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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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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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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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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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以发展和安全统筹推进边疆地区现代化——深入学习领会“十五五”规划建议
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作者 孙久文 《西北民族大学学报(哲学社会科学版)》 北大核心 2026年第1期7-11,共5页
边疆地区在基础设施建设、特色产业培育(如新能源、旅游业)以及对外开放等领域取得了显著成就,但仍面临经济水平偏低、人才短缺、生态压力大、安全形势复杂等多重挑战。基于总体国家安全观,该区域要以发展和安全统筹推进现代化:健全边... 边疆地区在基础设施建设、特色产业培育(如新能源、旅游业)以及对外开放等领域取得了显著成就,但仍面临经济水平偏低、人才短缺、生态压力大、安全形势复杂等多重挑战。基于总体国家安全观,该区域要以发展和安全统筹推进现代化:健全边疆治理体系、强化风险防控、深化“兴边富民”战略;同时挖掘边疆独特优势(区位、资源储备、特色经济、政策倾斜),将其转化为发展动能。“十五五”时期,边疆地区需发挥“双循环”枢纽功能:建设国际物流与供应链枢纽、扩大跨境数字金融服务、打造能源资源基地、发展特色文旅经济,实现从地理边缘区到双向开放增长极的转变,筑牢发展和安全屏障。 展开更多
关键词 “十五五”规划 边疆地区 中国式现代化 新安全格局 新发展格局
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贵州凯里地区热液型重晶石矿床地质特征与分布规律及成因分析
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作者 张锡贵 代胜 +1 位作者 何善立 石庆鹏 《矿产综合利用》 2026年第1期22-30,共9页
【目的】贵州凯里地区作为贵州热液型重晶石矿床主要分布区之一,其热液型重晶石矿床具有重要的经济价值和科学研究意义。然而,关于该区热液型重晶石矿床的地质特征及分布规律研究相对较少,缺乏系统性和全面性。【方法】本文主要通过野... 【目的】贵州凯里地区作为贵州热液型重晶石矿床主要分布区之一,其热液型重晶石矿床具有重要的经济价值和科学研究意义。然而,关于该区热液型重晶石矿床的地质特征及分布规律研究相对较少,缺乏系统性和全面性。【方法】本文主要通过野外调查,结合前人对该类型重晶石矿床的研究成果,系统分析了矿床的地质特征,采用类比法从成矿时间、空间分布、控矿因素、成矿物质来源等方面揭示凯里地区热液型重晶石矿床的分布规律及成矿机制。【结果】凯里地区热液型重晶石矿体主要产于奥陶系桐梓组和红花园组地层中发育的张性断层破碎带、层间断层破碎带及节理裂隙密集带内,严格受构造和地层控制。【结论】此类重晶石矿床的形成塑造了一个“生、运、储、盖”组合的成矿系统。本次研究成果为该地区重晶石的勘查与开发提供科学依据。 展开更多
关键词 热液型重晶石 矿床地质特征 分布规律 控矿因素 凯里地区
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黄土高原2000-2020年土地利用景观格局时空演变研究——以董志塬区域为例
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作者 谢晓玲 马睿苑 赵江亭 《国土与自然资源研究》 2026年第2期10-14,共5页
董志塬区域是典型的生态脆弱区,在国家实施了一系列的生态修复与治理项目后,该地区的土地利用方式也随之改变,掌握该地区土地利用景观格局的时空演变规律能够推动该区域的生态文明建设,并进一步实现其可持续发展目标,也为该地区未来的... 董志塬区域是典型的生态脆弱区,在国家实施了一系列的生态修复与治理项目后,该地区的土地利用方式也随之改变,掌握该地区土地利用景观格局的时空演变规律能够推动该区域的生态文明建设,并进一步实现其可持续发展目标,也为该地区未来的土地利用规划提供了有力的参考依据,有助于制定更为科学、合理的土地利用策略。利用ArcGIS软件对董志塬四期土地利用数据进行处理,对该地区自2000年以来的土地利用面积变化、类型转换以及动态演变趋势深入分析,结合Fragstats软件,系统计算并分析了该区域的景观格局指数。结果表明,董志塬区域生态治理与修复措施在近20年间取得了一定成效,未来在实施生态修复工程时需要因地制宜,考虑该区域特殊的地理环境等因素,有针对性的提出和实施各项修复措施。 展开更多
关键词 董志塬 土地利用 景观格局 生态脆弱区 黄土高原
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母亲孕期体重增长模式对儿童0~3岁体质量指数轨迹的影响
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作者 褚光萍 魏薇 +3 位作者 陈婷 曹巧璐 许香香 龚甜 《中国儿童保健杂志》 北大核心 2026年第1期23-28,共6页
目的 分析儿童0~3岁体质量指数(BMI)轨迹,探讨孕期体重增长模式对儿童BMI轨迹的影响。方法 选取2021—2022年在苏州市姑苏区分娩的孕妇,追踪其儿童0~3岁时的身高和体重。采用潜类别增长模型构建儿童0~3岁BMI变化轨迹,通过曲线下面积(AUC... 目的 分析儿童0~3岁体质量指数(BMI)轨迹,探讨孕期体重增长模式对儿童BMI轨迹的影响。方法 选取2021—2022年在苏州市姑苏区分娩的孕妇,追踪其儿童0~3岁时的身高和体重。采用潜类别增长模型构建儿童0~3岁BMI变化轨迹,通过曲线下面积(AUC)计算孕妇孕期体重累积AUC和增量AUC。采用logistic回归探讨孕期体重AUC与儿童0~3岁BMI轨迹的关联。结果 共10 590对母婴数据纳入分析。儿童0~3岁BMI轨迹拟合为3类:适宜生长组、先高后降组和快速生长组。以适宜生长组为参考,多因素logistic回归分析显示,与体重累积AUC Q_1组相比,Q_2组(OR=1.26,95%CI:1.04~1.51)、Q_3组(OR=1.28,95%CI:1.07~1.54)、Q_4组(OR=1.38,95%CI:1.15~1.66)均增加儿童BMI先高后降的风险,Q_4组亦增加儿童快速生长的风险(OR=1.24,95%CI:1.05~1.46)。母亲孕期体重增长模式与子代BMI轨迹风险的关联在男女童中存在差异。结论 儿童0~3岁BMI轨迹可分为适宜生长、先高后降和快速生长三组模式,母亲孕期不适宜的体重增长模式会增加儿童0~3岁呈现先高后降和快速生长BMI轨迹的风险。 展开更多
关键词 生长轨迹 孕期体重增长模式 曲线下面积 儿童
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赤水河上游不同利用方式土壤团聚体磷组分对淋溶作用的响应
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作者 冯小纹 孟祥志 +3 位作者 李亦然 王震 王克勤 侯磊 《农业环境科学学报》 北大核心 2026年第2期456-467,共12页
为探明淋溶作用对不同利用方式土壤团聚体磷组分淋失的影响,选取云南赤水河上游龙井小流域的坡耕地、灌木林地、经果林地和人工林地土壤为研究对象,开展室内土柱淋溶试验,分析不同利用方式下土壤团聚体磷组分淋失特征的差异和影响因素,... 为探明淋溶作用对不同利用方式土壤团聚体磷组分淋失的影响,选取云南赤水河上游龙井小流域的坡耕地、灌木林地、经果林地和人工林地土壤为研究对象,开展室内土柱淋溶试验,分析不同利用方式下土壤团聚体磷组分淋失特征的差异和影响因素,并估算全流域磷年均淋失量。结果表明:不同利用方式土壤以大团聚体(>2 mm)为主,占比均>52.06%,全磷(TP)含量呈经果林地(1.98 g·kg^(-1))>灌木林地(1.59 g·kg^(-1))>坡耕地(1.40 g·kg^(-1))>人工林地(0.62 g·kg^(-1))趋势,前三种利用方式受施肥影响,以有机结合态磷(OP)为主(占比46.19%~65.49%),人工林地则以钙结合态磷为主(占比73.11%~86.14%);溶解态磷(SP)是淋滤液中磷的主要形态,坡耕地土壤TP、SP及两者占比显著高于其他利用方式(P<0.05),均值分别为0.10、0.09 mg·L^(-1)和90.00%,累积淋失量(0.1853 mg)是其他利用方式的1.79~1.89倍;人工林地土壤表现为负淋失,磷平均淋失率达-14.23%,团聚体OP升高为主要贡献,其余利用方式土壤磷淋失率范围为50.35%~61.64%,团聚体OP和铁铝结合态磷(Fe/Al-P)为主要淋失形态;团聚体TP和Fe/Al-P含量、土壤结构稳定性、pH及SOM的利用方式差异是影响淋溶作用响应的关键因素,赤水河流域年均磷淋失量达19.13 kg·hm^(-2),坡耕地贡献最大(73.35%),人工林地有阻控效应(-2.69%)。研究表明,施肥活动降低土壤团聚体稳定性是喀斯特地区磷淋失的诱因,退耕还林及植树造林可减少或阻控磷淋失。 展开更多
关键词 喀斯特区域 土壤团聚体 土地利用类型 磷素淋失
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基于多尺度的矿区植被NPP演变特征及影响因子分析
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作者 戴林达 毕银丽 阎跃观 《矿业科学学报》 北大核心 2026年第1期75-89,共15页
煤矿区地表生态受到地形、植被、气象及开采扰动等多种因素时空交织的影响。针对现有植被净初级生产力(NPP)研究多侧重宏观尺度而缺乏精细解析的问题,文中以神东矿区及上湾矿为研究对象,构建“矿区-煤矿-工作面”多级评价单元,结合干旱... 煤矿区地表生态受到地形、植被、气象及开采扰动等多种因素时空交织的影响。针对现有植被净初级生产力(NPP)研究多侧重宏观尺度而缺乏精细解析的问题,文中以神东矿区及上湾矿为研究对象,构建“矿区-煤矿-工作面”多级评价单元,结合干旱半干旱区高密度开采、风沙地貌等生态本地特征,采用优化CASA模型与概率积分法,集成30 m分辨率遥感数据与地表变形参数,系统揭示2000—2023年植被NPP的时空演变规律及多尺度驱动机制。研究结果表明:多尺度下NPP均呈增长趋势(矿区2.8%、煤矿2.9%、工作面3.2%),但工作面尺度受局部采矿扰动呈现阶段性下降;矿区和煤矿尺度NPP受降雨及归一化植被指数(NDVI)主导(r最高0.98),而工作面尺度NPP与地表水平变形显著负相关(r=-0.66),阐明了开采直接物理损伤的微观机制。提出“分区调控”治理策略:矿区尺度需强化气候适应性植被恢复,工作面尺度应优先控制水平变形,并建立采后3年内生态修复窗口期。 展开更多
关键词 煤矿沉陷区 植被NPP 时空演变规律 影响因子分析
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