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Determinants of Food Security in Selected Agro-pastoral Communities of Somali and Oromia Regions, Ethiopia 被引量:1
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作者 Kwadwo Asenso-Okyere Daniel Ayalew Mekonnen Elias Zerfu 《Journal of Food Science and Engineering》 2013年第9期453-471,共19页
In spite of receiving a significant amount of food aid, achieving food security has been a major problem in Ethiopia. The claim is evidenced from the 2010 Global Hunger Index where the country fared dismally, coming o... In spite of receiving a significant amount of food aid, achieving food security has been a major problem in Ethiopia. The claim is evidenced from the 2010 Global Hunger Index where the country fared dismally, coming only fourth from the bottom. There are several factors attributing to this problem of food insecurity in a country like Ethiopia which depends highly on agriculture and allied activities. Some of the factors can be linked to low food production and productivity thereby leading to pervasive poverty. In order to assess these factors, the study was conducted on some selected members of agro-pastoral communities of Somali and Oromia regions in Ethiopia. Using availability of food in the household for the last one month as a proxy for food security, the estimated results of a logistic regression model indicated that the most significant factors affecting household food security are educational level of the spouse and that of the household head, size of farm land, availability of household assets including livestock, peace and security. The paper suggests some leads to how these amenities and resources can be provided to household members as they endeavor to reduce food insecurity. 展开更多
关键词 Household food security HUNGER food availability agro-pastoral Ethiopia.
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Thermospheric neutral wind studies over the equatorial region:A review
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作者 Siti Syazwani Nasuha Idahwati Sarudin +1 位作者 Nurul Shazana Abdul Hamid Ahmad Fairuz Omar 《Earth and Planetary Physics》 EI CAS 2025年第1期81-100,共20页
Thermospheric neutral winds(TNWs)refer to the neutral gases in the thermosphere circulating as tides,which play a crucial role in the dynamics of the thermosphere-ionosphere system(TIS).Global geospace neutral winds,p... Thermospheric neutral winds(TNWs)refer to the neutral gases in the thermosphere circulating as tides,which play a crucial role in the dynamics of the thermosphere-ionosphere system(TIS).Global geospace neutral winds,particularly over the magnetic equator,have been a subject of study for several decades.However,despite the known importance of neutral winds,a comprehensive understanding and characterization of the winds is still lacking.Various ground-based and satellite missions have provided valuable information on the contribution of neutral winds to the global atmospheric dynamics.However,efforts in the global monitoring of neutral winds are still lacking,and the drivers behind the behavior of TNWs as well as their influence on the TIS remain incomplete.To address these knowledge gaps in the global circulation of TNWs,it is crucial to develop a deep understanding of the neutral wind characteristics over different regions.The low-latitude equatorial region in particular has been observed to exert complex influences on TNWs because of the unique effects of the Earth’s magnetic field at the dip equator.Studying neutral winds over this region will provide valuable insights into the unique dynamics and processes that occur in this region,thereby enhancing our understanding of their role in the overall dynamics of the TIS.Additionally,through empirical observations,an improved ability to accurately model and predict the behavior of this region can be achieved.This review article addresses challenges in understanding equatorial winds by reviewing historical measurements,current missions,and the interactions of ionospheric and thermospheric phenomena,emphasizing the need for comprehensive measurements to improve global atmospheric dynamics and weather forecasting. 展开更多
关键词 thermospheric neutral wind thermosphere-ionosphere system dip equator equatorial region
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Burden of mental disorders and risk factors in the Western Pacific region from 1990 to 2021
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作者 Ya-Xin Xu Xiao-Xuan Niu +8 位作者 Wen-Chang Jia Jing Wen Xue-Lin Cheng Yan Han Ming-Hui Peng Jing Zhou Yao Liu Sun-Fang Jiang Xiao-Pan Li 《World Journal of Psychiatry》 SCIE 2025年第1期93-105,共13页
BACKGROUND The burden of mental disorders(MD)in the Western Pacific Region(WPR)re-mains a critical public health concern,with substantial variations across demogra-phics and countries.AIM To analyze the burden of MD i... BACKGROUND The burden of mental disorders(MD)in the Western Pacific Region(WPR)re-mains a critical public health concern,with substantial variations across demogra-phics and countries.AIM To analyze the burden of MD in the WPR from 1990 to 2021,along with associated risk factors,to reveal changing trends and emerging challenges.METHODS We used data from the Global Burden of Disease 2021,analyzing prevalence,incidence,and disability-adjusted life years(DALYs)of MD from 1990 to 2021.Statistical methods included age-standardisation and uncertainty analysis to address variations in population structure and data completeness.RESULTS Between 1990 and 2021,the prevalence of MD rose from 174.40 million cases[95%uncertainty interval(UI):160.17-189.84]to 234.90 million cases(95%UI:219.04-252.50),with corresponding DALYs increasing from 22.8 million(95%UI:17.22-28.79)to 32.07 million(95%UI:24.50-40.68).During this period,the burden of MD shifted towards older age groups.Depressive and anxiety disorders were predominant,with females showing higher DALYs for depressive and anxiety disorders,and males more affected by conduct disorders,attention-deficit hyperactivity disorder,and autism spectrum disorders.Australia,New Zealand,and Malaysia reported the highest burdens,whereas Vietnam,China,and Brunei Darussalam reported the lowest.Additionally,childhood sexual abuse and bullying,and intimate partner violence emerged as significant risk factors.CONCLUSION This study highlights the significant burden of MD in the WPR,with variations by age,gender,and nation.The coronavirus disease 2019 pandemic has exacerbated the situation,emphasizing the need for a coordinated response. 展开更多
关键词 Mental disorders Western pacific region Global Burden of Disease Risk factors Disability-adjusted life years
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An Overview of Coordinated Regional Development in China Utilizing CiteSpace Software
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作者 MEI Zhao 《Journal of Landscape Research》 2025年第1期54-58,共5页
The coordinated regional development strategy,recognized as one of China’s seven development strategies,plays a crucial role in reducing regional development disparities,optimizing resource allocation,and facilitatin... The coordinated regional development strategy,recognized as one of China’s seven development strategies,plays a crucial role in reducing regional development disparities,optimizing resource allocation,and facilitating high-quality development.This study analyzes a total of 418 relevant publications from China spanning the years 1998 to 2022.Utilizing CiteSpace software,a visualization analysis of keyword cooccurrence,mutation,and other bibliometric characteristics was conducted.The findings indicate that the number of publications during the specified period exhibited a fluctuating upward trend,with a notable increase observed after 2018.Furthermore,the research demonstrated a weak interdisciplinary crossover and a low intensity of collaboration among authors.The primary thematic areas of focus were identified as follows:connotation,mechanisms,countermeasure and suggestion,and evaluation. 展开更多
关键词 Coordinated regional development CITESPACE VISUALIZATION Graphical analysis
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Effects of clay content distribution on soil hydrothermal responses in the Lake Chad region:Numerical investigation
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作者 Ni An Teodolina Lopez +3 位作者 Raphael Antoine Yujun Cui Weikang Song Haijun Hu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1786-1800,共15页
Understanding water dynamics under the effect of climatic conditions is important to improve water sustainability over the medium-and long-term.Clay content can affect soil hydrothermal properties,and hence modify wat... Understanding water dynamics under the effect of climatic conditions is important to improve water sustainability over the medium-and long-term.Clay content can affect soil hydrothermal properties,and hence modify water and heat exchange between soil and atmosphere,e.g.evapotranspiration and infiltration.This work aims to develop a numerical approach to explore the influence of clay content on soil hydrothermal response to the timely climatic conditions in the Lake Chad region,Sahel Region of west-central Africa.The meteorological information at the studied points,i.e.points A and B with a clay content of 8.3%and 25%,during the year 2008 is collected from ERA5-Land hourly data.The numerical results allow for understanding the effect of clay content on the hydrothermal response of the surface soil layer.Specifically,the soil surface temperature under point A is lower than that under point B during the dry season due to the dominant effect of heat conduction.However,the converse tendency is observed during the wet season because of the combined effect of heat conduction and latent heat.The variations of soil volumetric water content are closely related to the timely interaction between the soil and atmosphere,in addition to the hydrothermal properties of soil.Moreover,the outcomes of this work improve the understanding of the heat and water dynamics under the effect of climatic conditions and clay content,and provide further insights into the potential water protection in arid and semi-arid regions in the future. 展开更多
关键词 Clay content Soil hydrothermal response Lake Chad region Numerical investigation Soil surface temperature
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Research and Practice on the Specialty Construction of Acupuncture and Massage to Serve the Regional Economic and Social Development
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作者 Mingjun LIU Xiaochao GANG +2 位作者 Changchun MA Chongwen ZHONG Jianzhong CUI 《Asian Agricultural Research》 2025年第3期40-42,共3页
In order to effectively implement China s national strategy of developing the country through science and education and strengthening the country through talents,it is essential to continue to strengthen the system of... In order to effectively implement China s national strategy of developing the country through science and education and strengthening the country through talents,it is essential to continue to strengthen the system of cultivating talents in Chinese medicine.This will enable the country to more effectively serve the development needs of the regional economy and society.It is of particular importance to further develop Chinese medicine-related specialties in this process,such as acupuncture and massage.By conducting meticulous research and practical investigation into the specialty construction of acupuncture and massage,we are able to significantly enhance the quality of training for those pursuing a career in Chinese medicine.This,in turn,strengthens the overall capacity of the field to contribute to the economic and social development of the region.This is not only crucial for the advancement of TCM education,but also offers a valuable point of reference for further research and practice in the domain of medical education. 展开更多
关键词 regional economic and social development Acupuncture and massage Specialty construction of TCM Medical education
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Styles and Characteristics of Thematic Art Creation in Hong Kong,Macao,and Taiwan Regions
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作者 Yanqing Liu 《Journal of Contemporary Educational Research》 2025年第1期255-261,共7页
This article explores the styles and characteristics of thematic art creation in Hong Kong,Macao,and Taiwan regions,analyzing the uniqueness of these regions’artistic backgrounds,artistic languages,theme selections,a... This article explores the styles and characteristics of thematic art creation in Hong Kong,Macao,and Taiwan regions,analyzing the uniqueness of these regions’artistic backgrounds,artistic languages,theme selections,and expressive techniques.The art creation in Hong Kong,Macao,and Taiwan regions is deeply influenced by traditional Chinese culture while incorporating Western artistic elements,exhibiting a diversified artistic style.Thematic art creation in these three regions has its own distinct features,including a deep exploration of local culture and a sensitive capture of the spirit of the times,which together constitute a rich and colorful artistic landscape in Hong Kong,Macao,and Taiwan regions. 展开更多
关键词 Hong Kong Macao and Taiwan regions Thematic art creation Artistic style
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Geographical Indications and Regional Public Brands of the Whole Rice Industry Chain in the Yangtze River Economic Belt
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作者 Min ZHANG Li GAO +2 位作者 Dongjing LI Juncheng ZHU Bin HU 《Asian Agricultural Research》 2025年第1期1-13,共13页
The Yangtze River Economic Belt is the main rice producing area in China.The rice industry chain is the agricultural pillar industry chain of this economic belt and it is the key to ensuring national food security and... The Yangtze River Economic Belt is the main rice producing area in China.The rice industry chain is the agricultural pillar industry chain of this economic belt and it is the key to ensuring national food security and promoting comprehensive rural revitalization.This study discusses the entire rice industry chain in the Yangtze River Economic Belt from the national rice production functional zones,agricultural product quality and safety,national famous and excellent new agricultural products,national specialty agricultural products,"China's good grain and oil"products,and national advantageous characteristic industrial clusters.Then,it discusses the geographical indications of rice and its products in this economic belt from geographical indication products,geographical indication trademarks,agricultural geographical indications,geographical indication standards,geographical indication special indications,national geographical indication product protection demonstration zones,and Chinese geographical indication products protected by the European Union.In addition,it analyzes the five main problems between geographical indications and public brands,such as the limited use of geographical indication specific signs and the imperfect intellectual property protection system for geographical indications.Finally,it proposes eight strategies,including promoting the high-quality development of the entire rice industry chain,creating a geographical indication regional public brand for rice and its products,and implementing geographical indication protection projects. 展开更多
关键词 Yangtze River Economic Belt Rice and its products Entire industry chain Geographical indication regional public brand
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Spatial Patterns and Controlling Factors of Soil Organic Carbon and Total Nitrogen in the Three River Headwaters Region,China
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作者 CUI Qiao LI Zongxing +2 位作者 FENG Qi ZHANG Baijuan ZHAO Yue 《Chinese Geographical Science》 2025年第1期131-148,共18页
The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate ... The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate change on the structure,function,and services of the ecosystem.However,the spatial distribution and controlling factors of SOC and TN across various soil layers and vegetation types within this unique ecosystem remain inadequately understood.In this study,256 soil samples in 89 sites were collected from the Three River Headwaters Region(TRHR)in China to investigate SOC and TN and to explore the primary factors affecting their distribution,including soil,vegetation,climate,and geography factors.The results show that SOC and TN contents in 0-20,20-40,40-60,and 60-80 cm soil layers are 24.40,18.03,14.04,12.40 g/kg and 2.46,1.90,1.51,1.17 g/kg,respectively;with higher concentrations observed in the southeastern region compared to the northwest of the TRHR.One-way analysis of variance reveals that SOC and TN levels are elevated in the alpine meadow and the alpine shrub relative to the alpine steppe in the 0-60 cm soil layers.The structural equation model explores that soil water content is the main controlling factor affecting the variation of SOC and TN.Moreover,the geography,climate,and vegetation factors notably indirectly affect SOC and TN through soil factors.Therefore,it can effectively improve soil water and nutrient conditions through vegetation restoration,soil improvement,and grazing management,and the change of SOC and TN can be fully understood by establishing monitoring networks to better protect soil carbon and nitrogen. 展开更多
关键词 controlling factors different soil layers soil organic carbon(SOC) soil total nitrogen(TN) alpine ecosystem the Three River Headwaters region(TRHR) China
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Impact of livelihood diversification of rural households on their ecological footprint in agro-pastoral areas of northern China 被引量:22
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作者 HAO Haiguang ZHANG Jiping +2 位作者 LI Xiubin ZHANG Huiyuan ZHANG Qiang 《Journal of Arid Land》 SCIE CSCD 2015年第5期653-664,共12页
Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data... Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data of Taibus Banner, Duolun county and Zhengxiangbai Banner in the Inner Mongolia autonomous region of China, we identified the impact of livelihood diversification on ecosystems in these agro-pastoral areas by using the ecological footprint theory and methodology together with the one-way analysis of variance (ANOVA) and correlation analysis methods. In 2011, the total ecological footprint of consumption (EFC) was 0.665 g hm2, and the total ecological footprint of production (EFP) was 2.045 g hm2, which was more than three times the EFC. The ecological footprint of arable land consumption (EFAC) accounted for a large proportion of the EFC, and the ecological footprint of grassland production (EFGP) occupied a large proportion of the EFP. Both the ecological footprint of grassland consumption (EFGC) and EFGP had a significant positive correlation with the income, indicating that income was mainly depended on livestock production and the households with higher incomes consumed more livestock prod- ucts. The full-time farming households (FTFHs) had the highest EFP, ecological footprint of arable land production (EFAP), EFGP and EFGC, followed by the part-time farming households (PTFHs) and non-farming households (NFHs), which indicated that part-time farming and non-farming employment reduced the occupancy and con- sumption of rural households on local ecosystems and natural resources to some extent. When farming households engaged in livestock rearing, both the EFAP and EFAC became smaller, while the EFP, EFC, EFGC and EFGP increased significantly. The differences in ecological footprints among different household groups should be taken into account when making ecosystem conservation policies. Encouraging the laborers who have the advantages of participating in non-farming employment to move out of the rural areas and increasing the diversification of liveli- hoods of rural households are important in reducing the environmental pressures and improving the welfare of households in the study area. Moreover, grassland should be utilized more effectively in the future. 展开更多
关键词 ecological footprint livelihood diversification livestock rearing non-farming employment rural households agro-pastoral area
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Livelihood Diversification of Farm Households and Its Impact on Cultivated Land Utilization in Agro-pastoral Ecologically-vulnerable Areas in the Northern China 被引量:6
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作者 LIU Haiyan HAO Haiguang +3 位作者 HU Xujun DU Leshan ZHANG Zhe LI Yuanyuan 《Chinese Geographical Science》 SCIE CSCD 2020年第2期279-293,共15页
The relationship between livelihood diversification of farm households and cultivated land utilization has become a core research topic related to global environmental change.Agro-pastoral ecologically-vulnerable area... The relationship between livelihood diversification of farm households and cultivated land utilization has become a core research topic related to global environmental change.Agro-pastoral ecologically-vulnerable areas face challenges such as insufficient ecosystem conservation,low agricultural production,and weak economies.In this study,215 farm households from Zhengxiangbai Banner,Taibus Banner,and Duolun County of Inner Mongolia were surveyed.The sustainable livelihoods framework of the United Kingdom(UK)Department for International Development(DFID)was used to measure the livelihood capital of these farm households.A one-way analysis of variance(ANOVA)was applied to examine the differences in the livelihood capital of different types households,and a correlation analysis was applied to analyze its impact on cultivated land utilization.Results showed that households with non-farming activities accounted for 64.7%of the total surveyed households,and non-farming employment was becoming more prevalent.Physical and financial capital was the driving factors for livelihood diversity.Each livelihood capital had key factors that affected household farmland use behaviors,such as the age of householder,the labor ratio,proportion of income,farmland scale,number of machines,and these had a significantly positive or negative influence on farmland use.Full-time farming households were more likely to transfer the land into cultivation and invest more labor,while non-farming households with high income were likely to transfer farmland out and invest more money to develop efficient farming or improve the employment skills.The results of this study suggest that policymakers need to fully consider livelihood changes of local households.It is effective to strengthen labor training,create farmland market and improve the efficiency of farmland utilization.We hope to achieve a win-win scenario to improve local economies and ecosystem conservation. 展开更多
关键词 agro-pastoral ecologically-vulnerable areas LIVELIHOOD DIVERSIFICATION CULTIVATED land UTILIZATION ecosystem conservation
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Changes in soil carbon stocks and related soil properties along a 50-year grassland-to-cropland conversion chronosequence in an agro-pastoral ecotone of Inner Mongolia,China 被引量:8
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作者 Yan JIAO Zhu XU +1 位作者 JiaoHong ZHAO WenZhu YANG 《Journal of Arid Land》 SCIE 2012年第4期420-430,共11页
Land use change significantly influences soil properties. There is little information available on the long-term effects of post-reclamation from grassland to cropland on soil properties. We compared soil carbon (C)... Land use change significantly influences soil properties. There is little information available on the long-term effects of post-reclamation from grassland to cropland on soil properties. We compared soil carbon (C) and nitrogen (N) storage and related soil properties in a 50-year cultivation chronosequence of grassland in the agro-pastoral ecotone of Inner Mongolia. Field surveys on land use changes during the period of 1955-2002 were conducted to build a chronosequence of cropland of different ages since the conversion from grassland. The results showed that soil C and N storage, soil texture, and soil nutrient contents varied with land use types and cropland ages (P〈0.01). In the 0-30 cm soil layer, the soil organic carbon (SOC) density was significantly lower in the crop- lands (3.28 kg C/m2 for C50 soil) than in the grasslands (6.32 kg C/m2). After 5, 10, 15, 20, 35, and 50 years of crop planting (years since the onset of cultivation), the SOC losses were 17%, 12%, 19%, 47%, 46%, and 48%, respec- tively, compared with the grasslands. The soil total nitrogen (TN) density of the grasslands was 65 g N/m2, and TN density of the cropland soil was 35 g N/m2 after 50 years of crop planting. Both the SOC and TN densities could be quantitatively determined by a negative exponential function of cropland age (P〈0.0001, R2=0.8528; P〈0.0001, R2=0.9637). The dissolved organic carbon (DOC) content, pH value were decreased; and the soil bulk density and soil available potassium (AK) content, clay content, and sand content were increased since the conversion of grassland into cropland during the 50-year period. Our results show soil nutrients were higher in grassland than in cropland. The conversion of grasslands to croplands induced a loss of soil C storage and changes of related soil properties. The reclamation time of cultivated soil (cropland age) had significant effects on soil properties in the study area. 展开更多
关键词 land use type cropland age GRASSLAND soil physical-chemical properties agro-pastoral ecotone
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Agricultural Vulnerability to Drought in China's Agro-pastoral Ecotone:A Case Study of Yulin City,Shaanxi Province 被引量:3
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作者 LI Yuheng CHENG Wenjing +1 位作者 ZUO Wenjie ZHANG Lingyue 《Chinese Geographical Science》 SCIE CSCD 2023年第5期934-945,共12页
Agro-pastoral ecotone of northern China is the prominent area for agricultural production,but it is also the most typical ecological fragile area with frequent drought disasters.Taking Yulin City at Shaanxi Province i... Agro-pastoral ecotone of northern China is the prominent area for agricultural production,but it is also the most typical ecological fragile area with frequent drought disasters.Taking Yulin City at Shaanxi Province in China as the case area,the paper aims to investigate the spatio-temporal changes of agricultural vulnerability to drought in China’s agro-pastoral ecotone in the period 2000 to2020.The results show that:1)the agricultural vulnerability to drought in Yulin City has shifted from high vulnerability in the period2000–2010 to low vulnerability in the period 2011–2020.2)There exist obvious spatio-temporal differences of the agricultural vulnerability to drought in Yulin City during the research period.3)Four sensitive events and 14 resilient events were identified in the research and the crops of Yulin had become more resilient to drought.Finally,the paper put forward with policy implications to make adaptive strategies of agriculture to climate change in China’s agro-pastoral ecotone in the future,e.g.,carrying out agricultural zoning based on agricultural production conditions,intensifying the construction of disaster prevention and relief system,and integrating with modern agricultural technology to develop new type agriculture. 展开更多
关键词 climate change agricultural vulnerability DROUGHT agro-pastoral ecotone Yulin City China
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Evaluation of Land Reclamation and Implications of Ecological Restoration for Agro-pastoral Ecotone: Case Study of Horqin Left Back Banner in China 被引量:3
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作者 ZHOU Jian ZHANG Fengrong +2 位作者 XU Yan GAO Yang XIE Zhen 《Chinese Geographical Science》 SCIE CSCD 2017年第5期772-783,共12页
The agro-pastoral ecotone has been recognized as the main distribution area of reserved land resource for cultivation. Accordingly, clarifying this assumption, as well as concerting land reclamation and ecological res... The agro-pastoral ecotone has been recognized as the main distribution area of reserved land resource for cultivation. Accordingly, clarifying this assumption, as well as concerting land reclamation and ecological restoration, is important to ensure food security and environmental improvement in the agro-pastoral ecotone. We selected Horqin Left Back Banner(HLBB) as the subject of our case study. The landscape ecological security pattern of this area was determined using the minimum cumulative resistance model. Over-cultivation, quantity of reserved land resource for cultivation, and changes in landscape indexes before and after land use adjustment were then analyzed. Over-cultivation is a serious problem in the agro-pastoral ecotone. Reserved land resource for cultivation is less than that considered previously, and the area of reserved land resource for cultivation in HLBB only accounts for 11.50% of total uncultivated land. With regard to changes in landscape indexes, the adjusted land use pattern is effective for anti-desertification. The compensation standard for abandoned cultivated land should be improved and the comprehensive results of ‘Grain for Green' should be evaluated to further implement ecological restoration in the agro-pastoral ecotone. 展开更多
关键词 land reclamation ecological restoration minimum cumulative resistance model agro-pastoral ecotone China
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Wavelet analysis of spring climate characteristics in arid aeolian area of agro-pastoral ecotone in China 被引量:2
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作者 Chun-xia ZOU Xiang-dong SHEN +2 位作者 Hong-yun LI Xia-zi LI Zhang-jun LI 《Water Science and Engineering》 EI CAS 2012年第3期269-277,共9页
The unique regional climate characteristics are among the main reasons for the frequent wind-sand activity in arid and cold areas in the agro-pastoral ecotone in Inner Mongolia, China. This paper focuses on the time s... The unique regional climate characteristics are among the main reasons for the frequent wind-sand activity in arid and cold areas in the agro-pastoral ecotone in Inner Mongolia, China. This paper focuses on the time series of temperature and precipitation in spring when sandstorms often occur in the area. Based on meteorological data for a 46-year period from 1959 to 2004, multi-scale variations and abrupt changes in temperature and precipitation were analyzed with the Mexican hat function (MHF) wavelet method, showing the multi-scale variation characteristics of temperature and precipitation, as well as the periods and change points at different time scales. The relationship between temperature and precipitation was obtained using the wavelet analysis method. Obvious staggered features of the variations of spring temperature and precipitation were observed in this agro-pastoral ecotone. The strongest oscillation periods of spring temperature variations were 1 and 22 years, while for precipitation, the strongest oscillation periods of variations were 2, 8, and 22 years. In addition, lower spring temperature corresponded to lower precipitation, whereas higher temperature yielded higher precipitation rate. 展开更多
关键词 spring temperature spring precipitation climate characteristics MHF waveletmethod arid aeolian area agro-pastoral ecotone
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Wind Tunnel Study of Multiple Factors Affecting Wind Erosion from Cropland in Agro-pastoral Area of Inner Mongolia,China 被引量:4
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作者 HE Ji-jun CAI Qiang-guo CAO Wen-qing 《Journal of Mountain Science》 SCIE CSCD 2013年第1期68-74,共7页
In this paper,the process of wind erosion on two kinds of soil from the agro-pastoral area of Inner Mongolia are studied using wind tunnel experiments,considering the wind speed,blown angle of wind and soil moisture c... In this paper,the process of wind erosion on two kinds of soil from the agro-pastoral area of Inner Mongolia are studied using wind tunnel experiments,considering the wind speed,blown angle of wind and soil moisture content.The results showed that the modulus of soil wind erosion increases with an increase of wind speed.When the wind speed exceeds a critical value,the soil wind erosion suddenly increases.The critical speed for both kinds of soil is within the range of 7-8m·s-1.For a constant wind speed,the rate of soil wind erosion changes from increasing to falling at a critical soil slope.The critical slope of loam soil and sandy loam soil is 20° and 10°,respectively.Soil moisture content has a significant effect on wind erosion.Soil wind erosion of both soils decreases with an increase of the soil water content in two treatments,however,for treatment two,the increasing trends of wind erosion for two soils with the falling of soil water content are no significant,especially for the loam soil,and in the same soil water content,the wind erosion of two soils in treatment one is significantly higher than treatment two,this indicates reducing the disturbance of soil surface can evidently control the soil wind erosion. 展开更多
关键词 agro-pastoral area Soil wind erosion Critical slope Wind tunnel experiment
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Does digitalization mitigate regional inequalities?Evidence from China 被引量:1
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作者 Haimeng Liu Xinyang Wang +1 位作者 Zheye Wang Yu Cheng 《Geography and Sustainability》 CSCD 2024年第1期52-63,共12页
Regional inequality significantly influences sustainable development and human well-being.In China,there exists pronounced regional disparities in economic and digital advancements;however,scant research delves into t... Regional inequality significantly influences sustainable development and human well-being.In China,there exists pronounced regional disparities in economic and digital advancements;however,scant research delves into the interplay between them.By analyzing the economic development and digitalization gaps at regional and city levels in China,extending the original Cobb-Douglas production function,this study aims to evaluate the impact of digitalization on China's regional inequality using seemingly unrelated regression.The results indicate a greater emphasis on digital inequality compared to economic disparity,with variable coefficients of 0.59 for GDP per capita and 0.92 for the digitalization index over the past four years.However,GDP per capita demonstrates higher spatial concentration than digitalization.Notably,both disparities have shown a gradual reduction in recent years.The southeastern region of the Hu Huanyong Line exhibits superior levels and rates of economic and digital advancement in contrast to the northwestern region.While digitalization propels economic growth,it yields a nuanced impact on achieving balanced regional development,encompassing both positive and negative facets.Our study highlights that the marginal utility of advancing digitalization is more pronounced in less developed regions,but only if the government invests in the digital infrastructure and education in these areas.This study's methodology can be utilized for subsequent research,and our findings hold the potential to the government's regional investment and policy-making. 展开更多
关键词 regional inequality regional disparities Digital divide DIGITALIZATION Sustainable development Economic growth Seemingly unrelated regression
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Organic Matter Accumulation in the Upper Permian Dalong Formation from the Lower Yangtze Region,South China 被引量:3
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作者 FANG Chaogang ZHANG Chengcheng +5 位作者 MENG Guixi XU Jinlong XU Naicen LI Hualing LIU Mu LIU Bo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期150-167,共18页
The Late Permian was marked by a series of important geological events and widespread organic-rich black shale depositions,acting as important unconventional hydrocarbon source rocks.However,the mechanism of organic m... The Late Permian was marked by a series of important geological events and widespread organic-rich black shale depositions,acting as important unconventional hydrocarbon source rocks.However,the mechanism of organic matter(OM)enrichment throughout this period is still controversial.Based on geochemical data,the marine redox conditions,paleogeographic and hydrographic environment,primary productivity,volcanism,and terrigenous input during the Late Permian in the Lower Yangtze region have been studied from the Putaoling section,Chaohu,to provide new insights into OM accumulation.Five Phases are distinguished based on the TOC and environmental variations.In Phase I,anoxic conditions driven by water restriction enhanced OM preservation.In Phase II,euxinic and cycling hydrological environments were the two most substantial controlling factors for the massive OM deposition.During Phase III,intensified terrestrial input potentially diluted the OM in sediment and the presence of oxygen in bottom water weakened the preservation condition.Phase IV was characterized by a relatively higher abundance of mercury(Hg)and TOC(peak at 16.98 wt%),indicating that enhanced volcanism potentially stimulated higher productivity and a euxinic environment.In Phase V,extremely lean OM was preserved as a result of terrestrial dilutions and decreasing primary productivity.Phases I,II and IV are characterized as the most prominent OM-rich zones due to the effective interactions of the controlling factors,namely paleogeographic,hydrographic environment,volcanism,and redox conditions. 展开更多
关键词 GEOCHEMISTRY redox condition primary productivity OM accumulation Lopingian/Changhsingian Lower Yangtze region
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Construction and Application of a Regional Kilometer-Scale Carbon Source and Sink Assimilation Inversion System(CCMVS-R) 被引量:2
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作者 Lifeng Guo Xiaoye Zhang +8 位作者 Junting Zhong Deying Wang Changhong Miao Licheng Zhao Zijiang Zhou Jie Liao Bo Hu Lingyun Zhu Yan Chen 《Engineering》 SCIE EI CAS CSCD 2024年第2期263-275,共13页
CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate ... CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate warming since the 1950s and leading to an increased frequency of extreme weather and climate events.In 2020,China committed to striving for carbon neutrality by 2060.This commitment and China’s consequent actions will result in significant changes in global and regional anthropogenic carbon emissions and therefore require timely,comprehensive,and objective monitoring and verification support(MVS)systems.The MVS approach relies on the top-down assimilation and inversion of atmospheric CO_(2)concentrations,as recommended by the Intergovernmental Panel on Climate Change(IPCC)Inventory Guidelines in 2019.However,the regional high-resolution assimilation and inversion method is still in its initial stage of development.Here,we have constructed an inverse system for carbon sources and sinks at the kilometer level by coupling proper orthogonal decomposition(POD)with four-dimensional variational(4DVar)data assimilation based on the weather research and forecasting-greenhouse gas(WRF-GHG)model.Our China Carbon Monito ring and Verification Support at the Regional level(CCMVS-R)system can continuously assimilate information on atmospheric CO_(2)and other related information and realize the inversion of regional and local anthropogenic carbon emissions and natural terrestrial ecosystem carbon exchange.Atmospheric CO_(2)data were collected from six ground-based monito ring sites in Shanxi Province,China to verify the inversion effect of regio nal anthropogenic carbon emissions by setting ideal and real experiments using a two-layer nesting method(at 27 and 9 km).The uncertainty of the simulated atmospheric CO_(2)decreased significantly,with a root-mean-square error of CO_(2)concentration values between the ideal value and the simulated after assimilation was close to 0.The total anthropogenic carbon emissions in Shanxi Province in 2019 from the assimilated inversions were approximately 28.6%(17%-38%)higher than the mean of five emission inventories using the bottomup method,showing that the top-down CCMVS-R system can obtain more comprehensive information on anthropogenic carbon emissions. 展开更多
关键词 CCMVS-R regional carbon assimilation system Anthropogenic carbon emissions CO_(2) POD 4DVar
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Trends of surface ozone based on hourly concentrations in the Beijing–Tianjin–Hebei region during 2017–2021 被引量:1
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作者 Xiaoyan Wang Huihui Zheng +3 位作者 Bing Liu Shuyan Xie Yonghai Huang Shuai Wang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第6期26-32,共7页
As a typical secondary air pollutant,surface ozone has been monitored routinely since 2013 in China.Most studies on the spatiotemporal variation of ozone have been centered around the daily maximum 8-h average,with li... As a typical secondary air pollutant,surface ozone has been monitored routinely since 2013 in China.Most studies on the spatiotemporal variation of ozone have been centered around the daily maximum 8-h average,with little attention paid to the trends of hourly ozone,especially hourly ozone exceedances.Focusing on hourly ozone exceedances and peak values,the spatiotemporal trends of hourly ozone at 77 sites in 13 cities of the Beijing-Tianjin-Hebei(BTH)region during 2017-2021 were analyzed in this study.The number of hours with exceedances(N_(H200))in 2019 was nearly three times that of 2021.On a five-year average,the percentage of cumulative NH200 in June accounted for up to 40.5%of all hourly exceedances.Cities in central Hebei Province had the highest cumulative annual N_(H200).June had the highest average hourly ozone exceeded multiples of 0.158.The top two cities with the highest average exceeded multiple were Tangshan(0.166)and Beijing(0.158).Tangshan and Xingtai ranked as the top two in terms of the mean of the 10 highest daily maximum ozone concentrations(MTDM),with 286.74 and 285.37μg m^(−3),respectively.The gap between the MTDM and the daily maximum of hourly ozone averaged over all sites had narrowed to 97.88μg m^(−3) in 2021,much lower than that in other years,which indicated that the stability and convergence of ozone pollution in BTH region had been enhanced in 2021 to some extent. 展开更多
关键词 Surface ozone Hourly concentration Ozone exceedance Peak value Beijing-tianjin-hebei region
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