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Evolution stage,spatial and temporal variabilities of granite landforms in the Mount Wugongshan in Jiangxi Province of South China
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作者 CHAI Le ZHONG Cun-di +4 位作者 GUO Fu-sheng HUANG Xin-shu WANG Dao-ying SHAO Chong-jian CHEN Liu-qin 《Journal of Mountain Science》 SCIE CSCD 2022年第10期2743-2757,共15页
Granites of the Mesozoic Era are widespread in South China,and many of them have been shaped into spectacular landscapes with high tourism development values.However,the controlling factors and evolution stages of the... Granites of the Mesozoic Era are widespread in South China,and many of them have been shaped into spectacular landscapes with high tourism development values.However,the controlling factors and evolution stages of these granite landscapes were poorly understood.In this study,the Hypsometric Integral curves(HIc),and Hypsometric Integral(HI)values of the Mount Wugong were extracted from digital elevation model data in a geographic information system environment.The relationships between the HIc,HI values,and factors including the tectonism,lithology and climate of the study area were analyzed to determine the evolution of granite landscapes evolution in the main scenic areas of the Mount Wugongshan.The HI values on the northwestern and southeastern slopes of the Mount Wugongshan range from 0.223 to 0.415 and 0.385 to 0.465,respectively;the HIc are mainly concave on the northwestern slopes and irregularly‘Sshaped’on the southeastern slopes.The main ridge of the granite geomorphic scenic area of the Mount Wugongshan,where the alpine meadow geomorphic landscape is located,is in the youthful stage of geomorphic evolution,the Mt.Jinding-Mt.Wanlong and Mt.Mingyue-Wentang scenic areas are in the old stage,and the Yangshimu scenic area is in the mature stage.Differences in watershed scale may be the main reason for the variabilities in geomorphic evolution in the area,while the regular development of tectonic phenomena is a key factor shaping the spatial variability in the watersheds on both sides of the main ridge. 展开更多
关键词 Mount Wugongshan Granite landforms Landscape formation stage Hypsometric Integral
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Aesthetic evaluation of yardang landforms landscape:the Dunhuang Yardang National Geo-park example
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作者 RuiJie Dong ZhiBao Dong 《Research in Cold and Arid Regions》 CSCD 2015年第3期265-271,共7页
Dunhuang Yardang National Geo-park, situated in the Gansu Province of northwestern China (40°25′36″N-40°33′10″N, 93°00′00″E-93°13′30″E), was chosen as a research locality of aesthetics ev... Dunhuang Yardang National Geo-park, situated in the Gansu Province of northwestern China (40°25′36″N-40°33′10″N, 93°00′00″E-93°13′30″E), was chosen as a research locality of aesthetics evaluation of yardang landforms landscape. The yardang landforms landscape is a composite structural system of patch-corridor-matrix, with four landscape unit elements as dense group, sparse group, single body and remnant. The study of the landscape aesthetics spatial pattern of Dunhuang Yardang National Geo-park shows that yardang dense group, sparse group and single body provide the greatest contribution to the aesthetic value of yardang landforms landscape. Yardang bodies are scarce, unique, irreplaceable, and priceless resources in yardang landforms areas. However, they are easily destroyed under the influence of the natural and artificial factors. Therefore, when the tourism potential of yardang landforms landscape is exploited, the protection should be fully improved. 展开更多
关键词 aesthetic evaluation yardang landforms landscape elements spatial structure Dunhuang
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A study on neogene volcanic landforms of the middle Tanlu fault belt
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作者 HAN Mei (Geography Department, Shandong Normal University, Jinan 250014,China) 《Journal of Geographical Sciences》 SCIE CSCD 2000年第4期121-128,共8页
The west block of the middle belt of TanLu fault belt is one of the areas where volcanic landforms are mainly distributed. This paper divides the volcanic landforms into four grades according to formation, morphology,... The west block of the middle belt of TanLu fault belt is one of the areas where volcanic landforms are mainly distributed. This paper divides the volcanic landforms into four grades according to formation, morphology, and ingredient of matter. Lava cones are divided into two types based on the force of top-support and the fluid form of magma: the arc-projecting type and spring-spilling type. Furthermore, the courses of development of volcanic landforms are divided into three stages according to the form and strength of volcanic activities. 展开更多
关键词 volcanic landforms NEOGENE TanLu fault belt
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Danxia Landforms: Rosy Clouds on Earth
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《China Today》 2019年第8期70-73,共4页
A Danxia landform is a red-bed landform characterized by steep cliffs. It was initially discovered and named by Chinese scholars. Although there are red-bed landforms in many parts of the world, China, with a special ... A Danxia landform is a red-bed landform characterized by steep cliffs. It was initially discovered and named by Chinese scholars. Although there are red-bed landforms in many parts of the world, China, with a special fondness for the color red, boasts the most widely distributed Danxia possessing unique characteristics. This is a mesmerizing natural formation and a special gift that nature has bestowed upon this country. 展开更多
关键词 DANXIA landforms Rosy CLOUDS a red-bed LANDFORM
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Relationship between the characteristics of landforms and sediments as well as the plume front in the Hangzhou Bay
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作者 Feng Yingjun Li Yan and Li Bogen Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1993年第1期133-144,共12页
Sedimentary environments in the Hangzhou Bay are introduced by a three-subregional landform pattern and a sedimentation map with six major sedimentation types. The geographic setting, sediment transportation and sedim... Sedimentary environments in the Hangzhou Bay are introduced by a three-subregional landform pattern and a sedimentation map with six major sedimentation types. The geographic setting, sediment transportation and sedimentation in different subregions are discussed with sediment grain parameters. Sedimentary basin suffering from effect of plume front can be identified by the fine sediments with median ( Mdφ ) 7φ-8φ, clay content 30% - 40% and silt 60% - 70%. Sediment transportation along the plume front seems not to be a direct effect on sedimentary formation of the shoals fringing the south coast of the Hangzhou Bay. 展开更多
关键词 Relationship between the characteristics of landforms and sediments as well as the plume front in the Hangzhou Bay well
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Landforms Evolution of Wadi Qudaid Area, West Central Arabian Shield, Saudi Arabia: An Example of the Role of the Geological Factors in the Urban Extensions
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作者 Ali A. Mesaed Mohammed A. M. Alghamdi Abdullah R. Sonbul 《Open Journal of Geology》 2020年第6期612-640,共29页
Wadi Qudaid is located in the west central part of Saudi Arabia. It about 135</span><span style="font-size:10pt;font-family:""> </span><span style="font-size:10pt;font-family:&... Wadi Qudaid is located in the west central part of Saudi Arabia. It about 135</span><span style="font-size:10pt;font-family:""> </span><span style="font-size:10pt;font-family:""><span style="font-family:Verdana;font-size:12px;">km to the northeast of Jeddah city along Al Haramein highway and it represents the upstream of the very large alluvial plain along the Red Sea coast. It runs in NE direction parallel to many wadis of the west central part of Saudi Arabia </span><i><span style="font-family:Verdana;font-size:12px;">i.e.</span></i><span style="font-family:Verdana;font-size:12px;"> Wadi Fatima, wadi Sitarah. The wadi floor is filled by Quaternary deposits which represent good groundwater aquifer. Geologically, the present-day residual landforms of Wadi Qudaid are composed mainly of Precambrian Arabia shield rocks overlained by Tertiary sedimentary rocks and finally harrat (Tertiary volcanic). The Precambrian rocks are represented by 1) a lower layered basic and intermediate volcanic and the intercalated volcaniclastics. This unit is correlatable with Samran Group, 2) an upper layered acidic volcanic and the intercalated acidic volcaniclastics. The Arabian shield rocks are intensively folded and dragged along the major NE faults. They are directly overlain by Tertiary basic volcanic (harrat) and the related volcanoclastic red beds). The main geomorphologic elements of the </span><span style="font-family:Verdana;font-size:12px;">study area include plateau, scarps, and the wadi floor. The plateau is represented </span><span style="font-family:Verdana;font-size:12px;">by the black basaltic sheet that contains some semi-rounded depressions filled with Quaternary eolian sands. The scarps of the main wadi and its tributaries are nearly steep and contain many asphaltic roads with some isolated cone hills detached from the scarps. Geomorphological, Wadi Qudaid</span><span style="font-family:Verdana;font-size:12px;"> represents the incomplete erosion cycle that begins with the formation of deep galleries and very steep and narrow wadies formed along the major NE faults and related fractures and folds. The progress of the erosion processes led to the formation of narrow interfluves as a result of pedimentation and sculpturing of the wadies sides by scarp retreat. The peniplanation stages of the erosion cycles are reached in the southwestern and the central part of the wadi where fast peniplained areas were formed. The results of this study revealed the role of the different geological processes (lithology, structural elements and climatic conditions) in the distribution of present-day human populations in urban extensions. Qudaid, Dhubaya-Jumah, Dabyah, Al Khamrah, Almansa and Al</span></span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">Massamah are the main villages of Wadi Qudaid area. 展开更多
关键词 Wadi Qudaid Geomorphology of Saudi Arabia landforms Evolution Erosion Cycle Urban Extensions
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Automatic recognition of loess landforms using Random Forest method 被引量:14
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作者 ZHAO Wu-fan XIONG Li-yang +1 位作者 DING Hu TANG Guo-an 《Journal of Mountain Science》 SCIE CSCD 2017年第5期885-897,共13页
The automatic recognition of landforms is regarded as one of the most important procedures to classify landforms and deepen the understanding on the morphology of the earth. However, landform types are rather complex ... The automatic recognition of landforms is regarded as one of the most important procedures to classify landforms and deepen the understanding on the morphology of the earth. However, landform types are rather complex and gradual changes often occur in these landforms, thus increasing the difficulty in automatically recognizing and classifying landforms. In this study, small-scale watersheds, which are regarded as natural geomorphological elements, were extracted and selected as basic analysis and recognition units based on the data of SRTM DEM. In addition, datasets integrated with terrain derivatives(e.g., average slope gradient, and elevation range) and texture derivatives(e.g., slope gradient contrast and elevation variance) were constructed to quantify the topographical characteristics of watersheds. Finally, Random Forest(RF) method was employed to automatically select features and classify landforms based on their topographical characteristics. The proposed method was applied and validated in seven case areas in the Northern Shaanxi Loess Plateau for its complex andgradual changed landforms. Experimental results show that the highest recognition accuracy based on the selected derivations is 92.06%. During the recognition procedure, the contributions of terrain derivations were higher than that of texture derivations within selected derivative datasets. Loess terrace and loess mid-mountain obtained the highest accuracy among the seven typical loess landforms. However, the recognition precision of loess hill, loess hill–ridge, and loess sloping ridge is relatively low. The experiment also shows that watershed-based strategy could achieve better results than object-based strategy, and the method of RF could effectively extract and recognize the feature of landforms. 展开更多
关键词 Landform recognition Random Forest Feature fusion DEM Loess landform
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Developmetn stage threshold of watershed Landforms in Loess Plateau and separation of erosion mechanism 被引量:2
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作者 LU Zhong-chen1, CHEN Shao-feng2,YUAN Bao-yin3,CHEN Hao4 (1.Eco-Environment Research Center,CAS,Beijing 100085,China 2.Institute of Policy andManagement Science,CAS,Beijing 100080,China +1 位作者 3.Institute of Geology,CAS,Beijing1000029,China 4.Institute of Geograp 《Journal of Geographical Sciences》 SCIE CSCD 2002年第1期81-90,共10页
Threshold is a limit and marginal point when a qualitative change takes place. Since threshold principle was firstly used in landform research by S.A.Schumm in the 1970s, the quantitative research on watershed landfor... Threshold is a limit and marginal point when a qualitative change takes place. Since threshold principle was firstly used in landform research by S.A.Schumm in the 1970s, the quantitative research on watershed landform development stage has come true. Davis proposed a three-stage model on landform evolution: young, mature and old stages. Thereafter Strahler quantified this model by hypsometric analysis method. The authors thought that the material movement stage cannot be expressed by hypsometric method in watershed landform at development stage, because of the uncertainty on stage delimitation. To meet this shortcoming, this paper presents an integral erosion value method. A clear delimitation on landform development stage in the Loess Plateau region has been tested by this method. The result shows that gullied loessial hilly area is at the mature stage, and gullied loessial tableland area is at the young stage. It is estimated that from the point of erosion related sediment yield, natural erosion accounts for 70% of the total erosion amount, and artificial accelerating erosion is 30%. Therefore soil and water conservation is very crucial for the Loess Plateau. 展开更多
关键词 landform development stage hypsometric analysis method integral erosion value natural erosion artificial accelerating erosion
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Comparative studies of Danxia landforms in China 被引量:1
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作者 QI Deli YU Rong +2 位作者 ZHANG Renshun GE Yunjian LI Jialin 《Journal of Geographical Sciences》 SCIE CSCD 2005年第3期337-345,共9页
Danxia geomorphology originates fi'om China. This paper studies the spatial distribution and differences in characteristics of Danxia landforms. Based on relevant research and investigations, three congregated areas ... Danxia geomorphology originates fi'om China. This paper studies the spatial distribution and differences in characteristics of Danxia landforms. Based on relevant research and investigations, three congregated areas of Danxia landform in China are discussed in this paper. They are the southeast area (including Jiangxi, Fujian, Zhejiang, Hunan and Guangxi provinces), the southwest area (the transitional zone of Yunnan-Guizhou Plateau and Sichuan Basin) and the northwest area (including Longshan mountain and along the banks of the Huanghe River and its anabranches). Not only the conditions of geology and geography of the three areas but also the differences of Danxia landforms of the three areas are analyzed. The Danxia landscape, characterized by upright-shaped peaks, Danxia mesa, stone wall, cave and vertical cave, "Danxia natural bridge", "a narrow strip of sky" and so on, often presents in the southeast area. The landscape of southwest area is characterized by Danxia escarpment faces and waterfalls. In the northwest area, the Danxia landscape has the traits of arid areas simultaneously, for example, mud-coating type, columniation type, board type, moreover, it is greatly different between these environmental factors such as the microclimate, water, wind, and the loess cover. Finally it explores the causes which lead differences in landform and also explains the landform formation process and its mechanism with reference to the rates of crustal uplift, the tectonic red-basin, and the external processes including working of running water, weathering, biogenic, gravity in each area of Danxia Landforms in China. 展开更多
关键词 Danxia landform LANDSCAPE China
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A PRELIMINARY STUDY ON QUATERNARY GLACIAL LANDFORMS IN MT.MA'AN
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作者 罗成德 《Chinese Geographical Science》 SCIE CSCD 1998年第1期92-96,共5页
APRELIMINARYSTUDYONQUATERNARYGLACIALLANDFORMSINMT.MA’ANLuoChengde(罗成德)DepartmentofGeography,LeshanTeachersCo... APRELIMINARYSTUDYONQUATERNARYGLACIALLANDFORMSINMT.MA’ANLuoChengde(罗成德)DepartmentofGeography,LeshanTeachersColege,Leshan614004... 展开更多
关键词 southwest edge of Sichuan Basin Mt.Ma’ an GLACIAL LANDFORM QUATERNARY glacier
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Analysis of Characteristics of a Heavy Rainstorm Process in Nanchang City on July 7,2020
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作者 Fengling ZENG Landi ZHONG Minghua MENG 《Meteorological and Environmental Research》 2024年第1期1-7,11,共8页
Based on the conventional observation data,dual polarization radar data and NCEP reanalysis data,the large-scale circulation background field,mesoscale conditions and formation causes of a heavy rainstorm in Nanchang ... Based on the conventional observation data,dual polarization radar data and NCEP reanalysis data,the large-scale circulation background field,mesoscale conditions and formation causes of a heavy rainstorm in Nanchang on July 7,2020 were studied.It was found that this heavy rainstorm occurred under the weather background of the confrontation between the northward air flow behind the trough and the strong southwest warm and humid air flow to the northwest of the subtropical high.The divergence at the upper level,the shear in the middle and low levels,the southward movement of cold air at the low level,unusually abundant water vapor and high unstable energy caused the heavy rainstorm weather.In this process,under the influence of continuous eastward movement of several strong echo cells,an obvious"train effect"was formed in Nanchang,so that the local rainfall was continuous and intense.Moreover,the average of VIL was about 17 kg/m 2,and its variation characteristics were consistent with the variation trend of 5-min rainfall intensity,which had a certain indicator effect on short-term heavy precipitation.The topography of the Meiling Mountain in the west of Nanchang had a great influence on the formation and precipitation distribution of the heavy rain process.There was a strong rainstorm center near the mountain,and the precipitation was obviously larger than that in the plain area. 展开更多
关键词 Short-term heavy precipitation Mesoscale system Train effect Meiling landform
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Combined gully profiles for expressing surface morphology and evolution of gully landforms 被引量:3
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作者 Jingwei LI Liyang XIONG Guo’an TANG 《Frontiers of Earth Science》 SCIE CAS CSCD 2019年第3期551-562,共12页
The expression of gully landforms can be regarded as an indicator of the evolutionary process of gullies. Most existing studies on the expression of gully landforms focus on plane characteristics. However, the vertica... The expression of gully landforms can be regarded as an indicator of the evolutionary process of gullies. Most existing studies on the expression of gully landforms focus on plane characteristics. However, the vertical characteristics of a gully should be given considerable attention because gullies have mainly eroded the surface in the vertical direction. Current studies on vertical characteristics of gullies mainly focused on a single gully or rarely a few gullies, thereby failing to express the entire gully landform in a certain area. In this study, gully profile combination (GPC) was proposed to investigate the morphology and reveal the evolution of gully landforms. It was defined as the combination of vertical projection of all gully profiles in the entire drainage basin. Then, a gully evolution index and its statistic values were used to reveal the evolution of gully landforms based on GPC. The proposed method was applied and validated in three typical loess gully landform areas (i.e., loess tableland, ridge, and hill) in the Loess Plateau of China. Results show that GPC can effectively express gully landforms. The specific geomorphological feature (monoclinic loess tableland) can also be identified using GPC. The gully evolution index results also demonstrate different magnitudes of gully evolutionary stages in a certain area, which reflect the diversity of gullies. The average and median values of the gully evolution index increase in the three typical loess gully landforms. From loess tableland, loess ridge, and loess hill, the average values are 0.653, 0.703, and 0.763, and the median values are 0.661, 0.719, and 0.783, respectively. This method is also found to be stable with gully extraction thresholds for distinguishing different loess gully land-forms. Accordingly, the evolution magnitudes of loess gully are obtained. 展开更多
关键词 GULLY profile combination GULLY EVOLUTION GULLY morphology LOESS LANDFORM
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The recent evolution of dune landforms and its environmental indications in the mid-latitude desert area(Hexi Corridor)
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作者 ZHU Bingqi 《Journal of Geographical Sciences》 SCIE CSCD 2022年第4期617-644,共28页
The history of dune landform changes and dust activity at mid-latitudes is a good archive for exploring environmental changes and related landscape response.In this study,the dynamic changes,material sources,dust acti... The history of dune landform changes and dust activity at mid-latitudes is a good archive for exploring environmental changes and related landscape response.In this study,the dynamic changes,material sources,dust activity history and the influencing factors of typical sand dunes in the Hexi Corridor were comprehensively analyzed from the aspects of aeolian geomorphology,grain-size sedimentology,geochemistry and climatology.The results show that in the past half century,the typical crescent-shaped dunes and chains of crescent-shaped dunes in the study area have moved or swayed greatly,with an average speed ranging from 0.8 m/a(Dunhuang)to 6.2 m/a(Minqin).The dynamic changes of sand dunes are mainly affected by annual precipitation,annual average wind speed and annual gale days,which indicates that climate is the primary influencing factor of dune landform changes.The three-stage grain-size curve model of dune sands is obviously different from that of gobi sediments(two-stage),revealing the“immaturity”of the latter in sedimentology,while the former has experienced efficiently aeolian differentiation and non-local origin.The comprehensive evidences of paleogeography,sedimentology and geochemistry reveal that the source materials of sand dunes are mainly alluvial/proluvial and palaeo-fluvial sediments,including clastic sediments in the denudation/erosion zones of the north and south piedmonts.Indicators such as the proportion of surface fine particles,the coverage of surface salt crusts,and the content of erodible sandy materials indicate that the western gobi areas are not the main source areas of wind-blown dust in the central and eastern parts of the Hexi Corridor.The spatial distribution of the movement direction of sand dunes is similar to that of the regional dominant wind direction,which indicates that the difference in the dynamic evolution of dune landforms between the east and west of the Hexi Corridor should be controlled by the regional-scale wind system,that is,controlled by the dynamic mechanism rather than the difference in material sources.The warming and humidification of the Hexi climate is a synchronous response to the global warming and the strengthening of the Asian Summer Monsoon.It is also the main reason for the reduction of dust storms in the study area,which means that a potential inverse desertification process exists in the Hexi Corridor during the same period and it is also controlled by climate change.However,the process of desertification in the oasis areas during the period is caused by groundwater fluctuation affected by human activities. 展开更多
关键词 dune landform Gobi landform grain size sedimentology elemental geochemistry global warming DESERTIFICATION mid-latitude deserts
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3D topological relationships of landforms and their spatial schema-based representation
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作者 Marc-O.LÖWNER 《Geo-Spatial Information Science》 SCIE EI 2013年第4期238-246,共9页
The science of geomorphology works on natural 3D landforms.Research includes the change of landforms as well as the processes causing these changes.Material transport processes lead to a composition of a geomorphic sy... The science of geomorphology works on natural 3D landforms.Research includes the change of landforms as well as the processes causing these changes.Material transport processes lead to a composition of a geomorphic system that follows a certain spatial hierarchy.The analysis of 3D topological relations of landforms can help to investigate geomorphic systems in two ways.First,chronological order of geomorphic genesis can be derived and,second,indications of material source can be found.However,at least some 3D geometric information is needed if topology is supposed to be derived and examined.Landforms cannot simply be reconstructed by surface measurements.Data capture is a major problem when buried features are under investigation.Subsurface information is gathered by drillings or geophysical methods that reveal point or line information.Unfortunately,the ISO 19107 Spatial Schema does not offer a valid representation of 3D geometry from sparse data,either by aggregating a surface and one or few points or by aggregating a surface and a line.Here,we discuss the possibilities for the analysis of chronological order of landform genesis and material dependencies that arise from applying 3D topological relationships to geomorphic system analysis.We show five relationships that are able to be observed in nature.Further,we introduce a new class for the representation of 3D objects with under-specified geometry.A_UG_Solid mediates between the Spatial Schema’s geometric primitives with a dimension less than three on the one side and a GM_Solid on the other side.Constraints to aggregate such a_UG_Solid are defined.The introduction of a_UG_Solid facilitates the application of 3D topological concepts to geometric objects that are known to be volumetric but have to be modeled from sparse data. 展开更多
关键词 3D Topology GEOMORPHOLOGY LANDFORM ISO 19107 spatial schema under-specified geometries
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Linking landforms and land use to land degradation in the Middle River Njoro Watershed
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作者 Zackary G.Mainuri James O.Owino 《International Soil and Water Conservation Research》 SCIE 2014年第2期1-10,共10页
Land degradation is the decline in the productive capacity of an ecosystem.This mainly occurs due to processes induced by human activities,such as deforestation,poor farming practices,or enhanced industrial growth lea... Land degradation is the decline in the productive capacity of an ecosystem.This mainly occurs due to processes induced by human activities,such as deforestation,poor farming practices,or enhanced industrial growth leading to various land degradation processes such as,flooding,drought and accelerated erosion.The objective of the study was to link landforms and land uses to land degradation.Soils in the catchments were distinguished on the basis of Physiographic,parent material/geology and soil characteristics.Eight soil mapping units were identified in the area.The validity of the identified soil mapping units were checked in the field using auger hole,mini pits,road and erosion cut observations.Representative profile pits were sighted in the major mapping units.The profile pits were described according to FAO(1977)and Kenya Soil Survey(1987).Soil classification was done according to FAO/UNESCO(1997).Soil mapping units were found to follow soil physiographic units/land forms.Soils on mountains and hills were found to be somewhat excessively drained,shallow to moderately deep.Those from uplands and plateaus were well drained,deep to very deep.Soils on plains fell on two extremes;those that were well drained,deep to very deep and those that were imperfectly drained to poorly drained,moderately deep to very deep.Physical,chemical and biological land degradation was found to take place in the different physiographic units/land forms at varying degrees.Soil erosion,nutrient depletion and vegetation depletion were found to be the most important degradation processes.Soil,physiographic units,soil susceptibility and hazard maps were drawn and their classes in the different landforms established. 展开更多
关键词 Land use LANDFORM Land degradation
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Effect of tectonic-climatic controllers on the transition of Endorheic to Exorheic Basins in the Zagros mountain range
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作者 Gholam HASSAN JAFARI Peyman MOHAMMADI-AHMADMAHMOUDI Mohsen EHTESHAMI-MOINABADI 《Journal of Mountain Science》 SCIE CSCD 2023年第12期3500-3524,共25页
Endorheic basins(ENBs) are inland drainage basins allowing no outflow to oceans.These basins in the active mountain chains of the convergence zones are under the influence of compressional tectonic activity and climat... Endorheic basins(ENBs) are inland drainage basins allowing no outflow to oceans.These basins in the active mountain chains of the convergence zones are under the influence of compressional tectonic activity and climate condition.The Zagros Mountains of Iran is one of the youngest convergence zones in which continental-continental collision has occurred.In this paper we hypothesize the formation of ENBs among the Zagros range after the epeirogenic stage in the Late Paleogene-Early Neogene.Due to tectonic activity and Quaternary climatic conditions,the ENBs pass the transition stage to exorheic,and still,some tectonic depressions are not linked to the evolutionary process of exorheic drainage of Zagros.The geometry of the drainage network of Kul and Mond basins in Fars arch shows that 67% of their water gaps are located along the thrusts and transverse basement faults in the east and west of the Fars arch.Geometrically,the Kul and Mond basins form triangles with their sides matching with the edges of the Arabian Plate where the major inherited faults of Arabian plate controls the shape of the Zagros basin and a low strain zone along the Razak fault with lower salt tectonic activity,where the wind gaps are created.The ENBs are located in the rainshadow slopes,but the Kul and Mond basins are located in the upwind slopes of rain waves.This factor and the heavy rains of the basin lead to increase of the erosion potential,destruction of depressions,and floods and consequently,the funnel-shaped gaps have a significant impact on the flood flow. 展开更多
关键词 Transition of landforms Controllers of lakes Basement faults Sedimentary basins ZAGROS
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Relative active tectonic in the metamorphic rocks of the Yaounde group: insights from geomorphic indices and topographic analysis
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作者 Jacques Bertrand ONANA Bernard NJOM +3 位作者 Franois Mvondo OWONO Mero YANNAH Thierry Abou'ou ANGO Joseph Mvondo ONDOA 《Journal of Mountain Science》 SCIE CSCD 2023年第10期2946-2974,共29页
The Yaounde Group(YG),representing the southern edge of the North Equatorial PanAfrican Belt,consists of quartzites,schists,micaschists,amphibolites,gneisses and migmatites.Tectonism has formed a landscape characteriz... The Yaounde Group(YG),representing the southern edge of the North Equatorial PanAfrican Belt,consists of quartzites,schists,micaschists,amphibolites,gneisses and migmatites.Tectonism has formed a landscape characterized by the development of linear and folded valleys and ridges,fault scarps,V-shaped valleys,incised rivers and knickpoints.These landforms constitute important markers of the regional tectonic activity,which have been computed from spatial sources such as SRTM,DEM,hydrographical networks and geomorphic indices such as AF,T,Smf,Vf,Bs,Hi,U,SI and Li.The results highlighted a mature relief consisting of asymmetric basins generated by tilting and uplift phenomena.The relative index of active tectonics(RIAT)has been estimated from an average of eight geomorphic indices evaluated on 24 subbasins,in the study area.Four classes have been defined:class 1(1.38),very high active(1.0≤RIAT<1.5);class 2(1.50-1.88),high active(1.5≤RIAT<2.0);and class 3(2.00-2.13)moderate active(2.0≤RIAT<2.5).These three classes,respectively covering 10.20%(458 km2),80.10%(3595 km2)and 9.69%(435 km2)of the study area,have shown a highly active tectonic zone,and imply the existence of a neotectonic event in the YG.This tectonic unit(YG)was also affected by the dextral NW-SE strike-slip faulting,which cross-cut the Sanaga Shear Zone(SSZ)at Ebebda and the foliation oriented NW-SE.The tilting and uplift of rocks related to Moho ascending are responsible for crustal thinning in the Cameroon basement,more important to the Adamawa Plateau from the Cretaceous age and the reactivation of existing tectonic accidents.The presence of hills,fault scarps,reverse faults,knickpoints,V and U shaped valleys and rounded mountains testify to the interaction between tectonic uplift,lithology,climate,weathering and erosion. 展开更多
关键词 landforms Geomorphic indices RIAT Active tectonics Yaounde Group
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Natural Walls of Anatolia: formation and development of Diş Kayalıkları as a structural landform (Sivas, Türkiye)
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作者 UZUN Ali AYLAR Faruk +3 位作者 ZEYBEK Halil Ibrahim GÜRGÖZE Serkan BAHADIR Muhammet ALEMDAĞ Selçuk 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1807-1823,共17页
The Diş Kayalıkları is one of the largest and most striking examples of crests in the world and is located between Eskidere and Boğazören villages of the İmranlı district of the Sivas province in Turkey. The cres... The Diş Kayalıkları is one of the largest and most striking examples of crests in the world and is located between Eskidere and Boğazören villages of the İmranlı district of the Sivas province in Turkey. The crests, which resemble castle walls when viewed from afar, have a real wall pattern due to the right-angled crack system of the bedrock when viewed closely. This study aims at investigating the geomorphological features of the Diş Kayalıkları and determining how the geological and geomorphological evolution of the Diş Kayalıkları took place and how the current formation mechanism continues. In the region, the mid-latitude continental climate prevails with cold humid winters and warm dry summers. The bedrock consists of Miocene bedded deposits of different resistance, folded by young tectonic movements. Diş Kayalıkları was formed by selective erosion of less resistant terrain around a pack of resistant rock on the steeper southern slope of an asymmetrical anticline. It has a length of 4750 m in the approximately northwest-southeast direction, a maximum height of 30 m, and a width varying between 5 and 8 m. In the present morphological appearance of the Diş Kayalıkları, it can be stated that the structure formed after the tectonic formation process was eroded under the control of the local climate and crest formation was realized. In the following process, the crest experienced a polycyclic process where different landforms were formed. There are smaller landforms such as karren, cave and rock window on Diş Kayalıkları, and macrofossil beds in some places. This highly attractive geomorphosite, unknown to wider public, should be investigated from various scientific aspects and should be brought to regional tourism by making the necessary infrastructure and promotion studies. 展开更多
关键词 Structural landform CREST Geosite DişKayalıkları Sivas
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Precipitation scale effect of the TRMM satellite in Tianshan,China
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作者 NING Shan ZHOU Hong-wu +2 位作者 ZHANG Zheng-yong BAI Shi-biao LIU Lin 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1349-1368,共20页
High-resolution precipitation data is conducive to objectively describe the spatial-temporal variability of regional precipitation,and the study of downscaling techniques and spatial scale effects can provide technica... High-resolution precipitation data is conducive to objectively describe the spatial-temporal variability of regional precipitation,and the study of downscaling techniques and spatial scale effects can provide technical and theoretical support to improve the spatial resolution and accuracy of satellite precipitation data.In this study,we used a machine learning algorithm combined with a regression algorithm RF-PLS(Random Forest-Partial Least Squares)to construct a downscaling model to obtain three types of high-resolution TRMM(Tropical Rainfall Measuring Mission)downscaled precipitation data for the years 2000-2017 at 250 m,500 m,and 1km.The scale effects with topographic and geomorphological features in the study area were analysed.Finally,we described the spatial and temporal variation of precipitation based on the optimal TRMM downscaled precipitation data.The results showed that:1)The linear relationships between the TRMM downscaled precipitation data obtained by each of the three downscaled models(PLS,RF,and RF-PLS)and the precipitation at the observation stations were improved compared to the linear relationships between the original TRMM data and the precipitation at the observation stations.The accuracy of the RF-PLS model was better than the other two models.2)Based on the RF-PLS model,the resolution of the TRMM data was increased to three different scales(250 m,500 m,and 1 km),considering the scale effects with topographic and geomorphological features.The precipitation simulation effect with a spatial resolution of 500 m was better than the other two scales.3)The annual precipitation was the highest in the areas with extremely high mountains,followed by the mediumhigh mountain,high mountain,medium mountain,medium-low mountain,plain,low mountain,and basin. 展开更多
关键词 TRMM data Scale effect LANDFORM Tianshan Mountains
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Hierarchical pattern recognition of landform elements considering scale adaptation
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作者 XU Yue-xue ZHU Hong-chun +1 位作者 LI Jin-yu ZHANG Sheng-jia 《Journal of Mountain Science》 SCIE CSCD 2023年第7期2003-2014,共12页
Landform elements with varying morphologies and spatial arrangements are recognized as feature indicator of landform classification and play a critical role in geomorphological studies.Differential geometry method has... Landform elements with varying morphologies and spatial arrangements are recognized as feature indicator of landform classification and play a critical role in geomorphological studies.Differential geometry method has been extensively applied in prior landform element research,while its efficacy in differentiating similar morphological characteristics remains inadequate to date.To reduce reliance on geomorphometric variables and increase awareness of landform patterns,geomorphons method was generated in previous study corresponding to specific landform reclassification map based on lookup table.Besides,to address the problem of feature similarity,hierarchical classification was proposed and effectively utilized for terrain recognition through the analytical strategy of fuzzy gradient features.Thus,combining the advantages of these two aspects,a hierarchical framework was proposed in this study for landform element pattern recognition considering the morphology and hierarchy factors.First,the local triplet patterns derived from geomorphons were enhanced by setting the flatness threshold,and subsequently adopted for the primary landform element recognition.Then,as geomorphic units with the same morphology possess different spatial analytical scales,the unidentified landform elements under the principle of scale adaptation were determined by calculating the spatial correlation and entropy information.To ensure the effectiveness of this proposed method,the sampling points were randomly selected from NASADEM data and then validated against a real 3D terrain model.Quantitative results of landform element pattern recognition demonstrate that our approach can reach above 77%average accuracy.Additionally,it delineates local details more effectively than geomorphons in visual assessment,resulting in a 7%accuracy improvement in overall scale. 展开更多
关键词 DEM Landform elements Hierarchical classification Scale adaptation Pattern recognition
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