Central Asia revealed as a key area in evolution of Eremurus (Asphodelaceae)

Eremurus was described at the beginning of the 19th century.However,due to limited sampling and the small number of gene markers to date,its phylogeny and evolution are largely unknown.In this study,we analyzed plastomes from 27 species belonging to 2 subgenera and 3 sections of Eremurus,which are found in Central Asia(its center of diversity)and China.We also analyzed nuclear DNA ITS of 33 species,encompassing all subgenera and sections of the genus in Central Asia,southwest Asia and China.Our findings revealed that the genus was monophyletic,although both subgenera Eremurus and Henningia were found to be paraphyletic.Both plastome and nrDNA-based phylogenetic trees had three clades that did not reflect the current taxonomy of the genus.Our biogeographical and time-calibrated trees suggest that Eremurus originated in the ancient Tethyan area in the second half of the Eocene.Diversification of Eremurus occurred from the early Oligocene to the late Miocene.Paratethys Sea retreat and several orogenetic events,such as the progressive uplift of the Qinghai-Tibet Plateau and surrounding mountain belts(Altai,Pamir,Tian Shan),caused serious topographic and climate(aridification)changes in Central Asia that may have triggered a split of clades and speciation.In this transformed Central Asia,speciation proceeded rapidly driven mainly by vicariance caused by numerous mountain chains and specialization to a variety of climatic,topographic and soil conditions that exist in this region.

The Global Energy and Water Exchanges(GEWEX)Project in Central Asia:The Case for a Regional Hydroclimate Project

Central Asia consists of the former Soviet Republics,Kazakhstan,Kyrgyz Republic,Tajikistan,Turkmenistan,and Uzbekistan.The region’s climate is continental,mostly semi-arid to arid.Agriculture is a significant part of the region’s economy.By its nature of intensive water use,agriculture is extremely vulnerable to climate change.Population growth and irrigation development have significantly increased the demand for water in the region.Major climate change issues include melting glaciers and a shrinking snowpack,which are the foundation of the region’s water resources,and a changing precipitation regime.Most glaciers are located in Kyrgyzstan and Tajikistan,leading to transboundary water resource issues.Summer already has extremely high temperatures.Analyses indicate that Central Asia has been warming and precipitation might be increasing.The warming is expected to increase,but its spatial and temporal distribution depends upon specific global scenarios.Projections of future precipitation show significant uncertainties in type,amount,and distribution.Regional Hydroclimate Projects(RHPs)are an approach to studying these issues.Initial steps to develop an RHP began in 2021 with a widely distributed online survey about these climate issues.It was followed up with an online workshop and then,in 2023,an in-person workshop,held in Tashkent,Uzbekistan.Priorities for the Global Energy and Water Exchanges(GEWEX)project for the region include both observations and modeling,as well as development of better and additional precipitation observations,all of which are topics for the next workshop.A well-designed RHP should lead to reductions in critical climate uncertainties in policy-relevant timeframes that can influence decisions on necessary investments in climate adaptation.

Food security amid the COVID-19 pandemic in Central Asia:Evidence from rural Tajikistan

Food security has been long understudied in the context of Central Asia.We present an analysis examining household-level food demand for Tajikistan and assessing the magnitude of its food security changes during the COVID-19 pandemic.Based on an extensive household survey data set from Tajikistan,we estimate the expenditure,income,and price elasticities for nine food categories using the QUAIDS model.Then,we develop a microsimulation model using the estimated elasticities to assess the dual impact of declining remittance income and rising food prices stemming from the pandemic shock.There are significant differences in demand elasticities across food groups,with high elasticities observed for nutritious foods,such as meat,fruit,eggs,and milk,in rural households.Moreover,our findings show that changes in remittance income and food prices significantly negatively affected food security for rural households during the COVID-19 pandemic.These findings have important implications for policymakers concerned about rural livelihoods and food security in remittance-receiving economies during the post-pandemic period.

Increased population exposures to extreme precipitation in Central Asia under 1.5℃and 2℃global warming scenarios

The increase in extreme precipitation(EP)may pose a serious threat to the health and safety of population in arid and semi-arid regions.The current research on the impact of EP on population in Central Asia(CA)is insufficient and there is an urgent need for a comprehensive assessment.Hence,we opted for precipitation and temperature data under two Shared Socioeconomic Pathways(SSP2-4.5 and SSP5-8.5)from ten Global Climate Models(GCMs),which were obtained from the NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP-CMIP6).By integrating population data in 2020 and 2050(SSP2 and SSP5),we investigated the future changes in EP and population exposure in CA under 1.5℃and 2℃global warming scenarios(GWSs).Our analysis indicates that EP in CA is projected to increase with global warming.Under the SSP5-8.5,the maximum daily precipitation(Rx1day)exhibits an average response rate to global warming of 3.58%/K(1.99-4.06%/K).With rising temperatures,an increasing number of areas and populations in CA will be impacted by EP,especially in the Fergana valley.Approximately 25%of the population(land area)in CA is exposed to Rx1day with increases of more than 8.31%(9.32%)under 1.5℃GWS and 14.18%(13.25%)under 2℃GWS.Controlling temperature rise can be effective in reducing population exposures to EP.For instance,limiting the temperature increase to 1.5℃instead of 2℃results in a 2.79%(1.75%-4.59%)reduction in population exposure to Rx1day.Finally,we found that climate change serves as the predominant factor influencing the population exposure to EP,while the role of population redistribution,although relatively minor,should not be disregarded.Particularly for prolonged drought,the role of population redistribution manifests negatively.

Population genetic insights into the conservation of common walnut(Juglans regia)in Central Asia

The common walnut(Juglans regia)is one of the most economically important nut trees cultivated worldwide.Despite its importance,no comprehensive evaluation of walnut tree population genetics has been undertaken across the range where it originated,Central Asia.In this study,we investigated the genetic diversity and population structure of 1082 individuals from 46 populations across Central Asia.We found moderate genetic diversity of J.regia across Central Asia,with 46 populations clustered into three groups with a weak relationship between genetic and geographic distance.Our findings reveal that the western Himalaya might be the core region of common walnut genetic diversity in Central Asia and that,except for two populations in Gongliu Wild Walnut Valley,humans might have introduced walnut populations to Xinjiang,China.The observed distribution of the genetic landscape has probably been affected by historical climate fluctuation,breeding system,and prolonged anthropogenic activity.We propose the conservation of the core genetic diversity resources in the western Himalaya and pay special attention to populations from Gongliu in Xinjiang.These findings enhance our understanding of the genetic variation throughout the distribution range of J.regia in Central Asia,which will provide a key prerequisite for evidence-based conservation and management.

Potential distribution of Haloxylon ammodendron in Central Asia under climate change

Understanding the spatial distribution of plant species and their dynamic changes in arid areas is crucial for addressing the challenges posed by climate change.Haloxylon ammodendron shelterbelts are essential for the protection of plant resources and the control of desertification in Central Asia.Thus far,the potential suitable habitats of H.ammodendron in Central Asia are still uncertain in the future under global climate change conditions.This study utilised the maximum entropy(MaxEnt)model to combine the current distribution data of H.ammodendron with its growth-related data to analyze the potential distribution pattern of H.ammodendron across Central Asia.The results show that there are suitable habitats of H.ammodendron in the Aralkum Desert,northern slopes of the Tianshan Mountains,and the upstream of the Tarim River and western edge of the Taklimakan Desert in the Tarim Basin under the current climate conditions.The period from 2021 to 2040 is projected to undergo significant changes in the suitable habitat area of H.ammodendron in Central Asia,with a projected 15.0% decrease in the unsuitable habitat area.Inland areas farther from the ocean,such as the Caspian Sea and Aralkum Desert,will continue to experience a decrease in the suitable habitats of H.ammodendron.Regions exhibiting frequent fluctuations in the habitat suitability levels are primarily found along the axis stretching from Astana to Kazakhskiy Melkosopochnik in Kazakhstan.These regions can transition into suitable habitats under varying climate conditions,requiring the implementation of appropriate human intervention measures to prevent desertification.Future climate conditions are expected to cause an eastward shift in the geometric centre of the potential suitable habitats of H.ammodendron,with the extent of this shift amplifying alongside more greenhouse gas emissions.This study can provide theoretical support for the spatial configuration of H.ammodendron shelterbelts and desertification control in Central Asia,emphasising the importance of proactive measures to adapt to climate change in the future.

Spatiotemporal characteristics and influencing factors of ecosystem services in Central Asia

Land use/land cover(LULC)change and climate change are two major factors affecting the provision of ecosystem services which are closely related to human well-being.However,a clear understanding of the relationships between these two factors and ecosystem services in Central Asia is still lacking.This study aimed to comprehensively assess ecosystem services in Central Asia and analyze how they are impacted by changes in LULC and climate.The spatiotemporal patterns of three ecosystem services during the period of 2000-2015,namely the net primary productivity(NPP),water yield,and soil retention,were quantified and mapped by the Carnegie-Ames-Stanford Approach(CASA)model,Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model,and Revised Universal Soil Loss Equation(RUSLE).Scenarios were used to determine the relative importance and combined effect of LULC change and climate change on ecosystem services.Then,the relationships between climate factors(precipitation and temperature)and ecosystem services,as well as between LULC change and ecosystem services,were further discussed.The results showed that the high values of ecosystem services appeared in the southeast of Central Asia.Among the six biomes(alpine forest region(AFR),alpine meadow region(AMR),typical steppe region(TSR),desert steppe region(DSR),desert region(DR),and lake region(LR)),the values of ecosystem services followed the order of AFR>AMR>TSR>DSR>DR>LR.In addition,the values of ecosystem services fluctuated during the period of 2000-2015,with the most significant decreases observed in the southeast mountainous area and northwest of Central Asia.LULC change had a greater impact on the NPP,while climate change had a stronger influence on the water yield and soil retention.The combined LULC change and climate change exhibited a significant synergistic effect on ecosystem services in most of Central Asia.Moreover,ecosystem services were more strongly and positively correlated with precipitation than with temperature.The greening of desert areas and forest land expansion could improve ecosystem services,but unreasonable development of cropland and urbanization have had an adverse impact on ecosystem services.According to the results,ecological stability in Central Asia can be achieved through the natural vegetation protection,reasonable urbanization,and ecological agriculture development.

Biostratigraphy,Microfacies,Sedimentary Environments and Sequence Stratigraphy of the Late Devonian-Carboniferous Deposits at the Anarak Section,Central Iran

The Late Devonian-early Carboniferous deposits of the Anarak section in northeastern Isfahan,Central Iran,evaluated based on conodont biostratigraphy,sedimentary environment and sequence stratigraphy.According to the field observations,five lithological units were identified.Investigating the conodont fauna of the Late Devonian-Carboniferous(Mississippian-Pennsylvanian)deposits of Bahram,Shishtu,and Qaleh(Sardar 1)formations in Anarak section led to the identification of 67 species of 18 conodont genera,and accordingly 22 conodont biozones were differentiated.The correlation of sea-level change curves,regarding to the conodont biofacies with the global sea-level curve,demonstrates the relative correlation in the mentioned times due to the shallow condition of the central Iran basin compared to the European and American basins.The microfacies analysis led to the identification of 12 microfacies related to the open sea,bioclastic barrier,lagoon and tidal flat sub-sedimentary environments in a homoclinal carbonate ramp environment.Based on sequence stratigraphy studies,three 3rd order sequences were identified.The first sequence,which is of the Late Devonian(upper part of the Bahram Formation,32.5 m),the second sequence(12.5 m)is the Late Devonian(uppermost part of the Bahram Formation),and the third sequence(68 m)is the early Carboniferous(the Shishtu I Formation).

Tectonic paleostress field and its impact on the geodynamic evolution of Central Iran, case study: the Shotori Mountain

The Shotori mountain range is located along the northern terminus of the Nayband fault on the eastern and western domains of the Tabas and Lut blocks,respectively.This range with NNW-SSE trending and approximately 120 km long includes a series of thrust faults approaching the right-lateral strike-slip Nayband fault.Since the Shotori range has experienced various geological events since the Triassic,our investigations suggest that the basement of the Central Iranian subcontinent of the Shotori range contains the early Triassic deep sedimentary with normal faults which confirms Triassic tensional tectonic stress regime in the region.After the middle Triassic,the mountain range has experienced thrust and strike-slip regimes.Therefore,in this study,we reconstruct the stress regimes for different geological periods using fault-slip data.The inversion of faultslip data reveals drastic temporal changes in the maximum stress regime(σ1)over the Triassic,Jurassic,Cretaceous,Paleogene,Neogen,and Quaternary.The reconstruction of the stress field based on the age and direction of fault movement reveals that the direction of the maximum horizontal stress axis(σ1)under a tensional stress regime was approximately N129°in the Early Triassic.This stress regime is the cause of thinning and subsidence of the Shotori sedimentary basin.During the middle Triassic,theσ1 direction was about N81°and the upper Triassic,theσ1 direction was almost N115°.The middle Triassic and upper Triassic stress states exhibited two distinct strike-slip and compressive stress regimes.This stress regime led to the uplift of the Shotori sedimentary basin.During the Jurassic,the direction of the maximum horizontal stress axis(σ1)was~NW-SE under a compressive stress regime.During the Triassic,theσ1 direction was~N-S.This stress regime led to the formation of the high topography of the Shotori Mountain Range.In the Late Cretaceous,the direction of the maximum horizontal stress axis(σ1)under the extensional stress regime was~NE-SW.This stress regime led to the uplift of the Paleogen Dacite in eastern Iran.During the Neogene,theσ1 direction was~N60°.The Quaternary tectonic regime is strike-slip and theσ1 direction is~N50°,consistent with the current convergence direction of the Arabia–Eurasia plates.Our paleostress analysis reveals four recognized stress in this area,which includes compressional,transtensional,transpressional,and strike-slip regimes.Our findings indicated that the crustal diversity of the tectonic regimes was responsible for the formation of various geological structures,such as folds,faults by different mechanisms,and the present-day configuration of the Shotori sedimentary basin.

Black Carbon Size in Snow of Chinese Altai Mountain in Central Asia

Black carbon(BC)in snow plays an important role to accelerate snow melting.However,current studies mostly focused on BC concentrations,few on their size distributions in snow which affected BC’s effect on albedo changes.Here we presented refractory BC(rBC)concentrations and size distributions in snow collected from Chinese Altai Mountains in Central Asia from November 2016 to April 2017.The results revealed that the average rBC concentrations were 5.77 and2.82 ng g-1for the surface snow and sub-surface snow,which were relatively higher in the melting season(April)than that in winter(November-January).The mass median volume-equivalent diameter of rBC size in surface snow was approximately at 120-150 nm,which was typically smaller than that in the atmosphere(about 200 nm for urban atmosphere).However,there existed no specific mass median volume-equivalent diameter of BC size for sub-surface snow in winter.While during the melting season,the median mass size of rBC in sub-surface snow was similar to that in surface snow.Backward trajectories indicated that anthropogenic sourced BC dominated rBC in snow(70%-85%).This study will promote our understanding on BC size distributions in snow,and highlight the possible impact of BC size on climate effect.

The role of natural resources in financial expansion:evidence from Central Asia

Central Asian States(CAS)have diverse natural resources.This research aims to shed light on the finance–natural resource’s association in the context of CAS namely Kazakhstan,Kyrgyzstan,Tajikistan,Turkmenistan,and Uzbekistan in 1996–2020 using the cross-sectionally augmented autoregressive distributed lag technique.It seeks to examine the research question,“What is the effect of natural resource wealth on the financial expansion(FE)of Central Asia?”The results demonstrated an inverted U-shaped association between financial growth and natural resource rents.It implies that natural resources are initially a“resource blessing”that later becomes a“resource curse.”Additionally,the effect of institutional quality(INQ)and human development(HD)on financial growth is examined.The results reveal that INQ and HD positively affect FE.Moreover,a bidirectional causal relationship exists between FE and INQ.Finally,all variables contribute to a long term FE.Based on these outcomes,the major policy recommendations are that the CAS authorities diversify their financial services and products and direct the proceeds from natural resource rents to effective invest-ments particularly in HD.In addition,the social and political infrastructures in CAS must be restructured to achieve a high-quality institutional environment,which is necessary to increase the role of the private sector.

Temporal and spatial variation of cloud cover in arid regions of Central Asia in the last 40 years

Water resources are one of the key factors restricting the development of arid areas,and cloud water resources is an important part of water resources.The arid region of central Asia is the core region of the current national green silk road construction,and is the largest arid region in the world.Based on cloud cover data of ECMWF,the current study analyzed temporal and spatial characteristics of cloud properties in arid regions of Central Asia between 1980 and 2019.Our findings show that:(1)From the point of view of spatial distribution,total cloudiness in arid regions of Central Asia was low in the south and high in the north.The distribution of high cloud frequency and medium cloud frequency was higher in the south and lower in the north,while low cloud frequency distribution was low in the south and high in the north.(2)In terms of time,the variation of cloud cover and cloud type frequency had obvious seasonal characteristics.From winter to spring,cloud cover increased,and the change of cloud type frequency increased.From spring to summer,cloud cover continued to increase and the change of cloud type frequency increased further.Cloud cover began to decrease from summer to autumn,and the change of cloud type frequency also decreased.(3)Generally,average total cloud cover decreased in most of central Asia,and high and medium cloud cover increased while low cloud cover decreased.This study provides a reference for the rational development of cloud resources in the region.

Synoptic-scale reversal of dipole surface temperature anomalies over East Asia and Central Siberia in November 2021

2021年11月,东亚与中西伯利亚经历了相反的冷暖异常转换,表现为“中西伯利亚偏冷,东亚偏暖”与“中西伯利亚偏暖,东亚偏冷”的交替出现.该偶极型气温异常的天气尺度反转伴随着大尺度大气环流异常的反转.进一步分析表明,东亚与中西伯利亚的偶极型气温异常反转是1979-2021年期间11月欧亚气温日变化的主导模态之一(发生概率超过56%).

Regional Stability for National Survival： Iran＇s Foreign Policy Towards the Southern Caucasus and Central Asia in the Post-Soviet Era

This paper focuses on Iran＇s foreign policy towards the Caucasus and Central Asia regions in the post-Soviet Union era, using a theoretical approach which stresses the importance of historical and geographical contextualization for the analysis of foreign policy. The article＇s main argument is that Iranian foreign policy towards these regions in the last 25 years, although the result of a complex and multi-layered decision-making process, has been led by two unifying long-term objectives： regional stability and national security. In order to demonstrate this argument, the article undertakes a factual analysis focusing on the role Iran played during the main regional conflicts that have occurred since the Soviet Union＇s collapse in Central Asia and the Caucasus, as well as the diplomatic re-engagement Iran has been building with the countries of these two regions after the end of the Iran nuclear deal. Standard interpretations of Iran＇s foreign policy define it as a player with hegemonic ambitions whose foreign policy is mainly led by ideological factors. This paper assumes that foreign policy＇s analysis needs time and space contextualization. Once historical and geographical factors are taken into account----of which the most important are Iran＇s proximity to Russia and Afghanistan along with its international diplomatic isolation due to nuclear sanctions--then Iran＇s foreign policy in Central Asia and the Caucasus appears to be that of a regional power interested in maintaining the existing status quo. Stability and territorial integrity in these two regions in fact are seen by Teheran as necessary conditions for Iran＇s own territorial integrity and internal security. The paper is based on both secondary and primary sources, most of them official statements, all in the public domain.

Climate change, water resources and sustainable development in the arid and semi-arid lands of Central Asia in the past 30 years

The countries of Central Asia are collectively known as the five "-stans": Uzbekistan, Kyrgyzstan, Turkmenistan, Tajikistan and Kazakhstan. In recent times, the Central Asian region has been affected by the shrinkage of the Aral Sea, widespread desertification, soil salinization, biodiversity loss, frequent sand storms, and many other ecological disasters. This paper is a review article based upon the collection, identification and collation of previous studies of environmental changes and regional developments in Central Asia in the past 30 years. Most recent studies have reached a consensus that the temperature rise in Central Asia is occurring faster than the global average. This warming trend will not only result in a higher evaporation in the basin oases, but also to a significant retreat of glaciers in the mountainous areas. Water is the key to sustainable development in the arid and semi-arid regions in Central Asia. The uneven distribution, over consumption, and pollution of water resources in Central Asia have caused severe water supply problems, which have been affecting regional harmony and development for the past 30 years. The widespread and significant land use changes in the 1990 s could be used to improve our understanding of natural variability and human interaction in the region. There has been a positive trend of trans-border cooperation among the Central Asian countries in recent years. International attention has grown and research projects have been initiated to provide water and ecosystem protection in Central Asia. However, the agreements that have been reached might not be able to deliver practical action in time to prevent severe ecological disasters. Water management should be based on hydrographic borders and ministries should be able to make timely decisions without political intervention. Fully integrated management of water resources, land use and industrial development is essential in Central Asia. The ecological crisis should provide sufficient motivation to reach a consensus on unified water management throughout the region.

Oil and gas cooperation between China and Central Asia in an environment of political and resource competition

This paper investigates Central Asia＇s oil and gas resources, special geopolitics and energy competition, and approaches, challenges and prospects in cooperation between China and Central Asia. The objective is to propose measures for oil and gas cooperation between China and Central Asia. Central Asia is rich in oil and gas resources. Its remaining recoverable reserves of crude oil and natural gas account for 1.9% and 10.6 %, respectively, of the world＇s total reserves. Moreover, there is great exploration and development potential. As a strategic channel connecting Eurasia, Central Asia has a prominent geopolitical status. Many powerful countries such as the United States, Russia and China, as well as Europe, have an intense energy competition in Central Asia. In the oil and gas cooperation with Central Asia, the China National Petroleum Corporation （CNPC） focuses on establishing a coordination group, promoting overall oil and gas business opportunities and sustainable development, innovating and applying specialty engineering technology and improving project economic benefits. Through its efforts over the last nearly two decades, the China National Petroleum Corporation has completed a 50-million-tonne a year oil and gas production centre in Central Asia and oil and gas pipelines passing through multiple countries, becoming an important channel for securing China＇s energy imports. If appropriate measures are taken in the ＇Thirteenth Five-Year Plan＇ period or later, the China National Petroleum Corporation will develop a 100-million-tonne p.a. oil and gas production centre in Central Asia and a strategic oil and gas import channel exceeding this amount of production. This cooperation between China and Central Asia is however faced with the following challenges： increasing multinational competition uncertainty, potential risks in the political systems of Central Asian countries, frequently occurring violence and also resource policy tightening in Central Asia. To further oil and gas cooperation with Central Asia, it is recommended that China should develop an energy acquisition strategy, assign a regional energy ambassador, enhance oil and gas supply by mergers and acquisitions, establish regional multinational subsidiaries and improve its risk prevention system.

Precipitation isotopes in the Tianshan Mountains as a key to water cycle in arid central Asia

The Tianshan Mountains is a wet island in arid central Asia, and precipitation amount across the mountains is much larger than that in the surrounding low-lying areas. To investigate the regional water cycle in arid central Asia, stable isotope composition in precipitation has received increased attention during the past decades. This paper reviewed current knowledge of observed and simulated stable isotope ratios in precipitation across the Tianshan Mountains. The temperature effect of stable isotopes in precipitation has been widely accepted in arid central Asia and can be applied to paleoclimate reconstruction using ice cores. The seasonality of precipitation isotopically enriched in summer months and depleted in winter months is usually attributed to westerly-dominated moisture, but different trajectory paths to the northern and southern slopes of the Tianshan Mountains can still be modelled. The proportional contribution and its uncertainty of surface evaporation and transpiration to local precipitation can be estimated using the isotope approach, and transpiration plays a dominant role in recycled moisture for oasis sites. The impact of below-cloud evaporation on precipitation stable isotopes on the southern slope is usually larger than that on the northern slope.

Precipitation trends and variability from 1950 to 2000 in arid lands of Central Asia

Climate warming will cause differences in precipitation distribution and changes in hydrological cycle both at regional and global scales. Arid lands of Central Asia （ALCA）, one of the largest arid regions at the middle latitudes in the world, is likely to be strongly influenced by climate warming. Understanding the precipitation varia- tions in the past is an important prerequisite for predicting future precipitation trends and thus managing regional water resources in such an arid region. In this study, we used run theory, displacement, extreme deviation theory, precipitation concentration index （PCI）, Mann-Kendall rank correlation and climatic trend coefficient methods to analyze the precipitation in wet and dry years, changes in precipitation over multiple-time scales, variability of precipitation and its rate of change based on the monthly precipitation data during 1950-2000 from 344 meteorological stations in the ALCA. The occurrence probability of a single year with abundant precipitation was higher than that of a single year with less precipitation. The average duration of extreme drought in the entire area was 5 years, with an average annual water deficit of 34.6 mm （accounting for 11.2% of the average annual precipitation over the duration）. The occurrence probability of a single wet year was slightly higher than that of a single dry year. The occurrence probability of more than 5 consecutive wet years was 5.8%, while the occurrence probability of more than 5 consecutive dry years was 6.2%. In the center of the study area, the distribution of precipitation was stable at an intra-annual timescale, with small changes at an inter-annual timescale. In the western part of the study area, the monthly variation of precipitation was high at an inter-annual timescale. There were clear seasonal changes in precipitation （PC1=12-36） in the ALCA. Precipitation in spring and winter accounted for 37.7% and 24.4% of the annual precipitation, respectively There was a significant inter-annual change in precipitation in the arid Northwest China （PC1=24-34）. Annual precipitation increased significantly （P=0.05） in 17.4% of all the meteorological stations over the study period. The probability of an increase in annual precipitation was 75.6%, with this increase being significant （P=-0.05） at 34.0% of all the meteorological stations. The average increasing rate in annual precipitation was 3.9 mm/10a （P=0.01） in the ALCA. There were significant increasing trends （P=0.01） in precipitation in Kazakhstan, Kyrgyzstan and Tajikistan, with rates of 2.6, 3.1 and 3.7 mm/10a, respectively.

Tectonics and Mineralisation of Copper in the Ardestan-Kahang Area, Central Iran by Remote Sensing

The Ardestan-Kahang area is located in Urmieh-Dokhtar Magmatic Arc. This area is situated in Ardestan, Kouhpayeh, Kajan and Zefreh in 1:100,000 geological maps. In order to extract mineralization zones related to copper mineralization and accessories elements, and also identify Argillic, Prophylitic, Sericitic and Siliceous alteration with major and minor lineaments, various kinds of algorithms, band ratio and personal interpolation have been utilized. The applied methods for extracting alteration consist of LS-Fit (Least Square Fit), Matched Filtering (MF), Spectral Angle Mapper (SAM) and Spectral Feature Fitting (SFF), band ratio and visual interpretation. Comparing different outputs of utilized algorithms illustrates that the best algorithm for argillc alteration extraction are Matched Filtering (MF) and Spectral Feature Fitting (SFF), with visual interpretation, and for argillic alterations the visual interpretation with RGB: 468 that has seen pink-red color. For prophylitic alterations the utilized algorithms are Matched Filtering (MF). Lineaments have extracted with visual interpretation on satellite images and it is revealed that in areas where the fracture density is greater, conditions are more suitable for copper mineralization.

Influence of the Asian-Pacific Oscillation on Spring Precipitation over Central Eastern China

The linkage between the Asian-Pacific oscillation （APO） and the precipitation over central eastern China in spring is preliminarily addressed by use of the observed data. Results show that they correlate very well, with the positive （negative） phase of APO tending to increase （decrease） the precipitation over central eastern China. Such a relationship can be explained by the atmospheric circulation changes over Asia and the North Pacific in association with the anomalous APO. A positive phase of APO, characterized by a positive anomaly over Asia and a negative anomaly over the North Pacific in the upper-tropospheric temperature, corresponds to decreased low-level geopotential height （H） and increased high-level H over Asia, and these effects are concurrent with increased low-level H and decreased high-level H over the North Pacific. Meanwhile, an anticyclonic circulation anomaly in the upper troposphere and a cyclonic circulation anomaly in the lower troposphere are introduced in East Asia, and the low-level southerly wind is strengthened over central eastern China. These changes provide advantageous conditions for enhanced precipitation over central eastern China. The situation is reversed in the negative phase of APO, leading to reduced precipitation in this region.