Spatial integration of oasis city group around the western margins of the Tarim Basin

In this paper,the oasis cities in Kashgar Prefecture and Kizilsu Kirgiz Autonomous Prefecture are taken as an example,through the factor analysis,spatial attraction interaction model and location quotient methods,urban hierarchy system,the intensity of urban economic ties,economic subordination degree,and structure of city functions were analyzed. The results indicated:(1) The urban hierarchy system takes Kashgar city as the main center,Artux city,Yarkant county and Maralbexi county as the sub-centers; (2) The intensity of economic ties among Kashgar city and each county is much higher than others. The interaction of Kashgar city,Shufu county and Shule county are the strongest,and the economic ties of Yarkant,Kagilik,Poskam counties are relatively close; All cities in the study area are economically subordinate to Kashgar city. (3) Three cities of Kashgar city,Shufu county and Shule county should connect strongly,with Kashgar city as the core. The cities and towns along the Southern Xinjiang Railway and along National Road 315 should be regarded as two strips,and the two city strips along the border,and the city strip along Provincial Road 215 should be treated as three axes. The ring structure strategy of 'core ring,closer ring and radiated ring' was proposed. (4) It was proposed to build Kashgar city group in the north,and Yarkant city group in the south,Maralbexi city group in the southeast,and Taxkorgan border city group with four inner groups’ development strategy.

Evolution Stages of Oasis Economy and Its Dependence on Natural Resources in Tarim River Basin

This paper examines spatio-temporal characteristics of an oasis economy and its relationship with water and mineral resources in the Tarim River Basin from 1965 to 2005. A spatial autocorrelation model, the center of gravity model, and index system of the regional central city are used to probe the evolution laws of spatial structure of oasis economy. The study finds that: 1) The economic centre of gravity, whose variation track during this period follows linear rate law, was moving from headstream to middle reaches of the Tarim River. 2) Positive spatial autocorrelation which showed a waving and ascending trend of regional economy was significant and the neighbor effect of regional economic growth was strengthened continuously. 3) The regional economic centre was located in Hotan City before 1980, moved to Aksu City during the 1980s and to Korla City after 1990. We conclude that above all, during the recent four decades the evolution of the oasis economy in this region has gone through three stages: a traditional agriculture stage (before 1980), oasis agriculture and agricultural product processing stage (1980–1990) and oasis energy industry stage (after 1990). Furthermore, the dependence degree of the oasis economy on natural resources in different stages are studied by using dominance index, regression model, and grey relation method, which shows that an oasis econ- omy highly depends on water resources in the oasis agriculture and agricultural product processing stage while it de- pends more on mineral resources such as oil and natural gas during the oasis energy industry stage.

THE UTILIZATION OF WATER RESOURCE AND THE OASIS ECONOMIC DEVELOPMENT IN ARID LAND—A CASE STUDY OF TURPAN BASIN

Turpan Basin is a unique geographic region in China. The topography of the Basin is closed and the climate is extremely dry. The shortage of water resource has been restricting the existence and development of the oasis in Turpan Basin. This paper briefly analyzes the characteristics of the basin's water resources, and expounds the processes of their utilization and regional development. It points out that the exploration of water resource is close to the limit and the utilization of water resource is unreasonable. So it is nonrealistic to follow the traditional exploration pattern. According to the transforming pattern between runoff and groundwater in the basin, an overall planning of the utilization of the water resource is advanced. Based on the relation between the maintenance of Aydingkol Lake and the existence of the oasis, the amount of water resource used must be controlled in order to guarantee the existence of the lake. The orientation of the utilization of water resource is to improve the management level of water resource, and to apply advanced water saving technology. Building up an economic system which can effectively use water resource is the orientation of the oasis sustainable economic development.

ON EVOLUTION OF MAN-LAND SYSTEM IN OASIS-Taking Minqin Basin as a Case

Human beings have had a tremendous i mpact on natural ecosystems and are n ow the principal power to change the biosphere.It is logical t hat we should pay close attention to t he interaction between human system s and environ-mental systems.Taking Minqin basin,Gansu Province,as a case,this paper focuses on the evolution of regional physi-cal environments and the cultural sy stems by which people maintain their relationships with those environme nts.This pa-per presents the conceptual framewo rk for the man-land system.Expectin g to accelerate the regional sustain able develop-ment,it also analyses the evolution ary mechanism of regional man-land s ystem.On the basis of reviewing and a nalyzing the evolution of man-land system in Minqin basin,the paper also brings fo rward an adjusting mode for the studi ed area,which consists of three aspects:to b uild up a concept that economic growt h must harmonize with environmental quality’s and land productivity’s improvemen t;to make a whole planning and management in the drainage area;and to push for-ward the technique of water-saving i rrigation and establish water-saving agricultural system.It’s meanin gful for resource exploitation and sustainable development of Chinese northwestern arid area,which is represented by Minqin basin,by under-standing what great changes the basin has experienced and is experiencin g at the global background,and studying its time order and territorial structure,th e system’s character and law of evolu tion,trend and the regulating ways t o improve man-land relationship.

AREAL DIFFERENTIATION AND CONSTRUCTION OF OASIS AGRICULTURAL ECOSYSTEM IN THE SHIYANG RIVER BASIN

On the basis of the study on areal differentiation of the natural environment of oasis agriculture ecosystems in the Shiyang River Basin, this paper comparatively analyzes the natural productivities, water economic benefits, production efficiency, ecological stabilities and developmental conditions of the Wuwei Oasis agricultural ecosystem in the middle reaches of the river basin and the Minqin Oasis agricultural ecosystem in the lower reaches. Under a same management level and investment of . material and energy, primary productiveness and economic benefits of the former are higher than those of the latter. Construction directions of Wuwei and Minqin oases should be different in order to alleviate the water- use contradiction between the middle and lower reaches. The construction objective of Wuwei Oasis should be efficient irrigated farming production system and Minqin Oasis should become a mixed forestry-pastoral-farming ecosystem taking ecological protection as its major function.

WATER RESOURCES AND OASIS CONSTRUCTION IN TARIM BASIN

Based on the description of the main characteristics of water resources in Tarim Basin, the paper discusses the relationships between utilization of water resources and oasis construction, and the protection and development of the oasis in Tarim Basin,

Hydrochemical characteristics and evolution of groundwater in the dried-up river oasis of the Tarim Basin,Central Asia

Intense human activities in arid areas have great impacts on groundwater hydrochemical cycling by causing groundwater salinization.The spatiotemporal distributions of groundwater hydrochemistry are crucial for studying groundwater salt migration,and also vital to understand hydrological and hydrogeochemical processes of groundwater in arid inland oasis areas.However,due to constraints posed by the paucity of observation data and intense human activities,these processes are not well known in the dried-up river oases of arid areas.Here,we examined spatiotemporal variations and evolution of groundwater hydrochemistry using data from 199 water samples collected in the Wei-Ku Oasis,a typical arid inland oasis in Tarim Basin of Central Asia.As findings,groundwater hydrochemistry showed a spatiotemporal dynamic,while its spatial distribution was complex.TDS and δ18O of river water in the upstream increased from west to east,whereas ion concentrations of shallow groundwater increased from northwest to southeast.Higher TDS was detected in spring for shallow groundwater and in summer for middle groundwater.Pronounced spatiotemporal heterogeneity demonstrated the impacts of geogenic,climatic,and anthropogenic conditions.For that,hydrochemical evolution of phreatic groundwater was primarily controlled by rock dominance and evaporation-crystallization process.Agricultural irrigation and drainage,land cover change,and groundwater extraction reshaped the spatiotemporal patterns of groundwater hydrochemistry.Groundwater overexploitation altered the leaking direction between the aquifers,causing the interaction between saltwater and freshwater and the deterioration of groundwater environment.These findings could provide an insight into groundwater salt migration under human activities,and hence be significant in groundwater quality management in arid inland oasis areas.

Vulnerability and adaptation of an oasis social–ecological system affected by glacier change in an arid region of northwestern China

The Hexi Inland River Basin in an arid region of northwestern China was chosen as the study area for this research. The authors define the vulnerability of an oasis social-ecological system to glacier change; select 16 indicators from natural and socioeconomic systems according to exposure, sensitivity, and adaptive capacity; and construct a vulnerability-assessment indicator system aimed at an inland river basin in the arid region of Northwestern China. Vulnerability of the oasis socialecological system affected by glacier change in the study area is evaluated by Spatial Principal Component Analysis(SPCA) under the circumstance of glacier change. The key factors affecting the vulnerability are analyzed. The vulnerability of the oasis social-ecological system in the Hexi Inland River Basin affected by glacier change is of more than medium grade, accounting for about 48.0% of the total number of counties in the study area. In terms of the spatial pattern of the vulnerability, the oasis economic belt is the most vulnerable. With the rapid development of the area's society and economy, the exposure of the system to glacial changes is significantly increased; and an increase in glacial meltwater is not enough to overcome the impact of increased exposure, which is the main reason for the high vulnerability. Based on the result of the vulnerability analysis and combined with the present industrial structure in the Hexi Inland River Basin, near-,medium-, and long-term adaptation initiatives are put forward in the article.

塔里木河流域水储量变化及绿洲生态安全评估

绿洲是干旱、半干旱地区最具生态敏感性和独特性的景观类型,是维系人类生存和社会经济发展的重要区域。然而,在气候变化与人类活动双重影响下,干旱区水资源及其绿洲生境正发生剧烈变化。基于2000—2020年MODIS、GRACE卫星数据、土地利用数据和气象观测资料,通过计算植被覆盖度,估算植被初级生产力(NPP)和遥感生态指数(RSEI),系统分析了过去20 a塔里木河(简称塔河)流域陆地水储量和绿洲的动态变化并完成了绿洲区生态安全评估。结果表明:(1)2002—2020年塔河流域陆地水储量以0.27 mm·月-1的速率减少,空间上塔河流域陆地水储量在北部和西部区域显著减少,而在南部区域显著增加。(2)2000—2020年塔河流域绿洲面积显著增加,面积增加6.49%(0.42×10^(4)km^(2))。塔河流域整体生态环境呈转好趋势,生态等级由较差级别转为中等级别,生态改善区占总流域面积的69%,而生态退化区面积不足5%。塔河流域归一化植被指数(NDVI)由2000年的0.13增至2020年的0.16,近20 a植被覆盖度增加36.79%,NPP增加31.55%。(3)气温升高和降水增多的同时伴随下游河川径流增加,这进一步加剧了塔河流域陆地水资源储量的时空差异性,但人类活动仍是绿洲显著扩张最根本的原因。

近47年吐鲁番盆地人工绿洲精明增长的时空过程分析

以1976、1990、2000、2010、2023年5期Landsat遥感影像进行解译,借助数理统计模型、分形维数、紧凑度指数等方法,结合精明增长理论,构建了绿洲精明增长指标体系,测度并分析了近47年吐鲁番盆地人工绿洲的扩张及分布情况以及绿洲精明增长水平的时空表现。结果表明:(1)吐鲁番盆地绿洲规模空间扩张态势明显,呈现出明显的阶段性特征,绿洲面积由1976年的1259.33 km^(2)扩张至2023年的1810.27 km^(2);其扩展强度在经历缓慢下降—慢速增长—快速增长后转变为精明增长背景下的中低速增长。(2)吐鲁番盆地绿洲空间扩张方向具有分异性,扩张方向以西北、东北最为显著,空间重心迁移轨迹为西南—东北—西南,最大迁移距离为55.60 km。(3)在研究时间段内绿洲紧凑度维持在较高水平,土地利用率较高,但近10年呈现下降趋势;空间扩张模式呈现蔓延式—跳跃式—填充式的演变特征。(4)吐鲁番盆地的绿洲精明增长水平较低,精明得分由1976年的0.474下降至1990年的0.383,随后回升,2023年达到最大值0.517;从精明增长水平的空间差异看,以大河沿—塔尔朗流域下游、托克逊—白杨河流域下游为高水平的双核心趋势明显,呈现由中心向四周波动递减的态势。研究结果可为未来绿洲区的合理发展,防止绿洲无序蔓延扩张,保障干旱区绿洲土地资源的合理配置提供参考依据。

塔里木盆地绿洲带地下水咸化机制

采用Durov图、PMF模型、Gibbs图、离子比值法和饱和指数法对2016~2018年采集的1326组地下水样品进行分析,揭示研究区地下水中盐分的来源及高盐地下水形成的驱动因素.结果表明:在研究区绿洲带微咸水和咸水占比分别为37.2%和19.1%,水化学类型主要为SO_(4)·Cl型;在微咸水、咸水、盐水和卤水中岩盐、石膏等蒸发盐岩的持续溶解是导致高盐地下水形成的主要驱动因素,Cl^(-)、SO_(4)^(2-)、 Na^(+)与TDS(P<0.001)及岩盐、石膏的SI值与TDS(P<0.001)之间均呈现出极显著的正相关性,也证实了这一点;冲积平原区较差的地下水动力条件、细粒岩性和弱碱性的水化学环境为地下水中盐分的富集创造了有利条件,蒸发浓缩作用和阳离子交换作用是形成高盐地下水的次要因素;由于人类活动的影响,导致承压水区高TDS潜水沿井壁入渗补给承压水含水层,也是加剧深层地下水咸化的潜在因素.

塔里木盆地东北缘绿洲区土壤养分特征及主控因素分析

土壤健康关系人民生产生活水平,关乎国家粮食安全,是重要的战略资源。为摸清塔里木盆地东北缘典型绿洲区土壤养分特征,采集研究区土壤表层样品140件,测定主要养分元素含量,分析其生态化学计量特征、空间分布规律及影响养分富集的主控因素。结果表明:①研究区Fe、Mn含量高值分布面积最广,Mg含量高值分布范围最小;分析土壤生态化学计量特征,发现缺氮少磷是限制区内植物正常生长的主控因素。②从数量上来看,研究区贫瘠、极贫瘠级别的土地面积占总面积的99.14%,仅0.86%的土地处于中等级别水平。从空间分布上来看,中等肥力的土地分布在区内东南部,呈孤岛状;极贫瘠的土地主要分布在绿洲-荒漠的过渡带上。③研究区4种土地利用方式中,耕地的土壤养分含量较高;土壤养分元素的含量与坡向、地表粗糙度呈正相关关系,与海拔呈负相关关系。同时,土壤养分的丰缺与长期连作、作物施肥、灌溉技术等人为影响也有着密切的关系。

干旱区绿洲-城镇-荒漠景观演变及生态环境效应

绿洲、城镇和荒漠是干旱区内陆河流域重要的景观类型,随着流域社会经济发展,干旱区生态环境问题日益凸显。本研究选取我国西北干旱区第二大内陆河——黑河流域内绿洲-城镇-荒漠的景观组合作为研究对象,利用景观转型核密度与景观结构指数分析2000—2020年期间黑河流域绿洲-城镇-荒漠的时空格局与转型特征,借助多元回归树(MRT)模型探究三类景观转型之间的权衡-协同关系,基于遥感生态指数(RSEI)与景观转型生态贡献率揭示绿洲-城镇-荒漠景观转型的生态环境效应。结果显示:(1)黑河流域荒漠广布,绿洲仅在中下游河道沿岸集中分布,城镇面积占比最小,其空间分布和规模结构与绿洲有紧密关联;(2)黑河流域绿洲-城镇-荒漠景观转型可概括为:农业活动主导期(2000—2005年)、产业快速发展期(2005—2015年)和发展转型协调期(2015—2020年);(3)气温、GDP、海拔、降水量是影响绿洲-城镇-荒漠景观转型之间权衡-协同关系的主要因素;(4)2000—2020年期间流域景观转型以正的生态环境效应为主,耕地扩张是正效应的主导因素;耕地退化、水域减少与草地退化则是带来负效应的主要因素。研究结果可为干旱区内陆河流域实施生态保护与高质量发展提供理论指导。

玛纳斯河流域绿洲农区残余盐渍化土壤质量评价

土壤质量评价对于评估土壤的现状与生产力、促进农业可持续发展、保护生态环境具有重大意义。通过分析玛纳斯河流域绿洲下属的7个灌区内盐渍化土壤理化性质,采用主成分分析法对玛纳斯河流域绿洲农区残余盐渍化土壤质量进行评价。结果表明:(1)影响玛纳斯河流域绿洲农区土壤质量的最小数据集包括土壤总盐、有机质、pH值、Na^(+)、Mg^(2+)、碱解氮和土壤质地;(2)绿洲农区土壤养分丰富度依次为:速效钾、有效磷、碱解氮、有机质;(3)绿洲农区土壤质量以Ⅱ级[0.65<土壤质量综合评价指数(IFI)≤0.85]、Ⅲ级(0.45<IFI≤0.65)为主,分别占绿洲农区总面积的47.30%、36.44%;(4)流域内莫索湾灌区和石河子灌区盐渍化土壤质量最优,其余依次为玛纳斯灌区、金沟河灌区、安集海灌区、下野地灌区和新湖总场灌区。综上所述,研究区内土壤养分较为匮乏,土壤盐分分布不均匀,土壤质量总体处于中等偏下状态,应当分区域制定土壤地力提升措施以保障流域内农业的可持续发展。

Spatio-temporal analysis of urbanization and land and water resources efficiency of oasis cities in Tarim River Basin

This paper examines the spatial pattern of land and water resources as well as urbanization and their interactions in the Tarim River Basin, Xinjiang, China. In order to do so, we extract the data associated with efficiency of land and water resources and urbanization for the years of 1995, 2000, 2005 and 2008. Specifically the paper investigates the extent to which agglomeration of population and economic activities varies geographically and inter- plays with spatial pattern of resources efficiency through computation of Global Moran＇s I index, Getis-Ord Gi＊ index and a coordinated development model. The method used provides clear evidence that urbanization, land and water resources efficiency have shown uneven spatial pattern due to oasis distribution, climate, and initial phase of urban development. Some conclusions can be drawn as follows. （1） Agglomeration and dispersion of urbanization are not consistent with those of land and water resources efficiency. （2） Evolution of the hot and cold spots of urbanization, and land and water resources efficiency, in different trajecto- ries, indicate that there are no significant interactions between them. （3） The evidence that numbers of hot and cold spots of the three factors present varying structures reveals the dominance of unequal urban development in the study area. （4） Significant differences are also found between sub-river basins in terms of the three factors, which is a reflection of the complex physical geography of the area. （5） The degree of coordinated development of cities in the Tarim River Basin is generally low in part as a reflection of difference in spatial patterns of the three factors. It is also shown that the pattern of the degree of coordinated development is relatively stable compared with evolution of hot and cold spots of the three factors.

An analysis of oasis evolution based on land use and land cover change： A case study in the Sangong River Basin on the northern slope of the Tianshan Mountains

This study investigated oasis evolution and the changes of peripheral desert in the Sangong River Basin since the 1950 s by rebuilding seven land cover maps derived from black-and-white aerial photographs（1958, 1968, and 1978）, a color-infrared aerial photograph（1987）, Landsat Thematic Mapper（TM） imagery（1998）, Satellite Pour l＇Observation de la Terre（SPOT） imagery（2004）, and Landsat Operational Land Imager（OLI） imagery（2014）. The results showed that：（1） Since 1950, the oasis consecutively expanded more than four times from an alluvial fan to an alluvial plain, causing the shrinkage of desert landscapes that were dominated by a Haloxylon ammodendron Bunge community（HBC） and a Tamarix chinensis Lour community（TLC）. Furthermore, the primary（1958–1968） and final（2004– 2014） stages were the most important periods, during which agricultural land experienced the most rapid expansion during the period 1958–1968, and the built-up area showed the most rapid expansion after the 2000 s.（2） Two basic management modes, a ＂local mode＂ formed by the local governments and a ＂farm management mode＂ developed by Xinjiang Production and Construction Corps, together promoted oasis evolution under various land-use and landcover（LULC） stages.（3） The evolution of the modern oasis during the 1950s–2004 showed the general features of an arid oasis, while during the period of 2004–2014 it was characterized by a large-scale inter-basin water diversion or the import of new water sources.（4） The oasis expanded at the expense of desert vegetation, resulting in distinct variation in the structure of the desert plant community, which will make it more difficult to protect the desert ecosystem.

2012年张掖绿洲-荒漠区域水热碳通量及气象要素观测矩阵数据集

绿洲-荒漠生态系统是干旱/半干旱区特有景观,其水热碳通量的观测和研究对绿洲稳定与可持续发展具有重要的意义。本研究以黑河流域中游甘肃张掖绿洲-荒漠区域为研究对象,基于2012年在该区域开展的国际领先的通量观测矩阵试验,整理了观测试验获取的水热碳通量和气象要素数据,包括30 km×30 km和5.5 km×5.5 km两个嵌套的矩阵内21个观测点共22套涡动相关仪和21套自动气象站,4组大孔径闪烁仪和3组植物液流仪,观测项目包括生态系统净碳交换量、潜热通量、感热通量、空气温度、空气相对湿度、风速、风向、向下/上短波辐射、向下/上长波辐射、净辐射、大气压、降水、红外辐射温度、光合有效辐射、土壤温度、土壤水分、土壤热通量、平均土壤温度、树木蒸腾等。本数据集经过了严格的数据质量控制,可用于研究绿洲荒漠区域水热碳通量变化特征及影响机制,并为模式模拟或遥感估算结果等提供可靠的验证数据。

环塔里木盆地绿洲文化的形成与表现特质研究

环塔里木盆地独特的绿洲地理环境是该区域绿洲文化赖以成型的土壤与源泉,而作为绿洲文化的载体,绿洲诸群体在这里生存、繁衍、消逝、融合的漫长过程中,创造了属于环塔里木盆地独有的、具有多元性和开放性的绿洲文化。环塔里木盆地绿洲文化的表现特质包括四个方面:自成一体、连接东西的地形特点;农耕为基、牧商为辅的生产方式;族际混同、休戚与共的群体关系和交融共存、本土倾向的思想观念。

2015-2020年准噶尔盆地南缘荒漠绿洲交错带土地沙化敏感性时空变化

为探讨准噶尔盆地南缘荒漠绿洲交错带土地沙化的变化规律,选取干燥度指数、起沙风天数、土壤质地、植被覆盖度4个因子作为评价指标,基于多源数据开展准噶尔盆地南缘荒漠绿洲交错带2015—2020年土地沙化敏感性空间分布格局及其动态变化研究。结果表明:2015、2020年准噶尔盆地南缘荒漠绿洲交错带67%~70%的评估区域土地沙化敏感性处于敏感等级,一般敏感占评价区总面积的28%~31%,极敏感等级面积不足3%,主要发生在研究区东部戈壁区域。总体上,2015—2020年准噶尔盆地南缘荒漠绿洲交错带土地沙化敏感性除巴里坤山南部戈壁区域、奇台县、吉木萨尔县、克拉玛依局部区域、乌苏市西北角外,其余变化区域均由敏感性高等级向低等级转化,土地沙化敏感性呈改善趋势。