Cropland abandonment is prevalent throughout China,particularly in mountainous regions.However,the varying degrees of land marginalization and the specific factors influencing different types of cropland remain insuff...Cropland abandonment is prevalent throughout China,particularly in mountainous regions.However,the varying degrees of land marginalization and the specific factors influencing different types of cropland remain insufficiently understood.This knowledge gap hampers targeted management strategies for mitigating cropland abandonment in these areas.This study used spatial analysis,logistic regression,and random forest models to explore the spatial patterns and key drivers of abandonment across flatland,terrace,and slopeland in Chongyi county,a mountainous region in Jiangxi Province of South China,utilizing data from the 2009 and 2019 national land surveys of China.Results showed that the overall cropland abandonment rate in Chongyi county was 36.46%,with particularly high rates in core terrace conservation areas.Abandoned cropland was spatially clustered,predominantly in high-elevation regions.The abandonment rates were 9.71%for flatland,37.52%for terrace,and 43.02%for slopeland.Variations in vegetation cover on abandoned cropland suggest that abandonment started earlier on slopeland and later extended to terraces and flatlands.The factors driving the abandonment of flatland,terrace,and slopeland included land altitude,cultivation height difference,and distance to forest land,respectively.Consequently,the results recommend implementing land consolidation and developing small machinery projects for the fragmented flatland.Promoting the multifunctional use of terraces could realize their ecological value.Additionally,the Program of Converting Farmland to Forest should be implemented on the low-quality slopeland.展开更多
This study explores the impact of intergenerational differences on farmers' terrace abandonment in response to increasing intergenerational differentiation among rural households and the practical issue of terrace...This study explores the impact of intergenerational differences on farmers' terrace abandonment in response to increasing intergenerational differentiation among rural households and the practical issue of terrace abandonment. Logit and Tobit models are employed to conduct empirical analysis and it is found that terrace abandonment increases sequentially among the new, middle, and old generations, confirming that intergenerational differences significantly influence whether farmers abandon terraces and the terrace abandonment scale. Village characteristics and government subsidies significantly influence farmers' terrace abandonment. An increase in the number of migrant workers in the village increases terrace abandonment among new and middle generation farmers, whereas an increase in the distance from the village to the county significantly increases terrace abandonment among old generation farmers. An increase in the village's total population significantly reduces terrace abandonment among new generation farmers. An increase in government subsidies significantly reduces terrace abandonment among middle and old generation farmers. The impact of intergenerational differences on terrace abandonment is more pronounced in low-altitude areas. To reduce terrace abandonment, it is necessary to promote terrace transfer, develop characteristic agriculture, improve terrace farming subsidies, and propose targeted strategies for the different generations of farmers.展开更多
Since the 1950s, noteworthy farmland abandonment has been occurring in many developed countries and some developing countries. This global land use phenomenon has fundamentally altered extensive rural landscapes. A re...Since the 1950s, noteworthy farmland abandonment has been occurring in many developed countries and some developing countries. This global land use phenomenon has fundamentally altered extensive rural landscapes. A review of global farmland abandonment under the headings of ＂land use change - driving mechanisms - impacts and consequences - policy responses＂ found the following： （1） Farmland abandonment has occurred primarily in developed countries in Europe and North America, but the extent of abandonment has varied significantly. （2） Changing socio-economic factors were the primary driving forces for the farmland abandonment. And land marginalization was the fundamental cause, which was due to the drastic increase of farming opportunity cost, while the direct factor for abandonment was the shrink of agricultural labor forces. （3） Whether to abandon, to what extent and its spatial distributions were finally dependent on integrated effect from the physical conditions, laborer attributes, farming and regional socio-economic conditions at the village, household and parcel scales. With the exception of Eastern Europe, farmland abandonment was more likely to occur in mountainous and hilly areas, due to their unfavorable farming conditions. （4） A study of farmland abandonment should focus on its ecological and environmental effects, while which is more positive or more negative are still in dispute. （5） Increasing agricultural subsidies will be conductive to slowing the rate of farmland abandonment, but this is not the only measure that needs to be implemented. Due to China＇s rapid urbanization, there is a high probability that the rate of abandonment will increase in the near future. However, very little research has focused on this rapid land-use trend in China, and, as a result, there is an inadequate understanding of the dynamic mechanisms and consequences of this phenomenon. This paper concludes by suggesting some future directions for further research in China. These directions include monitoring regional and national abandonment dynamics, analyzing trends, assessing the risks and socio-economic effects of farmland abandonment, and informing policy making.展开更多
Farmland abandonment is a type of land use change in the mountain region,and this change is under rapid development. Whether farmland transfer can prevent this process and promote the effective allocation of land reso...Farmland abandonment is a type of land use change in the mountain region,and this change is under rapid development. Whether farmland transfer can prevent this process and promote the effective allocation of land resources or not is a question worth studying and discussion. With the help of the previous research findings,the objective of this paper was to find out the role of farmland transfer on preventing farmland abandonment,by using the methods of multiple view with two factors,and single factor correlation analysis. The results showed that:(1) At village level,a significant negative correlation between farmland transfer and farmland abandonment existed in the study site,with R2 = 0.7584. This correlation of farmland with high grade farming conditions presented more outstandingly. The fitted curve for the farmland at Level I had the largest R2 at 0.288,while that for the farmland at Level IV had the smallest R2 at 0.103. Which indicated that farmland transfer could prevent the abandonment of farmland with high grade farming conditions?(2) At plot level,the abandonment rate of farmland with high grade farming conditions was significantly lower than that of farmland with poor grade farming conditions. It was the lowest at 10.49% for the farmland with Level I farming conditions,whereas the farmland with Level I farming conditions was 26.21%. Abandoned farmland was mainly contributed by farmland with Level IV farming conditions in the study site.(3) At village level,the role of farming conditions on farmland abandonment was insignificant. The univariate correlation analysis revealed that the abandonment ratio was negatively correlated with the proportions of farmland at Levels I and II and their accumulated proportion; however,their R2 were small at 0.194,0.258,and 0.275,respectively. The abandonment of farmland with high farming conditions still existed. The abandonment ratios of farmland at Levels I and II were high at 9.96% and 10.60%,respectively. This presented that farmland transfer on behalf of the land rental market was still not developed.(4) However,the village possessed the high rate of farmland transfer,and its rate of farmland abandonment with high grade farming conditions was all lower. When the transfer ratios of farmland were over 20%,the abandonment ratios of farmland at Levels I and II were 6.47% and 6.92%,respectively. Farmland abandonment was still controlled by the improvement of land rental market. And the functions of land rental market optimizing the utilization of farmland resources have been presented to a certain degree.(5) To further improve the marketing degree of land rental,the probability of farmland abandonment could be reduced. Especially,their function to farmland with high grade farming conditions was very obvious,and could avoid the waste of farmland resources with high grade farming conditions.展开更多
Driven by urbanization and industrialization,arable land in hilly and mountainous regions of China is gradually becoming marginalized,with the extent of arable land abandonment rapidly expanding from poor-quality slop...Driven by urbanization and industrialization,arable land in hilly and mountainous regions of China is gradually becoming marginalized,with the extent of arable land abandonment rapidly expanding from poor-quality sloping arable land to high-quality terraces.The abandonment of large-scale terraces will lead to a series of socio-economic and ecological effects.A national sample survey was used to investigate the extent and spatial distribution of terrace abandonment in China,and a total of 560 valid village questionnaires from 329 counties were collected in the mountainous areas of China.The main findings are as follows:(1)The phenomenon of terrace abandonment was widespread throughout the country,with 54% of the total surveyed villages exhibiting terrace abandonment,and the area of abandoned terraces accounting for 9.79% of the total.(2) The degree of terrace abandonment is high in the south and low in the north.The most serious region with abandonment was the hilly and mountainous areas in the south,especially in the middle and lower Yangtze River region.(3)The main driving factors of terrace abandonment were rural labor migration,agricultural mechanization level,irrigation conditions,and transportation conditions for cultivation.Targeted measures should be taken based on the specific conditions of each area to alleviate terrace abandonment.Measures such as improving terrace mechanization are universally applicable.Specifically,low-quality terraces can be withdrawn orderly,and for high-quality terraces,multiple measures are needed to consolidate agricultural production,such as adjusting the planting structure,strengthening agricultural infrastructure construction,and encouraging the transfer of land-use rights as well as large-scale operation.展开更多
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
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
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
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
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
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
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
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
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
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
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
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
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
Transmission blockage caused by structural defects of small hydropower distribution network and insufficient regulation flexibility,which has a certain coupling relationship in time series,is the main reason for water...Transmission blockage caused by structural defects of small hydropower distribution network and insufficient regulation flexibility,which has a certain coupling relationship in time series,is the main reason for water abandonment.Based on the characteristics of time-sharing multiplexing of energy storage system(ESS),utilizing the coupling relationship of water abandonment events and rationally configuring ESS can solve the problems of small hydropower transmission congestion and lack of regulatory flexibility.The causes of insufficient flexibility and transmission blockage resulting in water abandonment,and the coupling relationship with ESS are analyzed.A source-grid-storage collaborative planning model for small hydropower distribution network is established.The upper-level objective is to maximize on-site consumption of small hydropower and the profits of regional small hydropower investors.The lower-level objective is to minimize average voltage offset,the input of VAR compensation system(VCS)and the number of transformer tap changer operation.The YALMIP solver is used to solve the optimization problems.Taking the 90 MW small hydropower unit in a certain area as an example,collaborative planning and operation analysis is conducted.The results prove that the proposed method can improve the on-site consumption of small hydropower,increase the income of regional small hydropower investors,and can also increase the voltage quality of the distribution network.展开更多
Farmland abandonment is a global problem and considered one of the most important areas in land use change research. Farmland abandonment research currently focuses on understanding the factors that affect farmland ab...Farmland abandonment is a global problem and considered one of the most important areas in land use change research. Farmland abandonment research currently focuses on understanding the factors that affect farmland abandonment and developing scientific models to simulate farmland abandonment. The study reviewed the natural and political factors driving farmland abandonment and summarized the main models for farmland abandonment simulation together with their advantages and disadvantages. We discuss the main ecological effects of farmland abandonment and propose farmland abandonment research directions. The study found that:(1) the influence of labor cost change and ageing labor force on farmland abandonment needs further investigation,(2) simulation models for farmland abandonment must include the decision-making mechanism of individual farmers and focus on macro large-scale abandonment prediction models, and(3) the influence of farmland abandonment on landscape culture must be investigated in detail.展开更多
基金supported by the National Natural Science Foundation of China[Grant No.42201232]the Science and Technology Research Project of Jiangxi Provincial Department of Education[Grant No.GJJ210539].
文摘Cropland abandonment is prevalent throughout China,particularly in mountainous regions.However,the varying degrees of land marginalization and the specific factors influencing different types of cropland remain insufficiently understood.This knowledge gap hampers targeted management strategies for mitigating cropland abandonment in these areas.This study used spatial analysis,logistic regression,and random forest models to explore the spatial patterns and key drivers of abandonment across flatland,terrace,and slopeland in Chongyi county,a mountainous region in Jiangxi Province of South China,utilizing data from the 2009 and 2019 national land surveys of China.Results showed that the overall cropland abandonment rate in Chongyi county was 36.46%,with particularly high rates in core terrace conservation areas.Abandoned cropland was spatially clustered,predominantly in high-elevation regions.The abandonment rates were 9.71%for flatland,37.52%for terrace,and 43.02%for slopeland.Variations in vegetation cover on abandoned cropland suggest that abandonment started earlier on slopeland and later extended to terraces and flatlands.The factors driving the abandonment of flatland,terrace,and slopeland included land altitude,cultivation height difference,and distance to forest land,respectively.Consequently,the results recommend implementing land consolidation and developing small machinery projects for the fragmented flatland.Promoting the multifunctional use of terraces could realize their ecological value.Additionally,the Program of Converting Farmland to Forest should be implemented on the low-quality slopeland.
基金Key Program of National Natural Science Foundation of China,No.41930757National Natural Science Foundation of China,No.42371285。
文摘This study explores the impact of intergenerational differences on farmers' terrace abandonment in response to increasing intergenerational differentiation among rural households and the practical issue of terrace abandonment. Logit and Tobit models are employed to conduct empirical analysis and it is found that terrace abandonment increases sequentially among the new, middle, and old generations, confirming that intergenerational differences significantly influence whether farmers abandon terraces and the terrace abandonment scale. Village characteristics and government subsidies significantly influence farmers' terrace abandonment. An increase in the number of migrant workers in the village increases terrace abandonment among new and middle generation farmers, whereas an increase in the distance from the village to the county significantly increases terrace abandonment among old generation farmers. An increase in the village's total population significantly reduces terrace abandonment among new generation farmers. An increase in government subsidies significantly reduces terrace abandonment among middle and old generation farmers. The impact of intergenerational differences on terrace abandonment is more pronounced in low-altitude areas. To reduce terrace abandonment, it is necessary to promote terrace transfer, develop characteristic agriculture, improve terrace farming subsidies, and propose targeted strategies for the different generations of farmers.
基金The NSFC-IIASA Major International Joint Research Project,No.41161140352
文摘Since the 1950s, noteworthy farmland abandonment has been occurring in many developed countries and some developing countries. This global land use phenomenon has fundamentally altered extensive rural landscapes. A review of global farmland abandonment under the headings of ＂land use change - driving mechanisms - impacts and consequences - policy responses＂ found the following： （1） Farmland abandonment has occurred primarily in developed countries in Europe and North America, but the extent of abandonment has varied significantly. （2） Changing socio-economic factors were the primary driving forces for the farmland abandonment. And land marginalization was the fundamental cause, which was due to the drastic increase of farming opportunity cost, while the direct factor for abandonment was the shrink of agricultural labor forces. （3） Whether to abandon, to what extent and its spatial distributions were finally dependent on integrated effect from the physical conditions, laborer attributes, farming and regional socio-economic conditions at the village, household and parcel scales. With the exception of Eastern Europe, farmland abandonment was more likely to occur in mountainous and hilly areas, due to their unfavorable farming conditions. （4） A study of farmland abandonment should focus on its ecological and environmental effects, while which is more positive or more negative are still in dispute. （5） Increasing agricultural subsidies will be conductive to slowing the rate of farmland abandonment, but this is not the only measure that needs to be implemented. Due to China＇s rapid urbanization, there is a high probability that the rate of abandonment will increase in the near future. However, very little research has focused on this rapid land-use trend in China, and, as a result, there is an inadequate understanding of the dynamic mechanisms and consequences of this phenomenon. This paper concludes by suggesting some future directions for further research in China. These directions include monitoring regional and national abandonment dynamics, analyzing trends, assessing the risks and socio-economic effects of farmland abandonment, and informing policy making.
基金Funds for International Cooperation and Exchange of National Natural Science Foundation of China(NSFC-IIASA Project),No.41161140352Humanity and Social Science Youth Foundation of Ministry of Education of China,No.10YJCZH122
文摘Farmland abandonment is a type of land use change in the mountain region,and this change is under rapid development. Whether farmland transfer can prevent this process and promote the effective allocation of land resources or not is a question worth studying and discussion. With the help of the previous research findings,the objective of this paper was to find out the role of farmland transfer on preventing farmland abandonment,by using the methods of multiple view with two factors,and single factor correlation analysis. The results showed that:(1) At village level,a significant negative correlation between farmland transfer and farmland abandonment existed in the study site,with R2 = 0.7584. This correlation of farmland with high grade farming conditions presented more outstandingly. The fitted curve for the farmland at Level I had the largest R2 at 0.288,while that for the farmland at Level IV had the smallest R2 at 0.103. Which indicated that farmland transfer could prevent the abandonment of farmland with high grade farming conditions?(2) At plot level,the abandonment rate of farmland with high grade farming conditions was significantly lower than that of farmland with poor grade farming conditions. It was the lowest at 10.49% for the farmland with Level I farming conditions,whereas the farmland with Level I farming conditions was 26.21%. Abandoned farmland was mainly contributed by farmland with Level IV farming conditions in the study site.(3) At village level,the role of farming conditions on farmland abandonment was insignificant. The univariate correlation analysis revealed that the abandonment ratio was negatively correlated with the proportions of farmland at Levels I and II and their accumulated proportion; however,their R2 were small at 0.194,0.258,and 0.275,respectively. The abandonment of farmland with high farming conditions still existed. The abandonment ratios of farmland at Levels I and II were high at 9.96% and 10.60%,respectively. This presented that farmland transfer on behalf of the land rental market was still not developed.(4) However,the village possessed the high rate of farmland transfer,and its rate of farmland abandonment with high grade farming conditions was all lower. When the transfer ratios of farmland were over 20%,the abandonment ratios of farmland at Levels I and II were 6.47% and 6.92%,respectively. Farmland abandonment was still controlled by the improvement of land rental market. And the functions of land rental market optimizing the utilization of farmland resources have been presented to a certain degree.(5) To further improve the marketing degree of land rental,the probability of farmland abandonment could be reduced. Especially,their function to farmland with high grade farming conditions was very obvious,and could avoid the waste of farmland resources with high grade farming conditions.
基金Key Program of National Natural Science Foundation of China,No.41930757GDAS’ Project of Science and Technology Development,No.2020GDASYL-20200104005。
文摘Driven by urbanization and industrialization,arable land in hilly and mountainous regions of China is gradually becoming marginalized,with the extent of arable land abandonment rapidly expanding from poor-quality sloping arable land to high-quality terraces.The abandonment of large-scale terraces will lead to a series of socio-economic and ecological effects.A national sample survey was used to investigate the extent and spatial distribution of terrace abandonment in China,and a total of 560 valid village questionnaires from 329 counties were collected in the mountainous areas of China.The main findings are as follows:(1)The phenomenon of terrace abandonment was widespread throughout the country,with 54% of the total surveyed villages exhibiting terrace abandonment,and the area of abandoned terraces accounting for 9.79% of the total.(2) The degree of terrace abandonment is high in the south and low in the north.The most serious region with abandonment was the hilly and mountainous areas in the south,especially in the middle and lower Yangtze River region.(3)The main driving factors of terrace abandonment were rural labor migration,agricultural mechanization level,irrigation conditions,and transportation conditions for cultivation.Targeted measures should be taken based on the specific conditions of each area to alleviate terrace abandonment.Measures such as improving terrace mechanization are universally applicable.Specifically,low-quality terraces can be withdrawn orderly,and for high-quality terraces,multiple measures are needed to consolidate agricultural production,such as adjusting the planting structure,strengthening agricultural infrastructure construction,and encouraging the transfer of land-use rights as well as large-scale operation.
基金supported by National Natural Science Foundation of China (Grant No. 41371539)Three Gorges Project Committee of the State Council research project: The ecological barrier area of Three Gorges Reservoir ecological benefits monitoring technology and assessment approach (Grant No. 0001792015CB5005)
文摘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.
文摘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.
基金supported by the MODE RESPYR project(ANR 2010 JCJC 1804-01)founded by the French National Science Agency(ANR)
文摘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.
基金This research was supported by the National Social Science Fund of China(Grant No.20&ZD090)the Second Tibetan Plateau Scientific Expedition and Research Program(Grant No.2019QZKK0405)the Na-tional Natural Science Foundation of China(Grant No.42071249,Grant No.42001199).
文摘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.
基金financially supported by the National Natural Science Foundation of China (Grant No.52271299)the Science Foundation of China University of Petroleum,Beijing (Grant No.2462020YXZZ046)。
文摘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.
基金Under the auspices of Japan Society for the Promotion of Science(JSPS)(No.18H00771,16K16956)part through the Hiroshima University TAOYAKA Program for Creating a Flexible,Enduring,Peaceful Societyfunded by the Program for Leading Graduate Schools,Ministry of Education,Culture,Sports,Science and Technology。
文摘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.
基金Supported by Supported by Program for Innovative Research Team(in Science and Technology)in University of Yunnan Province
文摘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.
文摘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.
文摘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.
基金supported the HumanEnvironment Observatory of the Haut-Vicdessos (Labex DRIIHM - OHM Haut-Vicdessos)the MODE RESPYR project (ANR 2010 JCJC 1804-01)the SAMCO Project (ANR-12-SENV-0004) founded by the French National Science Agency (ANR)
文摘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.
文摘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.
文摘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.
文摘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.
基金supported by the General Program of the National Natural Science Foundation of China(No.62176146).
文摘Transmission blockage caused by structural defects of small hydropower distribution network and insufficient regulation flexibility,which has a certain coupling relationship in time series,is the main reason for water abandonment.Based on the characteristics of time-sharing multiplexing of energy storage system(ESS),utilizing the coupling relationship of water abandonment events and rationally configuring ESS can solve the problems of small hydropower transmission congestion and lack of regulatory flexibility.The causes of insufficient flexibility and transmission blockage resulting in water abandonment,and the coupling relationship with ESS are analyzed.A source-grid-storage collaborative planning model for small hydropower distribution network is established.The upper-level objective is to maximize on-site consumption of small hydropower and the profits of regional small hydropower investors.The lower-level objective is to minimize average voltage offset,the input of VAR compensation system(VCS)and the number of transformer tap changer operation.The YALMIP solver is used to solve the optimization problems.Taking the 90 MW small hydropower unit in a certain area as an example,collaborative planning and operation analysis is conducted.The results prove that the proposed method can improve the on-site consumption of small hydropower,increase the income of regional small hydropower investors,and can also increase the voltage quality of the distribution network.
基金National Natural Science Foundation of China(41501192)The Strategic Priority Research Program of Chinese Academy of Sciences(XDA20040201)Key Laboratory of Earth Observation and Geospatial Information Science of NASG(201807)
文摘Farmland abandonment is a global problem and considered one of the most important areas in land use change research. Farmland abandonment research currently focuses on understanding the factors that affect farmland abandonment and developing scientific models to simulate farmland abandonment. The study reviewed the natural and political factors driving farmland abandonment and summarized the main models for farmland abandonment simulation together with their advantages and disadvantages. We discuss the main ecological effects of farmland abandonment and propose farmland abandonment research directions. The study found that:(1) the influence of labor cost change and ageing labor force on farmland abandonment needs further investigation,(2) simulation models for farmland abandonment must include the decision-making mechanism of individual farmers and focus on macro large-scale abandonment prediction models, and(3) the influence of farmland abandonment on landscape culture must be investigated in detail.
