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More Than Meets the Eye How the Honghe Hani Rice Terraces inspire a sustainable future
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作者 Guo Xixian Feng Jiahan 《China Report ASEAN》 2025年第10期26-28,共3页
French photographer Yann Layma first captured a moment at the Honghe Hani Rice Terraces in 1993.The tiered fields climbed like stairways into the sky.Glints of water appeared and disappeared through drifting clouds.Ha... French photographer Yann Layma first captured a moment at the Honghe Hani Rice Terraces in 1993.The tiered fields climbed like stairways into the sky.Glints of water appeared and disappeared through drifting clouds.Hani farmers could be seen quietly tending the land.Deeply moved,Layma spent six months producing Mountain Sculptors-a collection that included a film,a photo album,a travel diary,and nearly 10,000 photographs. 展开更多
关键词 Yann Layma tiered fields Hani farmers film Honghe Hani Rice terraces sustainable future mountain sculptors French photographer
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Trendy Terraces High on Fun Factor
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作者 DENG DI 《China Today》 2025年第9期56-58,共3页
AS twilight descended,a screen rose.Locals and tourists converged spontaneously on the open-air cinema on the second-floor terrace of Chang’an Mills shopping plaza,in the iconic Shougang Park,Beijing.If anything riva... AS twilight descended,a screen rose.Locals and tourists converged spontaneously on the open-air cinema on the second-floor terrace of Chang’an Mills shopping plaza,in the iconic Shougang Park,Beijing.If anything rivals the magic of a summer night sky,it’s the jovial atmosphere brought about by the silver screen. 展开更多
关键词 jovial atmosphere terrace shopping plaza iconic park magic atmosphere high fun factor open air cinema summer night sky silver screen
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Comparison of River Terraces in the Middle Reach Valleys of the Yellow River and Analysis on the Multi-Gradational Features of Tectonism in the Formation of Terrace Series
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作者 XingChengqi DingGuoyu +5 位作者 LuYanchou ShenXuhui TianQinjian YinGongming ChaiZhizhang WeiKaibo 《Earthquake Research in China》 2003年第2期183-198,共16页
Where the Yellow River flows through the Haiyuan-Tongxin arc-form tectonic region on the northeastern side of the Qinghai-Xizang (Tibet) Plateau, as many as 10~21 basis and erosion terraces have been produced, among ... Where the Yellow River flows through the Haiyuan-Tongxin arc-form tectonic region on the northeastern side of the Qinghai-Xizang (Tibet) Plateau, as many as 10~21 basis and erosion terraces have been produced, among which the biggest altitude above river level is 401m and the formation age of the highest terrace is 1.57 Ma B.P. Based on comparative analysis of the Yellow River terraces located separately in the Mijiashan mountain, the Chemuxia gorge, the Heishanxia gorge and the other river terraces in the vast extent of the northern part of China, it has been found that the tectonic processes resulting in the formation of the terrace series is one of multi-gradational features, i.e., a terrace series can include the various terraces produced by tectonic uplifts of different scopes or scales and different ranks. The Yellow River terrace series in the study region can be divided into three grades. Among them, in the first grade there are 6 terraces which were formed separately at the same time in the vast extent of the northern part of China and represent the number and magnitude of uplift of the Qinghai-Xizang Plateau since 1.6 Ma B. P.; in the second grade there are 5 terraces which were separately and simultaneously developed within the Haiyuan-Tianjingshan tectonic region and represent the number and magnitude of uplift of this tectonic region itself since 1.6Ma B.P.; in the third grade there are 10 terraces which developed on the eastern slope of the Mijiashan mountain and represent the number and amplitude of uplift of the Haiyuan tectonic belt itself since 1.6Ma B.P. Comparison of the terrace ages with loess-paleosoil sequence has also showed that the first grade terraces reflecting the vast scope uplifts of the Qinghai-Xizang Plateau are very comparable with climatic changes and their formation ages all correspond to the interglacial epochs during which paleosoils were formed. This implies that the vast extent tectonic uplifts resulting in river down-cutting are closely related to the warm-humid climatic periods which can also result in river downward erosion after strong dry and cold climatic periods, and they have jointly formed the tectonic-climatic cycles. There exists no unanimous and specific relationship between the formation ages of the second and third grade terraces and climatic changes and it is shown that the formation of those terraces was most mainly controlled by tectonic uplifts of the Tianjingshan block and the Haiyuan belt. The river terraces in the study region, therefore, may belong to 2 kinds of formation cause. One is a tectonic-climatic cyclical terrace produced jointly by vast extent tectonic uplifts and climatic changes, and the terraces of this kind are extensively distributed and can be well compared with each other among regions. Another is a pulse-tectonic cyclical terrace produced by local tectonic uplifts as dominant elements, and their distribution is restricted within an active belt and can not be compared with among regions. 展开更多
关键词 Comparison of river terraces Terrace series Multi-gradational features of tectonic process Origin of terraces Climatic changes The middle reaches of the Yellow River
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Research on Evaluation of Terrace Cultural Landscape Heritage Value from the Perspective of AVC——Take Three Famous Terraces in Southern China for Example 被引量:1
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作者 雷锦锦 罗盛锋 黄燕玲 《Agricultural Science & Technology》 CAS 2016年第12期2842-2846,2858,共6页
The objective evaluation to the terrace cultural landscape heritage value can provide targeted scientific basis for continuation of terrace culture landscape and establishment of protection measures. On the basis of f... The objective evaluation to the terrace cultural landscape heritage value can provide targeted scientific basis for continuation of terrace culture landscape and establishment of protection measures. On the basis of field investigation, expert consultation and literature review, combined with the AVC (Attraction、Vitality and Ca-pacity)theory and Analytic Hierarchy Process based on Fuzzy Comprehensive Evalu-ation, the terrace cultural landscape heritage protection evaluation system and eval-uation model, which selects 22 indicators from three levels including terrace culture landscape resources attraction, resources vitality and resources bearing capacity were structured. Based on col ection of data, material from field survey of China&#39;s most representative Yunnan Yuanyang Hani terrace, Hunan Ziquejie terrace and Longsheng Longji terrace and relevant mathematical calculation to determine evalua-tion index weights, organical y combined of qualitative with quantitative analysis, the diversity, reasonableness and accuracy of evaluation system is improved. Compre-hensive result of mathematical statistics showed that the rank of the cultural land-scape heritage value with the three most representative terraces in southern China is: γ(Hani)〉γ(Longji)〉γ(Ziquejie). 展开更多
关键词 Terrace cultural landscape heritage Value evaluation Analytic hierarchy process Fuzzy comprehensive evaluation
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Assessment of Soil Loss in the Mirabah Basin: An Overview of the Potential of Agricultural Terraces as Ancestral Practices (Saudi Arabia) 被引量:3
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作者 Naima Azaiez Ansar Alleoua +1 位作者 Narjes Baazaoui Nawal Qhtani 《Open Journal of Soil Science》 2020年第5期159-180,共22页
Water erosion remains the major problem in many countries, especially those with an extension in the arid and semi-arid area and those marked by a long dry season. The intensification of land degradation which is a re... Water erosion remains the major problem in many countries, especially those with an extension in the arid and semi-arid area and those marked by a long dry season. The intensification of land degradation which is a result of the strong erosive dynamics on a global scale has stimulated the initiative of multidisciplinary researchers investigate the issue of water erosion from its various facets [1] [2]. The goal is to preserve water and soil, two resources threatened. Multiple attempts were made to diagnose and implement empirical and experimental methods for quantitative estimation of soil loss caused by diffuse erosion. Indeed, the Eastern slope of the high mountains of Asir (Saudi Arabia), formerly worn and cut by the depression of rivers and undeniable branching of the river system, deserves to be studied in detail given the release of a huge erosive potential that is responsible for soil losses that are increasing gradually and continuously. The purpose of this paper was to validate the suitability of agricultural terraces in terms of soil preservation, using the results of the soil loss application as an indicator of the state of function of these latter. Many studies have addressed the agricultural terraces, however, only a few of them have focused on the relationship between erosion and agricultural terraces through an experimental approach. Previous work has concentrated mainly on their socio-economic impact;whilst the knowledge of their environmental impact remained scarce. In terms of the climate change context, soil erosion is becoming a central problem in Asir region. Thus, in this way, the application of the universal equation of soil loss was very helpful to explain and predict the role of each factor. Nevertheless, extreme caution and great care must be taken because of the application of this model outside its frame. 展开更多
关键词 AGRICULTURAL terraces Asir Drainage Density Sheet EROSION Mirabah WADI Universal Soil Loss Equation (USLE)
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Local perceptions of climate change and adaptation needs in the Ifugao Rice Terraces (Northern Philippines) 被引量:1
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作者 Mario A.SORIANO Jr. Johanna DIWA Srikantha HERATH 《Journal of Mountain Science》 SCIE CSCD 2017年第8期1455-1472,共18页
The Ifugao Rice Terraces in the Philippines is recognized worldwide as a sustainable landscape where humans live in harmony with nature. The success of the Ifugao Rice Terraces largely depends on the attunement of loc... The Ifugao Rice Terraces in the Philippines is recognized worldwide as a sustainable landscape where humans live in harmony with nature. The success of the Ifugao Rice Terraces largely depends on the attunement of local farmers to their environment and their ability to adapt to perceived changes, as manifested in their complex body of traditional ecological and climatic knowledge. This paper examines the local perceptions on climate change and other challenges to sustainability through focus group discussions with farmers and traditional knowledge holders. Our main findings can be summarized as follows:(i) Ifugao farmers were able to observe climatic changes in recent years, and these changes were intimately linked with broader environmental and socio-cultural changes in the Ifugao social-ecological system;(ii) The climatic changes qualitatively observed by the farmers were in agreement with trends in datasets commonly used in scientific assessments, although this agreement depends on the spatial and temporal resolution of the dataset, and the type of statistical analysis performed, and;(iii) The Ifugaos stressed the importance of traditional knowledge and culture in climate change adaptation, and preferred measures which could increase internal adaptive capacity while addressingbroader sources of community vulnerability. Our results support calls to recognize Indigenous and Western science as equally valid ways of knowing. Discussions with the farmers revealed that in the Ifugao context, climate change may be better framed in the context of multiple stressors on rural livelihoods, with adaptation integrated into broader development objectives. Our findings also emphasize the need for greater engagement of indigenous Ifugao people in planning processes in order to identify adaptation strategies that are culturally appropriate, equitable, and effective in responding to local needs. 展开更多
关键词 Ifugao RICE terraces Climate Change Traditional Knowledge Indigenous ADAPTATION Social-Ecological System Sustainability
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Tectonic and climatic controls for fluvial terraces of the Yellow River over the past 2.6 Ma at Northeast Tibetan Plateau and Ordos Block 被引量:1
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作者 GUO Xiao-hua FORMAN Steven +2 位作者 WANG Yuan-yuan ZHANG Yu-feng LIU Xin-yu 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2164-2180,共17页
The Yellow River is usually assumed to record tectonic activities and climatic changes;however,a systematic study was lack in the sedimentology,stratigraphy,geomorphology and geochronology for the entire Yellow River ... The Yellow River is usually assumed to record tectonic activities and climatic changes;however,a systematic study was lack in the sedimentology,stratigraphy,geomorphology and geochronology for the entire Yellow River though various geologic scholars have conducted numerous works in individual basins.This review focused on well-preserved fluvial terrace sequences that formed along this river on northeastern(NE)Tibetan Plateau and Ordos Block over the past 2.6 Ma.After comparing numerous initial incision ages at different segments along the Yellow River,we found out that the youngest initial incision may occur at ca.150 ka at the Longyang Gorge.The Yellow River may transit from multiple separated endorheic drainages to an entire external drainage after 150 ka,which may cause differentiations in the apparent incision rates before and after 150 ka;thus apparent net incision rates were calculated respectively for the Yellow River before 150 ka and the drainage network post 150 ka.Apparent net incision rates prior to 0.15 Ma were calculated as 0.15,0.29,0.10,0.12 and 0.03 mm/a respectively in Tongde-Xunhua,Lanzhou-Linxia basins,Heishan,Jinshan and Fenwei-Sanmen Gorges in this review,which mainly reflected Kunhuang-Gonghe Tectonic Event,generated by the Indo-Asian collision and diminishing as the NE Tibetan Plateau eastward extruding at ca.1.8-0.15 Ma.Apparent net incision rates post 0.15 Ma were calculated respectively for NE Tibetan Plateau and Ordos Block,considering their different base level.On NE Tibetan Plateau,four fluvial degradational phases were identified between ca.105~70,53~40,25~16 and 12~6 ka associated with terrace levels respectively,at average elevations of 96,40,20 and 10.5 meters above the current river level(m arl)within a range of 5~96 m arl;and four broad periods in the last 150 ka on Ordos Block:possibly marine oxygen isotope stage(MIS)5,ca.118 to 72 ka,most of MIS 3,ca.44~28 ka,transition from LGM to last deglacial ca.20 to 16 ka,and 4~3 ka at average elevations of 67.5,26,19 and 11.5 m arl.These degradational phases post 0.15 Ma were associated with multiple processes including enhanced fluvial discharge with an increase in monsoonal precipitation and/or melt water in deglaciation. 展开更多
关键词 Yellow River Fluvial terraces Tibetan Plateau Ordos Block Incision rate
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Origin and Distribution of Heavy Minerals in the Surficial and Subsurficial Sediments of the Alluvial Nile River Terraces 被引量:1
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作者 Magboul M. Sulieman Ibrahim S. Ibrahim +1 位作者 Jamal T. Elfaki Mohamed S. Dafa-Allah 《Open Journal of Soil Science》 2015年第12期299-310,共12页
Origin and distribution of the heavy minerals of surficial and subsurficial sediments has been investigated in the alluvial Nile River terraces, Khartoum North, Sudan. Heavy mineral assemblages in the very fine sand f... Origin and distribution of the heavy minerals of surficial and subsurficial sediments has been investigated in the alluvial Nile River terraces, Khartoum North, Sudan. Heavy mineral assemblages in the very fine sand fraction (0.063 - 0.125 mm) of 10 sediment samples were identified using petrography microscope. Results of descriptive statistical parameters revealed that most sediments samples belonged within very poorly sorted to extremely poorly sorted, strongly negative skewed to strongly positive skewed and mesokurtic to very leptokurtic. The quartz was the dominant in the opaque minerals in all sediments. The non-opaque heavy minerals were dominant by zircon, tourmaline, rutile, garnet, sillimanite, and andalusite. Results revealed that the ultrastable minerals (zircon, tourmaline and rutile) were found in all sediments with range from (2% - 47.36%, 2.08% - 29% and 3% - 24.99%), respectively. Garnet, sillimanite and andalusite were also found with range from (5% - 67%, 1% - 9.09% and 1% - 50%), respectively. Heavy mineral assemblage indentifies sources that are not bounded to the local origin. The proportion and presence of heavy minerals from outside source rocks indicated relatively strong reworking of zircon sand from the outer-shelf to inner-shelf as well relatively long distance of transport. Fluvial and Aeolian sediments were the dominant environments in the investigated area. We conclude that most heavy minerals in the study area are originally derived from gneisses and schist metamorphic rocks and some igneous rocks of the Ethiopian plateau. 展开更多
关键词 ALLUVIAL NILE River terraces Khartoum North PETROGRAPHY Microscope Aeolian Sediments ETHIOPIAN PLATEAU
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RESPONSE OF RIVER TERRACES TO HOLOCENE CLIMATIC CHANGES IN HEXICORRIDOR,GANSU,CHINA
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作者 李有利 杨景春 《Chinese Geographical Science》 SCIE CSCD 1998年第1期54-58,共0页
The Hexi Corridor is a Cenozoic foreland basin system at the northeast front of the Qinghai Xizang(Tibet) Plateau. The Shiyang River, Heihe River, Beida River and Shule River, rising in the Qilian Mountains, develop... The Hexi Corridor is a Cenozoic foreland basin system at the northeast front of the Qinghai Xizang(Tibet) Plateau. The Shiyang River, Heihe River, Beida River and Shule River, rising in the Qilian Mountains, developed two Holocene terraces each in the plain area of the Hexi Corridor. 14 C ages of alluvial fills show that the lower terraces formed between 5.57 ka B.P. and 3.15 ka B.P., the higher terraces formed between 12 ka B.P. and 8 ka B.P., and there was downcutting period from 8 ka B.P. to 6 ka B.P.. Comparing the alluvial terraces with the Holocene climatic changes, it is concluded that the downcutting period was coincident with the stable warmer and wetter climate, and the aggradation took place when the climate was changing either from drier to wetter or from wetter to drier. It is the climatic changes that caused the variations of vegetation density, soil erosion, and river sediment yields which controlled the aggradation and degradations of the rivers. 展开更多
关键词 RIVER terraces CLIMATIC CHANGES Hexi CORRIDOR
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Tertiary and Quaternary Marine Terraces and Planation Surfaces of Northern Oman:Interaction of Flexural Bulge Migration Associated with the Arabian-Eurasian Collision and Eustatic Sea Level Changes
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作者 Ye Yuan Timothy M.Kusky Sankaran Rajendran 《Journal of Earth Science》 SCIE CAS CSCD 2016年第6期955-970,共16页
The northeastern Arabian passive margin is being subducted beneath the Zagros and Makran of Iran. A flexural bulge related to the weight of the Makran has migrated at 4 cm/a through the previously uplifted Hajar Mount... The northeastern Arabian passive margin is being subducted beneath the Zagros and Makran of Iran. A flexural bulge related to the weight of the Makran has migrated at 4 cm/a through the previously uplifted Hajar Mountains of Oman as this active convergence and collision between Arabia and Eurasia progresses, adding approximately another 500 meters of relief, and forming a series of uplifted marine terraces, alluvial terraces, and planation surfaces that record the passage of the bulge. We use a combination of field studies, remote sensing and GIS to map and better-understand these terraces, and elucidate how the tectonics of bulge migration, down-to-trench normal faulting, and eustatic sea level changes have interacted to produce the extant geomorphic features on the inner slope of the flexural bulge as it sinks into the foredeep of the Gulf of Oman. We speculate those terraces that were uplifted on the outer slope of the forebulge as it initially migrated through the passive margin (affected by ophiolite obduction in the Cretaceous) 3.75-7.5 Ma ago are now sinking on the inner slope of the forebulge (corresponding to the outer trench slope in the foredeep), and have been partly covered by Quaternary marine terraces related to a Weichselian sea level high stand. Both the Tertiary and Quaternary terraces are cut by faults related to the active collision, confirming that there is a significant risk of moderate earthquakes in the region. 展开更多
关键词 marine terraces flexural bulge Arabia-Eurasia collision Sultanate of Oman remote sensing image processing Quaternary sea level fluctuation.
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First application of plutonium in soil erosion research on terraces
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作者 Yong-Jing Guan Wu Chen +12 位作者 Shen-Zhen Wang Yu-Xin Hua Qiao-Yan Jing Zhi-Yong Liu Chun-Ping Huang De-Yu Wang Hui-Juan Wang Xian-Wen He Mario De Cesare Liang-Jia Cui Hua He Kai-Di Fan Zi-Chen Guo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第4期41-53,共13页
The spatial distributions of ^(239+240)Pu and ^(137)Cs in soils from Longji Rice Terraces were investigated to evaluate soil erosion.The activity concentrations of ^(239+240)Pu and ^(137)Cs in the surface soils of the... The spatial distributions of ^(239+240)Pu and ^(137)Cs in soils from Longji Rice Terraces were investigated to evaluate soil erosion.The activity concentrations of ^(239+240)Pu and ^(137)Cs in the surface soils of the paddy fields were in the range of 0.089–0.734 and1.80–7.88 mBq/g,respectively.The activities of ^(239+240)Pu and ^(137)Cs showed very similar distribution trends,first increasing and then decreasing with increasing elevation.The 240Pu/239Pu atom ratios in the surface soils ranged from 0.162 to 0.232.The activities of ^(239+240)Pu and ^(137)Cs in the soil cores tended to be uniformly distributed within the plowed layer and declined exponentially below this depth.The mean soil erosion rates of Longji Rice Terraces estimated by ^(239+240)Pu and ^(137)Cs tracer methods were 5.44 t/(ha·a)and 5.16 t/(ha·a),respectively,which demonstrated that plutonium can replace ^(137)Cs as an ideal tracer for soil erosion research in the future.Landform features are the main factors affecting the distribution of plutonium and ^(137)Cs as well as soil erosion in the Longji Rice Terraces. 展开更多
关键词 Soil erosion PLUTONIUM ^(137)Cs Tracer method terraces
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Genesis and Classification of Some Soils of the River Nile Terraces: A Case Study of Khartoum North, Sudan
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作者 Magboul M. Sulieman Ibrahim S. Ibrahim Jamal T. Elfaki 《Journal of Geoscience and Environment Protection》 2016年第3期1-16,共16页
Soils developed in the alluvium terraces of the River Nile at Khartoum North, Sudan was analyzed in an attempt to classify it as well as to refer them to their origin. Three river terraces comprising nine profiles wer... Soils developed in the alluvium terraces of the River Nile at Khartoum North, Sudan was analyzed in an attempt to classify it as well as to refer them to their origin. Three river terraces comprising nine profiles were selected to cover the physiographic positions. Lack of B horizon and carbonate accumulation were main pedogenic processes in subsurface horizons, whereas orhric epipedon was developed on top soil surface. The microscopic inspection of heavy sand mineralogy indicated that the origin of the sand was the Ethiopian plateau. The most abundant clay mineral was smectite, followed by illite, kaolinite and chlorite. The presences of micas (illite) and chlorite in all studied soil samples might emphasize that these soils were young from the pedological viewpoint and less weathered. The soils of the River Nile terraces at Khartoum North were classified into: Typic Torrifluvents (1st terrace), Entic Haplocambids (2nd terrace) and Typic Haplocambids (3rd terrace). Mineralogy analysis indicated that the Entisols and Aridisols of the River Nile terraces in the study area had the same origin that of the igneous and metamorphic rocks from Ethiopian plateau. 展开更多
关键词 Pedogenesis Processes Ochric Epipedon River Nile terraces ENTISOLS ARIDISOLS Ethiopian Plateau
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Honghe Hani Rice Terraces
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《ChinAfrica》 2018年第6期60-61,共2页
On the south banks of the Honghe River in the mountainous terrain of south Yunnan, the Honghe Hani Rice Terraces cascade down the towering slopes of the Ailao Mountain. Carved out of dense forest over the past 1,300 y... On the south banks of the Honghe River in the mountainous terrain of south Yunnan, the Honghe Hani Rice Terraces cascade down the towering slopes of the Ailao Mountain. Carved out of dense forest over the past 1,300 years by Hani people since they settled here, the irrigated terraces support paddy fields surveying narrow valleys. In some places, there are as many as 3,000 terraces between thelower edges of the forest and the valley floor. 展开更多
关键词 Honghe Hani Rice terraces
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Terraces on Mount Ailao
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《China Today》 1998年第3期36-,41,共2页
TerracesonMountAilaoByLUOHAN&GUOJIANLINTHErollinghillsandsoar-ingpeaksofYunnanProvincearecoveredwithterraced... TerracesonMountAilaoByLUOHAN&GUOJIANLINTHErollinghillsandsoar-ingpeaksofYunnanProvincearecoveredwithterracedfields,someaslarg... 展开更多
关键词 terraces on Mount Ailao
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Analysis of Comprehensive Benefits of Transforming Slope Farmland to Terraces on the Loess Plateau:A Case Study of the Yangou Watershed in Northern Shaanxi Province,China 被引量:11
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作者 XU Yong YANG Bo +2 位作者 TANG Qing LIU Guobin LIU Puling 《Journal of Mountain Science》 SCIE CSCD 2011年第3期448-457,共10页
De-farming slope farmland has been an effective measure in recent years to improve environment and prevent soil and water loss on the Loess Plateau.There are different views about the defarming method,and also various... De-farming slope farmland has been an effective measure in recent years to improve environment and prevent soil and water loss on the Loess Plateau.There are different views about the defarming method,and also various de-farming patterns have been put into practice.This paper takes the Yangou Watershed in Shaanxi Province of China as a case for studying the comprehensive benefits of transforming slope farmland to terraces.Based on the day-by-day meteorological data of the Yan'an station in 2005 and the data of terrain features,soil and land use data of the Yangou Watershed,the impact of transforming slope farmland on terraces were simulated and analyzed in aspects of yield increase and water-soil conservation under different topographic conditions with the aid of software WIN-YIELD.Furthermore,an empirical analysis was applied to study the effects of transforming slope farmland to terraces in the Yangou Watershed.The results show that:(1) The bigger the topographic gradient is,the more remarkable benefits it has in yield increase and water-soil conservation.(2) Farmland with slope below 5° could be retained,but farmland with slope above 15° should be converted to forest or grassland as soon as possible.(3) Transforming slope farmland to terraces has the same remarkable effects as the current policy of "Relieving and de-farming" in improving agricultural production conditions,safeguarding food security,raising permanent vegetation coverage rate,and preventing soil and water loss.Besides,it is more cost-effective than the policy of "Relieving and de-farming".It's strongly suggested that the policy of transforming slope farmland to terraces be carried out on the Loess Plateau without delay. 展开更多
关键词 Slope farmland TERRACE Comprehensive benefits Yangou Watershed Loess Plateau
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Chronological Link Between the Abrupt Change of the Loess Grain Size Sequence and the Formation of River Terraces on the Eastern Margin of the Qinghai-Tibetan Plateau Since the Late Early-Pleistocene 被引量:4
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作者 LIU Dongyan QIAO Yansong +2 位作者 LI Weiran XIE Ruihuang PENG Shasha 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第3期723-732,共10页
Based on the study of magnetostratigraphy,magnetic susceptibility and grain size of Garze A section on the southeastern margin of the Qinghai-Tibetan Plateau since the late early-Pleistocene,the basal age of Garze loe... Based on the study of magnetostratigraphy,magnetic susceptibility and grain size of Garze A section on the southeastern margin of the Qinghai-Tibetan Plateau since the late early-Pleistocene,the basal age of Garze loess is located at~1.16 MaBP and a series of abrupt paleoclimatic changes is detected.The times of abrupt changes are of distinct series features,and the interval between each two adjacent abrupt changes is~50 kyr or~100 kyr.The most significant abrupt changes occur at around 1.06,0.85,0.6,0.46,0.39 and 0.14 MaBP.There is a chronological link between the abrupt changes of paleoclimate and the formation of river terraces and it is almost simultaneous with a strengthening trend of neotectonic activities.Therefore,maybe the climatic transition controll the timing of terrace formation,and the tectonic uplift originate potential energy and has a direct effect on channel incision, both the climatic transition and the tectonic uplift are important.Terraces are the products of the interaction of instable climatic variations and tectonic uplift.Like the loess-paleosol sequences,river terrace sequences are also controlled by the climate-tectonic coupling system and are ruled by climate-tectonic gyration with a~100 kyr paracycle,which may be the short eccentricity period of the earth. 展开更多
关键词 Garze loess grain size TERRACE tectonic uplift the Qinghai-Tibetan Plateau
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Formation of the Yalong Downstream Terraces in the SE Tibetan Plateau and Its Implication for the Uplift of the Plateau 被引量:4
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作者 HE Zexin ZHANG Xujiao +3 位作者 QIAO Yansong BAO Shuyan LU Chunyu HE Xiangli 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第2期542-560,共19页
The Yalong River is an important river that runs across the abruptly changing terrain of the SE Tibetan Plateau. The terraces and Quaternary sediments in its valleys preserve the information of tectonic uplift, climat... The Yalong River is an important river that runs across the abruptly changing terrain of the SE Tibetan Plateau. The terraces and Quaternary sediments in its valleys preserve the information of tectonic uplift, climate changes, and landform evolution since the Middle Pleistocene. Based on geomorphological, sedimentological, and chronological investigations, 6-8 terraces are identified in the lower reaches of Yalong catchment and its tributary--the Anning River. The electron spin resonance (ESR) or optically stimulated luminescence (OSL) data on the alluvial sediments in the upper portion of terraces indicate that they formed in 1.10, 0.90, 0.72, 0.06-0.04, 0.03-0.02, and 0.01 Ma. Tectonic uplift and the climatic cycle controlled the formation of the Yalong River terraces. The former dominated the dissection depths and incision rates, whereas the latter controlled the transformation between accumulation, which developed during the glacial period, and incision, which developed during the glacial-interglacial transition. The Yalong downstream incised rapidly from 1.10 to 0.72 Ma and rapidly from 0.06 Ma until the present; the terraces developed during these two periods. The incision rates in space during the two periods indicate the uplifting extent of the Jinpingshan area, which decreases toward the east and the south. The results reveal two rapidly uplifting stages in the SE Tibetan Plateau, including an accelerated uplifting since 0.06 Ma. Since the Middle Pleistocene, the tectonic uplift of the SE and NE parts of the Tibetan Plateau is synchronous, according to the same development stages of the river terraces of the Yalong downstream and the Yellow River in the Lanzhou area of the NE Tibetan Plateau. The difference in the horizontal displacement between the Xianshuihe Fault and the Anninghe Fault bend resulted in the rapid uplift of the Jinpingshan area. The incision rate for the spatial distribution of the Yalong downstream is the geomorphologicai response of crustal shortening and uplift differences in the SE margin block of the Tibetan Plateau. The southeastward diffusion process of the Tibetan Plateau was recorded. 展开更多
关键词 Yalong downstream Anning River river terrace tectonic uplift climate change the Tibetan Plateau
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Sequences and genesis of the Yellow River terraces from Sanmen Gorge to Kouma 被引量:4
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作者 苏怀 王均平 +2 位作者 潘保田 明庆忠 李琼 《Journal of Geographical Sciences》 SCIE CSCD 2009年第3期351-358,共8页
Based on field landscape investigations, thermoluminescence (TL), magnetostratigraphy and Ioess-paleosol sequence, we found that there are at least four Yellow River terraces, whose ages are 0.86 Ma, 0.62 Ma, 0.13 M... Based on field landscape investigations, thermoluminescence (TL), magnetostratigraphy and Ioess-paleosol sequence, we found that there are at least four Yellow River terraces, whose ages are 0.86 Ma, 0.62 Ma, 0.13 Ma and 0.05 Ma, in Yuxi Fault-Uplift (from Sanmen Gorge to Mengjin) and at least three Yellow River terraces, whose ages are 1.24 Ma, 0.25 Ma and 0.05 Ma, in Huabei Fault Depression (from Mengjin to Kouma). All the terraces have a similar structure that several meters of paleosols directly develop on the top of fluvial silt. It shows that the Yellow River incised and consequently abandoned floodplain converted to terrace during the interglacial period. Therefore, there may be a link between the formation of terraces and glacial-interglacial climatic cycles. However, the differences in the Yellow River terrace sequences and ages between Yuxi Fault-Uplift and Huabei Fault Depression indicate that the surface uplift should play an important role in the formation of these terraces. 展开更多
关键词 Sanmen Gorge Yellow River terrace climatic changes surface uplift
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Performance of Farmland Terraces in Maintaining Soil Fertility: A Case of Lake Maybar Watershed in Wello, Northern Highlands of Ethiopia 被引量:4
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作者 Shimeles Damene Lulseged Tamene Paul L.G. Vlek 《Journal of Life Sciences》 2012年第11期1251-1261,共11页
Soil-erosion-induced land degradation is a great challenge in the Ethiopian highlands. Consequently, the government has invested in soil and water conservation measures to tackle the problem where farmland terracing i... Soil-erosion-induced land degradation is a great challenge in the Ethiopian highlands. Consequently, the government has invested in soil and water conservation measures to tackle the problem where farmland terracing is one of the commonly implemented measures in the country. The purpose of this study was to analyze the role of farmland terracing in maintaining soil fertility and to evaluate its performance within a terrace, across terrace age and slope of terrain. The study was conducted in the Lake Maybar watershed in Wello, northern Ethiopia. Composite topsoil samples were collected from plots representing four slope categories across the terrain and three positions within a terrace. The samples were analyzed for selected soil physico-chemical properties and statistically tested using ANOVA (analysis of variance). The study revealed that soil pH (△pH [H2O] = 0.6), exchangeable K+ (△K+ = 0.33 cmol(+)/kg) and clay (9%) content significantly increased towards the lower terrain position. Unlike other studies, all soil properties except bulk density (△ 0.40 g/cm3) showed non-significant differences within a terrace. Bench terrace formation reduced soil fertility gradients within a terrace for which it has been commented. Soil fertility also showed very slight change across terrace age, which indicates terracing reduced erosion-induced soil and nutrient loss. However, in order to optimize impact of farmland terracing on soil fertility maintenance, terracing should be complemented by fertility amendment considering site-specific conditions. 展开更多
关键词 Farmland terrace TERRAIN Wello Ethiopia soil degradation soil fertility.
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Evaluation of water resources conserved by forests in the Hani rice terraces system of Honghe County,Yunnan,China:an application of the fuzzy comprehensive evaluation model 被引量:13
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作者 LI Jing MIN Qingwen +3 位作者 LI Wenhua BAI Yanying YANG Lun Dhruba Bijaya G C 《Journal of Mountain Science》 SCIE CSCD 2016年第4期744-753,共10页
The Hani Rice Terraces System, based on gravity-flow irrigation, is one of the Globally Important Agricultural Heritage Systems(GIAHS) pilot sites selected by FAO in 2010. The water resource plays an important role in... The Hani Rice Terraces System, based on gravity-flow irrigation, is one of the Globally Important Agricultural Heritage Systems(GIAHS) pilot sites selected by FAO in 2010. The water resource plays an important role in the sustainable development of this system. The value of water conserved by the forest is influenced by natural, economic and social factors. In this paper, the water quality, per capita water resources, per capita GDP and population density are chosen as indices to construct an index system for a comprehensive evaluation of water resources value. The weights of these indices are 0.443, 0.31, 0.141 and 0.106 respectively, which are determined by the analytic hierarchy process(AHP) method. The water resources value has been assessed by the fuzzy comprehensive evaluation model. The results show that the water resources value in the Hani Rice Terraces System is 4.25 RMB/m^3. Evaluating the value of water resources in the Hani Rice Terraces System can provide a reference for ecological compensation, for raising public awareness of the importance of protecting the system, and ultimately achieving its sustainable development. 展开更多
关键词 Fuzzy comprehensive evaluation model Water resources Hani Rice Terrace Water value Globally Important Heritage Systems(GIAHS)
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