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The foundation of “The Max Area Pattern” and Its Training Significance
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作者 Yi Xu 《Open Journal of Applied Sciences》 2012年第4期159-165,共7页
by reference and simplifying the volume expressions of Barrel Theory, this paper puts forward the Double Bottleneck Concept, the Weights of plate as well as the K-value concept on the flex coefficient of the items ref... by reference and simplifying the volume expressions of Barrel Theory, this paper puts forward the Double Bottleneck Concept, the Weights of plate as well as the K-value concept on the flex coefficient of the items reflecting the comparative needing of the factors. It also advances the automatic arrangement on the position of each item and the Max Area Pattern representing the athletic diathesis and ability. It also analysis training pattern in different time-limitation by the Max Area Pattern based on the concept of Balanced-Development. 展开更多
关键词 the MAX area pattern the Double BOTTLENECK Concept the FLEX coefficient the Balanced-Development time-limitation
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Space Pattern of Rural Leisure Tourism Development in Southwest Minority Area——A Case Study of Ethnic Minority Area in Southeast Chongqing
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作者 陶少华 《Journal of Landscape Research》 2010年第8期81-83,共3页
On the basis of analysis of current research documents on rural leisure tourism, taking ethnic minority area of Southeast Chongqing for example, the paper expounded ecology, culture, authenticity and uniqueness of rur... On the basis of analysis of current research documents on rural leisure tourism, taking ethnic minority area of Southeast Chongqing for example, the paper expounded ecology, culture, authenticity and uniqueness of rural leisure tourist resources in ethnic minority area, and city-dependent, scenic area-dependent, traffic route-dependent and remote characteristic village type of space pattern. 展开更多
关键词 Rural LEISURE tourism ETHNIC MINORITY area of SOUTHEAST Chongqing Resources feature SPACE pattern
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Analysis of the Ecological Migration Pattern in Ethnic Minority Areas——A Case Study of Ningxia Hui Autonomous Region 被引量:4
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作者 ZHANG Yun-yan School of Politics and Law,Ningxia University,Yinchuan 750021,China 《Asian Agricultural Research》 2011年第8期85-89,共5页
By taking Ningxia Hui Autonomous Region as an example,this paper analyzes the ecological migration pattern in ethnic minority areas.The basic patterns of development for poverty relief in Ningxia are in-situ migration... By taking Ningxia Hui Autonomous Region as an example,this paper analyzes the ecological migration pattern in ethnic minority areas.The basic patterns of development for poverty relief in Ningxia are in-situ migration and new area development pattern.The new area development pattern includes three types,namely small town development pattern around urban radiation districts,urban labor migration pattern,and large-scale ecological migration pattern.Finally,successful experience of ecological migration in Ningxia is summarized.First,scientific industrial planning shall be made on the basis of proper selection of ecological migration location in immigrant settlement regions.Second,scientific and comprehensive ecological migration policies should be formulated. 展开更多
关键词 ETHNIC MINORITY areas ECOLOGICAL MIGRATION pattern
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Land Use Pattern Analysis of Hilly Areas in Beijing Based on Case Study 被引量:1
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作者 LIU Di YAO Ye CHEN Jiaobin 《Journal of Landscape Research》 2013年第Z1期1-6,共6页
In view of the population explosion in urban districts of Beijing City, limited land resources fail to meet needs of citizens, thus it is imperative to plan land uses of its hilly areas reasonably, avoid urban sprawl ... In view of the population explosion in urban districts of Beijing City, limited land resources fail to meet needs of citizens, thus it is imperative to plan land uses of its hilly areas reasonably, avoid urban sprawl and figure out the way of sustainable development. Through analyzing land use patterns of hilly areas in Hong Kong and Los Angeles, it is to explore valuable experience for the development of hilly areas in Beijing. 展开更多
关键词 BEIJING HILLY area LAND USE pattern EXPERIENCE
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DISTRIBUTION PATTERNS OF LEAF AREA INDEX FOR MAJOR CONIFEROUS FOREST TYPES IN CHINA 被引量:4
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作者 Luo Tianxiang Li Wenhua Zhao Shidong Commission for Integrated Survey of Natural Resources, CAS, Beijing 100101 The People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第4期61-73,共13页
Leaf area index (LAI) of natural vegetation is recognized as the most important variable for measuring vegetation structure over large areas, and for relating it to energy and mass exchange, which has been successfull... Leaf area index (LAI) of natural vegetation is recognized as the most important variable for measuring vegetation structure over large areas, and for relating it to energy and mass exchange, which has been successfully estimated from satellite resolution sensors. In this paper, according to the statistical analysis based on a lot of forest plots, the mathematical models of LAI distribution patterns in the hydro thermal spaces for five coniferous forest types in China were established. For the cold temperate larch forests growing in the dry and cold climate, their LAI increases with the increasing of warm index and precipitation in the way of hyperbolic quadratic surface. For the cold temperate spruce fir forests and temperate Pinus tabulaeformis forests, their LAI is negatively related to the annual mean air temperature in the way of the natural exponential curve, in order to adapt to the water oppressed environments. For the subtropical Pinus massoniana forests and Cunninghamia lanceolata forests growing in the warm and moist climate, their LAI is related to the annual mean air temperature in the way of the parabolic quadratic curve. 展开更多
关键词 leaf area index hydro thermal space distribution pattern.
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A study on zooplankton distribution patterns and indicator species in Kuroshio upstream area and adjacent East China Sea 被引量:4
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作者 He Dehua, Wang Chunsheng, Liu Hongbin and Yang Guanming( Received July 9, 1990 accepted November 12, 1990) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第2期237-254,共18页
On the basis of the data of zooplankton biomass and three major taxa—— Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of... On the basis of the data of zooplankton biomass and three major taxa—— Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of zooplankton in the Kuroshio and adjacent waters of the East China Sea are preliminarily studied. The results are as follows:The horizontal distribution of zooplankton biomass and the abundance of copepods, chaetognaths and siphonophores arecurred in the continent area northwest of Taiwan and the south-centre section of the East China Sea continent, which are the mix front of different waters. Zooplankton in the water area inside of Ryukyu Islands presented low abundance and high diversity. There are clear seasonal variations in zooplankton biomass and abundance in the study area. The strength or weakness of different water masses and fronts is the basic reason for the variations of zooplankton biomass and abundance.The species composition of zooplankton in the study area is complex and varies, however, the tropic oceanic species predominates overwhelmingly. The distribution of different ecotype species evidences the distribution of different water masses and the state of mixture. The indicator species of each water mass are listed in the paper so as to provide grounds for the variation of currents in the Kuroshio area.The temperature and salinity of sea water are important factors affecting zooplankton distribution, composition and diversity , however the role of salinity is major. With the replacement of one season by another, the correlative levels of temperature and salinity to various zooplankton taxa are more or less significant. 展开更多
关键词 A study on zooplankton distribution patterns and indicator species in Kuroshio upstream area and adjacent East China Sea area
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Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years 被引量:7
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作者 HUANG Zhiqin 1,2,3 , ZHOU Wancun 1 ,ZHOU Jieming 4 , ZHU Mingcang 3,5 1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences , Chengdu 610041, Sichuan, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China +2 位作者 3. Sichuan Institute of Land Resource Management, Chengdu 610041, Sichuan , China 4. Department of Resources and Environment Science, Sichuan Normal University , Chengdu 610061, Sichuan, China 5. College of Information Engineering, Chengdu University of Technology, Chengdu 610059, Sichuan, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期910-914,共5页
The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS (Remote Sense) and GIS (Geography Information System). Based on... The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS (Remote Sense) and GIS (Geography Information System). Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that: in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change (LUCC). The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index. 展开更多
关键词 the Three Gorges Reservoir area land use/cover change landscape pattern.
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Child Mortality Patterns in Rural Areas of Anhui and Henan Provinces in China, 1990
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作者 JIN SHUI-GAO YANG GONG-HUAN +6 位作者 EBOS WANG JIA LUO JU-HUA YANG JIE MA EN-Bo TONG MIN-XIN DJAMISON 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1998年第3期264-276,共13页
County-based IMR and U5MR in Anhui and Henan provinces in China were estimated and analyzed by using the 1990 Census Data. Census was conducted on July 1,1990, the number of deaths only occurred in the first half year... County-based IMR and U5MR in Anhui and Henan provinces in China were estimated and analyzed by using the 1990 Census Data. Census was conducted on July 1,1990, the number of deaths only occurred in the first half year of 1990 was collected. In order to obtain the total population and total number of deaths in the same year, the total number of deaths in each eqersex group for the whole 1990 was then estimated by taking the death number in the first half of 1990 as the base and multiplying a coefficient, which varied in different age-sex-region groups. Two major adjustments for some possible underreporting cases in female birth and infant death were made. If the sex ratio at age 0 in some counties was beyond 1. 2, then it was taken as 1. 15 for rural counties and 1.10 for urban cities, which were the estimates of sex ratios for the children at ape 5 in the national 1% Population Sampling Survey in 1995. The adjustment for IMR were made by comparing the segment of the county lift table from age 15 through 59 with that from the same age groups in the international and Chinese Model Life Tables. The IMR in the county life table would be substituted by the one in the closest Model Life Talbe, if it was less than in the latter.The findings of the analysis may be summarized as fol1ows: (i) Total county-based IMR and U5MR were 33. 4 Per 1000 and 41. 4 per 1000 respectively, with great variations between urban cities (25. 4 per 1000 for IMR and 31. 4 per 1 000 for U5MR) and rural counties (35. 1 Per 1000 for IMR and 43. 6 per 1000 for U5MR). There were also sighficant differences in child mortality between nationally identified Poor counties and other counties in rural areas. In the opr counties the total IMR was 40. 7 per 1 000 living births in average while in non-opr counties it was only 33. 2 per 1000 in average (P < 0.05). The U5MR in opr counties was 25 percent higher than in non-opr counties (51. 5 vs 40. 9 Per 1 000 living births).(ii) Statistically significant correlation between child mortality and socio-economic variables was revealed from the data set, among which gross social economic products per capita was found to have the strongest relationship with child mortality. The neqative correlation was found between child mortality and a set of socalled' rich' variables including the gross social products, gr-oss agricultural products, gna industrial products and the proportions of high-educated population at county level, whereas the poSitive correlation was found between child mortality and a set of'poor' variables, such as proportions Of residents with lower 1evel of education and illiteracy rate.(iii) thfferences in child mortality between these two provinces were found, which were identical to the trends of differences in socio-economic indicators between them.tower child mortality proved to be associated with better socio-economic conditions(higher per capita products, higher proPortions of residents with higher level of education, lower proportion of less educated people and illiteracy) in province Henan. 展开更多
关键词 ZHANG Child Mortality patterns in Rural areas of Anhui and Henan Provinces in China
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Phase Identification Using Series of Selected Area Diffraction Patterns and Energy Dispersive Spectrometry within TEM
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作者 Kun-Lin Lin 《Microscopy Research》 2014年第4期57-66,共10页
Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns... Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns (SADPs) are crystallographic data that can be obtained using a TEM in-strument. Conventional identification through SADP/TEM is tricky and tedious, thereby increasing the difficulty of phase identification. To establish a procedure for phase identification of known and unknown phases, in this study we examined two samples: one, a known phase, was Si with alignment;the other, unknown, was the TixOy phase at the 96.4Au-3Ni-0.6Ti interlayer/ yttria-stabilized zirconia (YSZ) interface of a steel/96.4Au-3Ni-0.6Ti interlayer/YSZ joint. The procedures for phase identification of the known and unknown phases are described herein using a series of SADPs and energy dispersive spectrometry within TEM that would be useful for general researchers. 展开更多
关键词 Phase Identification Transmission Electron MICROSCOPY SELECTED area DIFFRACTION pattern Energy DISPERSIVE Spectroscopy
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Patterns of Poverty Alleviation in Mountain Areas
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作者 Li Yining 《China Population Today》 1996年第4期5-5,共1页
PatternsofPovertyAlleviationinMountainAreas¥LiYining(ProfessorLiYiningisawell-knowneconomistwithPekingUniver... PatternsofPovertyAlleviationinMountainAreas¥LiYining(ProfessorLiYiningisawell-knowneconomistwithPekingUniversity.)Basedonthef... 展开更多
关键词 patterns of Poverty Alleviation in Mountain areas
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Analysis of Landscape Patterns and the Trend of Forest Resources in the Three Gorges Reservoir Area
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作者 Wei Wang Ying Pu 《Journal of Geoscience and Environment Protection》 2018年第5期181-192,共12页
In this paper, first, based on landscape ecology theories, we respectively selected indexes from 4 aspects, area, edge, shape, and density, of the landscape type to describe the status of forest landscape patterns, an... In this paper, first, based on landscape ecology theories, we respectively selected indexes from 4 aspects, area, edge, shape, and density, of the landscape type to describe the status of forest landscape patterns, and we established the stability index of landscape pattern (LSBI). Then, based on geo-statistical theories, we divided the forest in the reservoir area into 3990 grids of 4 km × 4 km using network technology and employing ordinary Kriging modelling to make trend surface analyses of the forest resources in the reservoir area. Finally, based on statistics principles, we used sampling theory to systematically extract 227 samples to obtain 7 periods of remote-sensing data from 1990a to 2012a. Then, we classified and extracted the forest in the sampling area using remote sensing, and we analysed each result with an Autoregressive Integrated Moving Average Model (ARIMA) time-series model. The results indicated the following: 1) the landscape structure of the reservoir area was primarily needle-leaved forest, broad-leaved forest and bush forest, and the mixed stands and bamboo stands were secondary;2) the difference of the forest landscape pattern stability in the reservoir area, in all directions, was not significant, but the southern region was slightly more stable;and 3) the stability of the forest landscape pattern in the reservoir area increased from 1990a to 2012a. It kept increasing until 2016a. This study provides a theoretical basis for the reasonable management and decisions about the forest resources in the Three Gorges Reservoir Area. Meanwhile, it also explores methods for relevant research and has practical significance. 展开更多
关键词 Three Gorges RESERVOIR area FOREST RESOURCES LANDSCAPE pattern TREND ANALYSIS
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Responses of differences in iron and manganese partitioning patterns within and among organs on legume biomass in limestone and sandstone areas 被引量:1
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作者 Hechun PIAO Congqiang LIU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期169-170,共2页
关键词 豆科作物 石灰石 砂岩 土壤 植物
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Prediction of Landscape Pattern of Soft Sandstone Area (SSA) after Seabuckthorn Planting 被引量:1
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作者 Jianzhong Hu 《American Journal of Plant Sciences》 2012年第1期171-176,共6页
As a pioneer plant in the gully slopes in the Soft Sandstone Area (SSA) for eco-economical consideration, ten years (1999-2008) planting of seabuckthorn has made 1642.83 km2, or 9.84%, of the total area of SSA change ... As a pioneer plant in the gully slopes in the Soft Sandstone Area (SSA) for eco-economical consideration, ten years (1999-2008) planting of seabuckthorn has made 1642.83 km2, or 9.84%, of the total area of SSA change into seabuckthorn coverage. In SSA the landscape has been divided into 9 types, such as seabuckthorn, sand, water, settlement, bush, open vegetation, forest, grassland and unused land. Seabuckthorn type is separated from the bush type for estimating the role of seabuckthron planting. By means of the Markov model, the developing trends of every landscape types can be determined to support the seabuckthorn project which influences the landscape pattern deeply in SSA. The prediction shows that the optimism ratio of seabuckthorn in the future should be 10.21%, the open vegetation 32.25%, and the forest percentage under 10%, which is a very wise tactics to avoid the serious death of various vegetations in SSA to match the local arid eco-environment. 展开更多
关键词 Landscape pattern MARKOV Model PREDICTION SEABUCKTHORN Soft SANDSTONE area (SSA)
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The Characteristics of Soil Nutrients in Terracing Land under Different Land Use Patterns in Three Gorges Reservoir Area
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作者 Guojian CHEN Chunli LI +3 位作者 Juanjuan LI Liangyu LIAO Jie WEI Peixia LI 《Asian Agricultural Research》 2017年第3期89-92,共4页
In this study,taking the typical terracing land in Wushan County of Chongqing Municipality for example,we study the distribution of soil nutrients in the terracing land under different land use patterns in Three Gorge... In this study,taking the typical terracing land in Wushan County of Chongqing Municipality for example,we study the distribution of soil nutrients in the terracing land under different land use patterns in Three Gorges Reservoir Area. We conduct field survey and sampling on three different land use patterns( cash crop land,food crop land and abandoned land),and do the indoor experimental analysis of soil nutrient indicators. The results indicate that there is significant or very significant impact on soil nutrients under different land use patterns. The content of soil organic matter declines in sequence from abandoned land,food crop land to cash crop land; the content of soil N declines in sequence from cash crop land,abandoned land to food crop land; the content of soil P declines in sequence from cash crop land,food crop land to abandoned land; the content of soil K declines in sequence from abandoned land,cash crop land to food crop land. The result is in close relation to land use patterns,human cultivation activity,land disturbance and application of fertilizer. 展开更多
关键词 Three Gorges Reservoir area Terracing land Land use patterns Soil nutrients
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基于MGWR模型的太行山脉自然保护地空间格局评价及空间优化 被引量:3
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作者 王成武 罗俊杰 +2 位作者 汪宙峰 张荞 谢亮 《生态学杂志》 北大核心 2025年第1期325-336,共12页
太行山脉自然保护地在生态系统修复、生物多样性保护和自然遗迹保护等方面发挥了重要作用,承担了中国华北地区生态文明建设的重要功能。本研究以太行山脉300个国家级及省市级自然保护地为对象,通过莫兰指数、多距离空间聚类、核密度分... 太行山脉自然保护地在生态系统修复、生物多样性保护和自然遗迹保护等方面发挥了重要作用,承担了中国华北地区生态文明建设的重要功能。本研究以太行山脉300个国家级及省市级自然保护地为对象,通过莫兰指数、多距离空间聚类、核密度分析等空间分析方法研究自然保护地数量和面积的空间格局,借助多尺度地理加权回归模型(MGWR)对影响因素进行空间异质性分析,为自然保护地空间优化提供科学依据。结果表明:(1)自然保护地数量在整体上显著聚集分布(I_(全)=0.9707)。湿地公园(I_(湿)=0.7130)和风景名胜区(I_(风)=0.5031)较其他自然保护地聚集程度更强。(2)自然保护地面积在空间上形成“双核一带”聚集格局。具体表现为以保定市(涞水县、易县)为中心的北太行东北高密度核心区、以石家庄市(灵寿县)、忻州市(五台县)为中心的西太行西北高密度核心区和以邢台县-壶关县-济源市为核心串联而形成的核心地带。(3)自然保护地面积空间格局的影响因素存在显著空间异质性。植被覆盖率和路网密度的正面影响最强,而海拔和建设用地面积的负面影响最强。因此,在自然保护地规划和建设中应区别各类保护地的属性特点,在强调提升自然保护地植被覆盖率的同时,对于城市化地区的自然保护地要关注路网密度的积极影响和建设用地的抑制作用,在高海拔地区规划与设立自然保护地要注意数量和规模适度。 展开更多
关键词 自然保护地 空间分异 格局优化 多尺度地理加权回归模型 太行山脉
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Particle Size Characteristics of Soil in Karst Area with Different Land Use Pattern—A Case Study of Shuifang Spring,Jinfo Mt.,Chongqing
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作者 Yingqin Wang,Linli Li School of Geographical Sciences,Southwest University,Chongqing 400715,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期87-87,共1页
This paper tried to analyze the particle size characteristics of the soil samples in Shuifang Spring catchment area,Jinfo Mt.,Chongqing with different land use patterns that are horse race grassland, rhododendron bush... This paper tried to analyze the particle size characteristics of the soil samples in Shuifang Spring catchment area,Jinfo Mt.,Chongqing with different land use patterns that are horse race grassland, rhododendron bush,bamboos,and the grassland near the Shuifang spring.The different land usepattern in karst area is of great affection to the particle size characteristics of soil.The median diameter of the karst surface layer soil becomes gradually smaller and smaller in following sequence:horse race grassland,grassland near the Shuifang Spring, 展开更多
关键词 particle size CHARACTERISTICS of SOIL land use pattern KARST Shuifang SPRING CATCHMENT area
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Paleogene Tectonic Evolution Controls on Sequence Stratigraphic Patterns in the Central Part of Deepwater Area of Qiongdongnan Basin, Northern South China Sea 被引量:17
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作者 Guangzeng Song Hua Wang +6 位作者 Huajun Gan Zhipeng Sun Xiaolong Liu Meng Xu Jinfeng Ren Ming Sun Di Sun 《Journal of Earth Science》 SCIE CAS CSCD 2014年第2期275-288,共14页
In active rift basins, tectonism is extremely important for sequence stratigraphic patterns, affecting both the sequence architecture and internal makeup. Sequence stratigraphic framework of a Paleogene rift successio... In active rift basins, tectonism is extremely important for sequence stratigraphic patterns, affecting both the sequence architecture and internal makeup. Sequence stratigraphic framework of a Paleogene rift succession in Qiongdongnan Basin, northern South China Sea, was built using seismic profiles, complemented by well logs and cores. One first-order and three second-order sequences were identified on the basis of basin-scale unconformities, and seven third-order sequences are defined by unconformities along the basin margins and correlative conformities within the central basin. Through unconformity analysis and backstripping procedure, the Paleogene synrift tectonic evolution of deep- water area of Qiongdongnan Basin was proved to be episodic, which can be divided into rifting stage-I, rifting stage-II and rifting stage-III. Episodic rifting resulted in the formation of various types of struc- tural slope break belts, which controlled different architectures and internal makeup of sequences. This study enhances the understanding of the control of tectonic evolution on sequence stratigraphic pat- terns and establishes relevant patterns in a typical rift basin, and further proposes the favorable sand- stone reservoirs developing in different sequence stratigraphic patterns, which will be pretty helpful for subtle pool exploration in deepwater area of petroliferous basins. 展开更多
关键词 South China Sea deepwater area tectonic evolution structural slope break belt se-quence stratigraphic pattern.
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Valley Density Evaluation and Typical Development Pattern in Mountainous Areas of Beijing
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作者 MU Song-lin ZHANG Yi-feng +3 位作者 WANG Kai-yong TANG Cheng-cai WANG Ling-en LIU Yu 《Asian Agricultural Research》 2012年第12期33-37,48,共6页
Based on geographical differences and space differentiation, valley economy is a new pattern and new perspective for the development of mountainous areas, integrating ecological protection, industrial nurture, and vil... Based on geographical differences and space differentiation, valley economy is a new pattern and new perspective for the development of mountainous areas, integrating ecological protection, industrial nurture, and village integration. On the basis of natural and geographical differentiation of valley, we give an overview of the spatial distribution of valley in mountainous areas of Beijing and spatial difference in valley density, and sum up the typical development pattern of valley economy, using DEM data. The results show that the spatial distribution of valley presents an asymmetric shape of inverted V or branch; Miyun, Yanqing, and Changping have high valley density, while Pinggu, Fangshan and Mentougou have low valley density; there is a significant positive relationship between valley density and the spatial distribution of river and reservoir. The development pattern of valley economy is divided into five types: leisure and high-end upgrade-based pattern, ecological development and transition demonstration-based pattern, folk culture and creation-driven pattern, scenic spots-driven and valley-linked pattern and leisure agriculture and specialty-led pattern. 展开更多
关键词 Mountainous areas of BEIJING VALLEY DENSITY VALLEY
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老挝铜资源成矿规律与基于机器学习的远景预测
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作者 张必敏 王学求 +11 位作者 周建 王玮 刘汉粮 刘东盛 Sounthone LAOLO Phomsylalai SOUKSAN 谢淼 董春放 柳青青 鲁岳鑫 王浩楠 贺彬 《地学前缘》 北大核心 2025年第1期61-77,共17页
老挝处于特提斯成矿域南东段,具有丰富的矿产资源,但其地质工作基础薄弱,厘定矿产资源成矿规律并开展远景区预测是老挝在重点区实现找矿突破的有效途径。老挝1∶1000000国家尺度地球化学填图由中老双方合作完成,为其矿产资源和环境评价... 老挝处于特提斯成矿域南东段,具有丰富的矿产资源,但其地质工作基础薄弱,厘定矿产资源成矿规律并开展远景区预测是老挝在重点区实现找矿突破的有效途径。老挝1∶1000000国家尺度地球化学填图由中老双方合作完成,为其矿产资源和环境评价提供了高质量的地球化学基础数据和图件。本文主要利用国家尺度地球化学填图数据,结合老挝已发现矿产成矿规律,利用机器学习技术,开展铜资源远景区预测。研究结果表明:(1)老挝铜矿床的形成明显受到构造-岩浆-沉积作用控制,铜矿床主要类型有斑岩型、夕卡岩型、热液型和砂岩型。(2)老挝全国水系沉积物中铜含量为1.20~459.00μg/g,平均值为21.96μg/g,中位值为16.50μg/g,在7个三级大地构造单元中,长山地块和哀牢山—马江等3个缝合带的平均值高于其他几个构造单元,地球化学图显示铜在老挝分布不均匀,存在多个大面积分布的高背景区和异常区。(3)构建了包括单元素异常、矿化元素组合异常、指示中酸性岩体元素组合、控矿构造分布、碳酸盐岩和碎屑岩分布等要素的老挝铜矿多源信息定量信息预测模型。(4)利用随机森林成矿预测方法,共圈定9个成矿远景区,具有寻找斑岩型和夕卡岩型等类型铜矿找矿前景。 展开更多
关键词 远景区预测 机器学习 铜成矿规律 地球化学填图 老挝
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东营凹陷滨三区滨348块火成岩岩相分布研究
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作者 王跃刚 吕维刚 陈志湘 《复杂油气藏》 2025年第1期38-44,共7页
以东营凹陷滨三区滨348区块沙三下(沙河街组沙三段下部)火成岩为研究对象,根据测井、钻录井、岩心以及开发地震资料等综合分析,识别火成岩不同岩性、划分岩相,得出岩相分布规律,并建立了火山模式。通过研究分析,得出火成岩岩性以玄武岩... 以东营凹陷滨三区滨348区块沙三下(沙河街组沙三段下部)火成岩为研究对象,根据测井、钻录井、岩心以及开发地震资料等综合分析,识别火成岩不同岩性、划分岩相,得出岩相分布规律,并建立了火山模式。通过研究分析,得出火成岩岩性以玄武岩为主,岩相以溢流相为主,并发育火山口相、火山通道相、侵入相等其他岩相。基于裂隙式喷发模式建立了串珠状裂隙式喷发和点状裂隙式喷发两种喷发模式。 展开更多
关键词 火成岩 火山岩相 火山模式 滨三区
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