Megafossils of Betulaceae from the Oligocene of Qaidam Basin and their paleoenvironmental and phytogeographic implications

Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant fossils.The Qaidam Basin has long been regarded as an ideal‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan Plateau.However,fossil angiosperms from the Qaidam Basin are rare,and our knowledge of its paleovegetation is poor.Here,we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin(Huatugou area).Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus grandis.These findings,together with other reported fossil plants from the same locality,reveal a close floristic linkage between the Qaidam Basin and Europe during the Oligocene.The northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late Paleogene.This floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies,which transported moisture and provided favorable climatic conditions.Indeed,fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene.

MC-ICP-MS 测定岩石标准物质的钒同位素组成

随着分析方法的发展和分析精度的提升,钒同位素已经越来越多地被用于各种地质过程研究。为了确保钒同位素分析测试过程中,可以有效地监控数据的准确度和精度,方便国际各实验室之间的数据对比,同时考虑到早期国际上常用美国地质调查局(USGS)的标准物质面临着库存不足等问题,本文采用多接收电感耦合等离子体质谱仪(MC-ICP-MS)测定了一系列国际地质标准物质和国家地质标准物质的钒同位素组成,δ51V值的测试精度优于0.08‰。本文选取的标准物质主要来自日本地质调查局(GSJ)和中国地质科学院地球物理地球化学勘查研究所(IGGE),包括一个安山岩(JA-1),三个玄武岩(JB-3、JB-1b和GBW07105),一个辉长岩(JGb-1),一个辉绿岩(GBW07123)以及一个土壤(GBW07454),钒含量范围为77~635μg/g,涵盖了目前大部分火成岩和部分土壤等天然样品含量的范围。这些标准物质除了土壤GBW07454,其他标准物质的钒同位素组成未曾被报道。经测量表明,辉长岩标准物质JGb-1具有最高δ51V值,为−1.05‰±0.08‰,安山岩标准物质JA-1具有最低δ51V值,为−0.34‰±0.06‰,其余标准物质的δ51V值变化范围为−0.72‰~−0.81‰,均落在MORB范围内。本文对这些标准物质钒同位素组成的报道,丰富了钒同位素研究的标准物质数据库,有助于未来在更多领域开展钒同位素研究。

Geochemical characteristics of the Xuanwei Formation in West Guizhou:Significance of sedimentary environment and mineralization

The Upper Permian Xuanwei Formation widely occurs in western Guizhou,unconformably overlying the Emeishan basalts,and mainly consists of black shales.It is～170 m thick at Cuyudong Village,Weining County,West Guizhou,China,where the samples of black shale and sandy shale were collected and analyzed.The shales mainly contain SiO2,18.9%?44.1%,Al2O3,14.8%?52.8%,Fe2O3,1.0%?41.2%,LOI,3.2%?21.1%,TiO2,1.0%-6.7%,and MgO,0.2%?2.5%.The contents of all other major elements are lower than 1.0%.It is shown that the black shales have higher contents of Fe2O3 and LOI than normal shales.The siderites occurred in the black shales with higher contents of Fe2O3,which may be attributed to hydrothermal activities on seafloor.All analyzed shale samples have extremely high Ga,47.8×10-6-109.9×10-6(70.5×10-6 on average),higher than the industrial mining standard of Ga Resource Industry Standard.The total contents of rare-earth elements(REE) of 9 black shale samples vary from 213×10-6 to 1460×10-6,suggesting that these black shales are enriched in REE.The shale-normalized REE patterns display both positive and negative Ce anomalies(Ce/Ce* from 0.5 to 1.7),revealing that the Xuanwei shales were precipitated under oxic and anoxic conditions.The Rb-Sr chronological diagram of 6 shale samples in the Xuanwei Formation shows an age of 255±12 Ma.Strontium isotopic ratios(87Sr/86Sr)t0 range from 0.70635 to 0.70711,suggesting that these Xuanwei black shales might be derived from chemical weathering of the Emeishan basalts.

Sources of organic matter and paleo-environmental implications inferred from carbon isotope compositions of lacustrine sediments at Inexpressible Island, Ross Sea, Antarctica

The carbon isotopic composition of organic matter （δ^13Corg） was determined in two sediment cores （IIL1 and IIL9） recovered from Inexpressible Island, Ross Sea, Antarctica, and analyzed to identify the sources of that organic matter. The δ^13Corg values of sediments of IIL9 were found to vary between -14.6‰ and -11.6‰, with a mean of-13.4‰ （n=48）. These values were significantly higher than those of IIL1 sediments which varied between -23.2‰ and -20.4‰, with a mean of-21.8%o （n=55）. The variation in δ^13Corg values in these two sediment cores indicate different sources of organic matter, The relatively high 6~3Corg values in IIL9 are in accordance with a source from algae, while the low δ^13Corg values in IIL1 evince significant influence from penguin guano with algae as the secondary source. Compared with the reference data from other high-latitude lake sediments and plants, the δ^13Corg values in IIL9 were extremely high, a result likely related to intense competition for CO2 assimilation among algal species during the growing season in this relatively shallow pond. These results indicate that sedimentary δ^13Corg is a reliable proxy for paleo-primary productivity in ponds at Inexpressible Island.

LncRNA GACAT2 binds with protein PKM1/2 to regulate cell mitochondrial function and cementogenesis in an inflammatory environment

Periodontal ligament stem cells(PDLSCs) are a key cell type for restoring/regenerating lost/damaged periodontal tissues, including alveolar bone, periodontal ligament and root cementum, the latter of which is important for regaining tooth function. However,PDLSCs residing in an inflammatory environment generally exhibit compromised functions, as demonstrated by an impaired ability to differentiate into cementoblasts, which are responsible for regrowing the cementum. This study investigated the role of mitochondrial function and downstream long noncoding RNAs(lnc RNAs) in regulating inflammation-induced changes in the cementogenesis of PDLSCs. We found that the inflammatory cytokine-induced impairment of the cementogenesis of PDLSCs was closely correlated with their mitochondrial function, and lnc RNA microarray analysis and gain/loss-of-function studies identified GACAT2 as a regulator of the cellular events involved in inflammation-mediated mitochondrial function and cementogenesis.Subsequently, a comprehensive identification of RNA-binding proteins by mass spectrometry(Ch IRP-MS) and parallel reaction monitoring(PRM) assays revealed that GACAT2 could directly bind to pyruvate kinase M1/2(PKM1/2), a protein correlated with mitochondrial function. Further functional studies demonstrated that GACAT2 overexpression increased the cellular protein expression of PKM1/2, the PKM2 tetramer and phosphorylated PKM2, which led to enhanced pyruvate kinase(PK) activity and increased translocation of PKM2 into mitochondria. We then found that GACAT2 overexpression could reverse the damage to mitochondrial function and cementoblastic differentiation of PDLSCs induced by inflammation and that this effect could be abolished by PKM1/2 knockdown. Our data indicated that by binding to PKM1/2 proteins, the lnc RNA GACAT2 plays a critical role in regulating mitochondrial function and cementogenesis in an inflammatory environment.

急性缺血性脑卒中患者血清中同型半胱氨酸与炎症反应及氧化应激的关联性分析

目的:探讨同型半胱氨酸(Hcy)与炎症反应及氧化应激的相关性,分析其在急性缺血性脑卒中(AIS)发生发展中的作用。方法:选取首次发病的38例AIS患者作为AIS组,并按照病例对照研究原则,选取同期体验的健康体验者45名作为对照组。采用酶联免疫吸附试验(ELISA)检测2组研究对象血清中Hcy水平和炎症因子白细胞介素(IL)-6及肿瘤坏死因子α(TNF-α)水平,免疫比浊法检测2组研究对象血清中超敏C反应蛋白(hs-CRP)水平,化学比色法检测2组研究对象血清中丙二醛(MDA)水平和超氧化物歧化酶(SOD)活性。采用Pearson相关分析法分析AIS患者血清Hcy水平与炎症因子及氧化应激指标水平的相关性。结果:与对照组比较,AIS组患者血清中Hcy、hs-CRP、TNF-α、IL-6和MDA水平均明显升高(P<0.05),SOD活性明显降低(P<0.05)。AIS患者血清Hcy水平与hs-CRP、TNF-a、IL-6和MDA水平呈正相关关系(r=0.615,P<0.05;r=0.632,P<0.05;r=0.598,P<0.05;r=0.612,P<0.05),与SOD活性呈负相关关系(r=-0.325,P<0.05)。结论:AIS患者血清中Hcy水平与炎症因子及氧化损伤有密切关联。Hcy能够促进氧化自由基及炎症因子产生,并对内皮细胞造成损伤,在AIS发生发展过程中具有一定临床意义。

Assessment Methods Used during Clinical Years of Undergraduate Medical Education at Moi University School of Medicine, Kenya

Background: Assessment is the systematic collection, review, and use of information about educational programs undertaken to improve teaching and learning. It ensures quality in training programmes, motivates, and directs students’ learning. Assessment is also used for verification of achievement of objectives of training, feedback to students, licencing, certification, and screening of students for advanced training. It is guided by several principles, including the aims of the assessment (why assess), who to assess, timing (when to assess), what to assess, methods (how to assess), and the criteria for determining the usefulness of the assessment. Objective: To describe the assessment methods used during clinical years of the undergraduate programme at Moi University School of Medicine (MUSOM) and determine the student’s perspectives concerning the comprehensiveness, relevance, objectivity of various assessment methods and challenges faced. Methodology: The study was carried out at MUSOM and a cross-sectional study design was employed. Ten study participants were studied using convenience sampling. Data were collected using an interview guide and was analyzed using content analysis. An informed consent was obtained from the study participants. Results: The methods used during clinical years at MUSOM for assessing knowledge and its applications include multiple-choice questions (MCQ), short answer questions (SAQ), modified essay questions (MEQ), long essay questions (LEQ), and oral exam. Whereas the methods for assessing clinical competence include long case, short cases, objective structured clinical examinations (OSCE), and logbook. Students felt that MCQs were comprehensive, objective, and relevant to the curriculum content. They reported that feedback was not provided after assessments. Conclusion: The assessment methods used at MUSOM during clinical years include MCQ, SAQ, MEQ, LEQ, Short cases, long cases, and OSCE. Students reported varied perceptions of the different assessment methods but favored MCQ and OSCE over other formats for assessing knowledge and clinical skills respectively.

新型城镇化视域下安徽省碳排放网络建构研究

在发展新型城镇化及推进区域碳减排的双重压力下,探索兼顾二者综合效应的空间关联网络具有重要意义。依据安徽省新型城镇化的评价指标,结合地理空间数据和碳排数据,运用改进的引力模型和社会网络分析等方法,对2011—2019年新型城镇化视域下的安徽省碳排网络进行构建,并确定其中影响城市碳流动的关键关联要素。结果表明:①长期来看,提高新型城镇化水平对于促进区域碳减排具有重要积极作用;②安徽省中东部城市的点入度保持在较高水平,南北部城市的点出度保持在较高水平,位于中部地区的凝聚子群对周边城市的联动影响更大;③城市间相似的新型城镇化水平显著影响碳排网络的构建,其中相似的经济城镇化水平对网络影响最大。

2017—2021年柳州市食源性疾病监测结果分析

目的了解2017—2021年柳州市食源性疾病监测情况,分析其流行病学特征,为进一步提高食源性疾病监测能力策略的制订提供科学依据。方法收集2017—2021年柳州市食源性疾病监测点报告系统中数据,并对采集的粪便/肛拭子标本进行病原体检测,采用描述性流行病学方法进行统计分析。结果2017—2021年柳州市共监测病例13721例,男性6569例,女性7152例;年龄以0~4岁组病例最多(3490例,25.44%),职业以散居儿童居多(3147例,22.94%);发病高峰期为每年的7—9月(3999例,29.15%);病例的主要暴露食品为水果及其制品(2854例,20.80%),可疑暴露食品的包装方式以散装为主(4309例,31.40%),暴露场所以家庭为主(10127例,73.81%)。共采集生物标本3517份,其中致病菌检出率为11.57%,主要为沙门菌(6.11%),集中在5—10月(80.84%),诺如病毒检出率为8.94%,主要集中在1—3月(3.57%),年龄、职业、季节组内病原体检出率差异有统计学意义(P<0.001)。结论柳州市食源性疾病发病高峰期为7—9月,高危人群为0~4岁儿童,主要暴露场所以家庭为主,相关部门应在高峰期加强对以上高危人群食源性疾病的监测和预防,加强对家庭食品加工安全的宣教;生物标本检测主要检出的病原体为沙门菌和诺如病毒,提示相关部门应加强此类微生物易污染食品的监督监测,做出及时预警和宣传。

不同调水方式对巢湖水质影响模拟

引调水工程是目前用来改善湖泊水质的重要手段,然而引调水的调水路线、来水水量以及来水水质对湖泊水质改善效果都至关重要。本文以“引江济巢”工程为例,针对巢湖的浅水湖泊特征,考虑引调水入湖后不仅对水量和水质有直接改善作用,还可能因为湖区水动力条件改变及内源释放影响水质,通过构建二维水动力水质模型,模拟不同调水路线、水量下湖区水动力条件,进一步考虑不同来水水质和底泥释放对水质改善的影响。结果显示,调水对流场的扰动在丰水年较弱、枯水年较强,流量对湖区水质影响随流量增大而增强,来水水质的优劣是决定湖区水体水质是否改善的关键。整体而言,西湖区受调水影响较小,东湖区能够对全湖水质变化起到指示作用。调水方案应基于湖泊实际水量与水质状态综合考虑调水流量与水质制定。

紧凑型混合励磁三相饱和铁芯型故障限流器

加装饱和铁芯型故障限流器是限制高压系统短路电流的有效方法,但其需要与外加的限流空心电抗器配合,导致整个限流系统占地面积和体积很大。因此,基于非正交解耦原理提出了一种紧凑型混合励磁三相饱和铁芯型故障限流器(compact hybrid-biased three-phase saturated core fault current limiter,CTFCL),其具有占地面积和体积小的优点。首先,提出了含非正交解耦绕组的CTFCL拓扑。其次,建立了CTFCL的等效电磁路模型,分析了其工作原理。然后,给出CTFCL的参数设计准则,搭建了220 kV的有限元模型,仿真验证了CTFCL的限流效果和电磁特性。最后,设计并研制出小容量样机,开展了实验研究。仿真和实验结果均证明了该文所提CTFCL的有效性,CTFCL对各种短路均有良好的限制效果,且对比得到CTFCL限流系统占地面积和体积较传统三相SCFCL限流系统分别减少了44%和26%,适合实际高压系统的安装与应用。

脂代谢紊乱破坏线粒体功能导致大鼠动脉粥样硬化形成

目的通过大鼠高脂饮食模型了解脂代谢相关基因mRNA表达水平和线粒体功能在主动脉粥样硬化形成中的作用。方法高脂饮食联合维生素D3建立大鼠动脉粥样硬化模型,检测血清中血脂指标以及脂质代谢基因和线粒体合成和分解基因mRNA表达水平。结果模型组主动脉和颈动脉动脉粥样硬化形成明显,并且随着时间的延长病变加重。与对照组比较,模型组Lp(a)、TC、TG和LDL-C水平明显高于对照组(P<0.05),apoB100和HDL-C差异无统计学意义(P>0.05)。另外,模型组主动脉组织脂代谢相关基因SREBF2、LDL、HMGCR、FDFT1、HMGCS 1、LPL和DHCR24基因以及线粒体融合和分解基因MFN2、Drp1 mRNA表达水平明显增高(P<0.05),ABCA和SQLE mRNA表达水平无明显变化(P>0.05)。结论高脂饮食导致血脂增高是动脉粥样硬化形成的关键。主动脉病变组织脂质代谢基因mRNA表达水平明显增高,线粒体融合和分解明显增加。

小小地质微生物演绎跨圈层的相互作用

地球系统科学特别关注跨圈层的相互作用,包括深部系统与表层系统的相互作用、表层系统海-陆-气之间的相互作用。这种庞大时空尺度的地质作用过程可以被小小的地质微生物记录下来,足见地质微生物的以小见大、见微知著特征。在二叠纪-三叠纪之交和晚奥陶世这两个完全不同场景的显生宙火山活动过程中,爆发的初期都出现了包括蓝细菌在内的海洋固氮微生物繁盛,紧接着出现了包括藻类、放射虫、有孔虫等真核微生物的繁盛,显示了火山活动引发了从原核微生物向真核微生物群落的转变过程。不仅如此,人们还发现地质微生物可以通过条带状铁建造等生物成因岩石引发了前寒武纪的火山活动,而且还可能启动了最早的板块运动。地质微生物不仅对火山活动这一与碳循环有关的跨圈层地质作用具有很灵敏的响应和反馈能力,而且还能示踪表层系统复杂的海-陆-气相互作用及其物质传输过程。利用地质微生物的诸多干湿古气候代用指标,发现了中国东部地区不同时间尺度干湿状况的三极模态空间变化格局,而且还识别出了西北地区与西太平洋海洋上层热量有关的极端干旱事件。地质微生物记录的这些干湿状况是高纬与低纬的海-陆-气相互作用在水循环方面的体现。地质微生物演绎的与碳循环和水循环有关的这些跨圈层过程仅是地球系统的冰山一角,随着地球生物学的发展和技术方法的创新,越来越多的宜居地球形成之谜会被地质微生物所破解,包括地质微生物与深部过程的互馈效应、地质微生物与地球重大环境转型的关系以及地质微生物对地球生态系统演化的影响。

青钱柳苦荞膳食补充剂对大鼠的28天经口毒性试验

目的:研究青钱柳苦荞膳食补充剂对大鼠亚急性毒性。方法:将Wistar大鼠按体质量随机分为4组,即青钱柳苦荞膳食补充剂3个剂量组(1.67、3.33、6.67 g/kg)和1个常规基础饲料对照组。分别喂饲相应饲料28 d,自由进食饮水,观察大鼠体质量、食物利用率、血常规、血生化、尿液指标,大鼠麻醉后解剖进行大体观察、计算主要脏器的脏器系数并进行组织病理学检查。结果:实验组大鼠的体质量增长正常,未见明显毒性反应,其血常规、血生化、尿液指标、脏器系数与对照组比较差异均无统计学意义(均为P>0.05)。大鼠解剖时大体观察未发现明显异常。个别实验组大鼠心、肾脏质量与对照组比较差异具有统计学意义(P<0.05),病理组织学检查未发现青钱柳苦荞膳食补充剂引起的典型病理组织学改变和特异性损伤改变。结论:在本实验条件下,该青钱柳苦荞膳食补充剂经大鼠28天经口毒性试验未见明显的毒性作用。

交流微电网谐波功率分布式共享控制策略

交流母线电压的电能质量是微电网分布式控制的关键问题之一,该文将含逆变器接口的分布式发电机连接到微电网母线上,重点研究了含非线性负荷的微电网谐波功率共享问题。为了解决非线性负荷引起的电压畸变,设计了谐波下垂控制器和模型预测电压控制器,替代传统的电压电流双闭环控制。在此基础上,提出了一种基于有限集模型预测控制的分布式协同一致协议,使每个分布式发电单元的谐波功率在公共耦合点均匀分布。该方法可以提高微电网系统的可靠性和灵活性,防止电网扰动和馈线阻抗失配,使谐波功率在分布式发电机组之间精确地按比例分配。仿真结果表明,该控制策略在实现谐波功率共享和改善公共耦合点电压谐波失真方面具有良好的效果。

黄河流域(甘肃段)水资源与其他自然资源耦合协调关系研究

本文基于黄河流域(甘肃段)2009、2012、2015、2018、2021年57个县级行政区面板数据,利用耦合协调度模型测算并分析了水资源与耕地、园地、林地、草地、湿地的耦合协调关系及时空演变规律。结果表明:①研究期内黄河流域(甘肃段)水资源与耕地、园地、林地、草地、湿地的两两耦合协调关系呈不同发展规律与空间分异特征。总体上,水资源与草地、耕地、园地的耦合协调度相对较高,与林地、湿地的耦合协调度相对较低。②水资源与耕园林草湿整体上呈耦合、协调发展趋势,在空间上呈东北低、西南高的分布特征,在时间变化上未有明显波动。③研究时段内未出现明显的高耦合-高协调演化趋势,表明黄河流域(甘肃段)各类自然资源空间分布和数量分布不均衡,未来应重视设计差异化的自然资源协调发展路径,引导各类自然资源向更有序、协调的方向发展。

巴基斯坦新特提斯构造–岩浆演化与重要金属成矿作用

巴基斯坦在大地构造位置上处于印度、欧亚和阿拉伯三大板块的汇聚带,正同时发生着大陆碰撞和大洋俯冲作用,是研究地球系统深部圈层相互作用与成矿效应的绝佳天然实验室。但是,目前对于巴基斯坦构造演化与成矿作用的研究还不系统,对于巴基斯坦的大型–超大型矿床形成的背景和机制仍不清楚。笔者针对巴基斯坦不同类型的优势矿种开展了深入解剖和对比研究,系统梳理最新研究进展,围绕巴基斯坦新特提斯构造–岩浆演化与成矿作用响应的关键科学问题,分析铜矿、铬铁矿、铅锌矿以及碳酸岩有关的稀土矿床等重要金属成矿类型形成的构造环境以及与区域重大地质事件的耦合关系,总结巴基斯坦区域成矿规律,为资源潜力分析和境内外找矿勘查提供依据。

Causal Analysis Between Rice Growth and Cadmium Accumulation and Transfer under Arbuscular Mycorrhizal Inoculation

Cadmium(Cd)contamination in rice has been a serious threat to human health.To investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was conducted.The results indicated that AMF significantly increased rice biomass,with an increase of up to 40.0%,particularly in root biomass by up to 68.4%.Notably,the number of prominent rice individuals also increased,and their plasticity was enhanced following AMF inoculation.AMF led to an increase in the net photosynthetic rate and antioxidant enzyme activity of rice.In the AMF treatment group,the Cd concentration in the rice roots was significantly higher(19.1%‒68.0%)compared with that in the control group.Conversely,the Cd concentration in the rice seeds was lower in the AMF treatment group,indicating that AMF facilitated the sequestration of Cd in rice roots and reduced Cd accumulation in the seeds.Path coefficients varied across different treatments,suggesting that AMF inoculation reduced the direct impact of soil Cd concentration on the total Cd accumulation in seeds.The translocation of Cd was consistently associated with simultaneous growth dilution and compensatory accumulation as a result of mycorrhizal effects.Our study quantitatively analyzed this process through path analysis and clarified the causal relationship between rice growth and Cd transfer under the influence of AMF.

江西上湖遗址的石英光释光年代及其信号晒退研究

可靠的年代学框架是考古学研究的基础,然而考古遗址的沉积过程通常比较复杂,这可能会对光释光测年造成很大的问题。本研究利用石英单片再生剂量法对江西上湖遗址的6个样品进行了光释光年代测定,通过不同粒径石英测年结果的对比分析上湖遗址样品的释光特性和晒退程度,并为遗址文化层提供初步的年代结果。(1)基于三个样品进行了不同粒径(大测片)石英光释光测年结果对比,可知4~11、38~63和63~90μm三个组分的光释光年龄范围分别在50~63、67~78和71~94 ka。(2)对所有样品的粗颗粒(63~90μm)进行的小测片测试结果非常离散,这表明样品存在晒退不均匀的问题;据最小年龄模型计算得到SH01-06的年龄结果分别为:4.1±0.9、6.8±1.9、32±4、47±8、28±4和28±4 ka,比不同粒径的大测片结果更加年轻,表明所有粒径组分均存在信号晒退问题。(3)研究初步确立了上湖遗址古人类活动的时间在距今30 ka左右,晚于47 ka,但该年龄结果仍然可能被高估。

基于空间模拟的都市圈旅游景区综合交通可达性分析——以长株潭都市圈为例

综合交通可达性对当代都市圈的旅游景区服务质量和游客体验有重要作用。文章以长株潭都市圈为例,通过空间数据库构建、出发点玫瑰图构建、交通分担率测算、交通接驳时间计算、交通方式可达性分析、景区综合交通可达性结构分析等空间模拟步骤,深入归纳其旅游景区综合交通可达性的空间分布特征及问题。结果表明:长株潭都市圈中旅游景区综合交通可达性的空间分布呈现出由中心城区向边缘区域的“低-高-低”趋势。旅游景区对高速公路依赖显著,轨道交通作用发挥不足,各类交通之间接驳不畅,部分景区入口设计存在问题。文章据此提出宏观交通规划、中观交通组织、微观交通设计3方面的优化措施。文章通过对旅游交通的前端、中端、末端环节全过程分析,构建都市圈旅游景区综合交通可达性的研究框架。在交旅融合背景下,对于优化都市圈的旅游交通系统具有规划和管理的启发作用。