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Archaeology and Heritage Resource Management in Siuyu, Singida Region (Tanzania) 被引量:1
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作者 Makarius Peter Itambu Nazarius Michael Hongoa 《Journal of Geoscience and Environment Protection》 2016年第6期34-45,共12页
This paper was produced as a part of our ongoing research endeavors in Singida destined to provide a better understanding of early humans’ cultures, and to promote the conservation of cultural and natural heritages o... This paper was produced as a part of our ongoing research endeavors in Singida destined to provide a better understanding of early humans’ cultures, and to promote the conservation of cultural and natural heritages of the region. The overreaching goals of this research are to holistically reconstruct the archaeology of Singida by studying cultural processes over time and space. Equally important is to promote tourism in the Singida eastern axis and, to salvage the heritage assets of the region from total disappearance as evinced by the activities of modern day civilization, broadly, to shed more light about the past life ways, and the subsistence behaviours of our ancestors. Our recent archaeological reconnaissance conducted in January 2016 in Siuyu ward discovered rock paintings and a rock shelter with archeological potential (Ngaghe rock shelter), containing a large scatter of Later Stone Age (LSA) archaeological artifacts that are crucial to the unravelling of the prehistoric human behaviours in Singida. Preliminary results from our research revealed that Singida region is an ideal place for undertaking research on early human bio-cultural evolution from LSA times to the present. Data from this study will be utilized to re-write the history of Singida region, to make sure that it is sustained for future generations. Despite their rarity, uniqueness, scientific and aesthetic values, these heritage assets are neither protected by village nor regional by-laws. Before deliberate conservation measures are put in place, it is very important to have good records of the areas that are attractive to tourism, and their current state of preservation. These sites were undocumented by the previous researchers, and in certain circumstances are unknown even to the local people of the Siuyu ward. Although the archaeology of Singida east is much “terra incognita”, this article is timely, for promoting archaeo-tourism and raising public awareness on the archaeology of Singida. Additionally, this work provides a stimulus to the authorities to take action by introducing effective conservation measures for the sustainability of these priceless non-renewable resources. 展开更多
关键词 ARCHAEOLOGY Heritage Conservation Cultural and Natural Resources TOURISM
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Environmental archaeology on Longshan Culture (4500-4000 aBP) at Yuhuicun Site in Bengbu, Anhui Province 被引量:3
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作者 ZHANG Guangsheng ZHU Cheng +7 位作者 WANG Jihuai ZHU Guangyao MA Chunmei ZHENG Chaogui ZHAO Lanhui LI Zhongxuan LI Lan JIN Aichun 《Journal of Geographical Sciences》 SCIE CSCD 2010年第3期455-468,共14页
Based on the samples collected from the west wall of the ABYT2004 at Yuhuicun Site in Bengbu, Anhui Province, the multi-environmental substitute indexes such as the grain-size, Rb/Sr, zircon crystal morphology and mag... Based on the samples collected from the west wall of the ABYT2004 at Yuhuicun Site in Bengbu, Anhui Province, the multi-environmental substitute indexes such as the grain-size, Rb/Sr, zircon crystal morphology and magnetic susceptibility were analyzed. The age of archaeological strata was determined by AMS^14C dating. According to the results, combined with the information of the ancient human activities and the cultural heritage data obtained from the Longshan cultural archaeological strata, it can be concluded that (1) Before 4500 aBP, the climate was humid and water level was high in the Huaihe River and its tributaries, the drainage basin and its surrounding areas were even flooded, so the site area was submerged and there were no human activities around the site. (2) About 4500 aBP, the climate began to become drier and water level of the Huaihe River and its tributaries began to decline, thus floodplain gradually appeared, Yuhuicun Site and Longshan Culture began to appear. (3) Around 4100 aBP, the climate was humid and rainfall was abundant, which resulted in frequent flood disasters in the whole Huaihe River Basin. (4) After 4100 aBP, the climate gradually transited to be cold and dry, agricultural production was constrained to reduce the food source, Yuhuicun Site was almost abandoned. (5) The environmental information in sedimentary strata and historical records based on ancient books agree with each other. In addition, Yuhuicun Site was related to Dayu Zhishui (Yu the Great in taming the floods) in ancient books. 展开更多
关键词 Yuhuicun Site Longshan Culture 4500-4000 aBP environmental change Huaihe River Basin
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Comparison of bone artifacts from the Schöningen site in Germany and the Lingjing site in China
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作者 WANG Hua LI Zhanyang Thijs van KOLFSCHOTEN 《人类学学报》 CSSCI CSCD 北大核心 2024年第2期214-232,共19页
Similarities play an important role in the reconstruction of human physical,cultural and technological evolution.The two sites presented in this paper,the Middle Palaeolithic site Lingjing in China Layer 10 and 11 and... Similarities play an important role in the reconstruction of human physical,cultural and technological evolution.The two sites presented in this paper,the Middle Palaeolithic site Lingjing in China Layer 10 and 11 and the Lower Palaeolithic site Schöningen 13Ⅱ-4,the socalled Schöningen Spear Horizon in Germany,show striking similarities.The archaeological record of both sites includes lithic artifacts as well as a very large assemblage of fossil bones.The preservation of the material at both sites is excellent and the faunas encountered at both sites show many similarities.The faunal lists of both sites include a diverse carnivore guild,an elephant species,two different rhinoceros species,two different equids,different cervids and large bovids.Both sites also yielded bone retouchers as well as a unique record of bone hammers that show identical,unusual flaking and percussion damage.These similarities are remarkable if one takes into account the difference in age(ca 200 kaBP)and the geographical distance between the two sites of ca 8000 km.Therefore,we do not assume a close cultural link between the hominin populations active at both sites.The authors assume that the observed similarities show more or less identical,opportunistic hominin behaviour at both sites located in a comparable environment with more or less similar taphonomic conditions. 展开更多
关键词 PALAEOLITHIC open-air sites bone tools Asia EUROPE
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Classifying moisture sources associated with snowfall in the mountains of Lesotho
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作者 Alexi M.MARINAKI Jennifer M.FITCHETT 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1941-1953,共13页
An average of eight snowfall events occur each year in the eastern Lesotho Highlands.These snowfall events are typically associated with cut-off low(CoLs)systems and mid-latitude cyclones.However,the moisture sources ... An average of eight snowfall events occur each year in the eastern Lesotho Highlands.These snowfall events are typically associated with cut-off low(CoLs)systems and mid-latitude cyclones.However,the moisture sources of the snowfall are unclassified and unclear.The Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model,an air mass back trajectory model,has been used to evaluate moisture source waters locally in southern Africa and internationally in China and Europe.This study uses HYSPLIT to determine the source moisture of snow in Lesotho.A list of all 82 snowfall events in Lesotho spanning 2017 to 2022 was compiled using the Snow Report SA Instagram page,including the date and location of snowfall.A 72-hour back trajectory for each snowfall event was initiated for both Afriski and the whole of Lesotho.This amounts to models of moisture source trajectories for 28 and 82 snowfall days,respectively.These air mass pathways are classified according to their frequency per snowfall event,per month in the snow season,per year and for the full period.From this,associated moisture source regions and dominant air mass trajectories were identified.This study reports that the air mass trajectories associated with Afriski and Lesotho as a whole are very similar.The most common pathway of air mass trajectories transporting snow-bearing moisture to Lesotho was an inland trajectory from the northern regions of southern Africa.This pathway makes up 16.6%of all trajectories reported and is associated with the Angola Low,the Congo Air Boundary and the St.Helena High Pressure. 展开更多
关键词 Eastern Lesotho Highlands Afriski SNOW Cut-off Lows HYSPLIT Synoptic Climatology
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Selenga River human dispersal path in Initial Upper Paleolithic
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作者 Evgeny P RYBIN Arina M KHATSENOVICH 《人类学学报》 CSSCI CSCD 北大核心 2024年第5期780-796,共17页
Here,we consider earlier Upper Paleolithic sites in the Selenga River Basin,the main fluvial input of Lake Baikal that flows through northern Mongolia and the southwestern Transbaikal region of Russia.Lithic industrie... Here,we consider earlier Upper Paleolithic sites in the Selenga River Basin,the main fluvial input of Lake Baikal that flows through northern Mongolia and the southwestern Transbaikal region of Russia.Lithic industries from these sites can be attributed to the laminar Initial Upper Paleolithic(IUP)technocomplex,widespread in southern Siberia and Central Asia.IUP industries appear in the Selenga Basin about 45 kaBP cal.Aspects of regional typological variability and the transport of exotic raw materials over long distances indicate that these populations participated in developed exchange networks and employed high mobility targeting the acquisition of necessary raw materials.Two site types are present:quarry-workshops in northern Mongolia and generalized activity settlements in the southwestern Transbaikal.Although faunal data are limited,we interpret available information as indicating a specialization on hunting,focusing on migrating steppe game species.The distribution of sites in the mid-altitudes and landscapes of the Selenga-Orkhon geographical region and the geomorphological homogeneity of this territory also supported interregional human moves during the IUP. 展开更多
关键词 Central Asia Initial Upper Paleolithic MIGRATION raw material HUNTING
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A VGGNet-based correction for satellite altimetry-derived gravity anomalies to improve the accuracy of bathymetry to depths of 6500 m
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作者 Xiaolun Chen Xiaowen Luo +6 位作者 Ziyin Wu Xiaoming Qin Jihong Shang Huajun Xu Bin Li Mingwei Wang Hongyang Wan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第1期112-122,共11页
Understanding the topographic patterns of the seafloor is a very important part of understanding our planet.Although the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the... Understanding the topographic patterns of the seafloor is a very important part of understanding our planet.Although the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the seafloor has been precisely modeled to date,and there is an urgent need to improve the accuracy and reduce the uncertainty of underwater survey data.In this study,we introduce a pretrained visual geometry group network(VGGNet)method based on deep learning.To apply this method,we input gravity anomaly data derived from ship measurements and satellite altimetry into the model and correct the latter,which has a larger spatial coverage,based on the former,which is considered the true value and is more accurate.After obtaining the corrected high-precision gravity model,it is inverted to the corresponding bathymetric model by applying the gravity-depth correlation.We choose four data pairs collected from different environments,i.e.,the Southern Ocean,Pacific Ocean,Atlantic Ocean and Caribbean Sea,to evaluate the topographic correction results of the model.The experiments show that the coefficient of determination(R~2)reaches 0.834 among the results of the four experimental groups,signifying a high correlation.The standard deviation and normalized root mean square error are also evaluated,and the accuracy of their performance improved by up to 24.2%compared with similar research done in recent years.The evaluation of the R^(2) values at different water depths shows that our model can achieve performance results above 0.90 at certain water depths and can also significantly improve results from mid-water depths when compared to previous research.Finally,the bathymetry corrected by our model is able to show an accuracy improvement level of more than 21%within 1%of the total water depths,which is sufficient to prove that the VGGNet-based method has the ability to perform a gravity-bathymetry correction and achieve outstanding results. 展开更多
关键词 gravity anomaly bathymetry inversion VGGNet multibeam sonar satellite altimetry
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Ancient DNA unravels species identification from Laosicheng site,Hunan Province,China,and provides insights into maternal genetic history of East Asian leopards
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作者 Ming Zhang Cai-Hui Wang +9 位作者 Yu-Xin Zheng Qi-Gao Jiangzuo Ye-Mao Hou Peng Cao Qing-Yan Dai Ruo-Wei Yang Feng Liu Xiao-Tian Feng Lin-Heng Mo Qiao-Mei Fu 《Zoological Research》 SCIE CSCD 2024年第1期226-229,共4页
DEAR EDITOR,The Laosicheng site in Yongshun County,Hunan Province,China,plays an important role in elucidating the animal population composition of the region prior to the middle Qing Dynasty(approximately 300 years a... DEAR EDITOR,The Laosicheng site in Yongshun County,Hunan Province,China,plays an important role in elucidating the animal population composition of the region prior to the middle Qing Dynasty(approximately 300 years ago).This site has yielded a substantial number of animal bones,11960 of which have been identified to the species level,serving as direct evidence of ancient animal populations(Hunan Provincial Institute of Cultural Relics and Archaeology,2018). 展开更多
关键词 HUNAN ANCIENT INSIGHT
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The habitation Model Trend Calculation(MTC):A new effective tool for predictive modeling in archaeology
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作者 George Malaperdas Nikolaos Zacharias 《Geo-Spatial Information Science》 SCIE CSCD 2019年第4期314-331,I0008,共19页
The aim of this paper is to create and present a new archaeological predictive model via GIS,incorporating what archaeologists consider the most important criterion absent of similar past models,that of critical think... The aim of this paper is to create and present a new archaeological predictive model via GIS,incorporating what archaeologists consider the most important criterion absent of similar past models,that of critical thinking.The new model suggested in this paper is named habitation Model Trend Calculation(MTC)and is not only integrates the archaeological questions with a critical view,but it can be easily adjusted,according to the conditions or the questions concerning the archaeological community.Furthermore,it uses new topographical and geomorphological indexes such as Topographical Index(TPI),Hillslope and Landform Classification that give a new sense of the topographical and geomorphological characteristics of the examined area;therefore this model is a more powerful tool compared to older models that did not use new topographical and geomorphological indexes.The success of the created model is checked as a case study in the region of Messenia,Greece during the Mycenaean era.The region of Messenia is considered as one of the most important Mycenaean regions of Greece due to the great number and the importance of Mycenaean sites identified.For the present paper,140 habitation sites were divided into four hierarchical categories(centers,large villages,villages,and farms)based on the extent and the plurality of the tholos tombs that exist in the broader region and according to the hierarchical categorization used by the archaeologists who have studied the area.The new predictive model presented in this work can assist in solving a series of criticisms that have been expressed in the previous studies regarding such models.Additionally,in the case of Mycenaean Messenia,the model shows excellent results in relation to the habitats of the time. 展开更多
关键词 GIS Mycenaean Messenia predictive model ARCHAEOLOGY habitation Model Trend Calculation(MTC) analytical hierarchy process(AHP) spatial analysis
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Pollen dispersal in traditional processing of buckwheat and its application in agricultural archaeology
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作者 Yang LIU Xue SHANG +1 位作者 Pengfei SHENG Guoding SONG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第12期1792-1803,共12页
Pollen, as an important index of the paleoenvironment and ancient human agricultural activities, is also one of the significant indicators for research on buckwheat agriculture. In order to test buckwheat pollen dispe... Pollen, as an important index of the paleoenvironment and ancient human agricultural activities, is also one of the significant indicators for research on buckwheat agriculture. In order to test buckwheat pollen dispersal during each crop processing stage, we applied traditional processing simulation experiments of buckwheat crops in a modern village, to collect aerial pollen and perform statistical analysis. The result has shown that the distribution of buckwheat pollen in residential areas is closely related to human processing behaviour. Among all the processing procedures, pollen release rate is highest in the threshing and the sieving stages. The redistribution and burial of pollen during crop processing is an important reason for the prominent increase of crop pollen concentration in the cultural layer. Not only can it indicate the cultivation and processing behaviour of humans but also provide a basis for identifying the crop processing remains in archaeological sites and assessing the intensity of agricultural activities. 展开更多
关键词 BUCKWHEAT CROP processing POLLEN dispersal AGRICULTURAL ACTIVITIES AGRICULTURAL ARCHAEOLOGY
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An analysis of the interaction mechanism between the social history of medicine research and health communication from the perspective of mass communication
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作者 Jian-Liang Huang Kun-Lan Zuo Huan Liu 《History & Philosophy of Medicine》 2024年第1期14-18,共5页
The mass communication model and interactive ritual chain theory,which serve as communication paradigms in the new media era,facilitate and enhance the synergy between the fields of social history of medicine and heal... The mass communication model and interactive ritual chain theory,which serve as communication paradigms in the new media era,facilitate and enhance the synergy between the fields of social history of medicine and health communication.This study employs a comprehensive framework based on the five elements of the mass communication model:information source,communication subject,communication object,message content,and post-communication feedback.Additionally,it incorporates the interactive ritual chain theory to examine the evolving dynamics and developmental trajectory of research in the social history of medicine during the new media era.Conclusively,this paper acknowledges the existing interaction gaps in the interaction between health communication and the social history of medicine research while outlining the challenges for fostering collaboration and proposing strategic optimizations for effective integration. 展开更多
关键词 history of medicine health communication mass communication interaction mechanisms interaction ritual chain theory
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Historical retrospects and evolutionary characteristics of paleogenomic science and technology
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作者 Qiang-Yu Xiang Kun-Lan Zuo Huan Liu 《History & Philosophy of Medicine》 2024年第2期14-22,共9页
Paleogenomics is a discipline in which the extraction and analysis of DNA from ancient biological remains are studied to understand the evolutionary history of past organisms.Research on this topic has revealed the ev... Paleogenomics is a discipline in which the extraction and analysis of DNA from ancient biological remains are studied to understand the evolutionary history of past organisms.Research on this topic has revealed the evolutionary history of humans and other species,traced human migrations and genetic changes,and investigated ancient diseases and environmental influences due to its uniqueness.This paper reviews the scientific and technological history of the development of paleogenomics,including the molecular cloning era,the polymerase chain reaction(PCR)technique era,the genomics era,and the bio-data analysis era.This field explores the key technological development processes and effects of significant scientific discoveries,ranging from gene cloning technology and sequencing technology to breakthroughs and applications in big data analysis,addressing challenges such as sample contamination and trace collection analysis in paleogenomics research. 展开更多
关键词 paleogenomics history of science and technology key technologies life evolution
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The Macrolichens of Barluk Mountain National Nature Reserve, Xinjiang Province, China
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作者 Dolathan Toksun Reyhangul Mamatali +3 位作者 Haiying Yong David H. S. Richardson Mark R. D. Seaward Anwar Tumur 《Open Journal of Forestry》 2024年第4期413-432,共20页
A checklist of the macrolichens (foliose, fruticose & squamulose) of Barluk Mountain National Nature Reserve located in northwestern China is presented. It was derived from 47 inventories of preserved and undevelo... A checklist of the macrolichens (foliose, fruticose & squamulose) of Barluk Mountain National Nature Reserve located in northwestern China is presented. It was derived from 47 inventories of preserved and undeveloped areas which yielded more than 670 collections containing 102 taxa (99 species, 1 subspecies, 2 varieties). Eight species were found that were new to Xinjiang, China. Twenty-eight species and 2 varieties were found on rock, 31 species on bark of deciduous and coniferous trees, 26 species on soil and 14 species and 1 subspecies over mosses. Foliose lichens were dominant with 76 species, followed by 16 species of squamulose lichens and 7 species of fruticose lichens. 展开更多
关键词 BIODIVERSITY Mountain Ecosystems Monitoring Climate Change Nature Conservation
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Collaboration between Earth Sciences and Archaeology: Technology, resources, and synthesis
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作者 Ruiliang LIU A Mark POLLARD 《Science China Earth Sciences》 SCIE EI CAS CSCD 2022年第11期2033-2036,共4页
1.Introduction of the special topic The collaboration between archaeology and science can be tracked back to more than two hundred years ago and has undoubtedly led to fruitful results(for review see Pollard et al.,20... 1.Introduction of the special topic The collaboration between archaeology and science can be tracked back to more than two hundred years ago and has undoubtedly led to fruitful results(for review see Pollard et al.,2007:5).One great example is attributed to the invention of radiocarbon dating by Willard F.Libby,with the help of ancient Egyptian samples,which ultimately granted him a Nobel Prize in 1960. 展开更多
关键词 SYNTHESIS attributed DOUBT
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Environmental Changes and Human Impacts on Landscapes near Medieval Steklyanukha-2 Fortress in Russia from Early Iron Age to Modern Times
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作者 RAZJIGAEVA Nadezhda GANZEY Larisa +4 位作者 KORNYUSHENKO Tatiana GREBENNIKOVA Tatiana KUDRYAVTSEVA Ekaterina PISKAREVA Yana PROKOPETS Stanislav 《Chinese Geographical Science》 SCIE CSCD 2023年第1期69-84,共16页
The development of landscapes in one of the most populated river basins of the southern Russian Far East was studied using pollen and diatom data. The study sites were a multi-layered mountain fortress, Steklyanukha-2... The development of landscapes in one of the most populated river basins of the southern Russian Far East was studied using pollen and diatom data. The study sites were a multi-layered mountain fortress, Steklyanukha-2, and an Upper Holocene high floodplain sequence of the Steklyanukha River. Buried soil from the fluvial section acts as an environmental archive of the time in which people from the Yankovskaya archeological cultures settled in the river basin. The soil was formed under conditions of decreasing water supply in the valley and prolonged droughts. Findings of pollen Fagopyrum and Urtica signal economic activity in the Early Iron Age.Floodplain lake sediments accumulated from 1.6 to 0.5 kyr, when the valley was actively developed during the Middle Ages. There are signals of the development of secondary birch and oak forests. In the cultural layer of the fortress and lake sediments formed in the Middle Ages, Ambrosia and Xanthium pollens were found and are reliable evidence of agricultural activity in the valley. The pollens of plants typically seen in human-disturbed areas were also found. Indirect evidence of human activity includes non-pollen palynomorphs.The study of diatoms in a depression near a rampart confirmed the archaeologists' assumption that it was used as a water reserve. Pollen spectra from surface soils reflect agricultural activity in the river basin since the second half of the 19th century. The largest amount of pollen of alien and synanthropic plants and weeds, as well as spores of pathogenic fungi and fire indicators, were found here. 展开更多
关键词 ancient agriculture mountain fortress humidity changes POLLEN DIATOMS
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Handicraft Technique for Making Liansi Paper
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作者 Mourun Li 《Paper And Biomaterials》 CAS 2023年第3期47-57,共11页
Liansi paper is a kind of traditional handmade bamboo paper produced in Yanshan County,Jiangxi Province,whose handicraft technique is listed as a national intangible cultural heritage protection project.This study con... Liansi paper is a kind of traditional handmade bamboo paper produced in Yanshan County,Jiangxi Province,whose handicraft technique is listed as a national intangible cultural heritage protection project.This study conducted a field survey in Shangrao,and the main survey areas included Guangxin District and the Hekou,Goose Lake,Gexian Mountain,Tianzhu Mountain,Chenfang,and Shitang townships.Field investigators communicated with a group of intangible cultural heritage inheritors,and with their assistance,clarified the steps and processes involved in the production of Liansi paper.The handicraft technique of Liansi paper consists of five steps:chopping bamboo to make bamboo filaments,steaming bamboo filaments to make bamboo pulp,interweaving fibers into wet paper,drying wet paper,and package processing.A total of 13 processes are involved:chopping bamboo,fermentation,making bamboo filaments,soaking bamboo filaments,steaming bamboo filaments,natural bleaching,pounding bamboo filaments to make bamboo pulp,stirring pulp,adding plant mucilage,interweaving bamboo fibers into wet paper,pressing paper,drying wet paper,and package processing. 展开更多
关键词 Liansi paper bamboo paper handicraft technique pulp and paper
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Transmutation of Cai Lun’s Image
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作者 Yuqi Zou Zijun Zhu +2 位作者 Tingting Li Yuewei Zhu Biao Chen 《Paper And Biomaterials》 CAS 2023年第4期80-85,共6页
The earliest description of Cai Lun is that of an inventor of papermaking,which is included in historical books such as Dong Guan Han Ji and The Book of the Later Han;later,in his hometown,he was also inked by scholar... The earliest description of Cai Lun is that of an inventor of papermaking,which is included in historical books such as Dong Guan Han Ji and The Book of the Later Han;later,in his hometown,he was also inked by scholars because of some monuments about him,or the authors used his experience to express their own emotions.Recently,Cai Lun’s image has been clarified in textbooks,literary works,and urban civilization construction and is no longer considered merely a pioneer of papermaking.The development of his historical and literary image derives not only from the need for academic research but also the need to establish the Chinese nationalism and patriotism and promote traditional culture. 展开更多
关键词 Cai Lun PAPERMAKING industrial development personal image
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Climate and fire drivers of forest composition and openness in the Changbai Mountains since the Late Glacial
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作者 Meng Meng Sandy P.Harrison +5 位作者 Dongmei Jie Nannan Li Baojian Liu Dehui Li Guizai Gao Honghao Niu 《Forest Ecosystems》 SCIE CSCD 2023年第4期448-458,共11页
Ongoing climate changes have a direct impact on forest growth;they also affect natural fire regimes,with further implications for forest composition.Understanding of how these will affect forests on decadal-to-centenn... Ongoing climate changes have a direct impact on forest growth;they also affect natural fire regimes,with further implications for forest composition.Understanding of how these will affect forests on decadal-to-centennial timescales is limited.Here we use reconstructions of past vegetation,fire regimes and climate during the Holocene to examine the relative importance of changes in climate and fire regimes for the abundance of key tree species in northeastern China.We reconstructed vegetation changes and fire regimes based on pollen and charcoal records from Gushantun peatland.We then used generalized linear modelling to investigate the impact of reconstructed changes in summer temperature,annual precipitation,background levels of fire,fire frequency and fire magnitude to identify the drivers of decadal-to-centennial changes in forest openness and composition.Changes in climate and fire regimes have independent impacts on the abundance of the key tree taxa.Climate variables are generally more important than fire variables in determining the abundance of individual taxa.Precipitation is the only determinant of forest openness,but summer temperature is more important than precipitation for individual tree taxa with warmer summers causing a decrease in cold-tolerant conifers and an increase in warmth-demanding broadleaved trees.Both background level and fire frequency have negative relationships with the abundance of most tree taxa;only Pinus increases as fire frequency increases.The magnitude of individual fires does not have a significant impact on species abundance on this timescale.Both climate and fire regime characteristics must be considered to understand changes in forest composition on the decadal-to-centennial timescale.There are differences,both in sign and magnitude,in the response of individual tree species to individual drivers. 展开更多
关键词 Forest composition Climate change Fire regime Fire frequency Changbai Mountains HOLOCENE Generalized linear model
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禹州市煤矿区周边土壤和农作物重金属污染状况及健康风险评价 被引量:40
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作者 张成丽 张伟平 +7 位作者 程红丹 任少云 刘传文 李涛 楚小梅 郭志永 马建华 ZHANG Chaosheng 《环境化学》 CAS CSCD 北大核心 2019年第4期805-812,共8页
为全面了解河南省禹州市煤矿周边土壤和农作物中的重金属污染现状.对禹州市的某3个典型矿区(下文称为A、B和C矿区)周围土壤和主要谷类农作物(玉米和小麦)进行了调研和采样分析,并采用电感耦合等离子体质谱仪(ICP-MS)测定其重金属含量,... 为全面了解河南省禹州市煤矿周边土壤和农作物中的重金属污染现状.对禹州市的某3个典型矿区(下文称为A、B和C矿区)周围土壤和主要谷类农作物(玉米和小麦)进行了调研和采样分析,并采用电感耦合等离子体质谱仪(ICP-MS)测定其重金属含量,同时通过单因子指数法和内梅罗综合指数法评价了煤矿周围土壤的污染状况,并利用MMSOILS风险评价模型评价了食用当地谷类农作物对成人和儿童造成的重金属健康风险.结果表明:研究区土壤受到了重金属不同程度的污染,污染程度排序:小麦地>玉米地,且就单个重金属污染程度来说, Cd> Cu> Co> Ni> Zn> Cr;内梅罗综合污染指数分析结果表明,玉米地的污染程度为安全,小麦地的污染程度为重污染,均以Cd对污染指数P_(综合)值的贡献最大;研究区农作物玉米籽粒中Cr、Co、Ni、Cu、Zn和Cd的平均含量分别为25.03、0.54、2.87、21.52、118.68、1.97 mg·kg^(-1);小麦籽粒中Cr、Co、Ni、Cu、Zn和Cd的平均含量分别为1.04、0.11、1.17、9.55、61.51、0.06 mg·kg^(-1).Cr、Co、Ni、Cu、Zn和Cd富集系数大小的顺序均为玉米>小麦;健康风险评价表明,研究区农作物籽粒中存在高重金属污染风险,尤其以Cd最为明显,食用当地谷类农作物对人体造成健康风险的顺序依次为Co> Cd> Cu> Zn> Ni> Cr,其中Co、Cd对成人风险较高,Co、Cu、Zn、Cd对儿童风险较高,对儿童造成的健康风险要明显高于成人;土壤重金属含量与谷类农作物可食部分重金属含量间无明显相关性. 展开更多
关键词 土壤 谷类农作物 重金属 健康风险 污染特征
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禹州市废旧煤矿周边土壤重金属总量及有效态分析与评价 被引量:15
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作者 张成丽 王阳 +9 位作者 白银雪 刘鑫 叶梦雨 何清宇 张伟平 钱静 任少云 马建华 ZHANG Chao-sheng 郭志永 《安全与环境学报》 CAS CSCD 北大核心 2019年第6期2183-2191,共9页
为研究煤矿周边土壤重金属总量及有效态污染特征,以河南省禹州市废旧煤矿区为研究对象,采用硝酸-氢氟酸-高氯酸消解法测定重金属总量和DTPA浸提法测定有效态,分析重金属有效态质量比与重金属总量、土壤理化性质的相关性,运用内梅罗综合... 为研究煤矿周边土壤重金属总量及有效态污染特征,以河南省禹州市废旧煤矿区为研究对象,采用硝酸-氢氟酸-高氯酸消解法测定重金属总量和DTPA浸提法测定有效态,分析重金属有效态质量比与重金属总量、土壤理化性质的相关性,运用内梅罗综合污染指数法、潜在生态风险指数法评价煤矿区周边土壤的重金属污染特征。结果表明,Ni、Cu、Zn、Cd和Pb重金属总量均高于河南省潮土背景值,但均在国家土壤环境二级标准阈值范围之内;土壤有效态Ni、Cu、Zn、Cd和Pb平均质量比分别为0. 19 mg/kg、1. 23mg/kg、3. 36 mg/kg、0. 03 mg/kg和1. 71 mg/kg,其生物有效性系数分别为0. 40%、1. 28%、2. 12%、0. 83%和4. 11%,且相关性分析表明土壤Ni、Cu、Zn、Cd和Pb有效态的质量比受pH值、有机质、粒径、重金属形态及总量高低的影响。研究区土壤重金属Cd、Ni、Cu、Zn和Pb有不同程度累积,均达到了污染水平;区域重金属内梅罗综合污染指数已达到重污染;基于潜在生态风险评价,重金属总量和有效态潜在生态风险危害最高的重金属均为Cd,总量和有效态RI分别为193. 20、188. 72。 展开更多
关键词 环境工程学 煤矿周边土壤 重金属 有效态 相关性 风险评价
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火山灰的提取及测试技术 被引量:8
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作者 隋淑珍 刘嘉麒 +3 位作者 郭正府 Valerie A.HALL Chris S.M.TURNEY 王文远 《地学前缘》 EI CAS CSCD 2003年第1期111-116,共6页
同一次火山爆发产生的火山灰 ,能在广阔的区域内形成等时标志层 ,成为地层定年和对比的极有价值的工具。文中介绍了提取肉眼不可见火山灰的 4种方法 :烧失法、稀碱法、重液浮选法和酸化法 ,还介绍了火山玻璃的显微镜下识别技术及电子探... 同一次火山爆发产生的火山灰 ,能在广阔的区域内形成等时标志层 ,成为地层定年和对比的极有价值的工具。文中介绍了提取肉眼不可见火山灰的 4种方法 :烧失法、稀碱法、重液浮选法和酸化法 ,还介绍了火山玻璃的显微镜下识别技术及电子探针测试技术。 展开更多
关键词 火山灰 火山爆发 等时标志层 地层定年 烧失法 稀碱法 重液浮选法 酸化法 电子探针
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