The studied agriculture\|pasture interlacing zone has its specific natural conditions, at which the natural systems are unstable, their self\|regulation capability is low and the equilibrium is easily broken, and henc...The studied agriculture\|pasture interlacing zone has its specific natural conditions, at which the natural systems are unstable, their self\|regulation capability is low and the equilibrium is easily broken, and hence the habitat is fairly vulnerable. During last 20 years the increasing population and livestock, over\|reclamation, over\|pasturing, over\|deforesting, and other intensified negative human activities in the zone resulted in coarsening of surface soil, decrease of organic mater content in soil, reduction of vegetation coverage, variation and degradation of flora structure, and hence in desertization of the land, although average of gales and sandstorms some decreased and the climate tended to be better in the region. However, the frequent sandstorms occurring in the springs of last and present years has attracted much attention. Investigations confirmed that the main cause for the phenomena is the unreasonable human activities rather than the natural factors.展开更多
Based on study of China’s shelf glerenvironmnt, thes paper summarises the defini-tion of shelf desertization that occurred in the last stage of be Pleistocene, and discusses the backgroundof its formation and evoluti...Based on study of China’s shelf glerenvironmnt, thes paper summarises the defini-tion of shelf desertization that occurred in the last stage of be Pleistocene, and discusses the backgroundof its formation and evolution process. Study of shallow layer profiler records and core data revealed thatcold-dry aeolian erosion was the major exogenic force on the exposed shelf. Under the prevailing paleo-winter monsoon, part of the exposed drine straum disintegzated into sand and then desertizaion oc-curred. The fine sediments were blown away and deposited on the leeward to form derivative loess de-posits.展开更多
In the later stage of Late Pleistocene, global climate entered into the climax period of Wurm when temperature decreased remarkably and glaciers developed. Information from the East China Sea also confirm that the sea...In the later stage of Late Pleistocene, global climate entered into the climax period of Wurm when temperature decreased remarkably and glaciers developed. Information from the East China Sea also confirm that the sea level fell by at least 130 m at that time (Emery, 1968). The Bohai Sea and Yellow Sea at the climax period were totally exposed, while the East China Sea and South China Sea shelf regions were exposed partly. The exposed shelf area exceeded 1 million km2 and became a salty desert where land plants could not survive. Such were the conditions which led to the desertization of the shelf region.Eolation was the major exogenetic force not only on land but also on the shelf region in the ice age. At the climax period of Wiirm, the northern part of China developed thick layers of loess deposits. The shelf region at that time had similar climatic conditions and sediments. Because the shelf region was not protected by vegetation in the ice age, intensive wind storms remoulded the primarily展开更多
Based on the study of palaeo-environmental evolution in the shelves of the Eastern China Seas, the concept of "shelf desertization" in the late stage of Upper Pleistocene is defined; the environmental backgr...Based on the study of palaeo-environmental evolution in the shelves of the Eastern China Seas, the concept of "shelf desertization" in the late stage of Upper Pleistocene is defined; the environmental background and evolutionary process of shelf desertization are analysed. Study on the records of subbottom profiling and the data of core samples from shelf areas revealed that during low sea-level stages, the sedimentary environment in the exposed shelf plains was dominated by aeolian depositional process under cold and dry climatic conditions, i.e. under the action of strong winter-monsoon winds. Parts of the exposed marine strata were disintegrated, and aeolian sand dunes were formed on the disintegrated marine deposits, from which the finer sediment grains were blown away by wind and deposited in the downwind areas to form the derivative loess deposits. Thus a desertization environmental system was formed in the exposed shelf plains of the Eastern China Seas.展开更多
Badain Jaran Desert The Badain Jaran Desert,located in the north of Alxa Right Banner in Inner Mongolia and bordering Gansu Province to the west,is China’s third-largest and the world’s fourth-largest desert.Spannin...Badain Jaran Desert The Badain Jaran Desert,located in the north of Alxa Right Banner in Inner Mongolia and bordering Gansu Province to the west,is China’s third-largest and the world’s fourth-largest desert.Spanning an area of approximately 49,200 square km,with average altitudes ranging from 1,200 to 1,700 metres,this vast and majestic desert remains largely untouched,with around 10,000 square km still unexplored by humans.展开更多
The Taklimakan Desert,located in the heart of central Asia,covers approximately 330000 km^(2),making it China's largest desert and the world's second-largest shifting desert(Dong et al.,2024).With an average a...The Taklimakan Desert,located in the heart of central Asia,covers approximately 330000 km^(2),making it China's largest desert and the world's second-largest shifting desert(Dong et al.,2024).With an average annual precipitation of less than 100 mm and evaporation rates ranging from 2000 to 3000 mm(Yang et al.,2020),it is recognized as one of the driest regions on Earth,often referred to as the“sea of death”.展开更多
1 When Guo Chengwang started to plant the trees in the Mu Us Desert in northwest China's Shaanxi Province almost 40 years ago,he did not expect his efforts to fight against desertification to last.While just one o...1 When Guo Chengwang started to plant the trees in the Mu Us Desert in northwest China's Shaanxi Province almost 40 years ago,he did not expect his efforts to fight against desertification to last.While just one of the 2,000 saplings that he had planted in 1985 survived,he was still more than exalted to find that poplars(杨树)could grow in the desert.展开更多
On February 20,2025,China National Petroleum Corporation announced that China's first ultra-deep scientific exploration well-Shenditake 1 Well-successfully reached a depth of 10910 m underground(Fig.1).Deep Earth ...On February 20,2025,China National Petroleum Corporation announced that China's first ultra-deep scientific exploration well-Shenditake 1 Well-successfully reached a depth of 10910 m underground(Fig.1).Deep Earth Towerke 1 Well is located in the heart of the Taklamakan Desert in the Xinjiang Uyghur Autonomous Region,within the territory of Shaya County.It has become the deepest vertical well in Asia and the second deepest in the world.The well has successively set five major engineering records:The deepest global tailpipe cementing,the deepest global cable imaging logging,the fastest global onshore drilling to exceed 10000 m,the deepest direct well drilling in Asia,and the deepest onshore coring in Asia.This marks another major breakthrough for China in the field of“Deep Earth”exploration,following its achievements in“Deep Space”and“Deep Sea.”展开更多
Dunhuang,located in the northwestern part of China,is a town that feels like it's carved out of the pages of a history book.Nestled at the edge of the Gobi Desert in China's Gansu Province,this ancient oasis c...Dunhuang,located in the northwestern part of China,is a town that feels like it's carved out of the pages of a history book.Nestled at the edge of the Gobi Desert in China's Gansu Province,this ancient oasis city has been a crossroads of cultures,religions,and trade for over 2,000 years.展开更多
Climate change and human activities have led to desertification and decreased land productivity,significantly affecting human livelihoods in desert regions.Identifying suitable areas for cultivating economic and nativ...Climate change and human activities have led to desertification and decreased land productivity,significantly affecting human livelihoods in desert regions.Identifying suitable areas for cultivating economic and native plants based on ecological capacity,biological restoration,and risk management can be valuable tools for combating desertification.In this study,we identified suitable areas for the growth of economic and medicinal Moringa peregrina trees in desert regions of Sistan and Baluchestan Province,southern Iran,using library research and field methods.We also assessed the economic involvement of local communities in areas under different topographic conditions(namely flat area,undulating area,rolling area,moderately sloping area,and steep area)in the study area.Financial indicators such as the net present value(NPV),benefit-cost ratio(BCR),internal rate of return(IRR),and return on investment(ROI)were calculated for areas under various topographic conditions in the study area.The rolling area with results of NPV(6142.75 USD),IRR(103.38),BCR(5.38),and ROI(in the 3rd year)was the best region for investing and cultivating M.peregrina.The minimum economic level varied from 0.80 hm2 in the flat area to 21.60 hm2 in the steep area.Also,approximately 5,314,629.51 hm2 of desert lands in the study area were deemed suitable for M.peregrina cultivation,benefiting around 1,743,246 households in the study area.Cultivating M.peregrina in southern Iran can positively affect local communities and help preserve land from erosion.Our study will provide theoretical support for planting native species in other degraded desert regions to enhance ecosystem services and the well-being of indigenous populations.展开更多
Biological soil crusts(BSCs)play crucial roles in improving soil fertility and promoting plants settlement and reproduction in arid areas.However,the specific effects of BSCs on growth status and nutrient accumulation...Biological soil crusts(BSCs)play crucial roles in improving soil fertility and promoting plants settlement and reproduction in arid areas.However,the specific effects of BSCs on growth status and nutrient accumulation of plants are still unclear in different arid areas.This study analyzed the effects of three different BSCs treatments(without crust(WC),intact crust(IC),and broken crust(BC))on the growth,inorganic nutrient absorption,and organic solute synthesis of three typical desert plants(Grubovia dasyphylla(Fisch.&C.A.Mey.)Freitag&G.Kadereit,Nitraria tangutorum Bobrov,and Caragana koraiensis Kom.)in the Minqin desert-oasis ecotone of Northwest China.Results showed that the effects of three BSCs treatments on seed emergence and survival of three plants varied with seed types.The IC treatment significantly hindered the emergence and survival of seeds,while the BC treatment was more conducive to seed emergence and survival of plants.BSCs significantly promoted the growth of three plants,but their effects on plant growth varied at different stages of the growth.Briefly,the growth of G.dasyphylla was affected by BSCs in early stage,but the effects on the growth of G.dasyphylla significantly weakened in the middle and late stages.However,the growth of N.tangutorum and C.koraiensis only showed differences at the middle and late stages,with a significant enhancement in growth.Analysis of variance showed that BSCs,plant species,growth period,and their interactions had significant effects on the biomass and root:shoot ratio of three plants.BSC significantly affected the nutrients absorption and organic solute synthesis in plants.Specifically,BSCs significantly promoted nitrogen(N)absorption in plants and increased plant adaptability in N poor desert ecosystems,but had no significant effects on phosphorus(P)absorption.The effects of BSCs on inorganic nutrient absorption and organic solute synthesis in plants varied significantly among different plant species.The results suggest that BSCs have significant effects on the growth and nutrient accumulation of desert plants,which will provide theoretical basis for exploring the effects of BSCs on desert plant diversity,biodiversity conservation,and ecosystem management measures in arid and semi-arid areas.展开更多
CHINA Tarim Populus Euphratica National Nature Reserve Located along the northern edge of the Taklimakan Desert in Xinjiang,the Tarim Populus Euphratica National Nature Reserve lies in the middle reaches of the Tarim ...CHINA Tarim Populus Euphratica National Nature Reserve Located along the northern edge of the Taklimakan Desert in Xinjiang,the Tarim Populus Euphratica National Nature Reserve lies in the middle reaches of the Tarim River-the longest inland river in China-within Bayingolin Mongol Autonomous Prefecture.Established in 1983 and upgraded to a national reserve in 2006,it covers an area of about 395,420 hectares,including a core,bu!er,and experimental zone.The reserve features alluvial plains and desert terrain,with elevations ranging from 800 to 940 metres.The landscape consists of river floodplains,ancient riverbeds,and oasis margins,forming a remarkable ecological mosaic shaped by the Tarim River and its tributaries.The region experiences a typical temperate continental desert climate-dry,hot,and windy with scarce rainfall.展开更多
As the largest desert in China,the Taklimakan Desert features unique mobility and alternating mega-dune and inter-dune landscapes with rich dune types.Most areas of the sand sea were explored in the early 20th century...As the largest desert in China,the Taklimakan Desert features unique mobility and alternating mega-dune and inter-dune landscapes with rich dune types.Most areas of the sand sea were explored in the early 20th century.However,the eastern Taklimakan Desert characterized by extremely tall dunes,had received little attention until 2022 owing to transportation inconveniences.This study examined the alternating mega-dune and inter-dune landscapes in the eastern Taklimakan Desert,through spatial analysis and field surveys.Results demonstrate that the tallest mega-dunes are distributed primarily to the east of the central desert,with the occurrence of approximately 240 mega-dunes exceeding 150 m in height.The height-spacing relationship of mega-dunes with different orders exhibits a weak correlation,suggesting that the dune formation and evolution are more complex than previously documented;this could be attributed to the factors other than solely the wind regime.Additionally,from the field survey,we found that sand availability is the dominant factor for constraining the sustained growth of mega-dunes.A pattern coarsening may be responsible for the development of the dune fields in the eastern Taklimakan Desert,thus yielding constraints on the development of mega-dunes,and other dune fields on Earth as well.展开更多
Unstable environments intensify the frequency of extreme disasters.Long-term climate changes can lead to agricultural and ecological degradation that threatens population sustainability.To better understand past clima...Unstable environments intensify the frequency of extreme disasters.Long-term climate changes can lead to agricultural and ecological degradation that threatens population sustainability.To better understand past climatic events and consequences,here we present a reconstruction of the self-calibrating Palmer drought severity index(scPDSI)from September to August for the desert margins of northern China,dating back to 1742.The reconstruction accounts for 42.9%of the variation of meteorological data between 1951 and 2020.Our spatial correlation analyses showed significant correlations between scPDSI,runoff,and precipitation.Over the past 279 years,the study area has undergone nine dry and eight wet periods,with the most severe climate extremes between the 1850s and 1890s.This period of prolonged drought in northeastern China coincided with the combined impacts of climatic factors and human influences,contributing to the fall of the Qing Dynasty.Analysis of periodicity and anomalies in sea surface temperatures indicate a strong association between wet and dry cycles and El Niño-Southern Oscillations.Our findings offer insights into long-term dry and wet fluctuations at the desert margins in northern China and elucidate the relationship between drought and the dynamics of civilizations.They also highlight the potential impact of extremes in climate on modern society,especially under the four projected shared socioeconomic pathways climatic scenarios,which predict worsening droughts in northern China.展开更多
Desertification is a global crucial ecological and environmental issue,and China is among the countries most seriously affected by desertification.In recent decades,numerous independent studies on desertification dyna...Desertification is a global crucial ecological and environmental issue,and China is among the countries most seriously affected by desertification.In recent decades,numerous independent studies on desertification dynamics have been carried out using remote sensing technology,but there has been a lack of systematic research on desertification trends in China.This study employed the meta-analysis to integrate the findings of 140 published research cases and examined the dynamics of desertification in the eight major deserts,four major sandy lands,and their surrounding areas in China from 1970 to 2019,with a comparative analysis of differences between the eastern(including the Mu Us Sandy Land,the Otindag Sandy Land,the Hulunbuir Sandy Land,the Horqin Sandy Land,and the Hobq Desert)and western(including the Taklimakan Desert,the Gurbantunggut Desert,the Kumtagh Desert,the Ulan Buh Desert,the Qaidam Basin Desert,the Badain Jaran Desert,and the Tengger Desert)regions.The results revealed that from 1970 to 2019,desertification first expanded and then reversed in the whole region.Specifically,desertification expanded from 1980 to 1999 and reversed after 2000.The desertification trend exhibited distinct spatio-temporal variations between the eastern and western regions.From 1970 to 2019,the western region experienced relatively minor changes in desertified land area compared to the eastern region.In the context of global climate change,beneficial climatic conditions and ecological construction projects played a crucial role in reversing desertification.These findings provide valuable insights for understanding the development patterns of desertification in the most representative deserts and sandy lands in China and formulating effective desertification control strategies.展开更多
The microbiome of mammals has profound effects on host ftness,but the process,which drives the assembly and shift of mammalian microbiome remains poorly understood.To explore the patterns of small mammal microbial com...The microbiome of mammals has profound effects on host ftness,but the process,which drives the assembly and shift of mammalian microbiome remains poorly understood.To explore the patterns of small mammal microbial communities across host species and geographical sites and measure the relative contributions of different processes in driving assembly patterns,2 sympatric desert rodent species(Dipus sagitta and Meriones meridianus)were sampled from 2 geographically distant regions,which differed in the environment,followed by 16S rRNA gene sequencing.The microbiomes differed signifcantly between D.sagitta and M.meridianus,and linear mixed modeling(LMM)analysis revealed that microbial diversity was mostly affected by species rather than the environment.For each rodent species,the microbiome diversity and structure differed across geographical regions,with individuals from lower rainfall environments exhibiting greater diversity.The null modeling results suggested dispersal limitation and ecological drift rather than differential selective pressures acting on the microbiome.In addition,each group had a different core genus,suggesting that the taxonomic composition of the microbiome was shaped most strongly by stochastic processes.Our results suggest that variation in the microbiome between hosts,both within and among geographic rodent populations,is driven by bacterial dispersal and ecological drift rather than by differential selective pressures.These results elucidated the diversity patterns and assembly processes of bacterial microbiomes in small desert mammals.Deciphering the processes shaping the assembly of the microbial community is a premise for better understanding how the environment-host-microbe interactions of mammals are established and maintained,particularly in the context of increased environmental disturbances and global changes.展开更多
The Taklimakan Desert,China’s largest desert and the world’s second-largest shifting desert,is now fully encircled by a 3,046-km sand-blocking green belt.Located in northwest China,the desert spans 337,600 square km...The Taklimakan Desert,China’s largest desert and the world’s second-largest shifting desert,is now fully encircled by a 3,046-km sand-blocking green belt.Located in northwest China,the desert spans 337,600 square km.Encircling the desert with a green belt was a monumental undertaking,taking more than 40 years to complete.Alongside this project,sand-based industries,such as the cultivation of cistanche and other crops,have been developed to raise local incomes.展开更多
Climate change is expected to alter the frequency and intensity of drying-rewetting cycles,impacting water availability and consequently soil nutrient availability.However,the effects of these fluctuations on the chem...Climate change is expected to alter the frequency and intensity of drying-rewetting cycles,impacting water availability and consequently soil nutrient availability.However,the effects of these fluctuations on the chemical speciation and bioavailability of phosphorus(P)in soil remain uncertain,both in the presence of desert species and in their absence.We conducted a pot experiment involving bare soil(absence of plants)and two desert species(Alhagi sparsifolia and Calligonum mongolicum)to determine the short-term impacts of drought(no water supply),drying-rewetting 1(D-RW1,high frequency of low water inputs),and drying-rewetting 2(D-RW2,low frequency of high water inputs)on soil Hedley P pools,plant P concentration,and plant biomass accumulation.Results demonstrated that the presence of plants significantly increased soil labile P and organic P(Po)concentrations by 60%–150%and 1%–68%,respectively,compared to the absence of plants.Both D-RW1 and D-RW2 treatments significantly increased soil dissolved organic carbon concentration by 2%–35%relative to the drought treatment.Moreover,in the presence of A.sparsifolia,soil resin-extractable P and NaHCO_(3)-extractable inorganic P(Pi)concentrations in the D-RW1 treatment significantly increased by 31%and 75%,respectively,when compared to the drought treatment,with the NaHCO_(3)-and NaOH-extractable Po concentrations in the D-RW2 treatment rising by 14%and 32%,respectively.Furthermore,the D-RW2 treatment significantly increased leaf P concentration and plant biomass compared to the D-RW1 and drought treatments.Overall,compared to the drought treatment,frequent low-intensity drying-rewetting cycles enhanced soil Pi turnover,whereas infrequent high-intensity drying-rewetting cycles increased Po turnover and P bioavailability.These findings will inform better water management strategies for desertification restoration in hyper-arid desert ecosystems.展开更多
Empirical formulas are indispensable tools in water engineering and hydraulic structure design.Derived from meticulous field observations,experiments,and diverse datasets,these formulas help to estimate water leakage ...Empirical formulas are indispensable tools in water engineering and hydraulic structure design.Derived from meticulous field observations,experiments,and diverse datasets,these formulas help to estimate water leakage in structures such as dams,tunnels,canals,and pipelines.By utilizing a few easily measurable parameters,engineers can employ these formulas to generate preliminary leakage rate estimates before proceeding with more detailed analyses.In this study,a physical model was developed,and a series of experiments were conducted,considering variables such as inflow rate,materials constituting the unsaturated medium,and variations in infiltration trench depth and width.As a result,a novel artificial recharge method was introduced,and an empirical equation,Q_(out)=0.0066×D_(50)^(0.64)×L×P^(0.36),was proposed to estimate the infiltration capacity of the trench.This equation incorporates factors such as the wetted perimeter,mean soil particle diameter,trench length,and a coefficient.A comparative analysis between the observed data from nine Iranian earthen canals and the values calculated using the proposed equation revealed an average relative error of 15%between the two datasets.In addition,the Pearson correlation coefficient was determined to be 0.981 and the Root Mean Square Error(RMSE)was 0.381,demonstrating the strong predictive performance of the equation.The parameters considered in the proposed equation allow for its application across diverse regions.Given its accurate performance,this equation provides a reliable initial estimate of the leakage rate,thereby helping to reduce costs and save time.展开更多
Biomass is among the most important state variables used to characterize ecosystems. Estimation of tree biomass involves the development of species-specific “allometric equations” that describe the relationship betw...Biomass is among the most important state variables used to characterize ecosystems. Estimation of tree biomass involves the development of species-specific “allometric equations” that describe the relationship between tree biomass and tree diameter and/or height. While many allometric equations were developed for northern hemisphere and tropical species, rarely have they been developed for trees in arid ecosystems, limiting, amongst other things, our ability to estimate carbon stocks in arid regions. Acacia raddiana and A. tortilis are major components of savannas and arid regions in the Middle East and Africa, where they are considered keystone species. Using the opportunity that trees were being uprooted for land development, we measured height (H), north-south (C1) and east-west (C2) canopy diameters, stem diameter at 1.3 meters of the largest stem (D1.3 or DBH), and aboveground fresh and dry weight (FW and DW, respectively) of nine trees (n = 9) from each species. For A. tortilis only, we recorded the number of trunks, and measured the diameter of the largest trunk at ground level (D0). While the average crown (canopy) size (C1 + C2) was very similar among the two species, Acacia raddiana trees were found to be significantly taller than their Acacia tortilis counterparts. Results show that in the arid Arava (southern Israel), an average adult acacia tree has ~200 kg of aboveground dry biomass and that a typical healthy acacia ecosystem in this region, may include ~41 tons of tree biomass per km2. The coefficients of DBH (tree diameter at breast height) to biomass and wood volume, could be used by researchers studying acacia trees throughout the Middle East and Africa, enabling them to estimate biomass of acacia trees and to evaluate their importance for carbon stocks in their arid regions. Highlights: 1) Estimations of tree biomass in arid regions are rare. 2) Biomass allometric equations were developed for A. raddiana and A. tortilis trees. 3) Equations contribute to the estimation of carbon stocks in arid regions.展开更多
文摘The studied agriculture\|pasture interlacing zone has its specific natural conditions, at which the natural systems are unstable, their self\|regulation capability is low and the equilibrium is easily broken, and hence the habitat is fairly vulnerable. During last 20 years the increasing population and livestock, over\|reclamation, over\|pasturing, over\|deforesting, and other intensified negative human activities in the zone resulted in coarsening of surface soil, decrease of organic mater content in soil, reduction of vegetation coverage, variation and degradation of flora structure, and hence in desertization of the land, although average of gales and sandstorms some decreased and the climate tended to be better in the region. However, the frequent sandstorms occurring in the springs of last and present years has attracted much attention. Investigations confirmed that the main cause for the phenomena is the unreasonable human activities rather than the natural factors.
文摘Based on study of China’s shelf glerenvironmnt, thes paper summarises the defini-tion of shelf desertization that occurred in the last stage of be Pleistocene, and discusses the backgroundof its formation and evolution process. Study of shallow layer profiler records and core data revealed thatcold-dry aeolian erosion was the major exogenic force on the exposed shelf. Under the prevailing paleo-winter monsoon, part of the exposed drine straum disintegzated into sand and then desertizaion oc-curred. The fine sediments were blown away and deposited on the leeward to form derivative loess de-posits.
基金Project sponsored by the National Natural Science Foundation of China
文摘In the later stage of Late Pleistocene, global climate entered into the climax period of Wurm when temperature decreased remarkably and glaciers developed. Information from the East China Sea also confirm that the sea level fell by at least 130 m at that time (Emery, 1968). The Bohai Sea and Yellow Sea at the climax period were totally exposed, while the East China Sea and South China Sea shelf regions were exposed partly. The exposed shelf area exceeded 1 million km2 and became a salty desert where land plants could not survive. Such were the conditions which led to the desertization of the shelf region.Eolation was the major exogenetic force not only on land but also on the shelf region in the ice age. At the climax period of Wiirm, the northern part of China developed thick layers of loess deposits. The shelf region at that time had similar climatic conditions and sediments. Because the shelf region was not protected by vegetation in the ice age, intensive wind storms remoulded the primarily
文摘Based on the study of palaeo-environmental evolution in the shelves of the Eastern China Seas, the concept of "shelf desertization" in the late stage of Upper Pleistocene is defined; the environmental background and evolutionary process of shelf desertization are analysed. Study on the records of subbottom profiling and the data of core samples from shelf areas revealed that during low sea-level stages, the sedimentary environment in the exposed shelf plains was dominated by aeolian depositional process under cold and dry climatic conditions, i.e. under the action of strong winter-monsoon winds. Parts of the exposed marine strata were disintegrated, and aeolian sand dunes were formed on the disintegrated marine deposits, from which the finer sediment grains were blown away by wind and deposited in the downwind areas to form the derivative loess deposits. Thus a desertization environmental system was formed in the exposed shelf plains of the Eastern China Seas.
文摘Badain Jaran Desert The Badain Jaran Desert,located in the north of Alxa Right Banner in Inner Mongolia and bordering Gansu Province to the west,is China’s third-largest and the world’s fourth-largest desert.Spanning an area of approximately 49,200 square km,with average altitudes ranging from 1,200 to 1,700 metres,this vast and majestic desert remains largely untouched,with around 10,000 square km still unexplored by humans.
基金supported by the National Natural Science Foundation of China(No.42072211)the National Natural Science Foundation of China(No.42401048)the Third Xinjiang Scientific Expedition and Research Program(No.2021xjkk0302)。
文摘The Taklimakan Desert,located in the heart of central Asia,covers approximately 330000 km^(2),making it China's largest desert and the world's second-largest shifting desert(Dong et al.,2024).With an average annual precipitation of less than 100 mm and evaporation rates ranging from 2000 to 3000 mm(Yang et al.,2020),it is recognized as one of the driest regions on Earth,often referred to as the“sea of death”.
文摘1 When Guo Chengwang started to plant the trees in the Mu Us Desert in northwest China's Shaanxi Province almost 40 years ago,he did not expect his efforts to fight against desertification to last.While just one of the 2,000 saplings that he had planted in 1985 survived,he was still more than exalted to find that poplars(杨树)could grow in the desert.
文摘On February 20,2025,China National Petroleum Corporation announced that China's first ultra-deep scientific exploration well-Shenditake 1 Well-successfully reached a depth of 10910 m underground(Fig.1).Deep Earth Towerke 1 Well is located in the heart of the Taklamakan Desert in the Xinjiang Uyghur Autonomous Region,within the territory of Shaya County.It has become the deepest vertical well in Asia and the second deepest in the world.The well has successively set five major engineering records:The deepest global tailpipe cementing,the deepest global cable imaging logging,the fastest global onshore drilling to exceed 10000 m,the deepest direct well drilling in Asia,and the deepest onshore coring in Asia.This marks another major breakthrough for China in the field of“Deep Earth”exploration,following its achievements in“Deep Space”and“Deep Sea.”
文摘Dunhuang,located in the northwestern part of China,is a town that feels like it's carved out of the pages of a history book.Nestled at the edge of the Gobi Desert in China's Gansu Province,this ancient oasis city has been a crossroads of cultures,religions,and trade for over 2,000 years.
基金funded by the Chinese Academy of Sciences President's International Fellowship Initiative(2024VCC0009).
文摘Climate change and human activities have led to desertification and decreased land productivity,significantly affecting human livelihoods in desert regions.Identifying suitable areas for cultivating economic and native plants based on ecological capacity,biological restoration,and risk management can be valuable tools for combating desertification.In this study,we identified suitable areas for the growth of economic and medicinal Moringa peregrina trees in desert regions of Sistan and Baluchestan Province,southern Iran,using library research and field methods.We also assessed the economic involvement of local communities in areas under different topographic conditions(namely flat area,undulating area,rolling area,moderately sloping area,and steep area)in the study area.Financial indicators such as the net present value(NPV),benefit-cost ratio(BCR),internal rate of return(IRR),and return on investment(ROI)were calculated for areas under various topographic conditions in the study area.The rolling area with results of NPV(6142.75 USD),IRR(103.38),BCR(5.38),and ROI(in the 3rd year)was the best region for investing and cultivating M.peregrina.The minimum economic level varied from 0.80 hm2 in the flat area to 21.60 hm2 in the steep area.Also,approximately 5,314,629.51 hm2 of desert lands in the study area were deemed suitable for M.peregrina cultivation,benefiting around 1,743,246 households in the study area.Cultivating M.peregrina in southern Iran can positively affect local communities and help preserve land from erosion.Our study will provide theoretical support for planting native species in other degraded desert regions to enhance ecosystem services and the well-being of indigenous populations.
基金supported by the Natural Science Foundation of Gansu Province,China(24JRRA733,23JRRA589)the National Natural Science Foundation of China(42377470,42207539)the Light of Western Light Program of Talent Cultivation of Chinese Academy of Sciences(22JR9KA028).
文摘Biological soil crusts(BSCs)play crucial roles in improving soil fertility and promoting plants settlement and reproduction in arid areas.However,the specific effects of BSCs on growth status and nutrient accumulation of plants are still unclear in different arid areas.This study analyzed the effects of three different BSCs treatments(without crust(WC),intact crust(IC),and broken crust(BC))on the growth,inorganic nutrient absorption,and organic solute synthesis of three typical desert plants(Grubovia dasyphylla(Fisch.&C.A.Mey.)Freitag&G.Kadereit,Nitraria tangutorum Bobrov,and Caragana koraiensis Kom.)in the Minqin desert-oasis ecotone of Northwest China.Results showed that the effects of three BSCs treatments on seed emergence and survival of three plants varied with seed types.The IC treatment significantly hindered the emergence and survival of seeds,while the BC treatment was more conducive to seed emergence and survival of plants.BSCs significantly promoted the growth of three plants,but their effects on plant growth varied at different stages of the growth.Briefly,the growth of G.dasyphylla was affected by BSCs in early stage,but the effects on the growth of G.dasyphylla significantly weakened in the middle and late stages.However,the growth of N.tangutorum and C.koraiensis only showed differences at the middle and late stages,with a significant enhancement in growth.Analysis of variance showed that BSCs,plant species,growth period,and their interactions had significant effects on the biomass and root:shoot ratio of three plants.BSC significantly affected the nutrients absorption and organic solute synthesis in plants.Specifically,BSCs significantly promoted nitrogen(N)absorption in plants and increased plant adaptability in N poor desert ecosystems,but had no significant effects on phosphorus(P)absorption.The effects of BSCs on inorganic nutrient absorption and organic solute synthesis in plants varied significantly among different plant species.The results suggest that BSCs have significant effects on the growth and nutrient accumulation of desert plants,which will provide theoretical basis for exploring the effects of BSCs on desert plant diversity,biodiversity conservation,and ecosystem management measures in arid and semi-arid areas.
文摘CHINA Tarim Populus Euphratica National Nature Reserve Located along the northern edge of the Taklimakan Desert in Xinjiang,the Tarim Populus Euphratica National Nature Reserve lies in the middle reaches of the Tarim River-the longest inland river in China-within Bayingolin Mongol Autonomous Prefecture.Established in 1983 and upgraded to a national reserve in 2006,it covers an area of about 395,420 hectares,including a core,bu!er,and experimental zone.The reserve features alluvial plains and desert terrain,with elevations ranging from 800 to 940 metres.The landscape consists of river floodplains,ancient riverbeds,and oasis margins,forming a remarkable ecological mosaic shaped by the Tarim River and its tributaries.The region experiences a typical temperate continental desert climate-dry,hot,and windy with scarce rainfall.
基金The Third Xinjiang Scientific Expedition and Research Program:Investigation and Risk Assessment of Drought and Aeolian Disasters in Tarim River Basin,No.2021xjkk0300Xinjiang Tianshan Talent Program,No.2022TSYCLJ0002National Natural Science Foundation of China,No.42471013。
文摘As the largest desert in China,the Taklimakan Desert features unique mobility and alternating mega-dune and inter-dune landscapes with rich dune types.Most areas of the sand sea were explored in the early 20th century.However,the eastern Taklimakan Desert characterized by extremely tall dunes,had received little attention until 2022 owing to transportation inconveniences.This study examined the alternating mega-dune and inter-dune landscapes in the eastern Taklimakan Desert,through spatial analysis and field surveys.Results demonstrate that the tallest mega-dunes are distributed primarily to the east of the central desert,with the occurrence of approximately 240 mega-dunes exceeding 150 m in height.The height-spacing relationship of mega-dunes with different orders exhibits a weak correlation,suggesting that the dune formation and evolution are more complex than previously documented;this could be attributed to the factors other than solely the wind regime.Additionally,from the field survey,we found that sand availability is the dominant factor for constraining the sustained growth of mega-dunes.A pattern coarsening may be responsible for the development of the dune fields in the eastern Taklimakan Desert,thus yielding constraints on the development of mega-dunes,and other dune fields on Earth as well.
基金supported by the National Natural Science Foundation of China(32061123008).
文摘Unstable environments intensify the frequency of extreme disasters.Long-term climate changes can lead to agricultural and ecological degradation that threatens population sustainability.To better understand past climatic events and consequences,here we present a reconstruction of the self-calibrating Palmer drought severity index(scPDSI)from September to August for the desert margins of northern China,dating back to 1742.The reconstruction accounts for 42.9%of the variation of meteorological data between 1951 and 2020.Our spatial correlation analyses showed significant correlations between scPDSI,runoff,and precipitation.Over the past 279 years,the study area has undergone nine dry and eight wet periods,with the most severe climate extremes between the 1850s and 1890s.This period of prolonged drought in northeastern China coincided with the combined impacts of climatic factors and human influences,contributing to the fall of the Qing Dynasty.Analysis of periodicity and anomalies in sea surface temperatures indicate a strong association between wet and dry cycles and El Niño-Southern Oscillations.Our findings offer insights into long-term dry and wet fluctuations at the desert margins in northern China and elucidate the relationship between drought and the dynamics of civilizations.They also highlight the potential impact of extremes in climate on modern society,especially under the four projected shared socioeconomic pathways climatic scenarios,which predict worsening droughts in northern China.
基金supported by the State Key Research and Development Program of China(2023YFF1305304)the Open Bidding for Selecting the Best Candidates Project of Inner Mongolia Autonomous Region(2024JBGS0020).
文摘Desertification is a global crucial ecological and environmental issue,and China is among the countries most seriously affected by desertification.In recent decades,numerous independent studies on desertification dynamics have been carried out using remote sensing technology,but there has been a lack of systematic research on desertification trends in China.This study employed the meta-analysis to integrate the findings of 140 published research cases and examined the dynamics of desertification in the eight major deserts,four major sandy lands,and their surrounding areas in China from 1970 to 2019,with a comparative analysis of differences between the eastern(including the Mu Us Sandy Land,the Otindag Sandy Land,the Hulunbuir Sandy Land,the Horqin Sandy Land,and the Hobq Desert)and western(including the Taklimakan Desert,the Gurbantunggut Desert,the Kumtagh Desert,the Ulan Buh Desert,the Qaidam Basin Desert,the Badain Jaran Desert,and the Tengger Desert)regions.The results revealed that from 1970 to 2019,desertification first expanded and then reversed in the whole region.Specifically,desertification expanded from 1980 to 1999 and reversed after 2000.The desertification trend exhibited distinct spatio-temporal variations between the eastern and western regions.From 1970 to 2019,the western region experienced relatively minor changes in desertified land area compared to the eastern region.In the context of global climate change,beneficial climatic conditions and ecological construction projects played a crucial role in reversing desertification.These findings provide valuable insights for understanding the development patterns of desertification in the most representative deserts and sandy lands in China and formulating effective desertification control strategies.
基金supported by grants from the Third Xinjiang Scientifc Expedition Program(Grant No.2022xjkk0205 to Lin Xia,Grant No.2021xjkk0604 to Jilong Cheng)the Joint Fund of National Natural Science Foundation of China(Grant No.U2003203 to Lin Xia)+1 种基金the Western Young Scholar Program-B of the Chinese Academy of Sciences(Grant No.2021-XBQNXZ-014 to Muyang Wang)the National Natural Science Foundation of China(Grant No.32170416 to Qisen Yang and Grant No.32370472 to Jilong Cheng).
文摘The microbiome of mammals has profound effects on host ftness,but the process,which drives the assembly and shift of mammalian microbiome remains poorly understood.To explore the patterns of small mammal microbial communities across host species and geographical sites and measure the relative contributions of different processes in driving assembly patterns,2 sympatric desert rodent species(Dipus sagitta and Meriones meridianus)were sampled from 2 geographically distant regions,which differed in the environment,followed by 16S rRNA gene sequencing.The microbiomes differed signifcantly between D.sagitta and M.meridianus,and linear mixed modeling(LMM)analysis revealed that microbial diversity was mostly affected by species rather than the environment.For each rodent species,the microbiome diversity and structure differed across geographical regions,with individuals from lower rainfall environments exhibiting greater diversity.The null modeling results suggested dispersal limitation and ecological drift rather than differential selective pressures acting on the microbiome.In addition,each group had a different core genus,suggesting that the taxonomic composition of the microbiome was shaped most strongly by stochastic processes.Our results suggest that variation in the microbiome between hosts,both within and among geographic rodent populations,is driven by bacterial dispersal and ecological drift rather than by differential selective pressures.These results elucidated the diversity patterns and assembly processes of bacterial microbiomes in small desert mammals.Deciphering the processes shaping the assembly of the microbial community is a premise for better understanding how the environment-host-microbe interactions of mammals are established and maintained,particularly in the context of increased environmental disturbances and global changes.
文摘The Taklimakan Desert,China’s largest desert and the world’s second-largest shifting desert,is now fully encircled by a 3,046-km sand-blocking green belt.Located in northwest China,the desert spans 337,600 square km.Encircling the desert with a green belt was a monumental undertaking,taking more than 40 years to complete.Alongside this project,sand-based industries,such as the cultivation of cistanche and other crops,have been developed to raise local incomes.
基金supported by the National Natural Science Foundation of China (Nos. 42271071, 42207163,and 32250410301)the Postdoctoral Fellowship Program of China (No. GZC20232964)+5 种基金the “Tianchi Talents” Introduction Program, Xinjiang, China, the Ministry of Science and Technology, China (Nos. QN2022045005L and WGXZ2023078L)the National Key Research and Development Project of China (No. 2022YFF1302504)Josep PENUELAS and Jordi SARDANS were funded by the Spanish Government grants PID2020115770RB-I, TED2021132627 B-I00, and PID2022-140808NB-I00funded by the Ministry of Science and Innovation (MCIN) and the Agencia Espa?ola de Investigación (AEI), Spainsupported by the European Union’s Next Generation EU/PRTR program, the Fundación Ramón Areces grant CIVP20A6621Spain, and the Catalan Government grant SGR 2021–1333, Spain
文摘Climate change is expected to alter the frequency and intensity of drying-rewetting cycles,impacting water availability and consequently soil nutrient availability.However,the effects of these fluctuations on the chemical speciation and bioavailability of phosphorus(P)in soil remain uncertain,both in the presence of desert species and in their absence.We conducted a pot experiment involving bare soil(absence of plants)and two desert species(Alhagi sparsifolia and Calligonum mongolicum)to determine the short-term impacts of drought(no water supply),drying-rewetting 1(D-RW1,high frequency of low water inputs),and drying-rewetting 2(D-RW2,low frequency of high water inputs)on soil Hedley P pools,plant P concentration,and plant biomass accumulation.Results demonstrated that the presence of plants significantly increased soil labile P and organic P(Po)concentrations by 60%–150%and 1%–68%,respectively,compared to the absence of plants.Both D-RW1 and D-RW2 treatments significantly increased soil dissolved organic carbon concentration by 2%–35%relative to the drought treatment.Moreover,in the presence of A.sparsifolia,soil resin-extractable P and NaHCO_(3)-extractable inorganic P(Pi)concentrations in the D-RW1 treatment significantly increased by 31%and 75%,respectively,when compared to the drought treatment,with the NaHCO_(3)-and NaOH-extractable Po concentrations in the D-RW2 treatment rising by 14%and 32%,respectively.Furthermore,the D-RW2 treatment significantly increased leaf P concentration and plant biomass compared to the D-RW1 and drought treatments.Overall,compared to the drought treatment,frequent low-intensity drying-rewetting cycles enhanced soil Pi turnover,whereas infrequent high-intensity drying-rewetting cycles increased Po turnover and P bioavailability.These findings will inform better water management strategies for desertification restoration in hyper-arid desert ecosystems.
文摘Empirical formulas are indispensable tools in water engineering and hydraulic structure design.Derived from meticulous field observations,experiments,and diverse datasets,these formulas help to estimate water leakage in structures such as dams,tunnels,canals,and pipelines.By utilizing a few easily measurable parameters,engineers can employ these formulas to generate preliminary leakage rate estimates before proceeding with more detailed analyses.In this study,a physical model was developed,and a series of experiments were conducted,considering variables such as inflow rate,materials constituting the unsaturated medium,and variations in infiltration trench depth and width.As a result,a novel artificial recharge method was introduced,and an empirical equation,Q_(out)=0.0066×D_(50)^(0.64)×L×P^(0.36),was proposed to estimate the infiltration capacity of the trench.This equation incorporates factors such as the wetted perimeter,mean soil particle diameter,trench length,and a coefficient.A comparative analysis between the observed data from nine Iranian earthen canals and the values calculated using the proposed equation revealed an average relative error of 15%between the two datasets.In addition,the Pearson correlation coefficient was determined to be 0.981 and the Root Mean Square Error(RMSE)was 0.381,demonstrating the strong predictive performance of the equation.The parameters considered in the proposed equation allow for its application across diverse regions.Given its accurate performance,this equation provides a reliable initial estimate of the leakage rate,thereby helping to reduce costs and save time.
文摘Biomass is among the most important state variables used to characterize ecosystems. Estimation of tree biomass involves the development of species-specific “allometric equations” that describe the relationship between tree biomass and tree diameter and/or height. While many allometric equations were developed for northern hemisphere and tropical species, rarely have they been developed for trees in arid ecosystems, limiting, amongst other things, our ability to estimate carbon stocks in arid regions. Acacia raddiana and A. tortilis are major components of savannas and arid regions in the Middle East and Africa, where they are considered keystone species. Using the opportunity that trees were being uprooted for land development, we measured height (H), north-south (C1) and east-west (C2) canopy diameters, stem diameter at 1.3 meters of the largest stem (D1.3 or DBH), and aboveground fresh and dry weight (FW and DW, respectively) of nine trees (n = 9) from each species. For A. tortilis only, we recorded the number of trunks, and measured the diameter of the largest trunk at ground level (D0). While the average crown (canopy) size (C1 + C2) was very similar among the two species, Acacia raddiana trees were found to be significantly taller than their Acacia tortilis counterparts. Results show that in the arid Arava (southern Israel), an average adult acacia tree has ~200 kg of aboveground dry biomass and that a typical healthy acacia ecosystem in this region, may include ~41 tons of tree biomass per km2. The coefficients of DBH (tree diameter at breast height) to biomass and wood volume, could be used by researchers studying acacia trees throughout the Middle East and Africa, enabling them to estimate biomass of acacia trees and to evaluate their importance for carbon stocks in their arid regions. Highlights: 1) Estimations of tree biomass in arid regions are rare. 2) Biomass allometric equations were developed for A. raddiana and A. tortilis trees. 3) Equations contribute to the estimation of carbon stocks in arid regions.
