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Effects of Different Land Use Patterns on Soil Microbial Quantity and Activity in Hongta District,Yuxi City 被引量:1
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作者 陈艳 刘家忠 何倩倩 《Agricultural Science & Technology》 CAS 2016年第11期2535-2538,共4页
[Objective] This study aimed to investigate the effects of different land use patterns on soil ecological environment. [Method] Total three representative land use patterns (corn field, cherry tree land, wood land) ... [Objective] This study aimed to investigate the effects of different land use patterns on soil ecological environment. [Method] Total three representative land use patterns (corn field, cherry tree land, wood land) were selected from Hongta District, Yuxi City, and under these three patterns, soil microbial quantity and activity were studied. [Result] Under the three land use patterns, soil microorganisms were domi- nated by bacteria; soil microbial quantity ranked as wood land's〉cheery tree land's〉 corn field's; and total microbial activity, catalase activity and urease activity all ranked as cherry tree land's〉wood land's〉corn field's. [Conclusion] Soil microbial activity and functions are related to farmland management measures, as well as land use pattern and soil nutrients. 展开更多
关键词 Land use pattern Total quantity of microorganisms Microbial activity Hongta District of yuxi City
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On the Plant Diversity and Ecosystem Construction in Yuxi City of Yunnan Province
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作者 马长乐 李靖 +1 位作者 刘迪 刘亮 《Journal of Landscape Research》 2009年第8期43-46,共4页
315 species(and cultivars) belonging to 235 genera of 104 families are recorded by investigation in the urban area of Yuxi City,Yunan Province.The investigated areas include urban parks,squares,street green belts,and ... 315 species(and cultivars) belonging to 235 genera of 104 families are recorded by investigation in the urban area of Yuxi City,Yunan Province.The investigated areas include urban parks,squares,street green belts,and accessory greenbelts of institutes.It is concluded that the urban plant diversity is inferior to that of natural forest community of the prefecture area.Strategies for urban ecosystem construction in Yuxi City are proposed based on the development goal of ecological garden city. 展开更多
关键词 yuxi CITY URBAN BIODIVERSITY INVESTIGATION
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Structural Geochemical Study of the Yuxi Fold-Thrust Belt in the Southern North China Plate 被引量:2
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作者 李文勇 夏斌 李东旭 《Journal of China University of Geosciences》 SCIE CSCD 2006年第2期95-102,共8页
The Yuxi (豫西) fold-thrust fracture belt is part of the gigantic fold-thrust fracture belt that extends NW in the southern North China plate. The contents of major elements of tectonites were analyzed by ICP-AES. T... The Yuxi (豫西) fold-thrust fracture belt is part of the gigantic fold-thrust fracture belt that extends NW in the southern North China plate. The contents of major elements of tectonites were analyzed by ICP-AES. The analysis of chemical compositions and new stress minerals indicates: extending from the surrounding country rocks to the center of the fracture belt, the Fe2O3 content gradually increases while the FeO content gradually decreases; regular increase, decrease or peak changes are shown for chemical compositions like SiO2, Al2O3, Fe2O3, MgO, CaO, FeO, loss on ignition, TIO:, K2O, Na2 O, etc.. New stress minerals are developed for the south branch and few for the north branch. The characteristics of chemical compositions and new stress minerals of the thrust fracture demonstrate that the fracture belt has undergone a process from a closed reducing environmental system to a relatively open. oxidizing environmental system, andcompressive fractures have resulted from compression in the late stages of evolution, and the dynamothermal metamorphism and thrusting intensities are different between the south and north branches of the belt, which is strong for the south branch but relatively weak for the north branch. 展开更多
关键词 structural geochemistry thrust fracture belt yuxi southern North China plate.
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The Cause and Weather Circulation Features of Chilling Damage in Yuxi 被引量:1
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作者 JIN Shao-hua ZHOU Hong +1 位作者 AI Yong-zhi CAI Ai-ping 《Meteorological and Environmental Research》 CAS 2011年第6期46-50,共5页
[Objective] The aim was to study the reasons of low temperature and characteristics of weather in Yuxi City.[Method] The reasons of low temperature in Yuxi City were expounded.The types of low temperature and their in... [Objective] The aim was to study the reasons of low temperature and characteristics of weather in Yuxi City.[Method] The reasons of low temperature in Yuxi City were expounded.The types of low temperature and their influences on agricultural crops were introduced.The route of cold air and the typical circulation characteristics of low temperature were analyzed.[Result] The low temperature in Yuxi City was formed because of the influence of its topography and climate.The low temperature and cold disaster included frost,low temperature in spring and autumn;the influencing path of cold air in Yuxi City had four paths:northeast,north,northwest and east path.The circulation characteristics of snowing included southerly trough,strong and cold air,and cold front shear;under the long-term control of cold advection of upper air and cold high pressure in the low layer,the radiation,cooling and temperature reducing were the main circulation characteristics of heavy frost;the circulation background of low temperature in August was conductive to the strong cold air intruding the upper air circulation of Yuxi City.The cold trough in the north and low pressure in the south influenced the circulation in Yuxi City.[Conclusion] The study provided reference for the weather report and relevant professionals. 展开更多
关键词 Chilling damage Circulation feature Cause analysis yuxi City China
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On Public Signs in Yuxi Normal University
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作者 李娜 《英语广场(学术研究)》 2011年第Z5期72-,74,共2页
With the opening of Chinese colleges and the frequent cultural communication among international colleges, Yuxi Normal University, as a local university, has developed very quickly. More and more public signs appear o... With the opening of Chinese colleges and the frequent cultural communication among international colleges, Yuxi Normal University, as a local university, has developed very quickly. More and more public signs appear on campus, both in Chinese and English. But owing to various causes, many non-standard translations can be seen everywhere. From the aspects of commonly applied functions of public signs in colleges, this thesis analyses some common non-standard translations in directing public signs, restricting public signs and calling public signs, and proposes some suggestions on standard translation. 展开更多
关键词 PUBLIC SIGNS TRANSLATION yuxi NORMAL UNIVERSITY
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Regional eco-environmental analysis of Yuxi River-Chaohu Lake
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作者 Yin ChengqingResearch Center for Eco-Environmental Sciences,Academia Sinica,Beijing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1989年第2期23-28,共6页
Yuxi River-Chaohu Lake water suffers greatly from the ecological problems of eutrophication, high turbidity, organic pollution, disappearance of littoral macrophyte, bank erosion and reduction of economic fishery prod... Yuxi River-Chaohu Lake water suffers greatly from the ecological problems of eutrophication, high turbidity, organic pollution, disappearance of littoral macrophyte, bank erosion and reduction of economic fishery products. With Micro-cystis dominant, it is a degenerated and weak ecosystem. Its vicious cycling is caused by too much nutrient load, high spring water level and improper management of the water. The point sources of pollution from cities and industries contribute more than 50% of nutrient load. Soil erosion and fertilizer loss from late rice fields are important factors in non-point nutrient load. The disappearing littoral zone can neither give enough protection for the bank nor provide proper habitats for the biota. The feasibility of ' ecological water level proposal' and means to reduce nutrient load are discussed to improve the habitat environment for both the nature and human being. 展开更多
关键词 yuxi River Chaohu Lake eutrophication.
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Land Use Change in Hongta District in Yuxi City, China Based on Archived Landsat Data of the Past 30 Years
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作者 Shanyu Zhou Chaonan Ji +1 位作者 Ran Kang Hermann Kaufmann 《Journal of Computer and Communications》 2018年第11期138-145,共8页
Urban expansion, which has affected ecosystem functioning and services at local to global scale, is projected to have aggravating impacts on landscape in the future. A detailed study on spatiotemporal patterns of Hong... Urban expansion, which has affected ecosystem functioning and services at local to global scale, is projected to have aggravating impacts on landscape in the future. A detailed study on spatiotemporal patterns of Hongta District in Yuxi City over a relatively long timeframe was conducted using multi-temporal Landsat TM, ETM+ and OLI data of 1987-2017 associated with Geographic Information System techniques and landscape analysis approaches. Results showed that sealed surfaces (urban area) have expanded from 1.4% to 11.8%, with an annually increasing rate of 7.63%. Trees, farm areas and barren lands all underwent a slight reduction during this time period, whereby 23.8% of farms and 9.8% of bare lands transferred into sealed surfaces. Focusing on the urban expansion pattern, it presents a uninuclear polarizing polygon mode illustrating the urbanization sprawl over time to all directions. The greatest expansions are seen in NNE and SSE direction, mainly because of the topographic constraints. A trade-off between urbanization and sustainable development is under investigation by reclaiming barren soil at the mountain range to transfer farming areas from low altitude plains to make way for urban growth. 展开更多
关键词 URBANIZATION Land Use Change LANDSAT Archived DATA yuxi Hongta DISTRICT China
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Yuxi Cigarets Factory Strives to Be A World-Class Enterprise
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作者 Xin Wen 《China's Foreign Trade》 1994年第6期41-41,共1页
The Yuxi Cigarets Factory is located in Hongtashan in Yuxi, Yun’nan Province. Established in 1956, the factory is now the country’s biggest modern cigaret enterprise with more than 4,000 employees and fixed assets w... The Yuxi Cigarets Factory is located in Hongtashan in Yuxi, Yun’nan Province. Established in 1956, the factory is now the country’s biggest modern cigaret enterprise with more than 4,000 employees and fixed assets worth RMB600. With more than 100 pieces of world advanced production equipment and high-quality tobacco production bases, the factory produces eight brands including Yuxi, Hongtashan, 展开更多
关键词 World BE yuxi Cigarets Factory Strives to Be A World-Class Enterprise
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Characteristics of paleoflood deposits archived in unit T0403 of Yuxi Site in the Three Gorges reservoir areas,China 被引量:18
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作者 ZHU Cheng MA ChunMei +6 位作者 XU WeiFeng BAI JiuJiang ZHENG ChaoGui ZHU GuangYao WANG HuiLin CHEN Ye LU XueFeng 《Chinese Science Bulletin》 SCIE EI CAS 2008年第S1期1-17,共17页
Based on the detailed analyses,multi-proxies such as AMS 14 C dating,grain size,component and morphology of heavy minerals,micromorphology of zircon,magnetic susceptibility,Rb/Sr and Hg content are used to research th... Based on the detailed analyses,multi-proxies such as AMS 14 C dating,grain size,component and morphology of heavy minerals,micromorphology of zircon,magnetic susceptibility,Rb/Sr and Hg content are used to research the paleoflood sediments archived in the Yuxi Site.The research indicates that, since 7.6 kaBP,at least 16 times of paleoflood with water level above Wusong Elevation 147.024 m(a.s.l.) left deposits in the Neolithic layers of unit T0403 from the Yuxi Site.The results are induced from the following aspects:(1)The plaeoflood sediments take on great similarities with modern flood sediments in the Yuxi Site and Zhongba Site in probability cumulative curves which mainly show a pattern of 3 segments in fluvial pattern.(2)There is some resemblance between the heavy mineral components and the zircon shape characteristics of paleoflood deposits and those of modern flood deposits.(3) Magnetic susceptibility values(40.44―70.10SI)are lower than those of sediments from cultural layers (59.59―188.68SI).(4)Hg values(290.71―742.51 ng/g)are lower than those of sediments from cultural layers(344.16―10518.17 ng/g).(5)Rb/Sr values are higher than those of sediments from cultural layers, while those of the 4th,5th,6th,7th,8th cultural layers are high,which shows that they are inundated by paleoflood.The reason for many flood deposits existing is related to the site situated on the first terrace where the Yuxi River joins with the Yangtze River.As there are some similarities between the plaeoflood sediments and those of the Zhongba Site,it is feasible to confirm the existence of paleoflood sediments based on the above points. 展开更多
关键词 Three Gorges reservoir areas UNIT T0403 of yuxi SITE CHARACTERISTICS of paleoflood deposits probability CUMULATIVE curve of grain size shape of ZIRCON geochemistry indexes
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Molecular epidemic survey on co-prevalence of scrub typhus and marine typhus in Yuxi city,Yunnan province of China 被引量:19
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作者 ZHANG Li-juan LI Xue-mei +4 位作者 ZHANG De-rong ZHANG Jing-shan DI Ying LUAN Ming-chun FU Xiu-ping 《Chinese Medical Journal》 SCIE CAS CSCD 2007年第15期1314-1318,共5页
Background Human rickettsioses are worldwide zoonoses and it is not easy to differentiate them from other infectious diseases because of their atypical manifestation. In recent years the number of patients with fever ... Background Human rickettsioses are worldwide zoonoses and it is not easy to differentiate them from other infectious diseases because of their atypical manifestation. In recent years the number of patients with fever of unknown causes from Hongta District CDC, Yuxi city of Yunnan Province has been increasing significantly in the summer. Diagnosis of scrub typhus was made by local clinicians. In order to ascertain the disease, we undertook a laboratory investigation for such patients from August 18 to 26, 2005. Methods Active surveillance was conducted by Hongta District CDC Yuxi city of Yunnan Province from 2002 to 2004 and basic data were obtained from cases confirmed according to clinical definitions. Average incidences and town-level incidences were calculated during the study periods. Blood samples were analyzed by PCR and serological test. Based on the groEL gene sequences a paired general outer primers (Gro-1 and Gro-2) targeting typhus, spotted fever as well as scrub typhus and two paired inner primers (SF1, SR2 and TF1, TR2) for typhus together with spotted fever and scrub typhus, respectively, were designed to perform a multiplex-nested PCR. Serological assay was carried out by indirect immunofluorescence assay with 7 different rickettsial antigens, i.e., R.mossori, R.sibirica, R.conorii, O.tsutsugamushi, B.quintana, B.henselae and Coxilella burnetii phase Ⅱ Ag. Results Epidemiological surveillance showed that from 2002 to 2004, the average incidences of the scrub typhus or scrub typhus with murine typhus were 222.1/10^5, 204.3/10^5 and 109.6/10^5, respectively. Of 13 blood samples taken during acute stage of illness, 6 showed the amplified products for scrub typhus and the sequenced products showed 100%, 99%, 99%, 99%, 99%, 99% similarity to O.tsutsugamushi Karp but they shared the same deduced amino acid sequences, which indicated 100% identity with the heat shock protein of the O.tsutsugamushi Karp strain. Five yielded PCR products for murine typhus and their corresponding nucleotide sequences exhibited 100%, 100%, 99%, 99% and 99% similarity to R. mossori Wilmington and the analyses of predicted amino acid sequences indicated 100%, 100%, 98%, 98% and 98% identity with the heat shock protein of R. mossoriWilmington strain. Of the 8 PCR positive patients, 3 showed a co-infection of scrub typhus with murine typhus. All the 13 serum samples from febrile patients were positive against O. tsutsugamushi and 8 of them were positive against R. mossori. All of the 8 paired specimens had four-fold elevation of antibody against O. tsutsugamushi, and seroconversion for typhus was demonstrated in 3 paired serum samples. Another finding in the study was that a high seropositive prevalence (76.9%) of Q fever was detected. Concluaion It's confirmed that co-prevalence of scrub typhus with murine typhus are occurring in Yuxi city of Yunnan province, China. Other rickettsial diseases also need to be investigated in these areas. 展开更多
关键词 scrub typhus murine typhus Q fever PREVALENCE yuxi
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Archaeological discovery and research on the remains of the paleoflood of the Yuxi site 被引量:5
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作者 BAI JiuJiang ZOU HouXi ZHU Cheng 《Chinese Science Bulletin》 SCIE EI CAS 2008年第S1期18-27,共10页
The research of the paleoflood remains from archaeological sites is one of the most important jobs in the environmental archaeology.Based on the traditional archaeological methods and the archaeological finds from the... The research of the paleoflood remains from archaeological sites is one of the most important jobs in the environmental archaeology.Based on the traditional archaeological methods and the archaeological finds from the Yuxi site,Fengdu County of Chongqing,the paper analyzes the difference between the cultural layers and the possible paleoflood layers from various angles,such as contents,shapes of gravels,pottery,etc.,identifies the possible paleoflood deposit layers,i.e.the paleoflood remains of the Yangtze River,and discusses the periodicity of the floods. 展开更多
关键词 paleoflood ENVIRONMENTAL ARCHAEOLOGY CULTURE LAYER POSSIBLE palieoflood LAYER yuxi SITE
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我言秋日胜春朝——刘禹锡对沧浪思想的生发
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作者 李垣璋 田运科 《湖北工业职业技术学院学报》 2026年第1期30-34,共5页
中唐以后,隐逸思想兴盛,沧浪思想在其中发挥了一定的作用。白居易和他的好友刘禹锡都写了不少沧浪诗作。并且白居易在沧浪思想原本的“遇治则仕,遇乱则隐”基础上生发出了中隐思想,刘禹锡则不同于白居易的消极、逃避,他以自身的人生经... 中唐以后,隐逸思想兴盛,沧浪思想在其中发挥了一定的作用。白居易和他的好友刘禹锡都写了不少沧浪诗作。并且白居易在沧浪思想原本的“遇治则仕,遇乱则隐”基础上生发出了中隐思想,刘禹锡则不同于白居易的消极、逃避,他以自身的人生经历和沧浪诗作,对沧浪思想作出了积极意义上的生发。 展开更多
关键词 沧浪 刘禹锡 白居易
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从“风寒束表”论王玉玺教授治疗银屑病的特色用药规律
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作者 温程越 刘畅 《亚太传统医药》 2026年第3期86-90,共5页
基于《伤寒论》六经辨证体系,系统探讨王玉玺教授从“风寒束表”理论辨治银屑病的特色用药规律,旨在完善中医皮肤病辨治思路。提出银屑病初起以风寒外袭太阳经表为发病之始,营卫失和为核心病机,内外合邪(外感风寒与内蕴湿浊痰瘀)是病情... 基于《伤寒论》六经辨证体系,系统探讨王玉玺教授从“风寒束表”理论辨治银屑病的特色用药规律,旨在完善中医皮肤病辨治思路。提出银屑病初起以风寒外袭太阳经表为发病之始,营卫失和为核心病机,内外合邪(外感风寒与内蕴湿浊痰瘀)是病情迁延难愈的关键;通过梳理典型医案,总结其“辛温透达以散表寒,固表通阳以和营卫”的核心治则,阐释荆芥、麻黄等辛温解表药与桂枝、白芍等调和营卫药的协同增效机制,揭示蜈蚣、全蝎等虫类药破瘀通络以改善顽固性皮损中的独特价值。王教授以“开玄府、调气血”为诊疗枢机,将“调和阴阳”理论融入临床,形成“祛邪扶正并重,气血同治兼顾”的创新思路,为银屑病中医治疗提供新路径,对丰富中医皮肤病“因地、因人辨证”体系具有重要学术价值。 展开更多
关键词 银屑病 风寒束表 营卫失和 辛温透达 王玉玺
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Geological and geochemical and genetic studies of Yuxi silver deposit in east Tianshan, Xinjiang
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作者 CHEN Shizhong~(1,2), ZHOU Jiyuan~2, CUI Binfang~2, XIAO Huiliang~2 and GU Lianxing~1 1. Nanjing University, Nanjing 210008, China 2. NIGMR, Nanjing 210016, China 《Chinese Science Bulletin》 SCIE EI CAS 1999年第S2期10-11,共2页
1 Geology Yuxi silver Deposit is located at mountain area of Tuzileike Salt 152 Km south to the Hami in XinjiangAutonomous Region. The ore is of the medium size and may be expected to be larger. Its geotectonicbackgro... 1 Geology Yuxi silver Deposit is located at mountain area of Tuzileike Salt 152 Km south to the Hami in XinjiangAutonomous Region. The ore is of the medium size and may be expected to be larger. Its geotectonicbackground belongs to Middle Tianshan crystalline block. The southeast part of regional Yuxi fracturezone, which is made up of a series of secondary faults and slivers-containing fragment tiering, ductileshear zones, and fracture zones, crosses the orefield. The exposed rocks in the orefield are mainly MiddleProterozoic Xingxingxia Group (Chxn), Kawabulak Group (Jxkw) and Upper Permian Darequanzi Formation. Kawabulak Group is a mineralizing wall rock, which is composed of magnesium-rich carbonate andunderwent high greenschist facies metamorphism. It is divided into five laryers by rock. Silver mineraliza- 展开更多
关键词 GENESIS yuxi silver deposit EAST Tianshan.
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唐代新乐府的入乐篇目及其辞乐关系
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作者 张哲俊 《齐鲁学刊》 北大核心 2026年第1期142-151,共10页
唐代新乐府不入乐是常见看法,近来有学者认为新乐府亦曾入乐,但没有提供曾经入乐的新乐府篇目。如果不能确定新乐府的入乐篇目,那么新乐府曾经入乐的说法无法确证,也就难以摆脱假说的色彩。新乐府确有入乐篇目,《刘宾客文集》卷二十七... 唐代新乐府不入乐是常见看法,近来有学者认为新乐府亦曾入乐,但没有提供曾经入乐的新乐府篇目。如果不能确定新乐府的入乐篇目,那么新乐府曾经入乐的说法无法确证,也就难以摆脱假说的色彩。新乐府确有入乐篇目,《刘宾客文集》卷二十七的乐府是根据播于乐章的歌辞编辑的,因而可以确定是入乐篇目。这些入乐篇目还能提供关于新乐府的入乐方式的重要信息。新乐府采用了新曲新辞的入乐方式,也采用了文学名称与音乐名称之双名体制。发现新的文献固然能够推动新乐府的研究,但在寻常文献中仍然能够发现前人没有注意的信息,这也是重要的研究方法。 展开更多
关键词 新乐府 刘禹锡 白居易 元稹 入乐篇目 辞乐关系
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玉溪市古树名木保护现状及发展对策
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作者 王兴 《林业勘查设计》 2026年第1期67-71,共5页
以玉溪市古树名木为研究对象,分析其保护现状及面临的问题与挑战,并提出针对性策略以优化保护工作,推进古树名木持续保护和发展利用。探索保护性移植,推进有害生物防控、复壮养护技术标准化及普及“树木致害过错推定责任”,同时从立法... 以玉溪市古树名木为研究对象,分析其保护现状及面临的问题与挑战,并提出针对性策略以优化保护工作,推进古树名木持续保护和发展利用。探索保护性移植,推进有害生物防控、复壮养护技术标准化及普及“树木致害过错推定责任”,同时从立法、人才和资金方面给予保障,为玉溪市乃至更广泛地区的古树名木保护与开发提供可行路径。在此框架下,通过提升管理效率和促进跨部门协作,有望推动古树名木的保护与利用达到新的高度,实现可持续发展。 展开更多
关键词 古树名木 保护现状 发展对策 玉溪市
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玉溪市红塔区地表水环境监测存在的问题及解决措施
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作者 刘涛 《中国资源综合利用》 2026年第2期222-224,共3页
玉溪市红塔区地表水资源总量有限,水环境风险较高。为提升地表水环境监测的精准性与实效性,助力区域水资源保护与可持续利用,分析红塔区地表水环境监测在覆盖范围、指标设置及运维保障方面的实际情况。分析认为,当前,红塔区地表水环境... 玉溪市红塔区地表水资源总量有限,水环境风险较高。为提升地表水环境监测的精准性与实效性,助力区域水资源保护与可持续利用,分析红塔区地表水环境监测在覆盖范围、指标设置及运维保障方面的实际情况。分析认为,当前,红塔区地表水环境监测存在覆盖不均衡、指标针对性不足、运维支撑乏力等突出问题,应该从优化站点布局、细化监测指标、完善运维机制等方面入手,系统地改善地表水环境监测质量。 展开更多
关键词 地表水 环境监测 玉溪市红塔区
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玉溪市草原毒害草发生趋势及风险评估
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作者 高景芳 《林业调查规划》 2026年第1期160-169,共10页
为摸清玉溪市草原毒害草种类及分布情况,评估毒害草发生现状及趋势,科学指导灾害防治工作,通过踏查结合标准地调查,调查到毒害草103种;危害的主要方式为侵占、有毒。采用物种重要值评估物种发生程度,紫茎泽兰是种群的绝对优势种,白花鬼... 为摸清玉溪市草原毒害草种类及分布情况,评估毒害草发生现状及趋势,科学指导灾害防治工作,通过踏查结合标准地调查,调查到毒害草103种;危害的主要方式为侵占、有毒。采用物种重要值评估物种发生程度,紫茎泽兰是种群的绝对优势种,白花鬼针草、蕨为种群优势种,其余物种为一般常见物种。采用ArcGIS软件核密度分析工具对“密度”进行分析,将分析结果可视化,重点毒害草不同程度分布在玉溪市,其中澄江市、易门县毒害草密度高,整体有由高密度区向低密度区扩散趋势。运用最大熵(MaxEnt)模型结合ArcGIS软件空间分析,对重点毒害草适生区开展风险评估,紫茎泽兰高风险区集中在易门县,白花鬼针草高风险区集中在红塔区,飞机草高风险区集中在新平县和元江县境内红河两岸,蕨高风险区集中在澄江、华宁、通海等县(市)和江川区南部交界区域。运用刀切法测定环境变量对重点毒害草在玉溪市生存的重要性,根据环境变量对其分布重要性的结果图分析,影响紫茎泽兰、白花鬼针草、飞机草、蕨生存的主要环境因子中的主导因子分别是最冷月最低温度、温度季节性、最热月最高温度、年均温。 展开更多
关键词 毒害草 危害方式 发生程度 发生趋势 风险评估 ARCGIS MaxEnt模型 玉溪市
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裕溪河汇入长江河口段航道通航水流条件研究
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作者 孙腾飞 王玉生 李媛媛 《水运工程》 2026年第1期128-137,共10页
裕溪河汇入长江河口段的通航水流条件受上游船闸枢纽调度与长江干流水沙条件的双重作用影响,表现出复杂的特性。研究通过构建深度平均的平面二维水动力模型,对航道整治后裕溪河口的水深、流速、流向等通航水流条件进行了系统分析;基于Pe... 裕溪河汇入长江河口段的通航水流条件受上游船闸枢纽调度与长江干流水沙条件的双重作用影响,表现出复杂的特性。研究通过构建深度平均的平面二维水动力模型,对航道整治后裕溪河口的水深、流速、流向等通航水流条件进行了系统分析;基于Perrson相关性系数分析方法,研究枢纽运行方式对河段原弯道分流比的影响。结果表明:基于现状航道尺度要求,设计航槽内基本能满足4.0 m的维护水深要求,但存在局部区域航道水深不足的问题;工程河段的流态整体上直接受长江干流水位及裕溪闸运行泄流状态的控制。当长江干流的顶托作用较弱且裕溪闸泄流流量较小,河段整体的水动力条件相对较弱;原弯段与枢纽下泄总量、节制闸流量存在较强正相关关系,而与船闸冲灌水量呈负相关。研究成果可为裕溪河口段船舶安全提供参考,并为后续航道维护提供理论支持。 展开更多
关键词 裕溪河口 通航水流条件 流速流向 水深变化 数值模拟
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玉溪市水稻机插秧技术规模化推广优化路径研究
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作者 洪春海 李海翔 李存寿 《中国农机装备》 2026年第1期128-130,共3页
基于玉溪市农业机械推广站2024年实地调研数据,聚焦丘陵山区农业生产特性,系统探究水稻机插秧规模化推广的成本构成、效益机制、实践成效及现实瓶颈。分析数据表明,机插秧较传统人工插秧每亩节本185—230元、增产率6.2%—8.5%,效益优势... 基于玉溪市农业机械推广站2024年实地调研数据,聚焦丘陵山区农业生产特性,系统探究水稻机插秧规模化推广的成本构成、效益机制、实践成效及现实瓶颈。分析数据表明,机插秧较传统人工插秧每亩节本185—230元、增产率6.2%—8.5%,效益优势源于“机械替代人工”要素重构与北斗导航机具的精准技术赋能。但是机插秧技术推广受田块碎片化、机具成本高、服务不均等问题制约。结合当地地形与生产实际,提出了土地优化、差异化补贴、网格化服务等对策,为西南丘陵山区水稻机械化生产提供实证参考。 展开更多
关键词 玉溪市 水稻机插秧 规模化推广 成本效益机制 优化路径
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