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Historical biogeography and evolutionary diversification of Lilium(Liliaceae): New insights from plastome phylogenomics 被引量:2
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作者 Nian Zhou Ke Miao +4 位作者 Changkun Liu Linbo Jia Jinjin Hu Yongjiang Huang Yunheng Ji 《Plant Diversity》 SCIE CAS CSCD 2024年第2期219-228,共10页
Here,we infer the historical biogeography and evolutionary diversification of the genus Lilium.For this purpose,we used the complete plastomes of 64 currently accepted species in the genus Lilium(14plastomes were newl... Here,we infer the historical biogeography and evolutionary diversification of the genus Lilium.For this purpose,we used the complete plastomes of 64 currently accepted species in the genus Lilium(14plastomes were newly sequenced)to recover the phylogenetic backbone of the genus and a timecalibrated phylogenetic framework to estimate biogeographical history scenarios and evolutionary diversification rates of Lilium.Our results suggest that ancient climatic changes and geological tectonic activities jointly shaped the distribution range and drove evolutionary radiation of Lilium,including the Middle Miocene Climate Optimum(MMCO),the late Miocene global cooling,as well as the successive uplift of the Qinghai-Tibet Plateau(QTP)and the strengthening of the monsoon climate in East Asia during the late Miocene and the Pliocene.This case study suggests that the unique geological and climatic events in the Neogene of East Asia,in particular the uplift of QTP and the enhancement of monsoonal climate,may have played an essential role in formation of uneven distribution of plant diversity in the Northern Hemisphere. 展开更多
关键词 Asian monsoon Climatic changes Distribution range Evolutionary complexity Radiative diversification Species diversity Qinghai-Tibet Plateau(QTP)
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Interference of Local Government, Industrial Concentrative Rate and Corporate Diversification
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作者 LIU Shan-min 《Journal of Modern Accounting and Auditing》 2007年第2期45-55,81,共12页
This paper studies the effects of internal and external environments on the strategic decision-making of diversification using the cross-sectional data of China's 1 033 non-financial listed companies in Shenzhen and ... This paper studies the effects of internal and external environments on the strategic decision-making of diversification using the cross-sectional data of China's 1 033 non-financial listed companies in Shenzhen and Shanghai Exchange. Corporate external-environment is substituted by index of marketization and market concentrative rate, and internal-environment is substituted by governance framework and financial status. The multi-regression analysis shows that the strategic decision-making of diversification is prominently affected by external factors such as index of marketization and market concentrative rate, and is significantly negative related to the proportion of state-owned shares and corporate shares. There is no correlation between diversification and whether directors hold concurrently, or manager compensation, cash flow, and debt ratio. 展开更多
关键词 index of marketization market concentrative rate diversification related diversification unrelated diversification
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Eurozone Equity Market Diversification: Is It Still Worth?
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作者 Fabio Pizzutilo 《Chinese Business Review》 2012年第1期29-43,共15页
The paper aims at verifying if there still are advantages in diversification inside the Eurozone despite the economic and monetary unification process. The results show unambiguously that notwithstanding the high degr... The paper aims at verifying if there still are advantages in diversification inside the Eurozone despite the economic and monetary unification process. The results show unambiguously that notwithstanding the high degree of correlation between the Eurozone stock markets, opportunities for diversification still exist. The introduction of constraints on short selling significantly reduces these benefits. Investors from the European leading countries would have greatly benefitted from a Eurozone portfolio diversification strategy. The advantages of diversification appear to change significantly over time and from country to country. The results are also conclusive in reflecting the instability of the historical mean-variance data. 展开更多
关键词 international diversification Eurozone equity markets Eurozone diversification Eurozone efficientfrontier mean variance analysis European monetary union Eurozone correlation analysis
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Diversification of Autonomous Reading Materials for English Major
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作者 刘佳 《海外英语》 2015年第12期253-253,256,共2页
Autonomous learning and its importance has attracted more and more attention,on the basis of which,independent read-ing activities should emphasizes the student as the center in the activity.So the choice of independe... Autonomous learning and its importance has attracted more and more attention,on the basis of which,independent read-ing activities should emphasizes the student as the center in the activity.So the choice of independent reading materials should bebased on their requirement.The materials should have the features of interesting and informative,varied style,content suitable forteaching materials,etc.At last how English teacher guide and conduct the students’activities of self-monitoring and self-assess-ment. 展开更多
关键词 AUTONOMOUS LEARNING ABILITY AUTONOMOUS READING diversification CHOICE
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Relationship between Prosopis juliflora invasion and livelihood diversification in the South Afar region,Northeast Ethiopia
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作者 Wakshum Shiferaw Sebsebe Demissew +1 位作者 Tamrat Bekele Ermias Aynekulu 《Regional Sustainability》 2020年第1期82-92,共11页
This study assessed the effects of Prosopis juliflora invasion on livelihood diversification and evaluated the determinants of livelihood diversification in two districts in the South Afar region of Northeast Ethiopia... This study assessed the effects of Prosopis juliflora invasion on livelihood diversification and evaluated the determinants of livelihood diversification in two districts in the South Afar region of Northeast Ethiopia.Using random sampling method,154 households and 2 focus groups composed of 10 individuals were selected from four sites in the two districts.The relationship between P.juliflora invasion and incomes obtained from P.juliflora varied across the study sites.In Awash Fentale District and Amibara District,11.0%and 3.2%of households,respectively,earned income from P.juliflora charcoal production.In total,14.3%of households were involved in charcoal production.In addition,19.9%of households earned income from selling P.juliflora pods and wood materials in the two districts.With the exception of income from P.juliflora charcoal production,the sex of households did not affect incomes from other livelihood activities.Moreover,household educational attainment significantly affected income obtained from vegetables,fruits,and cereal crops.Male householders were engaged in more diverse livelihood activities than female householders.Reversing the severe invasion of P.juliflora on grazing and woodlands in the region is advisable through integrated natural resources,pastoralist participation,and multidisciplinary research strategies. 展开更多
关键词 Determinant factors Livelihood diversification Household incomes Prosopis juliflora invasion Simpson’s diversification index(SDI)
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Livelihood diversification and cropland use pattern in agro-pastoral mountainous region of eastern Tibetan Plateau 被引量:26
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作者 ZHANG Liping ZHANG Yili +1 位作者 YAN dianzhong WU Yingying 《Journal of Geographical Sciences》 SCIE CSCD 2008年第4期499-509,共11页
This study examined livelihood diversification and cropland use pattern in Keerma village, located in Jinchuan County, eastern Tibetan Plateau. Through stratified random sampling survey, participatory rural appraisal,... This study examined livelihood diversification and cropland use pattern in Keerma village, located in Jinchuan County, eastern Tibetan Plateau. Through stratified random sampling survey, participatory rural appraisal, investigation of households' plots and statistical methods, 63 households and 272 cropland plots were systemically investigated and sampled. The results show: (1) Different types of household have variety livelihood strategies, portfolio and income. Livelihood diversification and introducing and expanding off-farm activities can be the future trend, whereas, adverse natural environment, socio-economic conditions and peasants' capabilities together affect sustainable livelihood and land use. (2) Each livelihood strategy has its own impact on land use, mainly affecting land use type and land use intensi- fication level. (3) Diversification into off-farm activities could be the key of building sustainable livelihood and the essential approach of realizing sustainable land use in the region. 展开更多
关键词 HOUSEHOLD livelihood diversification off-farm employment land use Tibetan Plateau
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Livelihood diversification of farmers and nomads of eastern transect in Tibetan Plateau 被引量:28
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作者 YAN Jianzhong WU Yingying +1 位作者 ZHANG Yili ZHOU Shaobin 《Journal of Geographical Sciences》 SCIE CSCD 2010年第5期757-770,共14页
Livelihoods of farmers and nomads in Tibetan Plateau are severely affected by grassland and herbal resources degeneration. How to help them achieve livelihood diversi- fication is a key sustainable development issue. ... Livelihoods of farmers and nomads in Tibetan Plateau are severely affected by grassland and herbal resources degeneration. How to help them achieve livelihood diversi- fication is a key sustainable development issue. This paper examines livelihood assets, live- lihood diversification level and livelihood strategies of farmers and nomads in 3 regions of eastern transect in Tibetan Plateau. The results show that livelihood diversification is a popular strategy. From high mountain gorge region to mountain plateau region and plateau region, livelihood diversification level is reduced, and livelihood activities and proportion of extended livelihood also decrease. Livelihood assets and livelihood diversification level decrease with the increase of elevation, mainly shown in human assets and natural assets. Livelihood diversification level is highly correlative with livelihood assets, mainly shown in natural assets, human assets and social assets. Livelihood improvement strategies of farmers and nomads are still based on existing livelihood assets, mainly raising livestock and digging herbs, and less farmers and nomads consider off-farm employment or doing business. Nomads in plateau region should learn much from experiences of extended livelihoods of people in high mountain gorge region and mountain plateau region. Therefore, aids of governments should focus on relieving restricted factors of livelihood diversification and help them improve their abilities to build up extended type livelihoods. 展开更多
关键词 Tibetan Plateau TRANSECT livelihood diversification livelihood assets
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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:23
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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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Crop Diversification in Coping with Extreme Weather Events in China 被引量:14
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作者 HUANG Ji-kun JIANG Jing +1 位作者 WANG Jin-xia HOU Ling-ling 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第4期677-686,共10页
Apart from the long-term effects of climate change, the frequency and severity of extreme weather events have been increasing. Given the risks posed by climate change, particularly the changes in extreme weather event... Apart from the long-term effects of climate change, the frequency and severity of extreme weather events have been increasing. Given the risks posed by climate change, particularly the changes in extreme weather events, the question of how to adapt to these changes and mitigate their negative impacts has received great attention from policy makers. The overall goals of this study are to examine whether farmers adapt to extreme weather events through crop diversification and which factors influence farmers' decisions on crop diversification against extreme weather events in China. To limit the scope of this study, we focus on drought and flood events only. Based on a unique large-scale household survey in nine provinces, this study finds that farmers respond to extreme weather events by increasing crop diversification. Their decision to diversify crops is significantly influenced by their experiences of extreme weather events in the previous year. Such results are understandable because farmers' behaviors are normally based on their expectations. Moreover, household characteristics also affect farmers' decisions on crop diversification strategy, and their effects differ by farmers' age and gender. This paper concludes with several policy implications. 展开更多
关键词 ADAPTATION extreme weather event climate change crop diversification FARMER
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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:9
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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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The future of mountain agriculture amidst continual farm-exit, livelihood diversification and outmigration in the Central Himalayan villages 被引量:5
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作者 Niyati NAUDIYAL Kusum ARUNACHALAM Ujjwal KUMAR 《Journal of Mountain Science》 SCIE CSCD 2019年第4期755-768,共14页
Agrarian patterns in mountain ecosystems have seen a considerable change in the past decades with a vast proportion of the population abandoning traditional agriculture and diversifying their livelihood options, prima... Agrarian patterns in mountain ecosystems have seen a considerable change in the past decades with a vast proportion of the population abandoning traditional agriculture and diversifying their livelihood options, primarily through out-migration. This trend is especially common amongst the subsistence based family-farming communities in developing countries. This study aims at assessing methods of livelihood diversification and factors influencing farm-exit in Central Himalayan villages of Uttarakhand, India, while trying to understand local perspectives on challenges in pursuing agriculture as a viable livelihood option. We collected qualitative and quantitative data from 951 households across 60 villages evenly distributed across six hill districts of Uttarakhand, using key-person interviews and household surveys. The results of the study highlight that farm-exit is significantly influenced by livelihood diversification, number of migrants, number of female family members, and availability of irrigation facilities. In general, perception of the respondents towards agriculture as a viable livelihood option is rather unenthusiastic, with 87% of the respondents citing human wildlife conflict as the main challenge in pursuing farming, amongst several other challenges. Diversification is an integral component of present rural economy with 80.13% of the total population dependent on more than one source of income, to maintain their livelihoods. However, there is no statistically significant influence of livelihood diversification on annual income of the household. If agro-based entrepreneurial ventures are to be promoted in the region there is an urgent need for timely introduction of radical policy, institutional, and land-reforms. Economic uplifting of the local population through such efforts can also be a possible solution to the growing trends of out-migration in the state. 展开更多
关键词 Agriculture diversification Rural livelihoods Migration HIMALAYA
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