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Application of the improved dung beetle optimizer,muti-head attention and hybrid deep learning algorithms to groundwater depth prediction in the Ningxia area,China 被引量:1
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作者 Jiarui Cai Bo Sun +5 位作者 Huijun Wang Yi Zheng Siyu Zhou Huixin Li Yanyan Huang Peishu Zong 《Atmospheric and Oceanic Science Letters》 2025年第1期18-23,共6页
Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical models.Machine learning can effectively solve this issue and has been proven useful in th... Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical models.Machine learning can effectively solve this issue and has been proven useful in the prediction of groundwater depth in many areas.In this study,two new models are applied to the prediction of groundwater depth in the Ningxia area,China.The two models combine the improved dung beetle optimizer(DBO)algorithm with two deep learning models:The Multi-head Attention-Convolution Neural Network-Long Short Term Memory networks(MH-CNN-LSTM)and the Multi-head Attention-Convolution Neural Network-Gated Recurrent Unit(MH-CNN-GRU).The models with DBO show better prediction performance,with larger R(correlation coefficient),RPD(residual prediction deviation),and lower RMSE(root-mean-square error).Com-pared with the models with the original DBO,the R and RPD of models with the improved DBO increase by over 1.5%,and the RMSE decreases by over 1.8%,indicating better prediction results.In addition,compared with the multiple linear regression model,a traditional statistical model,deep learning models have better prediction performance. 展开更多
关键词 Groundwater depth Multi-head attention Improved dung beetle optimizer CNN-LSTM CNN-GRU ningxia
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Exploration on the Construction of Intelligent Big Data Platform of Ningxia Solar Photovoltaic Industry based on NB-IoT
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作者 Huijun Wang Weiying Chong 《Journal of Electronic Research and Application》 2025年第1期295-301,共7页
As China’s first new energy comprehensive demonstration zone,Ningxia’s solar photovoltaic(PV)industry has developed rapidly,but it still faces shortcomings in terms of intelligence and digitalization.This study focu... As China’s first new energy comprehensive demonstration zone,Ningxia’s solar photovoltaic(PV)industry has developed rapidly,but it still faces shortcomings in terms of intelligence and digitalization.This study focuses on the application and construction of an intelligent big data platform based on Narrowband Internet of Things(NB-IoT)technology within Ningxia’s solar PV industry.It explores the application trends of digital technology in the energy sector,particularly in the PV industry under the backdrop of energy reform,analyzes the technological development status of the smart energy field both domestically and internationally,and details the research methods and design components of the platform(including the photovoltaic base data platform,outdoor mobile application,remote data system,and back-office management system).The study discusses the opportunities and challenges Ningxia’s PV industry faces and proposes a construction pathway.It provides a theoretical foundation and technical support for the digital transformation of Ningxia’s PV industry,facilitating industrial upgrading and sustainable development.Although the current research is limited to the proposed design scheme,it establishes a basis for future empirical research and platform development. 展开更多
关键词 ningxia Solar photovoltaic NB-IoT Intelligent big data platform Digital transformation
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Geochronology,Geochemistry,and Sr-Nd-Hf Isotopes of the Diorite Porphyrites from the Weining Beishan Area,Ningxia Hui Autonomous Region:Constraints on Their Source and Tectonic Implications 被引量:1
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作者 Anlu Liu Lianfu Hai +5 位作者 Jinke Liu Xiaojun Zhang Haifeng Li Fengshun Zhao Guoliang Zhao Jinhe Bai 《Journal of Earth Science》 SCIE CAS CSCD 2024年第2期462-475,共14页
The Weining Beishan area of Ningxia Hui Autonomous Region is located at on the western edge of the Helanshan tectonic belt,which is a tectonic joint among Alxa Block,Ordos Block,and North Qilian orogenic belt.However,... The Weining Beishan area of Ningxia Hui Autonomous Region is located at on the western edge of the Helanshan tectonic belt,which is a tectonic joint among Alxa Block,Ordos Block,and North Qilian orogenic belt.However,the tectonic evolution of this area remains unclear due to the lack of magmatic information.This paper conducted researches on geochronology,geochemistry,and Sr-Nd-Hf isotopes of the diorite porphyrites exposed in the Weining Beishan area.The zircon U-Pb dating yields two ages of 145.0±1.1 and 146.2±1.5 Ma,and the whole-rock geochemical data indicate that the diorite porphyrites are metaluminous to weakly peraluminous and high-K calc-alkaline series.The characteristics of highly initial^(87)Sr/^(86)Sr ratios(0.70816 to 0.71047),negativeε_(Nd)(t)(−8.9 to−8.4),and negativeε_(Hf)(t)(−13.8 to−21.2)indicate that the diorite porphyrites originated from partial melting of the middle-lower ancient crust related to the North China Craton.Combined with the regional geology,we suggested that partial melting was triggered by a tectonic activity of deep faults cutting through the crust under the regional stress transformation from compressing to extension during the Late Jurassic–Early Cretaceous,which is probably related to the westward subduction of the Paleo-Pacific Plate. 展开更多
关键词 zircon U-Pb dating Sr-Nd-Hf isotopes magma source diorite porphyrite Weining Beishan area ningxia Hui Autonomous Region GEOCHRONOLOGY GEOCHEMISTRY
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Emergence of highly pathogenic avian influenza A(H5N8)clade 2.3.4.4b viruses in grebes in Inner Mongolia and Ningxia,China,in 2021 被引量:1
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作者 Qiuzi Xu Xinru Lü +17 位作者 Yi Li Hua Luo Zhen Zhang Xiang Li Rongxiu Qin Qing An Fengyi Qu Zhenliang Zhao Chengbo Zhang Weidong Wang Yuecheng Li Yajun Wang Xiangwei Zeng Zhijun Hou Jingqiang Ren Yulong Wang Yanbing Li Hongliang Chai 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期348-353,共6页
Highly pathogenic avian influenza(HPAI)subtype H5Nx viruses have spread globally and are a major concern for poultry,wild birds,mammals,and even humans(de Vries et al.2015;Zeng et al.2022).The hemagglutinin(HA)genes o... Highly pathogenic avian influenza(HPAI)subtype H5Nx viruses have spread globally and are a major concern for poultry,wild birds,mammals,and even humans(de Vries et al.2015;Zeng et al.2022).The hemagglutinin(HA)genes of H5 subtype viruses have evolved into multiple clades and some of these clades have been further divided into subclades(Cui et al.2022).Clade 2.3.4.4H5N8 HPAI viruses(HPAIVs)have caused several waves of disease outbreaks in wild birds and domestic poultry(Wang et al.2022). 展开更多
关键词 POULTRY ningxia INFLUENZA
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The Amazing Ningxia Walking on the Ancient Silk Road
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《China & The World Cultural Exchange》 2024年第12期42-47,共6页
Located in the middle and upper reaches of the Yellow River in China,Ningxia is one of the origins of the Chinese civilization,an important node on the ancient Silk Road,and a transmission station and distribution cen... Located in the middle and upper reaches of the Yellow River in China,Ningxia is one of the origins of the Chinese civilization,an important node on the ancient Silk Road,and a transmission station and distribution center of the Oriental and Occidental cultures.The diverse and rich terrains have created the unique and colorful natural scenery of Ningxia,which is known as"China’s Miniature Bonsai of Tourism"and has been known as"Jiangnan Beyond the Great Wair since ancient times.The magnificent desert scenery,the ancient Yellow River civilization,the mysterious ancient charm of the Western Xia Regime,the remote Silk Road,with the reputation of"the World Heritage Irrigation Structures","the Global Wine Tourism Destination","the Great Wall Museum","the Capital of Gojl Berry in the World","the Capital of Wine in the World"and"the Hometown of Tan Sheep in China",have made Ningxia,a great post station and an important commercial port on the Silk Road in history,a unique tourist destination in western China.Ningxia has been rated as one of the 46 best places to visit in the world by The New York Times. 展开更多
关键词 ningxia ANCIENT BERRY
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Ningxia Hometown of Stars·Purple Impression
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《China & The World Cultural Exchange》 2024年第12期48-48,共1页
To promote and showcase local high-quality cultural and tourism resources,the Network of International Culturalink Entities,in collaboration with the Department of Culture and Tourism of Ningxia Hui Autonomous Region,... To promote and showcase local high-quality cultural and tourism resources,the Network of International Culturalink Entities,in collaboration with the Department of Culture and Tourism of Ningxia Hui Autonomous Region,has meticulously planned and produced the cultural tourism promotional video/V/ngx/a themed on"Hometown of Stars·Purple Impression".We invite five KOLs(Key Opinion Leaders)from different countries,including cultural exchange ambassador Alla(UK),magazine editor and food blogger Sophie(USA),photography enthusiast Olmo(Spain),self-media blogger Piotr(Poland),and photography blogger Alexander(South Africa)to immerse themselves in the unique cultural and tourism resources of Ningxia. 展开更多
关键词 ningxia EDITOR PROMOTION
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Impacts of Land Use Change on Ecosystem Service Value in Yanchi County of Ningxia 被引量:3
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作者 杨越 孙保平 +3 位作者 哈斯 杜会石 赵岩 赵瑞 《Agricultural Science & Technology》 CAS 2013年第11期1687-1692,共6页
Based on TM image data in 1989, 1995, 1999, 2003, 2006 and 2009 of Yanchi County of Ningxia, the land use date of Yanchi County in each year were extracted supported by RS and GIS technology, and used to analyze the d... Based on TM image data in 1989, 1995, 1999, 2003, 2006 and 2009 of Yanchi County of Ningxia, the land use date of Yanchi County in each year were extracted supported by RS and GIS technology, and used to analyze the dynamic change of land use. The land use data were studied for estimating the change of ecosystem services value caused by the land use change of Yanchi County, using the evaluation method of China terrestrial ecosystem services value. The results showed that the changes of land use were obvious during 1989 to 2009. The area of woodland and construction land had an increasing tendency; grassland area changed from decreasing to increasing, which was in contrary to farmland and un-used land areas (from increasing to decreasing); water area fluctuated slightly. The ecosystem services value of Yanchi County had an increasing tendency during 1989 to 1995, because the increasing woodland area had took the major role in raising the total ecosystem services value. The grassland accounted for a large proportion of the total ecosystem service value of Yanchi County, with its contribution rate from 49.8% to 60.4%. And the composition of the ecosystem services value of Yanchi County happened benign change for the increasing contribution rate of woodland. The ecosystem services value sensitivity index of each land use type was less than 1, indicating that the ecosystem services value of Yanchi County lacks flexibility on its service value index, and the research results are reliable. 展开更多
关键词 Ecosystem services value Land use change Yanchi County of ningxia
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Prediction of Maize Yield and Its Component Factors in Yellow River Irrigation Area of Ningxia under Climate Change 被引量:1
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作者 刘玉兰 任玉 +1 位作者 王迎春 郭晓雷 《Agricultural Science & Technology》 CAS 2011年第5期699-701,736,共4页
[Objective] The aim was to quantitatively predict the variation trend of maize yield in Yellow River irrigation area of Ningxia under future climate change scenarios.[Method] Based on the data of daily temperature,pre... [Objective] The aim was to quantitatively predict the variation trend of maize yield in Yellow River irrigation area of Ningxia under future climate change scenarios.[Method] Based on the data of daily temperature,precipitation and radiation in 25 km × 25 km grid in Ningxia from 2010 to 2100 obtained by regional climate model,maize yield in Yellow River irrigation area of Ningxia in the 21st century was studied by means of corrected CERES-Maize model.[Result] With climate warming,maize yield in Yellow River irrigation area of Ningxia in 2020s and 2050s showed increase trend compared with base years(average in 1961-1990)when current adaptive maize variety and optimum production management measures were adopted,while maize yield went down in 2080s with the further increase of temperature.The grain number per spike and spike grain weight as the yield components of maize also showed the same trend with maize yield.In 2020s and 2050s,the increase of maize yield under B2 scenario was higher than that under A2 scenario,while the decrease of maize yield under B2 scenario was lower than that under A2 scenario in 2080s.[Conclusion] With the increase of temperature,maize yield in Yellow River irrigation area of Ningxia went up firstly and then went down. 展开更多
关键词 Yellow River irrigation area of ningxia Climate change MAIZE
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Analysis on Temporal and Spatial Characteristic and Variation of Precipitation in Ningxia Hui Autonomous Region 被引量:1
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作者 陈海波 严华生 +2 位作者 苏发奋 杨继祖 鲁统亮 《Meteorological and Environmental Research》 CAS 2010年第10期47-52,57,共7页
Based on seasonal and annual observed precipitation data at 19 meteorological stations in Ningxia Hui Autonomous Region,the temporal and spatial distribution characteristic is analyzed by EOF method.And spatial charac... Based on seasonal and annual observed precipitation data at 19 meteorological stations in Ningxia Hui Autonomous Region,the temporal and spatial distribution characteristic is analyzed by EOF method.And spatial characteristics and temporal changes trends of EOF of seasonal and annual precipitation have been showed.The main period and sudden changes point of EOF of annual precipitation have been studied by Mann-Kendall and spectrum analysis method. 展开更多
关键词 PRECIPITATION Temporal-Spatial Distribution VARIATION ningxia China
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Sustainability Analysis of Cropland Use in Cropping-Pastoral Ecotone before and after the Grain-for-Green Policy:A Case Study from Yanchi County in Ningxia 被引量:1
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作者 王秀红 申建秀 《Agricultural Science & Technology》 CAS 2013年第1期88-93,共6页
[Objective] This study aimed to analyze the sustainability of cropland use in cropping-pastoral ecotone before and after the Grain-for-Green Policy. [Method] Using Yanchi County in Ningxia Hui Autonomous Region as a c... [Objective] This study aimed to analyze the sustainability of cropland use in cropping-pastoral ecotone before and after the Grain-for-Green Policy. [Method] Using Yanchi County in Ningxia Hui Autonomous Region as a case study area, this investigation used the annual transfer rate of land use types, cropland suitability and emergy analysis to examine the major pressures affecting the sustainable use of cropland before and after the Grain-for-Green Policy. [Result] The expansion of con- struction land onto cropland was significant; the annual cropland area was still larger than the land area suitable for cropping after the policy; agrochemical inputs used for crop production gradually increased and unit crop outputs required more agro- chemical inputs. Cropland use sustainability showed a fluctuating downward trend. [Conclusion] The results imply that the protection of high quality cropland, further im- plementation of the policy and control of agrochemical inputs according to precipita- tion are the main measures needed for sustainable cropland use in cropping-pastoral ecotone. 展开更多
关键词 Cropland use sustainability Construction land Agrochemicals Emergy analysis Yanchi County in ningxia
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Analysis of Drought Changes and Drought Mitigation in Xiji County of Ningxia
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作者 孙俊 张学艺 +2 位作者 李剑萍 齐旭峰 魏广泱 《Agricultural Science & Technology》 CAS 2011年第11期1682-1686,共5页
[Objective] The aim was to study the characteristics of the changes of extreme weather climate incidents such as severe drought in northwest and rainstorm in Xiji County of Ningxia. [Method] Precipitation anomaly perc... [Objective] The aim was to study the characteristics of the changes of extreme weather climate incidents such as severe drought in northwest and rainstorm in Xiji County of Ningxia. [Method] Precipitation anomaly percentage was applied to divide drought level and for statistics analysis. Seasonal index, linear tendency, and 5-years gliding average were used to reflect the trend of drought changes. The circulation wave of temporal sequence used polynomial expression to simulate the interannual variation scale. The positive part of the polynomial expression used bar chart to simulate interannual variation scale. [Result] The index of drought season from November to June was large. The general trend of annual drought was increasing. The drought of interannual scale was most serious around 1977, about 15 and 20 years. The drought in recent years went up. The general situation of drought, interannual scale and changes of interannual scales from March to May and from September to October were discussed. Based on the weather at 500 hPa, the first rain in Xiji and the drought-turning-into-rain situation were classified. [Conclusion]These may provide reference value to the prevention and mitigation of drought. 展开更多
关键词 Drought in Xiji of ningxia Development tendency Different scales Drought mitigation situation
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Research on the Green Planning in Rural Settlements of Hui Nationality in Central Ningxia
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作者 李晓玲 《Journal of Landscape Research》 2010年第3期1-4,共4页
Targeted at the residence status in rural settlements of Hui people in central Ningxia Hui Nationality Autonomous Region, this research revealed that the construction of new countryside and the transformation of old c... Targeted at the residence status in rural settlements of Hui people in central Ningxia Hui Nationality Autonomous Region, this research revealed that the construction of new countryside and the transformation of old countryside all have to be on the basis of present topography, landform, environment, social-economic level, education, religion, customs, living habits and so on. The primary goal of this research was to find a method of ecology, low energy consumption and sustainable development to bring the green planning implementation strategies, to provide guidance for sustainable planning in the rural settlements of Hui Nationality in central Ningxia. 展开更多
关键词 The rural areas of central ningxia Settlements of Hui Nationality Green planning Sustainable development
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Historical Changes of Ningxia Natural Disasters and Its Reason Analysis 被引量:1
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作者 丁建军 冯建民 +1 位作者 梁旭 陈晓娟 《Meteorological and Environmental Research》 CAS 2010年第12期67-70,81,共5页
A quantitative model is built and the historical variation of natural disasters is analyzed in this paper,by using materials as affected area(damaged area),affected population(dead and injured),casualty of livestock,c... A quantitative model is built and the historical variation of natural disasters is analyzed in this paper,by using materials as affected area(damaged area),affected population(dead and injured),casualty of livestock,collapsed houses(damaged houses),decrease of crops yield,economic loss(direct and indirect) and price index over the same period of Ningxia natural disasters(include drought,flood,gale and hail,frost,pest disasters and other disasters) during 1978-2007,and applying gray correlation analysis method.The long-term changes trend of natural disasters is analyzed by the application of the least squares method for linear trend,and the oscillation period is analyzed by using the maximum entropy statistical method.It is found that natural disasters have basically 2 to 3 years of variation period either in the whole region or in the individual regions;from the mid 1980s to the late 1990s,Ningxia is in an oscillation period with disasters attacked frequently in decadal and interannual scale under the background of climate;the increase of damage intensity of natural disasters slow down and tends to decrease since 2000. 展开更多
关键词 ningxia Natural disasters Historical changes Reason analysis China
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Seasonal changes in the water-use strategies of three herbaceous species in a native desert steppe of Ningxia,China 被引量:8
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作者 HU Haiying ZHU Lin +2 位作者 LI Huixia XU Dongmei XIE Yingzhong 《Journal of Arid Land》 SCIE CSCD 2021年第2期109-122,共14页
Frequent periods of drought conditions are known to limit plant performance,primary production,and ecosystem stability in arid and semi-arid desert steppe environments.Plants often avoid competition by shifting their ... Frequent periods of drought conditions are known to limit plant performance,primary production,and ecosystem stability in arid and semi-arid desert steppe environments.Plants often avoid competition by shifting their water use seasonally,which affects the water-use patterns of dominant species as well as the composition and structure of plant communities.However,the water-use strategies of dominant herbaceous species,which grow under natural field conditions in the desert steppe region of Ningxia Hui Autonomous Region,China,are poorly known.Here,we explored the possible sources of water uptake and water-use efficiency(WUE)of three dominant herbaceous plant species(Stipa breviflora,Agropyron mongolicum,and Glycyrrhiza uralensis)in a native desert steppe in the semi-arid area of Ningxia through an analysis of multiple parameters,including(1)the stable isotopic oxygen and hydrogen(δ18O andδ2H)compositions of precipitation,soil water,and stem water,(2)the carbon isotope(13C)composition of leaves,and(3)the soil water contents,based on field sampling across varying water conditions from June to September,2017.Frequent small precipitation events replenished shallow soil water,whereas large events only percolated down to the deep soil layers.Changes in soil water availability affected the water-use patterns of plants.Generally,during light precipitation periods,the deep root system of G.uralensis accessed deeper(>80 cm)soil water,whereas S.breviflora and A.mongolicum,which only have shallow roots,primarily absorbed water from the shallow and middle soil layers.As precipitation increased,all three plant species primarily obtained water from the shallow soil layers.Variation in soil water uptake between the dry and wet seasons enabled plants to make better use of existing satoil water.In addition,theδ13C values of G.uralensis and S.breviflora were higher than those of A.mongolicum.Theδ13C values of the three plant species were significantly negatively correlated with soil water content.Therefore,G.uralensis and S.breviflora maintained a higher WUE through their conservative and water-saving strategies across the entire growing season.In contrast,A.mongolicum,with a relatively low WUE in the wet season but a high WUE in the dry season,exhibited a more flexible water-use strategy.The different water-use strategies of these dominant plant species demonstrated the mechanisms by which plant communities can respond to drought. 展开更多
关键词 SOIL ningxia SHALLOW
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Response of Artificial Grassland Carbon Stock to Management in Mountain Region of Southern Ningxia, China 被引量:7
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作者 TANG Long DANG Xiaohu +2 位作者 LIU Guobin SHAO Chuanke XUE Sha 《Chinese Geographical Science》 SCIE CSCD 2014年第4期436-443,共8页
Grassland is a major carbon sink in the terrestrial ecosystem. The dynamics of grassland carbon stock profoundly influence the global carbon cycle. In the published literatures so far, however, there are limited studi... Grassland is a major carbon sink in the terrestrial ecosystem. The dynamics of grassland carbon stock profoundly influence the global carbon cycle. In the published literatures so far, however, there are limited studies on the long-term dynamics and influential factors of grassland carbon stock, including soil organic carbon. In this study, spatial-temporal substitution method was applied to explore the characteristics of Medicago sativa L. (alfalfa) grassland biomass carbon and soil organic carbon density (SOCD) in a loess hilly region with different growing years and management patterns. The results demonstrated that alfalfa was the mono-dominant community during the cutting period (viz. 0-10 year). Community succession began after the abandonment of alfalfa grassland and then the important value of alfalfa in the community declined. The artificial alfalfa community abandoned for 30 years was replaced by the S. bungeana community. Accordingly, the biomass carbon density of the clipped alfalfa showed a significant increase over the time during 0-10 year. During 0-30 year, the SOCD from 0-100 cm of the soil layer of all 5 management patterns increased over time with a range between 5.300 ± 0.981 kg/m2 and 12.578 ± 0.863 kg/m2. The sloping croplands had the lowest SOCD at 5.300 ± 0.981 kg/m2 which was quite different from the abandoned grasslands growing for 30 years which exhibited the highest SOCD with 12.578 ± 0.863 kg/m2. The ecosystem carbon density of the grassland clipped for 2 years increased 0.1 kg/m2 compared with the sloping cropland, while that of the grassland clipped for 10 years substantially increased to 10.30 ± 1.26 kg/m2. Moreover, the ecosystem carbon density for abandoned grassland became 12.62± 0.50 kg/m2 at 30 years. The carbon density of the grassland undisturbed for l0 years was similar to that of the sloping cropland and the grassland clipped for 2 years. Different management patterns imposed great different effects on the accumulation of biomass carbon on artificial grasslands, whereas the ecosystem carbon density of the grassland showed a slight increase from the clipping to abandonment of grassland in general. 展开更多
关键词 artificial Medicago sativa L. (alfalfa) grassland clipped grassland abandoned grassland carbon sink carbon density mountain region southern ningxia
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Innovative trend analysis of annual and seasonal precipitation in Ningxia,China 被引量:5
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作者 YANG Huiling XIAO Hui +2 位作者 GUO Chunwei SUN Yue GAO Ruina 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第4期308-315,共8页
Based on daily rainfall data from 26 station records,spatial and temporal variations in annual and seasonal precipitation of different rainfall intensities from 1961 to 2018 in Ningxia,China are investigated using the... Based on daily rainfall data from 26 station records,spatial and temporal variations in annual and seasonal precipitation of different rainfall intensities from 1961 to 2018 in Ningxia,China are investigated using the innovative trend analysis(ITA)method.The results show that annual precipitation increases on the northern plain but decreases in the southern mountainous area.The increase in regional annual precipitation is mainly due to an increase in weak precipitation,while the decrease in regional annual rainfall is a result of a reduction in heavy precipitation.Lowintensity precipitation shows an upward trend,while high-intensity precipitation shows a downward trend.The variation trend of extreme precipitation is more obvious.The contributions of different types of extreme precipitation vary by season.During spring,the increase in regional rainfall is mainly caused by the increase in heavy precipitation,while the decrease in regional precipitation is mainly caused by the decrease in weak precipitation.During summer and autumn,the increase in regional precipitation is caused by the increase in light precipitation,while the reduction in regional rainfall is caused by the decrease in heavy precipitation.This study provides support for water resources planning and addressing droughts and floods. 展开更多
关键词 ITA PRECIPITATION trend analysis ningxia
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Reconstructing the annual precipitation variation since 1899 based on tree-ring width in the western Hedong sandy land of Ningxia 被引量:3
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作者 Wang, YaJun Gao, ShangYu +3 位作者 Ma, YuZhen Lu, RuiJie Sang, YanLi Meng, HongWei 《Journal of Arid Land》 SCIE 2010年第4期286-294,共9页
Based on the analysis of the correlation between the tree-ring width of Pinus tabulaeformis and the climate factors in the western Hedong sandy land of Ningxia, a conversion equation between the annual precipitation a... Based on the analysis of the correlation between the tree-ring width of Pinus tabulaeformis and the climate factors in the western Hedong sandy land of Ningxia, a conversion equation between the annual precipitation and the tree-ring width since 1899 was reconstructed. The results of cross verification indicated that the conversion equation is stable and the reconstructed results are reliable. The result of reconstructed annual precipitation showed the remarkable fluctuation of precipitation and dry-to-wet variation before the 1940s. The smaller fluctuation and high frequent changes of precipitation occurred during the period of 1940s-1980s and after the 1980s the change trend of the precipitation became high periodic extent and low frequent. The study found that there were some coincidences with the climate change in Changling Mountains, Helan Mountains and the east of Qilian Mountains. The relatively dry periods in the beginning of 20th century, 1920s to 1930s, the end of the 20th century and 2004 to 2006 in the western Hedong sandy land of Ningxia accelerated the desertification, while the relatively humid period during the periods of the 1910s-1920s, 1930s-1940s and 1990s is favorable to prevent and control the desertification, and to weaken the climate warming and drying. The periods of annual precipitation variation in the western Hedong sandy land of Ningxia since 1899 are approximately 2-4 years, 5-7 years and 10 years. 展开更多
关键词 Hedong sandy land of ningxia tree-ring width annual precipitation CORRELATION
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Response of vegetation restoration to climate change and human activities in Shaanxi-Gansu- Ningxia Region 被引量:15
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作者 LI Shuangshuang YAN dunping LIU Xinyan WAN Jia 《Journal of Geographical Sciences》 SCIE CSCD 2013年第1期98-112,共15页
The "Grain for Green Project" initiated by the governments since 1999 were the dominant contributors to the vegetation restoration in the agro-pastoral transitional zone of northern China. Climate change and human a... The "Grain for Green Project" initiated by the governments since 1999 were the dominant contributors to the vegetation restoration in the agro-pastoral transitional zone of northern China. Climate change and human activities are responsible for the improvement and degradation to a certain degree. In order to monitor the vegetation variations and clarify the causes of rehabilitation in the Shaanxi-Gansu-Ningxia Region, this paper, based on the MODIS-NDVI and climate data during the period of 2000-2009, analyzes the main charac- teristics, spatial-temporal distribution and reasons of vegetation restoration, using methods of linear regression, the Hurst Exponent, standard deviation and other methods. Results are shown as follows. (1) From 2000 to 2009, the NDVI of the study area was improved progres- sively, with a linear tendency being 0.032/10a, faster than the growth of the Three-North Shelter Forest Program (0.007/10a) from 1982 to 2006. (2) The vegetation restoration is characterized by two fast-growing periods, with an "S-shaped" increasing curve. (3) The largest proportion of the contribution to vegetation restoration was observed in the slightly improved area, followed by the moderate and the significantly improved area; the degraded area is distributed sporadically over southern part of Ningxia Hui Autonomous Region as well as eastern Dingbian of Shaanxi province, Huanxian and Zhengyuan of Gansu province. (4) Climate change and human activities are two driving forces in vegetation restoration; more- over anthropogenic factors such as "Grain for Green Project" were the main causes leading to an increasing trend of NDVI on local scale. However, its influencing mechanism remains to be further investigated. (5) The Hurst Exponent of NDVI time series shows that the vegetation restoration was sustainable. It is expected that improvement in vegetation cover will expand to the most parts of the region. 展开更多
关键词 the vegetation cover "Grain for Green Project" spatial-temporal vegetation patterns climate change Shaanxi- Gansu-ningxia Region
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Preliminary analysis of teleseismic receiver functions of the Ningxia and its adjacent area 被引量:2
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作者 Xiaoqing Xu Xuzhang Shen +2 位作者 Chang Ming Guofu Luo Yao Lin 《Earthquake Science》 CSCD 2012年第1期47-53,共7页
The teleseismic receiver functions of digital seismic network of Ningxia and its adjacent area are calculated with two different Gauss filter factors. The accuracy and stability of the receiver functions are discussed... The teleseismic receiver functions of digital seismic network of Ningxia and its adjacent area are calculated with two different Gauss filter factors. The accuracy and stability of the receiver functions are discussed. The h-k stacking method is applied to estimate the crustal thickness and velocity ratio beneath seismic stations. The results indicate that there are sharp changes of crustal thickness and velocity ratio in the studied region. This region is located in the northeastern margin of Tibet, and also a junction of several first-grade blocks. The large contrast of crustal structure in this region is considered to be resulted from the interaction of these blocks. Our results are helpful to construct the completed model of the formation and evolution of the Tibet. Some local structures are also discussed combining with the geological faults. 展开更多
关键词 receiver function ningxia crustal thickness velocity ratio
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Strategic transformation of regionalization for the agricultural comprehensive development: The example of Ningxia Hui Autonomous Region in China 被引量:2
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作者 史文娇 胡云锋 +9 位作者 石晓丽 王宗 闫慧敏 徐自为 任博 匡文慧 徐新良 程维明 陈延 武东波 《Journal of Geographical Sciences》 SCIE CSCD 2016年第12期1675-1688,共14页
Strategic transformation of regionalization for agricultural comprehensive development(ACD) was presented by the Ministry of Finance of the People's Republic of China(MOF) in 2014. The regionalization is the premi... Strategic transformation of regionalization for agricultural comprehensive development(ACD) was presented by the Ministry of Finance of the People's Republic of China(MOF) in 2014. The regionalization is the premise and basis of the sustainable development and improved competitiveness for agriculture. Based on the environmental resources related to agriculture, such as cropland, climate, water resources, terrain, geomorphology, patterns of the ACD projects, distribution of ecological planning, etc., we devised 13 indices using the geographic comprehensive regionalization method. The indices took into account a combination of dynamic and static, qualitative and quantitative, as well as agricultural and ecological factors. The strategic transformation of regionalization for the ACD in Ningxia Hui Autonomous Region of China was performed; seven types were included: prioritized regions, prioritized and restricted regions, protected regions, protected and restricted regions, restricted and prioritized regions, restricted and protected regions, and restricted regions. A further 24 subtypes were used based on locations and ecological zones. The regionalization results showed that prioritized regions were mainly in northern Ningxia, the most suitable area for agriculture. The protected and restricted regions were in central and southern Ningxia. In the central part, drought was the limiting factor for agriculture, and water conservation projects there should be supported. The ecological environment is fragile in southern Ningxia, so there is a need for ecologically sound agriculture to be developed in this region. Such regionaliza-tion could achieve two goals, namely agricultural conservation and eco-environmental protection. It was performed following the requirement for scientific regionalization to include three types of regions(prioritized regions, protected regions, and restricted regions), and was applied at the township scale in a provincial or autonomous region for the first time. The results provide both guidance for the strategic transformation of the ACD in Ningxia, and a reference for similar work in other provinces. 展开更多
关键词 agricultural comprehensive development (ACD) REGIONALIZATION sustainable development indices ningxia
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