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THE ENVIRONMENTAL QUALITY AND RENOVATING PLAN OF THE LOESS PLATEAU AND LIUPANSHAN MOUNTAINOUS AREA IN NINGXIA
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作者 Chen Jisen Ningxia Research Institute of Environmental Protection, Yinchuan 《干旱区资源与环境》 CSCD 1993年第Z1期480-483,共4页
1. The environmental quality of the Loess Plateau and Liupanshan mountainous area in Ningxia The landuse structure in the studied region was very irrational in 1970s, the propor-tions covered by farming, forestry and ... 1. The environmental quality of the Loess Plateau and Liupanshan mountainous area in Ningxia The landuse structure in the studied region was very irrational in 1970s, the propor-tions covered by farming, forestry and animal husbandry are separately 50.91%, 6.32% and33.3%. Since 1980s, the farmland has been returned back to forestry and pasture so that 展开更多
关键词 the loess plateau Liupanshan MOUNTAINS Environmental Qulity
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Characteristics of root pullout resistance of Caragana korshinskii Kom.in the loess area of northeastern Qinghai-Tibet Plateau,China 被引量:3
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作者 LIU Yabin SHI Chuan +5 位作者 YU Dongmei WANG Shu PANG Jinghao ZHU Haili LI Guorong HU Xiasong 《Journal of Arid Land》 SCIE CSCD 2022年第7期811-823,共13页
Roots exert pullout resistance under pullout force,allowing plants to resist uprooting.However,the pullout resistance characteristics of taproot-type shrub species of different ages remain unclear.In this study,in ord... Roots exert pullout resistance under pullout force,allowing plants to resist uprooting.However,the pullout resistance characteristics of taproot-type shrub species of different ages remain unclear.In this study,in order to improve our knowledge of pullout resistance characteristics of taproot systems of shrub species,we selected the shrub species Caragana korshinskii Kom.in different growth periods as the research plant and conducted in situ root pullout test.The relationships among the maximum pullout resistance,peak root displacement,shrub growth period,and aboveground growth indices(plant height and plant crown breadth)were analyzed,as well as the mechanical process of uprooting.Pullout resistance of 4-15 year-old C.korshinskii ranged from 2.49(±0.25)to 14.71(±4.96)kN,and the peak displacement ranged from 11.77(±8.61)to 26.50(±16.09)cm.The maximum pullout resistance and the peak displacement of roots increased as a power function(R^(2)=0.9038)and a linear function(R^(2)=0.8242)with increasing age,respectively.The maximum pullout resistance and the peak displacement increased with increasing plant height;however,this relationship was not significant.The maximum pullout resistance increased exponentially(R^(2)=0.5522)as the crown breadth increased.There was no significant relationship between the peak displacement and crown breadth.The pullout resistance and displacement curve were divided into three stages:the initial nonlinear growth,linear growth,and nonlinear stages.Two modes of failure of a single root occurred when the roots were subjected to vertical loading forces:the synchronous breakage mode and the periderm preferential breakage mode.These findings provide a foundation for further investigation of the soil reinforcement and slope protection mechanisms of this shrub species in the loess area of northeastern Qinghai-Tibet Plateau,China. 展开更多
关键词 loess area Qinghai-Tibet plateau pullout resistance growth period aboveground growth indices pullout test Caragana korshinskii
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Migration and speciation transformation mechanisms of mercury in undercurrent zones of the Tongguan gold mining area, Shaanxi Loess Plateau and impact on the environment 被引量:5
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作者 Rui-ping Liu You-ning Xu +2 位作者 Hui-chao Rui El-Wardany RM Ying Dong 《China Geology》 2021年第2期311-328,共18页
In order to study the migration and transformation mechanism of Hg content and occurrence form in subsurface flow zone of gold mining area in Loess Plateau and its influence on water environment,the field in-situ infi... In order to study the migration and transformation mechanism of Hg content and occurrence form in subsurface flow zone of gold mining area in Loess Plateau and its influence on water environment,the field in-situ infiltration test and laboratory test were carried out in three typical sections of river-side loess,alluvial and proluvial strata in Tongguan gold mining area of Shaanxi Province,and the following results were obtained:(1)The source of Hg in subsurface flow zone is mainly caused by mineral processing activities;(2)the subsurface flow zone in the study area is in alkaline environment,and the residual state,iron and manganese oxidation state,strong organic state and humic acid state of mercury in loess are equally divided in dry and oxidizing environment;mercury in river alluvial or diluvial strata is mainly concentrated in silt,tailings and clayey silt soil layer,and mercury has certain stability,and the form of mercury in loess is easier to transform than the other two media;(3)under the flooding condition,most of mercury is trapped in the silt layer in the undercurrent zone where the sand and silt layers alternate with each other and the river water and groundwater are disjointed,and the migration capacity of mercury is far less than that of loess layer and alluvial layer with close hydraulic connection;(4)infiltration at the flood level accelerates the migration of pollutants to the ground;(5)the soil in the undercurrent zone is overloaded and has seriously exceeded the standard.Although the groundwater monitoring results are safe this time,relevant enterprises or departments should continue to pay attention to improving the gold extraction process,especially vigorously rectify the small workshops for illegal gold extraction and the substandard discharge of the three wastes,and intensify efforts to solve the geological environmental problems of mines left over from history.At present,the occurrence form of mercury in the undercurrent zone is relatively stable,but the water and soil layers have been polluted.The risk of disjointed groundwater pollution can not be ignored while giving priority to the treatment of loess and river alluvial landform areas with close hydraulic links.The research results will provide a scientific basis for water conservancy departments to groundwater prevention and control in water-deficient areas of the Loess Plateau. 展开更多
关键词 Mercury speciation Hyporheic zones Constant surface water level Flood level Surface-groundwater Hydraulic connection Tongguan gold mining areas loess plateau Shannxi Province
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Remote Sensing Monitoring of the Subalpine Coniferous Forests and Quantitative Analysis of the Characteristics of Succession in East Mountain Area of Tibetan Plateau——A Case Study With Zamtang County 被引量:5
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作者 张学儒 张镱锂 +2 位作者 刘林山 张继平 高俊刚 《Agricultural Science & Technology》 CAS 2011年第6期926-930,共5页
The study area lies in the Dadu River drainage area in upstream Yangtze River.The spatial distribution of subalpine coniferous forests in 1989 and 2009 was extracted by means of a combined method of object orientation... The study area lies in the Dadu River drainage area in upstream Yangtze River.The spatial distribution of subalpine coniferous forests in 1989 and 2009 was extracted by means of a combined method of object orientation and visual interpretation,and then the overlaying analysis of these data was conducted.The type and spatial location of succession were discovered and served as the sample of dependant variable.Meanwhile,supported by GIS technology and based on DEM and thematic data,the eight variables including altitude,slope,sin and cosin of aspect,curvity of land surface,and distance to residential area,cultivated land and road were extracted served as the sample of spatial succession of subalpine coniferous forests to fit Logistic Regression,and then the contribution of each independent variable as well as the spatial property of the occurrence probability of succession was calculated.The results suggested that,during the succession of subalpine coniferous forests to meadow,the closer to the residential area and cultivated land,the greater the contribution to succession is.In particular,when the distance to the residential area decreases by one unit,the probability for its conversion to meadow will be increased by 1.15 times.During the succession of subalpine coniferous forests to deciduous-broadleaved shrubs,the sin of aspect and distance to residential area contribute more,and the probability of succession increases with increasing degree of northwardness,i.e.when the degree of northwardness increases by one unit,the probability will be increased by 1.2 times.The quantitative analysis of spatial succession property of subalpine coniferous forests will supply scientific basis to the protection and restoration of subalpine coniferous forests. 展开更多
关键词 Subalpine Coniferous Forests Logistic Regression GIS East Mountain area of Tibetan plateau
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Growth behavior and resource potential evaluation of gas hydrate in core fractures in Qilian Mountain permafrost area, Qinghai-Tibet Plateau 被引量:1
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作者 Qing-guo Meng Chang-ling Liu +5 位作者 Zhen-quan Lu Xi-luo Hao Cheng-feng Li Qing-tao Bu Yun-kai Ji Jia-xian Wang 《China Geology》 CAS CSCD 2023年第2期208-215,共8页
The Qilian Mountain permafrost area located in the northern of Qinghai-Tibet Plateau is a favorable place for natural gas hydrate formation and enrichment,due to its well-developed fractures and abundant gas sources.U... The Qilian Mountain permafrost area located in the northern of Qinghai-Tibet Plateau is a favorable place for natural gas hydrate formation and enrichment,due to its well-developed fractures and abundant gas sources.Understanding the formation and distribution of multi-component gas hydrates in fractures is crucial in accurately evaluating the hydrate reservoir resources in this area.The hydrate formation experiments were carried out using the core samples drilled from hydrate-bearing sediments in Qilian Mountain permafrost area and the multi-component gas with similar composition to natural gas hydrates in Qilian Mountain permafrost area.The formation and distribution characteristics of multi-component gas hydrates in core samples were observed in situ by X-ray Computed Tomography(X-CT)under high pressure and low temperature conditions.Results show that hydrates are mainly formed and distributed in the fractures with good connectivity.The ratios of volume of hydrates formed in fractures to the volume of fractures are about 96.8%and 60.67%in two different core samples.This indicates that the fracture surface may act as a favorable reaction site for hydrate formation in core samples.Based on the field geological data and the experimental results,it is preliminarily estimated that the inventory of methane stored in the fractured gas hydrate in Qilian Mountain permafrost area is about 8.67×1013 m3,with a resource abundance of 8.67×108 m3/km2.This study demonstrates the great resource potential of fractured gas hydrate and also provides a new way to further understand the prospect of natural gas hydrate and other oil and gas resources in Qilian Mountain permafrost area. 展开更多
关键词 Gas hydrate Growth behavior Core fracture Rock Quality Designation Resource potential evaluation Engineering Oil and gas exploration Qilian Mountain permafrost area Qinghai-Tibet plateau
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Selection of Indigenous Plants in Roads in Northwestern Loess Plateau Area
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作者 张铁军 王春玲 《Agricultural Science & Technology》 CAS 2012年第3期583-591,共9页
[Objective] The aim was to study on resource utilization of indigenous plants in roads in order to solve resource shortage of indigenous plant in bioengi- neering. [Method] Based on northwestern loess plateau area, we... [Objective] The aim was to study on resource utilization of indigenous plants in roads in order to solve resource shortage of indigenous plant in bioengi- neering. [Method] Based on northwestern loess plateau area, we conducted research on selection of indigenous plants and survey on the species which could live in adverse condition, mainly by surveying, with frequent tests as a supplement, to make a comprehensive observation and evaluation on plant combinations which are to be extensively applied. [Result] The research indicated that in central dividing strips, four arbors, including Platycladus orientalis (Linn.)Franco, Sabina chinensis, Sabinachinen- sis(Linn.)Ant., and Ulmus purnila L., and nine frutices, including Lycium chinense, Tamarix austromongolica, Rosa xanthina Lindl., Forsythia suspense, Atriplex canescens, Amygdalus triloba, Hippophae rharnnoides Linn., Arnorpha fruticosa L., and Syzygium aromaticum could be planted. In addition, Gleditsia sinensis Lain, Robinia pseudoacacia L, Elaeagnus angustifolia L., Rhus typhina, Salix babylonica, Salixmatsudana and Fraxinus chinensis, tall and strong, are suitable to be planted as border trees, presenting a good vision. Frutices, limited by height, are usually with more branches, which will provide a good landscape if grown with tall plants. Prunus dacidiana and Ulmus pumila L., prone to be damaged by insects, should be planted with other species to stop the infestation in space. [Conclusion] The research laid foundation for selection of indigenous plants in roads, providing references for resource shortage of indigenous plant for bioengineedng. 展开更多
关键词 loess plateau area ROAD Indigenous plant SELECTION Plant combination
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The effects of land use and its patterns on soil properties in a small catchment of the Loess Plateau 被引量:6
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作者 WANGJun FUBo-jie 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第2期263-266,共4页
Due to relatively strong human activities in the hilly area of Loess Plateau, the natural vegetation has been destroyed, and landscape pattern based on agricultural land matrix was land use mosaic composing of shrub l... Due to relatively strong human activities in the hilly area of Loess Plateau, the natural vegetation has been destroyed, and landscape pattern based on agricultural land matrix was land use mosaic composing of shrub land, grassland, woodland and orchard. This pattern has an important effect on soil moisture and soil nutrients. The Danangou catchment, a typical small catchment, was selected to study the effects of land use and its patterns on soil moisture and nutrients in this paper. The results are as follows: The comparisons of soil moisture among seven land uses for wet year and dry year were performed: (1) the average of soil moisture content for whole catchment was 12.11% in wet year, while it was 9.37% in dry year; (2) soil moisture among seven land uses was significantly different in dry year, but not in wet year; (3) from wet year to dry year, the profile type of soil moisture changed from decreasing type to fluctuation-type and from fluctuant type to increasing type; (4) the increasing trend in soil moisture from the top to foot of hillslope occurred in simple land use along slope, while complicated distribution of soil moisture was observed in multiple land uses along slope. The relationships between soil nutrients and land uses and landscape positions were analysed: (1) five nutrient contents of soil organic matter (SOM), total N (TN), available N (AN), total P (TP) and available P (AP) in hilly area were lower than that in other areas. SOM content was less than 1%, TN content less than 0.07%, and TP content between 0.05% and 0.06%; (2) SOM and TN contents in woodland, shrub land and grassland were significantly higher than that in fallow land and cropland, and higher level in soil fertility was found in crop-fruit intercropping land among croplands; (3) soil nutrient distribution and responses to landscape positions were variable depending on slope and the location of land use types. 展开更多
关键词 hilly area of loess plateau land use pattern soil moisture soil nutrient
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Erosion environment in the sediment-rich area on the Loess Plateau 被引量:3
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作者 JIAO Ju-ying, LI Jing, WANG Wan-zhong (Institute of Soil and Water Conservation, CAS and Ministry of Water Resources Northwest Sci-techonology University of Agriculture and Forestry, Yangling 712100, China) 《Journal of Geographical Sciences》 SCIE CSCD 2002年第1期49-57,共9页
Based on the investigation and analysis of characteristics of precipitation, natural environment, socio-economic factors and soil erosion, this paper indicates that the precipitation is the main driving force for the ... Based on the investigation and analysis of characteristics of precipitation, natural environment, socio-economic factors and soil erosion, this paper indicates that the precipitation is the main driving force for the soil erosion in the sediment-rich area, its variability determines the characteristics of soil and water loss; the natural conditions such as the drainage systems, geological and topographic features, the composition of soil and land surface materials, vegetation and climate determine the seriousness of soil and water loss; irrational socio-economic activities of human beings usually accelerated soil and water loss; meanwhile, the low preservation rate and inferiority of soil and water conservation measures made it impossible to make rapid progress on soil and water loss control. Furthermore, the characteristics of erosion environment endowed this area with more sediment that is the main reason for the flooding disasters by the Yellow River. Therefore, more emphasis should be placed on the enhancement of soil and water conservation. The soil loss prediction models will provide scientific basis for the planning of soil and water conservation, the designing of soil and water conservation measures and the valuation of effects of soil and water loss control. According to the analysis of the previous studies on soil loss prediction, and the water-sediment variation features, it is thought that study on soil loss prediction under various rainfall conditions and soil-water conservation measures should be carried out. 展开更多
关键词 loess plateau sediment-rich area soil erosion environmental characteristics
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Relationship Between Agriculture and Ecological Deterioration,Restoration and Reconstruction in Loess Plateau Areas of Northwest China 被引量:2
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作者 CHENG Xu( China Agricultural University, Beijing 100094) 《Agricultural Sciences in China》 CAS CSCD 2002年第1期114-120,共7页
A comprehensive analysis was conducted on the current situation as well as historic succession processor agriculture and ecological conditions in Northwest China, in particular in the Loess Plateau, by means of a inte... A comprehensive analysis was conducted on the current situation as well as historic succession processor agriculture and ecological conditions in Northwest China, in particular in the Loess Plateau, by means of a inter-disciplinary approach of ecology, agro-geohistory, and agronomy. It was concluded that the fundamental causes responsible for the ecological deterioration, signed by the poor agro-productivity and serious soil erosion, had been the extensive cropping system by ever-increasing reclamation on semi-drought slope land, where initiated a natural vegetation of brushy grasses with sparse trees, thus suitable only for animal husbandry. Based on an identification of specific actual status of China, several countermeasures of correctly dealing with the relationship between agricultural development and the ecological restoration and reconstruction were proposed, including to get breakthrough first in the transection area by means of the rational use of resources and the raising of agro-system productivity, to promoting 'water conservancy-type ecological agriculture' through the radical shift of traditional production pattern, and the adoption of a policy of proper degree of grain self-reliance, as well as to construct livestock industry base in Northwest China. 展开更多
关键词 loess plateau area of Northwest China Agricultural ecology
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Response of glacier area variation to climate change in the Kaidu-Kongque river basin,Southern Tianshan Mountains during the last 20 years 被引量:4
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作者 Lu-chen Wang Kun Yu +9 位作者 Liang Chang Jun Zhang Tao Tang Li-he Yin Xiao-fan Gu Jia-qiu Dong Ying Li Jun Jiang Bing-chao Yang Qian Wang 《China Geology》 2021年第3期389-401,共13页
Glaciers are crucial water resources for arid inland rivers in Northwest China.In recent decades,glaciers are largely experiencing shrinkage under the climate-warming scenario,thereby exerting tremendous influences on... Glaciers are crucial water resources for arid inland rivers in Northwest China.In recent decades,glaciers are largely experiencing shrinkage under the climate-warming scenario,thereby exerting tremendous influences on regional water resources.The primary role of understudying watershed scale glacier changes under changing climatic conditions is to ensure sustainable utilization of regional water resources,to prevent and mitigate glacier-related disasters.This study maps the current(2020)distribution of glacier boundaries across the Kaidu-Kongque river basin,south slope of Tianshan Mountains,and monitors the spatial evolution of glaciers over five time periods from 2000-2020 through thresholded band ratios approach,using 25 Landsat images at 30 m resolution.In addition,this study attempts to understand the role of climate characteristics for variable response of glacier area.The results show that the total area of glaciers was 398.21 km^(2)in 2020.The glaciers retreated by about 1.17 km^(2)/a(0.26%/a)from 2000 to 2020.The glaciers were reducing at a significantly rapid rate between 2000 and 2005,a slow rate from 2005 to 2015,and an accelerated rate during 2015-2020.The meteorological data shows slight increasing trends of mean annual temperature(0.02℃/a)and annual precipitation(2.07 mm/a).The correlation analysis demonstrates that the role of temperature presents more significant correlation with glacier recession than precipitation.There is a temporal hysteresis in the response of glacier change to climate change.Increasing trend of temperature in summer proves to be the driving force behind the Kaidu-Kongque basin glacier recession during the recent 20 years. 展开更多
关键词 Glacier area Climate change Remote sensing monitoring Hydrogeological survey engineering Kaidu-Kongque river basin Tianshan Mountains Center Asia-Mongolian plateau
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THE SYSTEMATIC DYNAMIC EMULATION ON THE AGRICULTURAL DEVELOPMENT ON THE LOESS PLATEAU
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作者 Lin Haiming Huang Gaobao +1 位作者 Chen Yuan Yu Shiming Gansu Agricultural University, Lanzhou, 730070 《干旱区资源与环境》 CSCD 1993年第Z1期471-475,共5页
The Loess Plateau, covered with thick loess, lies in the middle reaches of the YellowRiver to the west of the Taihangshan Mountains, east of the Wuqiao Mountains south ofYinshan Mountains and north of the Qinling Moun... The Loess Plateau, covered with thick loess, lies in the middle reaches of the YellowRiver to the west of the Taihangshan Mountains, east of the Wuqiao Mountains south ofYinshan Mountains and north of the Qinling Mountains with a total area of 56×10~4km^2.The plateau is 1000--2500m above sea level and has loess as thick as 100--200 metres, be- 展开更多
关键词 the loess plateau SEMIARID area Agricultural Region Systematic Dynamics EMULATION Study
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Late Cenozoic uplift of the Liupan Mountains:Evidence from the Neogene loess deposits
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作者 Zhilin HE Yansong QIAO +8 位作者 Zhengtang GUO Chaoqin CHEN Long CHEN Yang FU Ye YANG Yanxia LIANG Xinru LIN Guoqiao XIAO Tao ZHAN 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第5期1480-1488,共9页
The Liupan Mountains,one of the important mountain ranges in western China,are located on the boundary between the northeastern Tibetan Plateau and the Ordos Block.The uplift history of the Liupan Mountains remains co... The Liupan Mountains,one of the important mountain ranges in western China,are located on the boundary between the northeastern Tibetan Plateau and the Ordos Block.The uplift history of the Liupan Mountains remains controversial.Loess deposits are good tracers of regional tectonic and geomorphic changes,because loess is sensitive to erosion and the formation and preservation of loess requires relatively flat highlands and relatively stable tectonic environments.We investigated the distribution of Neogene loess deposits on the western piedmont of the Liupan Mountains and examined a near-continuous loess section(Nanping section)on the piedmont alluvial highlands.Correlation of magnetic susceptibility stratigraphy with the QA-ⅠMiocene loess sequence dates this 56-m section covering the interval from~8.1 to 6.2 Ma.The lower boundary age of this section,together with previously reported Zhuanglang red clay(sand-gravel layers with intercalated loess during~9–8 Ma and near-continuous loess during~8–4.8 Ma)and Chaona red clay(~8.1–2.58 Ma),indicates that the Liupan Mountains were uplifted in the late Miocene(~9–8 Ma)and basically formed by~8 Ma,attesting to no intense mountain building since that time.In addition,based on the information from the Zhuanglang core and the QA-Ⅰsection,we infer that sizable parts of the Liupan Mountains were uplifted during the late Oligocene–early Miocene and did not experience intense uplift during~22–9 Ma. 展开更多
关键词 Liupan Mountains Mountain building Neogene loess Chinese loess plateau Late Miocene Late Oligocene–early Miocene
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Spatial-temporal Pattern and Population Driving Force of Land Use Change in Liupan Mountains Region, Southern Ningxia, China 被引量:15
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作者 QUAN Bin M J M ROMKENS +4 位作者 TAO Jianjun LI Bicheng LI Chaokui YU Guanghui CHEN Qichun 《Chinese Geographical Science》 SCIE CSCD 2008年第4期323-330,共8页
The Liupan Mountains is located in the southern Ningxia Hui Autonomous Region of China, which forms an important dividing line between landforms and bio-geographic regions. The populated part of the Liupan Mountains r... The Liupan Mountains is located in the southern Ningxia Hui Autonomous Region of China, which forms an important dividing line between landforms and bio-geographic regions. The populated part of the Liupan Mountains region has suffered tremendous ecological damages over time due to population pressure, excessive demand and inappropriate use of agricultural land resources. In this paper, datasets of land use between 1990 and 2000 were obtained from Landsat TM imagery, and then spatial models were used to characterize landscape conditions. Also, the relationship between the population density and land use/cover change (LUCC) was analyzed. Results indicate that cropland, forestland, and urban areas have increased by 44,186ha, 9001ha and 1550ha, respectively while the grassland area has appreciably decreased by 54,025ha in the study period. The decrease in grassland was most notable. Of the grassland lost, 49.4% was converted into cropland. The largest annual land conversion rate in the study area was less than 2%. These changes are attributed to industrial and agricultural development and population growth. To improve the eco-economic conditions in the study region, population control, urbanization and development of an ecological friendly agriculture were suggested. 展开更多
关键词 land use/cover change (LUCC) GIS remote sensing Liupan Mountains region loess plateau
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我国黄土高原地区地震动衰减关系研究的若干进展 被引量:1
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作者 薄景山 万卫 +2 位作者 彭达 段玉石 李琪 《地震工程学报》 CSCD 北大核心 2024年第1期182-198,共17页
地震动的衰减关系是指地震动随震级、距离和场地条件等变化的经验关系,近年来在我国亦被称为地震动预测方程,是估计地震动及其影响场的主要方法之一,在地震区划和重大工程场地地震安全性评价中被广泛应用。黄土是一种特殊土,在我国广泛... 地震动的衰减关系是指地震动随震级、距离和场地条件等变化的经验关系,近年来在我国亦被称为地震动预测方程,是估计地震动及其影响场的主要方法之一,在地震区划和重大工程场地地震安全性评价中被广泛应用。黄土是一种特殊土,在我国广泛分布。我国黄土高原地区地质构造复杂,新构造活动强烈,中强地震频发,地震动的衰减关系有其特殊性,总结我国黄土高原地区地震动衰减关系的研究成果对促进黄土高原地区抗震研究有重要意义。在简要介绍国内外地震动衰减关系研究的基础上,全面系统地总结我国学者在黄土高原地区的地震烈度衰减关系,基岩和土层场地地震动峰值加速度、峰值速度、峰值位移以及反应谱衰减关系方面的研究成果;评述和讨论在黄土覆盖地区地震动衰减研究领域存在的问题和今后的研究方向。文章的研究工作对从事黄土高原地区地震工程研究的科技人员有重要参考价值。 展开更多
关键词 黄土高原地区 地震烈度 地震动 衰减关系 基岩 土层 研究进展
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渭北黄土台塬区水库水下岸坡稳定形态预测模型研究
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作者 高德彬 张昊 +3 位作者 马学通 李同录 李常虎 李启鹏 《中国农村水利水电》 北大核心 2024年第3期152-159,共8页
黄土地区水库塌岸预测仍以卡丘金法等经验图解法为主,此类方法预测结果的准确性取决于对岸坡剖面形态的准确描述。为了提高黄土地区水库塌岸宽度预测的准确性,选取渭北黄土台塬区选择典型水库进行现场调查,对原河道岸坡形态与蓄水后岸... 黄土地区水库塌岸预测仍以卡丘金法等经验图解法为主,此类方法预测结果的准确性取决于对岸坡剖面形态的准确描述。为了提高黄土地区水库塌岸宽度预测的准确性,选取渭北黄土台塬区选择典型水库进行现场调查,对原河道岸坡形态与蓄水后岸坡形态进行对比分析,在此基础上建立了水下岸坡形态预测模型。结果表明,渭北黄土台塬区水库岸坡塌岸稳定后,水上岸坡呈直立状,高度可达30 m以上,水下岸坡呈曲线形,受水深和岸坡高度共同影响,塌落物可能露出水面。在此基础上基于对数螺线方程建立了水下岸坡形态预测模型,并与经典图解法所用直线型岸坡进行对比,误差分析结果表明采用对数螺线方程进行水下岸坡形态预测时堆积体积误差为4.50%~39.70%,均值为12.64%,而直线型岸坡的预测误差为25.75%~124.69%,均值为75.69%。即采用对数螺线方程可以更好的测水下岸坡形态及水下堆积量。相关研究成果对黄土台塬区水库塌岸预测方法的改进,以及黄河流域的渭北黄土台塬区的环境保护与高质量发展具有实际意义。 展开更多
关键词 渭北黄土台塬 塌岸预测 水下岸坡稳定形态 对数螺线方程 塌岸特征
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The effect of land use structure on the distribution of soil nutrients in the hilly area of the Loess Plateau,China 被引量:32
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作者 Bojie Fu Keming Ma +1 位作者 Huafeng Zhou Liding Chen 《Chinese Science Bulletin》 SCIE EI CAS 1999年第8期732-736,共5页
The irrational land use is one of the main reasons for the soil erosion and nutrient loss in the loess hilly area of China. In this project, 4 types of typical land use structure of sustain ment for about 15 years in ... The irrational land use is one of the main reasons for the soil erosion and nutrient loss in the loess hilly area of China. In this project, 4 types of typical land use structure of sustain ment for about 15 years in the loess hill slope are selected to study the effect of land use structure on the distribution of soil nutrients. From hill bottom to hill top, the patterns of land use types are:, grassland-slope farmland-forest, slope farmland-grassland-forest, terrace-grassland-forest and slope farmland-forest-grassland. By measuring the contents of the total N, total P, available N, available P and organic matter of soils, the results show that the land use structure types of slope farmland-grassland-forest and terrace-grassland-forest have a better capacity to maintain the soil nutrients. 展开更多
关键词 HILLY area loess plateau land use structure SOIL NUTRIENT SOIL erosion.
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Slope spectrum critical area and its spatial variation in the Loess Plateau of China 被引量:20
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作者 TANG Guoan SONG Xiaodong +2 位作者 LI Fayuan ZHANG Yong XION-GLiyang 《Journal of Geographical Sciences》 SCIE CSCD 2015年第12期1452-1466,共15页
Slope spectrum has been proved to be a significant methodology in revealing geomorphological features in the study of Chinese loess terrain. The determination of critical areas in deriving slope spectra is an indispen... Slope spectrum has been proved to be a significant methodology in revealing geomorphological features in the study of Chinese loess terrain. The determination of critical areas in deriving slope spectra is an indispensable task. Along with the increase in the size of the study area, the derived spectra are becoming more and more alike, such that their dif- ferences can be ignored in favor of a standard. Subsequently, the test size is defined as the Slope Spectrum Critical Area (SSCA). SSCA is not only the foundation of the slope spectrum calculation but also, to some extent, a reflection of geomorphological development of loess relief. High resolution DEMs are important in extracting the slope spectrum. A set of 48 DEMs with different landform areas of the Loess Plateau in northern Shaanxi province was selected for the experiment. The spatial distribution of SSCA is investigated with a geo-statistical analysis method, resulting in values ranging from 6.18 km^2 to 35.1 km^2. Primary experimental results show that the spatial distribution of SSCA is correlated with the spatial distribution of the soil erosion intensity, to a certain extent reflecting the terrain complexity. The critical area of the slope spectrum presents a spatial variation trend of weak-strong-weak from north to south. Four terrain parameters, gully density, slope skewness, terrain driving force (Td) and slope of slope (SOS), were chosen as indicators. There exists a good exponential function relationship between SSCA and gully density, terrain driving force (Td) and SOS and a loga- rithmic function relationship between SSCA and slope skewness. Slope skewness increases, and gully density, terrain driving force and SOS decrease with increasing SSCA. SSCA can be utilized as a discriminating factor to identify loess landforms, in that spatial distributions of SSCA and the evolution of loess landforms are correlative. Following the evolution of a loess landform from tableland to gully-hilly region, this also proves that SSCA can represent the development degree of local landforms. The critical stable regions of the Loess Plateau represent the degree of development of loess landforms. Its chief significance is that the per- ception of stable areas can be used to determine the minimal geographical unit. 展开更多
关键词 digital elevation model slope spectrum critical area spatial variation independent geomorphological unit loess plateau
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从土壤保持角度探索全国生态桑产业发展布局
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作者 王谢 赵爱春 +1 位作者 陈冠陶 张建华 《蚕学通讯》 2024年第2期61-67,共7页
桑树具有十分强大的土壤保护功能。本文基于全国生态功能区划,瞄准生态桑在土壤保持生态系统服务功能中持续作用的重大科学问题,考量了桑树在各类生态重点区域的定位和价值实现途径。通过分析各生态区域蚕桑产业发展的基础状况,确定了... 桑树具有十分强大的土壤保护功能。本文基于全国生态功能区划,瞄准生态桑在土壤保持生态系统服务功能中持续作用的重大科学问题,考量了桑树在各类生态重点区域的定位和价值实现途径。通过分析各生态区域蚕桑产业发展的基础状况,确定了西南喀斯特区、川滇干热河谷区、三峡库区、黄土高原区、鲁中山区和昆仑山区等6个桑树土壤保持核心服务区。针对上述6个桑树土壤保持核心服务区的产业生态特征,分别提出了保墒增碳、护土保水、保土降污、屯水治沙、肥土增碳和防风固沙的土壤管理技术,并推荐了广西宜州、四川盐边、重庆巫溪、陕西榆林、山东烟台和新疆和田等6个技术先行示范区。 展开更多
关键词 生态桑 土壤保持 喀斯特地区 黄土高原 干热河谷
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自然和人为干扰因素对黄土高原生态环境质量变化的影响
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作者 牛鸿波 田少国 +8 位作者 祖鹏举 曹满红 曲少东 董起广 李冰倩 姜泽玉 毕银丽 刘英 岳辉 《煤炭工程》 北大核心 2024年第3期157-166,共10页
为了识别自然和人为干扰因素对黄土高原生态环境质量变化的影响,以黄土高原为研究区,基于GEE平台和MODIS数据获取区域内2003-2022年的遥感生态指数(RSEI),利用随机森林识别自然因素和人为干扰因素对RSEI变化的驱动作用。结果表明:近20年... 为了识别自然和人为干扰因素对黄土高原生态环境质量变化的影响,以黄土高原为研究区,基于GEE平台和MODIS数据获取区域内2003-2022年的遥感生态指数(RSEI),利用随机森林识别自然因素和人为干扰因素对RSEI变化的驱动作用。结果表明:近20年内,(1)黄土高原的生态环境质量轻微改善,以0.002/a的速率增加,且生态环境质量空间分布总体呈由东南向西北递减的趋势,空间分布异质性较大,整体表现为良;蒙陕矿区和山西矿区大部分区域,以及黄陇矿区和宁东矿区的生态环境质量改善较为明显,占比分别为40.5%、25.7%、14.6%和19.9%,山西矿区和豫西矿区部分区域退化较为明显,占比分别为5.4%和34.3%。(2)黄土高原气温降低和升高区域分别占比46.3%和13.3%,而92.7%区域的降水不变;63.1%的土壤水、58.4%的地表径流和96.6%区域的地下水储量增加;98.5%区域的GDP增加,62.7%和20.9%区域的人口增加和降低,近70%的土地利用类型基本不变,其余区域的地物类型相互转换。(3)黄土高原RSEI改善区域主要受地表径流(占比39.8%)、地下水储量(15.7%)、GDP(13.4%)和气温(12.4%)的影响,退化区域主要受GDP(22.2%)、地表径流(21.3%)、地下水储量(16.4%)、气温(12.5%)和夜间灯光(10.5%)的影响;其次,RSEI改善的煤炭基地主要受地表径流和GDP的影响,退化的煤炭基地受GDP、夜间灯光、地下水储量和气温因素主导。综上所述,近20年内黄土高原生态环境得到改善,生态环境质量变化主要受地下水储量、地表径流、气温、夜间灯光、人口和GDP的影响。 展开更多
关键词 黄土高原 生态环境 煤矿区 随机森林 驱动因子
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黄土高原半干旱雨养农业区冬小麦气候适宜度评价——以通渭县为例
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作者 焦润安 李旭华 +4 位作者 齐月 雷俊 苟志文 臧亚军 薛潇 《中国农学通报》 2024年第17期73-80,共8页
气候适宜度可以表征气候条件对作物生长发育的影响程度。利用黄土高原半干旱区通渭县近40 a气象资料和农业气象观测资料,基于模糊数学方法,根据冬小麦各发育时段对温度、水分、光照的需求,对黄土高原半干旱雨养农业区冬小麦全生育期气... 气候适宜度可以表征气候条件对作物生长发育的影响程度。利用黄土高原半干旱区通渭县近40 a气象资料和农业气象观测资料,基于模糊数学方法,根据冬小麦各发育时段对温度、水分、光照的需求,对黄土高原半干旱雨养农业区冬小麦全生育期气候适宜度进行评价。结果表明:通渭县近40 a冬小麦全生育期温度适宜度为0.58,停止生长—返青期的温度适宜度最高,达0.95,三叶期—停止生长的温度适宜度低,仅为-0.42,年际间差异小,全生育期温度适宜度以0.019/10 a的速率上升;水分适宜度为0.46,乳熟期—成熟期的水分适宜度最高,为0.66,其次为返青期—拔节期,为0.63,年际间差异大,全生育期水分适宜度以0.017/10 a的速率上升;光照适宜度为0.62,三叶期—停止生长和返青期—拔节期的光照适宜度最高,为0.68,乳熟期—成熟期最低,为0.51,全生育期光照适宜度以0.011/10 a的速率上升;综合适宜度为0.54,返青期—拔节期的综合适宜度最高,为0.70,三叶期—停止生长最低,为-0.36,全生育期综合适宜度以0.014/10 a的速率上升。冬小麦产量与抽穗期—乳熟期温度适宜度、乳熟期—成熟期水分适宜度、乳熟期—成熟期综合适宜度呈显著相关。气候适宜度能够较准确地反映出黄土高原半干旱雨养农业区冬小麦生育期内气象条件的优劣变化。 展开更多
关键词 黄土高原半干旱区 冬小麦 气候适宜度 评价指标
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