On the basis of field survey， Ground-penetrating radar （GPR） was used to detect the internal structure of vegetation linear dunes in the southeastern Gurbantunggut Desert， and radar facies image information was obtained. Combined with regional natural geography and morphological characteristics， the evolution model of vegetation linear dunes internal structure was preliminarily discussed. The results indicate that： （1） GPR reveals the shallow （3-5 m） structure information below the dune surface， which can identify high-angle dipping， convex and wedge cross-bedding in the middle-upper part of dunes and crest， and sub-horizontal to low-angle dipping bedding in interdunes and the middle-lower part of dunes， which reflects the strong wind erosion and deposition activity in the upper part of dune， and the accretion in the middle-lower parts of dune wings and interdunes. （2） From desert edge to the center， the shallow sedimentary structure assemblage of dune slope changes from asymmetrical to symmetrical， the dune cross-section morphology showed the same variation， but no evidence of lateral dune migration have been found. （3） According to different scale dune structure sequence， the evolution mode could be divided into four stages： shrub dunes， shadow shrub dunes， longitudinal dune chains and vegetation linear dunes. With the continuous merging and integration of overlapping shrub dunes， the width and height of linear dunes increase， frequent wind activity at the dune crest， and the types of high-angle dipping， convex and wedge cross-bedding increase. （4） The causes of massive bedding （below 3-5 m， not hit the bottom） and GPR signal attenuation should be further verified. Besides， to systematic clarify the evolution process of vegetation linear dunes in study area， it is necessary to supplement more GPR data and chronology study.

Desert inverted channel is a special river-liked positive landform in arid land， which contains information of significant environmental change that results in riverbed revising. Following the geomorphology law， this study investigated desert inverted channels around the world based on the published literature and our field observation. We summarized its spatial distribution， morphological characteristics， material composition， sedimentary structure and formation mechanism. Generally， inverted channels developed in the main sand seas around world. Its surface is composed of debris or cemented materials， subsurface consist of sandy-clay materials with a relatively soft texture. Due to the differential erosion of the sediments in the riverbed and riverbank， the riverbed is relatively elevated. Although some progress has been made in the study of deserts inverted channels on Earth， further research needs to be carried out in terms of their formation age and climatic significance. Meanwhile， more studies should be carried out to compare with the different types of inverted channels on Mars. This will provide important basis for revealing the hydrological activities and environmental changes on Mars.

The grain size composition of dunes is mainly determined by wind regimes， sand sources， and the interaction between dune morphology and airflows. The grain-size composition of sand dunes can reflect the formation process of different types of dunes. Samples were collected from 0-5 cm of the surface layers at the foot of the windward slopes， the dune crests， and the foot of the leeward slopes of 20 barchan or dune chains and 25 parabola dunes in the Mu Us Desert. The grain-size composition of the samples was tested and analyzed to explore their grain size characteristics. The results show that： （1） There are no significant differences in grain-size composition and parameters between barchan dunes and parabola dunes， and the grain -size frequency distribution curves are typical single-peak shapes， but compared with barchan dunes， the parabolic dunes have worse sorting and higher suspended components； The windward slope of parabola dunes has worse sorting and higher coarse sand content than barchan dune. （2） In the statistics of grain-size distribution patterns of sand dunes， the barchan dunes tend to have the finest grain-size on the windward slope， accounting for 65%， whereas the parabolic dunes tend to have the finest grain-size on the leeward slope， accounting for 56%；The grain-size frequency distribution curve also indicated the biased results of the grain-size distribution patterns. （3） Vegetation， the opposite morphology of barchan dunes and parabola dunes and their interaction with airflows are the main factors that cause the differences in grain-size characteristics between the two types of dunes.

The main supply of soil water comes from precipitation， which determines the changes of soil water patterns spatially and temporally in arid and semi-arid areas. Precipitation also plays a key role in the supply of soil water at different soil depths in sandy areas. In this study， the hydro 1D model with optimized parameters was used to analyze the variation characteristics of soil water leakage at different depths of 10， 30， 50， 70， 90 and 110 cm in the mobile dunes of Mu Us Sandy Land and its response to different rainfall patterns. The results showed that the amount of soil water leakage was different at different soil depths in mobile dunes from May to September. The amount of water leakage decreased along the increase of the soil depth from May to August. The amount of water leakage increased along the increase of the soil depth in September. The changes of water leakage was consistent with precipitation. The maximum water leakage occurred in August， that the amount of soil water leakage was 148.51 mm at the depth of 110 cm， accounting for 67.5% of the monthly precipitation. The maximum leakage rate and the maximum leakage amount accompanied with large rainfall events. The amount of rainfall and the initial soil water content jointly determined the soil water leakage rate and duration. The soil water will infiltrate to 110 cm when the rainfall reached to 14.8 mm， and the cumulative leakage reaching the maximum leakage rate is 1.89 mm， accounting for 13.69% of the precipitation. Continuous precipitation events are conducive to recharge the deep water， and they shorten the time when the leakage rate reaches the peak in each soil layer Our results from the estimation of soil water leakage in sandy soils could provide theoretical basis in the assessment of water resources and water demand for ecological construction in arid and semi-arid regions.

The arid and semi-arid regions cover more than half of China's land area， which are sensitive to global climate change and human activities with fragile ecological environment. Extreme climate events are frequent and strong in those regions， where the climate anomalies are not only modulated by the internal atmospheric variability， but also affected by the underlying surfaces such as sea surface temperature， sea ice and snow cover. These physical factors play a key role in the climate anomalies in arid and semi-arid regions. This article systematically reviews and sorts out the effects of these physical factors on climate anomalies in arid and semi-arid regions of China. Studies have shown that atmospheric teleconnection is an internal influencing factor of climate anomalies， and the circulation anomalies caused by its phase transition will cause climate anomalies in arid and semi-arid regions by regulating the position of jet stream， planetary wave activity， blocking intensity， and the location of trough-ridge. Sea surface temperature affects the climate anomalies in arid and semi-arid regions by influencing the intensity of monsoon and Walker circulation and the location of western Pacific subtropical high， in the meantime stimulating the response of atmospheric Rossby waves. Moreover， snow cover changes the thermal conditions of the underlying surfaces such as surface radiation and soil temperature and humidity through the albedo effect and hydrological effect， and then has a significant effect on the temperature and precipitation in arid and semi-arid regions by diabatic heating or changing atmospheric baroclinicity. On the basis of summarizing the existing research progresses and achievements， the paper points out that the synergistic mechanism among different factors and the contribution of each factor to the climate anomalies in the arid and semi-arid regions of China still need further research.

According to the requirement from the First National Conference on Combating Desert in November， 1958， the Chinese Academy of Sciences organized rapidly the Scientific Investigation Team for Combating Deserts （SITCD， CAS） in the January， 1959 and carried out fieldwork soon， which was the maximal national desert comprehensive survey up to now with the widest areas， the most complete majors， the most diverse team members， and the most concentrated campaigns. This paper， as the pioneering part （1） of the practice on prevention and control of aeolian desertification and the development of desert science in China for 70 years， briefly retrospect the results and experience from a smaller scale desert survey in 1957 and 1958， which was cooperative implemented by Chinese Academy of Sciences and Academy of Sciences of the USSR， and talk over the achievement and positive impacts from the desert comprehensive survey of the Scientific Investigation Team for Combating Deserts， Chinese Academy of Sciences in 1959. Based on the references and available data， every Investigation Team Branch for different desert and Gobi in Northern China had reported the progression of field-survey and the analysis and research mostly focused on the distribution of deserts/Gobi， different genetic types， sand material source area， hazards of sand blown， desert control measures， socioeconomic status， agriculture， forestry， and animal husbandry production. We also specially discus and praise highly the followings milestone events such as （1） the pioneering and development of desert science is the practiced paragon of “task promoting subject development”， （2） “national demand is our first choice” radiated the scientist’s enthusiasm and dedication spirit during 1950s， （3） professional selection and prominent contribution of 8 distinguished scientists， and （4） the international cooperation assisted development of desert science in China.

In recent years， with the rapid expansion of highway construction area in China， some problems about wind force disasters on highway have appeared under special environmental conditions， which seriously threaten the safety of highway traffic. The compound disaster of snow drift and blown sand on Kete Highway in Altay Prefecture of Xinjiang just is a special seasonal wind-driven disaster. It is found that the occurrence of this kind of disaster is related to the regional disaster-pregnant environment with the reginonal east gale and abundant sand & snow sources in winter， as well as the layout of sand control system， the configuration of subgrade section and the artificial disturbance such as sand or snow stacking. In accordance with the principle of adapting measures to local conditions， fortifing against harm， complying with nature and addressing both symptoms and root causes， strengthening protection ability， and linking mechanical control with plant control have been formed in order to comprehensively control the blown sand disaster in spring and sand-snow compound disaster in winter. A comprehensive treatment scheme of road side terrain leveling， resistance-solid-transport structure protection system construction and later scientific management and protection has been formulated. This research results can provide a scientific plan for the disaster prevetion of Kete Highway， and also provide a reference for similar disaster control in other areas.

Desert is one of the important terrestrial ecosystems in Northern China and covers 1/5 of the land of China. Plant community is an important part of the desert ecosystem， which has important implications for the enhancement of Northern Ecological Shelter Zone， and for the implementation of state key ecological projects， as well as for the Belt and the Road Initiative and economic-social development. The surveying zone includes Tarim-Jungar basin deserts， Qinghai-Tibet Plateau desert， Alax-Hexi Corridor desert， West Edos and North-to-Yinshan desert， and semi-arid desert-like sandy lands in the middle and eastern Inner-Mongolia. A total of 2 300 sample sites were set up systematically to investigate vegetation types， species composition， spatial distribution， and habitat attributes of desert plant communities across northern China. There were 8 300 plant specimens， 50 000 habitat parameters， and 2 300 DNA bar-codes obtained in the present study. On this base， a report on the desert plant community types， characteristics and status， and the atlas of distribution of desert plant communities will be compiled， as well as a monitoring system will be built for future long-term surveying. The data supporting the above report， atlas， and monitoring system will be pooled into a data bank of the major desert plant communities in China， being shared through the National Cryosphere Desert Data Center （NCDC）. This project and the output will provide solid support for combating desertification， plant conservation and sustainable development in the northern part of China.

At present， there is a lack of comprehensive understanding of the surface flow patterns over barchan dunes， especially the complex flow structure in the vortices zone， and thus further research is needed on the influence of morphological characteristics and flow velocity on the flow structure of barchan dunes. In this paper， the airflow characteristics over the surface of barchan dunes under different geometric parameters and different inlet velocities were studied using the CFD （Computational Fluid Dynamics） numerical simulation and the RNG k-ε turbulence model， focusing on the flow characteristics of the leeward side vortices zone and the relationship between its range and the geometric parameters of the dunes and the inlet velocities. The results show that： （1） The higher the height of the barchan dune， the larger the length of the wake vortices zone is， approximately 5-7 times the height of the dune. （2） The greater the gradient of the windward slope of the barchan dune， the greater the length of the wake vortices zone is， approximately 5-7 times the height of the dune. （3） The influence of inlet velocity on the position of the reattachment point is quite limited， and the length of the vortex zone caused by different inlet velocities is about 6-7 times the height of the dune， suggesting that the larger the inlet velocity is， the shorter the length of the wake protected zone and the smaller the disturbance of the dune on the flow can be found. This study comprehensively analyzes the shaping effect of the flow patterns on the shape of barchan dunes and further confirms the cause of the formation of small barchan dunes on the downstream of the horns of the upwind barchan dunes. Collectively， the current results can deepen the understanding of the evolution mechanism of barchan dune formation， and enrich the basic theory of aeolian geomorphology.

Chemical measures， engineering measures and biological measures are called the three major sand control measures. The application and development of chemical sand fixation measures are strictly constrained by materials， and there is a trough period in the development of sand control technology. In recent years， with the development of materials science， inorganic， organic and inorganic organic composite chemical new materials have been widely used in the field of sand control， and chemical sand fixation measures have become a research hotspot. Sand fixation materials with low cost， high efficiency and good biocompatibility have become the key of chemical sand fixation technology， and environmental protection is the primary restrictive factor in the selection of materials. This paper summarizes the research progress of environmentally friendly sand fixation materials processed from natural materials， classifies environmentally friendly sand fixation materials， and analyzes the problems existing in the development of chemical sand fixation and the necessity of environmentally friendly sand fixation materials. This study will provide a theoretical basis for the development of high-performance environmental friendly chemical sand fixation materials.

The Qinghai-Tibetan Plateau （QTP） is a unique physiographic region with the highest elevationof in the world. It is known to have a significant impact on local， regional， and even global weather and climate systems. Based on observational data from meteorological stations， here we review variation characteristics of average and extreme precipitation and associated influencing factors in the QTP since 1960. Results show that annual average precipitation throughout the Tibetan Plateau has increased over the past 60 years， with variation rates ranging from 3.8 mm to 12.0 mm/decade， but its significance level is disputed. Precipitation has increased significantly in winter and spring， being highest in spring， while no obvious precipitation change has been observed in summer and autumn. At a regional scale， precipitation in the Three Rivers' Headstream Region exhibited an increasing trend， with a variation rate between 7.3-20 mm/decade. Annual mean precipitation in the Yarlung Zangbo River Basin did not exhibit an obvious increasing trend， with a changing rate between 0.4-9.0 mm/decade. Precipitation in the Qilian Mountains increased significantly， with a variation rate between 1.0-13.2 mm/decade. The average annual precipitation rate was 1.9-3.3 mm/decade in the Qinghai Plateau， 12.5 mm/decade in the Tibetan Plateau， 6.7-8.6 mm/decade in the Qaidam Basin， and 7.2 mm/decade in the Gonghe Basin. Extreme precipitation events and the number of extreme precipitation days have increased significantly throughout the QTP， and the spatial heterogeneity of extreme precipitation changes has been significant. Many factors have been shown to affect precipitation change throughout the QTP， including large-scale atmospheric circulation factors， plateau surface conditions， and climate warming. Further researches should use more types of data sources to monitor precipitation changes throughout the QTP， especially precipitation changes at regional or watershed scales， and to further improve the mechanism research of precipitation changes over the QTP.

Plants respond to and adapt to environmental changes by adjusting biomass allocation of various organs. Biomass allocation represents plant growth strategies and the functional trade-offs between components. In this study， biomass and allocation characteristics of each component in different types of soils were compared and analyzed， as well as allometric relationship， to explore the survival strategy of Agropyron mongolicum var. mongolicum. The results showed that there were significant differences in the biomass of each component among sierozem soils， dark loessial soils and aeolian soils， which showed stem > root > leaf > inflorescence； and the biomass allocation pattern of components was similar， which showed storage module > vegetation module > reproductive module. Different soil types had no significant effect on the total biomass， but significantly affected the biomass allocation ratio of most module biomass， such as， stem， root， inflorescence， vegetation， storage and reproductive module of A. mongolicum var. mongolicum. The vegetation module of A. mongolicum var. mongolicum in aeolian soils was significantly lower than that in indark loessial soils and sierozem soils， while the storage module was significantly higher than that in dark loessial soils and sierozem soils. The reproductive module ratio of dark loessial soils and aeolian soils were significantly higher than that of sierozem soils. Soil pH and electrical conductivity were the main factors affecting root-shoot ratio， biomass ratio of storage/vegetation， reproductive/vegetation and reproductive/storage of A. mongolicum var. mongolicum； available potassium， pH and electrical conductivity were the main factors affecting the biomass ratio of leaf/stem， leaf/root， leaf/inflorescence， root/inflorescence， root/stem and stem/inflorescence. The relationship among module biomass or between plant height and module biomass are mainly characterized by allometric relationship which was different among different soil types.

The effect of dust storm on human living and production do not speak for themselves. Dust storm occurrence days decreased in recently 70 years， but it had been obviously increased since 2021， and attracted a lot of attentions. However， all the published papers were based on simulation or dust geochemistry， and almost no field data. We used field measurement of sand transport， PM₁₀ concentration and transported aeolian sediment grain size to explain the dust hazard in the dust sources during a strong dust storm. Our results indicated that： （1） Wind velocity was much larger in the dust sources than national weather station data. （2） PM₁₀ concentration can reach to 100 mg·m^-3， and is also larger than national measured data. （3） Sand transport reached to 10 kg·m^-1·h^-1， and dust can be transported longer distance. （4） The mean grain size of transported aeolian material was 0.07 mm， and coarse sand frequency can reach to 9%， and PM₁₀ frequency can reach to 8%. Coarse sand impacted on erodible land surface and caused more dust come into air and supplemented dust concentration in the sources. （5） Sand transport rate increased about 2 times， PM₁₀ concentration increased 2.90 time， and PM₁₀ frequency increased 1.29 time on disturbed land surface than undisturbed land surface， which means that protected gobi land surface can greatly decreased dust material during dust storm.

The characteristics of regional sandstorms in Northwest of China from 2000 to 2020 were analyzed using ground observation data， and based on climatic dynamic factors， temperature， precipitation and NDVI data to analyse the causes of regional sandstorms changes in Northwest of China. The study results show that from 2000 to 2020， the annual total number of days of regional sandstorms in Northwest of China showed a fluctuating downward trend， and there were two high （low） frequency periods. Spring is the season of high incidence of regional sandstorms， of which the total number of days in April is the highest， reaching 47 days. Compared with the first ten days and the middle ten days of the month， regional sandstorms are more likely to occur in the last ten days of each spring months. The Tarim Basin in southern Xinjiang and central-western Inner Mongolia and the Hexi in Gansu are frequent areas of regional sandstorms in Northwest of China with total number of days more than 10 days， and the total number of days in most other places of Northwest of China is less than 8 days. The area index and intensity index of the polar vortex in the northern hemisphere and the polar vortex intensity index in Asia have a significant positive correlation with the number of days of regional sandstorms. The transition of the northern hemisphere polar vortex from an expansion period to a contraction period and the weakening of its intensity are important climatic dynamic factors for the reduction of regional sandstorms in Northwest of China. The annual （spring） precipitation and average NDVI in Northwest of China are significantly negatively correlated with the number of days of regional sandstorms. In the past 21 years， the climate in most parts of the northwest region has tended to be warm and humid， and the vegetation cover has improved as the main trend. The transformation is conducive to the shrinkage of the desertified area and reduces the occurrence of non-imported sandstorms.

Badain Jaran desert and Tengger Desert are the second and third largest mobile deserts in China. The dynamic monitoring of barchan dunes in the joint zone of the two deserts can reveal the formation and evolution law of dunes in this area， and provide scientific support for the study of aeolian geomorphology development in the joint zone of deserts. The barchan dunes in the joint zome of Badain Jaran Desert and Tengger Desert were monitored by Google Earth high-resolution historical images， and the dune migration rate and morphological changes in this area were analyzed. The results showed that the average migration rate of dunes is 5.88-19.55 m?a^-1 in the study area， with an average of 10.03 m?a^-1. The moving direction of sand dunes ranges from 109°to 135°， and the average moving direction is 122°. During the dune movement， the dune morphological changes are more complex. Before and after the movement， except for the reduced height of the sand dunes， the length， width， perimeter and basal area and the windward slope of the barchan dunes generally tends to increase. Wind regime provides dynamic conditions for dune movement. The moving direction of sand dunes is consistent with resultant drift direction. The wind direction in the study area is mainly NW and WNW， and the migration rate of south arm of barchan dune is significantly higher than that of north arm due to the influence of WNW direction sand transport. In addition， the dynamic change of dune is also controlled by the morphology of dune itself. There is a significant negative correlation between dune migration rate and dune morphology parameters （windward slope length， height， width， perimeter and basal area） in the study area （P<0.01）. The difference of vegetation cover and dune density leads to the difference of dune migration rate. Before and after dune movement， the variation of morphological parameters is complicated. The variation of sand source richness and the change of dune shape caused by interdune shrub are the main reasons for the complexity of dune shape change. The annual sand transport flux of the sand dune junction belt is 170-521 t?m^-1， the average of the annual sand transport flux is 301 t?m^-1.

The global environment has undergone profound changes since the industrial revolution. Due to the poor stability， anti-interference and self-recovery abilities of ecosystems， global change has led to the decline of natural resource supply capacity， land degradation， biodiversity reduction， frequent disasters， and increased ecosystem risks in ecologically vulnerable regions. Therefore， it is urgent to implement researches on global change risk in ecologically vulnerable regions. This study mainly summarized the researches on the risk sources and the impact of global change on ecologically vulnerable areas of China， as well as the response to global change. The study then put forward the future strategies for global change to promote the in-depth understanding of the response of ecosystem to global change and improve the ability to cope with global change in typically and ecologically vulnerable regions of China. The risk of global change in ecologically vulnerable regions comes from the impact of environmental change on complex systems of natural， social， and economic. Global change has a great impact on the ecosystem of ecologically vulnerable regions， with climate change as the main symbol and human activities as the main driving force. Global change causes extreme climate events， frequent disasters， land degradation， the reduction of vegetation productivity and biodiversity， the melting of glaciers and frozen soil， and the change of water resources pattern， which may intensify under the continuous impact of global change in the future. However， the implementation of ecological construction project has significantly improved the ecological environment. In the future， we should strengthen the researches on the coupling of natural， social， and economic systems， the monitoring of resources and environmental factors， and the risk assessment and early warning of global change.

As an important synoptic and climate index， diurnal temperature range （DTR） reflects the extreme temperature difference between day and night. Compared with average temperature， DTR is more sensitive to changes in surface radiation budget and has important reference value for environmental changes and climate anomalies. The physical process of dust aerosol and its climatic effect are important factors affecting the lithosphere-atmosphere-ocean system， but the influence of dust climate effects on DTR has not been studied. The study reveals the climatic impact of dust aerosol on DTR over East Asia during 2002-2005 based on the WRF-Chem model （Weather Research and Forecasting coupled with Chemistry）. The results show that the WRF-Chem model can well reproduce the spatial-temporal distributions of meteorological field and dust aerosol over East Asia. The dust climate effect dominated by direct radiative forcing leads to the decrease of DTR in most parts of East Asia continent. During daytime， the direct radiative effect induced by dust heats the atmosphere and cools the surface， contributing to net surface radiation-cutting， thus further the decrease of the maximum Temperature and DTR. In contrast， an opposite variation tendency of DTR， primarily regulated by dust indirect effect， occurred over the Tibet Plateau and the northeast of China due to reduction of snow cover and liquid water path， respectively.

The DPSIR model and spatial econometric method are used to measure and study the temporal and spatial evolution of high-quality green development in the Yellow River Basin. The results show that： （1） The level of high-quality green development in the Yellow River Basin shows a steady improvement trend， but the whole is in the primary stage. During the past 20 years， it has steadily increased at an average annual rate of 3.32%， and the internal driving force and response have contributed significantly. The development of pressure， state and impact needs to be improved. （2） There are significant differences in the level of high-quality green development among provinces along the Yellow River， but the high-quality green development level of each province shows an increasing trend. （3） There is spatial autocorrelation in the level of high-quality green development in the Yellow River Basin， but this correlation is gradually weakening， and there is no spatial agglomeration characteristic with distribution along the Yellow River. The spatial agglomeration center of high-quality green development in the Yellow River Basin has shifted from Sichuan Province （1999） to Inner Mongolia Autonomous Region （2019）， and has not yet formed a spatial agglomeration group of a certain scale.

Using two-year-old Populus euphratica seedlings as test materials， the study of P. euphratica under different salt stress （0， 100， 200， 300， 400 mmol·L^-1 of NaCl） and different drought stress （0， 7， 14， 21， 28 day） was conducted. The results showed that：In terms of the antioxidant enzyme system， with the increase of salt stress and drought stress， the activities of protective enzymes SOD， POD and CAT increased first and then decreased. The reaction speed and duration of different protective enzymes were different in response to drought stress and salt stress. The protective enzymes of P. euphratica were comprehensively regulated to form the defense function of the whole antioxidant enzyme system. As for the osmotic regulation system， with the increase of salt stress and drought stress， the content of soluble sugar continued to increase， and the response speed and duration of its accumulation to different levels of salt stress and drought stress were different. The osmotic balance was maintained by the continuous accumulation of organic matter to form the long-term protection function of the osmotic regulation system. In the cell membrane system， with the increase of salt stress， MDA content first decreased and then slowly increased， basically maintaining a low level， while with the increase of drought stress， MDA content continued to increase. Under salt stress and mild drought stress， P. euphratica can maintain the integrity of cell membrane structure and function through adaptive regulation to realize the protective effect of the cell membrane system. Under salt stress and drought stress， the antioxidant enzyme system， osmotic regulation system， and cell membrane system were adapted to enhance the salt tolerance and drought resistance of P. euphratica. The study on physiological response of P. euphratica to salt stress and drought stress is of great significance for the cultivation and recovery of the seedlings in the lower reaches of the Heihe River.

Dust emission in soil wind erosion is one of the core topics in international aeolian research， which develops rapidly in recent years， but the introduction of its research progress is not systematic and comprehensive. This paper combs the research history of dust emission in soil wind erosion at home and abroad， divides the research stages for the first time， refines the main research results of each stage， and introduces some new understandings of the dust emission mechanism. Based on the reclassification of dust emission models， the model establishing process， advantages and disadvantages of various models and their applications in global and regional dust models are introduced. This paper puts forward some hot and difficult issues in the current dust emission research， hoping to provide some reference for relevant scholars to carry out research work in this field.

It has attracted extensive attention that the climate in the arid region of Northwest China is warming and wetting， but further research is needed on the magnitude， trend and spatial performance of this phenomenon. The Hexi Corridor is located in the eastern part of the arid region in China， which is an important area along "the Belt and Road". In this paper， 7 meteorological stations in Wuwei， Minqin， Yongchang， Zhangye， Linze， Gaotai and Jiuquan respectively， located in the plain area of Hexi Corridor， were selected to analyze the characteristics of temperature and precipitation change from 2000 to 2020. The results show that the average temperature has increased by 0.53 ℃/10yr， representing a decreasing trend from east to west； the change rate of average maximum temperature is 0.22 °C/10yr， and the change rate of average minimum temperature is 0.40 °C/10yr. There is no significant change trend in annual precipitation during 2000-2020， but the interannual fluctuation of year rainfall increases. The annual precipitation of <5 mm，5-10 mm， 10-15 mm， 15-20 mm， and >20 mm is 58.8 mm， 38.3 mm， 22.1 mm， 12.7 mm， and 16.1 mm respectively； and each level of precipitation accounts for 39.69%， 25.87%， 14.93%， 8.60% and 10.90% of the annual precipitation. In the past 20 years， the frequency of different precipitation events， their contribution to precipitation， and the number of precipitation days did not change much. The temperature increase in the eastern part of the Hexi Corridor was larger than that in the western part， but the change in precipitation did not show a difference between the eastern part and the western part. Overall， the climate of the Hexi Corridor had a trend of warming in the past 20 years， but the trend of wetting is not obvious.

Focused on the variation of particle size characteristics of surface sand before and after sandstorms in the Taklamakan Desert hinterland， we conducted a systematic particle size analysis of surface sand， including parameter calculation， particle size component separation and function fitting. The results show that： （1） The average particle size of the surface sand sample is 143 μm， dominated by fine and very fine sand， which together accounted for 87.02%； after the sandstorm， dominated by very fine sand and fine sand， which together accounted for 79.44%. （2） The average particle size of the sandstorm sample is 82 μm， dominated by powdery sand and very fine sand， which together accounted for 80.89%. （3） After the sandstorm， the average particle size of the surface sand decreased by 46 μm， and the content of clay， powder and very fine sand increased， indicating that the large amount of fine-grained material carried by the dust storm had an important influence on the particle size characteristics of the surface sand. （4） The variation of sand particle size with height is mainly controlled by wind speed， with wind speed thresholds ranging from 7.7 m·s^-1 to 8.4 m·s^-1. In three-dimensional space， the second-order polynomial surface model can well fit the function relationship between the average sand particle size and the average wind speed.

Sedimentary records of the late Quaternary preserved in the deserts are important archives to reconstruct the paleoclimate and paleoenvironmental change. In recent years， different dating methods have been used to establish chronologies of aeolian and lacustrine sediments in the deserts， especially the Optically Stimulated Luminescence （OSL） dating technology. However， it still has some uncertainties whether the luminescence dating techniques could provide reliable ages for relatively young samples. In this study， several sediments were collected from different sites in the Tengger Desert， and their ages were measured by quartz SAR-OSL and K-feldspar pIRIR₁₅₀ dating methods. A set of tests， such as the dose recovery， fading and residual tests， were carried out to explore the applicability and reliability of the K-feldspar pIRIR₁₅₀ dating protocol in this area. The results suggest that the K-feldspar samples were well bleached before deposition. Residual doses of pIRIR signals are between 0.07-0.27 Gy and the dose recovery ratio is basically equal to 1 within the dose range of 60 Gy （equal to about 20，000 years）. The corrected K-feldspar pIRIR₁₅₀ ages are generally overestimated， while the uncorrected pIRIR₁₅₀ ages are in good agreement with the quartz SAR-OSL ages， indicating the uncertainties of g-value correction. Based on the quartz SAR-OSL and K-feldspar pIRIR₁₅₀ ages， it is found that the geomorphological evolution at different sites in the study area show strong heterogeneity at local scales， while at glacial-interglacial time scales， their changes are broadly consistent with regional climatic changes. During the Last Glacial Maximum and Deglacial period， the dunes were mostly active and vegetation was degraded， and the areas of lakes and oases were relatively decreased. In contrast， dune activity was restricted and vegetation coverage was increased during the Early and Middle Holocene， and the lakes and oases were relatively expanded. During the past few hundreds of years， different sites in the Tengger Desert have probably undergone multiple phases of dune activation and stabilization， which may be related to not only regional environmental changes but also local disturbances.

The dry lake basin is one of the main sources of sandstorms in arid and semi-arid areas. With the burst of Zuo Lake in the source region of the Yangtze River， a large number of fragmentary materials from the lake bottom was exposed to the surface and became the new source of sand. The increasing sand storm disaster seriously threatened the ecological environment of Zuo Lake Basin and the safe operation of the Qinghai-Tibet Railway. In this paper， the grain size distribution and aeolian-sand flow structure of surface and aeolian-sand sediments after levee breach of Zuo Lake were obtained through systematic observation of aeolian-sand activities in three typical parts of west bank， south bank and east side of Zuo Lake. The results show that the west bank of Zuo Lake is the most intense area of sand activity in the basin， and the west bank and the south bank are the main source of sand and dust areas in the basin. The east side is the sedimentation area， and its blown sand sediments include both local sand materials and the dust from the west bank and the south bank. Due to the fine grain size of lacustrine sediments， the sand flow structure of west bank decreases linearly with height. Combined with the grain size results of surface and aeolian-sand flow sediments， it is speculated that the sand and dust initiation in Zuo Lake Basin is mainly aerodynamic entrainment， rather than the saltation bombardment as traditionally believed. The characteristics indicate that the aeolian sand activity in the dry lake basin in the plateau region is unique， and the prevention and control mode of low altitude areas cannot be copied in the prevention and control of aeolian-sand.

The soil erosion in China was characterized by various types and complicated processes. It is of great significance to accurately quantify the temporal variation and spatial patterns of soil wind erosion and water erosion intensity in watersheds， to identify regional dominant erosion types for reasonable arrangement of soil and water conservation measures. This study quantified the temporal and spatial patterns and evolution of soil wind erosion and water erosion intensity in the Yellow River Basin from 2000 to 2020 combined remote sensing monitoring， field survey， and model simulation， revealed soil erosion type area， and its significance to zoning control of soil erosion. The results showed that： （1） The intensity of soil wind erosion and water erosion in the region showed a downward trend as a whole， while the wind erosion and water erosion showed a fluctuation and continuous decrease， respectively. In the past 20 years， the modulus of soil wind erosion and soil water erosion have respectively decreased at a rate of 18.88 t·km^-2·a^-1 and 34.98 t·km^-2·a^-1. （2） The type zones dominated by soil wind erosion and soil water erosion accounted for 16.35% and 83.65% of the total land area of the region， respectively， and the overall performance of soil erosion type zoning from north to south was the transition from soil wind erosion to water erosion. The areas dominated by soil wind erosion were distributed in the upper reaches of the main stream of the Yellow River and the Ordos inland flow area， accounting for 41.53% and 28.57% of the area of soil wind erosion area， respectively. Moderate erosion intensity of soil wind erosion accounted for the largest proportion， 24.72%. The areas dominated by soil water erosion were distributed in the middle reaches of the Yellow River （25.04%）， the Wei River-Yiluo River system （22.06%）， the source water system of the Yellow River （18.60%）， the upper reaches of the Yellow River （15.49%）， Huangshui-Taohe River System （13.35%）. Soil water erosion was mainly micro-erosion intensity， accounting for 49.30% of the soil water erosion area， and light （17.28%）， moderate （14.98%） and strong erosion intensity （11.95%） were widely staggered. （3） Desertification control project and soil and water conservation engineering made soil erosion modulus and erosion intensity decrease significantly in areas with strong wind and water erosion. According to the zoning characteristics of soil erosion types， the measures of vegetation restoration and agricultural oases in the soil wind erosion area were discussed. Agricultural cultivation measures， forest and grass measures and engineering measures are used to protect and control soil water erosion areas， in order to provide scientific guidance for the high-quality development of the ecosystem in the Yellow River Basin.

This study focuses on wind-blown sand problems along highways， reviews the development history， current situation and characteristics of highways in sand region， and systematically summarizes wind-blown sand damage and achievements of sand control in China's sandy highways， according to wind-dynamical environments along highways， sand damage characteristics， disaster-causing mechanisms， wind-blown sand prevention and control measures along highway， structural composition and benefits of sand-control system. Considering that the drifting sands environments on both sides of the highway， gobi surface and the regional differences in natural environments， while taking into account the sand controlling， green corridor construction and landscape efficacy， and ensuring the continuous stability and functional perfection of road protection systems in sandy areas， three representative sand-control mode have been systematically sorted out to ensure the continued stability and functional perfection of the protection system for highways in sandy areas. Based on the practical needs of the increasing improvement of highway network skeleton system and the challenges of safe operation of highways in sandy areas， the focus is on strengthening the engineering and technical foundation of highway wind-blown sand control and improving the capacity of blown sand hazards control， and condensing and proposing the future research focus and development trend of sandy roads.

The dead Halogeton arachnoideus can still remain upright and play a role in sand fixation， making it a hotspot in the study of wind prevention and sand fixation in arid and semi-arid regions. On the basis of field investigation and grain size experiment， this paper analyzes the morphological and sedimentary characteristics of the shadow dunes of H. arachnoideus， a dead vegetation in the southern margin of Qaidam Basin， by using relevant statistical methods. The results show that： （1） The correlation between the parameters of shadow dune is significant （P<0.01）， in which the vertical and horizontal scales of dune have good correlation， and the fitting relationship between the length and width of dune （R²=0.6） is better than other parameters. （2） There is a significant positive correlation （0.8≥r>0.5， except dredge degree） between the parameters of dead H. arachnoideus and the shape of shadow dune. The contribution of vegetation length and width to the extension of dune length is gradually decreasing， while the contribution of vegetation height to it is increasing. （3） The canopy area， length and dredging degree of H. arachnoideus were significantly correlated with the volume of shadow dunes （P<0.01）， and the fitting relationship between canopy area and volume was good （R²=0.8）， which jointly affected the sand interception capacity of H. arachnoideus. （4） The main grain size fractions of the sediment are very fine sand and fine sand， Under the influence of plants， the wind force gradually decreases， and the grain size of sediment along the wind direction gradually becomes thicker.

Poyang Lake is the largest freshwater lake in China. At present， there are several sand hills around Poyang Lake， such as sand hills from Hukou county to Pengze county as well as Songmen Island in Wucheng Town. Previous studies suggest that these sand hills were formed by aeolian process， especially for the middle-top part of the sand hills. However， by field investigation， it was found that several sand/silt layers in the middle-top part of sand hills around Poyang Lake exhibit clear water-lain sedimentary structures. It is interesting that the elevation of these sand/silt layers was significantly higher than the highest water level of Poyang Lake since 1949. In this study， two representative sand layers with parallel bedding were targeted and two bulk samples were collected for particle size analysis. One sand sample （XZ-1） is collected from a sand layer with the parallel bedding within Shaling （sand hill） in Lushan city. Currently， the Wusong elevation of sand sample （XZ-1） is ~36.5 m. The other sand sample （HGDS-7） is collected from another sand layer with parallel bedding within a sand hill at Shazhou village in Hukou county. Currently， the Wusong elevation of sand sample （HGDS-7） is ~40.3 m. The results are as following： （1） Sand sample XZ-1 is moderately sorted， while sand sample HGDS-7 is poorly sorted. （2） The frequency curve of XZ-1 exhibits one main peak and a small peak， while that of HGDS-7 exhibits bimodal characteristics. （3） The log-probability accumulative curve of XZ-1 can be fitted by six distinctive populations， while the log-probability accumulative curve of HGDS-7 can be fitted by eight distinctive populations. （4） If the Sahu discriminant function is applied， Y value of XZ-1 is calculated at 3.71， while Y value of HGDS-7 is calculated at 8.89. The above particle size results are consistent with the interpretations by sedimentary structure， i.e. the targeted sand layers within the sand hills should be interpreted as water-lain sediments， rather than aeolian sediments， even though the targeted sand layers are much higher than the highest water level of Poyang Lake since 1949. In the future， more research should be carried out at different sand hills around Poyang Lake， to further understand the formation of the sand hills. It not only helps us better understand the evolution of Poyang Lake， but also be very useful for government policy on sustainable water supply， flood control and ecological safety on Poyang Lake.

As the water source of the Yellow River， the upper Yellow River basin is an important ecological function area in China. Analysis of ecological environmental quality changes in the upper Yellow River basin is important for ecological protection and high-quality economic development of the Yellow River basin. Based on Google Earth Engine platform， this paper analyzes the change of ecological environment quality in the upper Yellow River basin from 2000 to 2021 through remote sensing ecological index （RSEI）. The results show that： （1）The RSEI of the upper Yellow River basin is elevated. At the same time， it has the characteristics of stages. 2000-2005 is the stage of deterioration of ecological environment quality， and 2006-2021 is the stage of improvement of ecological environment quality. It is poor and moderate， accounting for 64.78% of the total area of the region. （2）The ecological quality of different river sections is different significantly， with the best ecological quality in the river source section and the worst ecological quality in the alluvial plain section. （3）The spatial clustering characteristics of ecological environment quality in the upper Yellow River basin are obvious， where high-high clustering areas are stably distributed near the river source section and low-low clustering areas are distributed in the canyon section and alluvial plain section where the intensity of human activities is higher. （4）Greenness， humidity， heat and dryness all have significant effects on the ecological quality of the upper Yellow River basin， with greenness as the dominant driver and dryness as the secondary driver. The increase of vegetation cover， climate regulation and soil and water conservation have significantly contributed to the ecological improvement of the upper Yellow River basin.

The Second National Conference on Combating Desert had been held in September， 1959 in Urumqi， which further to demonstrate the attention and expectation from the state's responsibility for prevention and control of aeolian desertification. In the years that followed， the Scientific Investigation Team for Combating Deserts， CAS and relevant provincial （autonomous region） departments carried out a more systematic investigation， experiment， research and practice. This paper focus on following three parts： （1） Based on the experimental investigations in the filed fixed station and semi-fixed station to comprehensive control of the desert， the author discusses some progress and function in the selection and introduction of plant species for moving dune fixing and optimal allocation， the mechanical sand fixation， the moving dune's moisture state and its stabilization and afforestation， the transpiration intensity of the major psammophytes， the process of soil formation in the fixed quicksand area and the dune soil microorganisms， etc. （2） Based on the research results of several major scientific and technological issues in prevention and control of aeolian desertification， the author discusses some main progress and function in the cause of the desert， the relationship between moving regular pattern of sand dune and wind prevention and sand-fixation， the assessment of aircraft seeding， the vegetation types and their evolution law in desert， the psammophytes characteristics， rational use of grassland in desert， the classification of the Gobi Desert and its transformation and utilization， water resources and their utilization， etc. （3） The author expounds briefly the process and the achievements of prevention and control of aeolian desertification during the establishment of the People's Republic of China （PRC） from 1949 to 1965，which affirmed the research objectives， formed the spirit of pioneering dedication and effective research method， and formed preliminarily in theory， practice， team and platform of the desert science. Thus laid the foundation and conditions for the start-up and pioneering of China Desert Science， so that let it enter the development period smoothly.

The arid and semi-arid areas in China are the important agricultural development regions. There are serious wind-erosion and dust emission in these regions， which threaten the sustainable development of agriculture and the balance of ecosystem. At present， dust emission schemes in weather and climate models only consider wind erosion over desert， and those occurred in farmland are seriously ignored or underestimated. It leads to large uncertainty for estimating dust physical processes and its climate impacts. This review summarizes scientific findings that have been published regarding the characteristics and parameterization of wind erosion in arid and semi-arid areas of China since the 1950s. The research progress and existing problems of wind erosion observation and numerical simulation in arid and semi-arid areas of China are discussed. It is of great significance for preventing and controlling wind-erosion， land desertification and understanding the impact of land use change on air pollution in arid and semi-arid areas of China in future.

The 10 years period of “Culture Revolution” from 1966 to 1976 had hindered the practice on prevention and control of aeolian desertification and the development of desert science to a certain degree. Nonetheless， relied on the foundation laid over the past decade， the science， technology and engineering teams from all levels of national to provincial and local carried on with scientific research， technological development and engineering implementation， field long-term observations and experiments， laboratory sample analysis and data statistics， blowing sand wind tunnel experiment， summary of results and writing of papers and monographs， etc. These efforts had obtained a batch of achievements， in which some of typical progress can be expressed as follows. （1） The construction and application of blowing sand wind tunnel created the pioneering work of wind tunnel experiment for prevention and control of aeolian desertification and research on law of wind-blown sand movement in China. （2） Some new results have been made in process and prevention of wind-sand disaster to the desert railway by systematically conducted on engineering technology experiments and theoretical research. （3） The work exchange meeting on desert control research of Chinese Academy of Sciences had successfully held in Lanzhou in March of 1975， which timely concluded and presented the theoretical and practical achievements and levels. （4） Systematically summarized the results of scientific investigations， observations， experiments， research， and practice， so that many scientific papers have been published as well as a series of monographs compiled and edited. There were some encouraged results of exploration and innovation on the distribution and general characteristics of deserts， causes of desert formation， source of sand material rising right on the spot， feature of wind-blown sand movement， formation and evolution mechanism of sand dunes in China and the development of aeolian geomorphology， morphological characteristics and movement patterns of sand dunes， regionalization of aeolian geomorphology and several landform issues for preventing blown sand disaster in the Taklamakan Desert. Other system summary results also delivered such as the management of farmland wind-blown sand disaster， railway's prevention and control of wind-blown sand damage， desert railway engineering construction as well as the successful experiences and effective measures from the Xinjiang， Gansu and Inner Mongolia Autonomous Region. All of the achievements and progress promoted the theoretical exploration and systematic composition of desert science in China.

Based on the month-by-month precipitation and runoff data from 12 hydrological stations and 35 rainfall stations in the main stream and eight tributaries of the Shiyang River Basin， wavelet analysis and double accumulation curve were used to study the change characteristics of runoff in the Shiyang River Basin. The results showed that： （1） The overall trend of runoff in the Shiyang River Basin was decreasing， with an average decrease of 0.37 billion m³ per 10 a.The runoff in the main stream of Shiyang River， Jinta River， Zamu River， Huangyang River and Gulang River decreased， and the runoff in the Xida River， Dongda River， Xiying River and Dajing River increased. （2） Nine hydrological stations in the Shiyang River Basin have periodic variations on time scales of 2-10 a and 10-30 a， among which the Zamusi station and the Huangyanghe reservoir station also have long periodic variations of 30-60 a， and the nine hydrological stations have the most obvious changes in abundance and depletion on time scales of 24， 21， 21， 21， 43， 45， 22， 17， 21 a， respectively. （3） The abrupt changes in the Shiyang River main stream and eight major tributaries occurred in 1971， 2014， 2000， 2018， 1960， 1959， 1962， 1994 and 1965， respectively， in which the runoff decreased after abrupt changes in the Shiyang River main stream， Jinta River， Zamu River， Huangyang River and Gulang River， increased after abrupt changes in the Xida River， Xiyang River and Dajing River， and did not have abrupt changes in the Dongda River. The results of the study can provide reference for the scientific management and optimal allocation of water resources in the Shiyang River basin and the implementation of subsequent ecological projects.

Horqin Sandy Land is one of the four sandy lands in China. It is also an important part of the sandstorm source in Beijing-Tianjin-Hebei. The intensification of desertification directly affects the climate environment in Beijing-Tianjin-Hebei. Based on the MEDALUS model， remote sensing and geographic information system technology are used to evaluate the desertification risk of Horqin Sandy Land. The desertification sensitivity index map of Horqin Sandy Land was constructed using soil quality， vegetation quality， climate quality and management quality indices. The results showed that the area with extremely high desertification sensitivity in Horqin Sandy Land was about 2 986.60 km²， accounting for 2.02% of the total area of the study area. The area with high desertification sensitivity was about 6 678.00 km²， accounting for 4.52%； The middle area was about 89 633.18 km²， accounting for 60.71%； The low area was about 48 352.20 km²， accounting for 32.75%. The result showed： （1） MEDALUS model is applicable in the evaluation of desertification sensitivity of Horqin Sandy Land. The assessed areas with extremely high desertification sensitivity index are concentrated in the hinterland of Horqin Sandy Land， both sides of Laoha River， the central and eastern part of Wengniute Banner， northwest of Naiman Banner and the middle part of Kulun Banner. （2） The influence of soil quality index on desertification sensitivity is higher than that of vegetation quality index， climate quality index， and management quality index. Therefore， improving the soil quality is likely to be an effect way to reduce the risk of land desertification in Horqin Sandy Land. （3） With the land use type as the main driving force， the desertification risk has increased in Tongliao City， northwest of Changling County， Horqin Left-wing Middle Banner， Shuangliao city and northern Zhangwu County. In addition， slope has little effect on desertification sensitivity in Horqin Sandy Land.

The problem of land desertification in northwest region of China is serious and the ecological environment is severe. It is of great significance to clarify the spatio-temporal variation characteristics and driving factors of vegetation cover in this area for ecological environment protection. In this study， MOD13A3 products in this area were used as the data source to obtain the NDVI sequence set from 2000 to 2019 through the maximum value synthesis method. Trend analysis， anomaly analysis， Hurst index， geographic detector， correlation analysis and residue analysis were used to analyze the spatiotemporal variation characteristics and impact factors of vegetation cover in the study area. The results showed that ：（1） In recent 20 years， the vegetation coverage in the study area showed an overall growth trend， with an increase rate of 0.0027·a^-1 and an average NDVI of 0.252. However， the growth rate of the Yellow River basin area （0.0062·a^-1） is higher than that of the semi-arid grassland area （0.0026·a^-1） and inland arid area （0.0018·a^-1）. （2） The vegetation coverage in the study area is on the rise， accounting for 55.77% of the total area， while the degraded area accounts for 3.76% of the total area. The increased land use types were mainly tillage， forest and grassland. The area with sustainable change trend of vegetation cover accounted for 31.87% of the total area， the sustainable improvement （17.04%） was greater than the sustainable degradation （1.27%）， and the growth and sustainable growth of the Yellow River basin area were the best. （3） The main contributing factors that affect the spatial distribution of vegetation cover are precipitation， temperature， sunshine and relative humidity in order of influence， but the influence degree of each sub-region is slightly different. The spatial distribution of arid areas in the Yellow River basin and inland is most affected by precipitation， and the semi-arid grassland is most affected by sunshine. （4） Vegetation cover changes is mainly driven by natural factors and human activities， and natural factors on the growth of vegetation role in promoting are greater than human activity， and natural factors on vegetation cover change in the rate of contribution are higher. The results of this study can provide reference for assessing the ecological environment change under the background of climate change in northwest China.

The Yellow River Basin bears an important ecological， economic and cultural strategic position in China， and its ecological environment is a vital foundation for ensuring the high-quality development of the Yellow River Basin. In this study， the long-term sequence of Remote Sensing Ecological Index （RSEI） of the Yellow River Basin was used to dynamically monitor and analyze the ecological quality changes in the Yellow River Basin in the past 20 years. The RSEI mean value is 0.497 from 2001 to 2019， increasing 0.04， which shows a trend of overall improvement and slight fluctuations. Moreover， its influencing factors were analyzed from three aspects： natural factors， policy measures and socio-economic factors. The complex natural factors bring difficulties to the governance of the Yellow River Basin， and the socio-economic factors such as continuously increasing population and night light data correspondingly disturbed the ecological environment changes， while the ecological protection policies and restoration measures play a positive role.

Soil carbon and nitrogen storage are of great significance to carbon and nitrogen cycles and global change researches. We use correlation analysis， random forest and SHAP interpretation methods to elucidate the distribution and variation patterns of soil surface carbon and nitrogen storages and determine the key influencing factors in the Urat National Nature Reserve of Haloxylon ammodendron. In this study， 61 plots were set up in the protection zone using the grid layout method， and the surface soil （0-20 cm） was collected to determine the soil carbon and nitrogen storage and analyze their main influencing factors. The carbon storage in the core area （1 429.91 g·m^-2） was significantly higher than those in the buffer area （1 194.09 g·m^-2） and the experimental area （986.36 g·m^-2）. The soil nitrogen storage in different areas did not differ significantly （P>0.05）， with 76.79 g·m^-2， 62.39 g·m^-2 and 51.28 g·m^-2 in the core， buffer and experimental area， respectively. Soil pH， electrical conductivity， the height of H. ammodendron， species richness， vegetation cover and herbaceous biomass differed significantly （P<0.05） among the three areas based on ANOVA. The key factors affecting soil carbon storage were soil carbon content， soil nitrogen content， soil water content， electrical conductivity， soil bulk density， the height of H. ammodendron， plant density and pH. SHAP analysis showed that soil bulk density and pH were negatively correlated with soil carbon storage， while the other significant factors were positively correlated with soil carbon storage. The key factors affecting soil nitrogen storage were soil nitrogen content， soil carbon content， electrical conductivity， soil bulk density， soil water content， the height of H. ammodendron， vegetation cover， C/N and plant density， and SHAP analysis showed that soil bulk density and C/N were negatively correlated with soil nitrogen storage， while the other significant factors were positively correlated with soil nitrogen storage. It was also found that the contribution to soil carbon and nitrogen storage was significantly increased for the average plant height of H. ammodendron higher than 2 m. Therefore， the sustainable management of H. ammodendron is beneficial on soil quality improvement in the Urat National Nature Reserve of H. ammodendron forest.

The coasts are the critical zones in which complex interactions among the land， ocean and atmosphere are intensive. The coastal aeolian deposits are a product in the dynamic environments， and therefore are good archives for studying evolution of coastal environments and changes in sea level. There are mainly three types of aeolian deposits along the coasts of China， i.e.， the “Old Red Sand”， aeolianites and sand dunes. This paper reviews the sedimentary characteristics of aeolian deposits by comparing the material composition and stratigraphic variability of different types of aeolian deposits that have been reported formerly. In this study， we selected the aeolian deposits sections dated by absolutely dating， used probability density function to analyze the distribution characteristics of the ages of aeolian deposits， investigated the history of aeolian activity on various timescales， and discussed key factors affecting coastal aeolian deposition along the coasts of China. The results show that aeolian activity on a glacial-interglacial scale were mainly recorded by the “Old Red Sand”. At around 120 ka BP and 73-55 ka BP， aeolian activity was mainly related to abundant sediment supply， originated from continental shelfs due to decline in sea level and strong winter monsoon circulation； whereas at around 105 ka BP and 80 ka BP， aeolian activity was ascribed to abundant sediment supply due to intensified runoffs resulted from enhanced monsoonal circulation and/or enhanced seasonality of monsoon climate. The decrease in the intensity of aeolian activity since 55 ka BP most likely reflected changes in preservation environments of sedimentation record， and most coastal aeolian deposits during the last glacial were inundated below the modern sea level， which does not mean that actual coastal aeolian activity weakened at that time. Aeolian activity recorded by sand dune deposits mainly occurred in the past 3 000 years， which may be related to the strengthened winter monsoon during the late Holocene. Our results may have been helpful for further understanding of key processes affecting coastal aeolian depositions and environmental changes as inferred from them.

Vegetation is an important component of terrestrial ecosystems， and it plays an important role in preventing desertification and conserving soil and water in arid and semi-arid regions. Fractional vegetation coverage （FVC）， in turn， is an important indicator of vegetation and ecological environment status. To understand the ecological status from 2000 to 2020 in Fenhe River Basin， this study examined the spatial distribution and temporal variations of vegetation coverage， investigated the vegetation response to ecological protection project. Our results demonstrate that： （1） The FVC increase from 55% in 2000 to 72% in 2020， with an increase rate of 0.87% per year， which is manifested with the increase of the high FVC area （FVC>60%）. The ecological environment quality of the region has been significantly improved. （2） Under the influence of ecological protection project， FVC increase in 77.1% of the area， and decrease in 1.7% of the area under the urbanization and mineral resources development. （3） The spatial and temporal variability of FVC are great， and the coefficient variation fluctuates between 0.01 and 2.20. The FVC is stable in original alpine forest area， valley agricultural area and urban construction. This study would provide a theoretical basis for formulating polices related to ecological environmental protection and sustainable development.

Impacting splash of saltating particles is the main dynamic mechanism of dust emission from gobi. However， due to the lack of high frequency measuring instruments and experimental methods， previous studies on gobi dust emission including wind tunnel experiments and field observation can not accurately and quantitatively study the impact of the energy of saltatingsand on the dust emission from gobi. In this study， the field wind tunnel experiments method was used to study the dynamic mechanism of the dust variation law in the near surface （0-20 cm） of the gobi and the dynamic mechanism of dust emission， and the different energy processes of saltating sand were measured by Sensit sensor. The results show that bombardment of saltating sands is one of the main factors of dust emission near surface of gobi and an important factor to assess the dust emission. Rebounding energy has the best correction with dust emission flux， followed by surface impact energy， and impact energy at 5cm above the ground has the weakest correction. It shows that the saltating sand bombardment and the conversion of impact energy and rebounding energy is an important dynamic process of dust emission.