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Epidemiological survey of cystic echinococcosis in southwest China:From the Qinghai-Tibet plateau to the area of Yunnan 被引量:1
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作者 Jin-Rong Zi Dan Xiao +8 位作者 Jia Peng Fang-Wei Wu Jian-Xiong Li Xin-Liu Yan Zheng-Qing Wang Xuan Cai Qian Xu Ben-Fu Li Ya-Ming Yang 《World Journal of Hepatology》 2024年第2期229-240,共12页
BACKGROUND Echinococcosis is prevalent in 9 provinces in Western and Northern China.An epidemiological survey of echinococcosis in 2012 and 2016 showed cases of echinococcosis in Yunnan Province.AIM To understand the ... BACKGROUND Echinococcosis is prevalent in 9 provinces in Western and Northern China.An epidemiological survey of echinococcosis in 2012 and 2016 showed cases of echinococcosis in Yunnan Province.AIM To understand the spatial distribution and epidemiological characteristics of echinococcosis in Yunnan for the prevention and control of echinococcosis and to reduce the risk of infection in Yunnan Province.METHODS Based on the China Information System for Disease Control and Prevention(CISDCP),echinococcosis cases reported from 36 hospitals and 34 Centers for Disease Control were investigated and epidemiologically analyzed from 2021 to 2022.The exclusion criteria included suspected cases,same case only counted once and cases not from Yunnan.A total of 705 cases were investigated,of which 397 cases were suitable for statistical analysis.In these 397 cases,epidemiological investigation was tracked in 187 cases.All data were inputted using double entry in the Excel database,with error correction by double-entry comparison.The data on echinococcosis cases in Yunnan Province were analyzed by ArcGIS 10.1 software to generate a density map of echinococcosis distribution.All statistical analyses were conducted using SPSS 17.0,including the chi-square test,linear regression test and logistic univariate and multivariate regression analyses.RESULTS A total of 397 cases were found in 89 counties in Yunnan Province.The number of cases in the top three prefectures were Dali(38.1%),Diqing(10.1%),and Kunming(8.3%),and the top five counties were Jianchuan(9.1%),Shangri La(8.3%),Eryuan(7.6%),Heqing(6.9%),and Dali Districts(5.0%).There were significant differences between the different areas.The case reporting rate by CISDCP(33.8%)was low;the first case was reported by CISDCP in 2002,and the highest number of cases was 50(2017).Confirmed and clinical cases accounted for 62.5%and 37.5%,respectively.However,90.9%of the cases of hydatid disease were reported by the hospital system,and only 9.1%of the cases of hydatid disease were found in the community through active screening.The difference between the two methods of case detection was statistically significant.Most of the cases of echinococcosis were found in farmers/herdsmen(75.1%)and students(9.1%).In addition,Han(43.6%)and Bai(26.2%)had a higher incidence of infection than other nationalities,and the liver(87.7%)and lung(6.8%)were the most common sites of cyst formation.Among the analyzed cases,187 were epidemiologically analyzed and the clinical symptoms were not obvious in the early stage in 47.1%of cases.The results of logistic regression analysis showed that the age group,education level,presence of dogs in the family(either previously or currently),and handwashing(occasionally or not)were factors related to echinococcosis infection.55.6%of cases were in endemic areas,and 44.4%of cases were in non-endemic areas.Among 83 cases in non-endemic areas,only 4 cases had been to endemic areas and had a history of living,working,travelling,or hunting in echinococcosis epidemic areas.CONCLUSION Cases of echinococcosis were reported throughout the entire Yunnan province,with the majority distributed in Western Yunnan,suggesting that echinococcosis control should be strengthened in this area.We suggest that an epidemiological investigation should be carried out in the future,based on the clues from newly discovered cases in hospitals or from the CISDCP.The newly discovered cases in the hospital provided clues to comprehensively determine the location of cases and where epidemic spot investigation should be conducted. 展开更多
关键词 ECHINOCOCCOSIS CASES Epidemiological analysis yunnan province
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A Brief Discussion on the Development of the Silk-Weaving Industry Along the “Southern Silk Road” in Yunnan 被引量:1
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作者 Lin Kaiqiang 《Contemporary Social Sciences》 2024年第1期18-33,共16页
Ancient Yunnan was one of the most significant regions along China’s ancient“Southern Silk Road.”During the Nanzhao period(738–902)of the late Tang Dynasty,Yunnan’s silk-weaving industry underwent a qualitative l... Ancient Yunnan was one of the most significant regions along China’s ancient“Southern Silk Road.”During the Nanzhao period(738–902)of the late Tang Dynasty,Yunnan’s silk-weaving industry underwent a qualitative leap as skilled silk craftsmen from the Bashu area migrated to Yunnan and introduced mulberry planting,silkworm breeding,and advanced silk-weaving techniques from Sichuan to the region.Consequently,people in Yunnan gradually acquired expertise in brocade weaving and embroidery.Many even mastered complex silk-weaving techniques.The development and progress of the silk-weaving industry in the ancient Yunnan region were intricately linked to the economic function and value of silk as both a commodity and currency along the“Southern Silk Road.”The local government in ancient Yunnan was greatly motivated by the economic interests brought by the development of silk-related industries and recognized the significance of developing the local silk industry.They even initiated a campaign to capture skilled silk craftsmen from Sichuan,aiming to foster the growth of the silk-weaving industry in Yunnan.After years of dedicated efforts from the local government in ancient Yunnan,the region emerged as a significant hub for silk production along China’s ancient“Southern Silk Road.”Despite the devastation caused by the wars in other parts of the country,Yunnan’s silk industry continued to thrive and provide ample silk products to sustain trade along this renowned route.In the contemporary era,amidst the decline of the silk-weaving industry in eastern China,Yunnan has proposed an industrial development strategy known as“relocating the silk-weaving industry from east to west.”This involves introducing advanced silk production techniques from the eastern regions into Yunnan to enhance and enrich its local silk industry,thereby establishing it as a traditional national sector and securing a competitive position within the global silk market.The historical experience of Yunnan’s silk industry demonstrated that economic development opportunities can only be seized through proactive endeavors rather than passive anticipation.The modern Yunnan silk industry,which upholds its historical traditions,continues to actively engage in international high-end technical cooperation,thus ensuring the enduring vitality of the ancient“Southern Silk Road.” 展开更多
关键词 Southern Silk Road Bashu area yunnan silk-weaving technique
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Geology and Geochemistry of K-feldspar Veins in Lamprophyre at the Zhenyuan Gold Deposit,Yunnan,Southwest China:Implications for Gold Mineralization
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作者 ZHANG Huichao CHAI Peng +2 位作者 ZHANG Hongrui ZHOU Limin HOU Zengqian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期104-116,共13页
Lamprophyres typically appear in hydrothermal gold deposits.The relationship between lamprophyres and gold deposits is investigated widely.Some researchers suggest that the emplacement of lamprophyres triggers gold mi... Lamprophyres typically appear in hydrothermal gold deposits.The relationship between lamprophyres and gold deposits is investigated widely.Some researchers suggest that the emplacement of lamprophyres triggers gold mineralization,whereas others hypothesize that the formation of lamprophyres increases the fertility of mantle sources and ore-forming fluids.K-feldspar veins,with ages between those of lamprophyres and gold deposits,appear in lamprophyres in Zhenyuan.Therefore,K-feldspar veins are ideal for investigating the relationship between lamprophyres and gold deposits.Phlogopite in K-feldspar veins has lower Mg#,Ni,and Cr contents and higher TiO2,Li,Ba,Sr,Sc,Zr,Nb,and Cs contents than phlogopite in lamprophyres.The in-situ Sr isotopic values of apatites(0.7063–0.7066)in K-feldspar veins are within the range for apatites(0.7064–0.7078)from lamprophyres.High large-ion lithophile element concentrations and low Nb and Ta concentrations in phlogopite from lamprophyres,in addition to high(87Sr/86Sr)i values of apatite(0.7064–0.7078),indicate that the magma parental to these phlogopite and apatite crystals is derived from an enriched mantle.Kfeldspar veins are genetically correlated with lamprophyres,whereas sulfide mineral assemblage and trace element compositions of pyrite in K-feldspar veins suggest that K-feldspar veins in lamprophyres are not directly related to gold mineralization of the Zhenyuan deposit. 展开更多
关键词 LAMPROPHYRE K-feldspar vein apatite Sr isotope gold Zhenyuan deposit yunnan
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Reanalysis on the Spectral Characteristics and Materials of Jade Jue Unearthed from Lijiashan Ancient Tomb in Yunnan Province, China
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作者 Ting Fang Jifu Liu Mingxing Yang 《宝石和宝石学杂志(中英文)》 CAS 2024年第2期48-55,共8页
Jade ware Jue is one of the most fashionable ornament in ancient China from the Neolithic Age to the Han Dynasty.In this study,the remnants of jade ware Jue,from Lijiashan ancient tomb group have been tested and analy... Jade ware Jue is one of the most fashionable ornament in ancient China from the Neolithic Age to the Han Dynasty.In this study,the remnants of jade ware Jue,from Lijiashan ancient tomb group have been tested and analyzed respectively.The samples through a light etch surface showing glass luster and those with a severe etch surface showing earthen luster.With the aid of X-ray fluorescence Spectrometer(X-ray Fluorescence)test and X-ray diffraction(XRD)detection,the results show that tremolite is not the main mineral of the sample.The main components of the tested samples with light erosion are antigorite and talc,although the main components of the samples with severe erosion are calcite containing calcium carbonate barium.Furthermore,the research on jade ware Jue in Yunnan culture has not only contributed to our further understanding of the jade objects from Yunnan culture and the variety of jade material located in the Yunnan Province.It also provides a basis for the trace of the history and culture through the distribution and evolution of burial hierarchy laws.At the same time,the microscopic observation of the tested samples manifested a residual trace of“string”at the perforation,which has played a critical role in restoring the wearing of jade ware Jue from the tombs of the ancient Yunnan State and the handicraft skills at that time. 展开更多
关键词 Dian culture jade Jue corroded ancient jade XRD erosion mechanism yunnan China
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Latest Neogene Paleoclimate Variation in Yunnan,Southwest China,Revealed by Fossil Leaf Physiognomy 被引量:1
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作者 DAI Jing CHEN Weizhao +1 位作者 HUANG Liang ZHANG Yi’nan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第4期1268-1281,共14页
Yunnan Province,located in the southeastern margin of the Tibetan Plateau,can provide important information on how climate change was influenced by global cooling.However,its variation patterns in temperature and prec... Yunnan Province,located in the southeastern margin of the Tibetan Plateau,can provide important information on how climate change was influenced by global cooling.However,its variation patterns in temperature and precipitation during the latest Neogene are not well-understood.Based on the 357 specimens assigned to 31 morphotypes of plant fossils from the upper Pliocene Ciying Formation in Yiliang County,Yunnan Province,Southwest China,paleoclimate was estimated by Leaf Margin Analysis and Climate Leaf Analysis Multivariate Program.Compared to the present climate,the mean annual temperature and coldest month temperature have not changed significantly since the late Pliocene,whereas the warmest month temperature has decreased significantly.All precipitation-related parameters have decreased,particularly winter precipitation.Combined with the climatic data of the same period in other areas of Yunnan,the western and eastern Yunnan has shown a similar pattern in temperature variation since the late Pliocene except for central Yunnan;whereas the variation in precipitation does not follow a common law except for a consistent decrease in winter precipitation.Our study reinforced the fact that under the background of global cooling and intensified monsoon systems,different areas of Yunnan exhibit different climatic responses to these changes because of their topographic heterogeneities. 展开更多
关键词 plant fossil paleoclimate reconstruction MONSOON PLIOCENE yunnan
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A New Species of the Genus Hebius Thompson,1913(Serpentes:Natricidae)from Yunnan,China 被引量:1
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作者 Shun MA Shengchao SHI +1 位作者 Budian AYI Jianping JIANG 《Asian Herpetological Research》 SCIE CSCD 2023年第3期212-226,共15页
A new keelback snake of the genus Hebius,H.jingdongensis sp.nov.,is reported from Jingdong in Yunnan,China based on a combination of molecular and morphological evidence.Although closest to H.khasiensis and H.boulenge... A new keelback snake of the genus Hebius,H.jingdongensis sp.nov.,is reported from Jingdong in Yunnan,China based on a combination of molecular and morphological evidence.Although closest to H.khasiensis and H.boulengeri phylogenetically,this new species is genetically distinct amongst congeners with the mitochondrial Cyt b uncorrected p-distance ranging from 9.5%(vs.H.octolineatus)to 14.8%(vs.H.andreae).In addition,this new species can be distinguished from its congeners by a combination of the following morphological characters:(1)body cylindrical,tail relatively short,TaL/TL 0.235–0.243;(2)dorsal scale rows 19-19-17;(3)ventrals 163–166,cloacal plate divided,subcaudals 71–74 pairs;(4)supralabials 8,the first two contact with the nasals;(5)infralabials 9 or 10,preocular 1,postoculars 3;(6)body dorsum sandy beige with the sides yellowish-brown decorated with two brick-red stripes on the dorsolateral scale rows in life;(7)sutures between the labials brick-red in life and taupe in preservative;(8)ventral light yellow with the outer part of each scale brick-red in life;(9)ventrolateral stripes present. 展开更多
关键词 Hebius jingdongensis sp.nov. molecular phylogeny morphology taxonomy yunnan province
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New and interesting diatoms from the Shimen Wetwalls,Yunnan Province,China.Ⅱ.The diatom genus Nupela Vyverman&Compère(Bacillariophyceae)
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作者 Qi LIU Xi LUO +1 位作者 Shulian XIE John Patrick KOCIOLEK 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期327-341,共15页
We detailed the valve morphology of five new species of diatom genus Nupela from wetwall communities in Yunnan Province,China,with light and scanning electron microscope.The five new species demonstrate great variabil... We detailed the valve morphology of five new species of diatom genus Nupela from wetwall communities in Yunnan Province,China,with light and scanning electron microscope.The five new species demonstrate great variability within the genus,as three of them are biraphid and two are monoraphid.In addition,variation was noted in the structure of internal proximal raphe ends,with some species having anchor-shaped ends and other species have hooked ends.The genus Nupela has grown considerably in 30years since it was first proposed,going from a monotypic genus to over 85 taxa.Diagnosis of the genus is based on the presence of an external covering over the areolae.We discussed the systematic placement of Nupela within the naviculoid diatoms.Yunnan Province appears to harbor many endemic diatom taxa,and many regions of the province have yet to be studied. 展开更多
关键词 Nupela scanning electron microscope(SEM) yunnan new species morphology China BACILLARIOPHYCEAE
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Inferring Human-elephant Coexistence Based on Characteristics of Human-elephant Interactions in Nangunhe of Yunnan,China
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作者 WANG Jiahui CHEN Ying +2 位作者 SUN Yakuan LYU Zhuoluo SHI Kun 《Chinese Geographical Science》 SCIE CSCD 2023年第2期363-376,共14页
Human-wildlife conflict(HWC)negatively impacts both humans and wildlife.Attitudes of local residents have been critical in promoting wildlife conservation.It is therefore necessary to understand the characteristics of... Human-wildlife conflict(HWC)negatively impacts both humans and wildlife.Attitudes of local residents have been critical in promoting wildlife conservation.It is therefore necessary to understand the characteristics of HWC and identify influential factors on attitudes towards conservation to implement conservation strategies efficiently.This research focused on features of human-elephant interactions,while attitudes and values regarding the small population of Asian elephants(Elephas maximus)in Nangunhe National Nature Reserve(NNR),Yunnan,China.The total of 327 valid questionnaires were gathered around the area where Asian elephants were distributed.Logistic regression models were employed to analyze the correlations among five predictor variables(‘Area’,‘Family size’,‘Annual income’,‘Quantity of family members in non-primary industries’and‘Experiencing loss or not’)and three response variables(‘Attitude towards elephants’,‘Perception of the values of elephants’and‘Attitude towards tourism development’).The study area was densely forested with tea plants,rubber trees,corns and sugarcane.There,25.99%of respondents reported the experience of human-elephant conflict(HEC),with crop raiding and cash crop damages being the major conflict types.To demonstrate respect for elephants and to mitigate HEC,a unique custom called‘Giving tribute to elephants’was developed long ago.Respondents’township with an official annual festival of‘Giving Tribute to Elephants’(odds ratio(OR)=2.75,P=1.73×10^(-6))and higher annual income(OR=2.09,P=5.45×10^(-5))significantly contributed to forming a more positive attitude towards elephants,whereas HEC itself have contributed to a more negative attitude(OR=0.50,P=3.29×10^(-3)).Therefore,we propose that:1)reducing human-elephant conflict by testing multiple mitigation measures and adopting the most effective one of them;2)enhancing local livelihoods through the development of ecological products and ecotourism;and 3)preserving and developing the Wa culture in this region.The study area deserves more attention and further research to explore and obtain endorsement from the public to achieve coexistence between human and wildlife. 展开更多
关键词 Asian elephant(Elephas maximus) Wa people human-elephant conflict COEXISTENCE Nangunhe National Nature Reserve yunnan China
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2017—2021年云南省猪瘟病原学和血清学监测情况分析 被引量:3
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作者 胡媛媛 张懿 +9 位作者 赵屹钦 曾邦权 王俊美 杜润 赵珍 张然 何依蓉 陈红艳 张文东 赵焕云 《中国动物检疫》 CAS 2024年第1期11-15,共5页
为全面了解2017—2021年云南省猪瘟(CSF)流行及免疫状况,预估疫病流行和发生风险,采集病原学样品63 224份、血清学样品146 547份,进行CSF病原和血清抗体监测。结果显示:2017—2021年云南省CSF免疫抗体合格率分别为82.94%、81.47%、80.79... 为全面了解2017—2021年云南省猪瘟(CSF)流行及免疫状况,预估疫病流行和发生风险,采集病原学样品63 224份、血清学样品146 547份,进行CSF病原和血清抗体监测。结果显示:2017—2021年云南省CSF免疫抗体合格率分别为82.94%、81.47%、80.79%、80.24%、82.53%,规模场合格率略高于散养户,但差异不显著(P>0.05);CSF病原核酸阳性率分别为0.52%、0.74%、1.10%、1.02%、2.42%,散养户、屠宰场阳性率高于规模场。结果表明:自2017年CSF退出强制免疫后,云南省CSF免疫抗体合格率均达到国家标准,但病原阳性率整体呈上升趋势,且分布范围广,免疫密度低和抗体合格率低的散养户发生CSF的风险较高,提示应对其加强监测和免疫。 展开更多
关键词 猪瘟 病原学 血清抗体 监测 云南省
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云南梨地方品种果实表型性状多样性分析 被引量:1
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作者 梁艳萍 董菲 +3 位作者 黄文静 陈瑶 丁仁展 李坤明 《果树学报》 CSCD 北大核心 2024年第1期41-51,共11页
【目的】深入了解云南梨地方品种果实表型性状的变异特点和多样性。【方法】以云南有代表性的61个梨地方品种为试验材料,对果实16个描述型性状和7个数量型性状进行变异类型和多样性分析,利用电子鼻技术检测果实香气并进行主成分分析。... 【目的】深入了解云南梨地方品种果实表型性状的变异特点和多样性。【方法】以云南有代表性的61个梨地方品种为试验材料,对果实16个描述型性状和7个数量型性状进行变异类型和多样性分析,利用电子鼻技术检测果实香气并进行主成分分析。【结果】云南梨地方品种果实的16个描述型性状变异类型丰富,其中果实形状和果实成熟期的变异类型最多。各描述型性状的多样性指数(H’)在0.45~1.88之间。19个梨地方品种果实在成熟时果皮分别着鲜红、淡红、粉红、暗红等不同盖色。7个数量型性状变异系数在11.25%~61.79%之间,单果质量的变异系数最高;多样性指数(H’)为1.676~2.080,果实纵径、果柄长度、可溶性固形物含量、果实横径、果形指数的多样性指数均大于2.0。电子鼻技术可以区分供试地方品种,WIW(硫化氢类)、W5S(氮氧化物)、W2W(芳香成分和有机硫化物)等3个传感器在模式识别中起主要作用。【结论】云南梨地方品种果实描述型性状变异类型丰富,数量型性状多样性指数较高。筛选出会泽火瓢梨等7个果皮着鲜红色的品种可作为红色梨选育的优异资源。电子鼻技术可以区分61个云南梨地方品种,可用作地方品种鉴定的辅助手段。 展开更多
关键词 云南 地方品种 果实性状 多样性 电子鼻
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云南省地质灾害气象风险预警技术改进及应用检验 被引量:1
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作者 杨竹云 许彦艳 +5 位作者 李华宏 杨迎冬 胡瑞峰 夏龙松 刘博文 魏蕾 《灾害学》 CSCD 北大核心 2024年第2期85-91,共7页
利用2014—2022年云南省地质灾害数据和气象降水资料,开展有效降水量致灾概率研究,并结合地质灾害易发因子,分区建立了新一代精细化地质灾害气象风险预警模型,并对模型性能开展了应用检验。结果表明:新建的地质灾害气象风险预警模型提... 利用2014—2022年云南省地质灾害数据和气象降水资料,开展有效降水量致灾概率研究,并结合地质灾害易发因子,分区建立了新一代精细化地质灾害气象风险预警模型,并对模型性能开展了应用检验。结果表明:新建的地质灾害气象风险预警模型提高了预警产品的时空分辨率和准确率,应用效果良好。模型能提前较好地反映出区域性强降水过程背景下的气象风险预警等级;对较难预报的局地强降水,也可以通过实时更新的监测预警产品给出风险加强的趋势,提前发出地质灾害气象风险预警信息;能直接客观反映出极端强降水背景下的气象风险高级别预警,起到较好的预警提示作用。 展开更多
关键词 云南 地质灾害 预警模型 致灾概率 检验
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Geological characterization and exploration potential of shale gas in the Carboniferous Jiusi Formation,northern Guizhou and Yunnan provinces,SW China
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作者 Weiming Feng Rong Li +3 位作者 Zhan Zhao Qian Yu Wei Liu Junfeng Cao 《Energy Geoscience》 2023年第3期169-181,共13页
Dark mudstones and shales of the Carboniferous Jiusi Formation are widely developed in northern Guizhou and Yunnan provinces, SW China. However, the distribution, reservoir characterization, and exploration potential ... Dark mudstones and shales of the Carboniferous Jiusi Formation are widely developed in northern Guizhou and Yunnan provinces, SW China. However, the distribution, reservoir characterization, and exploration potential of organic-rich shales in this area are yet to be quantified, thus limiting the prospect of shale gas in this area. This study investigates the basic geological conditions of Jiusi shale gas, using core data, well-logs, and some other test data, obtaining the following results. The organic-rich shales are mainly composed of deltaic-to-shallow-shelf deposits, with thickness ranging from 0 to 450 m, and above 350 m around the subsidence center. The organic matter is mainly type Ⅱ kerogen with TOC content of mostly 1%–2%, indicating a moderate maturity. The argillaceous shale reservoirs are indicative of strong heterogeneity, high clay minerals content, low porosity, low permeability, high specific surface area, and relatively developed secondary porosity. The gas-log anomaly intervals obtained from the survey wells have a cumulative thickness that is apparently greater than 200 m, and a few shale intervals showing high desorbed and adsorbed gas contents. Due to complex structures in the study area, conditions responsible for shale gas occurrence and trapping are generally moderate. However, areas having wide and gentle folds with moderate depth of burial reveals relatively favorable conditions of hydrocarbon traps. In contrast with typical marine-continental transitional shales, the Jiusi shale have better geological conditions for shale gas preservation. The analysis of the geological framework and hydrocarbon potential of Carboniferous Jiusi Formation provide more insight for the exploration of Carboniferous shale gas in southern China. 展开更多
关键词 Marine-continental tansitional fades 0rganic-nich shale Shale gas Exploration potential CARBONIFEROUS Northem border area between Guizhou and yunnan China
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气候变化和人类活动对云南省植被净初级生产力的影响 被引量:1
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作者 徐虹 程晋昕 +2 位作者 何雨芩 王玉尤婷 张茂松 《高原气象》 CSCD 北大核心 2024年第4期1064-1075,共12页
深入理解气候变化和人类活动对植被变化的驱动机制对于生态保护和可持续发展有重要的科学意义。本研究基于MOD17A3/NPP产品数据,采用线性趋势分析、Mann-Kendall显著性分析、Hurst指数和二阶偏相关分析,探讨云南省2001-2021年植被NPP的... 深入理解气候变化和人类活动对植被变化的驱动机制对于生态保护和可持续发展有重要的科学意义。本研究基于MOD17A3/NPP产品数据,采用线性趋势分析、Mann-Kendall显著性分析、Hurst指数和二阶偏相关分析,探讨云南省2001-2021年植被NPP的时空分布特征和未来持续性以及植被NPP与气候条件的关系。采用偏导趋势残差法分离和量化气候变化和人类活动对植被NPP的影响。结果发现,空间上,2001-2021年云南植被NPP年均值南高北低。不同植被类型NPP值(单位:gC∙m^(-2))从大到小依次为:林地(1106.7 gC∙m^(-2))、灌木(964.4 gC∙m^(-2))、农田(946.6 gC∙m^(-2))和草地(878.8 gC∙m^(-2))。植被NPP随海拔上升先增后降。(2)在研究时段内,植被NPP年均值为1020.8±30.7 gC∙m^(-2),最小值和最大值分别出现在2010年(950.0)和2019年(1062.1)。植被NPP呈显著增加趋势,增加率为2.1 gC∙m^(-2)∙a^(-1)(p<0.05),增加和显著增加的面积分别占研究区总面积70.0%和26.3%。不同植被类型NPP的增加率(单位:gC∙m^(-2)∙a^(-1))从大到小依次为:草地(4.1 gC∙m^(-2)∙a^(-1))、农田(3.5 gC∙m^(-2)∙a^(-1))、灌木(2.8 gC∙m^(-2)∙a^(-1))和林地(1.3 gC∙m^(-2)∙a^(-1))。Hurst指数均值为0.60,植被NPP未来变化趋势持续增加和由减少转为增加的面积占总面积的55.5%和9.3%,表明大部分地区植被NPP未来仍将持续增加。(3)2001-2021年云南省平均气温显著增加,降水和太阳辐射波动减少。大部分地区植被NPP与气温、降水和太阳辐射正相关,气温对植被NPP的影响大于降水和太阳辐射。(4)气候变化和人类活动对云南植被NPP变化的相对贡献率分别为27.1%和72.9%,正贡献的面积分别占研究区总面积的59.4%和64.6%,相对贡献率>60%的面积占比分别为12.7%和73.4%。大部分地区人类活动对植被NPP的影响大于气候变化。云南植被改善主要受气候变化和人类活动的共同作用的影响,植被退化则主要受人类活动主导和两者共同作用的影响,生态保护、恢复工程对云南植被改善有着显著的促进作用。 展开更多
关键词 云南 气候变化 人类活动 植被净初级生产力
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基于BEPS模型的云南省碳源/汇时空特征及其适用性分析 被引量:2
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作者 鲁韦坤 李蒙 +1 位作者 程晋昕 窦小东 《生态学报》 CAS CSCD 北大核心 2024年第4期1441-1455,共15页
净初级生产力(NPP)和净生态系统生产力(NEP)是估算陆地生态系统碳源/汇的重要指标,云南为我国碳汇的主要区域之一,开展云南NPP和NEP时空变化特征分析对科学评估陆地生态系统碳源/汇功能,以及开展碳排放交易具有重要意义。基于BEPS模型19... 净初级生产力(NPP)和净生态系统生产力(NEP)是估算陆地生态系统碳源/汇的重要指标,云南为我国碳汇的主要区域之一,开展云南NPP和NEP时空变化特征分析对科学评估陆地生态系统碳源/汇功能,以及开展碳排放交易具有重要意义。基于BEPS模型1981-2019年NPP和NEP产品,采用线性趋势分析、文献对比等方法,研究云南NPP和NEP时空变化特征及其在云南的适用性。结果表明:(1)1981-1999年云南NPP和NEP呈水平波动,2000年后云南NPP和NEP呈明显波动上升趋势,2000-2019年云南NPP高值区域主要分布在西部和南部,而NEP高值区则主要分布在东部和西部局部地区;(2)2000-2019年云南NPP和NEP除西北部部分地区为下降趋势外,其余大部地区为上升趋势;(3)云南NPP峰值出现在7、8月,谷值出现在2月,NEP峰值出现月份与NPP基本相同,但谷值出现月份较NPP滞后1-3个月,6-10月是云南碳汇的主要月份;(4)BEPS模型估算的NPP与目前广泛应用的CASA和遥感模型结果较为一致,时空变化特征与云南生态恢复措施和气候特征吻合,其估算的NEP与陆地生物圈模型(IBIS)模型和中国通量观测研究联盟(ChinaFLUX)碳水通量观测数据较为接近,时空变化大部地区与云南生态恢复措施和气候特征基本吻合,表明BEPS模型在云南具有较好的适用性。 展开更多
关键词 BEPS模型 NPP NEP 适用性 云南
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口岸经济高质量发展水平评价指标体系构建与测度——基于云南的实证研究 被引量:2
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作者 樊爱霞 潘海岚 王晓琴 《云南民族大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第2期115-128,共14页
加快口岸由“通道经济”转型为“产业经济”,是“一带一路”建设高质量发展的重要内容。基于高质量发展目标要求,对口岸经济高质量发展的内涵、特征进行学理性探讨,依托层次分析思想构建测度口岸经济高质量发展水平的评价指标体系。以... 加快口岸由“通道经济”转型为“产业经济”,是“一带一路”建设高质量发展的重要内容。基于高质量发展目标要求,对口岸经济高质量发展的内涵、特征进行学理性探讨,依托层次分析思想构建测度口岸经济高质量发展水平的评价指标体系。以边境口岸数量多、类型丰富的云南省为研究对象,选取2012—2021年数据,运用CRITIC权重法,对云南口岸经济高质量发展水平进行测度并分析其趋势特征。研究发现:样本期内云南口岸经济高质量发展水平总体呈现上升趋势,口岸经济协调发展和开放发展提升显著,创新发展有待加强,共享作用显现,绿色发展不平稳,岸城协调性不足。推动云南口岸经济高质量发展要转变发展理念,扩大高水平对外开放,建立岸岸、岸城协调发展机制,完善口岸基础设施,加强口岸开放发展能力,以此推进云南口岸现代化建设进程。 展开更多
关键词 口岸经济 高质量发展 指标体系 CRITIC权重法 云南
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滇中地区主要森林凋落物有效截留量及其影响因素 被引量:2
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作者 王平 李璐杉 +1 位作者 丁智强 李玉辉 《水土保持研究》 CSCD 北大核心 2024年第3期213-221,229,共10页
[目的]研究滇中地区主要森林类型凋落物有效截留量差异及其影响因素,为该地未来植被恢复和森林管理提供科学支撑。[方法]利用样方调查法、烘干法和浸泡法分析了昆明市双河—磨南德水源林自然保护区内的地带性次生常绿阔叶林(SF)、针阔... [目的]研究滇中地区主要森林类型凋落物有效截留量差异及其影响因素,为该地未来植被恢复和森林管理提供科学支撑。[方法]利用样方调查法、烘干法和浸泡法分析了昆明市双河—磨南德水源林自然保护区内的地带性次生常绿阔叶林(SF)、针阔混交林(TF)、旱冬瓜林(ACF)、华山松林(PA)、成熟云南松林(OPY)、幼龄云南松林(YPY)、银荆林(AD)7种主要森林类型凋落物未分解层(OL)和半分解层(OF)的有效截留量及其影响因素。[结果](1) 7种森林类型凋落物厚度为2.06~7.57 cm,其中OL层1.10~4.30 cm, OF层0.83~3.93 cm,凋落物层厚度排序为TF>ACF>PA>OPY>SF>AD>YPY,凋落物蓄积量为4.75~17.45 t/hm^(2),其中OL层占比为32.02%~62.48%,OF层占比为37.52%~67.98%,凋落物层蓄积量排序为TF>PA>SF>OPY>ACF>AD>YPY。(2)凋落物最大持水率为115.3%~170.7%,初始吸水速率为3.65~5.62 g/(g·h),凋落物持水率和浸水时间的关系可用对数函数y=aln(x)+b表示,吸水速率与浸水时间可用幂函数y=kt~n表示。(3)凋落物最大持水量为7.05~32.19 t/hm^(2),排序为PA>TF>SF>OPY>ACF>AD>YPY,有效截留量为5.45~25.34 t/hm^(2),以TF最高(25.34t/hm^(2)),PA(24.99 t/hm^(2))和SF(24.62 t/hm^(2))次之,YPY最低(5.45t/hm^(2)),影响有效截留量的场地特征主要为蓄积量、自然含水率、分解强度以及厚度,影响有效截留量的水动力过程主要是最大失水量、前6.0 h平均吸水速率和前2.0 h平均吸水速率。[结论]滇中地区未来植树造林应以针阔混交林为主,注重对地带性次生常绿阔叶林的保育,采取辅助自然更新的措施促进人工纯林向混交林演化,同时减少踩踏、收集凋落物等人类活动的干扰,从而增加森林生态系统凋落物的水源涵养能力。 展开更多
关键词 凋落物 主要森林类型 持水特性 有效截留量 滇中地区
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基于生计资本的农户可持续生计研究——以滇琼天然橡胶主产区为例 被引量:1
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作者 伍薇 刘锐金 +2 位作者 何长辉 杨琳 占达儒 《热带地理》 CSCD 北大核心 2024年第4期746-760,共15页
运用海南和云南橡胶主产区615个种植户的调查数据,测算了农户生计资本水平,设计了生计活动多样性指数和家庭收入多元化指数,通过多元线性回归模型和中介效应模型,探讨了生计资本配置对农户可持续生计的影响机制。研究发现:1)农户生计资... 运用海南和云南橡胶主产区615个种植户的调查数据,测算了农户生计资本水平,设计了生计活动多样性指数和家庭收入多元化指数,通过多元线性回归模型和中介效应模型,探讨了生计资本配置对农户可持续生计的影响机制。研究发现:1)农户生计资本积累有助于丰富农户家庭生计活动和收入来源结构,尤其是金融资本积累有助于提升农户生计活动多样性水平;不同生计资本结构对农户生计结果的影响存在地域性差异;自然资本禀赋对海南产区的收入多元化水平有显著推动作用,但在云南产区却可能存在“诅咒”效应。2)地域差异、生产决策和农户特性对可持续生计有重要影响。村庄所处的海拔高、距县城距离远对农户开展多样化生计构成挑战;割胶生产规律固化虽然可能会削弱农户其他生产经营活动,但由于其劳动力调整灵活性强,可更好地稳定家庭收入;土地细碎化具有多元化生计的效果,但不一定有收入效应;虽然贫困户身份可帮助农户获得相关政策的支持,但增强生计能力才是实现可持续生计的关键所在。3)生计资本对生计活动和家庭收入的影响存在中介效应。生计资本对生计多样性的促进作用,有52.70%是通过提高生计资本统筹能力实现的,家庭就业策略优化有助于增强生计资本对收入多元化的促进作用,中介效应达30.52%。最后,建议通过提高农户家庭生计资本统筹能力、加强生计能力建设、扩展就业信息渠道等来增强农户生计综合能力。 展开更多
关键词 天然橡胶 生计资本 生计多样性 收入多元化 中介效应 海南岛 云南省
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云南地区强震的超长时间平静异常及未来地震趋势研究
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作者 苏有锦 孙楠 +2 位作者 赵小艳 贺素歌 张潜 《地震学报》 CSCD 北大核心 2024年第2期242-256,共15页
从1996年丽江M_(S)7.0地震发生后至2023年8月,云南地区M≥6.7和M≥7.0地震出现了长达27.55 a的超长时间平静现象。本文从更大时空尺度上对该平静异常现象及其与青藏高原和川滇地块的强震活动之间的关系进行了分析和总结,并讨论了云南地... 从1996年丽江M_(S)7.0地震发生后至2023年8月,云南地区M≥6.7和M≥7.0地震出现了长达27.55 a的超长时间平静现象。本文从更大时空尺度上对该平静异常现象及其与青藏高原和川滇地块的强震活动之间的关系进行了分析和总结,并讨论了云南地区未来地震趋势。结果表明,1887年以来,云南地区5次M≥7.0地震平静期内其周边地震活动环境有很大差异性:第Ⅰ,第Ⅱ和第Ⅴ平静期出现在青藏高原M≥7.0地震活跃背景下(即云南地区平静,但青藏高原活跃),第Ⅲ和第Ⅳ平静期出现在青藏高原M≥7.0地震平静背景下(即云南地区平静,青藏高原也平静)。当前云南地区处于27.55 a超长时间平静期(即第Ⅴ平静期),其所处的周边地震活动环境与第Ⅰ和第Ⅱ平静期相似,据此推断,其后续地震趋势可能也与第Ⅰ和第Ⅱ活跃期相似,处于相对弱的活跃期。同时,未来较长时间青藏高原可能仍将处于M≥7.0地震活跃时段;2022年泸定M_(S)6.8地震后,川滇地块可能会进入M≥6.7地震活跃时段。 展开更多
关键词 云南地区 强震平静 青藏高原 川滇地块 强震活动状态
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黔北—滇东二叠纪锰矿主要成矿规律与成矿区带划分 被引量:1
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作者 刘志臣 周琦 +3 位作者 杨瑞东 杜远生 陈登 肖林 《矿产综合利用》 CAS 2024年第1期62-72,共11页
这是一篇地球科学领域的论文。锰矿为我国十分紧缺的战略矿产之一。黔北-滇东地区是我国二叠纪锰矿最典型的分布区,在全球晚古生代也较为少见,该区锰矿资源丰富,找矿潜力巨大,称为“遵义式锰矿”。研究表明,该区锰矿产于二叠纪茅口晚期... 这是一篇地球科学领域的论文。锰矿为我国十分紧缺的战略矿产之一。黔北-滇东地区是我国二叠纪锰矿最典型的分布区,在全球晚古生代也较为少见,该区锰矿资源丰富,找矿潜力巨大,称为“遵义式锰矿”。研究表明,该区锰矿产于二叠纪茅口晚期,分布严格受黔北裂谷盆地控制,锰矿在地堑盆地中心喷溢沉积成矿,在地垒区则无锰矿分布,矿体空间展布方向与盆地展布方向基本一致。其中,黔北遵义-黔西地区锰矿在空间上分布于盆地相区,并可分为中心相、过渡相、边缘相等三个锰矿相带,进一步指示了锰矿具体成矿位置,显示了锰矿受盆地中心控制非常明显的特点。在划分的遵义-宣威锰矿成矿带的基础上,详细划分出遵义-黔西锰矿成矿亚带中深溪—八里、龙坪—兴隆、团溪—尚稽、黔西4个锰矿矿集区,以及水城-宣威锰矿成矿亚带中水城—纳雍、格学2个锰矿矿集区。该研究成果对寻找黔北—滇东二叠纪隐伏锰矿床,开展成矿预测,具有重要的意义。 展开更多
关键词 地球科学 二叠纪锰矿 成矿规律 成矿区带 黔北—滇东
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云南省生态环境质量与生态修复区识别 被引量:1
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作者 杨雪 李益敏 +2 位作者 赵娟珍 蒋文学 李媛婷 《水土保持通报》 CSCD 北大核心 2024年第2期277-290,共14页
[目的]分析云南省生态环境时空变化,识别生态修复优先序,为该省低碳的可持续发展提供科学依据。[方法]基于遥感生态指数(RSEI)研究生态环境质量时空变化及空间相关性,与区域生态系统碳储量及生态保护红线结合识别云南省生态修复优先序。... [目的]分析云南省生态环境时空变化,识别生态修复优先序,为该省低碳的可持续发展提供科学依据。[方法]基于遥感生态指数(RSEI)研究生态环境质量时空变化及空间相关性,与区域生态系统碳储量及生态保护红线结合识别云南省生态修复优先序。[结果]①22 a间云南省RSEI均值呈S形变化趋势,分别以2005年和2011年作为上升和下降的拐点。②2000—2022年空间上生态环境质量均表现为“西高东低”的态势,西部地区生态环境质量较好,而中部城市群及东部喀斯特地区生态环境质量较差。③2000—2005年受退耕还林政策的影响生态环境质量变好。2005—2011年则因旱灾和建设用地的剧烈扩张导致生态环境质量大幅下降。2011—2016年是旱灾后恢复时段,除中部城市化快速发展地区外,其他地区生态环境质量在逐渐恢复。2016—2022年受国家政策的影响,生态环境质量进一步变好。④云南省生态环境质量在空间上表现出明显的空间全局与局部自相关。⑤2000—2022年云南省碳储量呈先增加后减少的趋势,22 a间总碳储量减少2.38×10^(7)t,在空间上总体表现为“南北高,中间低”的地带性分布特征。⑥云南省生态修复极优先区主要分布在北部及东部地区,约占总面积的18.08%,生态修复优先区及中等优先区则分布较为广泛,约占总面积的70.17%。生态修复一般优先区主要位于普洱市等地,约占总面积的11.76%。[结论]云南省2000—2022年生态环境质量在时空上均呈现一定规律,在此基础上进行生态修复区划分,因地制宜地治理生态环境,推进云南省生态及低碳的可持续发展。 展开更多
关键词 遥感生态指数 生态环境质量 生态修复区 云南省
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