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Miocene Bahean stratigraphy in the Longzhong Basin, northern central china and its implications in environmental change

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Science china Earth Sciences 2006年第12期49卷 1270-1279页

作者： LI Jijun1,2, ZHANG Jun1, SONG Chunhui1, zhao Zhijun2, ZHANG Yong1, wang Xiuxi 1, ZHANG Jianming1 & CUI Qiaoyu1 1. Key Laboratory of Western china’s Environmental Systems (Ministry of Education) & college of Earth and Environment Sciences, Lanzhou university, Lanzhou 730000, china 2. Jiangsu Key Laboratory of Environmental Change and Ecological Construction & college of geography, Nanjing normal university, Nanjing 210097, china 1. Key Laboratory of Western china’s Environmental Systems (Ministry of Education) & college of Earth and Environment Sciences Lanzhou University Lanzhou 730000 China 2. Jiangsu Key Laboratory of Environmental Change and Ecological Construction & college of geography Nanjing Normal University Nanjing 210097 China

Fossil mammal-riched Neogene strata are widely distributed in the southeast corner of the huge Longzhong Basin at Tianshui, Gansu Province, northern central china. Hipparion weihoense, a typical member of late Middle Miocene Bahean stage, was recently excavated at Yaodian along a well-exposed outcrop. Owing to the importance of the Bahean stage in the mammalian evolution and its potential for environmental change, we suggested a name of Yaodian Formation for the stratigra- phy, which is correlated to the Bahe Formation at Lantian, Shaanxi. High resolution paleomagnetic dating of the section shows that the Yaodian Formation covers the period between 11.67 Ma and 7.43 Ma, with the site bearing Hipparion weihoense being estimated at about 10.54―10.30 Ma, providing first magnetostratigraphic chronology for the Bahean Stage. The Yaodian Formation consists of fluvial channel deposits (11.67―10.40 Ma) at the bottom, floodplain deposits in the middle (10.40―9.23 Ma) and shallow lake sediments at the top (9.23―7.43 Ma). This upward fining sequence suggests that the relief in nearby mountain ranges such as West Qinling to the south and Huajia Ling to the north was greatly reduced after long-term denudation, fluvial transport capacity was low, and finally the drainage system was disintegrated, replaced with broad-shallow lakes in which only fine sediments like mud and marlite were deposited, indicating an old stage of development of a planation surface. A remarkable shift in ecology and climatic environment was found at 7.4―7.7 Ma when paleoclimate changed from early warm humid to late dry as indicated by sedimentary facies changed from early shallow lake sequence to late eolian red clays and a former coniferous-deciduous mixed forest was replaced by grassland, leading to great growth of Hipparion Fauna of Baodean stage in the region. Therefore, it is estimated that the present high relief of Qinling and drainage pattern did not come into being until Late Pliocene in response

关键词： Bahean stage,magnetostratigraphy,Yaodian Formation,Neogene,Longzhong Basin.

二氧化碳浓度增加和气候变暖导致太白山林线树木生长与氮有效性关系减弱

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Journal of Plant Ecology 2024年第1期17卷 148-164页

作者： Lelong Yin Xiaohong Liu Xiaomin Zeng Ziyi wang Guobao Xu Liangju zhao Qiangqiang Lu Lingnan Zhang Xiaoyu Xing School of geography and tourism Shaanxi Normal UniversityXi'an 710119China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity College of Urban and Environmental SciencesNorthwest UniversityXi'an 710069China Key Laboratory of Soil Resource&Biotech Applications Shaanxi Academy of SciencesXi'an Botanical Garden of Shaanxi Province(Institute of Botany of Shaanxi Province)Xi'an 710061China Qinling National Botanical Garden Xi'an 710061China

全球气候变暖、大气二氧化碳浓度(C_(a))升高和氮有效性正对全球森林生态系统产生深远影响,尤其是在高海拔林线地区。本研究结合树木生长指标和树轮稳定同位素指标,探讨了太白山林线树种太白红杉(Larix chinensis)对环境胁迫的生理生态... 详细信息

全球气候变暖、大气二氧化碳浓度(C_(a))升高和氮有效性正对全球森林生态系统产生深远影响,尤其是在高海拔林线地区。本研究结合树木生长指标和树轮稳定同位素指标,探讨了太白山林线树种太白红杉(Larix chinensis)对环境胁迫的生理生态响应。研究结果表明,近60年来太白红杉的生长速度显著增加,且该林线树木生长对春季温度特别敏感。太白红杉的潜在水分利用效率(iWUE)的持续上升与大气二氧化碳浓度升高和气候变暖紧密相关,共同促进了树木的生长。1851-1964年,树轮δ^(15)N随树木生长速度的加快逐渐增大;1964年之后转变为不显著的下降,打破了原有的碳-氮平衡。分析结果表明,自20世纪60年代以来气候变暖和iWUE的迅速增加已经取代氮有效性成为树木生长的主要驱动因子。随着树木持续加速生长,氮有效性在未来可能会显著下降甚至供不应求。本研究深入揭示了植物对生长环境变化响应的生理生态机制,这将提高我们预测未来高海拔地区森林生态系统演变的能力。

关键词：树轮稳定同位素高山林线植被气候变暖 CO_(2)肥化效应太白山

基于遥感时-空-谱特征及随机森林模型的土壤重金属空间分布预测

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环境科学 2024年第3期45卷 1713-1723页

作者：王泽强张冬有徐夕博王兆鹏杨东宇宋晓宁哈尔滨师范大学地理科学学院哈尔滨150025 枣庄学院旅游与资源环境学院枣庄277160 北京师范大学地表过程与资源生态国家重点实验室北京100875

获取土壤重金属的含量特征及空间分布是预防土壤污染和制定环保政策的关键.选取济南市长清区为研究区,系统采集304处表层土壤样品(0~20 cm),利用多源遥感数据构建土壤重金属的光谱特征、时间特征和空间特征;进一步采用相关分析法选择出... 详细信息

获取土壤重金属的含量特征及空间分布是预防土壤污染和制定环保政策的关键.选取济南市长清区为研究区,系统采集304处表层土壤样品(0~20 cm),利用多源遥感数据构建土壤重金属的光谱特征、时间特征和空间特征;进一步采用相关分析法选择出与土壤重金属密切相关的时-空-谱特征,并将其作为输入自变量,实测土壤砷(As)含量值为因变量,建立基于随机森林(RF)算法的空间预测模型,完成土壤重金属的含量估算和空间分布预测.结果表明:(1)As含量均值超出背景值43.17%,低于农用地土壤污染风险规定的筛选值和管控值,表明As在土壤中出现富集,但处于可管控范围内.(2)在单个遥感特征构建的土壤重金属空间预测模型中,精度由高到低依次为:空间特征(RPIQ=3.87)>时间特征(RPIQ=2.57)>光谱特征(RPIQ=2.50),空间特征对土壤重金属空间预测最为重要.(3)基于“时间-空间”、“时间-光谱”和“空间-光谱”组合特征的土壤重金属空间预测模型均优于单个特征构建的模型,其精度系数RPIQ值分别为4.81、 4.21和4.70.(4)利用“时间-空间-光谱”特征组合输入的随机森林模型达到最佳的空间预测精度(R^(2)=0.90;RMSE=0.77;RPIQ=5.68).(5)As在空间分布上从西北到东南含量逐步降低,主要受到黄河冲淤积和工业活动影响.研究采用的遥感时-空-谱特征结合随机森林算法的土壤重金属空间预测技术,可为土壤污染防治及环境风险管控提供有效的方法支持.

关键词：土壤砷(As) 随机森林(RF) 遥感时-空-谱特征空间分布预测

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中国人口流动网络中的语言纽带效应

地理学报 2024年第4期79卷 873-889页

作者：赵梓渝王士君李卓伟韩钟辉青岛大学旅游与地理科学学院青岛266071 东北师范大学地理科学学院长春130024 中国海洋大学管理学院青岛266100

本文利用2019年腾讯人口迁徙与中国语言分布数据,揭示方言相似性对于中国人口流动影响的语言纽带效应,并进一步探究其时空异质性、交通方式异质性、空间距离对其影响的调节作用。研究发现:①方言相似性能够促进中国人口城际流动网络的... 详细信息

本文利用2019年腾讯人口迁徙与中国语言分布数据,揭示方言相似性对于中国人口流动影响的语言纽带效应,并进一步探究其时空异质性、交通方式异质性、空间距离对其影响的调节作用。研究发现:①方言相似性能够促进中国人口城际流动网络的路径形成概率与关系强度,形成了人口流动网络中的语言纽带效应。地理距离和语言距离分别可视为人口流动的显性和隐性空间成本;②语言纽带效应存在时空异质性和交通方式异质性。地区间的方言相似性每增加一个单位,在“春运”和日常阶段下,中国人口流动网络的路径形成概率分别增加47.7%、49.5%,流动强度分别增加17.1%、9.9%。语言纽带效应对于不同汉语方言区、不同交通方式的人口流动的影响存在正负与程度差异,展示出其对于中国人口流动影响的空间差异与地理含义;③语言纽带效应受到空间衰减规律的制约,并且在不同交通方式和时间段下呈现出差异性和复杂性。本文扩展了当前以经济、社会、人口学特征为主要视角的中国人口流动影响因素研究,对于揭示中国人口流动驱动机制具有科学意义,对于多民族融合的中国社会治理和文化多样性保护具有实践价值。

关键词：人口流动 “春运” 汉语方言语言纽带文化纽带中国

大学生体力活动与轻度抑郁症状及额叶α功率不对称的相关

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中国心理卫生杂志 2024年第2期38卷 180-185页

作者：王相周晓静裘莎丽臧育恒王芃王靖赵津磊辛鑫赵群尹所望王兴上海体育学院体育教育学院上海200438 上海立信会计金融学院体育与健康学院上海201600 东华大学体育部上海201620

目的:探讨大学生体力活动与轻度抑郁症状及额叶α功率不对称的相关。方法:选取有轻度抑郁症状[抑郁自评量表(SDS)得分53~62分]的大学生70例及正常对照组70例,测量安静闭目清醒状态下额叶α功率,使用国际体力活动短卷测量总体力活动(PA)... 详细信息

目的:探讨大学生体力活动与轻度抑郁症状及额叶α功率不对称的相关。方法:选取有轻度抑郁症状[抑郁自评量表(SDS)得分53~62分]的大学生70例及正常对照组70例,测量安静闭目清醒状态下额叶α功率,使用国际体力活动短卷测量总体力活动(PA)。结果:有轻度抑郁症状的大学生总PA得分(P<0.001)、右额α功率(P<0.05)、额叶α功率不对称(FAA)均低于正常对照组(P<0.001)。有轻度抑郁症状的大学生总PA得分(r=-0.29,P<0.05)和FAA (r=-0.41,P<0.001)与SDS得分呈负相关,总PA得分与FAA呈正相关(r=0.34,P <0.01)。结论:有轻度抑郁症状的大学生存在体力活动得分减少及额叶α功率右偏侧化现象,体力活动与抑郁症状及额叶α功率不对称三者间存在相关。

关键词：抑郁症状脑电图额叶α功率不对称体力活动

Status of aquatic organisms resources and their environments in Yangtze River system(2017-2021)⋆

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Aquaculture and Fisheries 2024年第5期9卷 833-850页

作者： Haile Yang Li Shen Yongfeng He Huiwu Tian Lei Gao Jinming Wu Zhigang Mei Nian Wei Lin wang Tingbing Zhu Feifei Hu Jinling Gong Hongchun Du Xinbin Duan Huatang Deng Daoqun wang Fengyue Zhu Yunfeng Li Fan Wu Huijun Ru Yan Zhang Junyi Li Junlin Yang Yuntao Zhou Dongdong Fang Yinping wang Danqing Lin Yanping Yang Peijie Li Silei Liu Jian Yang Ping Zhuang Sikai wang Tao Zhang Gang Yang Wenbo Yang Lilai Yuan Kun Cao Shuo Xu Huiyuan Liu Zhiqiang Liang Chongrui wang Hong Li Xiping Yuan Xin Yang Yilong Fu Yanping Zhang Haixin Zhang Zhiying Tao Sheng wang Xiaoping Gao Binsong Jin Kemao Li Guojie wang Shenglong Jian Yingqin Li Chenjiang Xue Chunyun Lei Shaowei Xue Yi Sun Bin Zhu Ke Shao Xingkun Hu Meihua Xiong Jun Du Bin He Tao Yan Yingying Huang Yuanchao Zou Biwen Xie Yongming wang Bin Li Fei Liu Yaoyao Zhang Fei Fan Zhijian wang Jing Huang Haoran Gu Hailong Ge Yan Dan Yan Li Shuqiao wang Chuang Zhang Lu Zhou Xue wang Sheng Zeng Yan Xiang Xugang He Jianhui Qin Chengxing Xia Jie Hou Yifu Shi Lifang Gao Zhiqiang Zhu Hongbao Shen Yun Du Xuejun Duan Jiawu Xiong Deguo Yang Shaoping Liu zhaohui Ni Hui Zhang Kai Liu Feng zhao Yingren Li Jianwei wang Qiwei Wei Yangtze River Fisheries Research Institute Chinese Academy of Fishery SciencesWuhan430223China Institute of Hydrobiology Chinese Academy of SciencesWuhan430072China Fishery Resource and Environment Research Center Chinese Academy of Fishery SciencesBeijing100141China Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization Ministry of Agriculture and Rural AffairsFreshwater Fisheries Research CenterChinese Academy of Fishery SciencesWuxi214081China East china Sea Fisheries Research Institute Chinese Academy of Fishery SciencesShanghai200090China Institute of Fisheries Engineering Chinese Academy of Fishery SciencesBeijing100141China Hunan Fisheries Science Institute Changsha410153China Jiangxi Fisheries Research Institute Nanchang330039China Jiujiang Academy of Fishery Sciences Jiujiang332000China School of Life Sciences Nanchang UniversityNanchang330031China Qinghai Provincial Fishery Technology Extension Center Xining810012China Yunnan Academy of Fishery Sciences Kunming650111China Institute of Hydroecology Ministry of Water Resources and Chinese Academy of SciencesWuhan430079China Fisheries Institute Sichuan Academy of Agricultural SciencesChengdu611731China School of Life Sciences Neijiang Normal UniversityNeijiang641100China School of Life Sciences Southwest UniversityChongqing400715China Chongqing Fishery Sciences Research Institute Chongqing401120China Guizhou Fisheries Research Institute Guiyang550025China college of Fisheries Huazhong Agricultural UniversityWuhan430072China Hubei Fisheries Science Research Institute Wuhan430070China Shaanxi Fisheries Research Institute Xi’an710086China Innovation Academy for Precision Measurement Science and Technology Chinese Academy of SciencesWuhan430077China Nanjing Institute of geography and Limnology Chinese Academy of SciencesNanjing210008China Central South Inventory and Planning Institute of State Forestry and Grassland Administration Changsha410014China

The Yangtze River is the mother river of *** promote the aquatic ecosystem protection of the great river,the Project of Yangtze Fisheries Resources and Environment Investigation(2017-2021)supported by the Ministry of Agriculture and Rural Affairs,*** carried out by 24 institutes and universities that located in the Yangtze River basin surveys the status of(1)fish species composition and spatial distribution,(2)current fish abundance,(3)endangered fishes,(4)Yangtze finless porpoise,(5)aquatic eco-environments,(6)water-level fluctuation areas,(7)capture fisheries and recreational fisheries of the Yangtze River mainstream and 10 of its main tributaries,including Yalong River,Heng River,Min River(including Dadu River),Chishui River,Tuo River,Jialing River,Wu River,Han River,Dongting Lake and Poyang *** results showed that there were 443 fish species(belonging to 163 genus,37 families,and 18 orders)before 2017,but only 323 fish species(including 15 new recorded exotic species)were recorded in the project of *** them,Cyprinus carpio,Carassius auratus,Hypophthalmichthys molitrix,Pelteobagrus fulvidraco,Coilia brachygnathus,Silurus asotus,Saurogobio dabryi,Ctenopharyngodon idellus,Pelteobagrus nitidus,Hemiculter leucisculus,Siniperca chuatsi,Coreius heterodon,Culter alburnus,Parabramis pekinensis,and Aristichthys nobilis were the dominant species across the whole Yangtze River *** is estimated that there were 886 million individuals weighing 124.8 million kg,merely equivalent to 27.3%of the resources in 1950s,30.9%of the resources in 1960s,or 58.7%of the resources in *** the new list of protected fishes that recorded in the Yangtze River system,only 15 of 29 were collected in this project of *** gladius has been affirmed to be Extinct by International Union for Conservation of Nature(IUCN).The wild individuals of Tenualosa reevesii and Luciobrama macrocephalus have disappeared for many years and maybe have been extinct

关键词： Fishes Yangtze finless porpoise Resources Aquatic ecosystem Fisheries Background investigation Yangtze river system

Spatio-temporal Dynamic of Quality of Life of Residents, Northeast china

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Chinese Geographical Science 2016年第5期26卷 623-637页

作者： CHENG Yeqing wang Ying wang Zheye DU Na SUN Yu zhao zhizhong college of geography and Environmental Sciences Hainan Normal University Department of geography Kent State University Northeast Institute of geography and Agroecology Chinese Academy of Sciences

Quality of life(QOL) is a hotspot issue that has attracted increasing attention from the Chinese Government and scholars, it is also a vital issue that should be addressed during the cause of ′establishing overall well-off society′. Northeast china is one of the most import old industrial bases in china, however, the industrial structure of heavy chemical industry and the development mode of ′production first, living last′ have leaded to series of social problems, which have also become a serious bottleneck to social stability and economic sustainable development. Through applying the methods of BP neural network, exploratory spatial data analysis(ESDA) and spatial regression model, this paper examines the space-time dynamics of QOL of the residents in Northeast china. We first investigate the indexes of QOL of the residents and then use ESDA methods to visualize its space-time relationship. We have found a spatial agglomeration of QOL of the residents in middle-southern Liaoning Province, central Jilin Province and Harbin-Qiqihar-Daqing area of Heilongjiang Province. Two third of the counties are low-low spatial correlation, and the correlative type of about 60% of the prefecture level areas keeps stable, indicating QOL of the residents in Northeast china shows a certain character of path dependence or spatial locked. We have also found that economic strength and development levels of service industry have positive and obvious effect on QOL of the residents, while the effect of such indexes as the social service level and the proportion of the tertiary industries are less.

关键词： quality of life (QOL) BP neural network exploratory spatial data analysis (ESDA) spatial regression model Northeast china

温度和共混浓度对激基复合物与电致激基复合物共存体系的磁效率调控

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科学通报 2024年第4期69卷 596-605页

作者：吴雨廷朱洪强赵茜刘俊宏彭腾汪波熊祖洪西南大学物理科学与技术学院重庆400715 重庆师范大学物理与电子工程学院重庆401331

激基复合物(exciplex)和电致激基复合物(electroplex)经常同时产生于体异质结的有机发光二极管(organic light emitting diodes,OLEDs),有报道称利用这两种发射态共存的器件实现了高效率发光.器件高效率的物理机制与共存体系中自旋对态(... 详细信息

激基复合物(exciplex)和电致激基复合物(electroplex)经常同时产生于体异质结的有机发光二极管(organic light emitting diodes,OLEDs),有报道称利用这两种发射态共存的器件实现了高效率发光.器件高效率的物理机制与共存体系中自旋对态(spin-pair states)的微观过程有关,相关微观过程还有待深入研究.本文以特征的有机磁场效应(organic magnetic field effects)作为主要探测工具,通过改变器件的工作温度和给体与受体的共混比例来研究这种双发射态共存体系中自旋对态的演变过程.实验结果表明:降低发光器件的环境温度不仅会减弱从高能激基复合物到低能电致激基复合物的Dexter能量传递过程,而且因器件偏压增高还会引起电致激基复合物电荷转移(charge-transfer,CT)态的场致解离,使其数量较少,导致其CT态的反向系间窜越(reverse intersystem crossing,RISC)过程减弱.另外,增加发光层中给体的浓度会引起电荷注入更不平衡,增强过剩的空穴载流子与电致激基复合物的解离反应,这也会减弱电致激基复合物CT态的RISC过程.因此,温度降低或给体含量增多,器件的磁效率(magneto-efficiency,Mη)从原来受RISC过程主导的负磁效应转化为受系间窜越(intersystem crossing,ISC)过程主导的正磁效应.本工作有利于深入理解激基复合物和电致激基复合物共存体系中自旋对态的物理微观机制.

关键词：有机发光二极管磁效率反向系间窜越激基复合物电致激基复合物

重大公共卫生安全事件下城市居民对绿地类型及生态系统服务的需求时空演变特征

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生态学报 2024年第10期44卷 4157-4169页

作者：赵午冬李旭谱张立伟彭立娴刘煜王壮壮焦磊王浩陕西师范大学地理科学与旅游学院西安710119 中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085

全球范围内频发的重大公共卫生安全事件可以改变城市居民的生活方式,并对居民福祉造成损害。为了探究居民对城市绿地类型及其生态系统服务的需求变化,以期使城市居民在重大公共卫生事件发生时更好地从城市绿地中获益,主要运用问卷调查数... 详细信息

全球范围内频发的重大公共卫生安全事件可以改变城市居民的生活方式,并对居民福祉造成损害。为了探究居民对城市绿地类型及其生态系统服务的需求变化,以期使城市居民在重大公共卫生事件发生时更好地从城市绿地中获益,主要运用问卷调查数据,使用Kruskal-Wallis检验、聚类分析和空间自相关分析等方法对新冠疫情(COVID-19)发生的前、中、后三个时期城市居民对城市绿地类型及其生态系统服务需求偏好的时空演变特征进行了分析。结果显示:(1)随着时间演变,居民对同时期内同种类型的城市绿地以及生态系统服务的需求差异变小。在前期和中期,居民需求最强烈的绿地类型分别是附属绿地、公园绿地;需求最不强烈的绿地类型都是区域绿地。在前期,居民对生态系统服务的需求普遍较为强烈,前期和中期居民需求最强烈的生态系统服务分别是美化城市和放松身心两种类型。在后期,居民需求最强烈和最小的城市绿地类型分别是附属绿地和公园绿地。(2)居民对于城市绿地类型的需求在这三个时期的空间演变程度要大于对生态系统服务需求的空间演变程度。(3)居民对于城市绿地及其生态系统服务需求的空间异质性较强,大多呈随机分布格局,只有对后期的四种绿地类型的需求呈聚集分布,主要分布在京津冀地区、内蒙古、山西省、山东省。研究结果旨在为未来重大公共卫生事件影响下城市绿地规划和生态系统服务的可持续利用提供科学支撑,以期更好地保障城市居民生活福祉。

关键词：重大公共卫生安全事件城市绿地生态系统服务聚类分析空间自相关

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