Liupan Mountains are situated in the south of Ningxia Hui Autonomous Region and east of Gansu Province.This area is rich in forests and vegetation.After field investigation,literature review and specimen identificatio...Liupan Mountains are situated in the south of Ningxia Hui Autonomous Region and east of Gansu Province.This area is rich in forests and vegetation.After field investigation,literature review and specimen identification,the plant resources and diversity of Liupan Mountains were studied by the 4th Shenyang Pharmaceutical University Chinese Medicine Resources Scientific Expedition Team.There were 161 species of vascular plants belonging to 60 families and 119 genera collected from July to August 2010 in this area.Among them,the dominant families are Campanulaceae,Ranunculaceae,Orobanchaceae,Asparagaceae,Fabaceae,Rosaceae and Asteraceae,with 6,7,8,8,10,10,and 22 species,respectively.Although representing only 11.7%of the total number of families,these families had a species occupancy rate of over 44.1%.At the genus level,Pedicularis is the most dominant genus with 6 species,while 92 genera contain only 1 species,accounting for 77.3%of the total number of genera.In a word,our research has updated the plant resources and diversity in Liupan Mountains.Furthermore,by providing practical and meaningful suggestions for strengthening the protection and utilization of plant resources in Liupan Mountains,our research is of great significance for maintaining the diverse ecosystem in this area.展开更多
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
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
China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragil...China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragility and risk susceptibility have increased the risk of returning to ecological poverty.In this paper,the Liupan Mountain Region of China was used as a case study,and the counties were used as the scale to reveal the spatiotempora differentiation and influcing factors of the risk of returning to poverty in study area.The indicator data for returning to ecological poverty from 2011-2020 were collected and summarized in three dimensions:ecological,economic and social.The autoregressive integrated moving average model(ARIMA)time series and exponential smoothing method(ES)were used to predict the multidimensional indicators of returning to ecological poverty for 61 counties(districts)in the Liupan Mountain Region for 2021-2030.The back propagation neural network(BPNN)and geographic information system(GIS)were used to generate the spatial distribution and time variation for the index of the risk of returning to ecological poverty(RREP index).The results show that 1)ecological factors were the main factors in the risk of returning to ecological poverty in Liupan Mountain Region.2)The RREP index for the 61 counties(districts)exhibited a downward trend from 2021-2030.The RREP index declined more in medium-and high-risk areas than in low-risk areas.From 2021 to 2025,the RREP index exhibited a slight downward trend.From 2026 to2030,the RREP index was expected to decline faster,especially from 2029-2030.3)Based on the RREP index,it can be roughly divided into three types,namely,the high-risk areas,the medium-risk areas,and the low-risk areas.The natural resource conditions in lowrisk areas of returning to ecological poverty,were better than those in medium-and high-risk areas.展开更多
A portable broadband seismic array was deployed from the northeast Tibetan Plateau to the southwest Ordos block,China.The seismic structure of the crust and uppermost mantle of the Liupanshan area is obtained using re...A portable broadband seismic array was deployed from the northeast Tibetan Plateau to the southwest Ordos block,China.The seismic structure of the crust and uppermost mantle of the Liupanshan area is obtained using receiver function analysis of teleseismic body waves.The crustal thickness and Poisson's ratios are estimated by stacking the weighted amplitudes of receiver functions.Our results reveal complex seismic phases in the Liupanshan area,implying intense deformation at the boundary between the Tibetan Plateau and the Ordos block.The average crustal thickness is 51.5 km in the northeast Tibetan Plateau,53.5 km in the Liupan Mountain and 50 km in the southwest Ordos block,resulting in a concave Moho beneath the Liupan Mountain.The Poisson's ratio of the Liupanshan area varies between 0.27-0.29,higher than the value of 0.25-0.26 to the east and west of the Liupan Mountain,suggesting partial melting in the lower crust.The variance in Poisson's ratio across the Liupan Mountain indicates notable changes in the crustal composition and mechanical properties,which may be formed by the northeastward flow of the Tibetan lower crust during the India-Eurasia collision.展开更多
The Liupan Mountains are located in the southern Ningxia Hui Autonomous Region of China,that forms an important divide between landforms and biogeographic regions.The populated part of the Liupan Mountain Region has s...The Liupan Mountains are located in the southern Ningxia Hui Autonomous Region of China,that forms an important divide between landforms and biogeographic regions.The populated part of the Liupan Mountain Region has suffered tremendous ecological damage over time due to population pressure,excessive demand and inappropriate use of agricultural land resources.To present the relationship between land use/cover change and spatio-temporal variation of soil erosion,data sets of land use between the late 1980s and 2000 were obtained from Landsat Thematic Mapper(TM)imagery,and spatial models were used to characterize landscape and soil erosion conditions.Also,soil erosion in response to land use and land cover change were quantified and analyzed using data from geographical information systems and remote sensing.Soil erosion by water was the dominant mode of soil loss,while soil erosion by wind was only present on a relatively small area.The degree of soil erosion was classified into five severity classes:slight,light,moderate,severe,and very severe.Soil erosion in the Liupan Mountain Region increased between the late 1980s and 2000,both in terms of acreage and severity.Moderate,severe,and very severe eroded areas accounted for 54.86%of the total land area.The lightly eroded area decreased,while the moderately eroded area increased by 368817 ha(22%)followed by severe erosion with 146552 ha(8.8%),and very severe erosion by 97067.6 ha(5.8%).Soil loss on sloping cropland increased with slope gradients.About 90%of the cropland was located on slopes less than 15°.Most of the increase in soil erosion on cropland was due to conversion of steep slopes to cropland and degradation of grassland and increased activities.Soil erosion was severe on grassland with a moderate or low grass cover and on dry land.Human activities,cultivation on steep slopes,and overgrazing of pastures were the main reasons for the increase in erosion severity.展开更多
文摘Liupan Mountains are situated in the south of Ningxia Hui Autonomous Region and east of Gansu Province.This area is rich in forests and vegetation.After field investigation,literature review and specimen identification,the plant resources and diversity of Liupan Mountains were studied by the 4th Shenyang Pharmaceutical University Chinese Medicine Resources Scientific Expedition Team.There were 161 species of vascular plants belonging to 60 families and 119 genera collected from July to August 2010 in this area.Among them,the dominant families are Campanulaceae,Ranunculaceae,Orobanchaceae,Asparagaceae,Fabaceae,Rosaceae and Asteraceae,with 6,7,8,8,10,10,and 22 species,respectively.Although representing only 11.7%of the total number of families,these families had a species occupancy rate of over 44.1%.At the genus level,Pedicularis is the most dominant genus with 6 species,while 92 genera contain only 1 species,accounting for 77.3%of the total number of genera.In a word,our research has updated the plant resources and diversity in Liupan Mountains.Furthermore,by providing practical and meaningful suggestions for strengthening the protection and utilization of plant resources in Liupan Mountains,our research is of great significance for maintaining the diverse ecosystem in this area.
基金Under the auspices of the National Key Science and Technology Support Program of China (No. 2006BCA01A07-2)National Natural Science Foundation of China (No. 40671153)+1 种基金Hunan Land Resource Bureau Program (No. 2007-15)Hunan Educa-tion Bureau Program (No. 08C348)
文摘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.
基金supported by the National Natural Science Foundation of China(Grant No.42488201)the Strategy Priority Research Program(Category B)of Chinese Academy of Sciences(Grant No.XDB0710000)。
文摘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.
基金Under the auspices of National Natural Science Foundation of China(No.42071230)。
文摘China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragility and risk susceptibility have increased the risk of returning to ecological poverty.In this paper,the Liupan Mountain Region of China was used as a case study,and the counties were used as the scale to reveal the spatiotempora differentiation and influcing factors of the risk of returning to poverty in study area.The indicator data for returning to ecological poverty from 2011-2020 were collected and summarized in three dimensions:ecological,economic and social.The autoregressive integrated moving average model(ARIMA)time series and exponential smoothing method(ES)were used to predict the multidimensional indicators of returning to ecological poverty for 61 counties(districts)in the Liupan Mountain Region for 2021-2030.The back propagation neural network(BPNN)and geographic information system(GIS)were used to generate the spatial distribution and time variation for the index of the risk of returning to ecological poverty(RREP index).The results show that 1)ecological factors were the main factors in the risk of returning to ecological poverty in Liupan Mountain Region.2)The RREP index for the 61 counties(districts)exhibited a downward trend from 2021-2030.The RREP index declined more in medium-and high-risk areas than in low-risk areas.From 2021 to 2025,the RREP index exhibited a slight downward trend.From 2026 to2030,the RREP index was expected to decline faster,especially from 2029-2030.3)Based on the RREP index,it can be roughly divided into three types,namely,the high-risk areas,the medium-risk areas,and the low-risk areas.The natural resource conditions in lowrisk areas of returning to ecological poverty,were better than those in medium-and high-risk areas.
基金Supperted by the National Basic Research Program of China(Grant No.2003CB214607)the National Natural Science Foundation of China(Grant No.40574015)SRFDP(Grant No.20050284040)
文摘A portable broadband seismic array was deployed from the northeast Tibetan Plateau to the southwest Ordos block,China.The seismic structure of the crust and uppermost mantle of the Liupanshan area is obtained using receiver function analysis of teleseismic body waves.The crustal thickness and Poisson's ratios are estimated by stacking the weighted amplitudes of receiver functions.Our results reveal complex seismic phases in the Liupanshan area,implying intense deformation at the boundary between the Tibetan Plateau and the Ordos block.The average crustal thickness is 51.5 km in the northeast Tibetan Plateau,53.5 km in the Liupan Mountain and 50 km in the southwest Ordos block,resulting in a concave Moho beneath the Liupan Mountain.The Poisson's ratio of the Liupanshan area varies between 0.27-0.29,higher than the value of 0.25-0.26 to the east and west of the Liupan Mountain,suggesting partial melting in the lower crust.The variance in Poisson's ratio across the Liupan Mountain indicates notable changes in the crustal composition and mechanical properties,which may be formed by the northeastward flow of the Tibetan lower crust during the India-Eurasia collision.
基金This research was supported by program of the State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Water and Soil Conservation,Chinese Academy of Sciences and Ministry of Water Resources(No.10501-298)National Key Basic Research Program(2007CB407200)Open Research Fund of State Key Laboratory of Remote Sensing Science,Jointly Sponsored by Beijing Normal University and the Institude of Remote Sensing Applicantions of Chinese Academy of Sciences(2009KFJJ019).
文摘The Liupan Mountains are located in the southern Ningxia Hui Autonomous Region of China,that forms an important divide between landforms and biogeographic regions.The populated part of the Liupan Mountain Region has suffered tremendous ecological damage over time due to population pressure,excessive demand and inappropriate use of agricultural land resources.To present the relationship between land use/cover change and spatio-temporal variation of soil erosion,data sets of land use between the late 1980s and 2000 were obtained from Landsat Thematic Mapper(TM)imagery,and spatial models were used to characterize landscape and soil erosion conditions.Also,soil erosion in response to land use and land cover change were quantified and analyzed using data from geographical information systems and remote sensing.Soil erosion by water was the dominant mode of soil loss,while soil erosion by wind was only present on a relatively small area.The degree of soil erosion was classified into five severity classes:slight,light,moderate,severe,and very severe.Soil erosion in the Liupan Mountain Region increased between the late 1980s and 2000,both in terms of acreage and severity.Moderate,severe,and very severe eroded areas accounted for 54.86%of the total land area.The lightly eroded area decreased,while the moderately eroded area increased by 368817 ha(22%)followed by severe erosion with 146552 ha(8.8%),and very severe erosion by 97067.6 ha(5.8%).Soil loss on sloping cropland increased with slope gradients.About 90%of the cropland was located on slopes less than 15°.Most of the increase in soil erosion on cropland was due to conversion of steep slopes to cropland and degradation of grassland and increased activities.Soil erosion was severe on grassland with a moderate or low grass cover and on dry land.Human activities,cultivation on steep slopes,and overgrazing of pastures were the main reasons for the increase in erosion severity.