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Analysis of Factors Associated with the Abandonment of Nutritional Recovery among Parents of Severely Malnourished Children Aged 6 to 59 Months in the Health District of Titao, Burkina Faso
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作者 Aminata Gansore Patrice Ngangue +7 位作者 Birama Apho Ly Ludovic K. N’Tcha Douglas Mbang Massom Gbètogo Maxime Kiki Josiane Seu Nestor Bationo Noufou Gustave Nana Fla Koueta 《Open Journal of Nursing》 2024年第9期477-490,共14页
Introduction: In Burkina Faso, undernutrition is a public health problem associated with more than 40% of infant and child mortality. Undernutrition management is complex, and there is often a risk of treatment abando... Introduction: In Burkina Faso, undernutrition is a public health problem associated with more than 40% of infant and child mortality. Undernutrition management is complex, and there is often a risk of treatment abandonment. Studies on this topic have not explored the influence of environmental and therapeutic factors on parental compliance. This study proposes an analysis of factors influencing the abandonment of nutritional recovery by parents of malnourished children aged 6 to 59 months in ambulatory care. Methods: This was a descriptive and exploratory qualitative study. Data collection took place in February 2020. Data were collected from seventeen (17) participants via in-depth interviews (IDI) and direct observation. The IDIs were transcribed verbatim and thematically analyzed using Nvivo software. Results: The results revealed that factors related to the physical environment, such as geographical inaccessibility, pastoral occupation, displacement at auriferous sites, and insecurity, are important causes of nutritional recovery abandonment. They also prove that factors related to the social environment, such as lack of family and social support, feelings of shame, stigmatization, occupation of the mother, and social events, lead to this abandonment. In addition, therapeutic factors such as interruptions of supplies of Ready to Use Therapeutic Food (RUTF), feeling of improvement or worsening of the state of health, recourse to traditional medicine, and ignorance of undernutrition are also associated with this issue. Conclusion: This study highlighted barriers to the abandonment of nutritional recovery among parents of severely malnourished children aged 6 to 59 months in the health district of Titao, Burkina Faso. It is more important to consider these different factors when evaluating care protocols so that policies to reduce child undernutrition can considerably impact the targets. 展开更多
关键词 Nutritional Recovery Severe Acute Malnutrition Environmental Factors Therapeutic Factors abandonment Burkina Faso
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Abandonment and Recovery Operation of Steel Lazy-Wave Riser in Deepwater by Controlled Vessel and Cable Velocity Rate
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作者 GU Ji-jun HUANG Jun +3 位作者 GAO Lei CHEN Lei-lei JIA Ji-chuan WANG Shu-jiang 《China Ocean Engineering》 SCIE EI CSCD 2023年第1期29-41,共13页
Evaluation of abandonment and recovery operation of steel lazy-wave riser in deepwater is presented in this paper.The calculation procedure includes two single continuous SLWR and cable segments, which are coupled tog... Evaluation of abandonment and recovery operation of steel lazy-wave riser in deepwater is presented in this paper.The calculation procedure includes two single continuous SLWR and cable segments, which are coupled together to form the overall mathematical model. Then the equilibrium equations of SLWR and cable are established based on minimum total potential energy principle. The coupled equations are discretized by the finite difference method and solved by Newton-Raphson technique in an iterative manner. The present method is validated by well-established commercial code OrcaFlex. Recovery methods by considering different ratios of vessel’s moving velocity to cable’s recovery velocity are evaluated to optimize the abandonment and recovery operation. In order to keep the tension more stable during the recovery process, the rate ratio before leaving the seabed is increased, and the rate ratio after leaving the seabed is reduced. 展开更多
关键词 steel lazy-wave riser abandonment RECOVERY
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Research on pumped storage and complementary energy development models for abandoned mines in China
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作者 YANG Ke LYU Xin +3 位作者 XU Chao-shui FANG Jue-jing DUAN Min-ke ZHANG Zhai-nan 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2860-2871,共12页
Within the framework of achieving carbon neutrality,various industries are confronted with fresh challenges.The ongoing process of downsizing coal industry operations has evolved into a new phase,with the burgeoning p... Within the framework of achieving carbon neutrality,various industries are confronted with fresh challenges.The ongoing process of downsizing coal industry operations has evolved into a new phase,with the burgeoning proliferation of abandoned mines posing a persistent issue.Addressing the challenges and opportunities presented by these abandoned mines,this paper advocates for a scientific approach centered on the advancement of pumped storage energy alongside gas-oil complementary energy.Leveraging abandoned mine tunnels to establish pumped storage power stations holds significant ecological and economic importance for repurposing these sites.This initiative not only serves as an effective means to restore the ecological balance in mining regions but also provides an environmentally friendly approach to repurposing abandoned mine tunnels,offering a blueprint for economically viable pumped storage power stations.This article delineates five crucial scientific considerations and outlines seven primary models for the utilization of abandoned mine sites,delineating a novel,comprehensive pathway for energy and power development that emphasizes multi-energy complementarity and synergistic optimization within abandoned mines. 展开更多
关键词 abandoned mines pumped storage underground reservoir energy systems carbon neutrality
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Evaluation of development potential of pumped hydroelectric storage and geothermal utilization system in abandoned coal mine
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作者 WANG Meng GUO Ping-ye +3 位作者 JIN Xin DANG Guan-jie GUO Yi-chen LI Yi 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2872-2890,共19页
Every year in China,a significant number of mines are closed or abandoned.The pumped hydroelectric storage(PHS)and geothermal utilization are vital means to efficiently repurpose resources in abandoned mine.In this wo... Every year in China,a significant number of mines are closed or abandoned.The pumped hydroelectric storage(PHS)and geothermal utilization are vital means to efficiently repurpose resources in abandoned mine.In this work,the development potentials of the PHS and geothermal utilization systems were evaluated.Considering the geological conditions and meteorological data available of Jiahe abandoned mine,a simple evaluation model for PHS and geothermal utilization was established.The average efficiency of the PHS system exceeds 70%and the regulatable energy of a unit volume is over 1.53 kW·h/m^(3).The PHS system achieves optimal performance when the wind/solar power ratio reaches 0.6 and 0.3 in daily and year scale,respectively.In the geothermal utilization system,the outlet temperature and heat production are significantly affected by the injection flow rate.The heat production performance is more stable at lower rate flow,and the proportion of heat production is higher in the initial stage at greater flow rate.As the operating time increases,the proportion of heat production gradually decreases.The cyclic heat storage status has obvious advantages in heat generation and cooling.Furthermore,the energy-saving and emission reduction benefits of PHS and geothermal utilization systems were calculated. 展开更多
关键词 abandoned mine underground reservoir wind/solar energy pumped hydroelectric storage GEOTHERMAL
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Feature extraction and analysis of reclaimed vegetation in ecological restoration area of abandoned mines based on hyperspectral remote sensing images
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作者 MAO Zhengjun WANG Munan +3 位作者 CHU Jiwei SUN Jiewen LIANG Wei YU Haiyong 《Journal of Arid Land》 SCIE CSCD 2024年第10期1409-1425,共17页
The vegetation growth status largely represents the ecosystem function and environmental quality.Hyperspectral remote sensing data can effectively eliminate the effects of surface spectral reflectance and atmospheric ... The vegetation growth status largely represents the ecosystem function and environmental quality.Hyperspectral remote sensing data can effectively eliminate the effects of surface spectral reflectance and atmospheric scattering and directly reflect the vegetation parameter information.In this study,the abandoned mining area in the Helan Mountains,China was taken as the study area.Based on hyperspectral remote sensing images of Zhuhai No.1 hyperspectral satellite,we used the pixel dichotomy model,which was constructed using the normalized difference vegetation index(NDVI),to estimate the vegetation coverage of the study area,and evaluated the vegetation growth status by five vegetation indices(NDVI,ratio vegetation index(RVI),photochemical vegetation index(PVI),red-green ratio index(RGI),and anthocyanin reflectance index 1(ARI1)).According to the results,the reclaimed vegetation growth status in the study area can be divided into four levels(unhealthy,low healthy,healthy,and very healthy).The overall vegetation growth status in the study area was generally at low healthy level,indicating that the vegetation growth status in the study area was not good due to short-time period restoration and harsh damaged environment such as high and steep rock slopes.Furthermore,the unhealthy areas were mainly located in Dawukougou where abandoned mines were concentrated,indicating that the original mining activities have had a large effect on vegetation ecology.After ecological restoration of abandoned mines,the vegetation coverage in the study area has increased to a certain extent,but the amplitude was not large.The situation of vegetation coverage in the northern part of the study area was worse than that in the southern part,due to abandoned mines mainly concentrating in the northern part of the Helan Mountains.The combination of hyperspectral remote sensing data and vegetation indices can comprehensively extract the characteristics of vegetation,accurately analyze the plant growth status,and provide technical support for vegetation health evaluation. 展开更多
关键词 hyperspectral remote sensing abandoned mine ecological restoration vegetation growth status vegetation index vegetation coverage
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Design Strategies for Landscape Transformation of Abandoned Railways in Urban Centers
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作者 WU Jia 《Journal of Landscape Research》 2024年第5期41-45,共5页
The railways have significantly contributed to the economic development of the city.However,with the evolution of the city and adjustments in the industrial structure,the relocation and rerouting of major railway trun... The railways have significantly contributed to the economic development of the city.However,with the evolution of the city and adjustments in the industrial structure,the relocation and rerouting of major railway trunk lines have resulted in the abandonment of numerous urban railways.The abandoned railways,resulting from inadequate management,have transformed into sites for waste disposal and are particularly vulnerable to environmental issues,including land pollution,degradation of vegetation cover,and a decline in ecological diversity.Abandoned railways in urban centers significantly hinder transportation connectivity and adversely influence the aesthetic appeal of the city.The landscape transformation of these abandoned railways is of paramount importance in the context of urban renewal.These railway sites possess significant potential for stock utilization as specialized,underutilized spaces.Through the processes of re-planning,integration,and renewal,previously underutilized spaces can be revitalized and incorporated into the urban landscape in innovative ways.This approach not only enhances the availability of green leisure areas for residents but also contributes to the realization of sustainable urban development. 展开更多
关键词 Urban center Transformation of abandoned railway abandoned railway landscape
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A resilience-based approach in managing the closure and abandonment of large mine tailing ponds 被引量:4
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作者 Dragan Komljenovic Lazar Stojanovic +1 位作者 Vladimir Malbasic Aleksandar Lukic 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第5期737-746,共10页
Mining tailing ponds are large infrastructure objects whose life cycle spans over several decades.They are indispensable for certain types of mines where technological process produces and rejects mud.They also have p... Mining tailing ponds are large infrastructure objects whose life cycle spans over several decades.They are indispensable for certain types of mines where technological process produces and rejects mud.They also have potential to generate risks for human life,property and environment.For that reason,it is essential to adequately manage them throughout all the stages of their life cycle.The phase of their closure and abandonment is less studied and understood.The paper proposes a holistic resilience-based approach for analyzing this phase of their life cycle.The proposed methodology is validated through a case study at an actual surface iron ore mine in Bosnia and Herzegovina. 展开更多
关键词 Mine tailing ponds CLOSURE abandonment RESILIENCE RISKS UNCERTAINTIES Complexity
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An Empirical Study of Farmers' Perception and Behavior on Farmland Abandonment in Yunnan Province 被引量:1
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作者 Liyong YANG 《Asian Agricultural Research》 2017年第5期63-65,共3页
In this study,using the PRA method,we conduct a questionnaire survey on 525 farmers in 10 typical villages in Yunnan Province,and study the farmers' farmland abandonment behavior as well as their perception. Studi... In this study,using the PRA method,we conduct a questionnaire survey on 525 farmers in 10 typical villages in Yunnan Province,and study the farmers' farmland abandonment behavior as well as their perception. Studies have shown that there are some common problems for the villages in the inner suburbs and the villages in the outer suburbs such as small scale of rural land,dispersed plots and land fragmentation,and the scale and fragmentation problems are more prominent in the villages in the inner suburbs while the dispersed plot problems are more obvious in the villages in the outer suburbs; the levels of farmland abandonment vary in different sample villages,the farmland abandonment is more prevalent in the villages in the outer suburbs,the abandonment behavior involves more farmers,and farmers tend to abandon small plots of farmland; the proportion of the abandoned farmland perceived by the farmers in the villages in the inner and outer suburbs( especially in the inner suburbs) is significantly lower than the actual proportion,and farmers' perception greatly deviates from the actual reality; some farmers have wrong perception of farmland abandonment behavior,and even if there are farmers with correct perception,they also abandon farmland. 展开更多
关键词 Farmland abandonment FARMERS PERCEPTION BEHAVIOR PRA
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Modelling Regional Land Change Scenarios to Assess Land Abandonment and Reforestation Dynamics in the Pyrenees(France) 被引量:3
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作者 Laure A.VACQUIE Thomas HOUET +2 位作者 Terry L.SOHL Ryan REKER Kristi L.SAYLER 《Journal of Mountain Science》 SCIE CSCD 2015年第4期905-920,共16页
Over the last decades and centuries,European mountain landscapes have experienced substantial transformations.Natural and anthropogenic LULC changes(land use and land cover changes), especially agro-pastoral activitie... Over the last decades and centuries,European mountain landscapes have experienced substantial transformations.Natural and anthropogenic LULC changes(land use and land cover changes), especially agro-pastoral activities,have directly influenced the spatial organization and composition of European mountain landscapes.For the past sixty years, natural reforestation has been occurring due to a decline in both agricultural production activities and rural population.Stakeholders, to better anticipate future changes,need spatially and temporally explicit models to identify areas at risk of land change and possible abandonment.This paper presents an integrated approach combining forecasting scenarios and a LULC changes simulation model to assess where LULC changes may occur in the Pyrenees Mountains,based on historical LULC trends and a range of future socio-economic drivers.The proposed methodologyconsiders local specificities of the Pyrenean valleys,sub-regional climate and topographical properties,and regional economic policies.Results indicate that some regions are projected to face strong abandonment, regardless of the scenario conditions.Overall, high rates of change are associated with administrative regions where land productivity is highly dependent on socio-economic drivers and climatic and environmental conditions limit intensive(agricultural and/or pastoral) production and profitability.The combination of the results for the four scenarios allows assessments of where encroachment(e.g.colonization by shrublands) and reforestation are the most probable.This assessment intends to provide insight into the potential future development of the Pyrenees to help identify areas that are the most sensitive to change and to guide decision makers to help their management decisions. 展开更多
关键词 PYRENEES Land use change Land cover change Land abandonment Mountain landscapeReforestation LULC Model
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Spatial patterns of farmland abandonment and its impact factors in the central Three Gorges Reservoir Area 被引量:6
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作者 CHEN Ying-feng WANG Yu-kuan +2 位作者 FU Bin WANG Hai-wen WANG Wei 《Journal of Mountain Science》 SCIE CSCD 2018年第3期631-644,共14页
The severe farmland abandonment phenomena in China have tremendously decreased the farmland usage efficiency and caused a series of profound ecological and social outcomes. The complexity of farmland abandonment neces... The severe farmland abandonment phenomena in China have tremendously decreased the farmland usage efficiency and caused a series of profound ecological and social outcomes. The complexity of farmland abandonment necessitates a systematic research on its patterns and impact factors to underpin the dynamics of problem as well as potential solutions. This paper took Wanzhou district in the central part of Three Gorges Reservoir Area as an example to study the spatial distribution patterns of abandoned farmland at three scales, i.e., town, village, and plot, and analyzed the influence from labor transfer and farmland circulation. We conducted a survey on the distribution patterns of abandoned farmland via questionnaires at town and village scales, together with the modeling and interpretation of high-resolution aerial images taken by unmanned aerial vehicles at plot scale. Our research discloses a strong relationship between the distribution of abandoned farmland and the distance from population center at different scales. At eithertown or village scale, the abandonment proportion was recognized the highest in mid-distance areas and lowest in close-distance areas, and the per capita area of abandoned farmland increased with the distance to downtown or township. At plot scale, abandonment proportion presented exponential growth with the distance to village center, whereas the abandoned farmland was mainly distributed in the areas with distance above 500 m from the village center. Moreover, we noticed that labor transfer and farmland circulation are two important factors that influence farmland abandonment. Labor's outbound transfer distance has a positive linkage with the possibility of farmland abandonment. Finally, it is recommended that development and adoption of corresponding policies on local urbanization and farmland circulation will facilitate to alleviate farmland abandonment. 展开更多
关键词 Three Gorges Reservoir Area Farmland abandonment Spatial distribution pattern Labor transfer Cultivated farmland MULTI-SCALE Unmanned aerial vehicle
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Spatial pattern and mechanisms of farmland abandonment in Agricultural and Pastoral Areas of Qingzang Plateau 被引量:2
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作者 Yuling Li Tao Zhou +3 位作者 Guanghui Jiang Guangyong Li Dingyang Zhou Yu Luo 《Geography and Sustainability》 2021年第3期139-150,共12页
With the rapid development of social economy and urban−rural integration,the phenomenon of farmland aban-donment worldwide has proved to be one of the main trends of land use and land cover change(LUCC),and profoundly... With the rapid development of social economy and urban−rural integration,the phenomenon of farmland aban-donment worldwide has proved to be one of the main trends of land use and land cover change(LUCC),and profoundly affected the rural landscape and regional ecological environment.Restricted by the natural environ-ment,economic development and backward agricultural technology,the phenomenon of farmland abandonment is also common in the Qingzang Plateau(QP).Therefore,this paper adopted the spatial autocorrelation method to analyze the spatial pattern of abandonment in the agricultural and pastoral areas of the Qingzang Plateau(APA−QP)in 2017,and the geographically weighted regression(GWR)model to explore the effects of geograph-ical resources,socio-economic development and location conditions on farmland abandonment.This study found that:1)From 2015 to 2017,the abandoned farmland area in the APA−QP was approximately 18.23×10^(4)ha,with an overall abandonment rate of 15.18%.On the whole,it showed the distribution characteristics of“strong in the south and weak in the north,strong in the east and weak in the west”.2)There were positive spatial correlation between both abandoned area and abandonment rate in the APA−QP,showing“concave”and“convex”patterns,respectively,mainly concentrated in the Huang−shui Valley and the Southeast Tibet;while in the western and northern regions,the degree of abandonment was relatively low.3)Farmland abandonment in the APA−QP was mainly driven by the geographical environment changes and farmers’decision−making on farmland utilization.There was significant spatial heterogeneity on farmland abandonment associated with the impact of geographical resources,socio−economics and location conditions.The geographical resource factors had a positive impact on the abandonment,and were strongly constrained by natural geographic conditions such as altitude and slope.The farmland resources in the Qingzang Plateau are limited,but are of strategic significance for the sustainable development of agriculture in the whole Qingzang Plateau.In order to realize the rational distribution of agricul-ture and animal husbandry and the sustainable utilization of farmland resources in the plateau region,land use strategies should be implemented according to regional differences and regional advantages in order to ensure the ecological environment security of Qingzang Plateau. 展开更多
关键词 Farmland abandonment Spatial pattern Formation mechanism Geographically weighted regression Qingzang Plateau Agricultural and pastoral areas
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Intraregional Agricultural Characteristics Critical in Explaining Farmland Abandonment:Evidence from Chugoku and Shikoku Region of Japan 被引量:1
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作者 SU Guandong TOMOZAWA Kazuo +1 位作者 OKAHASHI Hidenori CHEN Lin 《Chinese Geographical Science》 SCIE CSCD 2020年第6期1111-1128,共18页
Since the 1980 s,Japan has witnessed an unprecedented decline in agriculture chiefly due to farmers’aging,depopulation,and unfavorable socio-economic conditions.This development has resulted in an increase of farmlan... Since the 1980 s,Japan has witnessed an unprecedented decline in agriculture chiefly due to farmers’aging,depopulation,and unfavorable socio-economic conditions.This development has resulted in an increase of farmland abandonment(FLA)across the country.However,it remains unclear as to how and to what extent FLA is influenced by intraregional agricultural characteristics.As such,this article discusses the issue of FLA by taking a closer look at the Chugoku and Shikoku region,as it has experienced the highest FLA rates in Japan in recent years.For this analysis,a total of 25 indicators retrieved from the census of agriculture and forestry at the former municipalities scale were selected to describe intraregional agricultural characteristics.We employed principal component analysis(PCA)to evaluate agricultural characteristics,while multiple linear regressions(MLR)was applied to explore their correlations with FLA and spatial variations.First,there are strong intraregional differences in the agricultural characteristics across the Chugoku and Shikoku region,with eight different principle components(PCs)describing their characteristics.Second,variables measuring agricultural characteristics explain nearly 52.8%of the variation in FLA in our sample.The sales orientation and scale of agriculture have the strongest negative correlation to FLA in the region,while the status of agricultural succession displays the strongest positive correlation to FLA.Third,in areas where agriculture is more stable and easier to maintain,FLA is more strongly influenced by changes in agricultural characteristics than by geographical variations.We argue that localized approaches and policies for future management need to take intraregional differences in agricultural characteristics and FLA into account.Our findings help to explain spatial variations in agricultural characteristics and FLA in regional contexts,suggesting the need for better-informed farmland use policies to mitigate further abandonment. 展开更多
关键词 intraregional agricultural characteristics farmland abandonment(FLA) Chugoku and Shikoku region Japan
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Prospects for the transformation and development of carbon storage in abandoned mines of coal enterprises from the perspective ofcarbon neutrality 被引量:5
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作者 Xin Lyu Tong Zhang +1 位作者 Liang Yuan Juejing Fang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第3期24-40,共17页
Under the carbon neutrality goal,coal enterprises must seek breakthroughs from abandoned mines,develop new resources in the new era,turn problems into countermeasures,and participate in the carbon emissions market,for... Under the carbon neutrality goal,coal enterprises must seek breakthroughs from abandoned mines,develop new resources in the new era,turn problems into countermeasures,and participate in the carbon emissions market,for contributing to the accomplishment of the national strategic goal of carbon neutrality.To this end,we investigated the relevant national policies and regulations to clarify the boundaries disclosed by the carbon information of enterprises,understood the development direction of carbon storage in abandoned mines,and clarified the transformation and development of carbon storage in aban-doned mines.We made a few suggestions:(1)China should learn from its past experience and other countries to develop the energy industry with Chinese characteristics and reform the economic system.(2)Coal enterprises must actively respond to the national carbon information disclosure policy,clarify their own responsibilities and carbon emission boundaries.(3)It is necessary to proactively obtain advanced knowledge and plan carbon storage pathways for abandoned mines.(4)Devel-opment problems of coal enterprises should be deduced using cases.The'dual carbon'goals should be achieved steadily step-by-step.(5)Three measures,i.e.improving the existing resource structure,coordinating the information of abandoned mines,and promoting the cultivation of scientific and technological talents. 展开更多
关键词 Mining engineering abandoned mines Carbon neutrality Carbon emission rights Carbon tax
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Effect of mechanical vibration process parameters on the cement plugs properties for abandoned wells 被引量:1
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作者 Hang-Ming Liu Yang-Ye He +6 位作者 Ji-Fang Wan Lin Chen Xian-Zhong Yi Yuan-Hua Zhou Yu-Xian He Xiang-Gui Ming Lu Ren 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2428-2441,共14页
A high-quality plug of the abandoned wellbore is considered an essential technical aspect of the oil and gas well abandonment technology system. This paper presents a method of active mechanical excitation to enhance ... A high-quality plug of the abandoned wellbore is considered an essential technical aspect of the oil and gas well abandonment technology system. This paper presents a method of active mechanical excitation to enhance the quality of wellbore plug barriers. An indoor simulation platform is developed, and the effects of different combinations of vibration frequency, amplitude and duration on the properties of the wellbore plug cement material are investigated. It is observed that the optimal combination of excitation parameters occurs at a vibration frequency of 15 Hz, a vibration time of 6 min, and a vibration amplitude of 3 mm. Compared with the condition without the vibration process, the cementing strength, compressive strength, and tensile strength of wellbore cement plug with the optimal mechanical vibration process could increase by 51%, 38% and 20%, respectively, while the porosity decreases by 5%. As determined by scanning electron microscopy of the set cement's microstructure, mechanical vibration effectively eliminates internal porosity and improves the set cement's density. The optimal excitation parameters obtained from the test can guide the design of the vibration plugging tool. The designed vibration plugging tool is simulated in the near field. The cement plug cementation quality tester tests the vibrating and non-vibrating samples, and the cementation ratio is calculated. The test results show that the average cementation ratio of vibrating samples is 0.89375, and that of non-vibrating samples is 0.70625, and the cementation quality is improved by 27%. It is concluded that it not only provides essential data for the design of mechanical vibration plug apparatus, on-site vibration plugs, and the development of operational specifications for vibration plugs, but also provides solid engineering guidance. 展开更多
关键词 Plugging and abandonment Cement plug VIBRATION Mechanical properties MICROSTRUCTURE
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Carbon Accumulation in a Humid Temperate Prairie Pasture Following Abandonment and Afforestation 被引量:1
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作者 J. D. White B. R. Moore 《Journal of Agricultural Science and Technology》 2010年第5期1-9,共9页
Carbon budget changes were measured on a farm near Robinson, Texas, where land originally tilled for hay production was abandoned over time periods of 10, 20, and 35 years followed by succession of prairie and forest ... Carbon budget changes were measured on a farm near Robinson, Texas, where land originally tilled for hay production was abandoned over time periods of 10, 20, and 35 years followed by succession of prairie and forest vegetation. Woody biomass accumulation increased following abandonment from 0.14 kg C m2 yr~ during forest initiation to 0.57 kg C m2 yr-1 of the mature forest Soil carbon was highest in the tilled field ( 15.77 kg C m2) with lowest in the grassland ( 11.66 kg C m-2). Soil nitrogen was highest in the tilled field (0.55 kg N ms) and lowest in the forest transition (0.38 kg N m2). Soil C:N ratios were highest in the forest transition (C:N=36) and lowest in the grassland (C:N=22). Soil respiration was constant across the site with an annual average value of 1.46 kg CO2-C m-2 yr-. Results show that land in this region may be a source of carbon for several decades following abandonment due to enhanced soil carbon emissions as a function of nutrient input shifts. 展开更多
关键词 Carbon accumulation pasture abandonment AFFORESTATION landuse change.
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Hydraulic Testing of Compacted Bentonite Used for Plug and Abandonment Operations
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作者 Heinz-Gerd Holl 《Journal of Minerals and Materials Characterization and Engineering》 2019年第5期261-278,共18页
The University of Queensland Centre for Coal Seam Gas (UQ CCSG) has investigated plugging wells with bentonite through laboratory experiments and with field trials. This paper presents the laboratory tests, which were... The University of Queensland Centre for Coal Seam Gas (UQ CCSG) has investigated plugging wells with bentonite through laboratory experiments and with field trials. This paper presents the laboratory tests, which were used to investigate the stability range of plugged sections for later well plug and abandonment operation designs. The plugs were tested on a specially built well simulator facility at The University of Queensland (UQ), School of Chemical Engineering. The bentonite material used for the plug production was treated with water and 1 weight% polyvinylpyrrolidone (PVP) which acted as a binder to allow the bentonite to be pressed into a cylindrical shape suitable for dropping into vertical wells. The experiments have shown that the best performing plug/casing size combination is able to hold pressure gradients of up to 5.9 bar/m (25.9 psi/ft) after 296 days of hydration before failing. Open hole simulations on the testing facility showed surprisingly high failure pressure gradients of 21.1 bar/m (93.3 psi/ft) after 146 days of hydration. The findings of this research indicate that the use of compressed bentonite is a viable method for sealing wells, whether they can be coal seam gas wells, conventional oil and gas wells, water wells, or coal exploration wells. 展开更多
关键词 BENTONITE Plugs HYDRAULIC Testing FAILURE Pressure Prediction WELL abandonment
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Evaluating the Spatial Uncertainty of Future Land Abandonment in a Mountain Valley(Vicdessos, Pyrenees-France): Insights from Model Parameterization and Experiments
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作者 Thomas Houet Laure Vacquié David Sheeren 《Journal of Mountain Science》 SCIE CSCD 2015年第5期1095-1112,共18页
European mountains are particularly sensitive to climatic disruptions and land use changes.The latter leads to high rates of natural reforestation over the last 50 years. Faced with the challenge of predicting possibl... European mountains are particularly sensitive to climatic disruptions and land use changes.The latter leads to high rates of natural reforestation over the last 50 years. Faced with the challenge of predicting possible impacts on ecosystem services,LUCC models offer new opportunities for land managers to adapt or mitigate their strategies.Assessing the spatial uncertainty of future LUCC is crucial for the definition of sustainable land use strategies. However, the sources of uncertainty may differ, including the input parameters, the model itself, and the wide range of possible futures. The aim of this paper is to propose a method to assess the probability of occurrence of future LUCC that combines the inherent uncertainty of model parameterization and the ensemble uncertainty of the future based scenarios. For this purpose, we used the Land Change Modeler tool to simulate future LUCC on a study site located in the Pyrenees Mountains(France) and two scenarios illustrating two land use strategies. The model was parameterized with the same driving factors used for its calibration. The definition of ‘static vs. dynamic' and ‘quantitative vs.qualitative(discretized)' driving factors, and their combination resulted in four parameterizations. The combination of model outcomes produced maps of the spatial uncertainty of future LUCC. This work involves adapting the definition of spatial uncertainty in the literature to future-based LUCC studies. It goes beyond the uncertainty of simulation models by integrating the uncertainty of the future to provide maps to help decision makers and land managers. 展开更多
关键词 Land use Land cover SCENARIO Model Mountainous reforestation Land abandonment Landmanagement
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Observation-Oriented Causal Discovery for Cultivation Abandonment of Rice Terraces: Focusing on an Effect of Cultural Endemism on Decision-Making in Toraja, Indonesia
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作者 Ayako Oide Osamu Kozan +1 位作者 Tomoko Doko Wenbo Chen 《Agricultural Sciences》 2016年第2期100-113,共14页
Previous discussion about the factors of the expanding trend of abandoned cultivation had focused only on universal factors and lacked evaluation of the regionality of the phenomenon. This paper demonstrated the Toraj... Previous discussion about the factors of the expanding trend of abandoned cultivation had focused only on universal factors and lacked evaluation of the regionality of the phenomenon. This paper demonstrated the Toraja’s regional characteristics and the influence of cultural endemism on decision-making about abandoning cultivation by an observation-oriented approach. Based on a causal framework constructed by field observation and geospatial data generation, an adjustment for overt covariates using the multivariate logistic regression model to draw the causal effect from hidden covariates was examined in two rice terraces with different water systems, i.e. irrigated field and rain-fed field. The result of sub-group analysis revealed that decisions about abandoning cultivation in Toraja were greatly associated with disadvantageous factors for intensive farming, i.e. “number of adjacent fields” and “soil erosion” rather than advantageous factors, i.e. “area of field” and “distance to roads”. Moreover, the result of interaction analysis which controlled the effect of topography revealed the powerful effect of particular decision factors only in rain-fed rice terrace: the “distance to roads” factor’s fairly negative contribution on abandoning cultivation (Odds ratio = 9.94E - 01, P value = 2.03E - 11), as well as the “number of adjacent field” factor’s positive contribution on abandoning cultivation (Odds ratio = 1.13E+00, P value = 3.65E - 04). Given the evidence from the explanation of these results by customary laws and land inheritance system for each site, therefore, it could be concluded that the screening and detection of cultural endemism’s influence was achieved using the algorithm this paper proposes. 展开更多
关键词 Cultivation abandonment DECISION-MAKING Rice Terrace Observation-Oriented Multivariate Logistic Regression Sub-Group Interaction InSAR Soil Erosion GIS
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Empirical Analysis on the Peasants' Cultivated Land Abandonment Decision-making Behaviors in Central China and the Subjective Factors of the Peasants --Jiangxi Province Is Taken as an Example
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作者 Qi CHENG Zhuhui LI Yaohui WANG Jianghua WU 《International Journal of Technology Management》 2013年第5期19-23,共5页
Following China's rapid advance the process of industrialization and urbanization, a large number of rural labor into cities, abandoned land becomes a universal phenomenon and shows an enlarge spread trend. Therefore... Following China's rapid advance the process of industrialization and urbanization, a large number of rural labor into cities, abandoned land becomes a universal phenomenon and shows an enlarge spread trend. Therefore, the food security of our country is threatened. This article will according to the farmers' angle of view, from the farmers owned their own labor, land and capital three aspects, uses field survey data to analyze the relationship between the situation of human capital, employment policy, farmland status and management decision, income and investment decision-making this five aspects and land reclamation. The result shows that age, education, arable area, whether the land transfer, engaged in non-agricultural sector employment time, work area, per capita income, non-agricultural income and investment has a significant impact on arable land abandonment, and reflect the development potential of the family of peasants and a tendency of development having a positive correlation with arable land abandonment, this phenomenon reflects in our nation, the rural residents are divorced from the original rural living environment and integrate into cities, a gradual process of get rid of the original way of life in the new way. 展开更多
关键词 Arable Land abandonment PEASANT Empirical Analysis
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Characteristics and driving factors of abandoned cultivated land in the hilly regions of southern China:A case study in Longnan,Jiangxi Province
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作者 CHEN Ze-bin CHEN Yong-lin +4 位作者 LI Chao-jun LIN Jian-ping CHEN Pei-ru SUN Wei-wei WAN Zhi-wei 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1483-1498,共16页
The abandonment of cultivated land in southern China was gradually obvious.This research aims to provide a reference for solving the abandonment of cultivated land in hilly regions and promote rural development in Chi... The abandonment of cultivated land in southern China was gradually obvious.This research aims to provide a reference for solving the abandonment of cultivated land in hilly regions and promote rural development in China.We examined Longnan county located in the hilly regions of southern China as an example,where abandoned cultivated land is very common.We analyzed its land use data with a field survey to identify the abandoned cultivated land and geospatial characteristics.From the two aspects of social and natural factors,we analyzed the factors driving cultivated land abandonment with the help of Geodetector.The results showed that in 2019,the total area of the abandoned cultivated land in Longnan county was 4,962.35 hm^(2),covering 39.51% of this region.Among the topographic factors,the abandonment rate is positively correlated with elevation and slope gradient,but not with slope direction.Among the land parcel conditions,the abandonment rate is positively correlated with the access to road network and cultivation distance from settlement.At the county level,the abandonment of cultivated land in study area was affected by multiple factors,among which,the direct factor was the reduction in the labor force,such as the decrease of farming laborers and the increase of female population,which made farming unsustainable.Changes in production factors also promoted transformations in farmers’motivation to engage in production,such as the decrease of grain crops and the increase of cash crops,which was the indirect factor affecting cultivated land abandonment.The development of the rural nonagricultural industry affected farmers’enthusiasm,such as the decrease of farming households,which was the fundamental factor leading to cultivated land abandonment in this area. 展开更多
关键词 Cultivated land abandonment Spatial distribution Geodetector Driving factor Hilly region County level
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