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Eternal Climate Change Patterns and the Causes and Countermeasures of Global Climate Change
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作者 Cuixiang Zhong 《Journal of Environmental Science and Engineering(B)》 2024年第1期9-20,共12页
It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summari... It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summarized the 24 solar terms by observing the annual activities of the sun for a long time,because they ignored the impact of the activities of the moon on the Earth’s climate change on a small scale,the 24 solar terms they summarized often could not accurately predict the change of the Earth’s climate.Therefore,the author studied the influence of lunar activities on the Earth’s climate change,finds out the law of the influence of lunar activities on the Earth’s climate change on a small scale,and summarizes the eternal climate change pattern determined by the activities of the sun and the moon.In addition,the author also reveals the causes and countermeasures of global warming and the frequent occurrence of extreme weather as well as environmental change. 展开更多
关键词 Eternal climate change patterns global warming extreme weather abrupt environmental changes CAUSES countermeasures.
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BEARING IN MIND MEGATREND FOR PEACE AND DEVELOPMENT AGAINST CHANGING INTERNATIONAL PATTERN
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作者 MA XIAOJUN 《Contemporary World》 2017年第2期7-10,6,共5页
Uncertainties in the International Situation Are on the Increase and Transformation of International Pattern and Order Accelerates and Deepens Since 2016,the world has begun to enter into a historical period of uncert... Uncertainties in the International Situation Are on the Increase and Transformation of International Pattern and Order Accelerates and Deepens Since 2016,the world has begun to enter into a historical period of uncertainty.The fact that the Ukrainian Crisis has dragged on for long and that 展开更多
关键词 US it FORM of that BEARING IN MIND MEGATREND FOR PEACE AND DEVELOPMENT AGAINST changing INTERNATIONAL pattern into is
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Pattern Change and Regional Disparity Tendency of Cultivated Land Use in Jiangsu Province
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作者 金涛 徐舟 《Agricultural Science & Technology》 CAS 2013年第10期1517-1520,1525,共5页
The study has examined the tempo-spatial patterns of cultivated land use change in Jiangsu province. A principal component analysis (PCA) of 18 selected indicators of cultivated land use during the period 1970-2010 ... The study has examined the tempo-spatial patterns of cultivated land use change in Jiangsu province. A principal component analysis (PCA) of 18 selected indicators of cultivated land use during the period 1970-2010 identified 2 main pat- terns of change in planting productivity and economic efficiency. A major shift from production-centered pattern to profit-oriented one occurred in 1984, the time of grain yield surplus and the mitigation of population pressure. In response to the impending Opened Market System, there was a notable tendency of higher efficiency and less productivity since 1997, as well as remarkable regional disparity of cultivated land use change spatially. It revealed a relative decrease in grain cropping share, crop- ping scale and cultivation intensity in South Jiangsu, especially in Tai-Lake region, and the reverse in North Jiangsu. Some suggestions for the future were finally dis- cussed from the above findings. 展开更多
关键词 Cultivated land use pattern change Regional disparity PCA Jiangsu Province
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Impacts of human activity and natural change on the wetland landscape pattern along the Yellow River in Henan Province 被引量:9
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作者 梁国付 丁圣彦 《Journal of Geographical Sciences》 SCIE CSCD 2004年第3期339-348,共10页
By using GIS and remote sensing techniques, the paper discusses how human activities have changed along the Yellow River in Henan province, China and how these altered activities have influenced the wetland landscape ... By using GIS and remote sensing techniques, the paper discusses how human activities have changed along the Yellow River in Henan province, China and how these altered activities have influenced the wetland landscape pattern change from 1987 to 2002. Results show that the total area of the wetland reduces dramatically compared to 1987, the total area of wetland reduces by 19.18%, the number of the patches in 2002 increases by 21.17%, the density increases by 50%, and the total perimeter increases by 1,290,491 m. Disturbed by human activities, landscape diversity index decreases from 1.1740 in 1987 to 0.9803 in 2002. During the last 20 years, the total area of the rice wetland increases, while the others decrease. Among those, the area of the bulrush wetland decreases most. In 1987, it takes 0.5% of the total area, but in 2002, it only takes 0.11%. The interpenetration of human influences on the wetland natural system has been long and close. The impacts of human activities on the spatial pattern of the wetland landscape along the Yellow River in Henan from 1987 to 2002 are great. 展开更多
关键词 landscape pattern change the Yellow River FLOODPLAIN remote sensing
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Regional agricultural landscape pattern changes along the Yellow River in Henan Province from 1987 to 2002 被引量:5
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作者 LIANG Guofu DING Shengyan LI Zhiheng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期415-422,共8页
Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the cha... Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the change of agricultural landscape along the riparian zones is at the top of the agenda for many policy makers and landscape planners. As a basis for conservation management, sufficient information about landscape structure should be provided. In the present study, we reconstructed the former landscape structure and elucidated the changes in landscape patterns during a period of about 15 years. Two sets of maps were used: a landsat-5 TM image (1987) and landsat-7 ETM image (2002). The frequency index, landscape diversity index and landscape fragmentation index were calculated for analyses. The results showed that: (1) the areas of the irrigated land, river, forest and beach landscape classes presented a decreasing trend while the areas of landscape classes of pool, paddy fields, dry land and construction land increased. (2) Disturbed by human activity, landscape diversity index increased but landscape fragmentation index decreased. In short, Human activities have had important influences on agricultural landscape of the riparian zones along the Yellow River in Henan Province. 展开更多
关键词 agricultural landscape landscape pattern change the Yellow River Henan Province
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Characteristics of Temperature Change in China over the Last 2000 years and Spatial Patterns of Dryness/Wetness during Cold and Warm Periods 被引量:10
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作者 Quansheng GE Haolong LIU +2 位作者 Xiang MA Jingyun ZHENG Zhixin HAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第8期941-951,共11页
This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation ... This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation in China has exhibited significant 50–70-yr, 100–120-yr, and 200–250-yr cycles. Results also show that the amplitudes of decadal and centennial temperature variation were 1.3℃ and 0.7℃, respectively, with the latter significantly correlated with long-term changes in solar radiation, especially cold periods, which correspond approximately to sunspot minima. The most rapid warming in China occurred over AD 1870–2000, at a rate of 0.56°± 0.42℃(100 yr)^(-1); however, temperatures recorded in the 20 th century may not be unprecedented for the last 2000 years, as data show records for the periods AD 981–1100 and AD1201–70 are comparable to the present. The ensemble means of dryness/wetness spatial patterns in eastern China across all centennial warm periods illustrate a tripole pattern: dry south of 25°N, wet from 25°–30°N, and dry to the north of 30°N. However, for all centennial cold periods, this spatial pattern also exhibits a meridional distribution. The increase in precipitation over the monsoonal regions of China associated with the 20 th century warming can primarily be attributed to a mega El Nino–Southern Oscillation and the Atlantic Multidecadal Oscillation. In addition, a significant association between increasing numbers of locusts and dry/cold conditions is found in eastern China. Plague intensity also generally increases in concert with wetness in northern China, while more precipitation is likely to have a negative effect in southern China. 展开更多
关键词 temperature change dry-wet spatial pattern cold and warm periods last 2000 years China
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Distribution Orientation and Driving Mechanism of Geographical Pattern Change of China′s Banking Industry 被引量:1
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作者 CHEN Dong FAN Jie 《Chinese Geographical Science》 SCIE CSCD 2011年第5期563-574,共12页
By analyzing the relationship among government, market driving forces, distribution orientation of banking industry, service opportunity equality and spatial patterns, this paper proposes that it is distribution orien... By analyzing the relationship among government, market driving forces, distribution orientation of banking industry, service opportunity equality and spatial patterns, this paper proposes that it is distribution orientation that lead to the formation and evolution of spatial pattern of banking industry. The difference of the distribution orientation leads to the separation of the spatial pattern of banking industry, and the change of the distribution orientation leads to the change of spatial pattern. The degree of spatial pattern change is subject to the degree of change of distribution orientation, and the scale of bank resources in the regions, which supports the distribution orientation variation. Based on these theoretical frameworks, some indicators were designed to analyze the pattern change of China′s banking industry and its effects since 1995 under the change of the distribution orientation. This paper finds that the orientation of economic benefit maximization driven by market causes the banking industry to concentrate in economically developed regions.The government, which does not follow the orientation of economic benefit maximization, plays a role of stabilizer. Since the bank branches in the regions with the greatest change in bank branch distribution are too few, and regions with the greatest change in bank loan allocation are the regions with lots of loans, the pattern change of the banking industry in physical form is not as notable as that in economic form. 展开更多
关键词 banking industry geographic pattern change distribution orientation driving mechanism China
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Changes in cortical activation patterns accompanying somatosensory recovery in a stroke patient: a functional magnetic resonance imaging study 被引量:3
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作者 Yong Hyun Kwon Mi Young Lee 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第15期1485-1488,共4页
The somatosensory system plays a crucial role in executing precise movements by providing sensory feedback (Farrer et al., 2003; Rabin and Gordon, 2004). Somatosensory dys- function is a common problem following str... The somatosensory system plays a crucial role in executing precise movements by providing sensory feedback (Farrer et al., 2003; Rabin and Gordon, 2004). Somatosensory dys- function is a common problem following stroke. In partic- ular, somatosensory impairments, such as impairment in touch, proprioception, light touch, and vibration have been frequently observed (Carey et al., 1993; Sullivan and Hed- man, 2008; Tyson et al., 2008). Patients with somatosensory dysfunction show negative effects on motor control, and it sometimes becomes difficult to perform daily activities independently. 展开更多
关键词 SMA Changes in cortical activation patterns accompanying somatosensory recovery in a stroke patient a functional magnetic resonance imaging study
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The Evolution of Landscape Patterns of and Optimization Measures for Urban Core Areas Against the Background of Urbanization: A Case Study of Yangling Demonstration Zone
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作者 TANG Ying ZHANG Pei SHI Chengyong 《Journal of Landscape Research》 2018年第4期67-71,77,共6页
Studying tiie urban landscape pattern plays a crucial role in scientific land use and management and in improving the urban ecological environment In this paper, AutoCAD, ArcGIS, Fragstats, and other software were u... Studying tiie urban landscape pattern plays a crucial role in scientific land use and management and in improving the urban ecological environment In this paper, AutoCAD, ArcGIS, Fragstats, and other software were used to analyse the data of the fourth phase of land use in the core atea of Yangling Demonstration Zone. The results showed that: ① in the core area, the percentage of construction land incteased from 18.22% to 61.72%, and the percentage of agricultufal land decreased from 58.36% to 11.14%. And the fafm land was fragmented, and traffic connectivily was strengthened. The afea of garden land was reduced from 251.89 hm2 to 50.38 hm^2, and the landscape metric of forest land showed an inverted V-shaped curve. ②The year 2009 in four phases witnessed the greatest landscape fragmentation, both Edge Density (ED) and Ingest Patch Index (LPI) increased, and human interference enhanced the overall landscape complexity. Measures were fotmulated in terms of deaf development goals, optimized allocation of land resoutces, effective protection of ecological ted lines, and definite ecological responsibility, so as to optimize the urban landscape pattern. 展开更多
关键词 Yangling Demonstration Zone Urban core area Changes in landscape patterns Optimization measures
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Changes in the Income-Expenditure Pattern in Rural China
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《China Population Today》 1998年第Z2期17-18,20,共3页
关键词 Changes in the Income-Expenditure pattern in Rural China In
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Long-term follow-up of liver alveolar echinococcosis using echinococcosis multilocularis ultrasound classification 被引量:6
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作者 Jasmin Schuhbaur Melissa Schweizer +3 位作者 Jana Philipp Julian Schmidberger Patrycja Schlingeloff Wolfgang Kratzer 《World Journal of Gastroenterology》 SCIE CAS 2021年第40期6939-6950,共12页
BACKGROUND When Echinococcus multilocularis infects humans as a false intermediate host,alveolar echinococcosis(AE)usually manifests primarily intrahepatically and is initially asymptomatic.If the disease remains undi... BACKGROUND When Echinococcus multilocularis infects humans as a false intermediate host,alveolar echinococcosis(AE)usually manifests primarily intrahepatically and is initially asymptomatic.If the disease remains undiagnosed and untreated,progressive growth occurs,reminiscent of malignant tumours.The only curative therapy is complete resection,which is limited to localised stages,and palliative drug therapy is used otherwise.Consequently,early diagnosis and reliable detection of AE lesions are important.For this reason,abdominal ultrasonography,as the most common primary imaging for AE,relies on classification systems.AIM To investigate how hepatic AE lesion sonomorphology changes over time in the Echinococcosis Multilocularis Ulm Classification(EMUC)-ultrasound(US)classification.METHODS Based on data from Germany’s national echinococcosis database,we evaluated clinical and US imaging data for 59 patients according to the AE case definition in our preliminary retrospective longitudinal study.There had to be at least two liver sonographies≥6 mo apart,≥1 hepatic AE lesion,and complete documentation in all US examinations.The minimum interval between two separately evaluated US examinations was 4 wk.The AE reference lesion was the largest hepatic AE lesion at the time of the first US examination.To classify the sonomorphologic pattern,we used EMUC-US.In addition to classifying the findings of the original US examiner,all reference lesions at each examination time point were assigned EMUC-US patterns in a blinded fashion by two investigators experienced in US diagnosis.Statistical analysis was performed using SAS version 9.4(SAS Institute Inc.,Cary,NC,United Stated).P values<0.05 were considered statistically significant.RESULTS The preliminary study included 59 patients,38(64.5%)women and 21(35.6%)men.The mean age at initial diagnosis was 59.9±16.9 years.At the time of initial ultrasonography,a hailstorm pattern was present in 42.4%(25/59)of cases,a hemangioma-like pattern in 16.9%(10/59),a pseudocystic pattern in 15.3%(9/59),and a metastasis-like pattern in 25.4%(15/59).For the hailstorm pattern,the average lesion size was 67.4±26.3 mm.The average lesion size was 113.7±40.8 mm with the pseudocystic pattern and 83.5±27.3 mm with the hemangioma-like pattern.An average lesion size of 21.7±11.0 mm was determined for the metastasis-like pattern.Although the sonomorphologic pattern remained unchanged in 84.7%(50/59)of AE reference lesions,15.3%(9/59)showed a change over time.A change in pattern was seen exclusively for AE lesions initially classified as hemangioma-like or pseudocystic.A total of 70%(7/10)of AE lesions initially classified as hemangioma-like showed a relevant change in pattern over time,and 85.7%(6/7)of these were secondarily classified as having a hailstorm pattern,with the remainder(1/7;14.3%)classified as having a pseudocystic pattern.A total of 22.2%(2/9)of AE lesions initially classified as pseudocystic showed a relevant change in pattern over time and were classified as having a hailstorm pattern.For AE lesions initially classified as having a hailstorm or metastatic pattern,no pattern change was evident.All patients with pattern change were on continuous drug therapy with albendazole.CONCLUSION The sonomorphology of hepatic AE lesions may change over time.The hemangioma-like and pseudocystic patterns are affected. 展开更多
关键词 Alveolar echinococcosis Echinococcus multilocularis ULTRASONOGRAPHY Sonomorphology pattern change
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Use of Intensity Analysis to Measure Land Use Changes from 1932 to 2005 in Zhenlai County, Northeast China 被引量:9
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作者 YANG Yuanyuan LIU Yansui +1 位作者 XU Di ZHANG Shuwen 《Chinese Geographical Science》 SCIE CSCD 2017年第3期441-455,共15页
Analyzing spatiotemporal dynamics of land use and land cover over time is widely recognized as important to better understand and provide solutions for social, economic, and environmental problems, especially in ecolo... Analyzing spatiotemporal dynamics of land use and land cover over time is widely recognized as important to better understand and provide solutions for social, economic, and environmental problems, especially in ecologically fragile region. In this paper, a case study was taken in Zhenlai County, which is a part of farming-pastoral ecotone of Northeast China. This study seeks to use multi-temporal satellite images and other data from various sources to analyze spatiotemporal changes from 1932 to 2005, and applied a quantitative methodology named intensity analysis in the time scale of decades at three levels: time interval, category, and transition. The findings of the case study are as follows: 1) the interval level of intensity analysis revealed that the annual rate of overall change was relatively fast in 1932–1954 and 1954–1976 time intervals. 2) The category level showed that arable land experienced less intensively gains and losses if the overall change was to have been distributed uniformly across the landscape while the gains and losses of forest land, grassland, water, settlement, wetland and other unused land were not consistent and stationary across the four time intervals. 3) The transition level illustrated that arable land expanded at the expense of grassland before 2000 while it gained intensively from wetland from 2000 to 2005. Settlement targets arable land and avoids grassland, water, wetland and other unused land. Besides, the loss of grassland was intensively targeted by arable land, forest land and wetland in the study period while the loss of wetland was targeted by water except for the time interval of 1976–2000. 4) During the early reclamation period, land use change of the study area was mainly affected by the policy, institutional and political factors, followed by the natural disasters. 展开更多
关键词 intensity analysis land use and land cover change pattern driving forces Northeast China
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Phase change microcapsules in thermal Energy applications:A critical review 被引量:1
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作者 XIAO Anna YUAN Qingchun 《储能科学与技术》 CAS CSCD 2017年第4期607-622,共16页
Phase change microcapsules can carry large amounts of heat and be dispersed into other mediums either as a solid composite or as slurry fluids without changes to their appearance or fluidity. These two standout featur... Phase change microcapsules can carry large amounts of heat and be dispersed into other mediums either as a solid composite or as slurry fluids without changes to their appearance or fluidity. These two standout features make phase change microcapsules ideal for use in thermal energy applications to enhance the efficiency of energy utilisation. This review paper includes methods used for the encapsulation of phase change materials, especially the method suitable for large scale productions, the trends of phase change microcapsule development and their use in thermal energy applications in static and dynamic conditions. The effect of phase change microcapsules on convective heat transfer through addition to thermal fluids as slurries is critically reviewed. The review highlighted that so far the phase change microcapsules used mainly have polymeric shells, which has very low thermal conductivities. Their enhancement in convective heat transfer was demonstrated in locations where the phase change material experiences phase change. The phase change results in the slurries having higher apparent local specific heat capacities and thus higher local heat transfer coefficients. Out of the phase change region, no enhancement is observed from the solid microcapsule particles due to the low specific heat capacity and thermal conductivity of the phase change microcapsules compared to that of water, which is normally used as slurry media in the test. To further the research in this area, phase change microcapsules with higher specific heat capacity, higher thermal conductivity and better shape stability need to be applied. 展开更多
关键词 phase change microcapsule complex microencapsulation SLURRY phase change patterns convective heat transfer enhancement
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Precipitation changes in the mid-latitudes of the Chinese mainland during 1960–2014 被引量:5
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作者 HU Yuling WANG Shigong +1 位作者 SONG Xuping WANG Jiaxin 《Journal of Arid Land》 SCIE CSCD 2017年第6期924-937,共14页
Based on daily precipitation data from 163 meteorological stations, this study investigated precipitation changes in the mid-latitudes of the Chinese mainland(MCM) during 1960–2014 using the climatic trend coeffici... Based on daily precipitation data from 163 meteorological stations, this study investigated precipitation changes in the mid-latitudes of the Chinese mainland(MCM) during 1960–2014 using the climatic trend coefficient, least-squared regression analysis, and a non-parametric Mann-Kendall test.According to the effects of the East Asian summer monsoon on the MCM and the climatic trend coefficient of annual precipitation during 1960–2014, we divided the MCM into the western MCM and eastern MCM. The western MCM was further divided into the western MCM1 and western MCM2 in terms of the effects of the East Asian summer monsoon. The main results were as follows:(1) During the last four decades of the 20^(th) century, the area-averaged annual precipitation presented a significant increasing trend in the western MCM, but there was a slight decreasing trend in the eastern MCM, where a seesaw pattern was apparent. However, in the 21^(st) century, the area-averaged annual precipitation displayed a significant increasing trend in both the western and eastern MCM.(2) The trend in area-averaged seasonal precipitation during 1960–2014 in the western MCM was consistent with that in the eastern MCM in winter and spring. However, the trend in area-averaged summer precipitation during1960–2014 displayed a seesaw pattern between the western and eastern MCM.(3) On an annual basis,both the trend in rainstorms and heavy rain displayed a seesaw pattern between the western and eastern MCM.(4) The precipitation intensity in rainstorms, heavy rain, and moderate rain made a greater contribution to changes in the total precipitation than precipitation frequency. The results of this study will improve our understanding of the trends and differences in precipitation changes in different areas of the MCM. This is not only useful for the management and mitigation of flood disasters, but is also beneficial to the protection of water resources across the MCM. 展开更多
关键词 precipitation changes the mid-latitudes of the Chinese mainland seesaw pattern rainy days precipitation intensity precipitation frequency
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Increasing Wages,Factor Substitution,and Cropping Pattern Changes in China 被引量:1
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作者 Zhoufu Yan Shurui Zhang +1 位作者 Fangwei Wu Binlei Gong 《China & World Economy》 2023年第5期190-214,共25页
This article analyzed the influence of increasing wages on cropping patterns from theoretical and empirical perspectives.The results showed that the increasing labor cost provided a significant incentive to adjust the... This article analyzed the influence of increasing wages on cropping patterns from theoretical and empirical perspectives.The results showed that the increasing labor cost provided a significant incentive to adjust the grain cropping pattern,which increased the production of the three major cereal grains but reduced the production of other grain crops.Increasing wages had a significant negative impact on cash crops.More laborintensive cash crops experienced a larger negative impact in the context of increasing wages.The increase in labor costs also had a negative impact on the proportion of vegetables produced,which was more evident in northern China.A further mechanism test indicated that factor substitution was a significant reason for cropping pattern changes;this illustrated the substitution of labor by machinery not only between grain crops and cash crops but also among different cash crops. 展开更多
关键词 cropping pattern changes factor substitution increasing wages production transformation
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Reading Patterns Changing
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作者 YU LINTAO 《Beijing Review》 2011年第21期40-41,共2页
Modern life is changing the way people read April 23 was the 16th World Book and Copyright Day,also known as the World Book Day.Reading-related problems have once again attracted people’s attention.Today,living a lif... Modern life is changing the way people read April 23 was the 16th World Book and Copyright Day,also known as the World Book Day.Reading-related problems have once again attracted people’s attention.Today,living a life with an increasingly rapid pace,most people 展开更多
关键词 Reading patterns changing World CPC
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Vertical structure and dominating factors of sand body during Late Triassic Chang 9 time of Yanchang Formation in Ordos Basin, NW China
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作者 丁熊 陈景山 +5 位作者 谭秀成 林丹 赵子豪 姚泾利 邓秀芹 李元昊 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1405-1418,共14页
Based on a synthetic geological study of drilling, well logging and core observations, two main genetic types of Chang 9sand body in Odors Basin were recognized, which included two effects, that is, delta environment ... Based on a synthetic geological study of drilling, well logging and core observations, two main genetic types of Chang 9sand body in Odors Basin were recognized, which included two effects, that is, delta environment and tractive current effects that lead to the development of mouth bar, distal bar, sheet sand and other sand bodies of subaerial and subaqueous distributary channel,natural levee, flood fan and delta front, and shore-shallow lake environment and lake flow transformation effects that result in the development of sandy beach bar, sheet sand and other sand bodies. Chang 9 sand body mainly developed five basic vertical structures, namely box shape, campaniform, infundibuliform, finger and dentoid. The vertical stacking patterns of multilayer sand body was complex, and the common shapes included box shape + box shape, campaniform + campaniform, campaniform + box shape, infundibuliform + infundibuliform, campaniform + infundibuliform, box shape + campaniform, box shape + infundibuliform,and finger + finger. Based on the analysis on major dominating factors of vertical structure of sand body, sedimentary environment,sedimentary facies and rise, fall and cycle of base level are identified as the major geological factors that control the vertical structure of single sand body as well as vertical stacking patterns and distribution of multistory sand bodies. 展开更多
关键词 vertical structure stacking pattern sand body Chang 9 time Ordos Basin
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Population evolution at the prefecture-level city scale in China:Change patterns and spatial correlations 被引量:4
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作者 XIAN Yue CHEN Mingxing 《Journal of Geographical Sciences》 SCIE CSCD 2022年第7期1281-1296,共16页
China has entered a new stage of high-quality urbanization.Therefore,it is critical to grasp the latest population distribution and dynamics.Using mean-variance grading,Moran’s index,and the Theil index,this study co... China has entered a new stage of high-quality urbanization.Therefore,it is critical to grasp the latest population distribution and dynamics.Using mean-variance grading,Moran’s index,and the Theil index,this study compared the differences in population changes between 2010–2020 and 2000–2010 at the prefecture-level city scale based on census data to analyze the new trends in population evolution.We found that:(1)New growth poles of the population are inland provincial capitals,forming rapid-growing zones together with coastal urban agglomerations.Population growth in over 60%of the cities in the northern coastal urban agglomeration has slowed.(2)The scope of population loss in inland areas is constantly expanding.In the northeastern part of China,92.7%of the cities have lost population,making this a typical population loss area.(3)Population shrinkage in the northeastern region and growth in the Pearl River Delta urban agglomeration show diffusion characteristics,while population patterns around the provincial capital are in a polarized stage.(4)The Theil index of population distribution increased,with 83.91%of differences coming from between groups,indicating that the gap between cities of different sizes has further expanded.This study provides scientific support for the coordinated promotion of nearby and remote urbanization. 展开更多
关键词 population distribution agglomeration and decentralization pattern change nearby urbanization prefecture-level city
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Spatial Dynamics of Cropland and Cropping Pattern Change Analysis Using Landsat TM and IRS P6 LISS III Satellite Images with GIS 被引量:3
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作者 Md.Rejaur Rahman S.K.Saha 《Geo-Spatial Information Science》 2009年第2期123-134,共12页
The study of the spatial patterns and temporal changes of cropland is important to understand the underlying factors and the functional effects of the agricultural landscape. On the other hand, crop dynamics mapping i... The study of the spatial patterns and temporal changes of cropland is important to understand the underlying factors and the functional effects of the agricultural landscape. On the other hand, crop dynamics mapping is essential to know the overall agro-spatial diversity of the area. Therefore, this paper addressed a spatio-temporal analysis of cropland and cropping pattern change in the Bogra district of Bangladesh over the last 16 years (between 1988/89 and 2004/05). In this paper, crop mapping from multi-temporal and multi-sensor satellite images was described. Landsat TM and IRS P6 LlSS Ⅲ satellite images were used with GIS for spatial dynamics of cropland and cropping pattern change analysis. First, seasonal cropland maps were derived from object-based classification of satellite images, then two-date classified image differencing with GIS overlay technique and decision rules were applied. Cropping pattern change was analyzed in a spatial and quantitative way for the 16 years and for this, Integrated Land and Water Information System (ILWIS) and Land Change Modular (LCM) of IDRISl Andes were used. The results showed that in the area, mono crop cultivation was found in summer, but in winter, areas under different crop cultivation had changed dramatically. Change analysis showed that the changes mainly occurred in the north northwest and southwest of the areas, and during the time the highest change area was found under the rice-potato pattern. 展开更多
关键词 cropland dynamics gain and loss of cropland spatial trend cropping pattern change Landsat TM and IRS P6 LISS GIS
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Changes in Family Income Patterns in LargeChinese Cities Since the Reform 被引量:1
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作者 沈崇麟 杨善华 《Social Sciences in China》 1998年第1期38-48,192-144,共13页
关键词 Changes in Family Income patterns in LargeChinese Cities Since the Reform
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