Temporal and spatial responses of ecological resilience to climate change and human activities in the economic belt on the northern slope of the Tianshan Mountains, China

In the Anthropocene era,human activities have become increasingly complex and diversified.The natural ecosystems need higher ecological resilience to ensure regional sustainable development due to rapid urbanization and industrialization as well as other intensified human activities,especially in arid and semi-arid areas.In the study,we chose the economic belt on the northern slope of the Tianshan Mountains(EBNSTM)in Xinjiang Uygur Autonomous Region of China as a case study.By collecting geographic data and statistical data from 2010 and 2020,we constructed an ecological resilience assessment model based on the ecosystem habitat quality(EHQ),ecosystem landscape stability(ELS),and ecosystem service value(ESV).Further,we analyzed the temporal and spatial variation characteristics of ecological resilience in the EBNSTM from 2010 to 2020 by spatial autocorrelation analysis,and explored its responses to climate change and human activities using the geographically weighted regression(GWR)model.The results showed that the ecological resilience of the EBNSTM was at a low level and increased from 0.2732 to 0.2773 during 2010–2020.The spatial autocorrelation analysis of ecological resilience exhibited a spatial heterogeneity characteristic of"high in the western region and low in the eastern region",and the spatial clustering trend was enhanced during the study period.Desert,Gobi and rapidly urbanized areas showed low level of ecological resilience,and oasis and mountain areas exhibited high level of ecological resilience.Climate factors had an important impact on ecological resilience.Specifically,average annual temperature and annual precipitation were the key climate factors that improved ecological resilience,while average annual evapotranspiration was the main factor that blocked ecological resilience.Among the human activity factors,the distance from the main road showed a negative correlation with ecological resilience.Both night light index and PM2.5 concentration were negatively correlated with ecological resilience in the areas with better ecological conditions,whereas in the areas with poorer ecological conditions,the correlations were positive.The research findings could provide a scientific reference for protecting the ecological environment and promoting the harmony and stability of the human-land relationship in arid and semi-arid areas.

Response of ecosystem service value to land use/cover change in the northern slope economic belt of the Tianshan Mountains, Xinjiang, China

Land use/cover change(LUCC)is becoming more and more frequent and extensive as a result of human activities,and is expected to have a major impact on human welfare by altering ecosystem service value(ESV).In this study,we utilized remote sensing images and statistical data to explore the spatial-temporal changes of land use/cover types and ESV in the northern slope economic belt of the Tianshan Mountains in Xinjiang Uygur Autonomous Region,China from 1975 to 2018.During the study period,LUCC in the study region varied significantly.Except grassland and unused land,all the other land use/cover types(cultivated land,forestland,waterbody,and construction land)increased in areas.From 1975 to 2018,the spatial-temporal variations in ESV were also pronounced.The total ESV decreased by 4.00×10^(8) CNY,which was primarily due to the reductions in the areas of grassland and unused land.Waterbody had a much higher ESV than the other land use/cover types.Ultimately,understanding the impact of LUCC on ESV and the interactions among ESV of different land use/cover types will help improve existing land use policies and provide scientific basis for developing new conservation strategies for ecologically fragile areas.

Evolution of economic linkage network of the cities and counties on the northern slope of the Tianshan Mountains,China

The exchanges between cities and counties in the northern slope economic belt of Tianshan Mountains(NSEBTM)are increasingly frequent and the economic linkages are increasingly close,but the spatial distribution of economic development and linkages among the cities and counties within NSEBTM is uneven.Therefore,it is of great significance to study the evolution of spatial-temporal pattern of the economic linkage network of cities and counties on NSEBTM to promote the coordinated and integrated development of the regional economy on NSEBTM.In this study,we used the modified gravity model and social network analysis method to analyze the spatio-temporal evolution characteristics of the economic linkage network structure of cities and counties on NSEBTM in 2000,2010,and 2020.The results showed that the comprehensive development quality level of cities and counties on NSEBTM increased from 2000 to 2020,its growth rate also increased,and its gap between cities and counties continued expanding.Both the spatial distribution patterns of the comprehensive development quality level of cities and counties on NSEBTM in 2000 and 2010 were presented as“high in the middle and low at both ends”,while the spatial distribution pattern of 2020 was exhibited as“high value and low value staggered”.The total amount of external economic linkages of cities and counties on NSEBTM showed an obvious upward trend,and its gap between cities and counties continued expanding,presenting a pattern of“a strong middle section and weak ends”.The direction of economic linkages of NSEBTM existed obvious central orientation and geographical proximity.The density of economic linkage network of NSEBTM increased from 2000 to 2020,and the structure of economic linkage network changed from single-core structure centered with Urumqi City to multicore structure centered with Urumqi City,Karamay City,Shihezi City,and Changji City,shifting from unbalanced development to balanced development.In the future,we should accelerate the construction of urban agglomeration on NSEBTM,cultivate a modern Urumqi metropolitan area,improve comprehensive development quality of the cities and counties at the eastern and western ends,strengthen the intensity of economic linkages between cities and counties,optimize the economic linkage network,and promote the coordinated and integrated development of regional economy.

Geochemical Characteristics of Granitoids in the Eastern Sector of the Northern Tianshan Mountains in Xinjiang

The granitioids in question are located in the geosynclinal fold belt of the Northern Tianshan Mountains.The magmas are intruded into a Carboniferous marine volcanic-sedimentary rock series. forming a contempo-raneous. intermediate-basic to acid. composite intrusion. With a whole-rock Rb-Sr isochron age of 315.7 Ma. itis considered to be of middle Heicynian age. The granitoids have a SiO_2 content of 48-78%, a calc-alkali indexof 60 and silica-alkali indices ρ=2.2-2.4 and σ=1.5-2. From basic to acid compositions, the total REE con-tent increases from 38 to 143 ppm. δEu ranges from 0.47 to 0.86 and the Eu anomalies are negative. Thenormalized curves of REE of various rock types are very similar. These coupled with the characteristics of traceelement geochemistry show that the intrusion is an island arc-continental margin, calc-alkaline one. Theδ^(18)O values range from 5.8 to 8.9‰ and the ^(87)Sr/^(86)Sr initial ratio is 0.705. The materials of the intrusion arecomposed of a mixture of the magmas at the top of the upper mantle and in the lower crust, This indicates thatthe rocks might be consanguineous. differentiated and evolved products and possess the characteristics of Ⅰtype granites.

Late Permian to Triassic intraplate orogeny of the southern Tianshan and adjacent regions, NW China

The South Tianshan Orogen and adjacent regions of Central Asia are located in the southwestern part of the Central Asian Orogenic Belt. The formation of South Tianshan Orogen was a diachronous, scissors-like process, which took place during the Palaeozoic, and its western segment was accepted as a site of the final collision between the Tarim Craton and the North Asian continent, which occurred in the late Palaeozoic. However, the post-collisional tectonic evolution of the South Tianshan Orogen and adjacent regions remains debatable. Based on previous studies and recent geochronogical data, we suggest that the final collision between the Tarim Craton and the North Asian continent occurred during the late Carboniferous. Therefore, the Permian was a period of intracontinental environment in the southern Tianshan and adjacent regions. We propose that an earlier, small-scale intraplate orogenic stage occurred in late Permian to Triassic time, which was the first intraplate process in the South Tianshan Orogen and adjacent regions. The later large- scale and well-known Neogene to Quaternary intraplate orogeny was induced by the collision between the India subcontinent and the Eurasian plate. The paper presents a new evolutionary model for the South Tianshan Orogen and adjacent regions, which includes seven stages： （I） late Ordovician-early Silurian opening of the South Tianshan Ocean; （11） middle Silurian-middle Devonian subduction of the South Tianshan Ocean beneath an active margin of the North Asian continent; （111） late Devonian-late Carboniferous closure of the South Tianshan Ocean and collision between the Kazakhstan-Yili and Tarirn continental blocks; （IV） early Permian post-collisional magmatism and rifting; （V） late Permian-Triassic the first intraplate orogeny; （Vt） Jurassic-Palaeogene tectonic stagnation and （VII） Neocene-Quaternary intraplate orogeny.

天山北坡前山带12种植物对干旱胁迫和复水的生理响应及抗旱性评价

【目的】前山带是天山北坡山地-绿洲-荒漠生态系统的重要组成部分,探讨植物对干旱胁迫的动态生理适应性和抗旱性评价方法,筛选植被恢复的适宜树种,对该区域植被生态恢复具有重要意义。【方法】以新疆天山北坡前山带种植的12种植物为研究对象,观测灌水后土壤水分时空变化,分析干旱和复水对植物光合和抗逆生理指标的影响,采用主成分分析评价12种植物的抗旱能力。【结果】(1)干旱胁迫后,土壤水分散失在0-20 cm层最快,20-40 cm层次之,40-60 cm层最慢,不同植物采用不同策略改变生长情况来适应干旱;(2)干旱胁迫后,叶片净光合速率(P_(n))、气孔导度(G_(s))、蒸腾速率(T_(r))、胞间CO_(2)浓度(C_(i))、PSⅡ潜在活性(F_(v)/F_(o))、PSⅡ最大光化学效率(F_(v)/F_(m))、电子传递速率(ETR)和叶绿素含量降低,而抗逆生理指标超氧化物歧化酶(SOD)活性、脯氨酸含量、丙二醛(MDA)含量及非光化学淬灭系数(qN)升高,复水后各指标都有一定程度的恢复,但均未达到初始水平;(3)主成分分析结果显示,Pn、叶绿素含量、ETR和MDA含量等指标贡献率较大,梭梭、柽柳、刺蔷薇和柠条锦鸡儿抗旱性较强,‘中亚沙棘’、‘新棘5号’、‘新棘1号’和山杏次之,而‘新棘4号’、‘新棘3号’、文冠果和‘新棘2号’较弱。【结论】Pn、叶绿素含量、ETR和MDA含量可作为评价植物适应干旱的重要指标;新疆天山北坡前山带植被生态恢复应优先选择梭梭、柽柳、刺蔷薇及柠条锦鸡儿进行建植。

天山北坡经济带城乡聚落格局变化与影响因素分析

以天山北坡经济带城乡聚落为研究对象,采用景观格局指数、地理信息系统(GIS)空间分析、位序-规模法等分析1980-2020年间城乡聚落格局的变化,结合地理探测器从自然、区位及社会经济因素探究城乡聚落格局的影响因素。结果表明:1980-2020年间,城乡聚落数量、规模持续扩张且趋于集聚,前20 a扩张以耕地、草地为主,后20 a以未利用地为主;城乡聚落密度变化显著,高密度区主要集中在各绿洲呈现“多核集中分布”特征,中密度区沿高密度区周围扩张,低密度区沿绿洲边缘分布并在非绿洲区有扩张;首位聚落规模发展较好,趋于位序-规模曲线,中型聚落略微发育,小型聚落数量持续减少;交通等区位因素是天山北坡城乡聚落格局的首位影响因素,社会经济因素次之,自然地理因素影响较小,各影响因素差异显著。

近60a天山北坡经济带天然径流量时空变化及归因识别

天山北坡经济带地处干旱的亚洲腹地,厘清天然径流量(NR)时空变化及成因对统筹区域发展、维持生态安全至关重要。为此,采用Sen’s斜率估计法、Mann-Kendall趋势检验等分析径流量时空变化,基于Budyko假设的水热耦合平衡方程定量评价降水、潜在蒸散发及下垫面对NR变化的贡献。结果表明:(1)近60a天山北坡经济带NR总体呈显著增加趋势,年变化率0.68mm·a-1。1961—1986年波动较大,1987—2012年波动变小且NR增加明显,2013年后NR显著减少。(2)NR大小与海拔变化在空间上高度叠合,天山北坡经济带西部和南部NR较大,西南部与西北部增长幅度大。(3)NR突变点为1980年与2013年,降水一直是NR变化的主导因素,但下垫面影响不断加大,近60a贡献率从31.5%增至45.5%。(4)2012年前天然径流量主要受降水主导,但不同区域影响不同。2013年,西部、东部与中南部下垫面对径流量的影响已超过降水成为主导因素。研究成果深化了天山北坡经济带NR变化的认识,为天山北坡经济带高质量发展提供科学支撑。

数字经济与实体经济耦合协调研究——基于天山北坡经济带的实证研究

数字经济与实体经济之间有着紧密的联系。通过对天山北坡经济带2016-2020年9个县市的面板数据进行统计分析,构建了数字经济和实体经济评价的基本框架,并通过耦合模型评价了二者的耦合协调程度。结果表明:2016-2020年,天山北坡经济带数字经济与实体经济发展耦合协调度总体呈上升趋势,除奎屯市以外,其他各县市都达到了失调以上;乌鲁木齐市发展一直很稳定,并且耦合协调度在一直上升。但由于各个县市之间仍存在着较大差距,所以总体的耦合协调度水平还不够高。因此,需要积极促进居民消费,大力发展工业;继续加强薄弱部门的基础设施建设;推动中小企业数字化转型。通过这些措施促进区域经济社会协调发展。

天山北坡前山带疏花蔷薇集水造林技术措施筛选

【目的】研究不同整地方式和保水保墒措施对疏花蔷薇造林成活率、生长量及生理生化指标的影响,筛选出在天山北坡前山带区域疏花蔷薇造林最佳的综合技术措施。【方法】在水平沟、V形坑两种整地方式下,设置覆膜(A)、膨润土保水(B)、黄腐酸保墒(C)3种单项保水保墒措施以及A+B、A+C、B+C、A+B+C四种综合保水保墒措施,对照为无保水保墒措施,分析不同造林技术措施对造林地土壤含水量的影响以及疏花蔷薇生长指标、生理指标、光合特性对其响应。【结果】相同保水处理水平沟疏花蔷薇生长量、成活率与V形坑无显著差异(P>0.05),土壤含水量、光和指标、生理指标较优于V形坑;不同保水处理疏花蔷薇土壤含水量、光合特性、生理特性、生长量和存活率存在显著差异(P<0.05),均以A+B+C处理最佳,两项措施以A+B处理最优,单项措施A处理最优;通过隶属函数值法综合评价各造林技术抗旱性,水平沟A+B+C处理得分最高,V形坑CK处理得分最低。【结论】干旱、半干旱地区造林成活率在70%(含)以上为合格,选出疏花蔷薇最佳造林技术为V形坑A+B处理、V形坑A处理。

天山北坡前山带典型灌木光合特性对干旱胁迫的响应

【目的】研究干旱胁迫对天山北坡前山带区域典型灌木植物光合特性的影响。【方法】以天山北坡前山带典型灌木(锦鸡儿Caragana sinica Rehd.、沙棘Hippophae rhamnoides L.、刺蔷薇Rosa acicularis Lindl.和文冠果Xanthoceras sorbifolium Bunge.)为研究对象,人为控制土壤水分补给,利用Li-6400便携式光合测定仪监测叶片光合生理指标及水分利用效率(WUE),研究4种灌木光合特性与水分利用效率在不同土壤体积含水量下的变化特征,分析4种灌木在不同干旱程度下的响应机制。【结果】4种灌木叶片净光合速率(Pn)、气孔导度(Gs)、胞间CO_(2)浓度(Ci)和蒸腾速率(Tr)均表现为随干旱程度的加剧而降低,锦鸡儿、沙棘、刺蔷薇和文冠果光合速率明显被抑制的土壤含水量临界值分别是10.08%、12.59%、9.85%、10.59%,土壤含水量极限值分别是7.76%、9.19%、7.52%、8.17%。锦鸡儿和沙棘的WUE均是在轻度干旱程度时达最大值,而刺蔷薇和文冠果则是在中度干旱程度达最大值,并且锦鸡儿、沙棘、刺蔷薇和文冠果在土壤含水量分别达到11.60%、12.25%、8.75%、12.00%时具有最优WUE;灌木叶片WUE与空气温度呈极显著正相关关系(P<0.01),与光合有效辐射呈显著正相关关系(P<0.05),而与Pn、Tr、Gs和Ci相关性较弱。【结论】当土壤含水量低于9.85%时,4种灌木植物光合特性明显被抑制,但土壤含水量达到8.75%~12.25%,植物对土壤水分利用效率达到最优,4种灌木抗旱性为刺蔷薇>锦鸡儿>文冠果>沙棘。适当补水对灌木植物抗逆性维持具有重要作用。

天山北麓前山带对平原区水文过程的影响

借助地理信息系统与遥感图像处理技术 ,分析了天山北麓前山带对平原区水文过程的影响 ,结果表明 :阻碍地下水的流动使其转化为地表水从而增加了河川径流流量 ;增大了河川径流的年调节能力 ,使绿洲可以稳定地发展 ;阻止山区洪水与泥石流对绿洲的危害 ;影响到山前潜水埋藏深度、潜水溢出带分布与溢出量变化。对山区生态环境有一定的保护作用 ;

塔里木盆地北缘—南天山造山带盆-山耦合和构造转换

文章探讨了塔里木盆地北缘和南天山造山带的盆-山耦合和构造转换过程。塔里木盆地属于典型的叠合盆地,经历了多期构造演化。研究表明,在地史时期中,塔里木盆地北缘和相邻南天山造山带经历了多期和复杂的盆山耦合和盆山转换过程,形成多种类型盆山耦合和转换方式。(1)按时间域可划分为:早古生代陆内裂陷盆地-早期伸展造山-晚期挤压造山耦合,晚古生代陆内裂陷盆地-弧后造山-晚期碰撞造山耦合,中生代陆内前陆盆地-挤压造山耦合,古近纪前陆盆地-挤压造山耦合,新近纪—第四纪再旋回前陆盆地-挤压造山耦合;(2)按深度域可划分为:深部地幔俯冲型盆-山耦合,地壳分层滑脱拆离型盆-山耦合,基底滑脱拆离型盆-山耦合,古生代伸展和逆冲推覆型盆-山耦合,中—新生代逆冲推覆型盆-山耦合;(3)按运动学和动力学可划分为:逆冲推覆型盆-山耦合和接触关系、重力滑脱型盆-山耦合和接触关系、走滑转换型盆山耦合和接触关系、深部岩浆上涌焊接型盆-山耦合和接触关系、鳄鱼嘴型盆-山耦合和接触关系。

新疆石河子南山地区表土花粉研究

天山作为亚洲大陆最大的山系之一,横贯于新疆的中部,成为分隔南、北疆自然地理区系的山系,它对花粉的传播、保存、搬运与沉积具有重大作用。根据对西北干旱区域新疆石河子南山地区一条沿着海拔高度从2400 m到300 m的样带所采集的23个表土花粉样品的孢粉组合图式和现代植被样方调查资料,探讨了北坡垂直带的植被与表土花粉之间的关系。该区表土孢粉谱可分为4个孢粉组合带,分别对应森林植被带、森林草原植被带、蒿属荒漠带和典型荒漠带。比较特殊的是典型荒漠带被划分为两个亚带,一个亚带是以蒿属、藜科占主要成分的典型荒漠带,另一亚带蒿属、藜科含量较高并含有大量沼泽蕨和芦苇植硅体,兼具典型荒漠和湿地特征。在海拔400 m以上,孢粉组合与现代植被的对应关系较好,带Ⅰ中较高含量的云杉花粉验证了以云杉为主的森林植被带。带Ⅱ中以云杉为主的乔木植物和含量较高的藜科、蒿属和蓼属等草本植物为主的孢粉组合特征与森林-草原植被带的植被特征较为类似。云杉属花粉在海拔低于1350 m的地方即林带下方所占的比例很小,一方面由于距林地的距离较远,另一方面,可能是山风气流对云杉花粉往下搬运的能力较弱所致。带Ⅲ的蒿属花粉含量较高,与该带植被中绢蒿较多有一定的关系,带Ⅳ以藜科为主的花粉组合特征代表了这个植被带的荒漠植被类型。但是在海拔400 m之下,带Ⅳ的亚带Ⅳ2的高含量的沼泽蕨和芦苇植硅体的孢粉组合在一定程度上还代表了古湿地环境。通过该部分表土花粉组合特征与草滩湖剖面孢粉谱的对比,验证了当地农业种植选址的生态可行性,同时就开垦程度对环境的影响进行了初步探讨。另外,亚带Ⅳ2的蒿属/藜科(Artemisia/Chenopodiaceae(A/C))比值比亚带Ⅳ1高,可能与该样点受人为扰动较大有关。

天山山区近40年秋季气候变化特征与南、北疆比较

利用新疆1959～1998年的秋季温度降水资料,分析天山山区近40年来秋季气候变化的基本特征,所得结果如下:(1)天山山区秋季温度在冷暖变化阶段上与北疆的相似性强于南疆,但其秋季降水在干湿变化阶段上与南、北疆不同。(2)秋季温度空间分布的同步变化性以北疆为最好,南疆最差,天山山区居中。秋季降水空间分布的同步变化性以南疆最好,天山山区最差,北疆居中。(3)20世纪60～90年代,天山山区表现为波动升温,而南疆和北疆表现为持续增温,均以90年代温度最高,80年代是三大区域秋季降水最多的年代。60,70及90年代,三大区域的秋季降水均低于30年均值。

新疆中天山干沟一带蛇绿混杂岩和志留纪前陆盆地的发现及其意义

托克逊县干沟一带出露有早古生代蛇绿混杂岩和志留纪前陆盆地沉积。其时空配置表明,新疆中天山北缘早古生代大洋在奥陶纪曾发生大规模的向北消减,志留纪因前陆和岛弧的碰撞而形成前陆盆地,充填序列揭示了碰撞造山作用过程。对碎屑岩中陆源锆石同位素测年表明其最新物源的年龄不小于461Ma。而侵入该前陆盆地碎屑岩的花岗闪长岩中火成锆石的同位素测年数据为(386.1±4.1)Ma,限定了前陆盆地的上限。前陆盆地的终结标志着碰撞造山作用的结束。

天山山区与南、北疆近40a来的年温度变化特征比较研究

分析天山山区近40a来年温度变化的基本特征,并与南疆、北疆进行比较,其结果是:(1)天山山区年平均温度在冷暖变化阶段上与北疆的相似性强于南疆。(2)新疆三大区域年平均温度的最主要空间分布特征均是同步变化,但同步性的程度北疆较好,南疆及天山山区较差;而空间分布的反向变化性,南疆及天山山区较好,北疆较差。(3)三大区域年平均温度的年代际变化趋势是不同的,但均以20世纪90年代为最暖。(4)近40a的显著线性增温趋势以年平均最低温度及年平均温度表现得空间范围最广,年平均最高温度最差;年平均温度的长期增温率以北疆最大,天山山区和南疆较小;年平均最低温度的10a增温率变化在0 34～0 37℃之间。(5)三大区域最佳升温趋势出现的时段比较一致,增温率以北疆为最大,天山山区和南疆相同。(6)北疆与南疆年平均温度分别在1960年和1978年发生了由低向高的突变。

天山北麓经济发展与绿洲扩张

借助地学信息图谱技术,以不同时相、不同尺度的图像数据源为基础,编制出1949年以来天山北麓绿洲分布图4幅。绿洲演化规律为:1949～1967年为绿洲迅速扩张阶段,耕地面积急剧增加;1967～2000年绿洲扩张速度减缓,耕地面积总量基本保持平衡,城市化进程加快。分析了天山北麓绿洲经济带发展现状,论述了北麓经济带、城市群和主导产业分布格局,讨论了绿洲扩张过程中水资源利用变化以及生态环境问题。这些对研究50年来北麓绿洲经济带的变化具有重要意义,也对未来北麓绿洲经济带的发展具有指导作用。

天山山区近40a夏季降水变化及与南北疆的比较

利用新疆 195 9— 1998年的降水资料 ,分析了天山山区近 4 0a来夏季降水变化特征 ,并与南疆、北疆进行了比较 .结果表明 :天山山区近 4 0a来的夏季降水在干湿阶段、最干最湿年份、降水变化的周期方面均与南北疆有别 ;天山山区夏季降水空间上的同步性变化比南疆及北疆弱一些 ;天山山区近 4 0a来夏季降水年代际变化与北疆较为相近 .新疆近 4 0a来夏季降水最多的年代是 90年代 ,天山山区偏多 12 % ,南疆偏多 2 5 % ,北疆偏多 2 1% .

天山山区与南北疆夏季温度变化对比分析

利用新疆1959～2000年夏季温度资料,采用滑动平均、最大熵谱、经验正交、线性回归方法,分析天山山区近42年来夏季温度变化的基本特征,并与南疆、北疆进行比较。结果表明:①天山山区在夏季温度的冷暖变化阶段以及最炎热、最凉爽年出现的年份与南疆和北疆不同;②夏季温度空间分布的同向性变化北疆最大,天山山区居中,南疆最小;夏季温度空间反向变化南疆和天山山区较大,北疆较小;③夏季温度的年代际变化趋势不同,天山山区持续增温,北疆波动增温,南疆变化稳定;④三种夏季增温的覆盖范围以最低温度为最广,其增温率天山山区最大,南疆最小,北疆居中。