What are the keys to influence the life satisfaction of eco-migrants in the northern foot of the Qilian Mountains?A test based on the livelihood risk interaction

Eco-migrants'ability to adapt to livelihood risks and their satisfaction with lives directly affect the ecological and economic benefits of ecological migration engineering.To formulate an effective livelihood risk prevention system and welfare guarantee mechanism,we took the ecomigrants in Wuwei City as an example,developed an integrated analytical framework for life satisfaction and employed linear regression models to identify the interactions between livelihood risk and life satisfaction.Our findings indicate that 94.66%of eco-migrants in Wuwei City are threatened by livelihood risks after relocation.High living expenses,poor quality of redistributed production goods,and re-poverty constitute the main risks.The risk multiplicity index is 2.96.Besides cultural types,there are no significant differences in regions and livelihoods.A total of 55.73%of eco-migrants are satisfied with their lives,with the Liangzhou district scoring the highest.Except for satisfaction with development potential and public services,no significant intergroup differences were found among regions and livelihood patterns.Eco-migrant's life satisfaction is significantly affected by livelihood risks.Eco-migrants'satisfaction with living income,social integration,farmer-friendly policies and overall life is negatively affected by the risk of repoverty and inadequate social security.An ecomigrant's satisfaction with development potential and community construction is not influenced by one type of risk alone,but the interaction between risks has a strong influence.The interaction of welfare risks with economic risks and policy risks will balance and weaken the adverse effects of a single risk on those elements in the economic and policy spheres.This study offers novel ideas for rural revitalization,hollow governance,and well-being assurance.

Temporo-Spatial Distribution and Evolution of Ore Deposits in the West Sector of the Northern Qilian Mountains

The west sector of the northern Qilian Mountains is well-known for the Jingtieshan-type iron deposits. A new breakthrough has been made in prospecting for gold and copper in recent years. In this paper, the distribution characteristics of ore deposits in the study area are discussed from the viewpoint of tectonic evolution. It is suggested that there are 9 stages of mineralization from the Palaeoproterozoic to Indosinian. Four minerogenetic series and two minerogenetic subseries of ore deposits are recognized. Iron mineralization occurred in several stages, while most of the metals were accumulated in large amounts in the Caledonian. The enrichment and mineralization of gold is related to large-scale shear-strike-slip faults and the ascent and unloading of deep-seated fluids.

The Carboniferous at the Northern Foot of the Dabie Mountains and Its Tectonic Implications

In the Qinling orogenic belt. oceanic crust originated in the Early Palaeozoic. while the product of conti-nental collision appeared as late as after the Triassic. The Late Palaeozoic records there are of major impor-tance for understanding the tectonic regime at that time. The Carboniferous and even Permian sequences andthe distribution of sedimentary facies in northern Huaiyang indicate that the rocks were formed in a large basinopening towards the south. Regional stratigraphic correlation shows that the interior of the Qinling orogenicbelt was a sea trough lying between the Yangtze and North China plates in the middle part of the LatePalaeozoic. With subsequent northward migration of the South China Sea, the two seas were connected witheach other. Both the melanges and the Dabie block ia the eastern sector of the Qinling belt were formed in theMesozoic ?.

Space Structuring of the Northern Foot of the Qinling Mountains(Xi'an Section) based on Landscape City

Northern foot of the Qinling Mountains(Xi'an Section) is a transitional section between the Qinling Mountains and Xi'an City, so it has great ecological signifi cance. On the basis of sorting out landscape city, space structuring of the northern foot of the Qinling Mountains was studied within the theoretical framework of landscape city, it was disclosed that northern foot of the Qinling Mountains was a signifi cant ecological screen for the landscape city spatial pattern of Xi'an, and an important carrier for its "mountain, water and city" cultures. Then, fi ve infl uence factors for the space structuring of the study area were given, and basic contents of the space structuring analyzed from fi ve perspectives of spatial structure, spatial form, ecological environment, integration of regional spaces, historical and cultural context, so as to explore ecological conservation and moderate utilization of the northern foot of the Qinling Mountains from the perspective of space structuring.

Fluid Activity and Tectonic Evolution in the Northern Qilian High-pressure Metamorphic Belt

The Northern Qilian high-pressure metamorphic belt has experienced multipledeformation-metamorphism, which consists of at least four stages. In 550.8-526 Ma, eclogites wereformed. High temperature and pressure caused the escape of a large quantity of gas-liquid fluidsfrom rocks while silicate melt was generated. In the late stage, small amounts of CO_2 and H_2Oinfiltrating along fractures were introduced. In the formation of glaucophane schist (447-362 Ma),devolatilization reactions were dominated during the subduction-uplift stage of the paleoplate. Inthe uplift-exhumation stage (400-380 Ma) the increase of internal space of fractures in the rocksfavoured fluid infiltration and concentration. These fluids participated in hydration reactions inthe retro-metamorphism. The fluids participating in the mineral reactions have the compositions ofCaCl_2-NaCl-H_2O. In subsequent thrusting (<380 Ma), the metamorphic terrain was uplifted to theshallower crust and ductile-shearing deformation took place, which caused mainly dehydrationreactions of minerals. In a near-surface environment the metamorphic terrain experienced brittledeformation, forming many accompanying fractures. Immiscible CO_2 and low-salinity aqueous fluidsoccurred in these secondary microfractures and were trapped and sealed. The thermodynamic conditionsof different deformation-metamorphic stages of the metamorphic terrain were calculated and thecorresponding P-T-t path was deduced, showing that the metamorphic terrain has experienced aclockwise path indicated by T- and P-rising, and T- and P-falling processes. This reveals that thesubduction zone has undergone multiple tectono-dynamic processes, i.e. initial deep burial,subsequent quick uplift and near-surface tectonism.

Geology,Geochemistry and Minerogenesis of the Shijuligou Zinc-Copper Deposit in Gansu,China

The Shijuligou deposit was separated by an arcuate ductile shear zone cross the center of the deposit region, resulting in the difference between the southern and northern ore bodies. The lead （Pb） isotopic data of ores of the Shijuligou copper deposit have averages of 206Pb/204pb, 207pb/204pb, and 20spb/204pb in 17.634, 15.444, and 37.312, respectively. It has been shown that ore-forming metals originated from intrusive and extrusive rocks in the upper part of ophiolites. The sulfur isotopic data of pyrite and chalcopyrite in the northern part change from ＋7.61‰ to ＋8.09‰ and ＋4.95‰ to ＋8.88‰ in the southern part. Isotopes of δ18O in the Shijuligou copper deposit are between ＋11.1‰ and ＋18.6‰, with the calculated δ18OH2O at ＋0.65‰. It is suggested that the mineralized fluid is a mixture of magma fluid, meteorological water, and seawater through circulating and leaching metals from the volcanic rocks. The zircon uranium-lead （U-Pb） dating of gabbro is 457.9_＋1.2 Ma, and the lower crossing age of the discordant and concordia curves of pyroxene spilite of zircon is 454_＋15 Ma. It is indicated that the Shijuligou deposit formed in a new ocean crust （ophiolite） of the back-arc basin in the late Ordovician. Mineralization should occur in the intermittence period after strong volcanic activity, and the age should be the late Ordovician. Moreover, the mineralization of ophiolite-hosted massive sulfide deposits in the ancient orogenic belt of the late Ordovician in the northern Qilian Mountains was controlled by the primary fault/fracture, with the forming of a metallogenic hydrothermal system by a mixture of volcanic magma fluid and seawater, which circularly leached the metallogenic metals from the volcanic rocks, resulting in their accumulation. The ore bodies were transformed with morphology and metallogenic elements. Jasperoid is an important sign for prospecting such deposits. There were many island arcs in the continent of China. This study provides evidence for understanding and exploration of ophiolite-hosted massive sulfide deposits in western China, especially in the area of northern Qilian Mountains.

Lower time limit on the UHPM rock exhumation: Discovery of eclogite pebbles in the Late Jurassic conglomerates from the northern foot of the Dabie Mountains, eastern China

Eclogite pebbles are first discovered in late Jurassic conglomerates of the Fenghuangtai Formation from the northern foot of the Dabie Mountains, eastern China. The eclogite shows relatively strong retrograde metamor-phism. The major remnant minerals are garnet, phengite, quartz, rutile, clinozoisite, fingerprint(or worm)-form sym-plectite and pseudomorphic enclosure of coesite in garnet. End-member components of the garnet mainly made up of grossular (27.7%-37.8%), almandinc (45.5%-49.0%) and pyrope (12.3%-25.7%). End-member components of the pyrope is less than 30%, i.e. equivalent to C type eclogite. Si-cations of the phengite are 3.44-3.54 p.f.u. (taking O=11as standard). It is estimated that the pressures are 2.5-3.2 GPa, the temperatures are 600-900℃. Discovery of the eclogite pebbles in the late Jurassic conglomerates from the northern foot of the Dabie Mountains suggests that the HP-UHP metamorphic rocks of the Dabie Mountains, which were formed in Triassic, had been exposed to the surface in

^(40)Ar/^(39)Ar isochron ages of lawsonite blueschists from Jiuquan in the northern Qilian Mountain,NW China,and their tectonic implications

Using laser 40Ar/39Ar dating method,we have gotten the metamorphic ages of lawsonite blueschist and epidote blueschist from Jiuquan,northern Qilian Mountain,NW China.The high quality laser 40Ar/39Ar dating of glaucophane from lawsonite blueschist gives an isochron age of 413±5 Ma.The isochron age obtained from phengite in epidote blueschist is 415±7 Ma.These data,combining with peak metamorphic P-T conditions and regional geological setting,allow us to infer that the lower limit of the ages of the prograde subduction metamorphism from lawsonite blueschist facies to epidote blueschist facies occurred at ca.413-415 Ma,which also suggests that the formation of lawsonite blueschist in the northern Qilian Mountain maybe resulted from the corner flow in the cold subduction zone.This study shows that the final closing time of the northern Qilian remnant oceanic basin is about 413-415 Ma,which also represents the convergent age between the North China Craton and the Qaidam block.

基于“两山”理论的秦岭北麓乡村空间营建策略研究

空间营建是秦岭北麓乡村地区“两山”实践的重要保障.研究提出在乡村“资源-资产-资本”的转化过程中,应构建“两环节、三层次、多主体”的“两山”转化空间营建路径:以生态基础培育和多元增值开发为两大空间营建环节,构建“区域→单元→地块”三层次营建体系,建立多主体参与共赢的营建机制.研究以西安鄠邑区为例,梳理其在大都市圈发展背景下“两山”转化的乡村空间营建问题,提出“要素统筹、生境修复、产居转型、有序共建”四方面空间营建策略,形成地域适宜性的绿色共建模式,以期为地区乡村振兴和高质量建设提供借鉴.

秦岭北麓乡村可持续发展的环境美学评价体系构建

构建秦岭北麓乡村的环境美学评价体系,旨在优化景观发展,通过视觉美感、自然环境、生态平衡、文化传承和居民满意度等多维度指标,采用定量与定性分析,为乡村规划提供科学支持,促进生态文明,推动区域可持续发展,并为相似乡村地区提供参考。

祁连山北麓荒漠草原5种优势植物生物量与土壤养分特征

为明晰荒漠草原优势植物的植物生物量与土壤养分关系,研究选取祁连山北麓肃北区域荒漠草原骆驼蓬(Peganum harmala)、狗尾草(Setaria viridis)、中华羊茅(Festuca sinensis)、碱茅(Pucci-nellia distans)和冰草(Agropyron cristatum)5种优势植物,测定该其生物量和根际土壤养分,探究其植物生物量分配及其与土壤养分间的关系。结果表明:(1)5种优势植物间总生物量和根冠比差异显著(P<0.05),骆驼蓬总生物量最高,碱茅最低。多年生的骆驼蓬、碱茅、中华羊茅和冰草植物生物量大部分集中在地下,一年生的狗尾草植物生物量大部分集中在地上,不同植物间根冠比大小为:碱茅>冰草>中华羊茅>骆驼蓬>狗尾草。(2)5种植物根际土壤有机碳、碱解氮、速效钾、全氮、全磷、全钾及其化学计量特征均存在显著差异(P<0.05),5种植物根际间土壤碳氮比大小为碱茅>狗尾草>冰草>骆驼蓬>中华羊茅。(3)不同植物生物量、根冠比及土壤养分变异性不一致,骆驼蓬、狗尾草和中华羊茅的根际土壤全钾与碱茅和冰草的根际土壤含水量等均为弱变异,而土壤养分及其化学计量特征为中等变异。5种优势植物的生物量与根际土壤碱解氮和全钾呈正相关性(P<0.05)。可见荒漠草原生态系统中植物生物量分配和根际土壤养分在生活史和物种间的差异较大,今后应根据不同优势植物养分需求,合理施肥来修复退化的荒漠生态系统。

祁连山北坡不同纬度青海云杉及林下土壤化学计量特征

深入探讨植物和土壤化学计量的空间格局和驱动因子,对于把握元素循环和量化生态系统对环境因子的响应具有重要意义。基于此,实验测定了祁连山北坡不同纬度青海云杉组织及土壤碳(C)氮(N)磷(P)含量,采用单因素方差分析(One-Way ANOVA)、皮尔逊相关分析(Pearson correlation)及冗余分析(Redundancy analysis,RDA)来揭示祁连山北坡不同纬度青海云杉及林下土壤化学计量特征及关键影响因素。结果表明:(1)青海云杉组织和土壤C、N含量随纬度增加而减少;而青海云杉组织N∶P、C∶P随纬度增加而增大,土壤N∶P、C∶P则减小。(2)青海云杉组织养分分配不均衡,C、N元素含量,叶>枝>根,而P元素含量,枝>叶>根,且青海云杉枝、根N∶P均小于14,表明祁连山青海云杉生长受土壤N元素的限制。(3)土壤因子(含水量、pH值、容重、SOC、TN、TP及SOC∶TN∶TP)及气候因子(年均气温和年均降水量)变化影响青海云杉组织N、P元素含量,且土壤因子对植物组织N、P、N∶P的解释率大于气候因子,其中,植物叶片N、N∶P与土壤TN、TN∶TP呈正相关(P<0.05),而植物根系N、N∶P值与气温呈负相关、与年均降水量呈显著正相关(P<0.05)。本研究有助于评估祁连山青海云杉生态系统养分动态变化,探索不同纬度青海云杉林养分调控分配机理,以期为祁连山森林生态系统的持续健康发展提供科学依据。

基于AHP-EWM-TOPSIS的秦岭北麓西安段冰酒葡萄生态适宜性评价

本研究旨在评估冰酒葡萄(Ice wine grape)在秦岭北麓西安段的生态适宜性,以促进该作物种植的经济潜力并优化当地葡萄产业结构。根据冰酒葡萄生长需求和秦岭北麓自然气候特点,研究选取最冷月均温、≥10℃有效积温、生长季干燥度、坡度、土壤pH等评价因子,确立冰酒葡萄适宜性评价体系。基于秦岭北麓西安段2000—2021年逐日气象观测数据、生态数据,采用层次分析法(AHP)、改进熵值法(EWM)、TOPSIS综合评价法,本研究构建了一个冰酒葡萄种植综合区划评估模型,对影响冰酒葡萄种植的气候、地形、土壤三大指标的空间分布进行分析。经统计分析得出最适宜区、适宜区、次适宜区和不适宜区4个等级。结果表明,所提出的方法能够有效地识别秦岭北麓西安段内冰酒葡萄种植的生态优势区域,且所得区划结果与实际情况高度一致。这一发现对冰酒葡萄种植的区域布局和科学规划提供了重要参考。

秦岭北麓筠竹种子育苗试验

因气候条件的限制,秦岭北麓很难获得竹子种子,因而难以通过播种育苗获得造林绿化所需要的大量苗木。2019年7月在秦岭北麓陕西省楼观台国有生态实验林场辖区的森林公园内发现了一株筠竹开花并结实,遂采集种子,开展了播种试验,以期探讨秦岭北麓竹种子育苗的可行性。结果显示,筠竹采种后在室温下贮藏,第2年播种的出苗率为25.4%;实生苗前3年的生长状况优于秦岭北麓优势竹种淡竹的生长。该研究表明,在秦岭北麓筠竹通过播种进行繁殖是可行的,并探索了一套实生苗繁育的管理经验,可在一定范围内推广,为绿化造林和生态建设提供大量苗木。

秦岭北麓西安段峪口村落洪涝适应性营建智慧研究

秦岭北麓西安段为洪涝灾害多发区域.在长期同雨洪博弈共生的过程中,当地传统村落形成了以低技术、低成本、低维护为特征的洪涝适应性智慧.在洪涝风险日益增多的当下,这些传统实践智慧对促进区域人水和谐、洪涝韧性和可持续发展具有重要借鉴意义.以秦岭北麓典型区域内峪口传统村落为例,基于田野调查、多源数据比对互证法和图解分析法,本文旨在阐明洪涝适应与村落营建关系的基础上,在选址、街巷布局及洪涝管控设施系统等三个方面,系统研究其洪涝适应性营建智慧,以期在新时期为城乡洪涝韧性人居环境规划营建,提供理论和经验借鉴.

北祁连山西段金属矿床时空分布和生成演化

北祁连山西段以产镜铁山式铁矿而著称,近几年找金和找铜又有新突破。本文从地质构造历史演化角度探讨了区内金属矿床分布的规律。提出从古元古代到印支期已经历了9期成矿作用,迄今划分出四个矿床成矿系列及两个矿床成矿亚系列。区内铁呈现出多期成矿,而大多数金属在加里东期“爆炸式”堆积,金的富集成矿与大型剪切—走滑、深部流体上升卸载有关。

柴达木盆地北缘新元古代蛇绿岩的厘定——罗迪尼亚大陆裂解的证据?

柴达木盆地北缘鱼卡河及绿梁山一带“奥陶纪”滩涧山群中分出一套“新元古代”的蛇绿岩组合,主要由玄武质(枕状)熔岩、岩墙群、辉长岩等古洋壳岩石组成,其中以MORB和岛弧玄武岩为主,岩石变质程度达角闪岩相。蛇绿岩洋壳的Rb-Sr同位素等时线年龄值为768Ma±39Ma,Sm-Nd同位素等时线年龄值780Ma±22Ma。这套古洋壳岩石与典型的奥陶纪(约500Ma)火山岩不同,后者主要为中基性岛弧火山岩,岩石仅发生轻微绿片岩相变质;而前者与榴辉岩的成分可以对比,并且与榴辉岩原岩的时代(750～800Ma)相同。推断绿梁山的海底玄武质岩类可能就是榴辉岩的原岩,祁连地区新元古代蛇绿岩洋盆是在罗迪尼亚大陆大约800～750Ma发生裂解的基础上形成的。

祁连山(北坡)水热状况与植被垂直分布

分析了祁连山北坡水热状况与植物垂直分布的关系 ,结果表明其气候在水平、垂直方向都有明显的差异 ,气温随海拔升高而递减 ,递减率为 0 .5 8℃ / hm;降水量随海拔升高而递增 ,递增率为 1 8.6 mm/ hm。从而使区内植被分布具有明显的垂直梯度变化规律 ,从下到上依次为荒漠草原植被带、干性灌丛草原植被带、山地森林草原植被带、亚高山灌丛草甸植被带、高山寒漠草甸植被带 ,其中山地森林草原植被带是主要的植被分布带 ,与上下限的灌丛构成祁连山水源涵养林生态系统 ,成为祁连山山地生态系统的主体。

北祁连山奥陶纪弧后盆地火山岩浆成因

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