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Interdecadal variation of drought patterns and associated influencing factors in the north-south transitional zone of China

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Journal of Geographical sciences 2024年第7期34卷 1253-1279页

作者： DONG Qingdong ZHU Lianqi DUAN Zheng WANG Liyuan CHEN Chaonan LI Yanhong ZHU Wenbo GURUNG Sher Bahadur The College of geography and Environmental science Henan UniversityKaifengHenan475004China department of Physical geography and Ecosystem science Lund UniversityLundS-22362Sweden Central department of geography Tribhuvan UniversityKathmandu44600Nepal

In the context of global warming,escalating water cycles have led to a surge in drought frequency and ***,multidecadal fluctuations in drought and their multifaceted influencing factors remain inadequately *** study examined the multidecadal changes in drought characteristics(frequency,duration,and severity)and their geographical focal points within China's north-south transitional zone,the Qinling-Daba Mountains(QDM),from 1960 to 2017 using the Standardized Precipitation Evapotranspiration Index(SPEI).In addition,a suite of eight scenarios,correlation analysis,and wavelet coherence were used to identify the meteorological and circulation factors that influenced drought *** results indicate the following:(1)From 1960 to 2017,the QDM experienced significant interdecadal variations in drought frequency,duration,and severity,the climate was relatively humid before the 1990s,but drought intensified ***,the 1990s marked the period of the longest drought duration and greatest severity,while the years spanning 2010 to 2017 experienced the highest frequency of drought events.(2)Spatially,the Qinling Mountains,particularly the western Qinling Mountain,exhibited higher drought frequency,duration,and severity than the Daba *** disparity can be attributed to higher rates of temperature increase and precipitation decrease in the western Qinling Mountain.(3)Interdecadal variations in droughts in the QDM were directly influenced by the synergistic effects of interdecadal fluctuations in air temperature and *** factors modulate temperature and precipitation through phase transitions,thereby affecting drought dynamics in the *** Atlantic Multidecadal Oscillation emerges as the primary circulation factors influencing temperature changes,with a mid-1990s shift to a positive phase favoring *** East Asian Summer Monsoon and El Ni?o-Southern Oscillation are the main circulation factors a

关键词： drought standardized precipitation evapotranspiration index multidecadal shift transitional zone Qinling-Daba Mountains

Assessment of sediment connectivity using modelling and field-based approaches in the Slavíč River catchment(MoravskoslezskéBeskydy Mts,Czech Republic)

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Journal of Mountain science 2024年第3期21卷 734-753页

作者： MACUROVÁ Tereza ŠKARPICH Václav department of Physical geography and Geoecology Faculty of ScienceUniversity of OstravaChittussiho 1071000 OstravaCzech Republic

Mountain streams act as conveyors of sediments within the river continuum,where the physical transport of sediments between river reaches through the catchment or between individual parts(e.g.,between hillslopes and channels)of the catchment is *** study focused on sediment connectivity analysis in the SlavíčRiver catchment in the MoravskoslezskéBeskydy Mts in the eastern part of the Czech *** connectivity index and connectivity index target modelling were combined with an analysis of anthropogenic ***,field mapping,grain size of bed sediments and stream power analysis were used to obtain information about connectivity in the *** on the analysis and obtained results,terrain topography is the current main driving factor affecting the connectivity of sediment movement in the SlavíčRiver ***,the modelling provided valuable information about high sediment connectivity despite different recent land use conditions(highly forested area of the catchment)than those in historical times from the 16th to 19th centuries when the SlavíčRiver catchment was highly deforested and sediment connectivity was probably *** analysis of anthropogenic interventions,field mapping,grain size of bed sediments and stream power analysis revealed more deceleration of sediment movement through the catchment,decreased sediment connectivity with bed erosion,and gradual river channel process transformation in some *** mapping has identified various natural formations and human-induced changes impacting the longitudinal and lateral connectivity in the Slavíč*** instance,embankments along 48%of the river's length,both on the right and left banks,significantly hinder lateral sediment supply to the *** power index analysis indicates increased energy levels in the flowing water in the river's upper reaches(up to 404.8 W m^(-2)).This high energy is also observed in certain downstream sections(up to 337.6 W

关键词： Mountain stream Connectivity analysis Modelling Grain size analysis SlavíčRiver MoravskoslezskéBeskydy Mts

Reducing Social Media Attention Inequality in Disasters: The Role of Official Media During Rainstorm Disasters in China

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International Journal of Disaster Risk science 2024年第3期15卷 388-403页

作者： Longfei Zheng Lei Chen Fenjie Long Jianing Liu Lei Li School of geography Faculty of Geographical Science Beijing Normal University Hang Lung Center for Real Estate and department of Construction Management Tsinghua University

Unequal social media attention can lead to potentially uneven distribution of disaster-relief funds, resulting in long-term inequality among regions after disasters. This study aimed to measure inequalities in social media attention to regions during disasters and explore the role of official media in reducing such inequality. This is performed by employing social media,official media, and official aggregated statistics regarding China's rainstorm disasters. Through a set of panel-data regressions and robustness tests, three main conclusions were drawn:(1) There were inequalities among regions regarding social media attention they received during rainstorm disasters. For disasters of the same magnitude, regions with low economic outcome per capita received less attention on social media.(2) Official media can reduce inequality in social media attention during disasters. Official media statements can encourage netizens to pay attention to disaster-stricken areas, and especially the overlooked underdeveloped areas.(3) Of all the measures taken by official media, timely, accurate, and open disclosure of disaster occurrences proved to be the most potent means of leveling the playing field in terms of social media attention;contrarily, promotional or booster-type messages proved futile in this regard. These findings revealed the vulnerabilities within social media landscapes that aff ect disaster relief response, shedding light on the role of official guidance in mitigating inequalities in social media attention during such crises. Our study advises social media stakeholders and policymakers on formulating more equitable crisis communication strategies to bridge the gap in social media attention and foster a more balanced and just relief process.

关键词： China, inequality of attention Official media Rainstorm disasters Situational crisis communication theory Social media

PAL-BERT:An Improved Question Answering Model

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Computer Modeling in Engineering & sciences 2024年第6期139卷 2729-2745页

作者： Wenfeng Zheng Siyu Lu Zhuohang Cai Ruiyang Wang Lei Wang Lirong Yin School of Automation University of Electronic Science and Technology of ChinaChengdu610054China department of geography and Anthropology Louisiana State UniversityBaton RougeLA70803USA

In the field of natural language processing(NLP),there have been various pre-training language models in recent years,with question answering systems gaining significant ***,as algorithms,data,and computing power advance,the issue of increasingly larger models and a growing number of parameters has ***,model training has become more costly and less *** enhance the efficiency and accuracy of the training process while reducing themodel volume,this paper proposes a first-order pruningmodel PAL-BERT based on the ALBERT model according to the characteristics of question-answering(QA)system and language ***,a first-order network pruning method based on the ALBERT model is designed,and the PAL-BERT model is ***,the parameter optimization strategy of the PAL-BERT model is formulated,and the Mish function was used as an activation function instead of ReLU to improve the ***,after comparison experiments with traditional deep learning models TextCNN and BiLSTM,it is confirmed that PALBERT is a pruning model compression method that can significantly reduce training time and optimize training *** with traditional models,PAL-BERT significantly improves the NLP task’s performance.

关键词： PAL-BERT question answering model pretraining language models ALBERT pruning model network pruning TextCNN BiLSTM

Contrasting compositions of PM_(2.5)in Northern Thailand during La Nina(2017)and El Nino(2019)years

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Journal of Environmental sciences 2024年第1期135卷 585-599页

作者： Pavidarin Kraisitnitikul Duangduean Thepnuan Sarana Chansuebsri Nuttipon Yabueng Wan Wiriya Supattarachai Saksakulkrai Zongbo Shi Somporn Chantara Environmental science Research Center Faculty of ScienceChiang Mai UniversityChiang Mai50200Thailand department of Chemistry Faculty of Science and TechnologyChiang Mai Rajabhat UniversityChiang Mai50300Thailand Chemistry department Faculty of ScienceChiang Mai UniversityChiang Mai50200Thailand School of geography Earth and Environmental SciencesUniversity of BirminghamBirminghamB152TTUK

There have been a very limited number of systematic studies on PM_(2.5)compositions and their source contribution in Southeast *** study aims to explore the characteristics of PM_(2.5)composition collected in Chiang Mai(Thailand)during La Nina and El Nino years and to apportion their sources during smoke haze and non-haze *** average PM_(2.5)concentration of smoke haze episode in 2019(El Nino)was much higher than in 2017(La Nina).The ratios of organic carbon(OC)to elemental carbon(EC),as well as K(biomass burning(BB)tracer)to PM_(2.5),were higher during smoke haze episodes in 2019 than in 2017 indicating a significant influence from *** ratios of secondary organic carbon(SOC)levels to primary organic carbon(POC)levels during smoke haze episodes were higher than those in non-haze period,which indicated greater SOC contributions or more photo-oxidation of precursors in haze episodes with high ambient ***,the ratios of soil markers(Ca and Mg)during non-haze period were high implying that soil source contributed more to PM_(2.5)concentrations when there less BB *** positive Matrix Factorization(PMF)model revealed that the source of BB,characterized by high K fractions,was the largest contributor during smoke haze episodes accounting for 50%(2017)and 79%(2019).Climate conditions influence meteorological patterns,particularly during incidences of extreme weather such as droughts,which affect the scale and frequency of open burning and thus air pollution levels.

关键词： Climate Air pollution Metals Carbon Biomass burning Source identification

Factors determining changes in the network of marked hiking trails in the Sudetes

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Journal of Mountain science 2024年第4期21卷 1075-1099页

作者： Krzysztof KOŁODZIEJCZYK department of Regional geography and Tourism Institute of Geography and Regional DevelopmentFaculty of Earth Sciences and Environmental ManagementUniversity of WroclawNo.1Uniwersytecki Square50-137 WroclawPoland

Hiking trails are a basic type of tourist infrastructure,which,on the one hand,make areas available for tourist traffic,and on the other hand,can contribute to the protection of the natural environment(if they are well designed and maintained).Owing to the variety of performed functions,their designation is determined by several factors:natural,technical,economic,*** of trails change *** aim of this article is to determine exactly what factors influence transformations within the hiking trail networks and what is their *** this end,three study areas in the Sudetes were analysed:one on the Polish side of the Sudetes-the Table(Stołowe)Mountains,and two on the Czech side-the rock town near the village of Sloup vČechách and the central part of Zlatohorská*** analysis of changes in the shape of the networks over time was carried out,as well as surveys of institutions that were responsible for or influenced these *** areas are characterised by a significant level of changes in the trail *** the factors influencing these changes,the tourist attractiveness of the area,the resilience of the environment,the intensity of tourism traffic,the environmental transformations associated with it,the history of tourism development and land ownership changes should be considered the most *** each stage of forming networks,the key factor should be tourists’needs,including the desire to escape the urbanised *** this reason,trails should avoid roads with artificial(hard)surfaces and heavy automobile traffic.

关键词： Hiking trails Trail networks Graphs Tourist traffic Sudetes

Sedimentary Characteristics,Ages,and Environmental Significance of Gravel Deposits and Loess in Shandong,Eastern China:Regional Response to Global Change Since the Last Glacial Period

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 491-504页

作者： WANG Min KONG Fanbiao KONG Xianglun CHEN Haitao WANG Jiawei MIAO Xiaodong JIA Guangju HAN Mei XU Shujian department of geography and Tourism Qilu Normal UniversityJinan 250014China School of geography and Environment Shandong Normal UniversityJinan 250014China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection Linyi UniversitySchool of Resources and EnvironmentLinyiShandong 276005China College of Earth science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China

Investigation of rarely studied gravel layers found in the loess in Shandong Province,eastern China,reveals the fabric characteristics of two gravel layers(G1,G2)and the sedimentary characteristics of loess at the typical and well-preserved Heiyu section(HY),where,to determine the paleoclimatic changes during Marine Isotope Stage *** stimulated luminescence dates of the HY formation range from 0.26±0.02 ka to 39.00±2.00 *** addition,the ages of G1 and G2 were estimated using the Bayesian model to be 39.60-40.50 and 29.00-29.50 ka.G1 and G2 are mainly composed of fine and medium gravel,both of which were subangular to subrounded limestone,with gravel directions to NE and *** average flow velocity,average depth,and flood peak flow of G1 are 1.10 m/s,0.49 m,and 37.04 m^(3)/s,respectively,calculated using the flow energy method,whereas those of G2 are 0.98 m/s,0.38 m,and 18.38 m^(3)/s,*** of climate proxy indices show that the sedimentary environment of the gravel and loess in HY might be a regional response to global change.

关键词： paleoenvironment geochronology gravel layer sedimentology Pleistocene Shandong Province

Dendroclimatological study of Sabina saltuaria and Abies faxoniana in the mixed forests of the Qionglai Mountains,eastern Tibetan Plateau

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Journal of Forestry Research 2024年第1期35卷 72-82页

作者： Teng Li Jianfeng Peng Tsun Fung Au Jingru Li Jinbao Li Yue Zhang School of geography and Remote Sensing Guangzhou UniversityGuangzhou 510006People’s Republic of China College of geography and Environmental science Henan UniversityKaifeng 475004People’s Republic of China Institute for Global Change Biology School for Environment and SustainabilityUniversity of MichiganAnn ArborMIUSA department of Ecology and Evolutionary Biology University of MichiganAnn ArborMIUSA department of geography University of Hong KongHong Kong SARPeople’s Republic of China HKU Shenzhen Institute of Research and Innovation Shenzhen 518057People’s Republic of China

Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan ***-growth relationship analysis indicated that the two co-exist-ing species reponded similarly to climate factors,although *** was more sensitive than *** strong-est correlation was between *** chronology and regional mean temperatures from June to *** on this relationship,a regional mean temperature from June to November for the period 1605-2016 was *** explained 37.3%of the temperature variance during th period *** major warm periods and five major cold periods were *** analysis detected significant interannual and multi-decadal *** also revealed the influence of the Atlantic Multi-decadal Oscillation,confirming its importance on climate change on the eastern Tibetan Plateau.

关键词： Tree-ring analysis Mixed forests Dendroclimatology Qionglai Mountains

April-September minimum temperature reconstruction based on Sabina tibetica ring-width chronology in the central eastern Tibetan Plateau,China

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Journal of Forestry Research 2024年第2期35卷 134-145页

作者： Teng Li Jianfeng Peng Tsun Fung Au Jinbao Li School of geography and Remote Sensing Guangzhou UniversityGuangzhou 510006People’s Republic of China College of geography and Environmental science Henan UniversityKaifeng 475004People’s Republic of China Institute for Global Change Biology School for Environment and SustainabilityUniversity of MichiganAnn ArborMIUSA department of Ecology and Evolutionary Biology University of MichiganAnn ArborMIUSA department of geography University of Hong KongHong Kong SARPeople’s Republic of China HKU Shenzhen Institute of Research and Innovation Shenzhen 518057People’s Republic of China

Minimum temperatures have remarkable impacts on tree growth at high-elevation sites on the Tibetan Plateau,but the shortage of long-term and high-resolution paleoclimate records inhibits understanding of recent minimum temperature *** this study,a warm season(April–September)reconstruction is presented for the past 467 years(1550–2016)based on Sabina tibetica ring-width chronology on the Lianbaoyeze Mountain of the central eastern Tibetan *** warm periods and eight cold periods were ***-term minimum temperature variations revealed a high degree of coherence with nearby *** correlations between our reconstruction and global sea surface temperatures suggest that warm season minimum temperature anomalies in the central eastern Tibetan Plateau were strongly influenced by large-scale ocean atmospheric circulations,such as the El Ni?o-Southern Oscillation and the Atlantic Multidecadal Oscillation.

关键词： Tree-ring analysis Sabina tibetica Minimum temperatures Central eastern Tibetan Plateau Climate change