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Landscape structure and land uese on county level in northeastern Yunnan Province of China——a case study of Huize County 被引量:5
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作者 WANG Jin\|liang, NI Shao\|xiang (College of Geographical Science, Nanjing Normal University, Nanjing 210097, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第3期355-360,共6页
Taking Huize County as an example, the paper analyzed the landscape structure(landscape element structure, landscape type structure, landscape spatial structure, landscape succession structure) and the relations betwe... Taking Huize County as an example, the paper analyzed the landscape structure(landscape element structure, landscape type structure, landscape spatial structure, landscape succession structure) and the relations between landscape structure and land use. It was pointed out that the agriculture should be developed in harmony with the landscape structure in the study area. 展开更多
关键词 landscape structure land use AGRICULTURE yunnan province China
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Effect of ground cover changes on solar radiation absorption in Three Northeastern Provinces of China
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作者 SHUAI Yanmin CHEN Yangyang +3 位作者 SHAO Congying TIAN Yanjun QU Ge HUANG Jiapeng 《地球环境学报》 CSCD 2024年第4期675-690,共16页
Background,aim,and scope Solar radiation is the main source of energy for terrestrial ecosystems.Small changes in the absorption of solar radiation at the ground surface can have a significant impact on the climatic e... Background,aim,and scope Solar radiation is the main source of energy for terrestrial ecosystems.Small changes in the absorption of solar radiation at the ground surface can have a significant impact on the climatic environment.Natural and anthropogenic changes in ground cover are important factors affecting the absorption of solar radiation at the ground surface.This phenomenon is particularly pronounced in the mid and high latitudes.In order to quantify the inf luence of surface cover change on the absorption of solar radiation at the surface and to provide a scientific basis for changes in the climatic environment,this paper analyzed ground cover change,ground absorbed solar radiation change and the effect of ground cover change on ground absorbed solar radiation in the Three Northeastern Provinces of China from 2001 to 2018.Materials and methods In this study,the Three Northeastern Provinces of China were used as the study area.Firstly,satellite remote sensing data were used to obtain land cover data and albedo data for Aug.1st of each year in 2001,2005,2010,2015 and 2018.The albedo data were further used to calculate the absorbed solar radiation data at the ground surface.Next,the land cover data were used to count the area changes and shifts of different land classes over the five-year period.The land cover data were overlaid with the surface absorbed solar radiation data to obtain the mean and standard deviation of radiation absorption for different ground classes.The surface absorbed solar radiation data were subtracted to obtain the changes in surface absorbed solar radiation for 2001-2005,2005-2010,2010-2015 and 2015-2018.Ultimately,we used a combination of shifted changes in ground classes and changes in surface absorbed solar radiation data,with unchanged ground classes as a baseline and data such as slope orientation as an aid.We analyzed the effect of ground cover change on surface absorbed solar radiation at regional and pixel point scales.Results(1)The area of woodland and waters in the Three Northeastern Provinces of China increased and then decreased from 2001 to 2018,with an overall increase of 3.96%and 10.51%respectively.Cropland decreased and then increased,with a total decrease of 1.22%.Grassland continued to decrease,with an overall decrease of 19.36%.Building sites increased all the time,with a total increase of 11.08%.The main types of ground cover shifted were woodland,cropland and grassland.The main factors for the change in ground cover were China’s woodland protection policy and the saturation of the total woodland stock.(2)The five ground types absorb solar radiation in the order of waters>building sites>woodland>grassland>cropland.The surface absorption of solar radiation in the Songnen Plain,the Sanjiang Plain and the Songhua River Basin flowing through the Songnen Plain and the Sanjiang Plain varies significantly,by more than 25 W·m^(-2).(3)Changes in the ground cover type affected the absorption of solar radiation energy by the ground surface.There was a clear trend of interconversion between waters and cropland/grassland,cropland and woodland/grassland.In particular,the conversion of waters to both cropland and grassland radiation absorption values decreased significantly,while the opposite increased.The absolute difference between waters and cropland was a maximum of -156.66 W·m^(-2)in 2010-2015,and between waters and grassland was a maximum of 102.36 W·m^(-2) in 2005-2010.The radiative absorption values of woodland and grassland reclamation declined and conversely increased.The absolute difference between woodland and cropland was a maximum of-13.94 W·m^(-2) in 2010-2015 when woodland converted to cropland,and between grassland and cropland was a maximum of 22.36 W·m^(-2) in 2001-2005 when cropland converted to grassland,respectively.Discussion Ground cover changes in the Three Northeastern Provinces of China from 2001-2018 were inextricably linked to natural factors and the inf luence of Chinese national policies.The main inf luencing factors were China’s woodland protection policy,restoration of woodland fire sites,saturation of total woodland,optimization of cropland patterns,sanding of grassland,expansion of water conservancy projects,and urbanization expansion.There were differences in the radiation absorption characteristics of different ground cover types.This was due to the nature of the ground type itself and the regional environment.When ground cover types changed,their ability to absorb solar radiation also changed.The degree of change could be inf luenced by different ground types and different environmental factors.Different spatial scales can also produce variability.We need to consider the effects of ground cover change on the absorption of solar radiation at the surface in an integrated and comprehensive way.Conclusions The Three Northeastern Provinces of China had frequent changes in ground cover from 2001-2018,with the area of grassland decreased by almost 20%.These changes were due to natural environmental change and policies issued by China since the 21st century.The extent to which solar radiation was absorbed by different ground cover types was different,with grassland being the strongest and cropland the least.In the past few years,the Songnen Plain and Sanjiang Plain regions were the most significant changes in the absorption of solar radiation by the ground cover.The change in ground cover type led to a change in solar radiation absorption at the ground surface,with the conversion of waters to cropland or grassland and the conversion of cropland to woodland or grassland showing the greatest change in radiation absorption values,and vice versa.Of these,the absolute difference in the conversion of waters to cropland amounts to-156.66 W·m^(-2) in 2010-2015.The variation in the absorption of solar radiation at the ground surface was related to the characteristics of the ground class itself,but was also limited by the regional environment.Recommendations and perspectives This study showed that surface cover change can affect the absorption of solar radiation at the surface to varying degrees.The unchanged land classes were used as a comparative analysis in this paper,and it was clear from the paper that some of the unchanged land classes showed significant changes in radiation absorption that should be of interest in future studies. 展开更多
关键词 land surface cover changes surface absorption of solar radiation the Three northeastern provinces ALBEDO
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Integrated Prevention and Control Technology for Coffee Leaf Rust in Yunnan Province
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作者 Xingfei FU Guiping LI Faguang HU 《Asian Agricultural Research》 2024年第11期25-28,共4页
This paper investigates the damage symptoms and occurrence regularity related to coffee leaf rust,and proposes a comprehensive prevention and control strategy grounded in the principle of prioritizing prevention and i... This paper investigates the damage symptoms and occurrence regularity related to coffee leaf rust,and proposes a comprehensive prevention and control strategy grounded in the principle of prioritizing prevention and implementing integrated prevention and control.This strategy encompasses the cultivation of rust-resistant varieties,the implementation of agricultural practices,the application of chemical interventions,the utilization of hyperparasitic fungi,and the protection and utilization of natural enemies.The paper further outlines the necessary requirements for effective prevention and control,emphasizing the importance of enhancing responsibility implementation,fostering systematic prevention and control measures,enhancing guidance services,and increasing publicity and guidance.The aim is to offer technical guidance for the integrated prevention and control of coffee leaf rust in Yunnan Province. 展开更多
关键词 Coffee leaf rust disease Damage symptoms Occurrence regularity Integrated prevention and control yunnan province
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Difference Analysis on Contents of Gallic Acid and Catechins of Tea Resources from Yunnan Province 被引量:3
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作者 罗向前 王家金 +6 位作者 孙雪梅 李友勇 刘本英 汪云刚 宋维希 马玲 周玉忠 《Agricultural Science & Technology》 CAS 2012年第12期2502-2506,2614,共6页
[Objective] This study aimed to analyze the difference in the contents of gallic acid and catechins of tea resources from Yunnan Province. [Method] By using high performance liquid chromatography (HPLC), the content... [Objective] This study aimed to analyze the difference in the contents of gallic acid and catechins of tea resources from Yunnan Province. [Method] By using high performance liquid chromatography (HPLC), the contents of gallic acid (GA), catechins (C), epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG) and epigallocatechin gallate (EGCG) of 121 tea germplasms from the China National Germplasm Tea Repositories (CNGTR) at the Tea Research Institute of Yunnan Academy of Agricultural Sciences (TRIYAAS) were measured. [Result] The content of GA ranged from 0.210% to 1.902%, with an average of 0.834%, explaining rela- tively low GA content among tea germplasms. The content of C ranged from 0.069% to 8.865%, with an average of 1.916%. The content of EC ranged from 0.126% to 2.865%, with an average of 1.112%. The content of EGC ranged from 0.00% to 3.709%, with an average of 0.954%. The content of ECG ranged from 0.739% to 8.957%, with an average of 4.063%. The content of EGCG ranged from 0.819% to 11.77%, with an average of 5.939%. The content of total C ranged from 6.354% to 22.654%, with an average of 14.042%. [Conclusion] There was relatively big difference of catechin contents among different tea resources, indicating that there was plentiful biodiversity of Yunnan tea germplasms. At the same time, three tea germplasms with high epigallocatechin gallate content (≥10%) was selected preliminarily, which would provide important materials for breeding tea cultivars with high EGCG content in the future. 展开更多
关键词 yunnan province Tea germplasm Gallic acid CATECHINS DIFFERENCE
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Analysis on the Necessity and Feasibility of Implementing the Strategy of "Protecting Farmland in Flatland Areas and Constructing Mountainous Cities" in Yunnan Province 被引量:3
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作者 贺一梅 杨子生 邹金浪 《Agricultural Science & Technology》 CAS 2015年第4期769-773,共5页
Yunnan is one of the most typical mountalnous provinces in western Chi-na. For the geographical features of mountalnous areas accounting for most parts and fIatIand areas accounting for smal parts, the contradiction b... Yunnan is one of the most typical mountalnous provinces in western Chi-na. For the geographical features of mountalnous areas accounting for most parts and fIatIand areas accounting for smal parts, the contradiction between farmIand protection and construction guarantee is very prominent. In the first half of 2011, Yunnan Province estabIished creativeIy the strategy of &quot;protecting farmIand in fIat-Iand areas and constructing mountalnous cities&quot; (hereinafter referred to as the strat-egy of &quot;constructing mountalnous cities&quot;), which was almed at protecting effectiveIy the Iimited and high quality arabIe Iand resources in fIatIand area and providing new construction area for new type of urbanization and industrialization, so as to achieve win-win situation between arabIe Iand protection and urbanization deveIopment. Im-pIementing this strategy in Yunnan Province is feasibIe, malnIy in the Iarge deveIop-ment potentials in the gentIe gradient between 8° to 25°. The gentIe sIope area be-tween 8° to 25° occupies 51% of the total Iand area in Yunnan Province, which is almost 140 times of the area of urban construction Iand in Yunnan in 2009. The surrounding areas of fIatIand or maln town in most counties (cities, regions) dis-tribute with different sizes of Iow hiI s and gentIe sIopes, thus mountalnous construc-tion Iand reserves are abundant, which benefits for impeI ing the strategy of &quot;con-structing mountalnous cities&quot; in the Iight of Iocal conditions. 展开更多
关键词 Constructing mountalnous citles STRATEGY NECESSITY Feasibliity yunnan province
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Study on Urban Construction Land Suitability Evaluation in Southwestern Mountainous Areas of Yunnan Province Based on the Strategy of "Protecting Farmland in Flatland Areas and Constructing Mountainous Cities" : A Case in Lianghe County 被引量:4
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作者 贺一梅 杨子生 +2 位作者 张博胜 邓有旺 张德省 《Agricultural Science & Technology》 CAS 2014年第10期1774-1777,1780,共5页
According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat ... According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat area. Then this study deter- mined single evaluation factors index and comprehensive suitability index using "ex- treme conditions method" and "suitability index method", and analyzed and assessed the constructive land suitability on each evaluation unit polygons and its suitability level by using GIS software. Taking Lianghe County of Dehong Dai-Jingpo Au- tonomous Prefecture as an example to evaluate land suitability in Lianghe County's main towns around the gentle slope, the results show, in the evaluation area, the area of land suitable for construction and unsuitable for construction respectively ac- count 73.58% and 26.42%. And first-class, second and third-class of land suitable for construction should be composited at the ratio of about 11:49:40. The suitability evaluation index system and method developed in this paper is applicable for evalu- ating the construction land suitability in mountainous areas of southwest Yunnan Province, and will provide theoretical and technical support for land policy measures which strengthen the protection of farmland and promote the scientific development of urbanization in Yunnan Province and even similar mountainous areas of the whole China. 展开更多
关键词 Mountainous area Constructive land Suitability evaluation Comprehensive suitability index Southwestern yunnan province
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Relation between Economic Development Level and Resource and Environment Carrying Capacity of Central Area of Yunnan Province Based on Decoupling Analysis 被引量:4
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作者 程超 童绍玉 +2 位作者 彭海英 闫少凯 刘玲 《Agricultural Science & Technology》 CAS 2015年第12期2829-2832,共4页
Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling ... Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling degree and temporal changes of economic development level and resource and environment carrying ca- pacity in the central area of Yunnan Province. Results indicated that (i) the economic development level and resource and environment carrying capacity in the central area of Yunnan Province mainly experienced strong decoupling, weak decoupling, and ex- pansive negative coupling, and in general it was strong decoupling, and it took on re- verse "N" in temporal changes. (ii) Change rate of economic development level in the central area of Yunnan Province was greater than zero, but the amplitude of change was not large, while the change rate of resource and environment carrying capacity was negative in 2007-2008, and it was positive in the rest years; from 2007, it took on gradual expansion trend, and scissors difference gradually increased after experi- encing reverse "V" change. (iii) The strong decoupling was the main situation and it reached the peak value in T5 period and T6 pedod. 展开更多
关键词 The central area of yunnan province Economic development level Re- source and environment carrying capacity Decoupling analysis Scissors difference
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A Preliminary Survey on Pest of Bamboo in Yunnan Province 被引量:2
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作者 和秋菊 易传辉 +2 位作者 杨宇明 孙茂盛 王飞 《Agricultural Science & Technology》 CAS 2009年第1期153-156,共4页
In order to improve the development step of bamboo industry, the pest investigation was done in Yunnan Province from 2000, and 1 500 specimens were collected. Basing on the investigation and the date of recordation, t... In order to improve the development step of bamboo industry, the pest investigation was done in Yunnan Province from 2000, and 1 500 specimens were collected. Basing on the investigation and the date of recordation, there had 224 species pests, belonging to 7 orders and 49 families. Among the pest, most done harm to the bamboo slightly, except Omphisa sp., Pantana phyllostachysae and Cyrtotrachelus buqueti. The disease and pest of bamboo should be investigated in whole province systematically. 展开更多
关键词 yunnan province BAMBOO PEST
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A Study on Vertical Spatial Transfer of Cultivated Land in Yunnan Province from 1986 to 2008 被引量:8
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作者 童绍玉 鲁永新 《Agricultural Science & Technology》 CAS 2011年第1期127-132,共6页
Based upon ArCGIS,the vertical spatial transfer law of cultivated land in Yunnan was studied through referring to three periods of remote sensing data of Land-Use and Land-Cover Change(LUCC) in Yunnan in 1986,1995 a... Based upon ArCGIS,the vertical spatial transfer law of cultivated land in Yunnan was studied through referring to three periods of remote sensing data of Land-Use and Land-Cover Change(LUCC) in Yunnan in 1986,1995 and 2000,Digital Elevation Model(DEM) of Yunnan Province and LUCC data in Yunnan from 2000 to 2008.The main factors that promote vertical spatial transfer law of cultivated land were analyzed by using SPSS,and the influence of policies and government acts upon the change of cultivated land was clarified.The findings indicated that for Yunnan cultivated land there is a trend that in the vertical direction steep slope areas and gentle slope areas divert into mid-slope areas.The primary factor influencing the vertical spatial transfer of cultivated land was policies and government acts.Also,the gradient of ground,total population and number of agriculture employed persons were also main factors in influencing the change of cultivated land,whose influence was obviously below policies and government acts. 展开更多
关键词 Cultivated land Vertical Spatial Transfer Driving factors Plicies yunnan province
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The Measurement and Grading of Pressure on Cultivated Land in City-level in Yunnan Province 被引量:3
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作者 杨青 杨子生 《Agricultural Science & Technology》 CAS 2015年第7期1562-1564,共3页
For a long time pressure on cultivated land receives much concern be- cause of close relationship with food security. In Yunnan provice,natural conditions of mountain area are poor and the overall quality of cultivate... For a long time pressure on cultivated land receives much concern be- cause of close relationship with food security. In Yunnan provice,natural conditions of mountain area are poor and the overall quality of cultivated land is :not high. This paper selected state (city) level as research scale,calculated the pressure index on cultivated land of 16 states (cities) in Yunnan provice,revealed the level of tension states (cities) of cultivated land,provided basic basis for determining amount of culti- vated land of provice and states and developing the policy about cultivated land protection.The study indicated that pressure on cultivated land in Dehong belongs to "no pressure" grade,in Qujing and Baoshan belong to "critical pressure "grade,in Yuxi and Zhaotong belong to "moderate-pressure"grade,in Kunming and Nujiang be- longs to "high-pressure" and in the rest 9 states belongs to "low-pressure"grade. 展开更多
关键词 Pressure on cultivated land GRADING yunnan province
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Analysis of Land Use Characteristics in Mountainous Areas in Yunnan Province Based on Second National Land Survey 被引量:2
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作者 芦艳艳 杨子生 《Agricultural Science & Technology》 CAS 2014年第9期1438-1440,共3页
Abstract Based on Second National Land Survey during 2007-2009 and land use type survey in ftatland areas, status quo of land use in mountainous areas in Yun- nan was measured, and analysis was made on land use in mou... Abstract Based on Second National Land Survey during 2007-2009 and land use type survey in ftatland areas, status quo of land use in mountainous areas in Yun- nan was measured, and analysis was made on land use in mountainous areas in terms of land use structure, degree and development potential, providing references for rational use of land in mountainous areas in Yunnan. 展开更多
关键词 Second national land survey Mountainous areas Land use Character- istics: yunnan province
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Land Use Situation and Strategies under the Background of New Urbanization in Yunnan Province 被引量:1
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作者 王保顺 廖顺宽 +2 位作者 王静 王箫睿 杨明龙 《Agricultural Science & Technology》 CAS 2015年第5期1053-1055,1059,共4页
Scientific analysis and determination of land use lays foundation for regional sustainable development under the background of new urbanization. The research made a comprehensive analysis on land uses in Yunnan under ... Scientific analysis and determination of land use lays foundation for regional sustainable development under the background of new urbanization. The research made a comprehensive analysis on land uses in Yunnan under the background of urbanization and proposed strategies for further development, providing references for land uses scientific decision making. 展开更多
关键词 New urbanization Land use Situation and strategy yunnan province
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Responses of the Anthocyanin and Osmolyte Contents of the Capsicum annuum Cultivars Planted in Wenshan Prefecture of Yunnan Province to the Drought Stress Simulated by PEG-6000 被引量:3
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作者 李云 孟凡来 +6 位作者 赵昶灵 屈用函 袁恩平 杨羚钰 张雪廷 王绍祥 赵水灵 《Agricultural Science & Technology》 CAS 2016年第6期1295-1300,1335,共7页
[Objective] The aim of this study was to compare the drought resistance difference of the main Capsicum annuum cultivars planted in Wenshan Prefecture of Yunnan Province. [Method] The total anthocyanin, soluble sugar,... [Objective] The aim of this study was to compare the drought resistance difference of the main Capsicum annuum cultivars planted in Wenshan Prefecture of Yunnan Province. [Method] The total anthocyanin, soluble sugar, soluble protein and free proline contents of the leaves of the five main C. annuum cultivars planted in Wenshan Prefecture, i.e., ZSZ75-1, ZSZ49-1-1, 12WS-18-1, 12ZH01 and ZS130, under the drought stress simulated by PEG-6000 were studied by using spectrophotometry, and the total osmoregulation abilities of the leaves were evaluated by using subordinate function. [Result] Under the drought stress simulated by PEG-6000, the total anthocyanin contents of the veins, mesophylls and whole leaves of the five cultivars were all as: ZSZ75-1〉ZSZ49-1-1〉12WS-18-1〉12ZH01〉ZS130, the soluble sugar contents as: 12ZH01 〉12WS-18-1 〉ZS130〉ZSZ49-1-1 〉ZSZ75-1, the soluble protein contents as: ZSZ75-1〉12ZH01〉ZSZ49-1-1〉12WS-18-1〉ZS130, and the free proline contents as: ZS130〉ZSZ75-1 〉12WS-18-1 〉ZSZ49-1-1 〉12ZH01. Furthermore, the differences among the total anthocyanin contents of the veins, mesophylls and whole leaves of the five cultivars all reached the extremely significant levels, whereas the differences among the contents of the soluble sugar, soluble protein and free proline did not reach the significant levels, the correlation degrees among the contents of the total anthocyanin, soluble sugar, soluble protein and free proline of different cultivars were also inconsistent, and the total osmoregulation abilities of the five cultivar leaves were as: ZSZ75-1 〉7SZ49-1-1 〉12WS-18-1 〉ZS130〉12ZH01. [Conclusion] The anthocyanin accumulation in the specific organs of the five C. annuum cultivars in Wenshan Prefecture is beneficial to the strengthening of the leaf osmoregulation abilities under drought stress, favoring the drought tolerance of the cultivars. 展开更多
关键词 Main Capsicum annuum cultivars planted in Wenshan Prefecture of yunnan province Anthocyanin content Osmolyte contents Drought stress simulated by PEG-6000 Response
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New Eusauropod Dinosaur from Yuanmou of Yunnan Province, China 被引量:6
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作者 LUE Junchang LI Shaoxue +3 位作者 JI Qiang WANG Guofu ZHANG Jiahua DONG Zhiming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期1-10,共10页
Yuanmousaurusjiangyiensis gen. et sp. nov. is erected based on an incomplete skeleton. It is characterized by more complex structures of the neural arches in the dorsal vertebrae than those in Omeisaurus, but less com... Yuanmousaurusjiangyiensis gen. et sp. nov. is erected based on an incomplete skeleton. It is characterized by more complex structures of the neural arches in the dorsal vertebrae than those in Omeisaurus, but less complex than those of Euhelopus; the dorsal vertebra bears 9 laminae, forming three cavities on the lateral surface of the neural arch; the dorsal vertebral neural spines with dorsoventrally-oriented cavities are similar to those of Omeisaurus and Patagosaurus. Yuanmousaurus is more primitive than Euhelopus, but more derived than Omeisaurus. The similar dorsal vertebral structure between Yuanmousaurus and Patagosaurus may indicate that they have a close relationship to each other. 展开更多
关键词 Yuanmou yunnan province Middle Jurassic Yuanmousaurus SAUROPODA
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Lead Isotopic Composition and Lead Source in the Bainiuchang Ag-polymetallic Deposit, Yunnan Province, China 被引量:8
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作者 ZHU Chaohui ZHANG Qian +2 位作者 SHAO Shuxun ZHU Xiaoqing WANG Dapeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第4期845-857,共13页
The Bainiuchang deposit in Yunnan Province, China, is located geographically between the Gejiu ore field and the Dulong ore field. In addition to the 〉7000 t Ag reserves, the deposit also boasts of large-scale Pb, Zn... The Bainiuchang deposit in Yunnan Province, China, is located geographically between the Gejiu ore field and the Dulong ore field. In addition to the 〉7000 t Ag reserves, the deposit also boasts of large-scale Pb, Zn and Sn reserves with a lot of dispersed elements (In, Cd, Ge, Ga, etc.). We have determined systematically the Pb isotope composition of the deposit. The Pb isotope ratios of the ores that are of sea-floor exhalative sedimentary origin in the northwest of the mining district, are 206pb/204pb = 17.758-18.537, 207pb/204pb = 15.175-15.862 and 206pb/204pb = 37.289-39.424, while those of ores that are of magmatic hydrothermal superimposition origin in the southeast of the mining district, are 206pb/204pb = 17.264-18.359, 207pb/204pb = 14.843-15.683 and 208pb/204pb = 36.481-38.838, respectively. In terms of the Pb isotope composition of feldspar in magmatic rocks or magmatic whole- rock samples from the mining district, we have determined the Pb isotope composition and acquired the Pb isotope ratios as: 206pb/204pb -- 18.224-18.700, 207pb/204pb -- 15.595-15.797 and 208pb/204pb -- 38.193-39.608. Then, in the light of the Pb isotope composition of metamorphic rock samples from the Proterozoic basement exposed in the Dulong ore field, we have determined the Pb isotope composition and obtained the isotope ratios as: 206pb/204pb -- 18.434-19.119, 207pb/204pb -- 15.644-15.693, and 208pb/204pb = 38.514-38.832. And the Pb isotope ratios of Cambrian sedimentary rocks, which are exposed in the Bainiuchang mining district, are 206pb/204pb = 18.307-19.206, 207pb/204pb = 15.622-15.809, and 208pb/204pb = 38.436-39.932. By comparing the two types of ores with respect to their Pb isotope compositions, it is indicated that lead in the Bainiuchang deposit was derived largely from the lower-crust granulite which is earlier than Neoproterozoic in age, but the Yanshanian magmatic hydrothermal fluids probably provided a part of ore-forming elements such as Sn for the ore blocks in the south of the mining district. 展开更多
关键词 Bainiuchang Ag-polymetallic deposit lead isotope lead source southeast yunnan province
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Distribution and development strategy for Jatropha curcas L. in Yunnan Province, Southwest China 被引量:9
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作者 Li Kun Yang Wen-yun +3 位作者 Li Li Zhang Chun-hua Cui Yong-zhong Sun Yong-yu 《Forestry Studies in China》 CAS 2007年第2期120-126,共7页
Yunnan Province is the main distributing area ofJatropha curcas L. This plant is abundant in several drainage areas of the dry-hot, dry-warm and sub-humid valleys in the south subtropical area of Yunnan Province. The ... Yunnan Province is the main distributing area ofJatropha curcas L. This plant is abundant in several drainage areas of the dry-hot, dry-warm and sub-humid valleys in the south subtropical area of Yunnan Province. The seeds that were picked from trees blossoming between April and May and fructifying between September and October will have large seed yield and fine quality. For developing bio-diesel stock forest ofJ. curcas in areas with adaptive climate, seeding measures for afforestation should be taken and techniques on breeding, fast-growing, and high-yielding plantation cultivation are very important. 展开更多
关键词 yunnan province Jatropha curcas L. geographical distribution resource status
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Geological Characteristics and Ore-controlling Factors of the Beiya Gold–Polymetallic Ore Deposit, Northwestern Yunnan Province 被引量:9
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作者 ZHOU Yunman ZHANG Changqing +4 位作者 HE Zhonghua LIU Huan ZHOU Guiwu SUN Jia LIU Bo 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期1841-1861,共21页
Based on comprehensive petrological, geochronological, and geochemical studies, this study analyzed the relationships between the Beiya gold-polymetallic skarn deposit and quartz syenite porphyries, and discussed the ... Based on comprehensive petrological, geochronological, and geochemical studies, this study analyzed the relationships between the Beiya gold-polymetallic skarn deposit and quartz syenite porphyries, and discussed the source(s) and evolution of magmas. Our results suggest that syenite porphyries(i.e. the Wandongshan, the Dashadi, and the Hongnitang porphyries), which formed between the Eocene and the early Oligocene epochs, are the sources for the gold-polymetallic ores at the Beiya deposit. Carbonate rocks(T2 b) of the Triassic Beiya Formation in the ore district provide favorable host space for deposit formation. Fold and fault structures collectively play an important role in ore formation. The contact zone between the porphyries and carbonates, the structurally fractured zone of carbonate and clastic rocks, and the zone with well-developed fractures are the ideal locations for ore bodies. Four types of mineralization have been recognized: 1) porphyry-style stockwork gold–iron(copper) ore, 2) skarn-style gold-iron(copper and lead) ore in the near contact zone, 3) strata-bound, lense-type lead–silver–gold ore in the outer contact zone, and 4) distal vein-type gold–lead–silver ore. Supergene processes led to the formation of oxide ore, such as the weathered and accumulated gold–iron ore, the strata-bound fracture oxide ore, and the structure-controlled vein-type ore. Most of these ore deposits are distributed along the axis of the depressed basin, with the hypogene ore controlling the shape and characteristics of the oxide ore. This study provides critical geology understanding for mineral prospecting scenarios. 展开更多
关键词 porphyry-skarn type quartz syenite porphyries ore-controlling factors Beiya goldpolymetallic deposit northwestern yunnan province
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Geochemistry and Zircon U–Pb age of the Yao'an pseudoleucite porphyry,Yunnan Province,China 被引量:10
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作者 Chundi Sun Peng Wu +4 位作者 Die Wang Shenjin Guan Xiaojun Jiang Longyan Jiang Longyan Wang 《Acta Geochimica》 EI CAS CSCD 2017年第2期316-328,共13页
The Yao'an Pb–Ag deposit, located in the Chuxiong Basin, western Yangtze Block, is an important component of the Jinshajiang–Ailaoshan alkaline porphyry–related polymetallic intrusive belt. This complex suite o... The Yao'an Pb–Ag deposit, located in the Chuxiong Basin, western Yangtze Block, is an important component of the Jinshajiang–Ailaoshan alkaline porphyry–related polymetallic intrusive belt. This complex suite of rock bodies includes a vein of pseudoleucite porphyry within deposits of syenite porphyry and trachyte.The pseudoleucite is characterized by a variable greyish,greyish-white, and greyish-green porphyritic texture. Phenocrysts are mainly pseudoleucite with small amounts of alkali feldspar and biotite. In an intense event, leucite phenocrysts altered to orthoclase, kaolinite, and quartz.Both the pseudoleucite porphyry and the syenite porphyry samples were typical alkali-rich, K-rich, al-rich rocks with high LaN/YbNratios; enriched in light rare earth elements and large-ion lithophile elements, and depleted in high field strength elements; and with strongly negative Ta, Nb, and Ti(TNT) anomalies and slightly negative Eu anomalies—all characteristics of subduction-zone mantle-derived rock.We obtained a LA-ICP-MS zircon U–Pb age of 34.1 ± 0.3 Ma(MSWD = 2.4), which is younger than the established age of the Indian and Eurasian Plate collision.The magma derived from a Type-II enriched mantle formed in a post-collisional plate tectonic setting. The geochemical characteristics of the Yao'an pseudoleucite porphyry are powerful evidence that the porphyry'sdevelopment was closely linked to the Jinshajiang–Ailaoshan fault and to the Indian-Eurasian collision. 展开更多
关键词 GEOCHEMISTRY U-Pb age Pseudoleucite porphyry Pb-Ag deposit Yao'an yunnan province
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ISSR Analysis on Genetic Diversity of the 34 Populations of Oryza meyeriana Distributing in Yunnan Province,China 被引量:6
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作者 WAN Ya-tao A Xin-xiang +4 位作者 FAN Chuan-zhang Xu Fu-rong YU Teng-qiong TANG Cui-feng DAI Lu-yuan 《Rice science》 SCIE 2008年第1期13-20,共8页
The genetic diversity of the 34 populations of wild rice Oryza meyeriana Baill. distributed in Yunnan Province, China was analyzed using 13 inter-simple sequence repeat (ISSR) markers. A total of 168 bands were ampl... The genetic diversity of the 34 populations of wild rice Oryza meyeriana Baill. distributed in Yunnan Province, China was analyzed using 13 inter-simple sequence repeat (ISSR) markers. A total of 168 bands were amplified, of which 135 polymorphic bands were discovered and the percentage of polymorphic bands (PPB) was 80.36%. A genetic diversity was revealed as Nei's gene diversity (H) = 0.2666 and Shannon information index (I) = 0.4028 at population level. The 34 populations were divided into different groups based on administrative regions, latitude and longitudes, river areas, altitudes of their origins, and their indexes such as Na (number of alleles), Ne (effective number of alleles), H, I and PPB were calculated. Richer genetic diversity was found in the wild rice populations distributed in Simao Prefecture than that in Lingcang Prefecture or Xishuangbanna Prefecture whereas the least genetic diversity was in Baoshan Prefecture or Dehong Prefecture. Rich genetic diversity was also discovered in the wild rice populations originated from higher than 710 m altitude around the middle and lower reaches of the Lancang River belonging to the Pacific Ocean drainage system. The 34 populations could be classified into two groups, one group covered the wild rice distributing in Simao Prefecture only while the other group covered ones in Lingcang, Xishuangbanna and Dehong Prefectures. The issue on how to effectively conserve the wild rice germplasm was discussed. 展开更多
关键词 Oryza meyeriana POPULATIONS genetic diversity inter-simple sequence repeat marker yunnan province
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Study on the Countermeasures of Drought Control and Disaster Release Based on Humanland Relationship——A Case Study in Yunnan Province
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作者 王保顺 马显光 +2 位作者 冯敏 魏蕾 杨焰 《Agricultural Science & Technology》 CAS 2015年第1期25-30,共6页
Drought, one of the major natural disasters, has attacked Yunnan frequently in recent years, seriously undermining the sustainable development of society and economy and ecological civilization construction. As to the... Drought, one of the major natural disasters, has attacked Yunnan frequently in recent years, seriously undermining the sustainable development of society and economy and ecological civilization construction. As to the series of drought, this study has expounded the necessity and urgency of human-land relationship regulation in drought control and disaster release, from the aspect of human factorsthe inharmonious relationship between human and land. Based on that, the main countermeasures of drought control and disaster release have been further explored, in order to provide references for the future drought control and disaster release in Yunnan. 展开更多
关键词 Drought control and disaster release Human-land relationship COUNTERMEASURES yunnan province
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