly, two parts of field soil and one part of vermiculite were mixed together and used as potting mix. The mix was inoculated with broomrape seeds at 10 mg of seeds per 100 g of potting mix. The inoculated mix was placed in a 7-cm (diameter) × 11-cm (height) plastic pot to fill two-thirds of the pot volume. Three sunflower seeds were placed on the surface of the mix at an even distance from each other and covered with additional mix. The pots were kept in a greenhouse under a 16-h photoperiod at 10,000 lux of illumination intensity, temperature of 20-25°C, and 40% relative humidity. Forty days after incubation, sunflower seedlings were taken out from the pot and the roots washed with tap water. The number of tubercles was recorded on the root of each differential host. Race types were determined based on the reaction (tubercule formation on roots) of all the standard differential hosts to the test isolate. The results showed that races A, D, E, and G of O. cumana were present among the isolates. Race G was found in Wuqianqi, Xixiaozhao, and Linhe in the western part of Inner Mongolia. Race E was found only in Shihezi of Xinjiang. Race D was found in Aohanqi and Keyouqianqi (eastern part of Inner Mongolia); Xinyuan, Tekesi, Beitun, and Urumqi (northern part of Xinjiang); and Tongyu (northern part of Jilin). Race A was found in Mizhi, Shilou, and Hunyuan of Shanxi province and Xuanhua in Hebei province. Additionally, race A was also found in Tuzuoqi, the middle region of Inner Mongolia. Thus, races A, D, E, and G were the main race types of O. cumana in China. Race D was the predominant race type and had the widest distribution. Race G was the highest level race type in this study but was mainly limited to the western part of Inner Mongolia. This is the first report of race composition and distribution of sunflower broomrape (O. cumana) in China.

Daytime Changes of Leaf Water Potential in 3 Species of Halophytes Measured at 3 Sites in Western Part of Inner Mongolia

Daytime Changes of Leaf Water Potential in 3 Species of Halophytes Measured at 3 Sites in Western Part of Inner Mongolia

Surveying sandy deserts and desertified lands in north‐western China by remote sensing

Sandy deserts and desertified lands (SDDL) cover most of north‐western China, and desertification is a severe environmental issue in this region. In this study, we classify SDDL into mobile, semi‐mobile, semi‐anchored, and anchored classes, and divide the corresponding severity of desertification into four levels: extremely severe, severe, moderate, and slight. Using SDDL databases derived from Landsat TM and ETM images in 1986 and 2000, we discuss the evolution of SDDL and the processes and causes of desertification. The desertified area increased by 16 101 km2 between 1986 and 2000, and most of the desertified land was classified as severely or extremely severely desertified. However, 3437 km2 of SDDL were also rehabilitated during this period. The area of SDDL increased in the Qinghai and Xinjiang regions, and in the western part of Inner Mongolia, but decreased in the Shaanxi, Gansu, and Ningxia regions. The causes of desertification differed among regions, and different measures to control desertification are proposed for the different regions.

Tetraena mongolica Maxim can accumulate large amounts of triacylglycerol in phloem cells and xylem parenchyma of stems

Tetraena mongolica Maxim is a narrowly monotypic genus of Zygophyllaceae found in a very limited area in the western part of Inner Mongolia, China. The plant is called “oil firewood” and its stems and branches are used as fuelwood. As triacylglycerol (TAG) is the main component of the plant oil, the TAG content was analyzed, as were the distribution of oleosomes in different tissues of the stem. This was in order to ascertain whether the term “oil firewood” referred to this storage lipid. Stems of T. mongolica indeed contained high levels of TAG (approximately 46 mg/g of dry matter or DM). The concentration of TAG in phloem (90 mg/g of DM) was much higher than that in xylem (20 mg/g of DM), and semi-thin sections stained by Sudan Black B showed that almost all cells in the phloem contained oleosomes whereas in the xylem, oleosomes were found only in parenchymatous cells. These results suggest that T. mongolica has a high capacity to accumulate TAG in its stem cells.

Bactrian camel foraging behaviour in a Haloxylon ammodendron (C.A. Mey) desert of Inner Mongolia

The Bactrian camel ( Camelus bactrianus ferus) is uniquely adapted to the deserts of China and Mongolia. It was domesticated about 3000 years ago but the wild Bactrian camel is endangered with less than 1000 remaining in China. We observed the foraging behaviour of 10 domestic Bactrian camels (Alashan) in a Haloxylon ammodendron C.A. Mey desert of Inner Mongolia. The Alashan Bactrian camel is one of about four breeds of the species found in the western part of Inner Mongolia. In each season, plant species selection was observed for each camel over three, 10-min periods at morning, noon and night and their primary activities were recorded over a period of 17.6, 19.2, 18.5, and 17.2 h in winter, spring, summer and autumn, respectively. Forage intake was estimated by mimicking bite size for each species and extrapolating to the total time spent grazing. Plant species preferences were calculated from estimates of their relative utilization and availability. The number of species contributing to the camels’ diet in winter, spring, summer, and autumn were 5, 6, 7, and 8, respectively. No seasonal differences ( P < 0.05) were detected in forage intake, faecal output, or apparent digestibility. The Bactrian camels switched their diet from a senesced forb, Agriophyllum squarrosum (L.) Moq., in winter to the shrub H. ammodendron in spring, and to an increasing dependence on perennial and annual herbaceous species in autumn. H. ammodendron was the dominant species in this desert community and was utilized in each season. Camels are dependent on a yearlong forage supply from a fragile environment, which can readily be damaged without careful management.

Ground observations of a strong dust storm in Beijing in March 2002

On 20 March 2002, one of the most intense dust storms of the last decade struck Beijing: the total suspended particle (TSP) mass concentrations during the event reached 12 mg/m3 and the visibility was reduced to less than 200 m. Variations in meteorological conditions in the boundary layer were monitored during the event, and changes in the physical properties and chemical composition of the aerosol also were studied. The dust storm was accompanied by a sharp and distinct increase in wind speed, a decrease in relative humidity, and increased mixing in the boundary layer due to turbulence. Back trajectory analysis and meteorological analysis showed that the main sources of dust particles that affected Beijing were most likely in southern Mongolia and the western part of Inner Mongolia, China. The amounts of Mg, Al, K, Ca, Ti, V, Cr, Mn, and Fe relative to one another were similar for the dust storm and nondust storm samples, and these elements occurred in near‐crustal proportions. In contrast, both the concentrations and enrichments relative to the crustal reference material for other elements, such as Se, Ni, Pb, Br, and Cu, were much higher during the dust storm than before or afterward. These elements, which are often associated with pollution emissions, apparently originated from distant sources upstream as well as from local sources in Beijing. Even though their enrichments were lower during the dust event, the concentrations of S, Zn, and Cl during the dust storm were higher than in the nondust periods; these results are further evidence that dusty air often contains higher levels of pollutants than nondusty air.

Evidence for a warm-humid climate in arid northwestern China during 40–30 ka BP

Former shorelines and sedimentary records from several lake basins in northwestern China (Xinjiang, Qinghai) give evidence for warm and humid climatic conditions during 40–30 ka BP. Further indications of this favorable climate period are derived from palaeosols from the Ili loess and from cemented calcareous layers on the terraces of the Keriya River at the southern margin of the Tarim Basin and in the Badain Jaran Desert in Inner Mongolia. At that time, annual mean temperature in the Qaidam Basin was 2 °C higher and in the western part of Inner Mongolia even 2–3 °C higher than today. Precipitation in most parts of northwestern China was between 60–300 mm greater than today. These changes were probably a consequence of an increase in ocean surface temperature and evaporation resulting from a higher radiation input at middle and low latitudes caused by changes in the Earth's precessional cycle. As a result of these orbital changes, it is suggested that the intensified westerly circulation was responsible for increased moisture over northwestern China.

The 5000-year environmental change and associated human activities at Sokho-nor Lake, Inner Mongolia, P.R. China

Sokho-nor Lake is situated in the western part of Inner Mongolia, Northwest China. Human beings have been living in this area since the New Lithic Age. Throughout history, this area has undergone repeated desert-oasis periods, associated with changing river inputs through time. The varying population in the area has been strongly influenced by the water resources available. Inhabitants included members of the Han race and people from northern nomadic tribes. Their activities in the past were affected by changing lake levels. Today, the lake is completely dry, and the environmental impact on the region is a serious problem.

Regional geochemical surveys in arid and semiarid regions in the middle and western part of Inner Mongolia

For many years the results of regional geochemical surveys in arid and semiarid regions of China were not satisfactory. Therefore, we selected eight areas in the middle and western part of Inner Mongolia and the northwestern part of Gansu Province to study this problem from 1982 to 1985. The contents of our study include: the migration and distribution of elements in an arid environment; the interference of aeolian sand; the applicability of different sampling mediums; and the development of effective sampling techniques. Pilot surveys were carried out covering several hundred or more than a thousand square kilometres in every test area after the orientation study. Very good results were obtained in the surveys carried out in mountainous and hilly regions. The only problem was to eliminate effectively the interference of aeolian sand. To accomplish this we collected elastics of −5 ∼ + 2 mm or − 10 ∼ + 0.9 mm coarse grain size in the dry valley. In the stony Gobi desert region and the eroded peneplain region, a rock survey and residual soil survey produced the results expected. However, we had to consider the following influencing factors: (1) the caliche in the loose soil layer forms a barrier, hindering the migration of most of the elements in a vertical direction. Only where the caliche was rather thin was the influence of little significance; (2) in the residual soil of the background area and non-mineralized zone, almost all trace elements are enriched secondarily. The enrichment factors are generally between 1.3 and 1.8. In the residual soil of the mineralized zone, almost all ore-forming elements are impoverished. The well-water geochemical survey and the deep-root system plant survey have a peculiar function in finding ore deposits in the arid region. These two methods are discussed elsewhere.