China's transition from a planned economy to a market economy has resulted in many changes in its urban structure and society and provided an opportunity for a quasi-longitudinal case study on the relationship bet...China's transition from a planned economy to a market economy has resulted in many changes in its urban structure and society and provided an opportunity for a quasi-longitudinal case study on the relationship between the built environment and activity-travel behavior.This paper draws upon data from an activity diary survey conducted in Beijing in 2007.The survey sample comprised 652 residents living in Danwei(work unit),commodity housing,and affordable housing neighborhoods.On the basis of the three-dimensional geo-visualization analysis of the space-time path and statistical multivariate regression models of daily travel and leisure time,it was found that both residential spatial factors and socio-demographics influence residents' daily behaviors.The findings show that Danwei residents have less daily travel time than those who live in commodity housing,but people living in affordable housing endure the longest travel time.Daily leisure time is associated more with individual attributes.We argue that although China's transition is currently gradual,the Danwei system may continue to play significant roles in daily life,and it might provide a valuable model for neighborhood spatial planning.展开更多
Under the planned economy,China’s distribution relations were relations among the state,state-run enterprises,employees and the collective economy;relations between heavy industry and light industry;and relations bet...Under the planned economy,China’s distribution relations were relations among the state,state-run enterprises,employees and the collective economy;relations between heavy industry and light industry;and relations between cities and the countryside.After China’s transition to a market-oriented economy,the distribution relations among the state,state-run enterprises and employees evolved into distribution relations between the government,enterprises and households;the distribution relations between heavy industry and light industry evolved into distribution relations between the state sector and the private sector;and the distribution relations between cities and the countryside evolved into distribution relations between original urban dwellers and migrant populations.Wage system reform was carried out throughout the transition of these three types of distribution relations.Income distribution contradictions in China,which are a problem left over from history and intrinsic to the market-based economy,eased over the years.Some people and regions achieved prosperity,and urban-rural and interregional income gaps narrowed.However,widening household income gaps pose barriers to China’s economic sustainability and vision of building a moderately prosperous society in all respects.Mechanisms to promote common prosperity are incomplete and inadequate.The disequilibrium of functional distribution is an important cause of these income inequalities.The overall wage level of ordinary workers is low.In the future,China'should give full play to the decisive role of the market in primary distribution to ensure proper return to all types of factors,and enhance redistribution to achieve common prosperity for all its people.展开更多
Globally Important Agricultural Heritage Systems (GIAHS) is a wide program to promote the conservation and adap-tive management of such systems and their associated landscapes, biodiversity, knowledge systems and cult...Globally Important Agricultural Heritage Systems (GIAHS) is a wide program to promote the conservation and adap-tive management of such systems and their associated landscapes, biodiversity, knowledge systems and cultures. Rice-Fish Systems (RFS) in Longxian village of China, as a traditional agricultural system, was selected as one of the five pilot sites of GIAHS in 2005. Researchers have paid more attention to the dynamic conser-vation and adaptive management of RFS because it is under severe threats from global development challenges. Tourism is suggested to be brought into the RFS conservation program as an alternative industry. This paper presents a comparative study of residents in three types of farm household in Longxian, seeking attitudes to the RFS conservation and tourism development and ways in which such information may guide future strategies. Results show resi-dents, belonging to the household type in which most family mem-bers are abroad, have the most positive attitudes to RFS conserva-tion and tourism development; while residents, as other household type in which less than 50% of family members are abroad, are the least sensitive group in these three household types, due to the motivation of moving abroad weakening their enthusiasm to participate in the local activities. Implications are discussed in the context of how resident attitudes will affect the future manage-ment of GIAHS conservation and tourism development, and then measures are put forward to foster tourism cooperation and multi-stakeholders process establishment.展开更多
Quality of life(QOL) is a hotspot issue that has attracted increasing attention from the Chinese Government and scholars, it is also a vital issue that should be addressed during the cause of ′establishing overall we...Quality of life(QOL) is a hotspot issue that has attracted increasing attention from the Chinese Government and scholars, it is also a vital issue that should be addressed during the cause of ′establishing overall well-off society′. Northeast China is one of the most import old industrial bases in China, however, the industrial structure of heavy chemical industry and the development mode of ′production first, living last′ have leaded to series of social problems, which have also become a serious bottleneck to social stability and economic sustainable development. Through applying the methods of BP neural network, exploratory spatial data analysis(ESDA) and spatial regression model, this paper examines the space-time dynamics of QOL of the residents in Northeast China. We first investigate the indexes of QOL of the residents and then use ESDA methods to visualize its space-time relationship. We have found a spatial agglomeration of QOL of the residents in middle-southern Liaoning Province, central Jilin Province and Harbin-Qiqihar-Daqing area of Heilongjiang Province. Two third of the counties are low-low spatial correlation, and the correlative type of about 60% of the prefecture level areas keeps stable, indicating QOL of the residents in Northeast China shows a certain character of path dependence or spatial locked. We have also found that economic strength and development levels of service industry have positive and obvious effect on QOL of the residents, while the effect of such indexes as the social service level and the proportion of the tertiary industries are less.展开更多
The paper presents the possibilities of implementing micro-simulation traffic tools in order to develop the evacuation plans. Well elaborated evacuation plans are the basis for alleviating the consequences resulting f...The paper presents the possibilities of implementing micro-simulation traffic tools in order to develop the evacuation plans. Well elaborated evacuation plans are the basis for alleviating the consequences resulting from emergencies. The simulation tools allow the design and verification of various evacuation planning scenarios with minimisation of costs and time. The paper provides detailed presentation of the basic characteristics of microscopic simulation of traffic flows, as well as examples of their implementation worldwide. The characteristics of the software tools are described through an overview of the basic settings ofPTV VISSIM (Planung Transport Verkehrin Stadten--Simulations model) program as one of the most significant representatives of these tools. The necessity of implementing the traffic tools in evacuation results from the crucial role of traffic in reducing the consequences of emergencies. These tools allow also a detailed analysis of the output data in order to select a suitable solution. The concluding part of the paper presents an example of evacuation of the population through the Jankomir node as part of the European project "preparedness for evacuation in case of a nuclear accident". The evacuation was performed through three scenarios in circumstances of higher or lower transport demand.展开更多
During the rapid urbanization period, the contradiction between demand for the construction land and the preservation of cultivated land for food security is getting more and more serious in China. With the urbanizati...During the rapid urbanization period, the contradiction between demand for the construction land and the preservation of cultivated land for food security is getting more and more serious in China. With the urbanization the rural settlement land is increasing instead of decreasing; This paper aims at.finding the driving forces for rural settlement land expanston. Based on land use change survey data (1996-2006) by the Ministry of Land and Resources P. R. C., this paper find, that per capita area for rural settlement land is more than per capita area for city; township and industrial land in each province except Tibet. Besides, rural settlement land area and per capita rural settlement land area are increasing while the rural poputation is decreasing in most provinces. The main problems of rural settlement land use are low efficiency, high vacancy rate, chaotic layout and illegal occupancy. Then the driving forces [br rural settlement land expansion, including economic development, family income, family scale, psychological factors, urbanization, transportation, lack of planning, limited circulation of dwelling-house land and imperfect sociat security, ate explored based on above analysis, Finalty, policy recommendations, in view of different influencing factors, are put forward to control the disorder expansion of rural setttement land.展开更多
This paper studies factors influencing rural-urban labor migration in China,particularly the implementation of rural cooperative medical insurance(RCMI) in the year 2003.With the support of data analysis from the year...This paper studies factors influencing rural-urban labor migration in China,particularly the implementation of rural cooperative medical insurance(RCMI) in the year 2003.With the support of data analysis from the year 2000,2004 and 2006,clear linear correlations are found between gender,income,health condition and rural-urban labor flow,whereas the impact of education and employment status are more complicated.More importantly,results from regression show that the establishment of RCMI in countryside of China not only inhibits rural residents from seeking employment outside the village,but also pulls back rural people who have already worked in cities.When regional dimension is concerned,the pure composite effect of RCMI on rural labor flow is less significant in coastal areas with better economic performance and medical service.展开更多
The importance of social sports in urban development show that it makes the quality of urban residents greatly improved and becomes a strong surge of power to promote the development of economy; it makes the cultural ...The importance of social sports in urban development show that it makes the quality of urban residents greatly improved and becomes a strong surge of power to promote the development of economy; it makes the cultural connotations of the city more abundant and becomes the propeller of urban cultural development. And the specific roles show that it forms the group of physical and mental health in the city; it makes sports become an important part of people' s lives; it cultivates and enhances the citizens' sense of honor; it improves the urban management and enhances the image of the city.展开更多
Concentrations of PCDD/Fs, dioxin-like PCBs as well as six indicator PCBs were determined in animal origin foods collected from Hong Kong retail market during 2008-2010. The dietary intake of an average Hong Kong adul...Concentrations of PCDD/Fs, dioxin-like PCBs as well as six indicator PCBs were determined in animal origin foods collected from Hong Kong retail market during 2008-2010. The dietary intake of an average Hong Kong adult resident was estimated to be 0.806-0.833 pg WHO-TEQ kg^-1 b.w. d^-1 of dioxin-like compounds, lower than the tolerable daily intake introduced by WHO. The 95th percentile consumer were exposed by dietary at the level of 2.72 to 2.81 pg WHO-TEQ kg^-1 b.w. d^-1 or 81.6-84.3 pg WHO-TEQ kg^-1 b.w. month^-1 , higher than 70 pg WHO-TEQ kg t b.w. month^-1. DL-PCBs contributed 49.2% of total TEQ intake. The daily intake of indicator PCB was 2.83 ng kg^-1 b.w. d^-1. Approximately 2/3 of dietary intake of dioxin-like compounds came from sea food products. Ten brands of infant formula products were tested and the potential dietary intake of formula-fed infants of Hong Kong was estimated to be 1.46-1.58 pg WHO-TEQ kg^-1 b.w. d^-1 during 1st month and decreases afterwards.展开更多
Delimitation of an urban growth boundary(UGB)can effectively curb disorderly urban expansion,optimize urban development space and protect the ecological environment.Eco-environmental sensitivity was evaluated and area...Delimitation of an urban growth boundary(UGB)can effectively curb disorderly urban expansion,optimize urban development space and protect the ecological environment.Eco-environmental sensitivity was evaluated and areas prohibiting construction expansion were extracted by establishing an index system.Point of interest(POI)and microblog data were utilized to analyze the expansion of residential activity space.Urban space expansion potential was calculated using a comprehensive evaluation model,and an urban growth boundary for Jinan in 2020 was delimited combining the predicted urban expansion scale.The results showed that:(1)An evaluation of eco-environmental sensitivity can effectively protect ecological land and provide an ecological basis for urban expansion.Regions with high eco-environmental sensitivities in Jinan are located along the banks of the Yellow River and Xiaoqing River and in southeast mountainous areas,but eco-environmental sensitivities in the central,north and southeast areas are relatively low;(2)The model to evaluate urban residential activity expansion can quantify the spatial distribution of urban residents’activities.Regions with high potential for residential activity space expansion in Jinan are mainly concentrated in the middle of Jinan and most are part of existing built-up areas and surrounding areas;(3)The method that delimits urban growth boundaries based on the coordination of ecology and residential activity space is reasonable.Spatial expansion in Jinan mainly extends towards the east and west wings,and the boundary conforms to the spatial strategy guiding Jinan’s development and is consistent with the overall layout in related plans.Considering both ecological protection and the internal forces driving urban expansion,the method of urban growth boundary delimitation used in this study can provide a reference and practical help for studies and management of urban development in the new era.展开更多
Under the initiative of“encouraging 300 million people to participate in ice and snow sports”and the guidance of the‘Evidence-based’policy-making process,this study takes the Hierarchical Model of Leisure Constrai...Under the initiative of“encouraging 300 million people to participate in ice and snow sports”and the guidance of the‘Evidence-based’policy-making process,this study takes the Hierarchical Model of Leisure Constraints as the theoretical framework to empirically explore the constraints influencing the participation of residents in Southern China in ice and snow sports.After factor analysis,the constraint dimension of residents’participation was obtained,and the constraints of participants and non-participants were evaluated and compared by Propensity Score Matching(PSM).The results indicate that Chengdu residents have potential interest in and demand for winter sports,and the constraint dimensions are:facilities and services,companions,time,and personal feelings.The predisposition scores of the experimental group and the control group revealed that the constraints on interest,relevant knowledge and skills,and personal feelings of the participating group were significantly lower than those of the non-participating group,while the other constraints were not significant.We suggest that efforts should be made to increase the effective supply according to local conditions in order to reduce structural constraints,and the social attributes should be integrated into ice and snow sports to resolve the inter-personal constraints.展开更多
Land plants in natural soil form intimate relationships with the diverse root bacterial microbiota. A growing body of evidence shows that these microbes are important for plant growth and health. Root microbiota compo...Land plants in natural soil form intimate relationships with the diverse root bacterial microbiota. A growing body of evidence shows that these microbes are important for plant growth and health. Root microbiota composition has been widely studied in several model plants and crops; however, little is known about how root microbiota vary throughout the plant's life cycle under field conditions. We performed longitudinal dense sampling in field trials to track the time-series shift of the root microbiota from two representative rice cultivars in two separate locations in China. We found that the rice root microbiota varied dramatically during the vegetative stages and stabilized from the beginning of the reproductive stage, after which the root microbiota underwent relatively minor changes until rice ripening. Notably, both rice genotype and geographical location influenced the patterns of root microbiota shift that occurred during plant growth. The relative abundance of Deltaproteobacteria in roots significantly increased overtime throughout the entire life cycle of rice, while that of Betaproteobacteria, Firmicutes, and Gammaproteobacteria decreased. By a machine learning approach, we identified biomarker taxa and established a model to correlate root microbiota with rice resident time in the field(e.g., Nitrospira accumulated from 5 weeks/tillering in field-grown rice). Our work provides insights into the process of rice root microbiota establishment.展开更多
This article analyzes the impact of urbanization on village democracy in China. The "economic absorption and social exclusion" of semiurbanization path has attracted rural residents to cities. These people participa...This article analyzes the impact of urbanization on village democracy in China. The "economic absorption and social exclusion" of semiurbanization path has attracted rural residents to cities. These people participate in the urban economy just as a factor of production (labor) without enjoying the rights that urban citizens(xfiUagers) have. This urbanization path and population mobility has had a profound influence on rural democracy in China. On the one hand, large numbers of young people have left; the traditional villages in central and western China, which are characterized by population output( many even move with their entire families), causing the villages to lose their political elite while the interaction chain between villagers has been shortened and social trust in the villages has been weakened, thereby giving rise to a low quality of rural democracy. On the other hand, large numbers of migrant workers have flocked into the urbanized villages in eastern China, which are characterized by population input, and these people far outnumber local residents. Migrant workers are excluded from rural democracy and the governance structure. This local citizenship based on the household registration system restricts the inclusiveness of village democracy.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.40671058,41071102)National'TwelfthFive-Year'Plan for Science and Technology Support(No.2012BAJ 05B04)
文摘China's transition from a planned economy to a market economy has resulted in many changes in its urban structure and society and provided an opportunity for a quasi-longitudinal case study on the relationship between the built environment and activity-travel behavior.This paper draws upon data from an activity diary survey conducted in Beijing in 2007.The survey sample comprised 652 residents living in Danwei(work unit),commodity housing,and affordable housing neighborhoods.On the basis of the three-dimensional geo-visualization analysis of the space-time path and statistical multivariate regression models of daily travel and leisure time,it was found that both residential spatial factors and socio-demographics influence residents' daily behaviors.The findings show that Danwei residents have less daily travel time than those who live in commodity housing,but people living in affordable housing endure the longest travel time.Daily leisure time is associated more with individual attributes.We argue that although China's transition is currently gradual,the Danwei system may continue to play significant roles in daily life,and it might provide a valuable model for neighborhood spatial planning.
文摘Under the planned economy,China’s distribution relations were relations among the state,state-run enterprises,employees and the collective economy;relations between heavy industry and light industry;and relations between cities and the countryside.After China’s transition to a market-oriented economy,the distribution relations among the state,state-run enterprises and employees evolved into distribution relations between the government,enterprises and households;the distribution relations between heavy industry and light industry evolved into distribution relations between the state sector and the private sector;and the distribution relations between cities and the countryside evolved into distribution relations between original urban dwellers and migrant populations.Wage system reform was carried out throughout the transition of these three types of distribution relations.Income distribution contradictions in China,which are a problem left over from history and intrinsic to the market-based economy,eased over the years.Some people and regions achieved prosperity,and urban-rural and interregional income gaps narrowed.However,widening household income gaps pose barriers to China’s economic sustainability and vision of building a moderately prosperous society in all respects.Mechanisms to promote common prosperity are incomplete and inadequate.The disequilibrium of functional distribution is an important cause of these income inequalities.The overall wage level of ordinary workers is low.In the future,China'should give full play to the decisive role of the market in primary distribution to ensure proper return to all types of factors,and enhance redistribution to achieve common prosperity for all its people.
基金support for this study by the International Project of "Rice-fish GIAHS Dynamic Conservation and Adaptive Manage-ment"the Institute of Geographical Sciences and Natural Resources Research of the Chinese Academy of Sciences (the Project of Dynamic Conservation and Adaptive Management of Rice-fish System)the Qingtian Government (the Master Plan of GIAHS Conservation)
文摘Globally Important Agricultural Heritage Systems (GIAHS) is a wide program to promote the conservation and adap-tive management of such systems and their associated landscapes, biodiversity, knowledge systems and cultures. Rice-Fish Systems (RFS) in Longxian village of China, as a traditional agricultural system, was selected as one of the five pilot sites of GIAHS in 2005. Researchers have paid more attention to the dynamic conser-vation and adaptive management of RFS because it is under severe threats from global development challenges. Tourism is suggested to be brought into the RFS conservation program as an alternative industry. This paper presents a comparative study of residents in three types of farm household in Longxian, seeking attitudes to the RFS conservation and tourism development and ways in which such information may guide future strategies. Results show resi-dents, belonging to the household type in which most family mem-bers are abroad, have the most positive attitudes to RFS conserva-tion and tourism development; while residents, as other household type in which less than 50% of family members are abroad, are the least sensitive group in these three household types, due to the motivation of moving abroad weakening their enthusiasm to participate in the local activities. Implications are discussed in the context of how resident attitudes will affect the future manage-ment of GIAHS conservation and tourism development, and then measures are put forward to foster tourism cooperation and multi-stakeholders process establishment.
基金Under the auspices of Key Research Program of Chinese Academic of Science(No.KZZD-EW-06-03,KSZD-EW-Z-021-03)Advantage Discipline Project of Hainan Normal University(No.305010048)+2 种基金Key Discipline Project of Hainan(No.3050107048)National Natural Science Foundation of China(No.41201160,41329001)Natural Science Foundation of Hainan Province(No.414189)
文摘Quality of life(QOL) is a hotspot issue that has attracted increasing attention from the Chinese Government and scholars, it is also a vital issue that should be addressed during the cause of ′establishing overall well-off society′. Northeast China is one of the most import old industrial bases in China, however, the industrial structure of heavy chemical industry and the development mode of ′production first, living last′ have leaded to series of social problems, which have also become a serious bottleneck to social stability and economic sustainable development. Through applying the methods of BP neural network, exploratory spatial data analysis(ESDA) and spatial regression model, this paper examines the space-time dynamics of QOL of the residents in Northeast China. We first investigate the indexes of QOL of the residents and then use ESDA methods to visualize its space-time relationship. We have found a spatial agglomeration of QOL of the residents in middle-southern Liaoning Province, central Jilin Province and Harbin-Qiqihar-Daqing area of Heilongjiang Province. Two third of the counties are low-low spatial correlation, and the correlative type of about 60% of the prefecture level areas keeps stable, indicating QOL of the residents in Northeast China shows a certain character of path dependence or spatial locked. We have also found that economic strength and development levels of service industry have positive and obvious effect on QOL of the residents, while the effect of such indexes as the social service level and the proportion of the tertiary industries are less.
文摘The paper presents the possibilities of implementing micro-simulation traffic tools in order to develop the evacuation plans. Well elaborated evacuation plans are the basis for alleviating the consequences resulting from emergencies. The simulation tools allow the design and verification of various evacuation planning scenarios with minimisation of costs and time. The paper provides detailed presentation of the basic characteristics of microscopic simulation of traffic flows, as well as examples of their implementation worldwide. The characteristics of the software tools are described through an overview of the basic settings ofPTV VISSIM (Planung Transport Verkehrin Stadten--Simulations model) program as one of the most significant representatives of these tools. The necessity of implementing the traffic tools in evacuation results from the crucial role of traffic in reducing the consequences of emergencies. These tools allow also a detailed analysis of the output data in order to select a suitable solution. The concluding part of the paper presents an example of evacuation of the population through the Jankomir node as part of the European project "preparedness for evacuation in case of a nuclear accident". The evacuation was performed through three scenarios in circumstances of higher or lower transport demand.
基金supported by Scientific and Technological Major Project in National Eleventh Five-Year Plan (Grant No. 2006BAJ05A04)
文摘During the rapid urbanization period, the contradiction between demand for the construction land and the preservation of cultivated land for food security is getting more and more serious in China. With the urbanization the rural settlement land is increasing instead of decreasing; This paper aims at.finding the driving forces for rural settlement land expanston. Based on land use change survey data (1996-2006) by the Ministry of Land and Resources P. R. C., this paper find, that per capita area for rural settlement land is more than per capita area for city; township and industrial land in each province except Tibet. Besides, rural settlement land area and per capita rural settlement land area are increasing while the rural poputation is decreasing in most provinces. The main problems of rural settlement land use are low efficiency, high vacancy rate, chaotic layout and illegal occupancy. Then the driving forces [br rural settlement land expansion, including economic development, family income, family scale, psychological factors, urbanization, transportation, lack of planning, limited circulation of dwelling-house land and imperfect sociat security, ate explored based on above analysis, Finalty, policy recommendations, in view of different influencing factors, are put forward to control the disorder expansion of rural setttement land.
文摘This paper studies factors influencing rural-urban labor migration in China,particularly the implementation of rural cooperative medical insurance(RCMI) in the year 2003.With the support of data analysis from the year 2000,2004 and 2006,clear linear correlations are found between gender,income,health condition and rural-urban labor flow,whereas the impact of education and employment status are more complicated.More importantly,results from regression show that the establishment of RCMI in countryside of China not only inhibits rural residents from seeking employment outside the village,but also pulls back rural people who have already worked in cities.When regional dimension is concerned,the pure composite effect of RCMI on rural labor flow is less significant in coastal areas with better economic performance and medical service.
文摘The importance of social sports in urban development show that it makes the quality of urban residents greatly improved and becomes a strong surge of power to promote the development of economy; it makes the cultural connotations of the city more abundant and becomes the propeller of urban cultural development. And the specific roles show that it forms the group of physical and mental health in the city; it makes sports become an important part of people' s lives; it cultivates and enhances the citizens' sense of honor; it improves the urban management and enhances the image of the city.
基金supported by the National Natural Science Foundation of China(21175025)
文摘Concentrations of PCDD/Fs, dioxin-like PCBs as well as six indicator PCBs were determined in animal origin foods collected from Hong Kong retail market during 2008-2010. The dietary intake of an average Hong Kong adult resident was estimated to be 0.806-0.833 pg WHO-TEQ kg^-1 b.w. d^-1 of dioxin-like compounds, lower than the tolerable daily intake introduced by WHO. The 95th percentile consumer were exposed by dietary at the level of 2.72 to 2.81 pg WHO-TEQ kg^-1 b.w. d^-1 or 81.6-84.3 pg WHO-TEQ kg^-1 b.w. month^-1 , higher than 70 pg WHO-TEQ kg t b.w. month^-1. DL-PCBs contributed 49.2% of total TEQ intake. The daily intake of indicator PCB was 2.83 ng kg^-1 b.w. d^-1. Approximately 2/3 of dietary intake of dioxin-like compounds came from sea food products. Ten brands of infant formula products were tested and the potential dietary intake of formula-fed infants of Hong Kong was estimated to be 1.46-1.58 pg WHO-TEQ kg^-1 b.w. d^-1 during 1st month and decreases afterwards.
基金National Natural Science Foundation of China(41430861)
文摘Delimitation of an urban growth boundary(UGB)can effectively curb disorderly urban expansion,optimize urban development space and protect the ecological environment.Eco-environmental sensitivity was evaluated and areas prohibiting construction expansion were extracted by establishing an index system.Point of interest(POI)and microblog data were utilized to analyze the expansion of residential activity space.Urban space expansion potential was calculated using a comprehensive evaluation model,and an urban growth boundary for Jinan in 2020 was delimited combining the predicted urban expansion scale.The results showed that:(1)An evaluation of eco-environmental sensitivity can effectively protect ecological land and provide an ecological basis for urban expansion.Regions with high eco-environmental sensitivities in Jinan are located along the banks of the Yellow River and Xiaoqing River and in southeast mountainous areas,but eco-environmental sensitivities in the central,north and southeast areas are relatively low;(2)The model to evaluate urban residential activity expansion can quantify the spatial distribution of urban residents’activities.Regions with high potential for residential activity space expansion in Jinan are mainly concentrated in the middle of Jinan and most are part of existing built-up areas and surrounding areas;(3)The method that delimits urban growth boundaries based on the coordination of ecology and residential activity space is reasonable.Spatial expansion in Jinan mainly extends towards the east and west wings,and the boundary conforms to the spatial strategy guiding Jinan’s development and is consistent with the overall layout in related plans.Considering both ecological protection and the internal forces driving urban expansion,the method of urban growth boundary delimitation used in this study can provide a reference and practical help for studies and management of urban development in the new era.
基金The National Social Science Foundation of China(17CTY014).
文摘Under the initiative of“encouraging 300 million people to participate in ice and snow sports”and the guidance of the‘Evidence-based’policy-making process,this study takes the Hierarchical Model of Leisure Constraints as the theoretical framework to empirically explore the constraints influencing the participation of residents in Southern China in ice and snow sports.After factor analysis,the constraint dimension of residents’participation was obtained,and the constraints of participants and non-participants were evaluated and compared by Propensity Score Matching(PSM).The results indicate that Chengdu residents have potential interest in and demand for winter sports,and the constraint dimensions are:facilities and services,companions,time,and personal feelings.The predisposition scores of the experimental group and the control group revealed that the constraints on interest,relevant knowledge and skills,and personal feelings of the participating group were significantly lower than those of the non-participating group,while the other constraints were not significant.We suggest that efforts should be made to increase the effective supply according to local conditions in order to reduce structural constraints,and the social attributes should be integrated into ice and snow sports to resolve the inter-personal constraints.
基金supported by the“Strategic Priority Research Program”of the Chinese Academy of Sciences(XDB11020700)CPSF-CAS Joint Foundation for Excellent Postdoctoral Fellows(2016LH00012)+1 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(QYZDB-SSW-SMC021)the National Natural Science Foundation of China(31772400)
文摘Land plants in natural soil form intimate relationships with the diverse root bacterial microbiota. A growing body of evidence shows that these microbes are important for plant growth and health. Root microbiota composition has been widely studied in several model plants and crops; however, little is known about how root microbiota vary throughout the plant's life cycle under field conditions. We performed longitudinal dense sampling in field trials to track the time-series shift of the root microbiota from two representative rice cultivars in two separate locations in China. We found that the rice root microbiota varied dramatically during the vegetative stages and stabilized from the beginning of the reproductive stage, after which the root microbiota underwent relatively minor changes until rice ripening. Notably, both rice genotype and geographical location influenced the patterns of root microbiota shift that occurred during plant growth. The relative abundance of Deltaproteobacteria in roots significantly increased overtime throughout the entire life cycle of rice, while that of Betaproteobacteria, Firmicutes, and Gammaproteobacteria decreased. By a machine learning approach, we identified biomarker taxa and established a model to correlate root microbiota with rice resident time in the field(e.g., Nitrospira accumulated from 5 weeks/tillering in field-grown rice). Our work provides insights into the process of rice root microbiota establishment.
文摘This article analyzes the impact of urbanization on village democracy in China. The "economic absorption and social exclusion" of semiurbanization path has attracted rural residents to cities. These people participate in the urban economy just as a factor of production (labor) without enjoying the rights that urban citizens(xfiUagers) have. This urbanization path and population mobility has had a profound influence on rural democracy in China. On the one hand, large numbers of young people have left; the traditional villages in central and western China, which are characterized by population output( many even move with their entire families), causing the villages to lose their political elite while the interaction chain between villagers has been shortened and social trust in the villages has been weakened, thereby giving rise to a low quality of rural democracy. On the other hand, large numbers of migrant workers have flocked into the urbanized villages in eastern China, which are characterized by population input, and these people far outnumber local residents. Migrant workers are excluded from rural democracy and the governance structure. This local citizenship based on the household registration system restricts the inclusiveness of village democracy.